首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   40篇
  免费   0篇
  国内免费   1篇
安全科学   1篇
废物处理   12篇
综合类   9篇
基础理论   5篇
污染及防治   10篇
评价与监测   1篇
社会与环境   3篇
  2022年   1篇
  2021年   1篇
  2018年   1篇
  2017年   1篇
  2015年   1篇
  2014年   1篇
  2013年   3篇
  2011年   1篇
  2010年   2篇
  2009年   6篇
  2008年   4篇
  2007年   3篇
  2006年   4篇
  2005年   1篇
  2004年   1篇
  2003年   2篇
  2002年   1篇
  2001年   2篇
  1999年   1篇
  1996年   1篇
  1993年   1篇
  1992年   1篇
  1956年   1篇
排序方式: 共有41条查询结果,搜索用时 15 毫秒
21.
To isolate fetal cells from maternal blood, we developed a new method based on galactose-bearing conjugation. Nucleated red blood cells (NRBCs), which highly express galactose on their surface, were selectively attached to a substrate coated with a galactose-containing polymer via soybean agglutinin (SBA), a galactose-specific lectin. Cord blood samples were used to evaluate enrichment efficacy of NRBCs by this method. Blood samples were obtained from 131 pregnant women between 6 and 27 gestational weeks. After preliminary condensation of fetal cells by Ficoll gradient centrifugation, NRBCs were enriched using galactose-positive selection by adjusting SBA concentration. We isolated one to severalhundred NRBCs (mean±SD, 7.8±8.5) in 2.3 ml of peripheral blood samples from 96% of pregnantwomen. The isolated NRBCs were analyzed by a Y-chromosome FISH probe in eight cases carrying male fetuses. Y-signals were detected in all eight cases and more than half of the NRBCs wereoffetal origin. The study demonstrates that our new method using galactose-specific lectin provides effective enrichment of fetal NRBCs allowing non-invasive prenatal diagnosis. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
22.
23.
Japan's basic approach to municipal solid waste (MSW) is (1) waste reduction, (2) promotion of recycling, (3) volume reduction by intermediate treatment, and (4) environmentally sound final disposal. A brief history of legislative trends in waste management is given as background for current waste management and recycling activities. The material recovery rate for MSW collected by local municipalities was only 5.6% in 1996. More than half of MSW, on a volume basis, consists of containers and packages, while great amounts of landfill space are also taken up by bulky wastes such as electric appliances. Therefore, in order to promote recycling and decrease landfill waste, Japan is targeting containers, packages, and electric appliances. A law promoting separate collection and recycling of containers and packages (Packaging Waste Recycling Law) and a law requiring the recycling of specific home electric appliances into new products (Home Electric Appliance Recycling Law) were introduced in June 1995 and June 1998, respectively. These laws are in line with the OECD policy Extended Producer Responsibility (EPR). Received: September 16, 1998 / Accepted: March 10, 1999  相似文献   
24.
In Japan, conflicts regarding the siting of waste disposal facilities occur frequently. In particular, siting of incinerators and landfills has become increasingly difficult because the public is highly concerned about the dioxin issues. Inefficient siting of waste disposal facilities causes several social problems, such as the shortage of waste treatment and disposal facilities, the rising of waste management costs and an increase in the consumption of resources. While dealing with a similar situation, the Chemical Society of Japan adopted a risk communication technique successfully. Hence, the pragmatic use of a risk communication technique is proposed to avoid conflicts and for a smooth information exchange to seek cooperation in waste management. In order to achieve this, a study was conducted to resolve conflicts between residents and the municipality for the selection of site for a solid waste treatment and disposal facility. This study aims to discuss the subject of risk communication for the waste disposal system in Japan. This study is performed through personal interviews and a questionnaire covering opposing parties in the town. As a result of the survey, a risk communication approach for a waste treatment and disposal system is presented in the paper addressing issues such as building of social trust, pragmatic use of the communication process, installation of credible information sources, and environmental education and awareness.  相似文献   
25.
This paper reports on the photodecomposition of aqueous humic acid (HA) by a TiO2-coated ceramic foam filter (TCF) reactor and on the potential for the formation of disinfection byproducts (DBPs) upon chlorination of the photocatalytically treated solutions. This photocatalytic reactor can also be applied to the removal of natural organic matter (NOM) in swamp waters. The proposed photocatalytic reaction system was operated as per standardized methodologies. First, the ability of the TCF to decompose HA (a representative compound of NOM) was evaluated from the changes in the total organic carbon (TOC) and UV254 with the reaction time. Remarkably, TOC removal and UV254 values ranging from 44% to 61% and from 60% to 83%, respectively, were achieved. The potential for the formation of DBPs (total trihalomethane and total haloacetic acid) by chlorination of the phototreated solution was strongly dependent on the TOC removal and UV254 values in the solution. The degree of photodecomposition of NOMs in the swamp water samples and the DBP formation potential showed similar trends as in the case of the standard solutions containing HA. The method used in this study could be effectively used to evaluate the efficiency of TCF for reducing HA and NOM, while suppressing the formation of DBP products.  相似文献   
26.
