ABS,ABS+PC,PA,PC,PMMA,POM,PP,PE,PPO,PVC,TPE,TPO这些材料优缺点：

ABS塑料 特点：

1、综合性能较好,冲击强度较高,化学稳定性,电性能良好.

2、与372有机玻璃的熔接性良好,制成双色塑件,且可表面镀铬,喷漆处理.

3、有高抗冲、高耐热、阻燃、增强、透明等级别。

4、流动性比HIPS差一点，比PMMA、PC等好，柔韧性好。

ABS工程塑料具有优良的综合性能，有极好的冲击强度、尺寸稳定性好、电性能、耐磨性、抗化学药品性、染色性，成型加工和机械加工较好。ABS树脂耐水、无机盐、碱和酸类，不溶于大部分醇类和烃类溶剂，而容易溶于醛、酮、酯和某些氯代烃中。 ABS工程塑料的缺点：热变形温度较低，可燃，耐候性较差。用途：适于制作一般机械零件,减磨耐磨零件,传动零件和电讯零件. ABS+PC，俗称ABS加聚碳。是国内少数几种可能透用 的合料之一，不能自燃，外火燃烧时，表面有象聚碳燃烧一样的小颗粒析出， 黑色低于ABS，常见于电器件、 机械零配件等

聚酰胺(PA，俗称尼龙) PA是特性:坚韧、牢固、耐磨，无毒性. 缺点:不可长期与酸碱接触。常用于制作梳子、牙刷、衣钩、扇骨、网袋绳、水果外包装袋等。

PC是聚碳酸酯的简称，聚碳酸酯的英文是Polycarbonate，简称PC工程塑料，PC材料其实就是我们所说的工程塑料中的一种，作为被世界范围内广泛使用的材料， 聚碳酸酯无色透明，耐热，抗冲击，阻燃，在普通使用温度内都有良好的机械性能。同性能接近聚甲基丙烯酸甲酯相比，聚碳酸酯的耐冲击性能好，折射率高，加工性能好，聚碳酸酯的耐磨性差。一些用於易磨损用途的聚碳酸酯器件需要对表面进行特殊处理。日常常见的应用有光碟，眼睛片，水瓶，防弹玻璃，护目镜、银行防子弹之玻璃、车头灯等等、动物笼子宠物笼子。 聚碳酸酯还被用来制作登月太空人的头盔面罩。苹果公司的ipod音乐播放器和ibook笔记本电脑外壳也使用聚碳酸酯制作。

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ABS塑料

特点：

1、综合性能较好,冲击强度较高,化学稳定性,电性能良好.

2、与372有机玻璃的熔接性良好,制成双色塑件,且可表面镀铬,喷漆处理.

3、有高抗冲、高耐热、阻燃、增强、透明等级别。

4、流动性比HIPS差一点，比PMMA、PC等好，柔韧性好。

ABS工程塑料具有优良的综合性能，有极好的冲击强度、尺寸稳定性好、电性能、耐磨性、抗化学药品性、染色性，成型加工和机械加工较好。ABS树脂耐水、无机盐、碱和酸类，不溶于大部分醇类和烃类溶剂，而容易溶于醛、酮、酯和某些氯代烃中。

ABS工程塑料的缺点：热变形温度较低，可燃，耐候性较差。

用途：适于制作一般机械零件,减磨耐磨零件,传动零件和电讯零件.

ABS+PC，

俗称ABS加聚碳。是国内少数几种可能透用 的合料之一，不能自燃，外火燃烧时，表面有象聚碳燃烧一样的小颗粒析出， 黑色低于ABS，常见于电器件、 机械零配件等

聚酰胺(PA，俗称尼龙)

PA是特性:坚韧、牢固、耐磨，无毒性.

