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ON THE EXPLOITATION AND SUSTAINED UTILIZATION OF REGIONAL RESOURCES, TAKING THE DEVELOPMENT PROGRAM TO TAME THE HUANGHUAIHAI PLAIN AS AN EXAMPLE

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Bulletin of the Chinese Academy of Sciences 1995年第3期9卷 257-264页

作者： Shi Yuanchun(beijing university of agriculture)

The Huanghuaihai Plain is noted for its vast landmass, complex natural conditions and development problems to overcome. This article lists the achievements and experiences obtained by Chinese agrotechnicians during the past two decades in the comprehensive reclamation of the Plain, and based on these, it explores the potential of the Plain to make up the increasingly scarce local resources by S&T means.

关键词：刃口知心内曲

CHINA'S INDISPENSABLE WAY TO GRAIN SELF-SUFFICIENCY

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Bulletin of the Chinese Academy of Sciences 1997年第1期11卷 73-76页

作者： Lou Chenghou(beijing university of agriculture)

In China’s countryside today, so far the foodstuffs for daily-life subsistence are still taken from the traditional farming production in addition to the yield of animal husbandry, while crop plantation takes the lion’s share in our rural economy. During the Medieval Age of the Western countries, however, special stress was placed on raising livestock on pastureland until the Industrial Revolution occurred in the 18th century when grain-oriented agriculture came into being. As a result of the unprecedented boom of modern science and technology now sweeping the whole world, farming productivity has sky-

关键词： CHINA’S INDISPENSABLE WAY TO GRAIN SELF-SUFFICIENCY

Simulation and Analysis of OSPFv2 DR Election Based on GNS

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Simulation and Analysis of OSPFv2 DR Election Based on GNS

2012 National Conference on Information Technology and Computer Science

作者： Xiaohua Li School of Computer and Information Engineering beijing university of agriculture beijing,China Jian Xu School of Computer and Information Engineering beijing university of agriculture beijing,China Juan Nie School of Computer and Information Engineering beijing university of agriculture beijing,China Chengkui Guo School of Computer and Information Engineering beijing university of agriculture beijing,China Xiangang Zhao National Satellite Meteorological Center China Meteorological Administration beijing,China

Designated Router （DR） is the key for the quality of an Open Shortest Path First （OSPF） network and it enables a reduction in the number of adjacencies,which in turn reduces the amount of routing protocol traffic and the size of the Link State Database （LSDB）.In this paper,we analyze the principle of OSPFv2’s DR election algorithm and carry out the simulation based on *** simulation can provide a reference for building an OSPF *** the simulations,we focus on two types of DR Election process:Normal DR Election and DR *** results show that the election of DR and BDR can reduce the amount of OSPF traffic and ensure an orderly transition from Backup Designated Router to Designated ***,through the simulation we also learn that lots of unnecessary DR election operations are executed,which consume the routers’ CPU resource and occupy their processing *** improve the election algorithm,we offer several *** detach and subdivide the NeighborChange event that invokes the election algorithm into more specific *** these measures,the DR election algorithm is expected to dispense with the extra election,reduce network convergence speed,and thereby improve network performance.

关键词： OSPF DR BDR DR Election GNS

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农业生态系统中氮素造成的非点源污染

农业环境保护 1998年第1期17卷 35-39页

作者：吕耀中国农业大学农学系

施入农业生态系统（土壤）中的氮素，除一部分被作物吸收外，其余大部分经径流、淋溶、农田排水等形式流失。畜禽养殖场所排废水中的氮素也主要进入地表水和地下水中。氮素流入对水域的污染为非点源污染，主要导致地表水的富营养化、地... 详细信息

施入农业生态系统（土壤）中的氮素，除一部分被作物吸收外，其余大部分经径流、淋溶、农田排水等形式流失。畜禽养殖场所排废水中的氮素也主要进入地表水和地下水中。氮素流入对水域的污染为非点源污染，主要导致地表水的富营养化、地下水硝酸盐含量过高等。解决途径是确定合理施肥量和平衡施肥，并对畜禽粪便进行处理利用。

关键词：农业生态系统氮素非点源污染土壤污染

Antifungal Activity of Extracts of Stellera chamaejasme Against Botrytis cinerea

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Antifungal Activity of Extracts of Stellera chamaejasme Agai...

2010 International Colloquium on Computing,Communication, Control, and Management (CCCM2010)

作者： Lei Zhao Key Laboratory of Urban agriculture (North) of Ministry of agriculture P. R. China beijing university of agriculture beijing, China You-nian Wang, Juan Du, Chun-ya Bu, Lan-qing Ma, Yu-bo Liu, Guang-lu Shi Key Laboratory of Urban agriculture (North) of Ministry of agriculture P. R. China beijing university of agriculture beijing, China

The antifungal activity of the extracts from Stellera chamaejasme against Botrytis cinerea was investigated in our work. The active components of Stellera chamaejasme extraction were primary analyzed by bioactive tracking method followed by separation of the highly active components by column chromatography, and then the structure of the final extract was identified by liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR). The results showed that the main antifungal bioactive compound in the eluotropic component 3 was umbelliferone. And a positive correlation between umbelliferone concentration and antifungal activity was observed. The minimal inhibitory concentration (MIC) of umbelliferone was 1.52 mg ml-1. Depending on the analysis of ultrastructure by scanning electron microscope (SEM), it was found that the morphology of Botrytis cinerea spore and mycelium were obviously destroyed by umbelliferone existing in eluotropic component 3.

