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1.
我国农村有机废弃物资源及沼气潜力 总被引：1，自引：0，他引：1
张无敌刘士清周斌何彩云 《资源科学》1997,19(1):67-71
我国农村每年有各类秸秆6.2×108t，除去40%用于饲料和其他工业原料外，若全部用于沼气发酵，每年可产沼气744×108m3。每年农村可有各种畜禽粪便34.781×108t（TS为20%），可产沼气1536.21×108m3。每年农村有人粪尿1.7×108t，可产沼气88.4×108t3。 相似文献
2.
生物质秸秆资源发电的综合效益量化分析以江苏省射阳县秸秆发电厂为例 总被引：7，自引：1，他引：6
人口多,资源短缺是我国的基本国情.如何利用可再生能源日益成为研究的热点,生物质秸秆资源作为可再生能源的重要分支,以此为原料进行发电的研究和探索一直进行着,并取得阶段性成果.但利用生物质秸秆资源发电的综合效益尚无定量结论,本研究以此为切入点,试图在秸秆资源发电的综合效益量化上取得突破.首先分析我国生物质秸秆资源现状及利用情况,然后从经济、生态、社会3个视角分析了生物质秸秆资源发电的综合效益,进而构建秸秆发电的综合效益模型对其量化,并进行实证分析.研究结果表明:①我国生物质秸秆资源发电的前景十分广阔,长远看综合效益可观,但其综合效益具有滞后性,近期综合效益不太明显;②实证分析结果表明.装机容量为1×25MW、每年燃烧棉花秸秆12.31 ×104t、年供电量1.37×108kWh的秸秆发电厂一般6.23年后才能取得明显的综合效益,长期来看其综合效益可达46 277.50×104元,由此推论若将全国的生物质秸秆资源充分利用起来,发电的综合效益可高达11 822.72×108元. 相似文献
3.
我国南方作物秸秆资源丰富，具有种类多、数量大、质量高、分布广的特点：目前，南方作物秸秆资源主要用作燃料、饲料、肥料和工业原料等多种用途，但其利用上明显存在“三低一重”的特点（即利用率低、转化率低、经济效益低和环境污染严重）。今后，开发利用南方作物秸秆资源，必须做到：1、充分提高认识，切实转变观念；2、扩大秸秆生产，增加秸秆来源；3、充分利用秸秆，避免一切浪费；4、合理利用秸秆，提高转化效率；5、综合开发利用，提高三大效益。 相似文献
4.
我国南方作物秸秆资源丰富，具有种类多、数量大、质量高、分布广的特点；目前，南方作物秸秆资源主要用作燃料、饲料、肥料和工业原料等多种用途，但其利用上明显存在“三低一重”的特点（即利用率低、转化率低、经济效益低和环境污染严重）。今后，开发利用南方作物秸秆资源，必须做到：①充分提高认识，切实转变观念；②扩大秸秆生产，增加秸秆来源；③充分利用秸秆，避免一切浪费；④合理利用秸秆，提高转化效率；⑤综合开发利用，提高三大效益 相似文献
5.
中国大陆秸秆露天焚烧的量的估算 总被引：62，自引：0，他引：62
根据2001年～2003年各省市农作物的产量和谷草比值，计算了全国和各省市农业秸秆的总量，全国农业秸秆产生量约6×108t/年，其中稻谷、小麦、玉米3种秸秆共占总量的76%左右；结合各地区所处气候带、农村生活水平、植被覆盖现状和各种农作物的主要产量等，预估了农业秸秆被露天焚烧的比例，为0～50%，并由此计算了各年份我国大陆农业秸秆被露天焚烧的总量及各省市的清单，并进一步细化到县、区级行政区，使用地理信息系统给出了0.2°×0.2°的单位面积秸秆被露天焚烧量的分布图。研究表明，由于经济发展水平和生活习惯的不同，农业秸秆被露天焚烧的量在地区间的分布不均衡，量较大的包括华东、东北地区的各省市；单位面积秸秆被露天焚烧的量较高的地区由东北至华东呈带状分布。最后，提出了控制秸秆露天焚烧的措施。 相似文献
6.
中国农村户用沼气主要发酵原料资源量的估算 总被引：9，自引：1，他引：8
农村户用沼气池运行的发酵原料主要有农作物秸秆、畜禽粪便和人粪尿,本文对这几种原料的资源量进行了估算,并分析了其分布状况。结果表明,1999年～2006年农作物秸秆的总量保持在（5.5～6.4）×108t,以稻谷秸秆、玉米秸秆和小麦秸秆为主（约3/4）;畜禽粪便的总量从 33.9×108t稳步增至41.2×108t,畜类粪便中以牛粪（约46％）和猪粪（约35%）为主,禽类粪便（约3.0×108t）中以鸡粪（约75%）为主;人粪尿总量随着农村人口变迁,从4.5×108t减至4.0×108t。3种类型中,以畜禽粪便为主,其比例从76%逐年上升至80%。河南、四川、山东、河北、湖南五省各种主要发酵原料的数量均位居前列,从其总量和比例关系来看,为发展沼气提供了充足和较均衡的原料,为大规模发展沼气提供了有利条件。 相似文献
7.
