玉米秸秆制备木糖工艺的研究

以超声波为强化手段,稀硫酸为催化剂,水解提取玉米秸秆中的木糖,利用DNS法对木糖溶液进行分析。考察了玉米秸秆制备木糖时秸秆水分、粒度、硫酸浓度、固液比、水解温度、反应时间及超声波强化对木糖收率的影响规律。研究得出最佳制备条件为：秸秆粒度约为40目,硫酸浓度为3％。固液比为1：10;预处理条件为：超声频率100KHz,超声时间为1h,超声温度为20～25℃,水解温度为100-102℃,反应时间为5h。在此条件下,木糖最高收率达到32．06％。     

关于秸秆综合利用的思考

户县每年玉米种植面积在40万亩左右，产生大量的玉米秸秆，这些秸秆堆弃在田间、路旁，给农业生产和交通带来不便。为了处理大量农业废弃秸秆，户县农业机械公司购入农业秸秆还田机械，户县60％以上的秋季农作物秸秆都进行了粉碎还田，既为农业发展奠定了基础。同时又为土地增添了有机农家肥，还为秸秆无害化处理找到了出路。     

利用玉米秸秆、鸡粪资源开发粗饲料的研究

玉米秸秆和鸡粪混贮，可以生产质量较高的反刍动物饲料。这个途径改善了玉米秸青贮的发酵特性和产品品质，增加了玉米秸秆的营养成分，在减少资源浪费、产生很好的经济效益的同时，也能减少农业废弃物对环境的污染。     

冬季防治玉米螟

冬季防治玉米螟玉米螟是玉米生长期的大敌。它不仅繁殖快，每年２～３代，而且危害时间长，不论是春播玉米，还是夏播玉米均会遭危害。可采取以下办法防治：一、对有玉米螟害虫的玉米秸秆，要及时清除进行集中烧毁，以杀死越冬虫、蛹。二、用于还田的玉米秸秆，要用铡刀铡...     

玉米秸秆能源化利用途径与方法

通过气化、液化、固化和炭化技术,将玉米秸秆转化为优质能源品种,替代煤炭、石油、天然气等燃料缓解地球能源危机。主要介绍了玉米秸秆气化、液化、固化和炭化的主要方法与利用途径,分析了玉米秸秆利用技术的国内外研究现状与发展前景。     

不同水氮条件下小麦和玉米秸秆养分释放特征研究

采用尼龙网袋法,模拟小麦玉米种植模式,研究了不同水氮条件下冬小麦和夏玉米秸秆养分释放特征。研究表明,小麦秸秆和玉米秸秆腐解情况都表现为前期腐解快,后期腐解速度缓慢;室内培养条件下,腐解前20天为腐解快速期,腐解缓慢期大约为20~60天,其后为腐解停滞期。玉米秸秆腐解速度比小麦秸秆快。添加氮素对加快秸秆腐解有一定的效果。土壤含水量为16%和20%对秸秆腐解速度无影响。小麦与玉米秸秆中养分释放率均表现为KPCN,小麦和玉米秸秆中养分的释放量均表现为CKNP。     

青纱账里“拉脚客”

“车车秸秆如山高，白里黑里尽操劳，运给奶牛作干粮，秸秆堆出‘金元宝’。“每到如今这个时段的秋收时节．在济南市历城区王舍人镇就活跃着一支清运玉米秸秆的务工队伍。     

不同秸秆还田方式对土壤有机质及速效养分的影响

为探明不同秸秆还田方式对大田表层(0~5cm)土壤有机质及速效养分的影响,设置4种不同秸秆还田方式:秸秆不还田(CK)、秸秆焚烧还田(SA)、秸秆粉碎还田(SC)、秸秆高留茬还田(SH)。结果表明:秸秆直接还田(SC、SH)显著提高了土壤有机质含量(P0.05),在玉米苗期、大喇叭口期、成熟期相比CK提高幅度分别为0.5%~5.3%、2.6%~9.5%、4.5%~18.9%;秸秆焚烧还田降低了土壤有机质含量,各时期分别比CK降低8.9%、14.7%、8.5%。对速效磷、速效钾的影响,各处理表现为SCSHSACK,经过玉米生育期,三种还田处理的速效磷、速效钾含量分别比CK提高了24.5%~53.9%、24.6%~70.9%。玉米生育期内,SA、SC、SH的速效氮(硝态氮、铵态氮)含量相比CK的增加幅度呈现先减小后增加的趋势。SC的硝态氮含量在玉米苗期和大喇叭口期高于其他处理,铵态氮含量在玉米成熟期高于其他处理;SA的硝态氮含量在玉米成熟期高于其他处理,铵态氮含量在玉米苗期和大喇叭口期高于其他处理;经过玉米生育期,三种还田处理的硝态氮、铵态氮分别比CK提高了9.4%~57.2%,10.5%~50.2%。综合各项指标,秸秆粉碎还田处理对土壤有机质和速效养分的积累有最明显的作用。     

