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61.
Catalytic water phase processes as an environmental application is a relatively novel subject with tremendous potential in the near future. This review of 120 references presents the wide scale of heterogeneous water phase applications studied mainly within past five years. Both oxidation and hydrogenation processes are included as well as TiO2 assisted photocatalysis. According to the references, heterogeneous catalysis is developing rapidly. New bimetallic catalysts and supports with higher surface area have improved catalytic efficiency in both oxidation and hydrogenation processes. It also seems that study on use of some waste materials such as red mud as catalyst is a very progressive field. On the whole, the chemical aspects are pretty well known, but the catalyst durability, and in many cases activity as well, has to be improved. 相似文献
62.
加强环境监测质量管理人员队伍建设的思考 总被引:12,自引:0,他引:12
袁力 《环境监测管理与技术》2010,22(5):5-7
简述了环境监测质量管理人员队伍存在的问题。指出建立优良的质量管理人员队伍是规范环境监测质量管理工作、强化环境监测质量管理能力、提高环境监测质量管理水平的坚实基础。提出了建立完善环境监测质量管理人员队伍的设想,应梳理总结,建立质量管理理论体系;明确职责,完善质量管理人员队伍体系;分清层次,建立有效的培训机制。 相似文献
63.
区域开发具有较大的不确定性,并且占地面积大、开发的内容广、性质复杂、建设周期长,通常的区域开发都有可能涉及到工业、城建、商业、人居、市政等多个领域的开发活动,所以区域开发必须结合区域开发的特征,准确识别其可能对区域内及其周边的空气环境、地下水质量、地表水水质及水文条件、声环境、土壤、植被、地形地貌等自然环境和人口、交通、经济结构等社会环境等产生的影响,并采取发展循环经济,减少污染生成的源头控制措施;科学规划产业结构,合理布局的预防性措施;源内达标、区域集中控制的污染治理措施;实施清洁生产、总量控制,推进区域环境与经济的持续发展。 相似文献
64.
介绍了中国电器科学研究院近期研制开发的电镀、氧化等金属表面处理新型生产线。对生产线各相关系统进行研究,通过改进与创新,达到清洁、节能、智能化等目的。 相似文献
65.
River damming provides a dominant human impact on river environments worldwide, and while local impacts of reservoir flooding
are immediate, subsequent ecological impacts downstream can be extensive. In this article, we assess seven research strategies
for analyzing the impacts of dams and river flow regulation on riparian ecosystems. These include spatial comparisons of (1)
upstream versus downstream reaches, (2) progressive downstream patterns, or (3) the dammed river versus an adjacent free-flowing
or differently regulated river(s). Temporal comparisons consider (4) pre- versus post-dam, or (5) sequential post-dam conditions.
However, spatial comparisons are complicated by the fact that dams are not randomly located, and temporal comparisons are
commonly limited by sparse historic information. As a result, comparative approaches are often correlative and vulnerable
to confounding factors. To complement these analyses, (6) flow or sediment modifications can be implemented to test causal
associations. Finally, (7) process-based modeling represents a predictive approach incorporating hydrogeomorphic processes
and their biological consequences. In a case study of Hells Canyon, the upstream versus downstream comparison is confounded
by a dramatic geomorphic transition. Comparison of the multiple reaches below the dams should be useful, and the comparison
of Snake River with the adjacent free-flowing Salmon River may provide the strongest spatial comparison. A pre- versus post-dam
comparison would provide the most direct study approach, but pre-dam information is limited to historic reports and archival
photographs. We conclude that multiple study approaches are essential to provide confident interpretations of ecological impacts
downstream from dams, and propose a comprehensive study for Hells Canyon that integrates multiple research strategies. 相似文献
66.
Volunteer monitoring of natural resources is promoted for its ability to increase public awareness, to provide valuable knowledge, and to encourage policy change that promotes ecosystem health. We used the case of volunteer macroinvertebrate monitoring (VMM) in streams to investigate whether the quality of data collected is correlated with data use and organizers' perception of whether they have achieved these outcomes. We examined the relation between site and group characteristics, data quality, data use, and perceived outcomes (education, social capital, and policy change). We found that group size and the degree to which citizen groups perform tasks on their own (rather than aided by professionals) positively correlated with the quality of data collected. Group size and number of years monitoring positively influenced whether a group used their data. While one might expect that groups committed to collecting good-quality data would be more likely to use it, there was no relation between data quality and data use, and no relation between data quality and perceived outcomes. More data use was, however, correlated with a group's feeling of connection to a network of engaged citizens and professionals. While VMM may hold promise for bringing citizens and scientists together to work on joint conservation agendas, our data illustrate that data quality does not correlate with a volunteer group's desire to use their data to promote regulatory change. Therefore, we encourage scientists and citizens alike to recognize this potential disconnect and strive to be explicit about the role of data in conservation efforts. 相似文献
67.
Because American national forests are managed for all citizens, it is important that researchers explore the differences and
similarities between citizens living both near and far from publicly managed land. We surveyed residents living at various
distances from nationally managed land to collect resident perceptions of different forest fire-management techniques, to
determine public preferences for these techniques, and to examine the motivations behind these preferences. Participants both
close to and far away from national forests tended to favor a multipronged approach to fire management by preferring the use
of a combination of two or more fire-management techniques. There were no significant differences by proximity in participants’
self-rated emotions, types of fire-management techniques preferred, or the reasons and rationales for their preferred fire-management
technique(s), indicating that the proximity variable may not be as significant as previously thought. 相似文献
68.
Snowmobile use in Yellowstone National Park has been shown to impact air quality, with implications for the safety and welfare
of Park staff and other Park resource values. Localized impacts have been documented at several high-use sites in the Park,
but the broader spatial variability of snowmobile emissions and air quality was not understood. Measurements of 87 volatile
organic compounds (VOCs) were made for ambient air sampled across the Park and West Yellowstone, Montana, during 2 days of
the 2002–2003 winter use season, 1 year before the implementation of a new snowmobile policy. The data were compared with
similar data from pristine West Coast sites at similar latitudes. Backward trajectories of local air masses, alkyl nitrate-parent
alkane ratios, and atmospheric soundings were used to identify the VOC sources and assess their impact. Different oversnow
vehicle types used in the Park were sampled to determine their relative influence on air mass pollutant composition. VOCs
were of local origin and demonstrated strong spatiotemporal variability that is primarily influenced by levels of snowmobile
traffic on given road segments at different times of day. High levels of snowmobile traffic in and around West Yellowstone
produced consistently high levels of benzene, toluene, and carbon monoxide. 相似文献
69.
土壤锑污染对桑树的影响初探 总被引:1,自引:0,他引:1
运用盆栽实验和实验分析方法,研究了土壤锑(Sb)污染对桑叶品质的影响,揭示了桑树对土壤锑的耐性机制。在土壤中分别添加三价锑15mg/kg、40mg/kg、80mg/kg、120mg/kg、160mg/kg和300mg/kg,以植物生长指标及生理指标为测试指标,实验周期60d。实验结果表明,低浓度Sb处理(<40mg/kg)对桑树生长有促进作用;随着土壤Sb浓度增高(40—300mg/kg),它对桑树产生抑制效应。但当土壤锑浓度不超过160mg/kg时,桑树对土壤锑污染有一定的耐性,其耐性指数>0.8。土壤锑污染对桑叶叶绿素含量、淀粉含量和可溶性糖含量影响不显著,桑叶中的锑含量随土壤锑含量的增加而增多。 相似文献
70.