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超声波辅助提取毛竹叶中叶绿素的研究 总被引:1,自引:0,他引:1
在超声波作用下,通过使用不同溶剂,研究了毛竹叶中叶绿素的提取方法,并对其提取液中叶绿素的含量进行了检测。结果表明,以丙酮为提取溶剂,料液比为1∶40,超声波提取30min,是从毛竹叶中提取叶绿素的最佳技术工艺。 相似文献
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随着电动汽车大规模的发展,给电网带来了不小的冲击和影响,尤其电动汽车快速充电对电网电压稳定性的影响,准确的负荷模型对研究电压稳定性研究尤其重要。本文分析了电动汽车充电对电网电压稳定性影响。基于快速充电配置建立了电动汽车快速充电的静态负荷模型,通过仿真分析了快速充电器中的整流变换器Rs及Rl对电网电压稳定性的影响。仿真也分析了电动汽车快速充电负载模型与常规的P,Z,I负载模型对电网电压稳定性的影响,结果表明本文所建立的电动汽车负载模型比把电动汽车建立为常规的恒功率、恒流和恒阻抗负载模型有更低的负荷裕度,对电压稳定性影响更高。 相似文献
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基于分光光度法研究了醋酸钠和次氯酸钠对高铁酸钾溶液稳定性的影响。对于1 mmol/L的高铁酸钾溶液,在25℃和pH值12的环境中,醋酸钠能提高其稳定性,当醋酸钠浓度达到10 mmol/L时,高铁酸钾的稳定性最好,静置10h高铁酸钾的留存率约79%;为验证醋酸钠在高铁酸钾分解有机物的反应中是否仍具有稳定高铁酸钾的作用,以降解苯酚为例,当醋酸钠与高铁酸钾摩尔比为5:1时,苯酚的降解率达到最高值88.9%。次氯酸钠对高铁酸钾的稳定性影响实验结果显示,次氯酸钠可以提高高铁酸钾稳定性,次氯酸钠耗尽前,高铁酸钾留存率接近100%。 相似文献
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环境影响评价是环境管理的重要组成部分,为我国的环境管理决策提供重要依据。但在实际工作中,我国的环境管理工作仍然存在一定的问题。本文结合采掘行业的特点,分别从法律层面、设计层面和环境影响评价层面等三个方向进行分析,结合发现的问题提出建议,力求从不同的角度完善相关制度和技术要求。从而使采掘行业的环境管理能全面涵盖采掘行业开发过程,最大程度地减少采掘行业开发过程中的环境影响,完善采掘行业环境影响评价制度,对我国采掘行业生态环境的改善及环境影响评价法制建设起到一定的借鉴意义。 相似文献
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本文利用正交设计研究了浸取剂浓度、浸取温度、浸取时间、料液比对从自粉化料中提取氧化铝的影响;找出了影响提取氧化铝的主要因素;推荐了从自粉化料中提取氧化铝的最佳条件。 相似文献
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Tisdell JG 《Journal of environmental management》2001,62(1):113-120
Water markets are developing as part of a Council of Australian Governments initiative to promote an efficient use of Australia's water resources. The consequences of these policies on river health is yet to be fully understood, but recognised as having significant interrelationships which need to be explored. This paper examines the consequences of introducing trade and allocating water for environmental use in the Border Rivers region of Queensland. The results of this study suggest that: (1) trade in water entitlements is likely to increase the differential between extractive demand and historical flow regimes as extractive water-use concentrates on the most profitable crops, and (2) water markets are likely to limit the effectiveness of water policies aimed at restoring natural flow regimes. As a result, trade-offs between environmental needs and income from extractive use will need to be determined. This work is important and timely in water-policy development demonstrating the linkages and trade-offs between ecological and economic objectives. 相似文献
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This paper introduces a special issue on ‘Corporate Social Responsibility in the extractive industries: experiences from developing countries’. Drawing upon case study analysis from Latin America, sub-Saharan Africa and Asia, the papers in this issue broaden understanding of how multinational mining and oil and gas companies have embraced the CSR challenge and responded to criticisms of their performance in developing countries. This paper provides an introduction to the debate on CSR in the extractive industries in developing countries, reviewing the key issues examined on this subject to date. 相似文献
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T. E. Kolenda 《Resources Policy》1985,11(4):257-266
Much of the world's remaining mineral resources lie within the underdeveloped nations of the Third World. The current crisis of confidence characterized in international investment and trade in extractive resources has become detrimental to both the resource-rich developing countries and the resource-hungry industrialized countries. Japan is one nation that has developed a strategy to foster mutual trust and to restore confidence in the international extractive industries. This paper examines Japan's develop-for-import policy, ‘kaihatsu yunso’, and its design, implementation and effects on securing foreign resources supplies. 相似文献
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Ecosystem management links human activities with the functioning of natural environments over large spatial and temporal scales.
Our examination of Greater Yellowstone and Georges Bank shows similarities exist between human uses, administrative characteristics,
and some biophysical features. Each region faces growing pressures to replace traditional extractive uses with more sustainable
extractive or noncommodity uses coupled with concern about endangered species. Ecosystem management as a set of practical
guidelines for making decisions under evolving expectations is far from complete, and it embodies new demands on individuals
and institutions. In each system these challenges are considered relative to: the public's symbolic understanding of the management
challenge, ecosystem management ambiguities, information availability, information use, administrative setting, and learning
capabilities of governance organizations Progress in making ecosystem management operational may occur as refinements in content
and approach make it an increasingly attractive option for resource users, the public, and government officials. 相似文献
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Daniel S. Papp 《Resources Policy》1979,5(1):51-60
The tenth Soviet five year plan projected increased extraction of mineral resources and improved utilization of those resources. Through 1976 and 1977, actual production closely parallelled planned production in most resources. Even so, 1978 was a critical year for Soviet resources production, and may determine whether the goals of the tenth plan are achieved. Other areas of Soviet resource policy which are discussed include the drive to accelerate Siberian and far eastern development, the effort to improve capital and manpower efficiency, the attempt to improve resource use and reduce non-essential consumption, and the effort to import advanced extractive technology and capital. The article concludes with the observation that with the difficulties facing the Soviet extractive industries, the tenth plan may be the last which projects and strives for a rapid expansion of the Soviet resource base. 相似文献