听力防护用品——耳塞.doc
听力防护用品——耳塞
一、听力防护分类
听力防护用品根据其结构形式的不同，大致可分为 3 大类： 1.能插入外耳道的耳塞； 2.能够将整个外耳廓罩住的耳罩； 3.有护耳罩的防噪声帽。
耳塞是指插入外耳道或置于外耳道口处的听力保护器。能较好地封闭外耳道，将外来的噪
声衰减，以达到保护听力的目的。耳塞的产品很多，从结构材料和形状上可分为 3 类：
1.软质塑料、橡胶耳塞，形状如瓶塞状，如圆锥形、伞形翼片耳塞；
2.弹性塑料耳塞，形状为圆柱体，如泡沫塑料耳塞；
3.纤维物耳塞，形状为球形。
二、耳塞的声衰减量
使用者戴耳塞与不戴耳塞两种情况下声阈之差的平均值叫声衰减量。表示耳塞衰减噪声的
能力，耳塞按照衰减性分为低、中、高频声耳塞和隔高频耳塞两类，分别用FZSE-1和 FZSE-2表示。耳塞的声衰减量见表 1 所示。
三、耳塞的结构
耳塞的结构是根据阻尼、反吸收等声学原理和佩戴舒适性的要求设计的，从使用效果看，
决定声衰减的主要原因有以下 4 个方面。
1．耳塞的气密性
耳塞的声衰减效果同耳塞与外耳道贴合的程度有关。塞体的光洁度、与耳道贴合的精密程
度和气密性好，则声衰减效果也相应提高。
2．耳塞的壁表厚度
噪声在为外表面反射和吸收效果与频率和耳塞壁表单位面积的厚度有关，如当噪声频率为
1000Hz，柱体耳塞壁厚为5mm 时，声衰减量大致是12dB；柱体耳塞壁厚为20mm 时，声衰减
量大致是22dB。
3．耳塞的外形
每个人外耳道的外形都不相同，为使耳塞与外耳道配合密切，提高密闭性，耳塞的外形应
具有多种形状，以适应不同的人员。
4．使用简便
设计耳塞的形状时应考虑到塞体便于从外耳道插入或取出，同时不易脱落，也不能插入外
耳道太深，以避免产生不适应的感觉。
四、耳塞的材料
制作耳塞的材料应具有质量轻、柔软、富有弹性等特点，而且对皮肤无毒副作用、无刺激，同时还应具有耐油、耐热、耐寒及抗老化性能。常用的耳塞材料有天然橡胶、塑料、聚氯乙烯纤维等。
专四听力原文
Legal Age for Marriage (1997) Throughout the United States, the legal age for marriage shows some difference./ The most com mon age without parents’ consent is 18 for both females and males./ However, persons who are under age in their home state can get married in another state, and then return to the home stat e legally married./ Each state issues its own marriage license./ Both residents and non-residents a re qualified for such a license./ The fees and ceremonies vary greatly from state to state./ Most st ates, for instance, have a blood test requirement, but a few do not./ Most states permit either a c ivil or religious ceremony, but a few require the ceremony to be religious./ In most states a waitin g period is required before the license is issued. /This period is from one to five days depending o n the state. / A three-day-wait is the most common. In some states there is no required waiting p eriod. The Railways in Britain (1998) The success of early railways, such as the lines between big cities,/ led to a great increase in railw ay building in Victorian times. / Between 1835 and 1865 about 25000 kilometers of track were bu ilt,/ and over 100 railway companies were created. / Railway travel transformed people's lives. / Trains were first designed to carry goods. / However, a law in the 19th century forced railway companies to run one cheap train a day / which stopped at every station and cost only a penny a mile. / Soon working class passengers found they could a fford to travel by rail. / Cheap day excursion trains became popular and seaside resorts grew rapi dly. / The railways also provided thousands of new jobs:/ building carriages, running the railways and repairing the tracks. / Railways even changed the time. / The need to run the railways on tim e meant that local time was abolished/ and clocks showed the same time all over the country. / United Nations Day (1999) The 24th of October is celebrated as United Nations Day. /it is a day that belongs to everyone./ A nd it