Polyethylene Terephthalate Plastics

Polyethylene Terephthalate Plastics PET plastics or polyethylene terephthalate is used in many different products. The properties of PET makes it ideal for a number of different uses and these advantages make it one of the most common plastics available today. Understanding more about the history of PET, as well as the chemical properties, will allow you to appreciate this plastic even more. In addition, most communities recycle this type of plastic, which allows it to be used again and again. What are the chemical properties of PET? PET Chemical Properties This plastic is a thermoplastic resin of the polyester family and is commonly used in many different products, including synthetic fibers. It can exist in both a transparent and a semi-crystalline polymer, depending upon the processing and thermal history. Polyethylene terephthalate is a polymer that is formed by combining two monomers: modified ethylene glycol and purified terephthalic acid. PET can be modified with additional polymers as well, making it acceptable and usable for other uses. History of PET The history of PET began in 1941. The first patent was filed by John Whinfield and James Dickson, along with their employer, the Calico Printers Association of Manchester. They based their invention on the earlier work of Wallace Carothers. They, working with others, created the first polyester fiber called Terylene in 1941, which was followed by many other types and brands of polyester fibers. Another patent was filed in 1973 by Nathaniel Wyeth for PET bottles, which he used for medicines. Advantages of PET PET offers several different advantages. PET can be found in many different forms, from semi-rigid to rigid. This is largely dependent upon its thickness. It is a lightweight plastic that can be made into a number of different products. It is very strong and has impact resistant properties as well. As far as color, it is largely colorless and transparent, although color can be added, depending upon the product that it is being used for. These advantages make PET one of the most common types of plastic that is found today. Uses of PET There are many different uses for PET. One of the most common is for drink bottles, including soft drinks and more. PET film or what is called Mylar is used for balloons, flexible food packaging, space blankets, and as a carrier for magnetic tape or backing for pressure sensitive adhesive tape. In addition, it can be formed to make trays for frozen dinners and for other packaging trays and blisters. If glass particles or fibers are added to the PET, it becomes more durable and stiffer in nature. PET is largely used for synthetic fibers, also known as polyester. PET Recycling PET is commonly recycled in most areas of the country, even with curbside recycling, which is simple and easy for everyone. Recycled PET can be used in a number of different things, including polyester fibers for carpeting, parts for cars, fiberfill for coats and sleeping bags, shoes, luggage, t-shirts, and more. The way to tell if you are dealing with PET plastic is looking for the recycling symbol with the number 1 inside of it. If you are not sure that your community recycles it, simply contact your recycling center and ask. They will be happy to help. PET is a very common type of plastic and understanding its composition, as well as its advantages and uses, will allow you to appreciate it a little bit more. You most likely have lots of products in your home that contains PET, which means that you have the opportunity to recycle and allow your product to make even more products. Chances are you will touch different PET products over a dozen times today.