Subject performance in reading characters on mobile phone liquid crystal displays was researched by using (a) English sentences with 3 or 4 different sizes of characters on 2 types of displays with different resolutions(n = 23; age = 31.0 ± 6.0 years), (b) Japanese characters in 3 different sizes and 2 types of font (n = 98; age = 44.5 ± 18.5 years), and (c) Japanese characters vertically enlarged 1—4 times (n = 120; age = 46.9 ± 18.6 years). Subjective evaluation, reading speed, number of reading errors, and viewing distance were recorded. Readability was higher with higher resolution displays, and with Gothic than with Mincho font in Japanese. Young subjects shortened the viewing distance as characters became smaller, whereas elderly subjects increased the viewing distance irrespective of the size of characters. Characters of 3–5 mm are appropriate for the young but inadequate for the elderly. Readability of Japanese characters improved when they were vertically enlarged to approximately twice the width.  相似文献   
27.
28.
This paper presents an economic evaluation of three typical recycling processes for the five main types of waste electronic home appliances (EHA) (TV set, refrigerator, washing machine, air conditioner and personal computer) in Beijing, the capital of China. The main purpose is to identify the formal management framework with economic feasibility for the waste EHA generated in large municipalities of China. It is found that the advanced technologies, which have mechanical processing units, should be introduced to recover more valuable materials from the waste appliances. Net revenues with a range of 90–240 RMB (Chinese currency unit, 1.0 USD  8.0 RMB) per unit, depend on the type of appliance, could be expected in case of using the most complicated procedures which can separate both metals and plastics from the shredded mixtures. However, the recycling of waste refrigerator and waste washing machine will, respectively, spend about 100 and 6 RMB per unit if solely by simple manual dismantling. Revenues from recycling of the other three types of appliances are positive but quite low in this case. Although positive revenues could be achieved from the isolated evaluation of recycling, the entire management system, which also covers the phases of collection and transportation, is economically infeasible if the waste appliances are bought from the households still at current prices. Based on a survey of the householder's attitude to the cost for waste EHA management, which was conducted earlier, the practical way to construct a formal management system for waste EHA in Beijing is to reduce the citizen's traditional expectation to the values of waste appliances and encourage their transfer to the formal collection system at lower prices.  相似文献   
29.
Summary Two South American polyphagous leaf beetles,Diabrotica speciosa andCerotoma arcuata, selectively accumulated the bitter tasting compound 23,24-dihydrocucurbitacin D in their body after ingesting root tissues of cucurbit plants. Similarly, three Asian Cucurbitaceae-feeding specialists in the genusAulacophora were found to sequester the same compound. Cucurbitacin analogs were shown to deter feeding by a bird predator, indicating an allomonal role for these compounds in cucurbitacin-associated chrysomelid leaf beetles both of New and Old Worlds. The strong affinity to cucurbitacins, selective sequestration of the analogs and consequent protection from predators suggested an ecological adaptation mechanism developed in common among these two geographically isolated subtribes in the Luperini.  相似文献   
30.
Certain enteric viruses that are present in the water environment are potential risk factors of waterborne infections. To better understand the impact of viruses in water, both enteric viruses and their potential indicators should be comparatively investigated. In this study, occurrences of GI- and GII-noroviruses (NoVs), sapovirus (SaV), rotavirus (RoV), Aichi virus 1 (AiV-1), enterovirus (EV), and pepper mild mottle virus (PMMoV) were quantitatively determined in surface water samples in Japan. Additionally, the genotype distribution of GI- and GII-NoVs was determined using a next-generation amplicon sequencing. PMMoV was the most abundant virus regardless of season and location, indicating its usefulness as an indicator for the viral contamination of water. Other potential indicators, AiV and EV, were less abundant than GII-NoV. Viruses other than PMMoV showed seasonality, i.e., EV and other viruses (NoVs, SaV, RoV, and AiV-1) became prevalent during summer and winter, respectively. SaV showed a relatively high abundance at a location that was affected by untreated wastewater. Regarding NoV genotypes, GI.1, GI.2, GI.4, GI.5, GI.6, GII.3, GII.4, GII.6, and GII.17 were found from the surface water samples. GII.4 and GII.17 seemed to have contributed to the high abundance of GII-NoV in the samples. Interestingly, GII.17 strains became prevalent in the water samples before becoming prevalent among gastroenteritis patients in Japan. These findings provide further insights into the properties of viruses as contaminants in the water environment.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号