毛竹水溶性多糖提取工艺的优化及结构表征

采用响应面法优化毛竹水溶性多糖的提取工艺,分析其成分,并进行结构表征。研究结果表明,优化的毛竹多糖(BSP)提取条件为:料液比1∶27(g/mL)、提取温度78 ℃、提取时间4 h,该条件下BSP提取率为(5.18±0.07)%,提取物中多糖含量为(72.14±0.02)%,糖醛酸含量为(9.76±0.03)%;BSP具有酸性多糖典型的官能团特征吸收峰,其单糖组成及摩尔比为n_甘露糖∶n_葡萄糖∶n_阿拉伯糖∶n_木糖∶n_鼠李糖∶n_半乳糖=62.52∶23.05∶10.35∶2.78∶0.79∶0.51;BSP由两个主峰组成,相对分子质量分别为91.11、4.55 kDa。BSP是一种混合酸性多糖。     

Do environmental regulations hamper small enterprises' market entry? Evidence from China

Due to the serious increase of environmental pollution in China, environmental regulations have become significantly stringent. Such regulations are playing an increasingly important role in the development of small enterprises (SEs) in China, especially in SEs' market entry. However, existing studies pay little attention to this issue. This paper investigates for the first time the effect of environmental regulations on SEs' market entry and the mechanism of environmental regulation effects in China. We consider two sets of panel data for the periods 2003–2010 and 2012–2015 in China. We also use the fixed effect model and the instrumental variable method to explore the role of environmental regulations in SEs' market entry. The results show that, overall, environmental regulations play a significantly positive and robust role in SEs' market entry. However, the mechanisms associated with the effect of environmental regulations on different innovative types of SEs differ. Environmental regulations promote the market entry of SEs with product innovation, but this impact is not significant for SEs with research and development (R&D) activities and R&D institutions. Our findings indicate that China's SEs prefer product innovation, which is a lower level innovative type, over R&D innovation, as a means to avoid the negative impact of stringent environmental regulations.     

The ABC mechanism: an incentive compatible payoff mechanism for elicitation of outcome and probability transformations

When it comes to experiments with multiple-round decisions under risk, the current payoff mechanisms are incentive compatible with either outcome weighting theories or probability weighting theories, but not both. In this paper, I introduce a new payoff mechanism, the Accumulative Best Choice (“ABC”) mechanism that is incentive compatible for all rational risk preferences. I also identify three necessary and sufficient conditions for a payoff mechanism to be incentive compatible for all models of decision under risk with complete and transitive preferences. I show that ABC is the unique incentive compatible mechanism for rational risk preferences in a multiple-task setting. In addition, I test empirical validity of the ABC mechanism in the lab. The results from both a choice pattern experiment and a preference (structural) estimation experiment show that individual choices under the ABC mechanism are statistically not different from those observed with the one-round task experimental design. The ABC mechanism supports unbiased elicitation of both outcome and probability transformations as well as testing alternative decision models that do or do not include the independence axiom.

     

National response strategies and marketing innovations during the COVID-19 pandemic

During the COVID-19 pandemic, different nations have adopted a variety of response strategies to fight and contain the new coronavirus. Such national response strategies can be classified into three categories based on their underlying philosophy: strict control with unlimited resources, relentless contribution with limited resources, and rough rationality with limited resources. We discuss the philosophies, characteristics, and performances of the three response strategies and when they should be adopted. We also examine what marketing innovation strategies enterprises should adopt to survive and grow their businesses in both the short and long term. This study provides important strategic implications for national policymakers and enterprises on the use of response strategies as well as marketing innovation tactics and strategies to be used both during and after the pandemic.     

川西北高原藏区农村贫困化分异机制探测

[目的]客观揭示农村贫困化地域分异机制,为科学推进川西北高原藏区精准扶贫创新途径、综合战略和认真贯彻落实中央治藏方略提供参考依据。[方法]应用地理探测器模型、GIS空间分析与地统计方法等方法,探测川西北高原藏区贫困村单位面积GDP分异的主导因素,揭示农村贫困化分异机制,提出不同贫困化地域类型的扶贫政策措施。[结果]影响川西北高原藏区农村贫困化分异的主导因素包括到主要交通道路距离、归一化植被指数(NDVI)、土地利用、年均温度和海拔高程等,各因素对贫困村经济发展分异的解释力分别为80. 76%、12. 82%、8. 82%、5. 45%和3. 96%;贫困村经济发展贫困化的分异机制存在明显差异,可归纳为交通区位约束型、自然环境约束型和经济区位约束型等三大类型;农村贫困化驱动机制下的贫困村精准扶贫政策措施亟需因地制宜、科学推进、讲求实效,有序推进精准扶贫战略。[结论]精准扶贫应分类指导、重点突破,尤其加强贫困村交通、水利、公共基础设施建设和特色农牧业产业培植,注重多种扶贫模式的综合集成。     