The Scientific Basis for Defining Seasons

The Scientific Basis for Defining Seasons Contrary to common belief, modern meteorology recognized that the beginning of any season is the day on which the sun passes over particular latitude rather than how cold or warm the following will be. Hashtag: #FirstDayOfFall Ancient and Modern Meteorology Meteorological phenomena such as storms, lightning, and thunder are often considered dangerous and frightening for many people. The ability to predict their occurrence in the past was valued in many cultures. In fact, there is a large body of literature that spans the ancient period dedicated to the prediction and explanation of meteorological and astronomical events including animal behavior.   The division of the year into seasons enables the ancient culture to select the proper time plowing, sowing, reaping, and harvesting, making voyages with ships, prepare and protect themselves for against the natural severity of the seasons. CAN SCIENCE GO TOO FAR? However, ancient meteorology was largely based on past experience or preservation of the events of past weather and their sequence, speculations on the relation between events and proximate causes, philosophy, appeal to the deities, and belief in personal weather-control and magic.   The practice was only changed in the mid 19th century when a collection of facts has been operated by electric–telegraph and now radiotelegraphy.   Although recording observation and discussing them from a philosophical point of view still remains to this day, meteorologist today have a multitude of facts and records to base their forecast and in creating a weather map. Weather and Seasons Weather maps are important tools for developing and explaining weather forecasts. They vary in scope as there are national, continental, and global weather maps. Surface weather maps commonly contain identified fronts; high and low-pressure areas and temperatures, wind strength and air pressure and often used to provide information on the present weather condition.   Forecast weather maps, as the name suggests, are computer generated maps to predict changes in the weather.   Meteorologist also developed short-term (18-36 hours) and long-term (5 days) maps that are updated daily. However, since weather condition is rapidly changing, the weather forecast may not always be accurate and mere honest guesses of the weather condition for a certain period of time. The above surface map illustrates four different fronts – cold, warm, stationary, and occluded.   Note that these fronts separate different air masses and associated with lower pressure. A meteorologist using this map will likely forecast that weather along the stationary front (points A and B) will be clear to partly cloudy. The weather condition in the cold front (points B to C) will be cold, rainy in green-shaded areas, and snowy in the white shaded areas. Contrary to common belief, modern meteorology recognized that the beginning of any season is the day on which the sun passes over particular latitude rather than how cold or warm the following will be.   For instance, the first day of summer in the Northern Hemisphere is June 21 or when the sun is at its highest position in the noonday sky or 23  ½ degrees north (N) latitude. Each day past June 21, the noon sun is slightly lower in the sky as 12 hours or more of daylight in the Northern Hemisphere begins to shorten. COMPUTER SCIENCE DIPLOMA THESIS By September 22, the sun is directly above the equator and the astronomical beginning of fall officially begins in the Northern Hemisphere.   Three months after the autumnal equinox, the sun on December 21, is further away from the tilted Northern Hemisphere where days are shorter and nights are longer.   On this day, the sun shines directly above latitude 23  ½ degrees S (Tropic of Capricorn) or the first day of winter in the Northern Hemisphere. The first day of spring occurs around March 20 or when the sun crosses the equator and moving northward.

TuneCore Essay Example | Topics and Well Written Essays - 1500 words

TuneCore - Essay Example This means that tune core do not charge a portion of the sales which can be expressed as a percentage. The artists then keep for themselves all earnings they get from all the online stores. TuneCore also offer publishing services to make sure that artists get compensations properly when any of their music is used on the web. This publishing administration is however, available for $75 fee which is paid once. Then the artists are able to access the Content ID on YouTube and many artists through these services have succeeded a lot especially in the YouTube marketplace to market and sell their videos (TuneCore Blog 2013). These artists working with TuneCore are able to earn a lot of royalties from their music downloads and music streams. This has led to expansion of TuneCore revenue base and general marketing and music distribution. Schwartz (2013) says that tapping into INDmusic was a great advantage to TuneCore in expanding its business and increasing the number of their retail customers; that is the number of artists. The company was then able to collect revenue from advertisements on YouTube on behalf of their artists. TuneCore was able to help their artists put their music in other forms like movies and in shows in various televisions. Following this, there was a remarkable increase in royalties from publishing. Currently, the network of INDmusic covers a number of artists not less than 270. These artists then get the opportunity to utilize the reach of INDmusic and be able to pick up their personal visibility. With high demand generated by TuneCore’s services, their artists are able to collect royalties from several digital downloads and streams. What the artists have to do is write their songs and do a recording of them which later upload in audio form. This audio form of the song is then send to the various digital stores of music where fans of the artists can access and buy the song.