中国不同区域化肥资源利用特征与合理配置 总被引：34，自引：4，他引：30
本文把中国分成东部、中部和西部地区3个区域,根据1980－1995年的农业统计资料分析了不同区域化肥施用变化特征及其与粮食生产的关系。计算了在现有施肥技术水平和施肥条件下,不同区域的化肥边际产量,并估算了边际产量为0时全国化肥总需求量和可能达到的粮食产量,分别是4.649×104t和62378×104t。比较了不同区域施用化肥的增产效果,在此基础上讨论了在区域间进行化肥资源合理配置的实践意义。 相似文献
8.
福州市垃圾处理系统优化设计及规划 总被引：2，自引：1，他引：2
随着经济的发展和城市居民生活水平的提高，城市生活垃圾已经成为当前世界性的严重公害之一。如何优化城市生活垃圾治理系统是解决“垃圾围城”的热点问题。从理论上讲，城市生活垃圾处理模型是一个包含费用最小、处理风险最小、综合效益（社会效益、环境效益、经济效益）最大这3个目标的非线性规划模型。但是，除各处理费用因素可直接量化外，处理风险、综合效益的量化较困难。该文应用运筹学理论，依据处理费用最小、综合效益最大的原则建立多目标优化模型，并结合福州市实际情况，对福州市近、中期城市生活垃圾治理系统进行优化设计。优化结果分析表明，福州市城市生活垃圾较为理想的处理方式为：到2005年，用于堆肥28.59×104t?a-1，填埋36.81×104t?a-1；到2010年，用于堆肥36.97×104t?a-1，填埋30.67×104t?a-1, 焚烧5.40×104t?a-1。因此，福州市要构筑较为理想的城市生活垃圾处理系统，近2a需完成红庙岭二号库区卫生填埋场的建设，填埋量为1000t?d -1；2005年需建成制肥厂一座，生产规模为1000t?d -1；2010年需建焚烧厂一座，焚烧量为200t?d -1。 相似文献
9.
气候变化对中国主要农作物秸秆资源的影响 总被引：2，自引：0，他引：2
生物质能在缓解能源紧张,降低气候变化影响方面具有广阔的发展前景。农作物秸秆作为其丰富重要的原料之一,它的有效开发和利用,将对我国生物质资源的综合利用有重要影响。气候变化会影响农作物秸秆产量,本研究利用CERES作物模型模拟了基本气候BS情景下(1961年-1990年)和SRES温室气体排放方案下B2情景的(2011年-2100年)我国三大粮食作物水稻、小麦、玉米的秸秆生产量,分析并预测了未来气候变化对其秸秆生产量的影响,结果表明:①作物秸秆生产总量表现为先降低(2020s)后增加(2050s、2080s)的趋势,其中水稻的秸秆单产和总量将下降,而小麦和玉米的秸秆单产、总量则有增加趋势,尤其是小麦增加幅度更大;②未来气候变化将增大作物秸秆生产总量的年际波动,影响秸秆利用量的稳定性;③华北地区是未来三大作物秸秆总量增加的主要区域,有利于秸秆资源的开发和利用,而东北的东部地区秸秆总量表现为大幅度的降低。本文成果属初步研究,存在一定的不确定性,今后需要继续深入探讨,逐步降低研究中的不确定性。 相似文献
10.
中国湿地资源及其保护研究 总被引：40，自引：2，他引：38
中国湿地类型多,包括《湿地公约》列出的全部湿地类型。另外还包括青藏高原湿地,共计38种。湿地面积大,据最新统计,总面积约7 969 ×104 hm2 ,包括人工湿地3 447 ×104 hm2 ,自然湿地4 522 ×104 hm2 ,居世界第三位。湿地中蕴藏有丰富的生物资源、泥炭资源、水资源,而其本身又是重要的土地资源。湿地在调节环境,保持小气候稳定,维持区域生态平衡等方面发挥重要作用,对改善我国生态环境和保障社会经济发展具有重要意义。但随着经济的发展,湿地资源面临严重的威胁。湿地面积不断减少,湿地珍稀动植物种类、数量不断下降,湿地污染、破坏严重。湿地资源到了必须加以重视和保护的时候。本文在全面研究中国湿地资源现状基础上,分析了湿地面临的主要威胁,最后提出湿地保护及其对策。意在加强湿地资源的保护与合理利用,使得湿地资源得以永续利用,造福于后世。 相似文献
11.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
12.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
13.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
14.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
15.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
16.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
17.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献
18.
Milton Mueller 《The Information Society》2001,17(3):151-163
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP. 相似文献
19.
Prof. Raymond C.K. Chen a neuropsychologist with the CAS Institute of Psychology has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.…… 《中国科学院院刊(英文版)》2008,22(1):15-15
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology. 相似文献
20.
Prof. SUN Changpu from the CAS Institute of Theoretical Physics coworkers from University of Basel in Switzerland have worked out a way - at least in theory - to split a beam of molecules according to their chirality. The technique involves passing the molecules through three different laser beams is similar to the famous Stern-Gerlach effect whereby a beam of atoms passing through a magnetic field is split in two according to the atoms' spin states 《中国科学院院刊(英文版)》2008,22(1):23-23
Prof. SUN Changpu from the CAS Institute of Theoretical Physics and coworkers from University of Basel in Switzerland have worked out a way --at least in theory --to split a beam of molecules according to their chirality. The technique involves passing the molecules through three different laser beams and is similar to the famous Stern-Gerlach effect, whereby a beam of atoms passing through a magnetic field is split in two according to the atoms＇ spin states （Phys. Rev. Lett. 99 130403）. 相似文献