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41.
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。 相似文献
42.
43.
Mehmet Bilal Ünver 《Telecommunications Policy》2019,43(2):154-170
One of the key factors for a thriving cloud computing market is the ‘interoperability’ between the relevant hardware and software that govern the cloud services. While a complete interoperability means different cloud users being able to exchange the management tools, server images and other software, this is infrequently realised because users are locked into (proprietary) cloud ecosystems. This (problem of vendor lock-in) is potentially accompanied with another problem revolving around the content delivery networks being integrated with the distinct clouds along with possible harms to media pluralism as well as interoperability. In view of these concerns, this study focuses on competition law, standardisation and regulatory policies, and elaborates on to what extent cloud interoperability needs to be secured under EU legal fora. Overall, it is found that vendor lock-in might be attended by ‘coupling’ and complex ‘layering’ strategies, whereas efficiency and/or security based justifications would arise as the counter-balancing reasons. Based on the findings, the study concludes that while focusing on the vertical (i.e., vendor lock-in) concerns, a comprehensive viewpoint needs to be upheld, allowing efficiencies (i.e., proprietary enhancements) based on the architectural design and innovations, obviating narrowly-fashioned (i.e., foreclosure-based) interventions such as in Microsoft case. It is also underlined that cloud interoperability has a content dimension that would require a broader perspective, extending to horizontal concerns and requirements within the context of EU policy making strategies. 相似文献
44.
从理论和实证两个方面探讨了产业融合对中国装备制造业创新效率的影响,以及网络中心性和网络异质性对二者关系的调节作用。基于2006—2015年省际装备制造7个子行业面板数据,采用ISCNFI指数测度模型和基于产出距离函数的超越对数前沿分析方法,分别测度装备制造业产业融合程度及创新效率变化情况,进而利用面板回归模型对理论假设进行实证检验。结果显示:产业融合程度与中国装备制造业创新效率存在倒“U”型曲线关系,即随着产业融合程度提升,中国装备制造业创新效率呈现出先上升后下降的变化趋势;网络中心性强化了产业融合对装备制造业创新效率的提升作用,而网络异质性削弱了产业融合对装备制造业创新效率的提升作用。 相似文献
45.
Recent researches have shed light on the effect of cognitive ability on economic decision-making. By measuring cognitive ability applying Raven's progressive matrix test, we obtain two significant results that this effect affects decision-making in two types of experimental ultimatum games. First, the higher the cognitive ability, the larger the amount a sender offers when the offer is smaller than or equal to the half split. Second, the higher the responders’ cognitive ability, the smaller the offer they accept, when they accept it or not with the strategy method. This study not only finds new factors that affect decision-making in experimental ultimatum games, but also provides more evidences that cognitive ability influences economic decision-making. 相似文献
46.
David Giauque Frédéric Varone 《International Journal of Human Resource Management》2019,30(5):879-901
AbstractThis study investigates whether work opportunities have an impact on stress and the related turnover intentions of employees working in intergovernmental international organizations (IOs). It contextualizes the job resources and demands model within IOs’ specific work conditions. The empirical test is based on original data from a survey administered in four major organizations of the United Nations system. Results demonstrate that social work opportunities and work–life balance are organizational levers reducing stress and willingness to quit for employees who are facing red tape or the stresses of being an expatriate. In this context, the relationships between these work opportunities and turnover intention are partially mediated by stress. Contextualized HR management propositions are made to help organizations coping with these management challenges. 相似文献
47.
《International Business Review》2019,28(2):305-315
Successful organizations have dynamic capabilities that are aligned with their competitive environments. As competitive environments globalize, the dynamic capabilities driven by managers with multicultural backgrounds are increasingly relevant. These managers are more likely to seize cognitively distant opportunities than monocultural managers. Using panel analysis of multilevel data from 355 elite football (soccer) teams, we find support for a moderated relationship among the degree of globalization in the competitive environment, the multicultural background of team managers, and team performance. When the competitive environment is highly global, teams with multicultural managers outperform teams with monocultural managers. When the competitive environment is less global, the reverse is true. The same effect holds when tested both cross-sectionally and longitudinally. 相似文献
48.
This paper offers estimations for the Portuguese path of the Non‐Observed Economy (NOE), in the period 1970–2015, through two seminal approaches: monetary method and the Multiple Indicators Multiple Causes (MIMIC) model. It is observed that the tax burden and social benefits are its main causes. Then, to get a more in‐depth understanding of the phenomenon, it provides a study of the Granger causality between the NOE and the official Gross Domestic Product (GDP), emphasizing the implications of the NOE on the Portuguese economy. Evidence has been found for the existence of bidirectional causality between the NOE and the GDP, suggesting that the formal economy affects the NOE, and conversely that the NOE affects the economic growth. 相似文献
49.
This paper investigates the impact of international sanctions on energy efficiency by employing the panel fixed effect as well as average marginal effect from the Tobit model via data on 30 sanctioned states over the period 1996–2015 with international sanctions including unilateral, plurilateral, U.S., EU, UN, economic, and non-economic cases. Overall, we find that the imposition of unilateral sanctions leads to a 0.067% decrease in energy efficiency, but that of plurilateral sanctions positively contribute to energy efficiency in the case of the full sample of countries. Moreover, the imposition of UN sanctions has a greater decrease on energy efficiency in the target states than the 0.042% reduction of energy efficiency when the sanctionist is the U.S. For robustness, empirical results indicate that the imposition of plurilateral sanctions results in a drop of energy efficiency in Islamic countries, but an increase in non-Islamic countries, while there are also negative shocks induced by the imposition of EU sanctions on energy efficiency in Asian countries, but not for non-Asian countries. We also consider endogenous problems and dynamic specification by using indicator variables and System GMM. In summary, our empirical findings provide policy suggestions for those sanctioned countries about how to maintain energy efficiency when facing international sanctions. 相似文献
50.
沈阳城市周边耕地多功能评价 总被引:4,自引:0,他引:4
[目的]为探索城市化影响下城市周边耕地多功能的现状,分析其空间差异,为耕地保护及城市周边耕地发展提供参考。[方法]从耕地的生产、生态、社会和景观4个功能出发构建评价指标体系,利用熵权法确定指标权重,加权求和法计算单一功能和多功能值,并用ArcGIS进行空间分析,对沈阳城市周边50个乡镇(街道)的耕地多功能性进行综合评价。[结果](1)沈阳城市周边耕地的多功能性空间差异较为明显。生产功能远郊平原区最强,远郊山区和近郊区较弱;生态功能总体偏弱,个别乡镇较好;距离城市越远,社会功能越强;景观功能近郊区较强,远郊区较弱。(2)耕地的生态、社会和景观功能主要受距市中心距离的影响,生产功能受地形和距市中心距离的双重影响,而多功能则受地形、距市中心距离及各乡镇(街道)耕地主导功能等的综合影响。(3)沈阳城市周边的大多数耕地以农业生产为主导,景观文化功能整体相对较弱。近郊区耕地生态功能所占比重较大,但社会功能比重较小,远郊区则与之相反。[结论]沈阳城市周边耕地多功能性空间差异较为明显且不均衡,应科学规划城市周边耕地功能,优化空间布局,协调耕地各功能的关系,促进耕地多功能综合发展。 相似文献