STAT Statistics Project Example | Topics and Well Written Essays - 1250 words

STAT - Statistics Project Example From these results we reject the null hypothesis that the average hotel price in Philadelphia is $129.50 since we have proven that the average hotel room at Philadelphia is significantly different from $125 hence its not $ 129.50. Sample size = 250 and they believed that the average is 75%. It means that the confidence interval is at ÃŽ ± = 0.25. We calculate the sample mean as xbar= 250/168 = 1.488 and that the claimed average =0.75 thus t = 1.48-0.75)/ Since the resultant Z statistic test is less than the obtained value of (168/250) = 0.672, we reject the null hypothesis that there proportion of drivers under influence of alcohol are significantly less than 75%. We conclude that the proportion of drivers under the influence of alcohol is not less than 75%. Z = {Sample mean- ÃŽ ¼0}/ ÃŽ ´/√n = {9-6} Ã · 2.47/√100 = 12.146. The critical value of Z is obtained from the tables as Z ÃŽ ± /2 = Z 0.05 /2 = Z 0.025 = 1.96. but since the assumed is greater than the test statistic, we reject the null hypothesis that the mean waiting time will be 6 minutes or that its not true that the average waiting time will be reduced from the current 9- 10 minute. Let us find out the critical value of chi-squared (χ2) = (n-1) s2 Ã · ÃŽ ´2 = (25-1)0.4 /0.3 = 32. This is the obtained chi-square and from the chi-square tables, we deduce the value of the critical region as 36.42 (Bowman par 3). Since it’s a left- tailed test, our rejection region is less than 36.42 i.e. (χ2

Comparing the Rich versus the Poor Essay -- Poverty

Rich v. Poor Take a moment and picture a child half naked in the streets. His body has been harshly neglected. Little to no calf muscles exist. His ribs are plainly countable. One, two, three up his left side. You can do the same to his right. Malnutrition only vaguely begins to describe his condition. The worst of anorexia doesn’t even compare to this child’s inhumane state. As for shelter, he lives in a dilapidated hut. Food is a luxury, as the child may be fed only three or four times a week. He’s expected to die by the age of five due to severe malnutrition and disease. This is the grim portrait of an Ethiopian child in absolute poverty. His life doesn’t allow for the basic essentials of food, shelter, or clothing. In today’s world poverty is not only viewed in terms of average income/wealth, but as the lower end of distribution regarding income, education, health accessibility, nutrition, productivity, participation in politics, etc. Thus, poverty is defined as the â€Å"economic condition in which people lack sufficient income to obtain certain minimal levels of health services, food, housing, clothing, and education generally recognized as necessary to ensure an adequate standard of living† (Funk & Wagnall 1). Adequate, however, depends on the standard of living for each country. There are two different types of poverty today—relative and absolute. Nearly half of a billion people live in relative poverty—â€Å"meaning that some citizens are poor, relative to the wealth enjoyed by their neighbors† (Singer 218). To put these figures in terms one can relate to, it’s estimated that about 10% of human life resides in relative poverty. This is a substantial amount, but their condition is quite well ... ...ay, â€Å"prevent something very bad from happening, without [thereby] sacrificing anything of comparable moral significance†¦Ã¢â‚¬  (Singer 229), and we should. Works Cited * Hardin, Garret. â€Å"Living on a Lifeboat.† Contemporary Moral Problems. American Institute of Biological Sciences, 1974: 246-257. * â€Å"Poverty.† Funk & Wagnall’s New Encyclopedia. 1992: 1-2. * Quadrini, Vincenzo.; Rà ­os-Rull, Josà ©-Và ­ctor. â€Å"Understanding the U.S. Distribution of Wealth.† http://newfirstsearch.oclc.org * Federal Reserve Bank of Minneapolis Quarterly Review v. 21 no2. Spring. 1997: 22-36. * Singer, Peter. â€Å"Rich and Poor.† Practical Ethics. 2nd ed. Cambridge: Cambridge University Press, 1993: 218-246. * Speth, James Gustave. â€Å"The Plight of the Poor: The Unites States Must Increase Development Aid.† Foreign Affairs v. 78 no3. May/June. 1999: 1-3.

