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361.
Environmental Science and Pollution Research - Airborne emissions from concentrated animal feeding operations (CAFOs) have the potential to pose a risk to human health and the environment. Here, we...  相似文献   
362.
不同的林业补贴产生不同的效果:可能提高社会福利,也可能降低社会福利。出现这种差别的原因是补贴使林业生产收益流发生了变化,从而使得林业生产收益最大净现值到来的时间相对于社会最优时间提前或延后。论文建立了一个以林木吸收碳来衡量森林生态效益的林业生产收益定量模型,并通过该模型对华东某市的一项林场补贴政策进行分析。分析结果是,在没有补贴的情况下,该林场最优砍伐时间为第19年,当存在补贴的情况下,林场的最优砍伐时间提前到第11年,而随着碳价格从0增加至1000元/t,社会最优砍伐时间从第19年增加到第31年,造成的社会净损失从7750元/hm2增加到17704元/hm2。鉴于此,合理的林业补贴要能够促使私人效益与社会效益相统一。  相似文献   
363.
Environmental Science and Pollution Research - Capacity development has been regarded as one of many measures to empower the abilities of nations to adapt to a changing climate. Promoting public...  相似文献   
364.
This article reports a novel way to synthesize carbon nanotubes and Cu/ZnO nanoparticles using metal hyperaccumulator plants. Metal hyperaccumulator plants are traditionally used for phytoremediation to clean soil polluted by toxic metals. However, the transfer of toxic metals in plant shoots and leaves is an environmental issue because animals and other living organisms feeding on plants will transfer the metals to the ecosystem. Therefore, we suggest that hyperaccumulator plants could be used to synthesize nanoparticles. Here, Brassica juncea L., a Cu-hyperaccumulator plant, was collected around a copper mine and used as a raw chemical to produce carbon nanotubes and Cu/ZnO nanoparticles. The chlorophyll in shoots of B. juncea plants was ethanol extracted to yield chlorophyllin. Cu and Zn were extracted by HNO3 to form Cu/Zn(NO3)2. The chlorophyllin reacted with Cu/Zn(NO3)2 to form Cu/Zn chlorophyllin. Cu/ZnO nanoparticles were synthesized by direct precipitation of Cu/Zn chlorophyllin with NaOH and ethanol. The vascular bundles in B. juncea plants, which have been purified and carbonized by HNO3, were rapidly heated to about 400°C and then they were cooled to room temperature to obtain carbon nanotubes. Results indicate that the outer diameter of carbon nanotubes was around 80 nm. Cu/ZnO nanoparticles have a Cu0.05Zn0.95O composition, and had a diameter of about 97 nm. Our study not only inspires the search for a new strategy on the synthesis of nanostructure from renewable natural products, but also breaks through the traditional and limited ideas about the reuse of metals by hyperaccumulator plants.  相似文献   
365.
以2006~2010年黑龙江省噪声监测结果为依据,进行现状和变化趋势分析,找出存在问题,提出污染防治对策和建议。  相似文献   
366.
Abstract

Southeast China is one of the severe soil degradation areas in China. This paper theoretically examines the impact of some important institutional arrangements and policies, like land management pattern, the rural off-farm employment, land property change and changes in prices of agricultural products, on soil degradation in this area. It further conducts some case studies to confirm the potential relationship between the institutions & policies and soil degradation, applying the surveyed and the second hand data. The paper at last makes some conclusions and proposes some suggestions on how to promote soil conservation by improving the ways of policy decision-making and the effects of policies on land use.  相似文献   
367.
Oxidation of sulfite and competitive absorption existed in Na2SO3 solution for simultaneous removal of NOx and SO2, inhibited the long-term high-efficiency when used for practical applications. A matching strategy was developed to solve these problems. Antioxidants combination was used to retard the oxidation of antioxidant and enhance inhibition of S(IV)(tetravalent sulfur) oxidation. Hydroquinone(HQ) and sodium thiosulfate(ST) showed a positive syner...  相似文献   
368.
Abstract

The objective of social development is to construct a harmonious society. In China, the key to a harmonious society is the happiness of more than 900 million farmers living in the rural areas. This study aimed to measure rural residents’ subjective well-being (SWB) through the day reconstruction method, as well as to analyze SWB’s influencing factors through a variety of statistical methods. The results showed that the average U index was 12.79%, indicating that respondents were unhappy 12.79% of the time. Twenty-seven percent of the population had a U index greater than 0, with the average value being 47%, indicating that these people were unhappy 47% of the time. The study also found that SWB varied according to the characteristics of the respondents. Logistic regression analysis showed that social and demographic factors, including age, education, county, household size, generation number, per capita income, migration status and social networking, which significantly affected rural residents’ SWB. The size of the impact varied with the different factors.  相似文献   
369.
Environmental Science and Pollution Research - Flexible strategy of carbon tax is an important chip for the government to promote the implementation of carbon emission reduction. However,...  相似文献   
370.
根据大修安全管理的特点,提出了搞好大修安全管理应遵循的基本原则,并用科学观点进行了详细论述。  相似文献   
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