Facebook & Myspace Essay Example | Topics and Well Written Essays - 500 words

Facebook & Myspace - Essay Example Both the communities have a somewhat different target audience. As FaceBook was originally offered only to the Harvard Business Students and later they became public therefore an average person on the website is a either a college student or a recently passed college graduate. However MySpace has a much broader audience with a diverse array of users. As far as comparing the essential features of both the websites, MySpace has got a hand over FaceBook in terms of personalization and customization of user profiles. MySpace is potentially flexible as it allows its user to express them in a broader way and users can incorporate a diverse range of colours, personal photos and flash applications to their pages. We know that the most of the revenue generated by these types of web communities is through advertisement therefore it has a profound implication. In the future the businesses would be targeting to individual needs and preferences therefore MySpace would be considered as a better source of partnering and placing your ads. One of the research firm predicted that MySpace will sell $525 million worth of advertising, whereas FaceBook will be able to sell only $125 million (Kirkpatrick, 2007). This financial impact shows that the personalization of content has provided a greater leverage to MySpace. When it comes to customer privacy, FaceBook does ensure maximum security and protects the privacy of the users better than the MySpace. The reason is that the FaceBook was first launched for private community (Harvard Students) therefore it is relatively secure. Whereas MySpace was initially targeted to a much larger group therefore it is open to many and different kind of users. One of the critical issues faced by MySpace is of spamming as the users are inundated with spam and pornographic comments. Every other day you would find that you are being requested by tons of anonymous users. It is socially acceptable to request a random person via

Ethics in the Classroom Essay Example for Free

Ethics in the Classroom Essay Assessments have been in existences for many years; however schools have implemented various technology programs due to changes which have occurred in the educational system. Technology has become an innovative way to document, record, and to expand student’s learning. Teachers have access to software and hardware which is used to teach students required information as well as prepare them for the world outside the confines of a classroom. This plan will explain how software is used to support assessment in the classroom, such as formative and summative assessment and how technology may be used to support these two assessments. The plan will take a glimpse into the pros and cons of using technology and the teachers’ use of technology in the classroom. Although this plan is not intended to be a required plan for any teacher, it offers a suggestive approach to the use of technology based assessment in the school system. Teachers use assessments throughout their teaching careers to help evaluate a student’s learning process. Assessments also help to gather information for others to view such as; information pertaining to the schools in their school district, the students serviced (demographics) and test results. In a recent article online, Formative and Summative Assessments in the Classroom, Ehringhaus Garrison state â€Å"Assessment is a huge topic that encompasses everything from statewide accountability tests to district benchmarks or interim test to everyday classroom tests† (2012, p2). The two types of assessments teachers used are formative and summative, which â€Å"being creative with formative and summative assessment can seem a daunting task, but technology can assist with this and give students accessible ways to widen both ideas about assessment and kinds of assessments that students took†(Senate Office on Assessment, 2012,p1). Formative assessment is used to gather information that can be used to improve the teaching and learning of students. The main difference amongst formative and summative assessment would be how the information would be used. â€Å"When it comes to improving instruction and learning, it’s not the quantity of the data that counts, but how information is used† (Harris, Lewis, Muoneke Times, 2010, p. 1). Although formative assessments can be done daily, weekly, or when needed, the information may be used to create a lesson plan which meets the needs of the students in his/her classroom. The summative assessments are done at the end of a course or semester; however they may contain other information such as age, race or gender and may cover general information taught over the course of a school year. The use of assessments in technology can also be challenging for some teachers and students. Therefore, educators should compare the pros and cons of using technology in the classroom and assessment of students. Technology has increased in the classroom, and with the change in technology there is a change in the way assessments are done. Usage of technology to help assess students can benefit in many ways, it can enhance the learning process of students by â€Å"help(ing) students visualize problems they may encounter and reach students with different learning styles, including visual, auditory, and experiential learners† (Teaching with Technology, 2012, pg. 3). On the other spectrum of technology it can be costly to school district depending if the schools request wired or wireless hardware. Regardless of the use of technology in the classroom or for assessments, teachers must assess their students to help understand and implement the needs of the students. Software to Support Assessment Assessments have been in existences for many years; however schools have implemented various technology programs due to changes which have occurred in the educational system. Technology has become an innovative way to document, record, and to expand student’s learning. Teachers have access to software and hardware which is used to teach students required information as well as prepare them for the world outside the confines of a classroom. This plan will explain how software is used to support assessment in the classroom, such as formative and summative assessment and how technology may be used to support these two assessments. The plan will take a glimpse into the pros and cons of using technology and the teachers’ use of technology in the classroom. Although this plan is not intended to be a required plan for any teacher, it offers a suggestive approach to the use of technology based assessment in the school system. Teachers use assessments throughout their eaching careers to help evaluate a student’s learning process. Assessments also help to gather information for others to view such as; information pertaining to the schools in their school district, the students serviced (demographics) and test results. In a recent article online, Formative and Summative Assessments in the Classroom, Ehringhaus Garrison state â€Å"Assessment is a huge topic that encompasses everything from statewide accountability tests to district benchmarks or interim test to everyday classroom tests† (2012, p2). The two types of assessments teachers used are formative and summative, which â€Å"being creative with formative and summative assessment can seem a daunting task, but technology can assist with this and give students accessible ways to widen both ideas about assessment and kinds of assessments that students took†(Senate Office on Assessment, 2012,p1). Formative assessment is used to gather information that can be used to improve the teaching and learning of students. The main difference amongst formative and summative assessment would be how the information would be used. â€Å"When it comes to improving instruction and learning, it’s not the quantity of the data that counts, but how information is used† (Harris, Lewis, Muoneke Times, 2010, p. 1). Although formative assessments can be done daily, weekly, or when needed, the information may be used to create a lesson plan which meets the needs of the students in his/her classroom. The summative assessments are done at the end of a course or semester; however they may contain other information such as age, race or gender and may cover general information taught over the course of a school year. The use of assessments in technology can also be challenging for some teachers and students. Therefore, educators should compare the pros and cons of using technology in the classroom and assessment of students. Technology has increased in the classroom, and with the change in technology there is a change in the way assessments are done. Usage of technology to help assess students can benefit in many ways, it can enhance the learning process of students by â€Å"help(ing) students visualize problems they may encounter and reach students with different learning styles, including visual, auditory, and experiential learners† (Teaching with Technology, 2012, pg. 3). On the other spectrum of technology it can be costly to school district depending if the schools request wired or wireless hardware. Regardless of the use of technology in the classroom or for assessments, teachers must assess their students to help understand and implement the needs of the students. To help facilitate the ongoing assessment of student’s learning; teachers may require students to do assignments outside of school. This could include visiting educational sites to help support the content taught in class. Teachers may also allow students to do presentations, such as writing papers, finding information on the web and also interactive sites. Also to help parents stay informed about their child’s learning process; parent sites are also available to view their student’s grades and testing scores. Assessments can help to oversee the progression of students, and incorporating the use of technology to help with assessment can help to relieve the stress of keeping up with many forms and paperwork, but over usage can become mundane for students. However, â€Å"as good as technology-based assessment and data systems might be, educators need support in learning how to use them. (U. S. Department of Education, 2012, p1). Information on proper use of technology should be administered to teachers before they can teach the information to their students. The introduction of hardware such as Promethean boards allows the professional development department to develop courses which have become a requirement of the teachers’ certification process. This ensures teachers have received instruction on how to implement te chnology in the classroom and the use of software to support assessment. Teachers should not rely solely on the use of technology as a form of assessment due to inaccuracy of data information. Sometimes human errors may cause problems with a students? grades or information. Over usage of technology can also obscure the information with students who may learn in a different manner. Technology can help assess students using formative and summative assessments, which can increase the learning process of students by continuing ongoing assessments to help facilitate the learning process.

Lamb to the Slaughter and The Speckled Band :: English Literature

Both Lamb to the Slaughter and The Speckled Band share some characteristics of murder mysteries. What are the similarities and differences between the two stories? I this essay I am going to compare two short stories. 'The Speckled Band' by Sir Arthur Conan-Doyle and 'The Lamb to the Slaughter' by Roald Dahl. There are both many similarities and difference between these two stories. Though some similarities/differences are obvious and easy to spot, there are also some less obvious similarities/differences. The first difference we can see is the setting. 'In Lamb to the Slaughter', the main setting is in a quiet, warm house. 'The room was warm and clean, the curtains drawn, the two table lamps alight - hers and the one by the empty chair opposite.' This description tells us about how the house is appealing to be in. Also, by saying the 'empty chair opposite' you can gather that there is another character in the story, to which she is waiting for. The time period is a post 20th Century America (1954, about 10 years after the Second World War.) However, the main setting in 'The Speckled Band' is the complete opposite. 'The building was of grey, lichen-blotched stone, with a high central portion, and two curving wings, like the claws of a crab, thrown out on each side.' This gives a foreboding atmosphere, which could be used to en-still fear into readers. Another difference is that it is set in 19th Century England. Though both very different, both settings hold a murder to them. Other differences are in the way the characters are depicted. In 'Lamb to the Slaughter' the main character, Mary Maloney, is described as a quiet peaceful person. 'Curiously tranquil eyes with their new placid look, seemed larger, darker than before.' The writer also indicates that she is pregnant, 'for this was her sixth month with child.' With this description, you would not think of Mary to be a 'typical killer'. What people consider a typical killer is someone who is cold, precise and knows what they're doing, usually a man. However we are misled, 'brought it down as hard as she could on the back of his head. She might just have hit him with a steel club.' As you can see, this would not have been expected from a quiet tranquil person. There are no more descriptions of other people. This is strange as you would think that there would be more people in the story. Even though more people come into the story, they are not significant enough to get a description. They are just said to be a 'police detective'.