Athena and Telemachus

Chayenne Georges Prof Jette Eng-111 3/10/13 Athena and Telemachus Athena, the Grey eyed goddess, is one of those women in The Odyssey whose role is so important. She is the goddess of wisdom, who helps Telemachus on a journey to bring his father back home. Athena goes to Odysseus son to put courage in him. She doesn’t show her true self to humans; instead Athena disguises herself on three different occasions. She appeared as Odysseus friend Mentes, when she approached Telemachus. When Athena touches down Ithaca she is immediately spotted by Telemachus, who was sitting unhappy among the suitor.Free-will is greatly used between Athena and Telemachus, when she is persuading him to find his father. Athena says, â€Å"If I were you, I should take these steps to make these men disperse,† [Homer, 320]. Here Athena is trying to get Telemachus to realize that it’s time for his father to come to Ithaca, and he has to get the suitors out of his home. In The Odyssey Telemach us is portrayed as a boy who has to grow up, he needs to find the courage and guidance to find his father, Athena is Telemachus’ voice she is the one who helps give this courage to him.The Odyssey give you more of an external view of the characters, it doesn’t really expose their inner thoughts or feelings. Meadowlands by, Louise Gluck demonstrates Telemachus’ true feelings for his father. â€Å"When I was younger I felt sorry for myself compulsively; in practical terms, I had no father; my mother lived at her loom hypothesizing her husband’s erotic life;† [Meadowlands, Telemachus’ Kindness, 24]. Here a whole different side of Telemachus is being identified.In Meadowlands Telemachus is angry at his parents, he pity them. This quote from Telemachus’ Kindness shows the anger he has towards his father for leaving. He feels as if he had no childhood because he never had a father figure in his life. Penelope sorrowed over Odysseus absence, instead of marrying one of the suitors and give Telemachus a father figure, someone to look to, Penelope often fantasied about her husband life and what he is doing while he is gone. She would loom every night to stall the suitors, keep from marrying them.

Determine Concentration and Molarity

Molarity is one of the most common and important units of concentration used in chemistry. This concentration problem illustrates how to find the molarity of a solution if you know how much solute and solvent are present. Concentration and Molarity Example Problem Determine the molarity of a solution made by dissolving 20.0 g of NaOH in sufficient water to yield a 482 cm3 solution. How to Solve the Problem Molarity is an expression of the moles of solute (NaOH) per liter of solution (water). To work this problem, you need to be able to calculate the number of moles of sodium hydroxide (NaOH) and be able to convert cubic centimeters of a solution into liters. You can refer to the Worked Unit Conversions if you need more help. Step 1 Calculate the number of moles of NaOH that are in 20.0 grams. Look up the atomic masses for the elements in NaOH from the Periodic Table. The atomic masses are found to be: Na is 23.0H is 1.0O is 16.0 Plugging these values: 1 mol NaOH weighs 23.0 g 16.0 g 1.0 g 40.0 g So the number of moles in 20.0 g is: moles NaOH 20.0 g Ãâ€" 1 mol/40.0 g 0.500 mol Step 2 Determine the volume of solution in liters. 1 liter is 1000 cm3, so the volume of solution is: liters solution 482 cm3 Ãâ€" 1 liter/1000 cm3 0.482 liter Step 3 Determine the molarity of the solution. Simply divide the number of moles by the volume of solution to get the molarity: molarity 0.500 mol / 0.482 litermolarity 1.04 mol/liter 1.04 M Answer The molarity of a solution made by dissolving 20.0 g of NaOH to make a 482 cm3 solution is 1.04 M Tips for Solving Concentration Problems In this example, the solute (sodium hydroxide) and solvent (water) were identified. You may not always be told which chemical is the solute and which is the solvent. Often the solute is a solid, while the solvent is a liquid. Its also possible to make up solutions of gases and solids or of liquid solutes in liquid solvents.  In general, the solute is the chemical (or chemicals) present in smaller amounts. The solvent makes up most of the solution.  Molarity is concerned with the total volume of the solution, not the volume of the solvent. You can approximate molarity by dividing moles of solute by volume of solvent that is added, but this isnt correct and can lead to significant error when a large amount of solute is present.Significant figures can also come into play when reporting concentration in molarity. There will be a degree of uncertainty in the mass measurement of the solute. An analytical balance will yield a more precise measurement than weighing on a kitchen scale, fo r example. The glassware used to measure the volume of solvent also matters. A volumetric flask or graduated cylinder will yield a more precise value than a beaker, for example. Theres also an error in reading the volume, relating to the meniscus of the liquid. The number of significant digits in your molarity is only as many as that in your least precise measurement.