【正文】 四、太陽(yáng)能中央熱水系統(tǒng)的社會(huì)效益在地球環(huán)境日益污染惡化、地球資源日益匱乏的今天，世界各國(guó)有識(shí)之士都在積極尋找、開(kāi)發(fā)一種無(wú)污染的新能源，太陽(yáng)能無(wú)污染，并且取之不盡用之不絕，所以開(kāi)發(fā)、推廣太陽(yáng)能產(chǎn)品具有良好的社會(huì)效益和長(zhǎng)遠(yuǎn)的社會(huì)意義。在沒(méi)有太陽(yáng)陽(yáng)光或者太陽(yáng)陽(yáng)光不足時(shí)怎么辦？太陽(yáng)能熱水系統(tǒng)一般配備輔助加熱設(shè)備解決這一問(wèn)題，下文將作簡(jiǎn)單介紹。 真空管太陽(yáng)能熱水器技術(shù)參數(shù)長(zhǎng)度L=1500mm直徑φ=47mm空曬溫度≥200℃真空管單管得熱量70－80瓦/小時(shí)真空度≤102帕承壓熱損系數(shù)≤℃抗沖擊φ25mm冰雹產(chǎn)水量晴天產(chǎn)水溫度4090℃五星太陽(yáng)能公司每組集體型真空管太陽(yáng)能熱水器技術(shù)參數(shù)規(guī) 格50支/組水容量77㎏凈重量105㎏運(yùn)行總重量182㎏采光面積5㎡每天產(chǎn)熱水量≥375㎏凈占地面積㎡安裝占地面積㎡樓面負(fù)載≤50㎏/㎡長(zhǎng) 度寬 度高 度二、太陽(yáng)能中央熱水系統(tǒng)的防凍 北京地區(qū)太陽(yáng)能資源豐富，全年日照時(shí)間長(zhǎng)，特別是冬季陽(yáng)光好但是氣溫低，若冬季使用須考慮防凍措施。Firemen had been fighting the forest fire for nearly three weeks before they could get it under control. A short time before, great trees had covered the countryside for miles around. Now, smoke still rose up from the warm一、太陽(yáng)能熱水器技術(shù)參數(shù)我國(guó)地域遼闊，太陽(yáng)能資源豐富，是太陽(yáng)熱水器大顯身手的舞臺(tái)，但因各地太陽(yáng)能資源與環(huán)境溫度等氣象條件以及各地水質(zhì)的不同，使用適宜當(dāng)?shù)氐奶?yáng)熱水器系統(tǒng)是非常重要的。Lesson60 The future 卜算未來(lái) has been invented and it has been used to detect gold which has been buried in the ground. The machine was used in a cave near the seashore whereit is saidpirates used to hide gold. The pirates would often bury gold in the cave and then fail to collect it. Armed with the new machine, a search party went he did not like it. She enjoyed herself making the assistant bring almost everything in the window before finally buying the dress she had first asked for.You don39。Lesson51 Reward for virtue 對(duì)美德的獎(jiǎng)賞ll get off here.39。Oh dear,39。39。 but I don39。Dentists always ask questions when it is impossible for you to answer. My dentist had just pulled out one of my teeth and had told me to rest for a while. I tried to say something, but my mouth was full of cottonwool. He knew I collected birds39。230 !s money was paid back in this way. The last note said:39。再闡述選擇太陽(yáng)能熱水系統(tǒng)的幾個(gè)要素希望能夠讓各位了解如何選擇太陽(yáng)能熱水系統(tǒng)，最后簡(jiǎn)介我們公司、公司系列產(chǎn)品并附部分客戶名錄及客戶的評(píng)價(jià)，希望能夠讓各位初步了解我們公司是你們單位值得長(zhǎng)期合作的伙伴，并進(jìn)一步參觀考察我們公司。Lesson61 Trouble with the Hubble 哈勃望遠(yuǎn)鏡的困境A relation of yours is ing to see you. She will be arriving this evening and intends to stay for a few days. The moment you leave this tent, you will get a big surprise. A woman you know well will rush towards you. She will speak to you and then she will lead you away from this place. That is all.39。Lesson59 In or out ？ 進(jìn)來(lái)還是出去？After breakfast, I sent the children to school and then I went to market. It was still early when I returned home. The children were at school, my husband was at work and the house was quiet. So I decided to make some tarts for tea. In a short time I was busy mixing butter and flour and my hands were soon covered with sticky pastry. At exactly that moment, the telephone rang. Nothing could have been more annoying. I picked up the receiver between two sticky fingers and was dismayed when I recognized the voice of Mrs Bates. It took me ten minutes to persuade her to ring back later. At last I hung up the receiver. What a mess! There was pastry on my fingers, on the telephone, and on the doorknobs. I had no sooner got back to the kitchen than the doorbell rang loud enough to wake the dead. This time it was the postman and he wanted me to sign for a registered letter ! We are going back now,39。 I forgot to put you off.39。ll have to get off here,39。 39。I love travelling in the country, but I don39。The whole village soon learnt that a large sum of money had been lost. Sam Benton, the local butcher, had lost his wallet while taking his savings to the postoffice. Sam was sure that the wallet must have been found by one of the villagers, but it was not returned to him. Three months passed, and then one morning, Sam found his wallet outside his front door. It had been wrapped up in newspaper and it contained half the money he had lost, together with a note which said: 39。The strap needs In time, all Sam39。345 for the cost of the trip. The normal price of a ticket is amp。Lesson48 Did you want to tell me something? 你想對(duì)我說(shuō)什么嗎？ I said to the conductor as I got on the bus,39。 I asked. 39。I39。 she said. She gazed at it for some time then added, 39。The Revealer39。 if he picks a leaf, he will die. Many villagers believe that the tree has already claimed a number of victims. The vicar has been asked to have the tree cut down, but so far he has refused. He has pointed out that the tree is a useful source of ine as tourists have been ing from all parts of the country to see it. In spite of all that has been said, the touristshave been picking leaves and cutting their names on the treetrunk. So far, not one of them has been struck down by sudden death! As she walked away, I followed her out of the fair. Lesson62 After the fire 大火之后but they did not steal anything.39。 Two months later, some more money was sent to Sam with another note:39。lesson46 Expensive and unfortable 既昂貴又受罪Tired of sleeping on the floor, a young man in Teheran saved up for years to buy a real bed. For the first time in his life, he became the proud owner of a bed which had springs and a mattress. Because the weather was very hot, he carried the bed on to the roof of his house. He slept very well for the first two nights, but on the third night, a storm blew up. A gust of wind swept the bed off the roof and sent it crashing into the courtyard below. The young man did not wake up until the bed had struck the ground. Although the bed was smashed to pieces, the man was miraculously unhurt. When he woke up, he was still on the mattress. Glancing at the bits of wood and metal that lay around him, the man sadly picked up the mattress and carried it into his house. After he I39。 answered the conductor. 39。t matter,39。 I answered.We have just moved into a new house and I have been working hard all morning. I have been trying to get my new room in order. This has not been easy because I own over a thousand books. To make matters worse, the room is rather small, so I have temporarily put my books on the floor. At the moment, they cover every inch of floor space and I actually have to walk on them to get in or