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121.
ACF表面化学官能团对影响脱硫性能的研究进展   总被引:1,自引:0,他引:1  
活性炭纤维(ACF)作为第三代活性炭,是一种新型的高效吸附剂和催化剂。它具有独特的物理性能和化学性能,对烟气中的SO2具有很强的吸附和催化氧化作用,因此作为烟气脱硫方面极具前景的催化剂而受到人们的普遍关注。以聚丙烯腈基活性炭纤维(PAN-ACF)为代表,主要深入探讨了ACF表面化学官能团对脱硫性能的影响。  相似文献   
122.
Introduction: The objective of this study was to analyze which factors (including factors pertaining to the individual, the household, and the local area) increase the risk of fall injuries for the three age groups with the highest risk for fall injuries in Sweden. Method: The study combined longitudinal data covering the period 1999–2013 from several different official registries from Statistics Sweden as well as from the Swedish health care system and fitted the models to data using mixed model regressions. Results: Three age groups had a markedly heightened risk for fall injuries: 1–3-year olds, 12–14 year olds, and the elderly (65+). The home was the most common location for fall injuries, as about 40% of all fall injuries occur in the home. Only for the elderly strong predictors for fall injuries were found, and these were: age, single household, and special housing. Conclusions: There is preventive potential in the special residences for the elderly and disabled. People living in these special residences make up a strongly selected group that needs extra safe environments. Our findings indicate that their needs are currently not meet. Practical applications: Design of special residences for the elderly and disabled should aim at reducing the consequences of falling.  相似文献   
123.
抓好班组安全建设 ,必须做到领导、思想教育、安全管理三个到位  相似文献   
124.
Problem: In response to the demands of competitiveness, there has been a proliferation of management delayering in order to move responsibility to those people carrying out the operations and to focus on working as a team. Teams can be managed in different ways: using supervisors, team leaders, or self-managed. The management of health and safety and other business risks is dependent on the way in which the team is managed. Method: This study has assessed, through the use of semistructured interviews, how UK manufacturing companies have addressed a range of health and safety management issues (i.e., the setting, communication, and measurement of company objectives, employee participation and empowerment, and risk assessment) in relation to different styles of group working (i.e., supervised groups, groups with team leaders, and self-managed groups). Discussion: Although the differences are not always significant, it is noticeable that within organizations using supervised work environments, there is a lack of communication of specific health and safety information, little involvement and participation in safety activities, and a greater reliance on the safety function. However, in organizations using team leaders and self-managed groups, there is evidence of greater management involvement, more open communication, and greater employee involvement in health and safety, although empowerment in its true sense was still limited in these organizations. Impact on industry: The results obtained illustrate the impact of different working groups on the management of health and safety in the UK manufacturing sector.  相似文献   
125.
Fetuses of women with alloantibodies to RhD (D) are at risk from hemolytic disease of the fetus and newborn, but only if the fetal red cells are D-positive. In such pregnancies, it is beneficial to determine fetal D type, as this will affect the management of the pregnancy. It is possible to predict, with a high level of accuracy, fetal blood group phenotypes from genotyping tests on fetal DNA. The best source is the small quantity of fetal DNA in the blood of pregnant women, as this avoids the requirement for invasive procedures of amniocentesis or chorionic villus sampling (CVS). Many laboratories worldwide now provide noninvasive fetal D genotyping as a routine service for alloimmunized women, and some also test for c, E, C and K. In many countries, anti-D immunoglobulin injections are offered to D-negative pregnant women, to reduce the chances of prenatal immunization, even though up to 40% of these women will have a D-negative fetus. High-throughput, noninvasive fetal D genotyping technologies are being developed so that unnecessary treatment of pregnant women can be avoided. Trials suggest that fetal D typing of all D-negative pregnant women is feasible and should become common practice in the near future. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
126.
Increasing food demands are causing rapid transitions in farming systems, often involving intensified land and resource use. While transitioning has benefits regarding poverty alleviation and food outputs, it also causes environmental and social issues over time. This study aims to understand the transitions in farming systems in a region in Telangana, from 1997 to 2015, and their effect on livestock rearing and smallholder livelihoods. We also examine the impact of the transitions on lower caste groups and women in particular. We collected data using a combination of methods, i.e., a household survey, focus group discussions, and secondary data sources, to build a comprehensive picture of the transitions in the region. We found that subsistence mixed farming systems transitioned to market-orientated specialized systems over a short time span. As the transition process gained momentum, households either intensified their production or got marginalized. Technological interventions, development programs with integrated approaches, and market demand for certain agricultural produce triggered increased regional production but also led to the scarcity of water, land, and labor. The transitions marginalized some of the households, changed the role of livestock in farming, and have been inclusive of both lower caste groups and women in terms of increased ownership of large ruminants and access to technologies. However, for women specifically, further increase in workload in the context of farming is also found.  相似文献   
127.
