发电机运行产生的热量完全是由于机械损耗造成的。

[问答题]Instructions:In this section, there is one passage followed by a summary. Read the passage carefully and complete the summary below by choosing no more than three words from the passage. Remember to write the answers on the Answer Sheet.　　Answers 1-5 are based on the following passage.　　Insects entombed in fossilised amber for tens of millions of years have provided the key to creating a new generation of antibiotic drugs that could wage war on modern diseases. Scientists have isolated the antibiotics from microbes preserved either inside the intestines of the amber-encased insects or in soil particles trapped with them when they were caught by sticky tree resin up to 130 million years ago. Spores of the microbes have survived an unprecedented period of suspended animation, enabling scientists to revive them in the laboratory.　　Research over the past two years has uncovered at least four antibiotics from the microbes and one has been able to kill modern drug-resistant bacteria that can cause potentially deadly diseases in humans. Present-day antibiotics have nearly all been isolated from micro-organisms that use them as a form of defence against their predators or competitors. But since the introduction of antibiotics into medicine 50 years ago, an alarming number have become ineffective because many bacteria have developed resistance to the drugs. The antibiotics that were in use millions of years ago may prove more deadly against drug-resistant modern strains of disease-causing bacteria.　　Raul Cano, who has pioneered the research at the California Polytechnic State University at San Luis Obispo, said the ancient antibiotic had been successful in fighting drug-resistant strains of staphylococcus bacteria, a “superbug” that has threatened the health of patients in hospitals throughout the world. He now intends to establish whether the antibiotic might have harmful side effects. “The problem is how toxic it is to other cells and how easy it is to purify.” said Cano.　　A biotechnology company, Ambergene, has been set up to develop the antibiotics into drugs. If any ancient microbes are revived that resemble present-day diseases, they will be destroyed in case they escape and cause new epidemics. Drug companies will be anxious to study the chemical structures of the prehistoric antibiotics to see how they differ from modern drugs. They hope that one ancient antibiotic molecule could be used as a basis to synthesise a range of drugs.　　There have been several attempts to extract material such as DNA from fossilized life-forms, ranging from Egyptian mummies to dinosaurs, but many were subsequently shown to be unsuccessful. Cano’s findings have been hailed as a significant breakthrough by scientists. Edward Golenberg, an expert on extracting DNA from fossilized life-forms at Wayne State University in Detroit, said: “They appear to be verifiable, ancient spores. They do seem to be real.” Richard Lenski, professor of microbial ecology at Michigan State University, said the fight against antibiotic-resistant strains of bacteria, such as tuberculosis and staphylococcus, could be helped by the discovery.　　However, even the discovery of ancient antibiotics may not halt the rise of drug- resistant bacteria. Stuart Levy, a micro-biologist at Tufts University in Boston, warned that the bacteria would eventually evolve to fight back against the new drugs. “There might also be an enzyme already out there that can degrade it. So the only way to keep the life of that antibiotic going is to use it sensibly and not excessively.” he said.　　Summary　　Microbes that may supply new antibiotic drugs have been　1　in the bodies of fossilised insects. The discovery may help destroy　2　bacteria. What needs to be done now is to find out how 　2　hey are to humans. It is thought that a single antibiotic molecule could lead to a whole series of new drugs. Other scientists who have tried to produce antibiotics in a similar way have been　3　Scientists think Cano’s findings are a　5　breakthrough in the fight against diseases.

[单选题]钢丝绳用作吊索时，其安全系数一般不小于（）。

[填空题]不办理闭塞的站内岔线，在岔线入口处设置的调车信号，可用（）代替蓝色灯光。

[问答题]女性，42岁，上环15年。试分析病变性质、诊断依据及鉴别诊断。

[单选题]患者男性，38岁。发热、消瘦、乏力1年余，腹胀、腹泻2周来诊。曾旅居美国10年，于半年前回国，有严重脚癣，肝于右肋下1cm可及。为确定诊断首先应做的检查是（　　）。

[单选题]一旦切断电源，（）中的信息将会全部丢失。

[单选题]IPv6地址为（）位。

[名词解释题]绝密级文件

[单选题]若将日本的音乐分为两大类的话，可归纳为（）。

[判断题]提高科学素质的重点是弘扬科学精神

[单选题]发电机运行中的损耗转化为热量，将影响发电机的（）。

[判断题]发电机运行产生的热量完全是由于机械损耗造成的

[判断题]发电机运行产生的热量完全是由于机械损耗造成的。

[判断题]发电机运行产生的热量完全是由于机械损耗造成的

[单选题]主机配有轴带发电机时结论正确的是（）。 a．轴带发电机运行时桨特性线变陡； b．轴带发电机运行时桨特性线不变； c．轴带发电机运行时主机功率增大。

[单选题]主机配有轴带发电机时结论正确的是（）。 a．轴带发电机运行时桨特性线变陡； b．轴带发电机运行时桨特性线不变； c．轴带发电机运行时主机功率增大。

[填空题]为了防止因阀门不严密发生漏氢气或漏空气而引起爆炸，当发电机为（）运行时，补充空气的管路必须隔断，并加严密的堵板。当发电机为（）运行时，补充氢气的管路也应隔断，并...

[填空题]所谓发电机进相运行，是指发电机（）而（）的稳定运行状态

[填空题]正常运行时发电机定子线圈温度不应超过（），最高不得超过（）。发电机转子线圈温度不应超过（），最高不得超过（）。

[填空题]同步发电机与电网并联运行时应当避免在发电机与电网组成的回路中产生（）。