Permanent Change In An Individuals Knowledge Or Behaviour

Learning can be ocular, kinesthetic, musical, interpersonal, intrapersonal, lingual, logical, realistic, religious and moral, and, consequentially, scholars have really differing degrees of intelligence in these different sorts of larning. It is per se of import for instructors to hold a on the job cognition of how different pupils learn because of this fact that non all pupils learn in the same manner. An educators occupation is to ease acquisition for a pupil, and hence must be adaptable to these assorted acquisition manners in order to adequately supply for them, and this can non be done without an apprehension of different larning theories and manners. A pupil who is kinesthetic or visually intelligent is non traveling to profit from certain manners of learning every bit much as a pupil who is a logical scholar, presuming the pedagogue is merely learning in a logical manner. Therefore it is necessary for pedagogues to understand the differing sorts of larning so that they can pro vide for multiple intelligences within their lessons, both by admiting their being and leting pupils the chance to larn in different ways every bit good as developing pupils abilities to interact with intelligences that they might otherwise be non as accustomed to. Equally good as different intelligences there are different worldviews on how learning occurs, whether it is inactive or active, whether it is societal or personal, and these theories straight affect the teaching method embraced by the instructor keeping them. Therefore the acquisition theories will needfully order the types of intelligences most supported by the acquisition that is taking topographic point, and it is up to the pedagogue to understand these learning theories so that they may use them in a manner to outdo explore all of the multiple intelligences and give their pupils the best opportunity of making a higher order apprehension of any capable affair. Behaviourism is a theory that operates upon an ‘action-reaction ‘ or ‘stimulus-response ‘ construct of larning. At its kernel this worldview places the scholar in the place of being a ‘blank slate ‘ , an empty vas or ‘tabula rasa ‘ , which is so filled with the coveted cognition or acquisition. Behaviourism assumes that the scholar is inactive and that they respond to any and all environmental stimulations that they are exposed to. The environment acts on the scholar, non the scholar on the environment. Behaviorism can be broken down into two possible signifiers of conditioning: classical conditioning and operant conditioning, the late of which was founded by B. F. Skinner and is one of the most outstanding larning theory places. Skinner ‘s operant conditioning position is non-dualistic, it denies that the head is a separate thing to the organic structure, alternatively situating ideas to be private behaviors, analysable in the same manner that public behaviors are. Essentially learners learn to ‘operate ‘ on the environment. Functionally, operant conditioning plants on a footing of support and penalty. Reinforcement is a procedure by which a targeted behavior is caused to happen with greater frequence and penalty a lesser frequence. Both these effects have positive and negative fluctuations, by positive and negative we refer to their linear or subtractive qualities, non their moral deductions. Positive support is when a rewarding stimulation is to happen following a desirable behavior, therefore increasing its frequence. Negative support occurs when an unwanted stimulation is removed after a desirable behavior, besides increasing its frequence. Positive penalty is the happening of a penalty or negative stimulation following an unwanted behavior, diminishing its likelihood, while negative penalty is the remotion of a positive or honoring stimulation following a unsought behavior, besides diminishing the opportunity of reoccurrence. In contrast to behaviorism, constructivism positions the scholar as an active participant in the acquisition procedure. The scholar is an â€Å" information builder †[ 3 ], one of the basic premises behind constructivism is that â€Å" people are active scholars and must build cognition for themselves. †[ 4 ]This base premise is that the scholar is a â€Å" alone person with alone demands and backgrounds. †[ 5 ] Learning is a constructive, contextualized and active procedure by which the scholar is engaged in actively making a subjective reading of an otherwise nonsubjective world. One of the cardinal differences between constructivism and behaviorism is that the scholar is seen as conveying past experience and cognition to the acquisition, and that it is this past experience that is the specifying factor in the defining and constructing of new cognition. This construct at work postulates that people generate their appreciation on cognition through an interaction between their thoughts and experiences. Furthermore the scholar acts upon the environment, interacting with it to make significance, instead so being acted upon. Constructivism, nevertheless, is non a incorporate theory. Under the streamer of constructivism subsists three chief positions dubbed the exogenic position, the endogenous position and the dialectical position. An exogenic constructivism â€Å" position posits a strong influence of the external universe on cognition building, such as by experiences, instruction, and exposure to theoretical accounts. Knowledge is accurate to the extent it reflects that world. †[ 6 ]On the other manus, endogenous constructivism provinces that cognition is derived from earlier mental constructions and focal points on a coordination of â€Å" cognitive actions †[ 7 ], while dialectical constructivism is a blend of the two, situating that cognition is non wholly construed from the external universe, nor is it entirely of the head but instead is the consequence of interactions between the scholar and the environment. – Schunk, Dale H. ( 2008 ) Constructivist Theory ( Chapter 6 ) . In Learning Theories: An Educational Perspective. 5th Edition. ( pp.234-277 ) . Upper Saddle River, New Jersey: Pearson, Merrill Prentice Hall. ISBN 9780132435659 pg 239 A behaviorist schoolroom places the scholar in a inactive function, as earlier mentioned, they are ‘tabula rasa ‘[ 8 ]. As a consequence the pedagogue is positioned in an active function, basically ‘acting ‘ on the scholar to instil cognition. This can take to a schoolroom where the scholar is non needfully encouraged to prosecute with the cognition presented to them, but instead to basically digest it, taking the cognition in to regurgitate ‘as is ‘ when needed. There is nil incorrect with this type of acquisition, so for certain topics and certain countries of topics it is arguably the most efficient signifier of acquisition. However a failing nowadays within the behaviorist theory is that it does non let the scholar to come on much further so the ‘applying ‘ phase in the new blooms taxonomy. It may be wrong to state that it does non ‘allow ‘ , but it surely does non promote the scholar to come on farther into the analysin g, measuring and making phases of the theoretical account without proper motion into determining the scholars behaviour. Even though they may acquire their ain their ain, the attack does non supply scaffolding to back up the scholar to these more advanced interactions with the cognition. This is because the scholar is non forced to prosecute with the cognition in an active manner, they do non hold to do it their ain, alternatively expected to be able to retrace what the instructor has presented to them, demoing an ability to retrieve and reproduce, but non needfully to grok on a meaningful degree. On the other manus a constructivist attack efforts to guarantee that the scholar interacts on a degree that allows them to prosecute in making from the footing of the cognition conveyed, hence promoting higher order thought. However In a behaviorist schoolroom the instructor will be actively seeking to place behavior to be changed, and, one time identified, they will be after specific intercessions to change that behavior in a coveted manner utilizing ancestors and effects. The instructor invariably accumulates informations on the consequences of these intercessions and modifies their attack to more efficaciously ‘shape ‘ the pupils behaviour. Praise, although contingent upon the behavior of the pupil, will strategically and often be given out to reenforce coveted behaviors. Each lesson will hold clear and precises ends in footings of cognition, attitudes and accomplishments to be transferred to the pupils, and cues and prompts will be utilized in order to put up behavioral forms and determine the pupils into the coveted acquisition form. This would so be scheduled with uninterrupted regular support to get down with, followed by more intermittent and sporadic support to ease the pupil into ego regula ted acquisition. This defining is necessary because a rigorous behaviorist attack is merely utile for a short period of clip, determining is required to foster the pupils larning. In an English schoolroom it would be expected that the instructor would be actively reenforcing the battle of pupils in category treatment with prima and directed oppugning accompanied with congratulations for engagement. The teacher*/*** As a instructor it is of import to gain that behaviorism does work, it is a important portion of any instruction and has a really effectual and functional intent but that it is non all of the image. As with the demand to be various in learning to cover the multiple intelligences, so excessively do we hold to be various in the theories we use in our pattern. While behaviorism is a really of import tool we can utilize, and basically covers a big part of the behaviour direction and positive forms we can put in the category, we still need constructivism in order to ease * Piaget posited four phases that all human existences go through in the procedure of ripening. The sensorimotor phase is that phase â€Å" from birth to age 2. Children experience the universe through motion and senses ( utilize five senses to research the universe ) † -Santrock, John W.. Children. 9. New York, NY: McGraw-Hill, 1998. The preoperational phase consists of kids from ages two to seven and consists of egoism and begins to see the universe symbolically, so the kids begin to believe logically and travel into the concrete operational phase between ages seven and twelve and eventually from age 12 onwards reach the formal operation phase and develop abstract logical thinking. â€Å" the fact that many of the voluntary responses of animate beings and worlds are strengthened when they are reinforced ( followed by a desirable effect ) and weakened when they are either neglected or punished. † â€Å" †¦ organisms learn new behaviors and when to exhibit them and E »unlearnE? bing behaviors. † â€Å" †¦ all behaviors are accompanied by certain effects, and these effects strongly influence whether these behaviors are repeated and at what degree of strength. † â€Å" Positive interactions between instructor and pupils can bring forth successful acquisition results in the presence of complex kineticss of individuals, conditions and results. † Snowman et Al. ( 2009 ) . Chapter 7. â€Å" Behavioural Learning Theory: Operant Conditioning † . In Psychology Applied to Teaching. 1st Australian Edition. Milton, QLD: John Wiley & A ; Sons Australia Ltd. Bibliography