环境公平感知、社会信任与农户低碳生产行为*——以农膜、秸秆处理为例

［目的］研究旨在探讨环境公平感知和社会信任与农户低碳生产行为之间的关系，为促进农户生产行为向低碳化方向转变提供对策建议。［方法］基于陕西和甘肃两省的村域调查数据，以农膜和秸秆处理为例，运用二元logistic模型探讨环境公平感知和社会信任对农户低碳生产行为的影响，并结合分层回归分析了社会信任在环境公平感知和农户低碳生产行为间的调节效应。［结果］（1）在环境公平感知维度中，人际公平感知正向影响农户的农膜和秸秆处理行为； （2）对社会信任来讲，人际信任对农户农膜和秸秆处理行为均有显著的促进作用，而制度信任仅对农户秸秆处理行为具有正向影响； （3）人际信任在种际公平感知和农户农膜处理行为之间具有显著的正向调节效应，而制度信任在两者之间具有显著的负向调节效应； 同样，人际信任在人际公平感知和农户秸秆处理行为之间具有正向调节效应，而制度信任弱化了人际公平感知对农户秸秆处理行为的影响。［结论］环境公平感知和社会信任是影响农户低碳生产行为的关键因素，且社会信任在种际公平感知和农户农膜处理行为之间以及在人际公平感知和农户秸秆处理行为之间具有显著的调节作用。     

军民融合协同创新驱动产业园区高质量发展研究

军民融合产业园区高质量发展对于推进军民深度融合、在全国形成可复制可推广经验具有重要意义。军民融合协同创新通过促进新知识涌现、推进新产业集聚发展，最终汇聚经济发展新动能，驱动园区高质量发展。在提出军民融合协同创新驱动园区高质量发展的机理与组织框架基础上，将发展模式归纳为以分享经济为背景的资源共享模式、以新型研发机构为核心的第三方模式、以产业联盟为核心的产业链拓展模式和以交易平台为核心的“PPP”模式，最后提出相关对策建议。     

健全我国企业环保信用评价法律制度的正当性面向

《环境保护法》等环境法律体系日渐趋同的多元共治理念，渗透并引发环境法律制度体系的结构性转型；国内环境信息公开制度保障公众环境知情权的核心功能不能容纳企业环保信用评价制度的制度功能；信用制度与信息制度错序产生的国内外法治及社会环境迥异等，决定了我国企业环保信用评价制度健全的正当性面向。     

Factor Heterogeneity,Factor Market Imperfection and Trade

This paper develops a tractable model of examining how factor heterogeneity and imperfect factor market interact for determining a pattern of trade. Institution plays a crucial role for the interaction. In my work, firm productivity is defined as a composition of factor productivity and technology. Thus, input selection should affect the pattern of Melitz’s intra-industry allocation due to the incurring transaction cost. For a simple model, I assume two factors (labor and capital) and two sectors, which are relatively less institution-dependent and relatively more institution-dependent. When the economy is open, effect of the transaction cost on income distribution is more drastic for an institutionally underdeveloped country. Depending on institutional quality, the economic openness reallocates resource across countries through job creation or job destruction. The job turnovers redistribute income between heterogeneous labors within countries. The income redistribution is catalyzed by international mobility of capital. As a result, income disparity is widened between the institutionally developed country and the institutionally underdeveloped country. This paper can contribute to the literature of institution and international trade.     

河南省传统村落空间分布特征及影响因素研究

[目的]分析河南省传统村落的空间分布特征及其影响因素,以期为中原地区传统村落的建设发展提供指导。[方法]文章通过谷歌地理信息系统及Arc GIS10. 2软件对河南省124个国家级传统村落的空间分布类型、分布格局、分布均衡型及影响因素进行分析,采用最邻近距离法、核密度估计法及地理集中程度等方法揭示其空间分布特征及其形成的影响因素。[结果]最邻近距离法分析R=0. 628,小于1,分布类型为凝聚型。核密度分析中,整体空间分布呈现3个核心区域,平顶山东北区域,豫西北沿省边界呈带状分布及豫南信阳南部,空间分布受地理、经济和文化等因素影响。[结论]河南省传统村落的空间分布属凝聚型不均衡分布。从地级市层面上分析,主要集中在平顶山东部、信阳南部和三门峡地区;从分区层面上,以豫中较多,豫北、豫西和豫南其次,豫东基本空白。形成原因与地理高程、社会经济和历史事件有关。交通不便、经济相对发达或相对落后、历史事件少发的区域,传统村落保存较为完整。