缺点:不可长期与酸碱接触。

常用于制作梳子、牙刷、衣钩、扇骨、网袋绳、水果外包装袋等。

PC是聚碳酸酯的简称，聚碳酸酯的英文是Polycarbonate，简称PC工程塑料，PC材料其实就是我们所说的工程塑料中的一种，作为被世界范围内广泛使用的材料，

聚碳酸酯无色透明，耐热，抗冲击，阻燃，在普通使用温度内都有良好的机械性能。同性能接近聚甲基丙烯酸甲酯相比，聚碳酸酯的耐冲击性能好，折射率高，加工性能好，

聚碳酸酯的耐磨性差。一些用於易磨损用途的聚碳酸酯器件需要对表面进行特殊处理。

日常常见的应用有光碟，眼睛片，水瓶，防弹玻璃，护目镜、银行防子弹之玻璃、车头灯等等、动物笼子宠物笼子。

聚碳酸酯还被用来制作登月太空人的头盔面罩。苹果公司的ipod音乐播放器和ibook笔记本电脑外壳也使用聚碳酸酯制作。

PMMA

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Hamlet

10英教（1） 1028010002 朱莉 Hamlet is a classical representative work of a great English playwright and poet-William Shakespeare. William Shakespeare is often called England's national poet and the "Bard of Avon". His four great comedies are Twelfth Night、Midsummer Night's Dream 、The Merchant of Venice and As You Like It. His four representative tragedies are Hamlet、 Othello、 King Lear and Macbeth. While Hamlet is most popular and the best work in the four representative tragedies, because it is a philosophical exploration of life and death.

The hero of Hamlet is Prince Hamlet of Denmark, son of deceased King Hamlet.When he back the home in a hurry from Germany for his father's funeral ,he only to find his father death mysteriously and his mother remarriage with Claudius- his father’s brother hastily. He is doubt that his uncle killed his mother to rob his beautiful mother and his father throne. Suddenly a Ghost appears to lead Hamlet to a secluded place, claims that it is the actual spirit of his father. It tells hamlet a secret. His father was murdered by his brother Claudius pouring poison in his ear. In order to revenge on his uncle for killing his father, he pretend to be mad and suffered a series of misery. To this, he started the difficult revenge course, launched the life and death contest with Claudius. Finally, sent out sword the revenge to Claudius. Hamlet is a absolute tragedy,

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Personal Statement For Marshall Scholar

application 个人陈述

If concerned parents ever try to argue that video games rot your brain, I think I will be their nemesis. From the age of seven, I was a video game junkie, rushing home from school to defeat the forces threatening virtual worlds. At recess, my friends and I would pretend to be our favorite video game characters, imagining our own stories and saving the world at least once a day. By the age of twelve my thumb muscles had become overdeveloped, hampering my ability to grip a pencil. I would argue, however, that this was the only unhealthy effect that playing video games had caused me. I maintained a large group of friends, developed a great imagination, and spent just as much time playing outside as I did in front of the screen.

Initially, I think the dramatic storylines and characters of video games appealed to me more than what I saw as a lackluster social reality. Like many in my generation, I grew up believing that wanting to change the world was immature and naive. At the same time, I felt deeply devoted to a set of ideals originally influenced by my Catholic upbringing. Though I had slowly grown frustrated with the hypocrisy I saw in the church, my faith had remained. As a result, I felt a need to search for a way to truly change the world for the better - to help in some

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Abraham Lincoln

Of the People, By the People, For the People: The Gettysburg Address

November 19, 1863;

Gettysburg

亚伯拉罕 林肯

民有民治民享

——葛底斯堡演讲

1863年11月19日

葛底斯堡

Four score and seven years ago our fathers brought forth on this continent a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.

Now we are engaged in a great civil war, testing whether that nation or any nation so conceived and so dedicated, can long endure. We are met on a great battlefield of that war. We have come to dedicate a portion of the field as a final resting place for those who have gave their lives that that nation might live. It is altogether fitting and proper that we should do this.

But in a larger sense, we cannot dedicate, we cannot consecrate, we cannot hallow this ground. The brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember what we say here, but it can never forget what they did here. It is for us, the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us – that from these honored dead we take increased

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Abraham Lincoln

Of the People, By the People, For the People: The Gettysburg Address

November 19, 1863;

Gettysburg

亚伯拉罕 林肯

民有民治民享

——葛底斯堡演讲

1863年11月19日

葛底斯堡

Four score and seven years ago our fathers brought forth on this continent a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.

Now we are engaged in a great civil war, testing whether that nation or any nation so conceived and so dedicated, can long endure. We are met on a great battlefield of that war. We have come to dedicate a portion of the field as a final resting place for those who have gave their lives that that nation might live. It is altogether fitting and proper that we should do this.

But in a larger sense, we cannot dedicate, we cannot consecrate, we cannot hallow this ground. The brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember what we say here, but it can never forget what they did here. It is for us, the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us – that from these honored dead we take increased

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? Online retail sales as a percentage of total retail sales

? Total value of online retail sales for year 2: 56

? What was the value of total retail sales for Q4 of year 2: 460.79

? The steepest proportion increase was between Q3 and Q4 of year2: False ? The only quarter fell compared to previous was Q1 of year2: True

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