49 Simple Things You Can Do to Save the Earth Essay

Some of them, with their complicated timers and instant start-up features, constantly consume small amounts of electricity. (â€Å"Even the TV?† my wife asks. â€Å"Good thinking,† I tell her.) 3. SEPARATE YOUR GARBAGE. At our house we have separate garbage cans for glass, paper, plastic, aluminum, wood, organic matter, natural fabrics, synthetic fabrics, and rubber. (We split the work—my wife does the separating, I drop everything off at the recycling center.) 4. USE LESS WATER. We have two bricks in our toilet tank. But there’s a much simpler way to save water: Don’t flush every time! (â€Å"Don’t take the sports section in there with you!† is my wife’s tip. A sense of humor isso important.) 5. DON’T MOW THE LAWN. Let it grow. Naturally. Like a meadow. (â€Å"Like a dump!† jokes my wife.) See more:  Perseverance essay 6. DON’T SHAVE AS OFTEN. I shave once a week. (â€Å"If it’s good enough for Don Johnson,† I quip. â€Å"That was passà © years ago,† my wife informs me.) 7. DRIVE SLOWER. I try to maintain a nice, steady 40 miles per hour, the legal minimum on most highways. Also, I roll up the windows. It reduces wind resistance — and noise. (â€Å"You can’t hear those horns?† my wife asks, incredulous.) 8. SHOP WITH A RE-USABLE SHOPPING BAG. And, if you can, walk to the store. (â€Å"It’ll do wonders for your figure,† I mention casually to the missus.) 9. BOYCOTT! Boycott polluters, or anyone who sells any product that can cause pollution, or any product that might contain an ingredient that can cause pollution. (â€Å"What does that leave?† my wife asks. â€Å"Just the good stuff,† I reply.) 1 0. DO YOUR LAUNDRY BY HAND. It may be drudgery of the lowest order to have to hand-launder your clothes and hang them on a clothesline, but it saves water and energy. (â€Å"Whistle while you work,† I kid my wife. â€Å"Hitler is a jerk,† she continues. I’d forgotten that verse!) 11. TURN DOWN THE HEAT. Especially the water heater. (â€Å"They take cold showers in Sweden,† I like to hint. â€Å"Go to Sweden!†Ã¢â‚¬â€my wife.) 12. TAKE FEWER SHOWERS. But don’t share them, even if it’s been touted, albeit humorously, in other â€Å"x-number-of-simple-things-you-can-do-to-save-the-earth† books. Why? It uses more water. Figure it out for yourself. Better would be to take a bath in â€Å"recycled† bath water. Best: An occasional sponge bath. (â€Å"No, I’m not kidding,† I tell the wife.) 13. REPLACE METAL DOORKNOBS. During the winter, when it’s very dry, touch a metal doorknob and you get a little shock from the static electricity. That’s wasted electricity, I figure. We’ve replaced all our metal doorknobs with ones made of non-conducting rubber, wood or glass. (â€Å"You’ve got a screw loose,† my wife points out. And she’s right!) 14. GO SOLAR. For a small investment of about ten thousand dollars you can convert your house to solar energy. It’ll pay for itself in twenty years, I estimate. (â€Å"What next?† my wife wonders, as we all do.) 15. MOUNT A WINDMILL ON YOUR ROOF. It’s cheap—about eight hundred dollars—and easy to install. (â€Å"A little more to the right,† I yell up to her.) 16. MAKE YOUR OWN HONEY. In addition to producing delicious honey, our beehive is a real conversation starter. (â€Å"We have to talk,† my wife says. See?) 17. WORK AT HOME. Recently, I quit my job of twenty years to become a full-time writer. I write at home, on a computer. I’m not using up any gasoline or motor oil, I’m not wearing out any clothing or shoes. To put it simply: I’m not a drain on the environment. (â€Å"You don’t move,† my wife observes, exaggerating slightly.) 18. BOARD UP THE WINDOWS. Windows are nice, but they either let in too much heat, or let out too much, or vice versa. (â€Å"This is better than mini-blinds!† I shout to the wife, who can barely hear me over her own hammering.) 1 9. GET RID OF THE TELEPHONE. Think you can’t live without a telephone? Think again. We’ve done fine. (â€Å"Who would call us?† my wife rationalizes.) 20. GET RID OF THE BED. Many leading chiropractors say that sleeping on the floor, with no mattress or cushion, is the best way to sleep. (â€Å"We certainly haven’t needed a bed much lately,† my wife confides to a mutual friend.) 21. GET OUT AND ORGANIZE. At my wife’s suggestion, I got out of the house and into the community—to organize. Now I work with a diverse group of community activists and we meet four times a week—at our house. (â€Å"Whoare these people?† my wife asks. â€Å"They are the people,† I tell her proudly.) 22. BAN ALL CHLOROFLUOROCARBONS. Not just spray cans, but the refrigerator and the air conditioner. Get rid of them! We now have ice delivered to our house every day. (â€Å"You’re crazy!† my wife shouts from the kitchen. â€Å"So was Van Gogh!† I shout back.) 23. TREAT WOUNDS NATURALLY. If you’re injured, cut on the head, above the eyebrow—from a sharp piece of ice, let’s say—treat it naturally. Salt and lemon juice is the combination my wife favors. (â€Å"I want a divorce,† she says, pouring salt on my wound. â€Å"Ouch!† I say.) 24. KNOW THE LAW. And know a good lawyer. (My wife does.) 25. WHEN YOU MOVE, BE A GOOD NEIGHBOR. Having recently relocated to a smaller environment—an apartment—I can empathize with anyone who has had to go through a â€Å"moving experience† as I call it. Remember, along with a new habitat come new co-inhabitants. Get to know them. They are your neighbors and, as simplistic as this sounds, they are the keys to your survival. (When I explain this simplistic theory to one of my new neighbors, she’s fascinated. Maybe the beard works!) 26. CARPOOL. At my new part-time job I carpool with a couple of the ladies from the office. We’re saving gas, money, and we’re getting to know each other better. (â€Å"He used to have a fear of intimacy,† my wife tells the judge. On the advice of Barry, my lawyer, I can say nothing.) 27. MAKE LOVE, NOT WAR. I know, I know. But, if I could just use one earth-saving tip to draw your attention to the beautiful and cosmic experience of making love with a truly giving and understanding sexual partner. (Takethat, you lying, blood-sucking witch!) 28. SHARE YOUR SHOWERS. I’ve done a complete one-eighty on this one. Use a kitchen timer. (Or Ravel’s Bolero!) 29. WOMEN! Or should I say, women judges! (This just in: She gets the car, the house—everything except the profits from this book, Dear Reader.) 30. YOU CAN MAKE A DIFFERENCE. When someone (especially someone much younger and less experienced than yourself that you only met two weeks ago) tells you that one person can’t make a difference—that no matter how much shouting and yelling and â€Å"whining and complaining† one person does nothing will change, that â€Å"you’re too old to be acting that way,† that â€Å"you should settle down and focus on one thing and do that well†Ã¢â‚¬â€when someone lays that trip on you, it’s time to split. (â€Å"I can make a difference!† I tell her, gathering my things.) 31. BUNDLE AND RECYCLE NEWSPAPERS. Sorry, I lost sight of what we’re trying to do here, which is save the earth. Take all your old newspapers, bundle them together, and bring them to a recycling center. They’ll give you a few bucks, which is nothing to sneeze at. (What happened?) 32. BUY A â€Å"RECYCLED† CAR. There are some good deals in used cars—if you take the time to look. (I didn’t, and boy am I sorry.) 33. DON’T LITTER THE HIGHWAYS. Be considerate. There are laws, but they’re rarely enforced. (Except in my case, of course. I told the officer I wasn’t living in my car—it had broken down, I was tired—but: A $100 fine for vagrancy, a night in jail, a towing charge of $75, and a ticket—I’m getting rid of this damn car!) 34. KEEP FIGHTING. That’s right. No matter how tough it gets, the fight to save the earth will go on, with or without you. (Right now it’s without. I’m back to my old habits again—smoking, drinking, and hanging out with a bunch of losers. One of them is a real nut, calls himself â€Å"The Master.†) 35. DONATE OLD CLOTHING. There are people out there who can get some good use out of your old moth-eaten sweater or sports jacket or worn-out pair of shoes. (I’m a 41 short.) 36. FOLLOW THE MASTER. The Master has forged an â€Å"alliance with the human spirit† that allows him to speak directly and simultaneously to every living thing on this planet. (Follow The Master.) 37. THINK FOR YOURSELF. Take it from someone who, after having his self-esteem obliterated by a persuasive con man and his gang of sycophants, escaped on foot—with nothing to eat for nine days but wild berries and mushrooms—and lived to talk about it! (You might have seen the story in the papers—†DAZED FOLLOWER OF DIZZY GURU FOUND ON FREEWAY†) 38. HI, HOW ARE YOU? I knew it was her before I picked up the phone. (The cobwebs that covered the receiver were now sticking to my face. â€Å"Fine,† I said.) 39. DON’T BE FOOLED. A wise consumer is a protected consumer. (I told my ex this when we got together for some Irish coffee at the mini-mall, near the old house. She ended up selling that barn for—get this—$650,000! â€Å"Honey, it seems like old times!† I whooped.) 40. RECYCLE! REVIVE! RERUN! Excuse my exuberance, but something is finally happening out there—something positive, something good. People are separating their garbage. They’re using biodegradable, ecologically safe, recyclable and reusable materials. Everything old is new again! (When my ex-wife and I decided to re-marry, I suggested a â€Å"Save the Earth† clause be added to our pre-nuptial agreement. â€Å"We have to talk,† she said, showing great interest at the time.) 41. MOVE TO THE COUNTRY. Inherit the land again. That’s what we did. Bought forty-three acres in Upstate New York. It’s a working farm, where my wife can go out to the barn and milk the cows, pick out the freshest eggs and knit our clothes from the wool she shears from our very own sheep. (And I can finish this book!)

Bonnie and Clyde Essays

Bonnie and Clyde Essays Bonnie and Clyde Paper Bonnie and Clyde Paper At first glance Bonnie and Clyde is a story of crime involving two equal parts, but after some examination it is clear that the film is very much a story exclusively about the character of Bonnie. Clyde and other characters act as foils for Bonnie and never fully develop in the same way that she does. Bonnie evolves as the story progresses, and although she is very masculinized, her initial immaturity dissipates with her characters confusion of gender identity. The film opens with an extreme close up of Bonnie putting lipstick on her lips, a very deliberate idea of femininity. However, she is bored and aimlessly wanders around her room naked; she peers outside and sees Clyde attempting to steal her mothers car. She confronts him and ultimately she is convinced to go with him to lead a life of freedom and excitement. Her role as the woman perpetuates her fascination with Clydes reckless masculine quality but the role becomes unnecessary and extraneous after he admits that he is impotent, or not much of a lover boy. She eventually accepts her role as equal companion to Clyde in his endeavors and becomes very satisfied with such. For instance, when trouble starts to brew Clyde warns Bonnie that she aint going to have a minutes peace, to which she simply responds, You promise? Later, in her foreshadowing poem that she reads to Clyde, shes admits to her self that death is the only means by which she will be relieved of the burdens of the life of crime she has chosen. Clyde in turn becomes excited by the poem realizing how their story would become legendary with its printing; his sexual ineptness is evidently cured and all of a sudden he wants to marry Bonny in the next scene. This is the most telling scene of Bonnies transformation back to a character that wants a civilized life; she asks Clyde if he would do anything differently if they could have it all back. Bonnie is noticeably disappointed when he responds superficially and without any regard to a different lifestyle which Bonnie now longs for. Bonnie is also significantly foiled against the films other female character, Bucks wife Blanche. Bonnie is very assertive and lively whereas Blanche is reserved and polite in the scene when they meet each other. Bonnie is quick to grab Clydes gun and pose in front of the car in a very masculine way for the camera. Blanche doesnt want her picture taken at all, and when its done anyway, it is just of her and Buck with their arms around each other. By this point in the film Bonnie is at her peak of masculine quality, she is surprised and disgusted at how reserved and manner-aware Blanche seems to be. When the gang is in the cabin and the police confront them, Bonnie responds as quickly as the three men do fend themselves off from the police officers. Blanche proceeds to only scream and run away from the loud guns and, as they escape, Blanche is practically left behind until she frantically runs after the vehicle; Bonnie is clearly one of the guys, a true part of the gang and Blanche is only an afterthought even to her husband Buck. Additionally, Bonnies character is the only one in the film that is shown as having a family who she wants to be with, with the exception of Buck and Clyde. C. W. Moss foils Bonnie in the sense that his father plays a significant role in the film, but he doesnt go to him until he needs help, and it is in the best interest of the whole gang. Bonnie longs to see her mother, an indication that she may miss her old life; it may have been boring but it was also meaningful and safe. She slowly become dissatisfied with the life she hastily chose when she met Clyde. She does go home to her mother with everyone but only after trying to run away from the gang in order to do so; she has become so dissatisfied with the life that she doesnt even bother to warn Clyde of her departure, not wanting to bring the gang into her family atmosphere. Both C.W. Moss father and Bonnies mother are disapproving of their behavior, but whereas Mrs. Parker reaffirms Bonnies need for something more, old man Moss feelings of Bonnie and Clyde and their way of life only causes C. W. Moss anger and a lack of understanding. Bonnie Parker is slowly transformed from restless female to a gun shooting, money loving, masculinized character. By the end of the film it is too late for her to transform back despite wanting nothing more; she realizes that any life with Clyde would be a nomadic life of crime and must accept her fate as a gangster as she wrote about it in her own poem. Ironically, Bonnie is the only character who both wants out of the life, but also realizes that such an opportunity is an impossibility.

