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31.
Illegal logging has attracted worldwide attention, and some measures, such as timber procurement policies and timber regulations, have been taken. However, there are no studies that examine the governance of illegal logging using game theory. This paper applies game theory to analyze the subsidy policy for governing illegal logging as well as the effects of the subsidy on the benefits of suppliers and operators of forest products. The results show that controlling illegal logging has an impact on exporting enterprises, and the effects produced by subsidies and non-subsidies are different for enterprise. Enterprises that receive subsidies will occupy foreign markets and gain additional profits, while enterprises that are not subsidized will exit foreign markets. The amount of subsidies is related to enterprise’s governance cost. The benefit for operators and suppliers depend on the combination of supervision level and forest products’ legality. The critical point of regulation of operators is related to regulatory costs, the additional benefits of weak supervision of suppliers, and penalties for regulatory failure. The critical point for suppliers to select legal raw materials is related to suppliers’ operating costs, gray income, and the degree of punishment. 相似文献
32.
彭絮 《农业图书情报学刊》2015,27(12):157-161
随着社会进步,网络和电子资源的迅猛发展,读者阅读行为正发生质的改变,图书馆传统服务正面临历史性危机。作为工作于流通阅览部一线的馆员,必须在反思自我的同时,紧抓社会潮流、洞悉读者习惯,基于读者外借图书规律进行研究,化被动为主动,为读者推送高质量的阅读参考信息,提高馆藏资源的利用效率。 相似文献
33.
For the capillary mats using wet construction, a winter experiment designed to investigate the heat transfer performance was described, and the heat transfer performance analysis which contains the comparisons between different pipe space and different thickness of cement mortar surface was carried out. As a result, compared with that of the traditional radiant heating pipes, the capillary mats of wet construction require supply water with lower temperature, and it shows good heat transfer performance and system energy efficiency as well. According to the demand of indoor heat dissipation and human comfort as well as the coupling relationship between the temperature of supply water and surface construction thickness, it is suggested that the proper construction method should be comprehensively considered in practical applications. 相似文献
34.
Production of high strength steel bumper can greatly enhance the occupant safety.However,it is very hard to form high strength steel plate.There is rare domestic successful reference.The hot stamping technology aboard increases costs significantly,and the efficiency is low.Therefore,the only solution is combining advanced numerical simulation technology with current adjusting stamping process.The cold forming process of a sedan’s high strength steel bumper is simulated by FEM software Dynaform and the results show that springback and crack are the main defects.A law is summed up by researching the influence of different shapes of addendums on part forming and springback.Finally,the optimized shape of addendum is obtained by adjusting the addendum and adding convex roofs.It provides references for manufacturing similar high strength steel parts. 相似文献
35.
Several SNP (single nucleotide polymorphism) genotyping methods have been developed in the past most of which require sophisticated instrumentation and large initial investments. We describe here a high-throughput SSCP (single strand conformation polymorphism) system on our HEGS (high efficiency genome scanning) platform, which is simple, accurate, cost effective and requires neither restriction digestion of the amplification products nor elaborate post-PCR processing detection. Several parameters critical to SSCP analysis were optimized viz., gel matrix and concentration, gel running temperature, buffer composition, running conditions and PCR primer design so as to identify SNPs in amplicons ranging from 100 to 750 bp in size. A simple post-PCR processing system was developed using fluorescent dye for quick and easy detection of SNP polymorphism. HEGS-SSCP was also found to be useful in uncovering simple sequence repeat differences between different genotypes that differ by one or few di/tri nucleotide repeats. The practical utility of this system is illustrated with two successful efforts towards construction of high resolution linkage maps of a lesion mimic locus on chromosome 7 and a major quantitative trait locus conditioning field blast resistance on chromosome 4 in rice. 相似文献
36.
37.
Wenting Wang Zhili Wang Wensheng Hou Li Chen Bingjun Jiang Wenya Ma Lijuan Bai Wenwen Song Cailong Xu Tianfu Han Yongjun Feng Cunxiang Wu 《作物学报(英文版)》2022,(1):273-279
Soybean(Glycine max[L.]Merr.)is a food and oil crop whose growth and yield are influenced by root and nodule development.In the present study,Gm NMHC5 was found to promote the formation of nodules in overexpressing mutants.In contrast,the number of nodules in Gmnmhc5 edited with CRISPR/Cas9 decreased sharply.In 35 S:Gm NMHC5 mutants,expression levels of genes involved in nodulation were significantly up-regulated.Both in vitro and in vivo biochemical analyses showed that Gm NMHC5 directly interacted with Gm GAI(a DELLA protein),and the content of gibberellin 3(GA3)in overexpressing mutants was lower than that in the wild type.These results revealed that Gm NMHC5 participates in the classical GA signaling pathway,and may regulate the content of GA_3 to match the optimal concentration required for nodule formation,thereby promoting nodulation by directly interacting with Gm GAI.A model illustrating the mechanism by which Gm NMHC5 promotes soybean nodulation is presented. 相似文献
38.
39.
By varying the ratios of N-(3-chloro-2-hydroxypropl) trimethylammonium chloride and orthophosphate to starch, a series of
amphoteric starch with different degree of substitution (DS) were prepared for evaluating sizing effect of amphoteric starch for cotton warps. The amphoteric starch contained quaternary
ammonium and phosphate groups simultaneously, and was set to electric neutrality by varying relative quantity of anionic and
cationic groups in order to prevent adverse effects of negative and positive charges. The influence of amphoteric modification
of starch on the adhesion to cotton fibers was assessed by measuring tensile strength and work-to-break of slightly sized
cotton roving and comparing the adhesion of amphoteric starch with those of phosphorylated one. Comparison on mechanical performances
of amphoteric starch film over phosphorylated one was evaluated in terms of tensile strength, breaking extension and wear
loss of starch film. The properties such as increase in tensile strength, loss in elasticity, abrasion resistance, and hairiness
of cotton yarns sized with amphoteric starch were evaluated through control tests by the comparison with those of phosphorylated
one. When zeta potential of amphoteric starch was set close to zero, the adhesion increased and the properties of sized yarns
enhanced as the modification level increased. The amphoteric starch was evidently superior to phosphorylated one in improving
the quality of sized cotton yarns. The amphoteric starch with neutral zeta potential and DS levels of 0.02–0.03 for quaternary ammonium groups and phosphate ones, respectively, could be applied to size cotton warp
yarns for the improvement of yarn quality. 相似文献
40.
在信息化时代的大背景下,随着煤矿和非煤矿行业的迅速发展,各级政府和安全监管部门对安全生产的重视程度越来越高。文章在对我国矿山生产企业的发展以及人才的社会需求预测分析基础上,对开设安全生产监测监控技术专业进行了必要性和可行性分析。 相似文献