is celebrated in most countries of the world./ Some countries celebrate for a week instead o f a day. /In many parts of the world, schools have special programs for the day. /Boys and girls in s ome communities decorate a UN tree./ In other communities, young people put on plays about t he UN./ Some libraries exhibit children’s art works from around the world. /Schools celebrate wit h the songs and dances of other countries/ or give parties where foods of other countries are ser ved./ No matter how the day is celebrated,/ the purpose of these celebrations is to help everyon e understand the UN,/ and the important roles it plays in world affairs. /The UN encourages peop le to learn about other lands and their customs./ In this way, people can gain a better understand ing and appreciation of peoples all over the world./ What We Know About Language (2000)
个人安全防护用品的使用规范
个人安全防护用品的使用须知 个人防护用品：是指劳动者在劳动中为防御物理、化学、生物等外界因素伤害人体而穿戴和配备的各种物品的总称。 1.按照用途分类 (1)以防止伤亡事故为目的的安全护品。主要包括： ａ防坠落用品，如安全带、安全网等； ｂ防冲击用品，如安全帽、防冲击护目镜等； ｃ防触电用品，如绝缘服、绝缘鞋、等电位工作服等； ｄ防机械外伤用品，如防刺、割、绞碾、磨损用的防护服、鞋、手套等； ｅ防酸碱用品，如耐酸碱手套、防护服和靴等； ｆ耐油用品，如耐油防护服、鞋和靴等； (2)以预防职业病为目的的劳动卫生护品。主要包括： ａ防尘用品，如防尘口罩、防尘服等； ｂ防毒用品，如防毒面具、防毒服等； ｃ防放射性用品，如防放射性服、铅玻璃眼镜等； ｄ防热辐射用品，如隔热防火服、防辐射隔热面罩、电焊手套、有机防护眼镜等； ｅ防噪声用品，如耳塞、耳罩、耳帽等。 2.以人体防护部位分类 （1）头部防护类：包括用各种材料制作的安全帽、一般防护帽、防尘帽、防水帽、防寒帽、防静电帽、防高温帽、防电磁辐射帽、防昆虫帽等。 （2）呼吸器官防护类：包括过滤式防毒面具，滤毒罐(盒)简易式防尘口罩(不包括纱布口罩)，复式防尘口罩，过滤式防微粒口罩，长管面具。 （3）眼、面部防护类：包括电焊面罩，焊接镜片及护目镜，炉窑面具，炉窑目镜，防冲击眼护具。
（4）听觉器官防护类：包括用各种材料制作的防噪声护具，主要有耳塞、耳罩和防噪声头盔。 （5）防护服装类：包括防静电工作服，防酸碱：工作服(除丝、毛面料外，材质必须经过特殊处理)，涉水工作服，防水工作服，阻燃防护服。 （6）手足防护类：包括绝缘、耐油、耐酸三种手套；绝缘、耐油、耐酸三种靴；盐滩靴，水产靴，用各种材料制作的低电压绝缘鞋，耐油鞋，防静电、导电鞋，安全鞋(靴)和各种劳动防护专用护肤用品。 （7）防坠落类防护用品：包括安全带(含速差式自控器与缓冲器)，安全网，安全绳。 安全帽的防护作用： 防止物体打击伤害；防止高处坠落伤害头部；防止机械性损伤；防止污染毛发伤害。它可以在以下几种情况下保护人的头部不受伤害或降低头部伤害的程度。 (1)飞来或坠落下来的物体击向头部时； (2)当作业人员从2m及以上的高处坠落下来时； (3)当头部有可能触电时； (4)在低矮的部位行走或作业，头部有可能碰撞到尖锐、坚硬的物体时。 安全帽的佩戴要符合标准，使用要符合规定。如果佩戴和使用不正确，就起不到充分的防护作用。一般应注意下列事项: 安全帽使用注意事项： (1)戴安全帽前应将帽后调整带按自己头型调整到适合的位置，然后将帽内弹性带系牢。缓冲衬垫的松紧由带子调节，人的头顶和帽体内顶部的空间垂直距离一般在25～50mm之间，至少不要小于32mm为好。这样才能保证当遭受到冲击时，帽体有足够的空间可供缓冲，平时也有利于头和帽体间的通风。 (2)不要把安全帽歪戴，也不要把帽沿戴在脑后方。否则，会降低安全帽对于冲击的防护作用。 (3)安全帽的下领带必须扣在颌下，并系牢，松紧要适度。这样不致于被大风
2011英语专四听力真题及答案
PART Ⅰ DICTATION 1. Listen to the following passage. Altogether the passage will be read to you four times. During the first reading, which will be done at normal speed, listen and try to understand the meaning. For the second and third readings, the passage will be read sentence by sentence, or phrase by phrase, with intervals of 15 seconds. The last reading will be done at normal speed again and during this time you should check your work. You will then be given 2 minutes to check through your work once more. Please write the whole passage on ANSWER SHEET ONE. In the late 1970s, air travel became affordable for the average family in the UK, and more people started travelling abroad for their summer