Understanding SAT Scores What Do They Mean

Understanding SAT Scores What Do They Mean SAT / ACT Prep Online Guides and Tips You got your SAT score back, and you're not sure what to think of it. What does your SAT score mean? What does your SAT score measure? Is your SAT score high? Is it low? Will it get you into the college you hope to attend? I'll answer all of these questions below so you can start understanding SAT scores. What Does the SAT Measure? The SAT is supposed to measure your readiness for higher education and be a prediction of future academic success, thoughwhether it does measure so is debatable. There aremany smart, successful people, who don't do very well on the SAT. The SAT began as an Army IQ test, which was slightly altered and given as a college admissions test for the first time in 1926. However, the SAT did not become widespread until 1933, when the Harvard president began using it to judge scholarship applicants because he thought it was an accurate predictor of academic potential. By the 1940s, the SAT was the standard test among college applicants and was given to over 300,000 people in the US. What do SAT scores mean nowadays? Colleges continue to use the SAT because they see it and the ACT as â€Å"equalizers.† While every high school student across the country received a different education, all applicants take the SAT or ACT. Right or wrong, admissions officers see it as a fair way to compare students from across the globe. While what the SAT measures is debatable, the purpose of an SAT score isn’t. The purpose of your SAT score is to get you into college, so you should understand your SAT score in terms of how it can help you do that. How Does Your SAT Score Compare? SAT Score Range To understand your score, you need to know the range of possible SAT scores. If you already took the SAT or are taking the SAT this fall (2015), the composite scores can range from 600 to 2400. If you are taking the new SAT in spring 2016 or later, the composite scores can range from 400 to 1600. The average composite SAT score in the US is typically around 1500 (on the 2400 scale) though it varies slightly from year to year. The worst possible score (old test 600, new test 400) is very rare; only 374 students got this score in 2014, which is fewer than the 583 thatgot perfect scores (old test 2400, new test 1600). What’s a Good SAT Score in That Range? While we would all love a perfect score, it's unnecessary for most applicants. A good score for you depends on what college you hope to attend.To figure out if your score is â€Å"good† in terms of your target schools, search â€Å"[College Name] SAT.† That search should lead you to what's known as the Freshman Admit Profile. The name may vary slightly from school to school, but you should be able to find what's known as the 25th/75th percentile or the average SAT. The 25th percentile SAT score means that 25% of admits scored at or below (in other words, 75% of admitted applicants scored above). The 75th percentile SAT means that 75% of admits scored at or below (or 25% of admits scored above). The average SAT is an average of all of the admits’ SAT scores. A good score for that school is at or above the 75th percentile SAT score. If you reach that score and have a strong transcript and application, you'll have a great chance of getting in. For schools that only give the average SAT, I recommend aiming for a score 100 points higher than the average to ensure you are in the top 25% of students. Why should you aim for a higher score? In writing this, I'm assuming you are a typical applicant with no special qualification (recruited athlete, legacy, child of a significant donor, or a unique talent like a famous painter). Schools often accept students with special qualifications with lower scores. I think you should assume those students may account for as many as 25% of admits. If you're not one of those students, you want a higher SAT score to stand out, so aim for the 75th percentile or above. For further explanation, check out What is a good SAT score? A bad SAT score? An excellent SAT score? Should You Retest? How Many Times? If you did not meet the 75th percentile or above for your school of choice, I recommend retesting.However, you shouldn't take the SAT more than six times. If you haven't achieved your target score after three or four attempts, you're not preparing properly. You need to have a dedicated study plan to reach your goal. Check out one of our guides for sophomores, juniors, and seniors to creating an SAT study plan. Also, consider hiring an SAT tutor, taking an SAT class, or enrolling in an online SAT prep program such as PrepScholar. Created by Harvard grads and SAT full scorers, the program figures out your strengths and weaknesses, then customizes your preparation to your needs, so you get the most effective preparation possible. What’s Next? Need help with preparation? Struggling with the SAT Writing section? SAT Reading? SAT Math? Or just want overall SAT strategies? Remember, that with hard work and dedication you will achieve your desired score! Disappointed with your scores? Want to improve your SAT score by 240 points?We've written a guide about the top 5 strategies you must be using to have a shot at improving your score. Download it for free now:

3 Disagreements About How to Use Either and Neither

3 Disagreements About How to Use Either and Neither 3 Disagreements About How to Use â€Å"Either† and â€Å"Neither† 3 Disagreements About How to Use â€Å"Either† and â€Å"Neither† By Mark Nichol Use of either and neither, and their associated words or and nor, is complicated by disagreements about proper usage. Here’s a discussion of the words and the opinions about their appropriate use. An â€Å"either . . . or† or â€Å"neither . . . nor† construction can include more than two elements, but some grammar guides advise writers to restrict the usage to reference to two choices: â€Å"I’m going to wear either blue or green† but not â€Å"I’m going to wear either blue, green, or red.† If you agree with that restriction (I don’t), delete either from the latter sentence and it’s optional in the first one, for that matter. Omitting neither is not an option in the sentence â€Å"I’m going to wear neither blue nor green,† but the idea can also be rendered â€Å"I’m not going to wear blue or green.† The proscription against using or, rather than nor, with neither (â€Å"I was neither here or there† instead of â€Å"I was neither here nor there†) is likewise not absolute, but nor is most common, and in this case I support the restriction. The third divergence is about agreement with a verb. The more restrictive rule is that when either or neither is the subject, or part of the subject, of a sentence or a clause, it should be accompanied by a singular verb: â€Å"I don’t think either of the candidates is qualified.† When two nouns or pronouns are framed by either and or, use a singular verb if the noun or pronoun closest to the verb is singular (â€Å"Either the boys or the girl is responsible†) and a plural verb if the closest noun or pronoun is plural (â€Å"Either the girl or the boys are responsible†) or both nouns or pronouns are plural (â€Å"Either the girls or the boys are responsible†). However, it is common to see a plural verb with either or neither in reference to a sole plural noun or pronoun, as in â€Å"Neither of the parties are willing to compromise.† The more conservative choice is to write â€Å"Neither of the parties is willing to compromise,† and I adhere to that option. Here are several other considerations: When constructing an â€Å"either . . . or† or a â€Å"neither . . . nor† statement, take care to place verbs appropriately. If one verb applies to both choices, place it before the â€Å"either . . . or† phrase: â€Å"She was going to leave either tomorrow or Saturday.† If a separate verb applies to each choice, either should precede the first verb, and or should come before the second one: â€Å"She was going to either leave tomorrow or wait until Saturday.† Also, avoid using a â€Å"not . . . either† phrase, as in â€Å"They will not vote on either the amended proposal or the original one†; revise to a â€Å"neither . . . nor† construction: â€Å"They will vote on neither the amended proposal nor the original one.† Finally, a statement that two things are not true can also be rendered with a â€Å"never . . . nor† construction: â€Å"Their facility had never completed an evaluation nor ever met anyone representing the contracting agency.† Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Style category, check our popular posts, or choose a related post below:Direct and Indirect Objects26 Feel-Good WordsSentence Adverbs

Auteur theory Essay Example | Topics and Well Written Essays - 1500 words

Auteur theory - Essay Example Auteurism, or film analysis based on the idea of a directorial vision, grew out of his ideas. It spread to the United Kingdom, where the review Movie became its first primary practitioner. In the United States, Andrew Sarris introduced it in his 1962 essay â€Å"Notes on the Auteur Theory.† Sarris proposed some minimal requirements for a director to be considered an auteur: the director must demonstrate a level of competence in technique, evoke an individual style in terms of how a movie feels and looks, and even terms of overall theme. His work The American Cinema: Directors and Directions, 1929-1968, earned a reputation as the primary text for auteurism (Auteur theory). Auteurism has had its critics. Pauline Kael of The New Yorker objected to the idea of giving the director so much credit for a project that takes so many people to complete – not just the already mentioned scriptwriter, but the cinematographer as well. Also, auteurism can contribute greatly to the cost s of making a movie, and directors who develop a record of financial losses will not be able to bring a message of any kind to the big screen (Auteur theory). Also, New Criticism challenged auteur theory with its idea of the â€Å"intentional fallacy.† This referred to the idea that the words on a page of literature, or the images on a movie screen, are more important than the intentions of the author, or the intentions of the director. Because each viewer will approach a movie with a unique set of experiences and biases., the director's intention may never filter through the images and reach the mind of the viewer. In any discussion of directors who are considered auteurs, the name of Krzysztof Kieslowski comes to the forefront. Ironically, Kieslowski entered the study of film as a sort of detour on his original career path, which involved a desire to become a theater director. It was only when the College for Theater Technicians lacked a program for theater directors that he decided to study film as well (Krzysztof Kieslowski). Sieglohr posited that an auteur will see national identity as ripe fodder for "investigation and excavation" (Hill (Year) p. ). While Three Colors takes a look at the special significance of the three colors of the French flag, Kieslowski's early work took a look, as well, at the Polish national experience. As he studied film more extensively, he decided to make documentaries rather than directing plays. His first projects focused on the daily routines of workers, soldiers, and other citizens. However, even though Kieslowski's intentions were not to make political statements, even his attempts to depict the lives of Polish citizens realistically ran afoul of the censoring

