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1.
The degree of technological change biased to the environmental factor is crucial to industrial sustainable development. Using the stochastic frontier analysis method based on the translog production function and the panel data of 32 industrial sub-sectors in Shanghai over 1994–2011, this paper combines the evolution dynamic of the frontier technological structure with the evolution dynamic of technological change direction to estimate the output elasticities of production factors and the growth rate of green total factor productivity. Also, we investigate and compare the degrees of technological change biased to four production factors, i.e., capital, labor, energy, and carbon emissions. The results show that the industrial green total factor productivity in Shanghai presents an overall upward trend and mainly depends on the technical efficiency change. The improvements of labor productivity, R&D intensity, and energy efficiency can effectively enhance the green technical efficiency, while capital deepening has a mitigation effect on the green technical efficiency. The technological change of Shanghai's industrial production biases to energy use and capital saving, causing a high energy demand of industrial development. Under the dual impacts of economic development and energy-saving and emission-reduction policies, the degree of technological change biased to the environmental factor (carbon emissions) displays strong and weak alternations, indicating that the green bias of industrial technological change in Shanghai is not stable and that the green transformation of industrial development model needs to be further advanced.  相似文献   
2.
China's high‐speed economic development and reliance on overconsumption of natural resources have led to serious environmental pollution. Environmental taxation is seen as an effective economic tool to help mitigate air pollution. In order to assess the effects of different scenarios of environmental taxation policies, we propose a frontier‐based environmentally extended input–output optimization model with explicit emission abatement sectors to reflect the inputs and benefits of abatement. Frontier analysis ensures policy scenarios are assessed under the same technical efficiency benchmark, while input–output analysis depicts the wide range of economic transactions among sectors of an economy. Four scenarios are considered in this study, which are increasing specific tax rates of SO2, NOx, and soot and dust separately and increasing all three tax rates simultaneously. Our estimation results show that: raising tax rates of SO2, NOx, and soot and dust simultaneously would have the highest emission reduction effects, with the SO2 tax rate making the greatest contribution to emission reduction. Raising the soot and dust tax rate is the most environmentally friendly strategy due to its highest abatement to welfare through avoided health costs. The combination of frontier analysis and input–output analysis provides policy makers a comprehensive and sectoral approach to assess costs and benefits of environmental taxation.  相似文献   
3.
Western ideologies of imperialism conceptualise time as heterogeneous in that they assume that colonised lands are outside of historical time. In this respect, the discursive construction of an empty frontier has been crucial to colonial dispossession. Yet colonial discourses become dominant through their circulation, and so the savage spaces they imagine take on a life of their own when they are revoiced. Papuan Times, a newspaper published by graduates of an industrial mission school at Kwato Island in the colonial Territory of Papua and New Guinea after the Second World War, produces subaltern agency in its reports on the pacification of the Highlands. While its news articles reproduce the heterogeneous chronotope of colonial discourse, articles describing the missionary work of former Kwato students in the Highlands reimagine the Highlands frontier as a horizon of social transformation. The Papuan Times strategy reflects the fact that a community's pursuit of the good exists in relation to others which constrain it, and, more generally, that an anthropology of the good is also an anthropology which recognises the fraught coexistence of a plurality of values.  相似文献   
4.
正Aims and Scope The goals of Genomics,ProteomicsBioinformatics(GPB)are to disseminate new frontiers of its focused research fields,to publish high-quality discoveries in a fast-pace,and to promote open access and prompt online publication for efficient publishing.  相似文献   
5.
基于水足迹的作物生产生态效率评价——以陕西省为例   总被引:3,自引:0,他引:3  
惠婞  陈晓楠  宋健峰 《生态学报》2021,41(8):3078-3091
传统生产函数很少考虑农业生产中自然资源的要素功能,也无法表达化肥、农药的使用对环境产生的损害。研究将绿水、蓝水和灰水足迹,分别代表降水资源、灌溉水资源和作物生产的环境影响,引入农业生产函数,采用随机前沿方法测算陕西省作物生产生态效率,并分析其影响因素。结果表明:1)1985-2018年间陕西省作物生产总水足迹呈上升趋势,作物生产单位面积用水强度不断增强。单位面积水足迹及蓝、绿、灰水占比与气候、种植结构,灌溉条件和农业污染相关。2)研究期内,陕西省作物生产生态效率以2003年为分界点呈现先降后升趋势,陕西省作物生产生态效率的U型波动对应政府对耕地资源保护和农业污染管控政策变化。3)作物生产生态效率低下的区域集中在生产落后的农业区和农业条件差的工业区,农业耕地质量差,灌溉条件匮乏,低效率(产值角度)的灌溉和化肥农药施用以及落后农业生产方式是导致作物生产生态效率低下的主要原因。4)研究期内,陕西省作物生产经历了从规模报酬递增,到规模报酬递减2个阶段,与耕地面积的变化基本对应。短期内,考虑各投入要素的产出弹性调整种植结构和化肥农药施用量是提高作物生产生态效率的有效措施,而促进农业产业升级和技术革新是推动作物生产生态效率提升的根本路径。  相似文献   
6.
