首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Biogas: a Solution to Many Problems In almost all developing countries, the lack of adequate supplies of cheap, convenient a
Biogas: a Solution to Many Problems In almost all developing countries, the lack of adequate supplies of cheap, convenient a
admin
2018-01-25
17
问题
Biogas: a Solution to Many Problems
In almost all developing countries, the lack of adequate supplies of cheap, convenient and reliable fuel is a major problem. Rural communities depend largely on kerosene, wood and dung for their cooking and lighting needs. But kerosene is now priced out of reach of many people and wood, except in heavily forested areas, is in short supply. The search for firewood occupies a large part of the working day and has resulted in widespread deforestation.
Dung is in constant supply wherever there are farm animals and, when dried, it is convenient to store and use. But burning dung destroys its value as fertilizer, thus depriving the soil of a much needed source of humus and nitrogen.
Rural areas of developing countries are also plagued by a lack of adequate sanitation. Improper waste disposal spreads disease, contaminates water sources and provides breeding grounds for disease-carrying insect.
The problems of improving environmental hygiene, conserving resources and finding alternative sources of fuel may be unrelated. Their solutions, however, are not, as many countries experimenting with biogas technology are discovering. Biogas, a mixture of methane and carbon dioxide, is produced by the fermentation of organic matter. The process of anaerobic fermentation is a natural one occurring whenever living matter decomposes. By containing the matter—and the process—in a digester or biogas plant, the combustible gas can be trapped and used as fuel for household lighting and cooking. The digested slurry that remains can be used on the land as a soil conditioner and fertilizer.
Biogas plants have attracted much interest in recent years and they are in use in several Asian countries: 36,000 are reported in rural areas of India, 27,000 in Korea and more than 80,000 in China. In most countries the value of the gas has been the prime factor leading to their adoption: 70 per cent of India’s plants, for instance, were built during the energy and fertilizer crisis of 1975—1976— although their use in that country dates back to 1951. Similarly in Thailand and Korea, biogas is being investigated as an alternative to costly charcoal and to save compost materials from being burned.
In Japan and China, reducing pollution from animal wastes has been an important factor. Privies , hen houses and pigpens are built in proximity to the fermentation chamber in China. Examinations of the digested slurry have shown that the total number of parasite eggs was reduced by 93. 6 per cent, hookworms by 99 per cent and no schistosome flukes were found.
The greatest benefits from biogas systems, however, are probably to be derived from the ma-nurial value of the slurry, although it is not widely used outside of India and China. Vegetable farmers near Calcutta found that the digested slurry produced bigger and better tasting peas than did other fertilizers and the weight of root vegetables increased by nearly 300 per cent.
Questions 71 to 75
Complete the summary below with information from the passage, using no more than three words for each blank.
The production of biogas by fermentation of animal and vegetable wastes is a technology that has been largely developed and used in the【E1】____countries. Only very recently have scientists in the industrialized nations begun to show an interest—presumably because of the " energy【E2】____".
Family-sized-biogas【E3】____first came into widespread use in India in the 1950s in an effort to make a cleaner and more efficient use of cattle dung. The programme really expanded in the 1970s, and today there are as many as 100,000 plants throughout the world. Most are in domestic use to provide fuel for plants, but some larger units are operated in order to recycle wastes, supply fertilizer, control pollution and improve【E4】____. One Chinese study has shown that digestion of animal【E5】______in the airtight digesters greatly reduces health hazards from parasitic diseases.
One Indian study has estimated that the value of the fertilizer obtained is in itself greater than the cost of producing the biogas. Thus, the system is economically sound, in addition to other benefits such as a cleaner, healthier environment.
【E2】
选项
答案
crisis
解析
(从题干中的presumably(推测起来,大概)可知,该题属常识推理题。第四段,沼气事实上可以帮助conserving resources and finding alternative sources of fuel,可以猜想工业化国家对沼气感兴趣可能是由于能源危机,即energy crisis。)
转载请注明原文地址:https://kaotiyun.com/show/RSyK777K
本试题收录于:
A类竞赛(研究生)题库大学生英语竞赛(NECCS)分类
0
A类竞赛(研究生)
大学生英语竞赛(NECCS)
相关试题推荐
Thespokesmanadmittedthatthegovernment’sthoughtlesspolicyhadcausedacrisisthat________.
Researchshowsthatifwedon’t__________enoughvitaminD,wewilldevelophealthproblems.
ChillinghamisafamouscastleinEngland.Manypeoplethinkthiscastleishaunted.Theysayghostscanoftenbeseenontheca
Formanystudents,choosingacareeristhemostimportantlifedecisiontheymusttakeatschool.But,choosingtherightcaree
Formanystudents,choosingacareeristhemostimportantlifedecisiontheymusttakeatschool.But,choosingtherightcaree
ClassesinStudioeveryafternoonRoom51on【21】OnFridayscanuse【22】forprivatestudyExtracourses:Monda
Americancigarettesalesareexpectedtodecreaseby______bytheendofthedecade.
WhichofthefollowingstatementsistrueabouttheKnowledge?
WhichAmericanPresidentsaid:"Weholdthesetruthstobeself-evidentthatallmenarecreatedequal"?
JanetJacksontoldtheaudienceattheBlackEntertainmentTelevisionAwardsthattheentireJacksonfamilyhadwantedtoattend
随机试题
A.温邪犯表,肺卫失宣B.邪热壅肺,肺气郁闭C.热灼营阴,心神被扰D.邪入气分,热炽伤津卫分证的主要病机是
以下哪项为复合感觉
在化妆品的pH测定中,以下注意事项中,属于不必需的或原则性错误的是
在对瘿病肿块扪诊时,除对其肿块位置、数目、硬度、光滑度、活动度、界限进行重点检查外,还应注意的是
根据我国税法,关于累进税率的说法,正确的是()。
下列方法中,能够进行质量控制的静态方法是()。
某石油企业为增值税一般纳税人,本月开采原油9000吨,其中当月销售6000吨,取得不含税销售收入2700万元,同时还向购买方收取延期付款利息3.51万元;取得运输企业的增值税专用发票注明的运费9万元,增值税税额0.99万元。已知原油的资源税税率为6%,则该
某企业每年需要耗用2000件的某种物资,每次的订货成本为10元,每件物资的年保管费率为10%,该物资的单价随每次的订货量增加而略有下降。当订货批量不超过60件时,单价为30元;订货批量在60至100件之间时的单价为25元;订货批量超过100件时的单价为20
WhereDidAlltheShipsGo?TheBermudaTriangleisone【51】thegreatestmysteriesofthesea.Inthistriangularareabetween
WhenIenteredtheroom,Ifoundmecup(break)______onthetable.
最新回复
(
0
)