Case study Example | Topics and Well Written Essays - 750 words - 12

Case Study Example That is, African Americans trying to rent an apartment can expect to encounter race discrimination at nearly one-third of the city’s apartment complexes, according to a city-funded study. Roughly 30 of 100 apartment complexes in the study were found to give â€Å"preferential treatment† to whites over African Americans who sought information on apartment availability and price. Regardless of evidence provided or allegations placed against an individual, all suspects are innocent until proven guilty. Thus, despite the fact that all facts and evidences are pointing towards Peters, my assumptions while working on this case was that as far as Square Deal Housing had evidence against Peters, Peters was innocent until when he will be proven guilty by the court. In order to analyze this information I used Box and Whisker Plot as the main analysis tool. Box and Whisker Plot is a data and information analysis tool used to show and analyze multiple sets of variation data on a single graph. After critical analysis of this case, I found that Square Deal Housing’s allegations against Peters were right and with sufficient roof, and that Peters had actually violated â€Å"Fair Share† rule. Hence, I advised him accordingly. What I can recommend for management is that they should adhere to â€Å"fair share† of the metropolitan area’s African American tenants. They should not use inability of African Americans to ay rents on time as excuse. That is, they should give all people equal chances regardless of their race or

Compare and contrast two opposite cases where Web 2.0 tools have been Essay

Compare and contrast two opposite cases where Web 2.0 tools have been used to build an identity and encourage participation, and explain why you think one was successful and the other wasnt - Essay Example What is common in both the viewpoints is the idea that the new developments in information and communication technologies certainly change the way we interact, civic engagement and community creation. The participation has the ability and potential to make the difference. The awareness about the possibilities of participation is a defining feature of the present democratic societies. â€Å"The crisis of political participation† is the product of the dilemmas of this awareness on participation (Bryan, Tsagarousianou and Tambini, 1998, p. 3). However, more electronic democracy could only be achieved through universal availability of internet and open discourses on internet. According to Bryan, Tsagarousianou and Tambini (1998), although access to information network is a public right, the cost and private ownership of such infrastructure and technologies lead to a tension between both. Bughin, Chui, and Johnson have asserted that â€Å"companies will need a combination of incentives of encourage customer participation† (2008, p.28). In the case study of Coloplast’s web supported community of health care practitioners, it has been found that â€Å"web communities in the professional market build on preexisting communities, enabling community members to intensify the activities of the community to expand its reach† (Andersen, 2005, p. 49). It could be seen as an example of identity building and community creation. In the content analysis of the sites and blogs for the 10 Democratic candidates in the 2004 US presidential election, it has been revealed that â€Å"candidates promoted interactivity online through technical means such as enabling asynchronous feedback in blog comments as well as fostering an environment of participation through textual appeals and strategy† (Trammel, 2006, p.42). Here, there in no actual participation, just networking for the purpose of vote

Theory on selected topics Essay Example | Topics and Well Written Essays - 1500 words

Theory on selected topics - Essay Example These products are usually categorized according to their characteristics of market growth rate and market share. A typical BCG matrix is shown in the figure below: As we all know that McDonald’s Corporation is made up of world-wide business, such as McDonald’s USA, McDonald’s Europe, McDonald’s Asia and McDonald’s America. We are going to use the lens of BCG matrix to determine the position of each of these businesses in a BCG matrix for McDonald’s Corporation. (QuickMBA, 2009) STARS: Stars are those products that have a large market share in a rapidly growing industry. In simple words, these are successful products that need continuous investment to maintain their dominating position in the market. According to the statistics given in McDonald’s Corporation’s annual report, McDonald’s USA is a star. It has a high market share in the market which is booming rapidly. However, due to increased competition in the market, McDonald’s Corporation should invest in McDonald’s USA heavily, so that they do not lose out market share to other competitors like Burger King or KFC. (Daft, 1997). A question-mark is a business that has low-market share in the rapidly growing industry. In order to increase the market share, the business will need more and more resources. However, it is not guaranteed that the business has enough potential to become a start. In the case of McDonald’s corporation, McDonald’s Europe falls under the category of a BCG Matrix â€Å"Question Mark†. McDonald’s Europe has found it tough to break into the food industry which is already congested with various firms in the industry. The culture diversification in the different parts of Europe has also resulted in low-demands and cash returns for McDonald’s Europe, making it a question mark. The only way to cure the problem is that McDonald should carry out a market research to find out what people

Assignment 2 Example | Topics and Well Written Essays - 3000 words

2 - Assignment Example The McWane Story included various issues which are contrary to the obligations and requirements of a good employer. This include important problems and issues with the balance between profitability and the requirement for ethics in relation to social and environmental matters that culminated into health and safety issues and major employment challenges that led to important and serious problems for the employees of the organization. Primarily, McWane was fundamentally involved in ensuring that profitability was at the center of its practice and its operations. This includes the focus on profits rather than other issues and matters like working with sensitivity and concerns for employees and workers. This led to a strong desire and a strong quest for attaining profits without concerning workers of the plant. OSHA Rules have various requirements for employers like McWane. This includes the fact that employers are required to follow health and safety in protecting employees in dealing with their work. However, McWane’s Tyler Pipes plant was one that overlooked numerous processes and systems that was necessary to improve profitability. However, this process was limited because the firm focused significantly on profits without concerning themselves with the demands and expectations of workers. Safety was sacrificed for meeting productivity targets and for ensuring that workers continue to attain important results and important ends. This led to numerous accidents and processes that led to important processes and systems. The management practices and processes of McWane were such that workers were required and expected to adhere to strict management practices and standards. The implication was that the managers had to overlook important employment statutes including some Common Law and other legal requirements for the regulation of employee

Theory on selected topics Essay Example | Topics and Well Written Essays - 1500 words

Theory on selected topics - Essay Example These products are usually categorized according to their characteristics of market growth rate and market share. A typical BCG matrix is shown in the figure below: As we all know that McDonald’s Corporation is made up of world-wide business, such as McDonald’s USA, McDonald’s Europe, McDonald’s Asia and McDonald’s America. We are going to use the lens of BCG matrix to determine the position of each of these businesses in a BCG matrix for McDonald’s Corporation. (QuickMBA, 2009) STARS: Stars are those products that have a large market share in a rapidly growing industry. In simple words, these are successful products that need continuous investment to maintain their dominating position in the market. According to the statistics given in McDonald’s Corporation’s annual report, McDonald’s USA is a star. It has a high market share in the market which is booming rapidly. However, due to increased competition in the market, McDonald’s Corporation should invest in McDonald’s USA heavily, so that they do not lose out market share to other competitors like Burger King or KFC. (Daft, 1997). A question-mark is a business that has low-market share in the rapidly growing industry. In order to increase the market share, the business will need more and more resources. However, it is not guaranteed that the business has enough potential to become a start. In the case of McDonald’s corporation, McDonald’s Europe falls under the category of a BCG Matrix â€Å"Question Mark†. McDonald’s Europe has found it tough to break into the food industry which is already congested with various firms in the industry. The culture diversification in the different parts of Europe has also resulted in low-demands and cash returns for McDonald’s Europe, making it a question mark. The only way to cure the problem is that McDonald should carry out a market research to find out what people

Organizational change in the face of profitability drop in McDonalds Essay

Organizational change in the face of profitability drop in McDonalds Corporation - Essay Example It is evidently clear from the discussion that it is undisputable fact that change is inevitable and one of the most fundamental processes of any organization. Presently, than ever before, organizations face rapid change. Globalization and increased expectations of customers and employees, competition, technological advancements, and need to boost profitability is what have made change to be inevitable in organizations. Besides, more concern by stakeholders of organizations has prompted the management to adopt change strategies in order to convince the stakeholders that they are capable of achieving the organizational objectives. However, various studies have shown that despite the fact that change is inevitable and most companies management are planning and implementing change, the process of managing change is proving a great challenge. According to Isern and Pung, leaders rarely achieve their objectives when they have embarked on a major effort of change in their respective organi zations. They note that there are factors that distinguish successful and unsuccessful efforts to change. They argue that a true transformation within an organization is characterized by integration of different change types (commercial, operational, and organizational), sustained effort that last for longer periods, and high ambitions. Isern and Pung further note that numerous surveys have shown that have difficulty achieving intended results. According to a 2006 online survey by McKinsey Quarterly only 38 percent of the executives across the globe who responded reported to have had a complete success on the transformations they instituted in their organizations. A tenth of those who responded acknowledged that their organizational transformation efforts were completely unsuccessful (Isern and Pung, 2007, p.1). It is in the light of this that this discussion will critically evaluate using appropriate models, theories and practical interventions how a manager can successfully manage a ‘radical change’ within a complex organization. The evaluation will focus on radical change in regard to aspects such as a sharp drop or slide in profitability. The discussion will assess organizational change in the face of profitability drop in McDonald’s Corporation. Change Model Managing radical change within an organization may not be an easy task as various surveys have shown. Radical change may be prompted by various circumstances such as enticing new customers, fighting competition, and sharp drop in profitability. Since managing change needs to be done appropriately in order to be successful, it is important that certain model or models be adopted. In this case, and in particular reference to managing change in the face of drop of McDonald’s profitability, Kotter’s 8- Step Change Model will be used. Kotter (1996, p. 26) states the first step in managing change is through creation of urgency. Change will be of help to the company if the c ompany really wants it; therefore, there is need for development of sense of urgency. Burnes (2009, p.103) agrees with Kotter’s proposition of creation of urgency around a need by arguing that it is essential in motivating employees in the organization to get things moving. According to Kotter, creation of urgency entails the following; examining opportunities that can and should be exploited, identifying potential threats and developing scenarios of possible future happenings, giving of convincing and dynamic reasons so that people can talk and think about them, and requesting support of stakeholders, industry players, and customers so as to strengthen the argument about change. McDonald’

