大學(xué)英語自學(xué)教程 unit 08

[00:00.00]Unit 8 Text A [00:02.25]第八單元 課文A [00:04.49]Telecommunication via Satellite [00:06.71]衛(wèi)星通信 [00:08.93]At the beginning of the twentieth century, [00:11.31]20世紀初 [00:13.69]there were four powerful means of transmitting and receiving information [00:17.37]有四種強有力的手段進行遠距離的信息傳送和接收， [00:21.05]over long distances: [00:23.24]它們是 [00:25.42]print,photography,telegraph and telephone. [00:28.85]印刷、照相、電報和電話。 [00:32.29]By the middle of the century, both radio and television [00:35.62]到20世紀中葉，無線電和電視 [00:38.95]had become established means of transmitting sounds and/or pictures. [00:42.63]都已成為公認的傳送聲音和/或圖象的手段。 [00:46.32]In 1964, the Olympic Games in Tokyo [00:49.89]1964年在東京舉行的奧運會 [00:53.47]became the first program to be transmitted via satellite. [00:56.86]是第一個通過衛(wèi)星傳送的節(jié)目。 [01:00.24]In order to transmit an event such as the Olympics via satellite, [01:04.26]為要通過衛(wèi)星傳送像奧運這樣的比賽項目， [01:08.28]television signals are first changed into radio waves, which are then [01:12.07]應(yīng)先把電視信號變成無線電波， [01:15.86]sent from a station on earth to an orbiting satellite. [01:18.94]然后從地球上的某個發(fā)射站把無線電波送上軌道衛(wèi)星。 [01:22.02]The satellite receives the radio waves and sends them back to earth, [01:26.15]衛(wèi)星收到無線電波，再把它們送回地球， [01:30.28]where another station picks them up [01:32.76]由地球上的另一個地面站接收信號， [01:35.24]and changes them back into television signals. [01:38.22]并把它產(chǎn)變回電視信號。 [01:41.20]Because any form of sound or visual information [01:44.28]因為任何形式的聲音或圖像信息 [01:47.36]can be changed into radio waves, [01:49.94]都能變成無線電波， [01:52.51]satellites axe capable of transmitting not only television broadcasts, [01:56.60]所以衛(wèi)星不僅能傳送電視廣播節(jié)目， [02:00.69]but telephone calls and printed materials such as books and magazines. [02:04.81]還可以傳送電話和像書籍、雜志這樣的印刷材料。 [02:08.94]The combination of satellites,which transmit information,computers, [02:12.66]傳送信息的衛(wèi)星存儲信息的計算機 [02:16.39]which store information,and television,which displays information, [02:19.81]和顯示信息的電視， 這三者結(jié)合起來 [02:23.23]will change every home into an education and entertain merit center. [02:26.61]能把每家庭變民教育和娛樂中心。 [02:30.00]In theory,every person will have access to an unlimited amount of information. [02:33.86]理論上說，每個人都能接觸無限多的信息。 [02:37.73]Another important use of telecommunication satellites was demonstrated in 1974 [02:42.86]1974年“太空老師”衛(wèi)星把教育節(jié)目 [02:47.99]when the "Teacher in Sky" [02:50.12]傳送給美國邊遠地區(qū)的課堂， [02:52.25]satellite transmitted educational programs to classes in remote areas of the United States. [02:56.43]顯示了通信衛(wèi)星的另一個重要用途。 [03:00.61]In 1975,many people in India saw [03:03.64]1975年，印度有很多人觀看 [03:06.67]television for the first time as watched programs about agriculture and health. [03:10.46]農(nóng)業(yè)節(jié)目和健康節(jié)目，這是他們第一次看電視。 [03:14.25]The satellite also demonstrated [03:16.62]衛(wèi)星還顯示了 [03:19.00]how it could provide help to people living in isolated areas where transportation is difficult. [03:23.27]它怎樣向與外界絕少來往的交通不便地區(qū)提供幫助。 [03:27.54]For example, [03:29.07]例如， [03:30.60]a health worker in an isolated area was able to transmit pictures of a patient's wound [03:34.78]某一這類地區(qū)的保健工作者可以把病人傷情的照片傳 [03:38.96] to a doctor far away. [03:40.88]送給遠處的醫(yī)生。 [03:42.80]He was then able to follow the doctor's instructions [03:45.78]之后，他就能夠根據(jù)醫(yī)生的指示 [03:48.75] on how to care for the patient. [03:50.88]照顧病人。 [03:53.01]The most common use of telecommunication satellites, [03:55.53]不過，通信衛(wèi)星的最通常的 [03:58.05]however,has been for transmitting telephone calls. [04:00.94]用途還是傳送電話。 [04:03.83]Most of them travel 40,000 miles to a satellite and then back to earth. [04:07.65]大部分電話要走40000英里才能到達衛(wèi)星然后返回地球。 [04:11.48]Ten years ago,a satellite was capable of receiving and transmitting [04:14.71]十年前，一個衛(wèi)星能夠同時接收和傳送 [04:17.93]more than 33,000 telephone conversations simultaneously. [04:21.36]33000多對通話。 [04:24.78]Now a single satellite is able to transmit over 100,000 conversations [04:29.35]現(xiàn)在只要一個衛(wèi)星就能傳送100000多對通話 [04:33.92]as well as several hundred television channels--all at the same time. [04:37.64]以及數(shù)百條電視頻道——這一切都是同時進行的。 [04:41.36]Telecommunication can make information [04:43.89]電信能使人迅速和便捷地 [04:46.41]from around the world available to use quickly and easily, [04:49.54]利用從世界和地來的信息， [04:52.68]but some people worry that this may be a risk to our privacy. [04:56.01]不過有些人擔(dān)心這會危及我們的隱私。 [04:59.34]If personal information is stored in computers, [05:02.21]如果計算機中存有私人的信息， [05:05.08]then it maybe easily transmitted via satellite [05:07.72]那么只要有人能付服務(wù)費， [05:10.36] to anyone who can pay for the service. [05:12.84]就可能通過衛(wèi)星所它傳送給這個人。 [05:15.32]Another worry is that telecommunication systems [05:18.35]人們的另一個擔(dān)心是電信系統(tǒng) [05:21.38]may isolate people from each other. [05:23.72]可能使用彼此不再來往。 [05:26.06]When people are able to shop from their homes, [05:28.74]當人們在家里就能購物， [05:31.42]do their banking without leaving the house, [05:33.74]不出門就能往銀行里存錢， [05:36.07]watch any movie they want on their television,as well as [05:38.90]在電視上就能看想看的電影， [05:41.73] get any information they need, [05:43.92]他們也能得到所需要的任何信息， [05:46.10]then there will not be as much contact between people. [05:49.34]那么人們之間的接觸就 不會那么多了。 [05:52.57]It is important to realize that the same technology that helps us may also harm us. [05:56.90]重要的是要能認識到，同一技術(shù)既能幫人，也能害人。 [06:01.22]We can prevent this from happening by carefully controlling the new technology. [06:05.00]我們應(yīng)該認真控制新技術(shù)，防止害人的事情發(fā)生。 [06:08.77]As one telecommunication expert says, [06:11.55]正如一位電信專家說的那樣， [06:14.33]"We must remember that technology alone is not the answer [06:17.67]“我們必須記住，技術(shù)本身不是解決的辦法。 [06:21.00]...It is the intelligent application of technology that will lead us to success." [06:25.02]、、、、、、明智地利用技術(shù)才會使我們成功?！? [06:29.04]Text B [06:30.48]課文B [06:31.92]What People Don't Know about Air. [06:33.89]關(guān)于空氣人們還需要了解些什么 [06:35.86]The air around us is important to everyone. [06:37.99]我們周圍的空氣對每個人都是至關(guān)重要的。 [06:40.12]Without air, we could not exist. [06:42.46]沒有空氣 我們就不能生存。 [06:44.79]Everyone understands that. [06:46.41]每個人都懂得這一點。 [06:48.03]But air is necessary in many other ways-- [06:50.16]但是空氣在許多其它方面也是人所必需的—— [06:52.29]ways that are not always so obvious or widely know. [06:54.82]這些方面并不是明顯和廣為人知。 [06:57.36]For example,if we did not have air,there would be no sound. [07:00.58]比如說，假如我們沒有空氣，就不會有聲音。 [07:03.81]Sound travels through air.Where there is no air,there is no sound. [07:07.35]聲音通過空氣傳播，沒有空氣的地方，也就沒有聲音。 [07:10.89]Without air,there would be no fire. [07:13.07]假如沒有空氣，就不會有火。 [07:15.25]There would be no cars or trucks,since motors need air in order to work. [07:18.64]因為發(fā)動機需要空氣才能工作，所以也不會有轎車或卡車。 [07:22.02]Without air there would be no wind or clouds. [07:24.45]沒有空氣不會有風(fēng)或云。 [07:26.88]There would be no weather,as we know it. [07:28.81]正如我們所知，也沒有天氣。 [07:30.74]The night time would be very cold and the days very hot. [07:33.47]夜間會很冷，白天會很熱。 [07:36.20]We would be forced to seek shelter from the sun, [07:38.33]我們將被迫尋找地主地方以遮蔽太陽, [07:40.46]as there would be no atmosphere to protect us from the sun's deadly rays. [07:43.49]因為沒有大氣保護我們不受致命的太陽光線的照射. [07:46.52]The atmosphere is all the air surrounding the earth. [07:48.79]大氣指的是包圍著地球的空氣. [07:51.07]Atmospheric pressure is the weight of all that air [07:53.70]大氣壓力乃是壓在地球表面 [07:56.34]against the surface of the earth. [07:58.26]的全部空氣的重量. [08:00.18]If we did not have atmospheric pressure, [08:02.26]假如我們沒有大氣壓力, [08:04.34]we could not have automobile tires. [08:06.26]我們便不可能有汽車輪胎. [08:08.18]The tires would burst if they did not have the pressure of the atmosphere [08:11.40]因為如果輪胎表面不受到大氣壓力， [08:14.63]against their surfaces. [08:16.21]輪胎就會爆裂。 [08:17.79]Large and powerful, [08:19.37]大氣廣大而有力， [08:20.95]the atmosphere consists of an ocean of gases hundreds of miles high. [08:24.07]它是由幾百英里厚的氣體的海洋構(gòu)成 的。 [08:27.19]It presses down on our bodies [08:29.02]壓在我們身上。 [08:30.85] with a force of more than fourteen pounds per square inch. [08:33.53]它以每平方英寸14磅以上的力量 [08:36.21]The narrow column of air [08:37.93]落在我們肩膀 的細空氣 [08:39.65]which rests upon our shoulders weighs almost 2,000 pounds. [08:42.63]柱子幾乎重達2000磅。 [08:45.61]But our bodies are built in such a way that this weight does not crush us. [08:48.80]但是我們的身體構(gòu)成 使得這個重量不會把我們壓壞。 [08:51.98]In this huge ocean of air [08:53.81]這個巨大的空氣海洋中 [08:55.64]there is more energy than in all the coal,oil,and gas we have on earth. [08:58.81]蘊藏的能量比我們地球上全部的煤、石油和煤氣中的能量都多。 [09:01.99]Electrical energy is collected in the atmosphere [09:04.67]大氣中可以收集電能， [09:07.34]as water is collected and stored in a dam. [09:09.63]正如同用堤壩懼和存儲水一樣。 [09:11.92]The existence of electricity in the air has been known for centuries. [09:14.95]人們知道空氣中有電能已經(jīng)好幾百年了。 [09:17.98]Men have gazed in wonder at the bright patterns of lightning in storm clouds. [09:21.20]他們曾經(jīng)驚異地注視著閃電在雨云密布的天空上展現(xiàn)耀亮的圖案。 [09:24.43]But a thorough study of electricity in the atmosphere [09:26.96]但在無線電和協(xié)達研制出之前， [09:29.50] was not possible until the development of radio and radar. [09:32.32]人們不可能對大氣中的電進行徹底的研究。 [09:35.14]One scientist,Dr.Sydney Chapman, [09:37.52]西德尼。查普曼博士是一位科學(xué)家 [09:39.89]has tried to explain the electric fieldwhich surrounds the earth. [09:42.57]他曾試解釋地球周圍的電場。 [09:45.25]He believes that the great storms on the sun [09:47.68]他相信強大的太陽風(fēng)暴 [09:50.11]create large amounts of electric energy. [09:52.68]能夠產(chǎn)生大量的電能。 [09:55.25]This energy is contained in a very light gas called hydrogen. [09:58.39]它含在一種叫氫氣的很輕的氣體中。 [10:01.52]The earth pulls the gas toward it, [10:03.35]地球把氫氣吸向它， [10:05.18]and a ring is formed around the earth [10:07.15]氫氣圍繞地球在它表面 [10:09.12]several thousand feet above its surface. [10:11.30]形成一個幾千英尺厚的環(huán)。 [10:13.49]The great space ring is a powerful current of electrical energy. [10:16.57]這個龐大的太空環(huán)是一股強大的電流。 [10:19.65]Sometimes the ring comes down and curves into the lower atmosphere, [10:22.77]有時這個環(huán)會下降，彎入在氣層的下層， [10:25.89]musing strange electrical effects. [10:27.97]從而產(chǎn)生很奇怪的電效應(yīng)。 [10:30.05]Dr. Chapman's ideas explain many things. [10:32.41]查普曼博士 的看法對很多現(xiàn)象作出 了解釋。 [10:34.78]It has long been known that there is an electric field inside the earth. [10:37.86]人們早就知道地球內(nèi)部存在電場。 [10:40.94]It moves in much the same manner [10:42.77]它的運動方式和大氣中 [10:44.60] as the electric energy contained in the atmosphere. [10:46.92]所含電能的運動方式一樣。 [10:49.25]Scientists now believe that the electric energy in the atmosphere [10:51.98]科學(xué)家們現(xiàn)在相信， [10:54.71]muses the electric energy inside the earth to flow. [10:57.38]大氣的電能引起了地球內(nèi)部電能的流動。 [11:00.06]If we can learn to control the energy in the atmosphere, [11:02.40]如果我們能夠?qū)W會控制大氣中的能量， [11:04.74]we will have an unending supply of energy. [11:07.17]我們的能源將是取之不盡，用之不竭的。 [11:09.60]Many scientists are trying to learn how to control it. [11:11.93]很多科學(xué)家正在努力了解怎樣控制它。 [11:14.27]In the meantime, even those of us who are not scientists [11:16.90]現(xiàn)在即使我們 這些濁科學(xué)家的人 [11:19.52]have begun to pay attention to air. [11:21.40]也開始注意空氣。 [11:23.29]We realize that air does not contain the same elements [11:25.70]我們認識到，現(xiàn)在空氣所含的元素 [11:28.12]that it contained years ago. [11:29.84]和多年前不一樣。 [11:31.57]Automobiles, airplanes, factories,and atomic explosions [11:35.25]汽車、飛機、工廠以及核工業(yè)爆炸 [11:38.93]have added dust and waste gases to the atmosphere. [11:41.36]往大氣中增添了很多塵埃和廢氣。 [11:43.79]It is time to learn how to protect our atmosphere, [11:46.08]現(xiàn)在該 是我們應(yīng)該學(xué)會怎樣保護我們的大氣 [11:48.36]the roof over the world of man. [11:50.33]人類世界的屋頂?shù)臅r候了。

00:00

00:00

MP3下載 文本下載