粉煤灰制备复合固体酸环境友好催化剂影响因素的探讨

以粉煤灰为主要原料采用沉淀一浸渍法制备FZS型复舍固体酸催化剂，对影响催化剂硫含量、比表面、催化性能等因素进行考察。通过TEM等手段对催化剂结构予以表征。实验结果表明：粉／锆比为3：1、H2SO4浸渍浓度为0．50mol／L、焙烧温度在550℃时制备的催化剂，应用于酯化反应中酯化率可达98.3％。     

玉米秸秆浓硫酸水解的初步研究

初步探讨了利用浓硫酸对玉米秸进行水解的影响因素，酸浓度、反应温度、固液比、粒度及灰分含量对水解效率都有一定影响。     

由磷肥企业副产氟硅酸制备氟化钠的研究

重点介绍了以磷肥企业副产氟硅酸为原料制备氟化钠的新工艺。首先用氨水氨化脱硅得到氟化铵溶液,再向氟化铵溶液加氯化钠合成氟化钠。对影响反应的温度、时间、物料配比等因素进行了探讨,得出具体工艺为:(1)氨化反应:H2SiF6浓度在12%～14%之间,氨水过量25%,反应温度为60～70℃,反应时间120min。(2)氟化钠合成:氯化钠过量15%～20%,反应温度85～90℃。产物氟化钠纯度大于98%,收率大于80%。     

利用铁氧化皮制备聚合硫酸铁

以铁氧化皮为原料,经过酸溶—氧化—过滤三个步骤,制得合格的液体聚合硫酸铁产品。通过考察酸溶阶段的硫酸用量、硫酸浓度、温度、时间对铁浸出率和产品盐基度的影响,确定最佳的生产工艺为:硫酸用量为反应理论值的0.9、硫酸浓度为30%、氧化皮溶解温度为80℃、氧化皮溶解时间为3~4 h。所得液体产品指标为:外观红棕色、铁含量11.7%、盐基度13%,其他指标符合国家相关标准。对现有的废弃物进行了综合利用,不产生有害物质,减少了环境污染,并且能创造一定的经济价值。     

印尼某红土镍矿浸出试验研究

试验考察了酸量、浸出温度、矿浆浓度和浸出时间等因素对镍、钴、铁浸出率的影响。试验结果表明,镍、钴、铁浸出率随着酸量的增加而提高,但酸量过大会造成酸耗大、铁浸出率升高,加大后续沉铁的困难;升高温度,镍、钴、铁的浸出率均有所增加,温度大于85℃后,增加幅度不明显;矿浆浓度和浸出时间对镍、钴、铁的浸出率影响较小。本试验最优化条件为:酸矿比(t/t矿)为1.2、浸出温度95℃、矿浆浓度33%、浸出时间3 h。在此条件下,镍、钴、铁的浸出率分别为97.43%、88.56%、85.68%。     

国外某氧化铜矿的浸出研究

以国外某氧化铜矿床为研究对象,本文采用硫酸酸浸工艺,考察浸出时间、反应温度、液固比、硫酸消耗、磨矿粒度等因素对铜浸出率的影响,得到最佳浸出条件。研究表明,提高浸出温度和酸矿比,混合矿Cu浸出率有所提高,但是增幅较小,同时杂质Fe浸出率增大。浸出温度升高,酸耗相应增大。因此,推荐室温下浸出,酸矿比130 kg/t,浸出时间2 h,此时Cu浸出率约为92%。此外,矿石粒度对Cu的浸出率无明显影响。     

葡萄糖还原浸出低品位钴土矿工艺及动力学研究

采用葡萄糖为还原剂,在硫酸体系中进行低品位钴土矿进行直接浸出,研究浸出过程的工艺条件和动力学。实验结果表明:在硫酸初始浓度1.6 mol/L,葡萄糖初始浓度5 g/L,反应温度95℃,浸出时间6 h,液固比3∶1的条件下,钴土矿中Co和Mn的浸出率可同时达到99%以上。动力学研究表明:钴的浸出过程在75~95℃内符合未反应核缩减模型,浸出过程主要受内扩散步骤控制,浸出表观活化能为21.03 k J/mol。     