Computer Technology Essay Example for Free

Computer Technology Essay The education system world wide has been vying to raise the quality of education as reflected in the volumes of research regarding quality education and teacher effectiveness. In the light of the rapid advancement of technology, more research attention has been given to the integration of information and computer technology (ICT) with the educational design and curriculum. It has been included for since computers were invented, however because of the rapid rate by which modernization occurs, the ministries of education for every country must be able to cope up by intensifying the rate degree of integration while upholding quality content and instruction as well. In present Saudi Arabia, the application of satellite technology had been the focused issue because of its potential to elevate the quality of teaching and learning at all levels (Al-Sharhan 2000). Studies have shown Australian states as a model for the significant links communication systems provide for students across the nation to interact and add valuable substance to their learning (Al-Sharhan 2000). The potential of such satellite communication new instated in Saudi Arabia and its uses for educational purpose is yet an area to be discovered and studied because of the reduced equipment, maintenance and operational cause that this technological advancement provides (Al-Sharhan 2000). However, the education system in Saudi Arabia must be prepared by properly equipping their teachers, their curriculum, and their students for the changes that would occur as the operation of the satellite communication are full-fledged. The important focus of this management plan is to introduce ICT and integrate it into the method of quality teaching and learning to the highest degree possible. In ten years time the great need to close the â€Å"performance gap† between the schools and colleges in terms of achieving the goals of a world class high quality education would be eradicated if not it would totally minimal compared to the global leaders in education (Kelly 2001). The current status of the education system defined by limited technology. Studies are still underway into how the satellites can be used however, at present; there are still no clear terms in how it must be used before this quality teaching and learning framework. Planning for improvement must be based upon the baseline or the â€Å"initial audit† of the school and college to include the opinions of the parents, the students, and the staff as the starting point for quality management (Kelly 2001). Considerations must be a unified expected outcome, the welfare of the internal customers, the key persons responsible for implementation and task assignments and a means to assess and evaluate the effectiveness of the plan (Kelly 2001). Overview There must be a close consideration for the content and educational design for the integration of ICT into the curriculum and into the classroom instruction (Naidu 2003). Content refers to the information or in the scenario of the ICT integration, electronic information that the students would get as learners (Naidu 2003). Educational design refers to the processes that the educators would use in planning and providing the education for the students (Naidu 2003). The faculty needs to be prepared and guided for the integration of the technology. As the method of instruction would be elevated and modernized, the teaching quality must be improved as well and not be forgotten in the excitement for advanced technology (Fraser 2004). Regulatory and quality assurance would be increased, however there would be a shift from a managerial system to an academic accountability system for the teachers in the college as they have more freedom as well as responsibility when their methods for instruction grows wider (Fraser 2004). The increased emphasis on quality and accountability would be a response to the changes that the colleges and universities would have with a change in their material conditions as the satellite technology become fully accessible and utilized in education (Fraser 2004). As most teachers are used to the traditional technologies, they must be aware that every tool that would become available has something unique and valuable to offer (Clark et al. 2003). Technology can enrich any course subject in ways the traditional method cannot (Clark et al. 2003). In terms of assessment such ICT programs, a web-based assessment reflects the continuum of assessment types because of their nature of improvement (Naidu 2003). Traditional assessments were known to lack a variety and autonomy as well as student choice, they were also lacking in work-based application and project-based learning as well as limited peer and self-assessment strategies (Naidu 2003). ICT-based assessments would be introduced in this plan to be able to evaluate the quality of an ICT-integrated education system. Satellite communications are used for different applications that can both be used for educational purposes; one is for remote sensing, taking pictures and capturing scientific data and the other for telecommunication purposes (Al-Sharhan 2000). Their difference in purpose can point to different themes and school activities by which they would be used. The telephone link would be one of the most important contributions this satellite technology can have for the schools of Saudi Arabia (Al-Sharhan 2000). Theoretical Foundations Expected Outcome Teachers. The computer and all the benefits it can provide have been massively changing the perception for teaching instruction (Nicholls 2002). The expectations have become higher in terms of teacher preparation and delivery in relation to quality education (Nicholls 2002). The teachers can not be one way or the other when it comes to technology; most of the time, some either ignore technology because of the lack of trust and knowledge or rely on them because of familiarity (Nicholls 2002). The implementation of this plan would enable the teachers to be comfortable with teaching with technology. In less than ten years, the staff would become so familiar with ICT that it would be the new normalcy when it comes to quality education. The elevation of standard for the Saudi Arabia schools would reflect that not only a few subjects would make use of such ICT-based curriculum, but it would be a requirement for every subject course and professor. The educators would be the ones introducing technological advancement to their students with their methods and in turn the students would be equipped to use them because of such instruction. Students. The satellite technology would be able to accommodate a large number of students simultaneously and over an extended geographical area (Al-Sharhan 2000). Most of the students are more IT literate and expect technology to be used for teaching by the educators (Nicholls 2002). The teachers, who are well-equipped in operating technology, would be able to customize their activities to fit the needs of the students. It encourages the students to go beyond the lecture to expand their learning and to conduct self-directed study (Nicholls 2002). The school may have web-based discussion forums, electronic mailing lists that enhance student participation and individualized learning (Nichols 2002). The Education System. The integration of ICT and the use of satellite technology can be potential for elevating the standard of the education system in developing countries to overcome specific problems such as loosing high quality teachers due to emigration to other countries, shortage of physical equipment and materials in many schools (Al-Sharhan 2000). The combat against high adult literacy can also be fought better given the Open University potential for online learning (Al-Sharhan 2000). It also provides the solution for segregating male and female students that would be difficult in physical classrooms but would be possible with online classrooms that would give more educational opportunities to women than before (Al-Sharhan 2000).

