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951.
The effects of simulated acid rain with pH values of 6.63 (control, 4.5, 3.0, and 2.0 on saplings of Pinus massoniana and Cunninghamia lanceolate, were studied. The results showed that the pH of C.lanceolate, leaf sap and soil decreased as the acidity of rainfall increased. The acid rain with very low pH had significant effects on the photosynthetic rates per plant, but not on that of the per unit weight of dry leaves. The respiration rates of the two species were stimulated. Root and leaf boimass, but not stem biomass, were also reduced tremendously during a seven months period.  相似文献   
952.
采用共沉淀水热合成和离子交换的方法,制备了钛与铜离子共掺杂的羟基磷灰石(Ca10(PO4)6(OH)2:HAP)(HAPTiCu),以大肠杆菌为目标物,研究了不同材料负载的多孔镍网薄膜在弱紫外光下的杀菌活性.结果表明,HAPTiCu在弱紫外光下具有高效杀菌效率,并远远高于HAPTi和P25TiO2薄膜.这主要是铜离子的抗菌与光催化分解细菌的协同作用的结果.电子自旋共振(ESR)研究表明杀菌反应的主要活性物种是O-2·.HAPTiCu薄膜释放的铜离子在光催化杀菌反应过程中,被光催化还原沉积在表面,导致了较低的铜离子溶出,从而保证了材料的稳定性.  相似文献   
953.
煤矿井下作业场所粉尘浓度的法律管理   总被引:2,自引:0,他引:2  
煤矿井下作业场所粉尘浓度管理标准的变动,会给煤矿的防尘工作带来很大影响。煤矿防尘工作的好坏主要取决于综合防尘措施的落实、防尘科技的发展状况以及与此相适应的法规标准。脱离实际的防尘标准,只能导致实际工作中的虚夸与浮躁,不利于防尘工作的正常开展  相似文献   
954.
人工神经网络在沿海区域环境复杂系统预测中的应用   总被引:6,自引:0,他引:6  
针对复杂系统的非线性特征,分析了应用人工神经网络技术实现可持续发展复杂系统预测的可能性,并以上海市和崇明县为例建立沿海区域预测模型,取得了较好的预测结果,为可持续发展复杂系统的预测研究探索了一种新的可能方法。  相似文献   
955.
Acetone,which is volatile,flammable,toxic,expen- sive and causing serious air pollution,is often used as extracting solvent in the production of powdery soy phospholipid.Recycling and reusing acetone is the key of reducing the cost of production. Therefore,saving energy and reducing emission when recycling acetone are the most important technologies during the production of phospholipid.On the basis of the productivity of powdery phospholipid being 2.4 t every day,43.2 t acetone is reused every 8 h and t...  相似文献   
956.
为探讨内源性二氧化硫(SO2)对动脉血压的影响及其信号转导通路,采用大鼠颈动、静脉插管技术研究SO2对动脉压调节作用,通过离体血管环灌流试验观察SO2对NE引起的主动脉血管环收缩作用的影响,用生物化学方法与实时定量RT-PCR技术研究SO2对离体血管一氧化氮(NO)生成、一氧化氮合酶(NOS)活性和基因表达的调节作用....  相似文献   
957.
Photoreaction of particle-bound 1-nitropyrehe (1-NP) under simulated atmospheric condition has been studied. When 1-NP coated on the surface of silica gel was suspended in a stream of nitrogen, oxygen or air, respectively, and exposed to intensive light of xenon lamp, photochemical reaction took place. The result of kinetic study showed it to be of the second order. The photoreaction products were identified by off-line HPLC/MS as 1,6-pyrenequinone, 1,8-pyrenequinone, trinitro-hydroxypyrene, dinitrohydroxypyrene, 6,6'- dipyrenenone, etc. The mutagenicity of photochemical reaction products is higher in oxygen and air, and lower in nitrogen than that of the precursor 1-NP, as detected by the Ames Bioassay.  相似文献   
958.
China is going through a rapid development stage of industrialization and urbanization.Although tremendous achievements have been made in the aspects of energy conservation,improvement of energy effectiveness and development of new and renewable energies,because of the rapid development of economy,it is difficult to change the huge total amount and fast increase of CO2 emission in the near future.China has to confront the tough challenge to address global climate change.China plans to reduce carbon intensity,that is,CO2 emissions per unit GDP,by 40 to 45% by 2020 compared with the 2005 level.It is a strategic option to coordinate domestic sustainable development with coping with global climate change on the basis of China’s national circumstances,representing the core content and key measures for transforming development pattern and realizing low-carbon development.To achieve the target,more capital and technology inputs are required for energy conservation and low-carbon development during the twelfth and Thirteenth Five Year Plan period than in the Eleventh Five Year Plan period.In addition,energy conservation achieved by structural adjustment,industrial upgrading and product value-added improvement is also expected to play a greater role.Therefore,China should strengthen technological innovation,make greater efforts to transform the development pattern,take advantage of the synergistic effect of policies and measures while coping with global climate change and building a domestic tow-oriented society.China should also establish an industrial system characterized by low-carbon emission.Then China will ultimately achieve a win-win situation in both domestic sustainable development and coping with global climate change.  相似文献   
959.
The fundamental way of satisfying the basic needs of human development is to secure the basic needs,limit luxurious and wasteful emissions,and ensure the fulfillment of climate targets,so as to achieve intra-and intergenerational equity.In this paper,the author discusses and analyzes a series of challenges that the development has to face,such as poverty elimination,urbanization,and industrialization,and the problems of increased consumption that is brought about by the improvement of living standards;the author distinguishes the stock emission,which does not need annual updating,and the flow emission of regular consumption;the author also defines the standards of energy consumption and carbon emissions that can meet the basic needs.On this basis,the author proposes the concept and method of carbon budget,compares this method with other means,and in particular,studies and analyzes the implications of international equity and sustainability of carbon budget as part of the international climate regime design.  相似文献   
960.
Climate change has become a hot topic in international environmental negotiations.For post-Kyoto international climate regime negotiations,many countries have proposed a variety of frameworks to share the emission reduction responsibilities and allocate carbon emission rights,and have tried to quantify the emission reduction obligations of all countries based on the perspectives of international equity and individual equity.In this paper,the authors have distinguished the concepts of carbon emissions rights based on these two perspectives respectively,have analyzed the relationship between carbon emissions per capita and economic development,and have calculated and compared the proportion of cumulative emissions per capita of different countries in history and future,and then authors conclude that emission reduction obligations should be allocated based on each country’s conditions,including historical emissions,development stage,and future demands.Developed countries should take the initiative to significantly reduce their emissions because they have already accomplished their industrialization process.However,developing countries are still in the process of industrialization,which requires more emission rights to meet their development needs.For China,the concept of carbon emissions based on individual equity can be used as a theoretical tool for the allocating the international carbon emissions rights.  相似文献   
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