用蛋壳制备补钙口服液的研究

以鸡蛋壳为原料,制备醋酸钙口服液,研究原料配比、反应物浓度、反应温度、时间等因素对产物的影响。在最佳工艺条件下,产品收率可达94.6%,纯度>95%。     

锌电解液净化铜渣除氯工艺研究

本文采用铜渣法脱除锌电解液中的氯,并考察了反应温度、溶液酸度、铜渣用量、初始铜离子浓度和反应时间对除氯效果的影响,以优化除氯工艺参数。试验结果表明,在初始溶液硫酸酸度10 g/L,反应温度60℃,铜渣3倍理论用量,溶液初始铜离子浓度1.5 g/L,反应时间1 h的优化条件下,溶液中氯离子脱除效果好,氯离子脱除率可达88%,溶液中氯离子含量降至74 mg/L,满足电解要求。     

莽草酸多样化高值化利用 等

Green? Chemistry:莽草酸为我国特色战略资源八角中的主要水溶性组 分，主要存在于木兰科植物八角茴 香的干燥成熟果实之中，其含量可 高达12%～14%。我国是世界八角 的主产国，种植面积及产量均占全 世界的80%以上。由于莽草酸主要 从八角树的枝、叶及果中获取，其 获取过程不危害植物及环境，且现 代生物工程技术已建立以E.coli为 载体，以葡萄糖为原料高收率地制备得到莽草酸的工业化 方法。因此，莽草酸属真正意义上的可再生、非粮生物质 资源。但是，到目前为止，莽草酸的应用范围较为局限， 主要用于合成抗流感药物磷酸奥司米韦(Tamiflu)，亟待拓 展其多样化、高值化利用空间，进一步开发其作为可再生 资源的利用价值。中科院广州化学有限公司(中国科学院 广州化学研究所)的研究人员对伯胺参与的莽草酸衍生物 的芳构化反应进行了研究，首次提出并初步构建了伯胺参 与的莽草酸芳构化衍生的方法学，为现代绿色化学领域的研究提供了新的、可借鉴的思路。     

On the Major Transformation of the Asia-Pacific Regional Structure北大核心CSSCISSCI

Recent years have witnessedsignificant changes in the Asia-Pacific regionalstructure featuring the shift in power balance among related countries as well as adjust-ments in their respective regional strategies. So what is the prevailing trend in thistransformation and what kind of regional order will likely emerge in the future？ To an-swer these questions, the paper tries to explore the following dimensions： the evolvingregional context, shift in power balance and power conversion, geo-political and geo-e-conomic developments and interactions between them, and evolving regional order. Asthe study shows, the broadening of regional geographical scope, the rise in the numberof actors involved, as well as changesin the relations among them, have combined tocast a pluralistic and complex flavor to the regional structure. While the power balanceamong China, the United States and Japan shifts, and power conversion is also occur-ring. China and Japan are paying increasing attention to their security roles, whereasthe United States under the Obama administration laid more stress on expanding itsgeo-economic clout. In spite of the intensifying geopolitical competition among China,the United States and Japan in recent years, a Sino-US strategic compromise-whichholds the key to regional geopolitics-isother front, some kind of geo-economicmore likely to take place in the future. On thecooperation will probably emerge. In the longerterm, it will be the geo-economic trend thatwill prevail over the geopolitical trend inthe region. Finally, the future evolution of regional order wiI1 mainly follow the eco-nomic logic, accompanied by the dilutionof its hegemonic and hierarchical nature.Hence, a pluralistic and complex regional community will emerge.     

The German Hanse and Bergen – new perspectives on an old subject

Abstract

The Hanseatic League and her kontors (trading posts) were an integral part of the medieval trade system in Northern Europe. Hanse merchants dominated many markets in this region and managed to maintain a monopoly-like role in towns like Novgorod and Bergen for many centuries. Consequently, one focus of historical research about the Hanseatic League lay on the mechanisms that enabled the Hanse merchants to keep that strong of a position for such a long time.

This article is part of the discussion about this topic. Based on Lübeck merchants with business interest in the Norwegian town of Bergen, the so-called Bergenfahrers (Bergen travellers), it will give new insights into the Hansards' economical and social organization. The three main points are (a) the integration of the Bergen market in the Hanseatic trade network as an intermediary trading place on the vivid East–West route of Hanse trade; (b) the importance of the Bergenfahrers within the Hanse merchants' economical, social and political networks; and (c) the structure of the Bergenfahrers network patterns in the late Middle Ages.