Polyisobutylene Applications

Polyisobutylene Applications Fuel and lubricant additive. Polyisobutylene (in the form of polyisobutylene succinimide) has interesting properties when used as an additive in lubricating oils and motor fuels. Polyisobutylene added in small amounts to the lubricating oils used in machining results in a significant reduction in the generation of oil mist and thus reduces the operators inhalation of oil mist.[2] It is also used to clean up waterborne oil spills as part of the commercial product Elastol. When added to crude oil it increases the oils viscoelasticity when pulled, causing the oil to resist breakup when it is vacuumed from the surface of the water. As a fuel additive, polyisobutylene has detergent properties. When added to diesel fuel, it resists fouling of fuel injectors, leading to reduced hydrocarbon and particulate emissions.[3] It is blended with other detergents and additives to make a detergent package that is added to gasoline and diesel fuel to resist buildup of deposits and engine knock.[4] Polyisobutylene is used in some formulations as a thickening agent. [edit]Sporting equipment Butyl rubber is used for the bladders in basketballs, footballs, soccer balls and other inflatable balls to provide a tough, airtight inner compartment. [edit]Roof Repair Butyl rubber sealant is used for rubber roof repair and for maintenance of roof membranes (especially around the edges). It is important to have the roof membrane fixed, as a lot of fixtures (i.e., air conditioner vents, plumbing and other pipes, etc.) can considerably loosen it. Rubber roofing typically refers to a specific type of roofing materials that are made of ethylene propylene diene monomers (EPDM). It is crucial to the integrity of such roofs to avoid using harsh abrasive materials and petroleum-based solvents for their maintenance. Polyester fabric laminated to butyl rubber binder provides a single-sided waterproof tape that can be used on metal, PVC, and cement joints. It is ideal for repairing and waterproofing metal roofs. [edit]Gas masks and chemical agent protection Butyl rubber is one of the most robust elastomers when subjected to chemical warfare agents and decontamination materials. It is a harder and less porous material than other elastomers, such as natural rubber or silicone, but still has enough elasticity to form an airtight seal. While butyl rubber will break down when exposed to agents such as NH3 (ammonia) or certain solvents, it breaks down more slowly than comparable elastomers. It is therefore used to create seals in gas masks and other protective clothing. [edit]Chewing gum Molecular structure: Rubber Chemical Structure Introduction to rubber chemical structure: In the organic chemistry section of chemistry ,we learn about the various polymers , monomers,elastomers etc.Monomer is a single unit and when huge number of monomers are combined or say polymerised then polymers are formed.The process of conversion of monomer to polymer is known as p-olymerisation.Elastomer is an another category of polymers having a specific properties of regaining of its structure even if it is stretched.Rubber comes under the category of elastomer.In general life rubber has variety of uses.the important property of rubber is that it regains its structure even if it is stretched.Stretching can be done up to a certain limit.If it is stretched beyond limit then it can break. Rubber can be found in two forms 1)Natural rubber 2)Synthetic Rubber Natural rubber is a kind of rubber which which is found directly from the nature.And when the natural rubber is processed under some chemical processes then a new kind of rubber is formed ,this rubber is known as synthetic rubber.We can also say that natural rubber are synthesised from the natural rubber.Both this rubber are of great use because of its specific features. Structure of rubber: Main composition of crude rubber is hydrocarbons.It also contains some proteins and materials which are soluble in acetone.The hydrocarbons which possess the properties of rubber are usually high in molecular weight and it ranges from 45000 to 3000000.Isoprene is a monomer of natural rubber.When huge number of isoprene units are polymerised then a polymer is formed . Cis and Trans Configuration of Rubber The cis configuration of the natural rubber is the reason for the rubber properties in it. Cis configuration means that extension of the chain is on the same side of the ethylene bond.If the configuration is trans, it means that the extension of chain is on the both sides of ethylene bond,then it is a hard plastic.In case of trans it does not show the properties of rubber. Synthetic rubber is of great use in the industry.Some of the widely used synthetic rubber are butyl rubber which is formed by the copolymerisation of isobutylene and a little amount isoprene.Another synthetic rubber is Styrene Butadiene Rubber also known as SBR.Buna N and buna S is also a kind of synthetic rubber often use in the industry. Vulcanisation of Rubber In the rubber molecules the cross linking between the chains are very less.This leads to the softness in the rubber .To make the rubber hard some chemicals are added to it.The process is known as vulcanisation.In this process the natural rubber is treated with some chemicals ,more often chemical used is sulphur.When sulphur reacts with the natural rubber then it increases the cross linking between the molecules in the rubber.It also forms many sulphide bonds.Due to formation of many new crosslinkings and many sulphide bonds the natural rubber becomes hard.Natural rubber is a kind of thermoplastic,it means that it becomes soft when it is subjected to heat and it becomes hard when it is subjected to cold. butyl rubber (IIR), also called isobutylene-isoprene rubber, a synthetic rubber produced by copolymerizing isobutylene with small amounts of isoprene. Valued for its chemical inertness, impermeability to gases, and weatherability, butyl rubber is employed in the inner linings of automobile tires and in other specialty applications. Both isobutylene (C[CH3]2=CH2) and isoprene (CH2=C[CH3]-CH=CH2) are usually obtained by the thermal cracking of natural gas or of the lighter fractions of crude oil. At normal temperature and pressure isobutylene is a gas and isoprene is a volatile liquid. For processing into IIR, isobutylene, refrigerated to very low temperatures (approximately à ¢Ã‹â€ Ã¢â‚¬â„¢100  °C [à ¢Ã‹â€ Ã¢â‚¬â„¢150  °F]), is diluted with methyl chloride. Low concentrations (1.5 to 4.5 percent) of isoprene are added in the presence of aluminum chloride, which initiates the reaction in which the two compounds copolymerize (i.e., their single-unit molecules link together to form giant, multiple-unit molecules). The polymer repeating units have the following structures: Because the base polymer, polyisobutylene, is stereoregular (i.e., its pendant groups are arranged in a regular order along the polymer chains) and because the chains crystallize rapidly on stretching, IIR containing only a small amount of isoprene is as strong as natural rubber. In addition, because the copolymer contains few unsaturated groups (represented by the carbon-carbon double bond located in each isoprene repeating unit), IIR is relatively resistant to oxidation-a process by which oxygen in the atmosphere reacts with the double bonds and breaks the polymer chains, thereby degrading the material. Butyl rubber also shows an unusually low rate of molecular motion well above the glass transition temperature (the temperature above which the molecules are no longer frozen in a rigid,glassy state). This lack of motion is reflected in the copolymers unusually low permeability to gases as well as in its outstanding resistance to attack by ozone. The copolymer is recovered from the solvent as a crumb, which can be compounded with fillers and other modifiers and then vulcanized into practical rubber products. Owing to its excellent air retention, butyl rubber is the preferred material for inner tubes in all but the largest sizes. It also plays an important part in the inner liners of tubeless tires. (Because of poor tread durability, all-butyl tires have not proved successful.) IIR is also used for many other automobile components, including window strips, because of its resistance to oxidation. Its resistance to heat has made it indispensable in tire manufacture, where it forms the bladders that retain the steam or hot water used to vulcanize tires. Bromine or chlorine can be added to the small isoprene fraction of IIR to make BIIR or CIIR (known as halobutyls). The properties of these polymers are similar to those of IIR, but they can be cured more rapidly and with different and smaller amounts of curative agents. As a result, BIIR and CIIR can be cocured more readily in contact with other elastomers making up a rubber product. Butyl rubber was first produced by American chemists William Sparks and Robert Thomas at the Standard Oil Company of New Jersey (nowExxon Corporation) in 1937. Earlier attempts to produce synthetic rubbers had involved the polymerization of dienes (hydrocarbon molecules containing two carbon-carbon double bonds) such as isoprene and butadiene. Sparks and Thomas defied convention by copolymerizing isobutylene, an olefin (hydrocarbon molecules containing only one carbon-carbon double bond) with small amounts-e.g., less than 2 percent-of isoprene. As a diene, isoprene provided the extra double bond required to cross-link the otherwise inert polymer chains, which were essentially polyisobutylene. Before experimental difficulties were resolved, butyl rubber was called futile butyl, but with improvements it enjoyed wide acceptance for its low permeability to gases and its excellent resistance to oxygen and ozone at normal temperatures. During World War IIthe copolymer was called GR-I, for Government Rubber-Isobutylene. LINKS Related Articles Top of Form Polymers 1. Introduction Prior to the early 1920s, chemists doubted the existence of molecules having molecular weights greater than a few thousand. This limiting view was challenged by Hermann Staudinger, a German chemist with experience in studying natural compounds such as rubber and cellulose. In contrast to the prevailing rationalization of these substances as aggregates of small molecules, Staudinger proposed they were made up of macromolecules composed of 10,000 or more atoms. He formulated a polymeric structure for rubber, based on a repeating isoprene unit (referred to as a monomer). For his contributions to chemistry, Staudinger received the 1953 Nobel Prize. The terms polymer and monomer were derived from the Greek roots poly (many), mono (one) and meros (part). Recognition that polymeric macromolecules make up many important natural materials was followed by the creation of synthetic analogs having a variety of properties. Indeed, applications of these materials as fibers, flexible films, adhesives, resistant paints and tough but light solids have transformed modern society. Some important examples of these substances are discussed in the following sections. art 2. Writing Formulas for Polymeric Macromolecules The repeating structural unit of most simple polymers not only reflects the monomer(s) from which the polymers are constructed, but also provides a concise means for drawing structures to represent these macromolecules. For polyethylene, arguably the simplest polymer, this is demonstrated by the following equation. Here ethylene (ethene) is the monomer, and the corresponding linear polymer is called high-density polyethylene (HDPE). HDPE is composed of macromolecules in which n ranges from 10,000 to 100,000 (molecular weight 2*105 to 3 *106 ). If Y and Z represent moles of monomer and polymer respectively, Z is approximately 10-5 Y. This polymer is called polyethylene rather than polymethylene, (-CH2-)n, because ethylene is a stable compound (methylene is not), and it also serves as the synthetic precursor of the polymer. The two open bonds remaining at the ends of the long chain of carbons (colored magenta) are normally not specified, because the atoms or groups found there depend on the chemical process used for polymerization. The synthetic methods used to prepare this and other polymers will be described later in this chapter. Unlike simpler pure compounds, most polymers are not composed of identical molecules. The HDPE molecules, for example, are all long carbon chains, but the lengths may vary by thousands of monomer units. Because of this, polymer molecular weights are usually given as averages. Two experimentally determined values are common: Mn , the number average molecular weight, is calculated from the mole fraction distribution of different sized molecules in a sample, and Mw , the weight average molecular weight, is calculated from the weight fraction distribution of different sized molecules. These are defined below. Since larger molecules in a sample weigh more than smaller molecules, the weight average Mw is necessarily skewed to higher values, and is always greater than Mn. As the weight dispersion of molecules in a sample narrows, Mw approaches Mn, and in the unlikely case that all the polymer molecules have identical weights (a pure mono-disperse sample), the ratio Mw / Mn becomes unity. The influence of different mass distributions on Mn and Mw may be examined with the aid of a simple mass calculator. To use this device Click Here. Many polymeric materials having chain-like structures similar to polyethylene are known. Polymers formed by a straightforward linking together of monomer units, with no loss or gain of material, are called addition polymers or chain-growth polymers. A listing of some important addition polymers and their monomer precursors is presented in the following table. Some Common Addition Polymers Name(s) Formula Monomer Properties Uses Polyethylene low density (LDPE) -(CH2-CH2)n- ethylene CH2=CH2 soft, waxy solid film wrap, plastic bags Polyethylene high density (HDPE) -(CH2-CH2)n- ethylene CH2=CH2 rigid, translucent solid electrical insulation bottles, toys Polypropylene (PP) different grades -[CH2-CH(CH3)]n- propylene CH2=CHCH3 atactic: soft, elastic solid isotactic: hard, strong solid similar to LDPE carpet, upholstery Poly(vinyl chloride) (PVC) -(CH2-CHCl)n- vinyl chloride CH2=CHCl strong rigid solid pipes, siding, flooring Poly(vinylidene chloride) (Saran A) -(CH2-CCl2)n- vinylidene chloride CH2=CCl2 dense, high-melting solid seat covers, films Polystyrene (PS) -[CH2-CH(C6H5)]n- styrene CH2=CHC6H5 hard, rigid, clear solid soluble in organic solvents toys, cabinets packaging (foamed) Polyacrylonitrile (PAN, Orlon, Acrilan) -(CH2-CHCN)n- acrylonitrile CH2=CHCN high-melting solid soluble in organic solvents rugs, blankets clothing Polytetrafluoroethylene (PTFE, Teflon) -(CF2-CF2)n- tetrafluoroethylene CF2=CF2 resistant, smooth solid non-stick surfaces electrical insulation Poly(methyl methacrylate) (PMMA, Lucite, Plexiglas) -[CH2-C(CH3)CO2CH3]n- methyl methacrylate CH2=C(CH3)CO2CH3 hard, transparent solid lighting covers, signs skylights Poly(vinyl acetate) (PVAc) -(CH2-CHOCOCH3)n- vinyl acetate CH2=CHOCOCH3 soft, sticky solid latex paints, adhesives cis-Polyisoprene natural rubber -[CH2-CH=C(CH3)-CH2]n- isoprene CH2=CH-C(CH3)=CH2 soft, sticky solid requires vulcanization for practical use Polychloroprene (cis + trans) (Neoprene) -[CH2-CH=CCl-CH2]n- chloroprene CH2=CH-CCl=CH2 tough, rubbery solid synthetic rubber oil resistant 3. Properties of Macromolecules A comparison of the properties of polyethylene (both LDPE HDPE) with the natural polymers rubber and cellulose is instructive. As noted above, synthetic HDPE macromolecules have masses ranging from 105 to 106 amu (LDPE molecules are more than a hundred times smaller). Rubber and cellulose molecules have similar mass ranges, but fewer monomer units because of the monomers larger size. The physical properties of these three polymeric substances differ from each other, and of course from their monomers. à ¢Ã¢â€š ¬Ã‚ ¢ HDPE is a rigid translucent solid which softens on heating above 100 ° C, and can be fashioned into various forms including films. It is not as easily stretched and deformed as is LDPE. HDPE is insoluble in water and most organic solvents, although some swelling may occur on immersion in the latter. HDPE is an excellent electrical insulator. à ¢Ã¢â€š ¬Ã‚ ¢ LDPE is a soft translucent solid which deforms badly above 75 ° C. Films made from LDPE stretch easily and are commonly used for wrapping. LDPE is insoluble in water, but softens and swells on exposure to hydrocarbon solvents. Both LDPE and HDPE become brittle at very low temperatures (below -80 ° C). Ethylene, the common monomer for these polymers, is a low boiling (-104 ° C) gas. à ¢Ã¢â€š ¬Ã‚ ¢ Natural (latex) rubber is an opaque, soft, easily deformable solid that becomes sticky when heated (above. 