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101.
Helmut Baltruschat Prof. Dr. 《Chemphyschem》2009,10(8):1311-1313
Electrochemistry down to the molecular level was the main theme of the 59th annual meeting of the International Society of Electrochemistry (ISE, see logo). Around 1400 scientists from all over the world met in Seville to discuss modern aspects, progress in methods and new mechanistic insights.
102.
2018年实施的《环境保护税法》确立了排污征税的法律依据。环境保护税会增加成本并沿着供应链向下游逐级转移,从而改变社会分配格局。对此,基于供应链视角研究环境保护税的社会分配效应:首先,分析环境保护税沿着供应链的逐级转移,发现环境保护税会同时减少企业利润和消费者剩余;其次,比较企业利润和消费者剩余的减少程度,发现环境保护税会提高消费者的社会分配地位,也会提高零售企业的社会分配地位,但是会降低制造企业的社会分配地位;最后,比较环境保护税减少的企业利润和消费者剩余与形成的税收收入之间的相对大小,发现环境保护税会导致净社会福利损失,而且税负分担非常不均衡,制造企业承担最多,零售企业次之,消费者最少。 相似文献
103.
David González-Sánchez Onésimo Hernández-Lerma 《Journal of Difference Equations and Applications》2013,19(1):39-53
In this paper, we study an inverse optimal problem in discrete-time stochastic control. We give necessary and sufficient conditions for a solution to a system of stochastic difference equations to be the solution of a certain optimal control problem. Our results extend to the stochastic case the work of Dechert. In particular, we present a stochastic version of an important principle in welfare economics. 相似文献
104.
Paola A. Mello Juliana S.F. Pereira Marcia F. Mesko Juliano S. Barin Erico M.M. Flores 《Analytica chimica acta》2012
In this review sample preparation strategies used for crude oil digestion in last ten years are discussed focusing on further metals and non-metals determination. One of the main challenges of proposed methods has been to overcome the difficulty to bring crude oil samples into solution, which should be compatible with analytical techniques used for element determination. On this aspect, this review summarizes the sample preparation methods for metals and non metals determination in crude oil including those based on wet digestion, combustion, emulsification, extraction, sample dilution with organic solvents, among others. Conventional methods related to wet digestion with concentrated acids or combustion are also covered, with special emphasis to closed systems. Trends in sample digestion, such as microwave-assisted digestion using diluted acids combined with high-efficiency decomposition systems are discussed. On the other hand, strategies based on sample dilution in organic solvents and procedures recommended for speciation analysis are reported as well as the use of direct analysis in view of the recent importance for crude oil field. A compilation concerning sample preparation for crude oil provided by official methods as well as certified reference materials available for accuracy evaluation is also presented and discussed. 相似文献
105.
TADAYOSHI MASUDA JOHN F. YANAGIDA JAMES E. T. MONCUR SAMIR A. EL‐SWAIFY 《Natural Resource Modeling》2010,23(1):22-47
Abstract In this paper, we develop a land use allocation model to search for the optimal ratio of organic (nonchemical) and conventional (chemical‐use) farming acreage. The idea is to incorporate stochastic production frontiers (SPFs) to a multi‐criteria decision making (MCDM) model as technological constraints. The objectives of this model are to maximize net returns, minimize chemical inputs, and optimize organic inputs given environmental and ecological concerns. The compromise solutions suggest the desirable ratio of organic and conventional farming acreage and targetable operations for each farming system to improve regional welfare. This method was applied to the Kona coffee belt, Hawaii, and the analysis determined the optimal proportion of organic and conventional Kona coffee farming fields as 0.265 to 0.735 in terms of optimizing community benefits or regional welfare. 相似文献
106.
Wulf Gaertner 《Mathematical Social Sciences》1983,4(2):137-154
We propose that transformations of the well-known broad Borda method are employed as aggregation mechanisms for profiles of so-called individual extended orderings. We define the class of transformed positional broad Borda rules TPBB and introduce considerations of equity, inequity, and a third concept which is somewhat intermediate in character. It is shown that all elements of class TPBB satisfy the strong Pareto principle, strong monotonicity. Suppes indifference axiom, and a weak independence condition called positionalist independence. In an appendix, several examples are presented that demonstrate the performance of some of the aggregation rules proposed in the paper. 相似文献
107.
Peter J. Lambert 《Mathematical Social Sciences》1985,9(1):19-26
The question of conflict between the rankings of income distributions with the same mean by the Gini coefficient and by individualistic social welfare functions is re-examined. The negative result of Newbery (1970) is extended. However, positive results are obtainable which reverse Newbery's conclusion by admitting into the individual's utility index a measure of his position in the income distribution, or of his deprivation with respect to others' incomes. 相似文献
108.
the period o 《广州化学》2007,(1)
teacher education in different period,then analyze the reason of the "charging" policy of the teacher education,and unscramble the policy of "the education of the normal school student is free" that issued newly.higher teacher education;tuition policy;normal school student0煤炭高等教育Meitan Higher Educati 相似文献
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