holidays. After all, the British weather wasn’t ver y good, even in summer, so a lot of people left the country for a vacation. In the 1980s and 1990s, young people in the UK became wealthier on average. As a result, they started to go abroad in groups to places such as Spain and Greece. Once they arrived at their destination, they met with other groups of young people and had one long party. British holidaying habits have begun to change, however. Climate change means that the UK now has a hotter climate, so people do not need to go overseas to find good weather. Also, going abroad is more expensive. As a result, more British people are choosing to spend their summer holidays in the UK. PART Ⅱ LISTENING COMPREHENSION In Sections A, B and C you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. Mark the best answer to each question on Answer Sheet Two. SECTION A CONVERSATIONS In this section you will hear several conversations. Listen to the conversations carefully and then answer the questions that follow. Questions 1 to 3 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions. Now, listen to the conversation. 1. Which of the statements about the auto show is INCORRECT? A The show will have more stands this year. B The show will have more visitors this year. C The number of overseas visitors will be the same this year. D The number of exhibition days will be the same this year. 2. According to the conversation, the price for a stand would include A a catalogue B a poster C two desks D four chairs.
常戴耳机听音乐是否对听力有影响
常戴耳机听音乐是否对听力有影响 耳机对耳朵的伤害是有的，特别是开大的音量！！一般用mp3或mp4听音乐的话，最好不要超过机器里音乐的60%！连续听一个小时就要拔下耳塞休息一下，建议用入耳式耳塞，耳塞式分为入耳式的和非入耳式的，入耳式的可以隔绝外界噪音，在嘈杂的地方用入耳式耳塞听就不需要用太大的声音，从而可以保护听力。“当人们沉浸在MP4所带来的音乐享受中时，它本身潜在的危害也逐渐暴露出来，目前医院已接诊多例因长时间听音乐造成听力损伤的患者。”用耳机长时间听MP4，会对听觉神经末梢产生刺激，引起听觉神经异常兴奋，容易造成听觉疲劳；此外，当耳机接近鼓膜，能将声音信号提高9分贝左右，长久下去会对耳膜造成慢性伤害，严重时会导致永久性失聪。平时听MP4最好戴罩式耳机，这样能屏蔽掉较多的外界噪音，避免音量过大损伤听力；戴耳机听音乐时尽量把音量调低，听一段时间后应把耳机取下，轻轻揉一揉耳朵，放松一下，当耳朵发出“嗡嗡”声时表明听力神经已受伤，要尽快就医。听耳机的危害：长.时间听.易引起耳鸣.失眠.头痛.耳闷胀感以及渐进性听力减退因此要特别注意，不要长时间听。戴耳机听音乐别超过半小时耳机随着微型随身听、MP3、手机的出现离我们越来越近。但是，北京朝阳医院耳鼻咽喉头颈外科王宁宇主任提醒：经常戴耳机会对听觉系统造成影响，严重的甚至可以造成永久性
耳聋。有关医学资料表明，当人耳听到的音量超过85分贝时，时间较长可造成听觉疲劳；当音量高达110分贝以上时，足以使人体内耳的毛细胞死亡，严重者还会造成不可恢复性听力损伤。耳机的音量输出一般在84分贝左右，有些高频范围能达到120分贝。这样的音量对耳神经有很大的刺激作用，长时间会造成听力衰退，严重的会出现永久性耳聋和神经衰弱。王主任说，由于“首先出现的是高频听力下降，而我们日常交流所使用的语言频率并未受影响，所以早期常被忽视。”只有当听力损失向低频延伸，语言频率听力损失到一定程度后，才会出现主观感觉听力障碍，使语言交流和社交活动受到影响。因此，“使用耳机听东西给年轻人带来的影响，通常要多年之后才能够显现出来，所以，现在的人一般感觉不到其危害，而这也正是我们所担心的。”王主任说，人戴上耳机后，外耳几乎处于闭塞状态。高音量的音频声压直接进入耳内，集中传递到很薄的耳膜上。同时，耳塞机振动膜与耳膜之间距离很近，声波传播的范围小而集中，对耳膜听觉神经的刺激比较大。时间长了，易引起耳鸣、失眠、头痛、耳闷胀感以及渐进性听力减退。经常戴耳机还会造成一些全身性的不适，如头晕脑涨、恶心不适等。长此以往，容易出现注意力不集中、思维反应减慢、记忆力减退，甚至有烦躁不安、缺乏耐心等异常心理和情绪反应。因此，当你想戴耳机听音乐或英语时，最好：1.选用优质的耳机；2.尽量把声
常用安全工器具及个人安全防护用品清单
常用安全工器具及个人安全防护用品清单 集团企业公司编码：（LL3698-KKI1269-TM2483-LUI12689-ITT289-