植物纤维素的水解利用研究进展

本文简要介绍植物纤维素的水解利用的研究进展，内容包括各种预处理方法及酶解效果、酶回收现状。     

碳氮比对猪粪-玉米秸秆混合堆肥的影响

本文选用猪粪与玉米秸秆为原料,研究了碳氮比对猪粪-玉米秸秆混合堆肥的影响,比较堆肥过程中堆体各项指标的差异,根据T值和种子发芽指数进一步评价腐熟度,结果表明,C/N值为20时处理腐熟效果最好。堆肥结束后,猪粪-玉米秸秆混合物中的重金属含量显著增加,但均符合《有机肥料》(NY525-2012)标准限量要求,可以作为肥料施用。     

Penetration and Post-infection Development of Meloidogyne Incognita on Tobacco as Treated by Rhizobacteria Pseudomonas Fluorescens Strain P-72-10

The bio-control potential of rhizospere bacteria Pseudomonas fluorescens against plant-parasite nematode had been demonstrated. P. fluorescens had shown the effect to enhance tobacco resistance to root-knot nematode Meloidogyne incognita. Inoculation with P. fluoreseens in tobacco could lead to significant reductions in the number of juveniles that penetrated tobacco root and further life stage development of the juveniles. The number of juveniles penetrated into tobac- co root in treatment with P. fluorescens is significantly different from CK at 2DAI, 6DAI, 8DAI and 10DAI. Significant reduction and delayed development of juveniles that penetrated into tobacco root and treated were observed in treatment at 14DAI, 21DAI, 28DAI and 35DAI. In addition, P. fluoreseens treatment leads to a significant reduction in the number of eggs per egg-mass at 35 DAI. The results show P. fluorescens induced a continuously suppression on root-knot nema- tode M. incognita throughout their entire early infection phase of root penetration, subsequent life stage development and reproduction.     

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.     

For Better or for Worse? Local Impacts of the Decentralization of Indonesia’s Forest Sector

This paper quantifies the local impacts of mechanized logging on forest-dependent communities in Indonesia, before and after decentralization. A conceptual framework incorporates financial, social, enforcement, rent-seeking, and environmental impacts. Using data from 60 communities in East Kalimantan, the empirical results suggest that significantly more households received financial and in-kind benefits after decentralization compared to before. Many communities engaged in self-enforcement activities against firms both before and after decentralization. Post-decentralization, a significantly higher proportion of households perceived community forest ownership. There were few significant differences in perceived environmental impacts. Little evidence exists of a post-decentralization trade-off between environmental and financial contractual provisions.     

以资本管理为核心的银行治理综合评价指标研究

商业银行的特殊性体现在风险性、外部性和多重治理目标上，尤其集中体现在风险管理的本质上。风险管理日益成为现代商业银行的主体活动和核心职能，资本管理成为现代商业银行风险管理的核心。在整合EVA和RAROC指标的基础上。文章构建了以资本管理为核心的银行治理的综合评价指标，以求真实反映银行经营的成果，有效衡量风险收益和风险成本的对比关系，从而反映以资本管理为核心的银行风险管理的过程、能力和效率。     

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.     

Markteintrittstiming von Telekommunikationsdiensteanbietern

Zusammenfassung Die vorliegende Studie analysiert für 87 Neuprodukteinführungen (NPE) und Auslandsmarkteintritte (AME) von Telekommunikations(TK)-Diensteanbietern in Deutschland, zu denen 42 Schlüsselinformanten in einer schriftlichen Befragung Auskunft gaben, (1) inwieweit deren zeitliche Eintrittspositionierung durch Marktcharakteristika und Unternehmensressourcen erkl?rbar ist sowie (2) inwieweit und gegebenenfalls unter welchen unternehmensexternen und -internen Situationsbedingungen deren Markteintrittstiming mit dem wahrgenommenen Eintrittserfolg assoziiert ist. Ein früher Markteintritt wurde dann realisiert, wenn die Wettbewerbsintensit?t im adressierten Gesch?ft niedrig und das Budget für den Expansionsschritt überdurchschnittlich ausfielen. Zwischen dem Markteintrittstiming und der Beurteilung des Eintrittserfolgs bestand ein nicht monotoner, umgekehrt U-f?rmiger Zusammenhang: Frühe Folger wiesen signifikant bessere Erfolgswerte auf als Pioniere und sp?te Folger, deren Erfolgsniveaus nicht signifikant divergierten. In einer Industrie, die durch starke externe Netzeffekte gepr?gt ist, fallen offenbar die Nachteile eines Markteintritts als Pionier oder sp?ter Folger st?rker ins Gewicht als die Vorteile dieser beiden zeitlichen Eintrittspositionierungen. Unabh?ngig vom Markteintrittstiming wurden NPE/AME von TK-Unternehmen als erfolgreicher eingestuft, wenn sie sich in einen Markt mit stark wachsender Nachfrage und aufeinander abgestimmt (re)agierenden Wettbewerbern mit qualitativ überdurchschnittlichen, abw?rtskompatiblen, erprobbaren und wenig erkl?rungsbedürftigen TK-Diensten engagierten.      

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.