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991.
Journal of Polymers and the Environment - Although polyvinyl alcohol (PVA) membranes are commonly used for CO2 separation, there is still large development space in mechanical properties and high...  相似文献   
992.
Next-generation herbicides are relatively safe when used properly, but the recommended rates are relatively low, which can lead to overdosing. This study evaluated the responses of soil-dwelling microorganisms and soil enzymes to contamination with the Boreal 58 WG herbicide. The analyzed product contains active ingredients flufenacet and isoxaflutole. All tests were performed under laboratory conditions. The analyzed material was sandy clay. Boreal 58 WG was introduced to soil in four doses. Soil without the addition of the herbicide served as the control. The soil was mixed with the tested herbicide, and its moisture content was maintained at 50% of capillary water capacity. Biochemical and microbiological analyses were performed on experimental days 0, 20, 40, 80 and 160. Accidental contamination of soil with the Boreal 58 WG herbicide led to a relatively minor imbalance in the soil microbiological and biochemical profile. The herbicide dose influenced dehydrogenase activity in only 0.84%, urease activity in 2.04%, β-glucosidase activity in 8.26%, catalase activity in 12.40%, arylsulfatase activity in 12.54%, acid phosphatase activity in 42.11%, numbers of organotrophic bacteria in 18.29%, actinomyces counts in 1.31% and fungi counts in 6.86%.  相似文献   
993.
自然灾害损失评估指标体系的研究   总被引:85,自引:19,他引:85  
本文从自然灾害的社会属性和自然属性出发,对自然灾害损失评估的工作准则、评估指标和方法进行了探索.在自然灾害损失绝对值度量指标——灾度的基础上,进一步提出了标度自然灾害损失的相对量指标——灾损率的概念,并建立了灾损率的等级划分标准,同时还讨论了自然灾害损失的可比价值换算问题。灾度和灾损率概念的确立,使自然灾害对社会财富的损失程度有了较为科学的、定量化的等级描述.灾度和灾损率的概念应用于灾害强度描述、救灾投入、灾害保险、减灾工作评价等方面具有重要的意义。  相似文献   
994.
Ladder brake (Pteris vittata L.) is a newly discovered arsenic hyperaccumulator. No information is available about arsenic effects on ladder brake. This study determined the effects of different arsenic concentrations (50 to 1000 mg kg(-1)) or forms (organic vs. inorganic and arsenite vs. arsenate) applied to soils on growth and arsenic uptake by ladder brake. Young plants were grown in a greenhouse for 12 or 18 wk. Ladder brake was highly tolerant of arsenic and survived in soil containing up to 500 mg As kg(-1). The fact that addition of arsenate up to 100 mg As kg(-1) increased fern biomass by 64 to 107%, coupled with higher arsenic concentration in younger fronds at low soil arsenic concentrations and older fronds at high soil arsenic concentrations, implies that arsenic may be beneficial for fern growth. Addition of 50 mg As kg(-1) was best for fern growth and arsenic accumulation, resulting in the highest fern biomass (3.9 g plant(-1)), bioconcentration factor (up to 63), and translocation factor (up to 25). With an exception of FeAsO4 and AlAsO4, which had the lowest effects due to their low solubility, little difference was observed among other arsenic forms mainly because of arsenic conversion in soil. Aboveground biomass was mostly responsible for accumulation of arsenic by plant (75-99%). Up to 26% of the added arsenic was removed by ladder brake, showing the high efficiency of ladder brake in arsenic removal. The results suggest that ladder brake may be a good candidate to remediate arsenic-contaminated soils.  相似文献   
995.
Huang  Shengyun  Liu  Yannan  Yang  Fan  Wang  Yong  Yu  Ting  Ma  Dongling 《Environmental Chemistry Letters》2022,20(5):3005-3037
Environmental Chemistry Letters - Smart electronics and optoelectronics such as smart windows, touch panels and solar cells have profoundly changed our lives over the last decade, as a result of...  相似文献   
996.
Zhang  Tong  Wang  Ruke  Ma  Linzheng  Liu  Jing  Sun  Jifu  Wang  Bo 《Environmental Chemistry Letters》2022,20(5):2765-2771
Environmental Chemistry Letters - Catalytic dehydrogenative coupling of thiols with amines to produce sulfenamides and disulfides is an important reaction in the industry. Classical synthesis of...  相似文献   
997.
Environmental Science and Pollution Research - In the context of global climate change, studies have focused on the ambient temperature and mortality of cardiovascular diseases (CVDs). However,...  相似文献   
998.
Environmental Science and Pollution Research - This paper discusses interactions between the generation, collection and recovery of used tyres while considering an indicator of their mass...  相似文献   
999.
Environmental Science and Pollution Research - In the present study, the oral bioavailability of cadmium (Cd) in earthworms and leeches was investigated through in vitro physiologically based...  相似文献   
1000.
从现行规范存在的问题入手,提出了确定炼化企业职业健康监护项目与周期的建议,旨在科学合理地指导炼化企业职业健康监护工作的运行操作。  相似文献   
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