Twelve new heteroleptic nickel(II) and copper(II) complexes of the type [M(L1–6)(Pfx)2] ( 1 – 12 ), where L1–6=2-benzylidenehydrazinecarbothioamide (L1), 2-benzylidene-N-methylhydrazinecarbothioamide (L2), 2-benzylidene-N-phenylhydrazinecarbothioamide (L3), 2-(4-methylbenzylidene)hydrazinecarbothioamide (L4), 2-(4-methylbenzylidene)-N-methylhydrazinecarbothioamide (L5) and 2-(4-methylbenzylidene)-N-phenylhydrazinecarbothioamide (L6), Pfx=pefloxacin and M=Ni(II) or Cu(II) have been synthesised, and their structures were confirmed by different spectral techniques. The spectral data and density functional theory (DFT) calculations supported the bonding of pefloxacin drug molecule via one of the carboxylate oxygen atoms and the pyridone oxygen atom, and the thiosemicarbazone ligand via the imine nitrogen and the thione sulfur atoms with the metal(II) ion, forming distorted octahedral geometry. In vitro antiproliferative activity of the synthesized complexes was evaluated against three human breast cancer (T47D, estrogen negative (MDA-MB-231) and estrogen positive (MCF-7)) as well as non-tumorigenic human breast epithelial (MCF-10a) cell lines, which showed the higher activity for the copper(II) complexes. The interaction of the synthesized complexes with an oncogenic protein H-ras (121 p) was explored by in silico molecular docking studies. Further, in silico pharmacokinetics and ADMET parameters were also analysed to predict the drug-likeness as well as non-toxic and non-carcinogenic behavior, and safe oral administration of the complexes.  相似文献   
7.
Stork  Nigel E. 《Plant Ecology》2001,153(1-2):313-317
So little is known about about what goes on above our heads in rain forests and what lives there that the rain forest canopy has been called the last biological frontier. Until very recently, researchers had very limited access to the canopy, even in temperate forests and, not surprisingly, we are only just beginning to discover this part of the world. A new breed of scientists, canopy biologists, has evolved and have accelerated the rate of discovery. The implications for management of forests of this new voyage of discovery are enormous. At present conservationists, forest managers, environmental policy makers, and other research users have not even started to consider how to integrate the resulting new information for future planning and sustainable management and use of forests.The Earth Summit in 1992 drew attention to several of the principal biological dilemmas of the 20th century: biodiversity and forest loss, land conversion, climate change and ozone depletion. Understanding the importance of forest canopies for these issues is essential and researchers need to consider how better to coordinate their activities and deliver their results if they are to influence decision making at all levels. One new initiative shows some promise in this regard. Recently the United Nations Environment Program has supported the International Canopy Crane Network. This network of crane sites around the world will focus on providing an improved scientific basis for the importance of the forest canopy with respect to the Conventions on Biological Diversity, Climate Change and Ozone Depletion.  相似文献   
8.
刘泽隆  范红霞 《生物学杂志》2007,24(1):55-58,43
综述了前沿模型的产生、发展、分类,并在此基础上根据2004年度中国主要生物科技上市公司样本数据,尝试构建中国生物科技企业前沿模型。分别选用了随机前沿模型、确定性参数前沿模型和确定性统计前沿模型并根据主要统计检验指标进行分析比较,结果发现:2004年度中国主要生物科技企业上市公司样本数据适合于建立确定性统计前沿模型。根据建立的确定性统计前沿模型测定中国主要生物科技企业上市公司技术效果发现:中国主要生科企业普遍存在着技术效率低下、差距大的现状;资本投入对产出的影响大大高于劳动力投入对产出的影响;中国东、中、西部主要生科企业总平均技术效率并无显著差异。  相似文献   
9.
American fishery policy is imprisoned by mental models that defeat coherence concerning the formulation of promising management futures. The idea of the frontier is at the core of current policy incoherence. Images—and specious accounts—of: (1) unowned fish; (2) IFQs/ITQs as property rights; (3) private ownership as necessary and sufficient for individuals (called owners) to suddenly become far-sighted stewards of nature; and (4) rights-based fisheries combine to defeat innovative thought about how to extricate ourselves from deep conceptual confusion. Until we purge the frontier—with its associated images—from our mind it will be difficult to undertake ecosystem management. More seriously, it will be impossible to rectify existing governance and management arrangements that are responsible for the degraded state of America’s fisheries.  相似文献   
10.
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