常用安全工器具及个人安全防护用品清单一、绝缘安全工器具：绝缘操作棒、验电器、绝缘杆、绝缘测量杆、放电棒、绝缘梯、绝缘夹钳、核相器、绝缘绳、绝缘罩、绝缘隔板、绝缘垫、绝缘台、绝缘凳、橡胶绝缘导线软管、绝缘防护管、绝缘剪线钳等绝缘工具；以及带电作业防护服、绝缘服、绝缘网衣、绝缘肩套、绝缘手套、绝缘鞋(靴)、带电作业皮革保护手套、绝缘安全帽等绝缘防护用品。 二、一般安全工器具：安全措施标示牌、高处作业平台、检修防护架、高低凳、绝缘快装检修平台、升降板(登高板)、脚扣、升降梯、竹梯、软梯、飞车、下线爬梯、智能绝缘工具柜、安全工具柜、安全带试验拉力机、安全帽冲击试验机、测高仪、危险气体探测仪、SF6气体检漏仪、氧量测试仪、风速仪、噪音计、辐射剂量计、验电器信号发生器等其他安全用具。 三、安全围栏(网)：组合式护栏、绝缘隔离固定围栏、绝缘伸缩围栏、临时提示防护遮栏（小旗、带式）、围栏支架、地桩、安全警示带、安全围网等。 四、个人防护用品：
（一）绝缘防护用品：带电作业防护服、绝缘服、绝缘网衣、绝缘肩套、绝缘手套、绝缘鞋(靴)、带电作业皮革保护手套、绝缘安全帽等。 （二）坠落防护用品：包括安全带、速差自控器、缓冲器、安全自锁器、抓绳器、高空防坠落装置、安全防护网、安全绳等。 （三）头部（眼耳口鼻）防护用品：头部防护：各式安全帽；眼脸部防护：防护口罩、防电弧面罩、焊接面罩、防护眼镜、防护面屏；听力防护：各种防护耳塞；呼吸防护：各种防毒面具、空气呼吸器等； （四）身体（躯干）防护用品：防电弧服、专业防护服（包括：SF6、透气、避火隔热、防化等）、反光标志工作服等； （五）手部防护用品：专业防护手套（防滑、防割、防冻、防化、耐高温等）等。 （六）足部防护用品：安全鞋、专业防护鞋等。 1、工作鞋是指，在单位穿统一的鞋 2、劳保鞋是指特别的岗位所需要穿的鞋（如与水打交道岗位需要的雨鞋）
06年英语专四听力真题
TEST FOR ENGLISH MAJORS (2006) GRADE FOUR TIME LIMIT: 135 MIN PARTI DICTATION (15 MIN) Listen to the following passage. Altogether the passage will beread to you four times. During the first reading,which will be read at normal speed,listen and try to understand the meaning. For the second and third readings, the passage will be read sentence by sentence ,or phrase by phrase, with intervals of 15 seconds. The last reading will be read at normal speed again and during this time you should check your work. Y ou will then be given 2 minutes to check through your work once more. Please write the whole passage on ANSWER SHEET ONE. PART ⅡLISTENING COMPREHENSION (20 MIN) In Sections A ,B and C you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. Mark the correct answer to each question on your answer sheet. SECTION A CONVERSATIONS In this section you will hear several conversations. Listen to the conversations carefully and then answer the questions that follow. Questions I to 3 are based on the following conversation. At the end of the conversation ,you will be given 15 seconds to answer the questions. Now, listen to the conversation. 1. How did Mark get there? A. By train and by car. B. By plane and by coach. C. By train and by bus. D. By bus and by plane. 2. Mark used to wear all the following EXCEPT A. short hair. B. glasses. C. moustache. D. beard. 3. Where is the meeting for new students to be held? A. In the third room on the right. B. In the Common Room. C. In a room at the other end. D. In Room 501. Questions 4 to 6 are based on the following conversation. At the end of the conversation ,you will be given 15 seconds to answer the questions. Now,listen to the conversation. 4. What did Steve originally plan to do? A. To go to a park near the beach. ' B. To stay at home. C. To see a new film. D. To do some study. 5. Maggie finally decided to go to see a film because A. there was no park nearby. B. the weather wasn't ideal for a walk. C. it would be easier to go to a cinema. D. Steve hadn't seen the film yet. 6. Where did they plan to meet? A. Outside the Town Hall. B. Near the bank. C. In Steve's place. D. At the cinema.