ABSTRACT: Collaborative watershed groups have formed at a significant rate throughout the United States in the last decade. Data on these groups, however, has been largely anecdotal and lacking in rigorous examination of the relationship between group formation, membership, process, and group effectiveness. Using a mail survey, Oregon watershed group participants were asked to identify who initiated the formation of the group, how efficiently the group formed, how the group determines membership, what decision making method the group uses, and how members perceive the group's effectiveness. Findings indicated that a majority believe that, because of their participation in a watershed group, they better understand issues in the watershed and the perspectives of others, but less than half believe that relationships with government decision makers or physical conditions in the watershed have improved. Members of citizen initiated groups rated their groups higher than government initiated groups on addressing difficult or controversial issues. Members of groups that use consensus responded most positively on whether the group gives fair consideration to dissenting opinions. Overall, groups with restricted membership systems rated themselves lowest on involving key decision making groups, timeliness in addressing issues, and overall effectiveness. These results raise concerns about this type of group membership system.  相似文献   
128.
This paper uses GIS-based mapping tools and economic valuation of ecosystem goods and services to explore the social dimension of biodiversity policy. We investigate the linkages between biodiversity, ecosystem service values, and socio-economic vulnerability indicators in a spatially explicit framework and at different geographic scales. Our focus is on Europe, where biodiversity and ecosystem benefits have been well studied for many ecosystems, such as forests, coastal ecosystems and freshwater wetlands. The analysis focuses in particular on rural agricultural areas and remote mountainous regions accounting for the differences across various income groups, both at national and regional levels. The results of the study provide useful insights for EU policymakers in designing policy instruments that can promote biodiversity conservation and prevent natural resource degradation, on the one hand, while contributing to social stability and human livelihoods, on the other hand.  相似文献   
129.
研究岩溶与非岩溶区土壤团聚体中微生物群落结构和功能类群异同,可以为揭示岩溶区土壤有机微生物与团粒结构稳定之间的互作机制提供理论依据.以岩溶与非岩溶稻田的耕层土壤为研究对象,采用湿筛法将团聚体分为大团聚体(0.25~2 mm)、微团聚体(0.053~0.25 mm)和粉、黏粒组分(<0.053 mm),通过高通量测序对土壤团聚体微生物群落结构进行分析,并采用共现网络分析细菌关键类群以及利用FAPROTAX进行功能预测.结果表明,(1)岩溶区大团聚体质量占比为30.94%,团聚体平均质量直径和几何平均直径分别为0.41 mm和0.15 mm,这3个项目均显著高于非岩溶区,表明岩溶区的环境有利于团聚体的形成;(2)岩溶区3个粒径团聚体的酸杆菌门、变形菌门、酸杆菌(Gp3、 Gp4和Gp6)和鞘氨醇单胞菌属等相对丰度均高于非岩溶区.岩溶区微团聚体中的绿弯菌门的相对丰度(6.13%)显著高于粉、黏粒组分(2.79%);(3)共现网络分析表明,变形菌门和酸杆菌门为3个粒径团聚体中的关键类群.岩溶区微团聚体中细菌正相关边(65.5%)最高,相互关系多为协同关系;(4)岩溶区土壤3个粒径团聚体中...  相似文献   
130.
In this work, zinc ferrite spinel with different zinc contents (ZnxFe3-xO4) was synthesized by a hydrothermal method and used for removing As(V) in aqueous solution. X-ray diffraction (XRD) results indicated that in the crystal structure of ZnxFe3-xO4, the zinc atoms tended to occupy the octahedral sites for x?<?0.6 and diffused into the tetrahedral sites gradually with x?>?0.6. The size of ZnxFe3-xO4 crystallites increased with the increasing zinc content. Batch adsorption experiments showed that the adsorption isotherms could be well described by the Langmuir model, while the adsorption kinetics followed the pseudo-second-order kinetic model. Zinc ferrite exhibited the highest adsorption capacity towards As(V) when x?=?0.6. Study of the mechanism indicated that doping with zinc increased the number of surface hydroxyl groups on ferrite spinel, and thus enhanced the adsorption capacity when x?=?0.6. This work revealed the effects of doping site and content of metal atoms on the adsorption ability of ferrite spinel towards As(V).  相似文献   
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