蔗渣改性吸附剂对Cr(Ⅵ)的吸附研究

采用蔗渣纤维素改性吸附剂对Cr(Ⅵ)进行吸附处理,研究了吸附剂用量、吸附时间、pH值和吸附温度对吸附效果的影响。结果表明,最佳的吸附条件为吸附剂用量0.3g、pH值1、吸附温度30℃、时间2h,相应的吸附容量和吸附率分别为1.7mg/g和99.8%。在单因素实验的基础上进行正交实验,由数据分析得到影响蔗渣改性吸附剂对Cr(Ⅵ)吸附效果的因素主次顺序为:pH吸附时间吸附温度吸附剂用量。对吸附剂进行解吸再生实验,结果表明,蔗渣改性吸附剂具有较好的重复使用性及稳定性。     

超声波协同酶法提取银杏黄酮的工艺研究

研究了超声波协同酶法提取银杏黄酮的最佳工艺条件,以总黄酮得率为考察指标,研究了加酶量、pH值、液固比、超声波功率、酶解时间和温度等因素对银杏黄酮得率的影响,并在单因素的基础上通过正交试验对提取工艺条件进行了优化。结果表明:最佳提取工艺条件为加酶量1 mg/g,pH值4.5,液固比10∶1(mL/g),超声功率240 W,时间80 min和温度45℃,此时总黄酮的得率为2.78%。     

β-环糊精接枝聚丙烯酰胺处理含Cr~(3+)废水

以β-环糊精和聚丙烯酰胺为原料,接枝反应合成β-CD-PAM絮凝剂,分别用β-CD-PAM、β-环糊精、聚丙烯酰胺处理模拟含Cr3+废水,研究药品用量、温度、pH值等因素对去除效果的影响。试验结果表明:β-CD-PAM与β-环糊精、聚丙烯酰胺相比,对Cr3+去除能力皆有明显提高;β-CD-PAM处理浓度为10mg/L的Cr3+标准溶液,最优化条件组合为:药品投加量1.5g/L、温度35℃、pH值5⁶,去除率可达到87.23%。     

酶解辅助乙醇法提取土茯苓总黄酮条件研究

本文采用植物复合酶酶解辅助乙醇法提取土获菩总黄酮.以芦丁为标准品,用铝离子显色、紫外一可见分光光度法测定总黄酮含量.采用单因素实验探讨酶添加量、酶解时间和酶解pH值对总黄酮提取率的影响.结果表明:最佳提取条件为酶添加量1.0%,酶解时间3.0h和酶解pH值5.0;最佳条件下,粗提物千粉得率13.9%,干粉中总黄酮含量4.0%,总黄酮提取率为0.53%.     

由鸡毛制取L-胱氨酸的工艺研究

以鸡毛为原料,经过水解、中和、过滤、脱色、结晶等步骤,制取L-胱氨酸.经过正交试验,找到了影响实验结果的主要因素,确定了适宜的工艺条件.水解用盐酸浓度为25%,水解时间为8h,鸡毛与盐酸的配料比为1:2,中和温度为50℃,中和至终点的pH值为4.8,两次脱色活性炭用量分别为粗品量的20%和1.5%,温度为80℃,脱色时间为0.5h.     

超声波制备水性环氧树脂乳液

文章通过超声波制备了水性环氧树脂乳液,探讨了乳化温度、HLB值、乳化剂用量和加水量、超声波等因素对乳液稳定性的影响,结果表明采用十二烷基硫酸钠、辛烷基酚聚氧乙烯(10)醚和聚氧乙烯去水山梨醇单月桂酸酯复配体系,乳化温度为70℃,HLB值为17左右,乳化剂用量占环氧树脂质量的6%⁷%,加水量为乳液总质量的36%,在超声波条件下所制备的乳液稳定性最好,稳定储存可达6个月,并且超声波条件下所制备乳液稳定性显著增加。     

玉米秸秆酶水解影响因素的研究

采用工业使用的两种纤维素酶水解玉米秸秆，并进行了对比。研究了温度、pH值、加酶量、底物浓度、及酶解时间对玉米秸秆水解的影响，以探求最佳的反应条件。     

基于臭氧催化氧化工艺的化工园区污水处理厂提标改造分析

臭氧催化氧化工艺可以应用于污水处理厂提标改造。为确定臭氧催化氧化工艺的最佳反应条件，本文通过试验研究了不同臭氧投加量、不同催化剂用量及不同pH下的化学需氧量（COD）及特征污染物的去除率。结果表明，在化工园区污水处理厂提标改造中，在pH为7～8的条件下，臭氧投加量为50 mg/L，催化剂用量为50 kg时，COD去除率为39.2%，苯胺去除率为40.2%，挥发酚去除率为28.4%，甲醛去除率为17.3%。     

丁草胺在水环境中降解规律的研究

论述了pH值、微生物、太阳光照和温度对丁草胺在水样中降解的影响。结果表明。影响丁草胺在水环境中降解的因素依次为pH值、微生物、太阳光照和温度。太阳光照的影响程度较低，而pH值、微生物和温度的影响程度较高。水中的OH^-会对丁草胺的降解有催化作用，另外，水中存在的微生物可加快丁草胺的降解速率；丁草胺在温度较高条件下降解的速率较快。     

双酶法制糖过滤问题的讨论

从双酶法制糖的滤渣成分分析可知,影响过滤速度的主要因素为两大类,一类为蛋白质类,另一类为糊精类(包括不容性淀粉颗粒即老化的糊精).     

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.     

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.     

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.     

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.     

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.     

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.