(完整版)历年英语专四听力真题答案和原文.doc
2000 年专四听力答案 PART I DICTATION What We Know About Language Many things about language are a mystery and will remain so. / However, we now do know something about it. / First, we know that all human beings have a language of some sort. / No human race anywhere on earth is so backward / that it has no language of its own at all. /Second, there is no such thing as a primitive language. / There are many people whose cultures are undeveloped, / but the languages they speak are by no means primitive. / In all the languages existing in the world today,/ there are complexities that must have been developed for years. / Third, we know that all languages are perfectly adequate./ Each is a perfect means of expressing its culture. /And finally, we know that language changes over time, / which is natural and normal if a language is to survive. / The language which remains unchanged is nothing but dead. PART Ⅱ LISTENING COMPREHENSION SECTION A CONVERSATIONS Questions 1 to 3 are based on the following conversation. M:Jill,have you registered with the next semester? W:Not yet, there's still something that I'm not sure. Do you know if Professor Smith's economics 102 is still available to all undergraduate students? M:No, I don't think so. Last semester I tried to register in that course but all the other people told me not to. W:Why not? M:They said that my lack of knowledge in higher mathematics might be an obstacle in understanding Professor Smith's theory. W:Really? M:(I ) Jack tqld me that Professor Smith usually uses lots of formulas inside class. So you'd better make sure that you are extremely familiar with these formulas if you are seriously considering taking his course. W:What a shame I (2)My friends all told me that Professor Smith has lots of original ideas and he really can stimulate students to think. But I don't think I have the mathematical skills to keep up with the others. M:lf you want to take the course so much, why don't you register in a course in higher mathematics first? W. But I'm afraid that I will miss Professor Smith's course when I finish the mathematics course. M:Hey, I heard that Professor Smith would give the same course in the semester that starts next fall. ( 3 ) Why don't you take a year's higher mathematics and register in economics 102 the next fall? W:That sounds a good idea. I. [ B] 推断题。根据 ''They said that my lack of knowledge in higher mathematics might be an obstacle in understanding Professor Smith's theory. 可知，缺少高等数学知识会阻碍理解史密斯 教授的理论，所以学习经济学需要有高等数学知识，因而[ B]项伟正确答案。 2. [D] 细节题。文中提到 ''My friends all told me that Professor Smith has lots of original ideas and he really stimulate students to think. ”由此可知，史密斯教授有很很多新颖的观点，斌且