In addition to new insights into the important role of Bergen and the Bergenfahrers within Lübeck's and the other Wendish Hanse towns' trading system, this articles provides further proof for the usefulness of the methods of Social Network Analysis in medieval economic research.     

Organization and incentives in the age of sail

The British Navy in the age of sail was the most successful bureaucracy of its time. Its organization and incentive structures differed importantly from contemporaneous private sailing ventures, but closely resembled those of today’s large corporations. To induce efficient effort, the navy used a hierarchical tournament, in which sailors competed for higher pay that came with promotions based on relative performance. Promotion probabilities, the option value of future promotions, and the higher effort required of men in higher ranks and on larger vessels, combined to yield a highly skewed pay structure.     

Financial Reporting and Trade Credit: Evidence from Mandatory IFRS Adoption*

We investigate the effect of mandatory IFRS adoption on trade credit. We document that firms in countries that adopt IFRS receive more trade credit from their suppliers, consistent with improved financial reporting quality and comparability playing a role in facilitating informal financing. This increase is larger for countries with a low level of societal trust, a poor pre‐IFRS‐adoption information environment, and stronger legal enforcement. These cross‐sectional results suggest that the conditions under which higher‐quality information is made publicly available affect suppliers' decisions to provide trade credit. This increase is also larger for firms with greater exposure to foreign markets, a finding that highlights the importance of more comparable international financial reporting standards in facilitating cross‐country trade credit. We also find that IFRS adoption has a stronger positive effect on trade credit for firms with greater liquidity needs. Finally, we find that firms in countries that adopt IFRS also extend more trade credit to their customers. Overall, our results support the notion that financial reporting can have a causal effect on trade credit.     

中俄经济技术合作面临新机遇

中俄在十年内把各自的GDP翻一番的目标,为发展中俄经济技术合作提供了机遇.仅仅依靠商品贸易的增长很难大幅度提升中俄经贸关系,需要全面开展经济技术合作,特别是加强在自然资源开发、跨国投资、军工技术和产品贸易领域的合作.     

INFRASTRUCTURE POLICY IN INDONESIA, 1965–2015: A SURVEY

This survey, first, provides an overview of the main developments in the infrastructure sector in Indonesia during the past five decades and, second, considers what the main policy and management bottlenecks in infrastructure appear to be. The overview of main developments indicates that, in broad terms, most parts of the sector have expanded considerably but that the needs remain acute for further expansion and for attention to the maintenance of existing facilities. Demand for infrastructure is high, especially since the regulated prices set for infrastructure services are often low. Access is often difficult, however, because of shortages of infrastructure, and quality is often unsatisfactory because of poor maintenance and indifferent management. These problems of access are exacerbated by the regulation of prices. This overview also points to the markedly different performances of industries in which pro-competitive policies have been applied and those in which more traditional policies of close regulation have restricted the operation of markets.     

Integrated educational management for the universities

The research model investigates the integrated form of educational management for the universities. To enhance the operations, generate quality outcomes for the well-being of the society, this exploratory study depicts the two wings for the universities in four aspects including education development, education assessment, research development and research assessment. For the better understanding of education and research wings of the universities, the researchers identify different factors namely programs establishments, university culture, faculty capabilities and facilities those have been formularized by the structural equation modeling （SEM） through AMOS. The survey questionnaire was developed and analyzed the reliability and validity of the tools. The conceptual model for the universities provides a novel approach for decision makers to review and appraise their performance toward fulfillment of ultimate goals, i.e. producing high-caliber graduates and high-impact research outcomes for the betterment of the society. This research represents two contributions to the society including human resource contribution and research contribution.     

基于DEA方法的我国证券公司效率的实证分析

选取了具有一定代表性的证券公司为样本,根据2006年至2008年的财务数据,运用DEA的C2R模型和BC2模型来分析计算他们的技术效率、纯技术效率、以及规模效率。然后通过对不同证券公司的分析,揭示我国证券公司整体上的现状。