60 ° C), and brittle when cooled below -50 ° C. It swells to more than double its size in nonpolar organic solvents like toluene, eventually dissolving, but is impermeable to water. The C5H8 monomer isoprene is a volatile liquid (b.p. 34 ° C). à ¢Ã¢â€š ¬Ã‚ ¢ Pure cellulose, in the form of cotton, is a soft flexible fiber, essentially unchanged by variations in temperature ranging from -70 to 80 ° C. Cotton absorbs water readily, but is unaffected by immersion in toluene or most other organic solvents. Cellulose fibers may be bent and twisted, but do not stretch much before breaking. The monomer of cellulose is the C6H12O6aldohexose D-glucose. Glucose is a water soluble solid melting below 150 ° C. To account for the differences noted here we need to consider the nature of the aggregate macromolecular structure, or morphology, of each substance. Because polymer molecules are so large, they generally pack together in a non-uniform fashion, with ordered or crystalline-like regions mixed together with disordered or amorphous domains. In some cases the entire solid may be amorphous, composed entirely of coiled and tangled macromolecular chains. Crystallinity occurs when linear polymer chains are structurally oriented in a uniform three-dimensional matrix. In the diagram on the right, crystalline domains are colored blue. Increased crystallinity is associated with an increase in rigidity, tensile strength and opacity (due to light scattering). Amorphous polymers are usually less rigid, weaker and more easily deformed. They are often transparent. Three factors that influence the degree of crystallinity are: i) Chain length ii) Chain branching iii) Interchain bonding The importance of the first two factors is nicely illustrated by the differences between LDPE and HDPE. As noted earlier, HDPE is composed of very long unbranched hydrocarbon chains. These pack together easily in crystalline domains that alternate with amorphous segments, and the resulting material, while relatively strong and stiff, retains a degree of flexibility. In contrast, LDPE is composed of smaller and more highly branched chains which do not easily adopt crystalline structures. This material is therefore softer, weaker, less dense and more easily deformed than HDPE. As a rule, mechanical properties such as ductility, tensile strength, and hardness rise and eventually level off with increasing chain length. The nature of cellulose supports the above analysis and demonstrates the importance of the third factor (iii). To begin with, cellulose chains easily adopt a stable rod-like conformation. These molecules align themselves side by side into fibers that are stabilized by inter-chain hydrogen bonding between the three hydroxyl groups on each monomer unit. Consequently, crystallinity is high and the cellulose molecules do not move or slip relative to each other. The high concentration of hydroxyl groups also accounts for the facile absorption of water that is characteristic of cotton. Natural rubber is a completely amorphous polymer. Unfortunately, the potentially useful properties of raw latex rubber are limited by temperature dependence; however, these properties can be modified by chemical change. The cis-double bonds in the hydrocarbon chain provide planar segments that stiffen, but do not straighten the chain. If these rigid segments are completely removed by hydrogenation (H2 Pt catalyst), the chains lose all constrainment, and the product is a low melting paraffin-like semisolid of little value. If instead, the chains of rubber molecules are slightly cross-linked by sulfur atoms, a process called vulcanization which was discovered by Charles Goodyear in 1839, the desirable elastomeric properties of rubber are substantially improved. At 2 to 3% crosslinking a useful soft rubber, that no longer suffers stickiness and brittleness problems on heating and cooling, is obtained. At 25 to 35% crosslinking a rigid hard rubber product is formed. The following illust ration shows a cross-linked section of amorphous rubber. By clicking on the diagram it will change to a display of the corresponding stretched section. The more highly-ordered chains in the stretched conformation are entropically unstable and return to their original coiled state when allowed to relax (click a second time). On heating or cooling most polymers undergo thermal transitions that provide insight into their morphology. These are defined as the melt transition, Tm , and the glass transition, Tg . Tm is the temperature at which crystalline domains lose their structure, or melt. As crystallinity increases, so does Tm. Tg is the temperature below which amorphous domains lose the structural mobility of the polymer chains and become rigid glasses. Tg often depends on the history of the sample, particularly previous heat treatment, mechanical manipulation and annealing. It is sometimes interpreted as the temperature above which significant portions of polymer chains are able to slide past each other in response to an applied force. The introduction of relatively large and stiff substituents (such as benzene rings) will interfere with this chain movement, thus increasing Tg (note polystyrene below). The introduction of small molecular compounds called plasticizers into the polymer matrix increases the interchain spacing, allowing chain movement at lower temperatures. with a resulting decrease in Tg. The outgassing of plasticizers used to modify interior plastic components of automobiles produces the new-car smell to which we are accustomed. Tm and Tg values for some common addition polymers are listed below. Note that cellulose has neither a Tm nor a Tg. Polymer LDPE HDPE PP PVC PS PAN PTFE PMMA Rubber Tm ( °C) 110 130 175 180 175 >200 330 180 30 Tg ( °C) _110 _100 _10 80 90 95 _110 105 _70 Rubber is a member of an important group of polymers called elastomers. Elastomers are amorphous polymers that have the ability to stretch and then return to their original shape at temperatures above Tg. This property is important in applications such as gaskets and O-rings, so the development of synthetic elastomers that can function under harsh or demanding conditions remains a practical goal. At temperatures below Tg elastomers become rigid glassy solids and lose all elasticity. A tragic example of this caused the space shuttle Challenger disaster. The heat and chemical resistant O-rings used to seal sections of the solid booster rockets had an unfortunately high Tg near 0  °C. The unexpectedly low temperatures on the morning of the launch were below this Tg, allowing hot rocket gases to escape the seals. Copolymers The synthesis of macromolecules composed of more than one monomeric repeating unit has been explored as a means of controlling the properties of the resulting material. In this respect, it is useful to distinguish several ways in which different monomeric units might be incorporated in a polymeric molecule. The following examples refer to a two component system, in which one monomer is designated A and the other B. Statistical Copolymers Also called random copolymers. Here the monomeric units are distributed randomly, and sometimes unevenly, in the polymer chain: ~ABBAAABAABBBABAABA~. Alternating Copolymers Here the monomeric units are distributed in a regular alternating fashion, with nearly equimolar amounts of each in the chain: ~ABABABABABABABAB~. Block Copolymers Instead of a mixed distribution of monomeric units, a long sequence or block of one monomer is joined to a block of the second monomer: ~AAAAA-BBBBBBB~AAAAAAA~BBB~. Graft Copolymers As the name suggests, side chains of a given monomer are attached to the main chain of the second monomer: ~AAAAAAA(BBBBBBB~)AAAAAAA(BBBB~)AAA~. 1. Addition Copolymerization Most direct copolymerizations of equimolar mixtures of different monomers give statistical copolymers, or if one monomer is much more reactive a nearly homopolymer of that monomer. The copolymerization of styrene with methyl methacrylate, for example, proceeds differently depending on the mechanism. Radical polymerization gives a statistical copolymer. However, the product of cationic polymerization is largely polystyrene, and anionic polymerization favors formation of poly(methyl methacrylate). In cases where the relative reactivities are different, the copolymer composition can sometimes be controlled by continuous introduction of a biased mixture of monomers into the reaction. Formation of alternating copolymers is favored when the monomers have different polar substituents (e.g. one electron withdrawing and the other electron donating), and both have similar reactivities toward radicals. For example, styrene and acrylonitrile copolymerize in a largely alternating fashion. Some Useful Copolymers Monomer A Monomer B Copolymer Uses H2C=CHCl H2C=CCl2 Saran films fibers H2C=CHC6H5 H2C=C-CH=CH2 SBR styrene butadiene rubber tires H2C=CHCN H2C=C-CH=CH2 Nitrile Rubber adhesives hoses H2C=C(CH3)2 H2C=C-CH=CH2 Butyl Rubber inner tubes F2C=CF(CF3) H2C=CHF Viton gaskets A terpolymer of acrylonitrile, butadiene and styrene, called ABS rubber, is used for high-impact containers, pipes and gaskets. For polyisobutylene at a glance, click here! Polyisobutylene is a synthetic rubber, or elastomer. Its special because its the only rubber thats gas impermeable, that is, its the only rubber that can hold air for long periods of time. You may have noticed that balloons will go flat after a few days. This is because they are made of polyisoprene, which is not gas impermeable. Because polyisobutylene will hold air, it is used to make things like the inner liner of tires, and the inner liners of basketballs. Polyisobutylene, sometimes called butyl rubber, and other times PIB, is a vinyl polymer. Its very similar to polyethylene and polypropylene in structure, except that every other carbon is substituted with two methyl groups. It is made from the monomer isobutylene, by cationic vinyl polymerization. And this is that monomer isobutylene: Usually, a small amount of isoprene is added to the isobutylene. The polymerization is carried out at a right frosty -100 oC, or -148 oF for you Americans out there. This is because the reaction is so fast we cant control it unless we freeze it colder than a brass toilet seat in the Yukon. Polyisobutylene was first developed during the early 1940s. At that time, the most widely used rubber was natural rubber, polyisoprene. Polyisoprene was an excellent elastomer, and easy to isolate from the sap of the hevea tree. Huge plantations thrived in Malaysia and grew hevea trees to supply the worlds rubber needs. There was only one slight problem, and that was that Malaysia had just been conquered by the Imperial Japanese Army, and wouldnt you know we just so happened to be fighting the Second World War against them right at that moment. Before the war was over more than sixty million people would be dead. Deprived of natural rubber, the Allied nations did some quick thinking and came up with PIB. It obviously worked, because the Allies won the war. Ok, we didnt actually invent polyisobutylene during the war. It had been invented long before the war by chemists in Germany. Theres irony! But it wasnt very useful until American chemists came up with a way to crosslink it. What they did was to copolymerize isobutylene with a little bit, say, around one percent, isoprene. This is isoprene: When isoprene is polymerized with the isobutylene we get a polymer that looks like this: About one or two out of every hundred repeat units is an isoprene unit, shown in blue. These have double bonds, which means the polymer can be crosslinked byvulcanization just like natural rubber. What is this vulcanization? To find out, click here. Stealing Vulcans Fire There was a time long past when the only rubber we had was natural rubber latex, polyisoprene. Straight out of the tree, natural rubber latex isnt good for much. It gets runny and sticky when it gets warm, and it gets hard and brittle when its cold. Tires made out of it wouldnt be much good unless one lived in some happy land where the temperature was seventy degrees year round. A long time agohow long, you ask? It was about a hundred and sixty years ago, 1839 to be exact. This was before there were any cars to need tires, but the idea of a useable rubber was still attractive. One person trying to make rubber more useful was named Charles Goodyear, a tinkerer and inventor, and by no means a successful one at this point. While goofing around in his kitchen with a piece of fabric coated with a m