听力防护用品耳塞
听力防护用品——耳塞 一、听力防护分类 听力防护用品根据其结构形式的不同，大致可分为3大类：1.能插入外耳道的耳塞；2.能够将整个外耳廓罩住的耳罩；3.有护耳罩的防噪声帽。 耳塞是指插入外耳道或置于外耳道口处的听力保护器。能较好地封闭外耳道，将外来的噪声衰减，以达到保护听力的目的。耳塞的产品很多，从结构材料和形状上可分为3类： 1.软质塑料、橡胶耳塞，形状如瓶塞状，如圆锥形、伞形翼片耳塞； 2.弹性塑料耳塞，形状为圆柱体，如泡沫塑料耳塞； 3.纤维物耳塞，形状为球形。 二、耳塞的声衰减量 使用者戴耳塞与不戴耳塞两种情况下声阈之差的平均值叫声衰减量。表示耳塞衰减噪声的能力，耳塞按照衰减性分为低、中、高频声耳塞和隔高频耳塞两类，分别用FZSE-1和FZSE-2表示。耳塞的声衰减量见表1所示。 三、耳塞的结构
耳塞的结构是根据阻尼、反吸收等声学原理和佩戴舒适性的要求设计的，从使用效果看，决定声衰减的主要原因有以下4个方面。 1．耳塞的气密性 耳塞的声衰减效果同耳塞与外耳道贴合的程度有关。塞体的光洁度、与耳道贴合的精密程度和气密性好，则声衰减效果也相应提高。 2．耳塞的壁表厚度 噪声在为外表面反射和吸收效果与频率和耳塞壁表单位面积的厚度有关，如当噪声频率为1000Hz，柱体耳塞壁厚为5mm时，声衰减量大致是12dB；柱体耳塞壁厚为20mm时，声衰减量大致是22dB。 3．耳塞的外形 每个人外耳道的外形都不相同，为使耳塞与外耳道配合密切，提高密闭性，耳塞的外形应具有多种形状，以适应不同的人员。 4．使用简便 设计耳塞的形状时应考虑到塞体便于从外耳道插入或取出，同时不易脱落，也不能插入外耳道太深，以避免产生不适应的感觉。 四、耳塞的材料
英语专业四级考试真题听力部分历年听写原文(2005年-2014年)
英语专业四级考试真题听写原文2005年 The Wrist Watch It is generally believed that wrist watches are an exception / to the normal sequence in the evolution of man's jewelry. / Reversing the usual order, they were first worn by women, / and then adopted by men. / In the old days, queens included wrist watches among their crown jewelry. / Later, they were worn by Swiss workers and farmers. / Until World War I, Americans associated the watch with fortune hunters. / Then army officers discovered that the wrist watch was most practical for active combat. / Race car drivers also loved to wear wrist watches, / and pilots found them most useful while flying. / Soon men dared to wear wrist watches without feeling self-conscious. / By 1924, some 30 percent of man's watches were worn on the wrist. / Today, the figure is 90 percent. / And they are now worn by both men and women / for practical purposes rather than for decoration. 2006年 The internet The internet is the most significant progress in the field of communications.Imagine a book that never rend, a library with milion floors,or imagine a research project with thousands of sientists working around the clock forever.This is the magic of the internet.
听力防护用品——耳塞参考文本
听力防护用品——耳塞参 考文本 In The Actual Work Production Management, In Order To Ensure The Smooth Progress Of The Process, And Consider The Relationship Between Each Link, The Specific Requirements Of Each Link To Achieve Risk Control And Planning 某某管理中心 XX年XX月
听力防护用品——耳塞参考文本 使用指引：此安全管理资料应用在实际工作生产管理中为了保障过程顺利推进，同时考虑各个环节之间的关系，每个环节实现的具体要求而进行的风险控制与规划，并将危害降低到最小，文档经过下载可进行自定义修改，请根据实际需求进行调整与使用。 一、听力防护分类 听力防护用品根据其结构形式的不同，大致可分为3 大类：1.能插入外耳道的耳塞；2.能够将整个外耳廓罩住的 耳罩；3.有护耳罩的防噪声帽。 耳塞是指插入外耳道或置于外耳道口处的听力保护 器。能较好地封闭外耳道，将外来的噪声衰减，以达到保 护听力的目的。耳塞的产品很多，从结构材料和形状上可 分为3类： 1.软质塑料、橡胶耳塞，形状如瓶塞状，如圆锥形、伞 形翼片耳塞； 2.弹性塑料耳塞，形状为圆柱体，如泡沫塑料耳塞； 3.纤维物耳塞，形状为球形。
