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511.
Luo Lina Gong Weijia Qin Liyuan Ma Yiwen Ju Wencong Wang Hongyan 《Journal of Material Cycles and Waste Management》2018,20(3):1804-1812
Journal of Material Cycles and Waste Management - Based on the different characteristics of cow manure and rice straw, liquid- and solid-state coupling anaerobic digestion (L-SS-AD) is designed in... 相似文献
512.
Copper uptake by four Elsholtzia ecotypes supplied with varying levels of copper in solution culture 总被引:5,自引:0,他引:5
The effects of copper (Cu) on the yield and Cu uptake of three ecotypes of Elsholtzia splendens and one of Elsholtzia argyi were studied using solution culture. Three Cu concentrations were compared: 0.31 (control), 50 and 100 micromol L(-1). Although E. argyi took up more Cu in the aboveground parts, typical visual symptoms of Cu toxicity appeared when the plants grew in 50 and 100 micromol Cu L(-1). In contrast, plants from all three populations of E. splendens showed high Cu tolerance and substantial shoot Cu accumulation of 58-144 mg kg(-1). Shoot Cu concentrations were about 16-27 times higher than root Cu concentrations. Root-to-shoot ratio of the E. argyi ecotype was halved when Cu was supplied at a level of 100 mg L(-1) compared to the control (0.31 mg L(-1)) but the ratio increased by 6-47% in the three E. splendens ecotypes. The increase in root-to-shoot ratio in E. splendens may be a mechanism by which the plants can tolerate high Cu concentrations. There were few differences in morphology among the three E. splendens ecotypes in response to added Cu. The results are discussed in relation to the possible use of E. splendens as a pioneer species in the phytostabilization of Cu-contaminated soils. 相似文献
513.
职业安全卫生管理体系(简称OHSMS),是完善企业职业安全卫生管理,保证企业职业安全卫生绩效持续改进的科学管理模式。国家经贸委1999年10月发布了《职业安全卫生管理试行标准》后,如何实施和建立职业安全卫生管理体系受到社会和企业的普遍重视与关注。 本系列讲座主要论述:OHSMS的起源、发展与意义;OHSMS的基本概念与理论;OHSMS的基本内容、结构与要素;如何建立和实施OHSMS;如何通过OHSMS的评审和认证等。 相似文献
514.
介绍了钝感炸药 L X- 17的冲击波感度试验。在不同的温度下 ,用不同速度和大小的飞片冲击时 ,测得炸药的起爆阈值 ,发现温度越高 ,速度阈值下降 ,临界起爆面积减小。并对试验结果作了简要分析。 相似文献
515.
罗善明 《中国安全科学学报》2001,11(6):66-68
对有限空间中的淹没非自由射流流压力场的数值解法进行了较为详细的研究和分析 ,并建立了相应的流场力学模型和压力解的第二类边界条件 ,给出了流场的矩形网格几何和边界标记。文中指出 ,精确的压力解只能从泊松形式的压力方程得到 ,且与边界相邻的点和内点应分别采用不同的方程进行求解 相似文献
516.
通过合理利用促进珍稀濒危植物保护 总被引:4,自引:0,他引:4
文章分别以银杏(Ginkgo biloba)、杜仲(Eucommia ulmoides)、水杉(Metasequoia glyptostroboides)、厚朴(Magnolia officinalis)、红豆杉(Taxus wallichiana)等珍稀濒危物种为例,从正反两方面阐述了采用合理利用手段能对珍稀濒危物种的保护起直接作用.提出应该改变人们竭泽而渔的消费观念;加强珍稀濒危物种的育种与栽培研究,提高产业化程度;加强"致死性"利用物种的替代性研究,减少对野生资源的毁灭性利用;加强立法执法,规范市场;注重产业化过程中的知识产权保护与国家资源流失问题等多个方面着手开展工作,最终达到实现利用与保护的和谐统一. 相似文献
517.
518.
Mobilization of heavy metals from contaminated paddy soil by EDDS,EDTA, and elemental sulfur 总被引:1,自引:0,他引:1
Wang G Koopmans GF Song J Temminghoff EJ Luo Y Zhao Q Japenga J 《Environmental geochemistry and health》2007,29(3):221-235
For enhanced phytoextraction, mobilization of heavy metals (HMs) from the soil solid phase to soil pore water is an important
process. A pot incubation experiment mimicking field conditions was conducted to investigate the performance of three soil
additives in mobilizing HMs from contaminated paddy soil (Gleyi-Stagnic Anthrosol): the [S, S]-isomer of ethylenediamine disuccinate
(EDDS) with application rates of 2.3, 4.3, and 11.8 mmol kg−1 of soil, ethylenediamine tetraacetate (EDTA; 1.4, 3.8, and 7.5 mmol kg−1), and elemental sulfur (100, 200, and 400 mmol kg−1). Temporal changes in soil pore water HM and dissolved organic carbon concentrations and pH were monitored for a period of
119 days. EDDS was the most effective additive in mobilizing soil Cu. However, EDDS was only effective during the first 24
to 52 days, and was readily biodegraded with a half-life of 4.1 to 8.7 days. The effectiveness of EDDS decreased at the highest
application rate, most probably as a result of depletion of the readily desorbable Cu pool in soil. EDTA increased the concentrations
of Cu, Pb, Zn, and Cd in the soil pore water, and remained effective during the whole incubation period due to its persistence.
The highest rate of sulfur application led to a decrease in pH to around 4. This increased the pore water HM concentrations,
especially those of Zn and Cd. Concentrations of HMs in the soil pore water can be regulated to a large extent by choosing
the proper application rate of EDDS, EDTA, or sulfur. Hence, a preliminary work such as our pot experiment in combination
with further plant experiments (not included in this study) will provide a good tool to evaluate the applicability of different
soil additives for enhanced phytoextraction of a specific soil. 相似文献
519.
Effects of land use on concentrations of metals in surface soils and ecological risk around Guanting Reservoir,China 总被引:7,自引:0,他引:7
Luo W Lu Y Giesy JP Wang T Shi Y Wang G Xing Y 《Environmental geochemistry and health》2007,29(6):459-471
It is accepted that the historical routine use of agrochemicals may have resulted in undesirable concentrations of metals
in the environment. To investigate and assess the effects of land use on concentrations of heavy metals around the Guanting
Reservoir in China, 52 surface soil samples (depth of 2–10 cm) were taken from areas where four types of land use were practiced
(including arable land, woodland, bare land, orchard land). The metals and metalloids (As, Cr, Ni, Cu, Zn, Cd, and Pb) were
analyzed using inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Significant accumulation of As, Cd, and
Cr was found in soils of arable land. Based on correlation and cluster analysis, it can be concluded that Cd and Zn originate
mainly from phosphate fertilizer, Pb from the use of insecticides, fertilizers, and sewage sludge as well as air deposition,
and Cu from copper-based fungicides, while As, Ni and Cr might come from parent soil material. According to an ecological
risk analysis of metals based on the ecological index suggested by Hakanson, the four types of land can be ranked by severity
of ecological risk as follows: arable land > woodland > bare land > orchard land, with a high ecological risk of Cd for all
four types. Management measures for land use planners for avoiding water, soil, and sediment pollution caused by metals around
the Guanting Reservoir are presented. 相似文献
520.