关键词： Stellera chamaejasme Umbelliferone LC-MS, Botrytis cinerea Antifungal activity

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超声波法提取苦荞甾醇工艺研究

中国食品学报 2013年第5期13卷 32-38页

作者：何焕肖马挺军徐艺青北京农学院食品科学与工程学院北京102206

研究了超声波法提取苦荞甾醇的工艺参数,采用硅胶柱色谱法纯化提取的植物甾醇。以提取物中植物甾醇含量为指标,筛选植物甾醇理想的提取溶剂。通过单因素试验选择适合的水平,通过响应面试验确定它们之间的相互作用。优化的超声波法提取... 详细信息

研究了超声波法提取苦荞甾醇的工艺参数,采用硅胶柱色谱法纯化提取的植物甾醇。以提取物中植物甾醇含量为指标,筛选植物甾醇理想的提取溶剂。通过单因素试验选择适合的水平,通过响应面试验确定它们之间的相互作用。优化的超声波法提取苦荞甾醇的工艺:提取剂乙醇,液料比24.06mL/g,超声波功率300W,时间59.7min,温度60℃。在此条件下提取,提取物中植物甾醇含量高达2.6653mg/g。经硅胶柱色谱纯化,荞麦甾醇纯度在95%以上。

关键词：苦荞麦植物甾醇超声波提取

肠艾美耳球虫内生发育阶段超微结构研究——Ⅲ.小配子发育

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畜牧兽医学报 1993年第3期24卷 270-276页

作者：刘群孔繁瑶殷佩云北京农业大学兽医学院

肠艾美耳球虫(Eimeria intestinalis)小配子体及小配子的发育均在宿主细胞的带虫空泡内进行,带虫空泡内含有较多的泡内小管以及由小配子体逸出的线粒体和基质小体。多核小配子体是由最初的单核小配子体发育而成。小配子的形成首先是中... 详细信息

肠艾美耳球虫(Eimeria intestinalis)小配子体及小配子的发育均在宿主细胞的带虫空泡内进行,带虫空泡内含有较多的泡内小管以及由小配子体逸出的线粒体和基质小体。多核小配子体是由最初的单核小配子体发育而成。小配子的形成首先是中心粒转变成鞭毛的基粒,此后鞭毛和顶体与小配子体成切线方式长入带虫空泡;几个小线粒体融合成一大线粒体,嵌于核前方一侧,与核一起突入带虫空泡。成熟的小配子体长约6.5μm,有两根鞭毛。鞭毛的横断面为9+2的微管结构。体部由顶体、线粒体和核组成。由顶体的腹侧向后发出4～6根微管,其中只有2～3根延伸到体后部。

关键词：超微结构肠艾美耳球虫小配子

Difference in Photosynthetic Performance among Three Peach Cultivars Grown under Low Light Conditions in Greenhouses

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Difference in Photosynthetic Performance among Three Peach C...

2009整合植物生物学研讨会

作者： Shaohui Wang,Yun Kong and Yuncong Yao~* Plant Science & Technology Department,beijing university of agriculture,beijing 102206,China.

The objective of this paper was to investigate the photosynthetic performance of three peach varieties(’Qingfeng’,’NJN76’ and ’Maixiang’)under low PPFD(Photosynthetic Photon Flux Density)condition(100%PPFD as control(CK),90%PPFD(T1),and 70% PPFD(T2))simulated by the cover of layers of film in the *** results showed

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The Preparation of Referance Material for Positive Control of Plum Pox Virus and Arabis Mosaic Virus

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The Preparation of Referance Material for Positive Control o...

中国植物病理学会第九届全国会员代表大会暨2010年学术年会

作者： TIAN Yong-lei~1,LIU Dong-mei~2,GAO Ya-hong~3,LI Ming-fu~(1**) (1.Chinese Academy of Inspection and Quarantine,beijing 100121 2.China agriculture university, beijing 100193 3.beijing university of agriculture,beijing 102206)

Plum pox virus(PPV) and Arabis mosaic virus(ArMV) are two kinds of entry quarantine pests in China,which have potential threat to the safety of agricultural products and *** accurate identification of the above viruses is of great important significance for preventing the *** the quarantine and identification system of plant virus,standard positive reference is important to maintain the stability and reliability of the testing methods,but there is biosafety hazard if using the infected materials *** this study we constructed the recombinant plasmids which contain the coat protein gene of PPV and ArMV respectively as the positive reference for PCR testing by the technology of DNA recombination and prokaryotic expression,besides we also constructed the prokaryotic vector and expressed the specified coat protein as the positive reference for serological testing.

关键词： Plum pox virus Arabis mosaic virus Referance material for positive control