二、耳塞的声衰减量 使用者戴耳塞与不戴耳塞两种情况下声阈之差的平均值叫声衰减量。表示耳塞衰减噪声的能力，耳塞按照衰减性分为低、中、高频声耳塞和隔高频耳塞两类，分别用FZSE-1和FZSE-2表示。耳塞的声衰减量见表1所示。 三、耳塞的结构 耳塞的结构是根据阻尼、反吸收等声学原理和佩戴舒适性的要求设计的，从使用效果看，决定声衰减的主要原因有以下4个方面。 1．耳塞的气密性 耳塞的声衰减效果同耳塞与外耳道贴合的程度有关。塞体的光洁度、与耳道贴合的精密程度和气密性好，则声衰减效果也相应提高。 2．耳塞的壁表厚度 噪声在为外表面反射和吸收效果与频率和耳塞壁表单
个人防护用品穿脱教程
个人防护用品穿戴及脱卸顺序 【适用对象】所有进入养殖场内采样及记录人员、接触疑似或确诊病例的流调人员、发生动物疫情时的现场处置人员、生物安全二级实验室检测工作人员。 【防护用品配备】 一次性工作帽 医用防护口罩（N95及以上）
防护眼罩 一次性医用手套（两副） 一次性防水靴套
一次性防渗漏连体防护服 在特定情况下（如环境中有大量血液、其他体液、呕吐物或排泄物时），加穿防水围裙、防水靴。 【穿戴顺序】
步骤1：去除个人饰品及钥匙扣等物品 步骤2：戴一次性工作帽（覆盖头发和耳部）步骤3：戴一次性医用防护口罩（N95及以上） 步骤4：洗手和手消毒（六步洗手法）
步骤5：戴防护眼罩 步骤6：戴第一层一次性医用手套（佩戴前注意检查手套是否破损漏气） 步骤7：穿一次性防渗漏连体防护服（先穿下衣，再穿上衣，然后戴好帽子，最后拉上拉锁） 步骤8：穿一次性防水靴套 步骤9：戴第二层一次性医用手套（佩戴前注意检查手套是否破损漏气，第二层手套应压在防护服袖口上） 【脱摘顺序】 步骤1：脱去一次性防水靴套 步骤2：脱连体防护服（脱联体防护服时，先将拉链拉到底。向上提拉帽子，使帽子脱离头部，脱袖子；由上向下边脱边卷，污染面向里直至全部脱下放入医疗废物袋内）
步骤3：脱去外层一次性医用手套 步骤4：摘去防护眼罩 步骤5：脱一次性医用防护口罩（方法如下） 步骤6：脱一次性工作帽 步骤7：脱去内层一次性医用手套（用戴着手套的手捏住另外一只手套污染面的边缘将一只手套脱下，戴着手套的手握住脱下的手套，用脱下手套的手捏住另一只手套清洁面的边缘，将手套脱下） 步骤8：手部清洗消毒 【注意事项】 （1）用过的针头应立即丢入利器盒。 （2）操作过程中如发现防护用品破损，须及时更换。 （3）一次性个人防护物品使用后均要进行无害化处理。
2017专四答案+听力原文
2017专四答案+听力原文 Part Ⅰ DICTATION Learning Sympathy A big part of being human is feeling sympathy, / but how early on in our lives do we learn this? / Scientists find that babies respond to other people / by crying when other babies cry. / However, babies can’t distinguish between themselves and others / until they’re eighteen to twenty months old. / Toddlers start to show concern for others around this time. / Kids also begin to do things like comforting other people. / And by the time they’re three, / most children will try to protect a victim in a fight. Part Ⅱ LISTENING COMPREHENSION SECTION A TALK 1. a physical classroom 2. a coherent concept 3. personalized curriculum 4. (more) meaningful practice 5. feedback 6. collaborative learning 7. question and answer 8. fundamental human right 9. lifelong learning 10. innovation SECTION B CONVERSATIONS 1. What’s wrong with the man’s computer? 答案：A. It has wiped the data from the flash drive. 2. How will the man be compensated if the computer can’t be fixed? 答案：C. Get a new computer. 3. How did the man feel about the woman’s offer of compensation? 答案：D. Dissatisfied. 4. When will the service engineer come to fix the computer? 答案：B. After 8:30 tomorrow morning. 5. What is the man’s phone number? 答案：A. 6574-3205. 6. What sho uld we do if our neighbors didn’t reach out? 答案：B. Introduce ourselves first. 7. Which is the best way to handle a noisy neighbor? 答案：C. Give him a reason to stop. 8. What should we do if we have a nosy neighbor? 答案：D. Don’t answer their questions. 9. How long do we expect our neighbors to stay? 答案：B. Five to ten minutes. 10. Where can we get more information on this topic? 答案：D. CBS news website.