绿色金融发展与产业结构优化升级研究 —基于江西省的实证

近年来,随着绿色金融体系建设上升为国家战略,我国绿色金融发展取得了不少 令人瞩目的成果。在我国经济发展进入新常态和大力倡导供给侧结构性改革的时代背景下,江 西省作为首批建设绿色金融改革创新试验区,研究江西省绿色金融发展促进产业结构调整升 级对加快生态文明体制改革和建设美丽中国具有重要的现实意义。在分析绿色促进产业结构 调整升级的机制之后,通过构建灰色关联模型对江西省2008~2016年绿色金融与产业结构关联 度进行实证分析。最后,结合江西省绿色金融发展的实际情况,提出了相应的对策建议以促进 江西省产业结构调整升级。     

食品中内源性甲醛的产生机理及控制技术

甲醛属于致癌、致畸物质,添加到食品中会对食用此食品的人造成伤害。本文综述内源性甲醛在各类食品中的来源、形成机理、影响因素及其毒性控制技术。以期在食品安全生产过程中,更好地减少和控制各类食品中内源性甲醛的含量。     

The Distributional and Allocative Impacts of Virtual Labor Mobility across Time Zones through Communication Networks

Using a specific‐factors' model, with two goods (a shift‐working good and a non‐shift‐working good), three factors (capital specific to shift‐working, land specific to non‐shift‐working and labor) and two countries (Home and Foreign), which are located in different time zones, we highlight the impact of trade in labor services via communication networks on factor prices and production patterns. If two countries are identical in size, then under free trade in labor services, all workers work only in their local daytime, and night shift in each country is performed by imported labor services supplied by residents of the other country in their local daytime. Night‐time wage becomes the same as daytime wage (a wage equalization result). Other factor prices are also equalized. In both countries, capital rental rate increases, while land rent decreases. However, if two countries are different in size, trade in labor services does not equalize wages: in the large country, wages for night‐shift workers are higher than daytime wages and some residents work at night; in the small country, daytime wages become higher than night‐time wages and no one works at night, and night‐shift work is done by imported labor services from the large country. Land rent in the small country decreases. Land rent in the large country may or may not decrease, but it is always higher than in the small country. Capital rental rates in both countries are equalized and increase.     

Contradictions of the Climate-Friendly City: New Perspectives on Eco-Gentrification and Housing Justice

As local governments and corporations promote ‘climate friendliness’, and a low-carbon lifestyle becomes increasingly desirable, more middle- and upper-income urban residents are choosing to live near public transit, on bike- and pedestrian-friendly streets, and in higher-density mixed-use areas. This rejection of classical forms of suburbanization has, in part, increased property values in neighborhoods offering these amenities, displacing lower-income, often non-white, residents. Increased prevalence of creative and technology workers appears to accelerate this trend. We argue that a significant and understudied socio-environmental contradiction also occurs where the actual environmental outcomes of neighborhood transformation may not be what we expect. New research on greenhouse gas emissions shows that more affluent residents have much larger carbon footprints because of their consumption, even when reductions in transportation or building energy emissions are included. We describe an area in Seattle, Washington, the location of Amazon's headquarters, experiencing this contradiction and show a distinct convergence of city investments in low-carbon infrastructure, significant rises in housing prices and decreases in lower-income and non-white residents. We conclude with a discussion of a range of issues that require more attention by scholars interested in housing justice and/or urban sustainability.     

如何理解逻辑与历史相一致原则? ——对近期学术界相关争鸣的反思

将逻辑与历史相一致原则视为马克思主义经济学的重要方法论,发端于恩格斯.这一原则的原初语境仅指马克思的叙述方法,与研究方法无关.马克思是按照特定社会内部结构来安排范畴出现的顺序,这一逻辑顺序与范畴的历史顺序无关.聚焦于逻辑与历史是否一致,不仅遮掩了这种叙述方法的光芒,也造成了对作为《资本论》逻辑起点的商品范畴和价值规律等重要问题的误解.学术界不应该通过逻辑与历史辩证统一等表述来进行辩护,而应该对逻辑与历史相一致原则进行彻底清算,还原马克思主义经济学叙述和建构原则的真相.     

Estimating the gravity model when zero trade flows are frequent and economically determined

ABSTRACT

Since the 1950s, we have known that the presence of zero-valued dependent variables can seriously bias econometric estimates whether the zeros are included or excluded. Yet the widely-used gravity model is frequently estimated on samples that include large fractions of zeros. An influential paper by Santos Silva and Tenreyro – based on simulations that include no economically-determined zeros – concludes that the bias problems resulting from zeros and those resulting from heteroscedasticity and nonlinearity can be solved using the Poisson Pseudo-Maximum-Likelihood (PPML) model including the zero values. This paper begins by adapting the Santos Silva and Tenreyro experimental design to include economically-determined zeros to see whether this conclusion continues to hold. With this design, it finds that alternative estimators have lower bias than PPML. Changing to a Monte Carlo design that replicates the much-higher real-world frequency of predicted values near zero restores the finding of lower bias with the PPML estimator. The results highlight the need for very careful design of Monte Carlo experiments when evaluating alternative estimators of the gravity model.     

Can interfirm trust improve firms' cooperation on environmental innovation? The moderating role of environmental hostility

Based on the logic of “trust‐behavior,” we examined the relationship between interfirm cognitive trust, emotional trust, and firms' cooperation on environmental innovation, as well as the moderating role of environmental hostility on the relationship between two dimensions of interfirm trust and cooperation on environmental innovation. Data for the study were collected from 216 firms in China. The results indicated that both interfirm cognitive trust and emotional trust were positively correlated to firms' cooperation on environmental innovation, and the effect of emotional trust on firms' cooperation on environmental innovation was negatively moderated by environmental hostility. Finally, the results were discussed and future directions put forward.     

Robust Markowitz mean‐variance portfolio selection under ambiguous covariance matrix

This paper studies a robust continuous‐time Markowitz portfolio selection problem where the model uncertainty affects the covariance matrix of multiple risky assets. This problem is formulated into a min–max mean‐variance problem over a set of nondominated probability measures that is solved by a McKean–Vlasov dynamic programming approach, which allows us to characterize the solution in terms of a Bellman–Isaacs equation in the Wasserstein space of probability measures. We provide explicit solutions for the optimal robust portfolio strategies and illustrate our results in the case of uncertain volatilities and ambiguous correlation between two risky assets. We then derive the robust efficient frontier in closed form, and obtain a lower bound for the Sharpe ratio of any robust efficient portfolio strategy. Finally, we compare the performance of Sharpe ratios for a robust investor and for an investor with a misspecified model.     

关于公路与桥梁之间过渡段施工技术初探

本文主要分析了公路桥梁间过渡段出现不均沉降的原因以及公路桥梁间过渡段的施工技术的应用情况,此项技术对降低施工成本,提升桥梁的可靠性与安全性有重要作用。     

改进的沾滴法测量缓蚀剂预膜厚度

分析了传统沾滴法测量预膜厚度存在的问题,对原有的方法进行了改进,使用自制实验装置采用改进后的沾滴评价法测试分析了不同材质、不同管径管件的平均预膜厚度。结果表明,不同材质的管材表面吸附能力不同,导致管件平均预膜厚度相差较大,其中铜管的平均预膜厚度最大(0.05mm左右),碳钢管的平均预膜厚度最小(0.013mm左右);而管径对管件平均预膜厚度的影响很小。实验所得结果与同位素示踪法测定膜厚结果较吻合,从而说明改进后的沾滴评价法是一种室内评价管件平均预膜厚度的有效方法。