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The transformation of agriculture in Brazil through development and adoption of Zero Tillage Conservation Agriculture

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International Soil and Water Conservation research 2014年第1期2卷 35-46页

作者： P.L.de Freitas J.N.Landers Brazilian Agricultural research Corporation-National Centre for Soil research(Embrapa Soils) Agronomist M.Sc.Hon.DirectorZero Tillage Farmers’Association for the Cerrado Region of Brazil

The soil conservation movement in Brazil has been a major driving force in the continuing search for agricultural farming systems that are more sustainable than what we have today,particularly in tropical and subtropical *** development and adoption of Zero Tillage Conservation Agriculture(ZT/CA)was the key to the success of this movement,generating agricultural,environmental,and societal *** of the ZT/CA philosophy and technologies is currently practiced on more than 50%of the annual crop *** is due to the work and innovations of pioneering farmers,agronomists,researchers,and consultants that were and are involved in these *** extensive adoption of ZT/CA occurred after many unsuccessful efforts to mitigate against the devastating effects of soil erosion that were threatening the entire agricultural industry in *** and farmers realized that erosion control required continual cover of the soil to guard against the torrential rain storms common to these *** triggered the efforts of soil conservation pioneers at different points in time and regions of *** southern Brazil,Herbert Bartz,watched his topsoil eroding away in torrents of *** set him thinking and searching for alternatives,resulting in his adoption of ZT/CA farming in *** years later in Brazil’s centre-western savannah(Cerrado biome),farmers,researchers,crop consultants and agro-industry initiated efforts to expand cultivation into the very difficult production region of the *** was successfully achieved through the pioneering work of agronomist John Landers,bringing experience from the ZT/CA farmer association networks in the *** were the turning points in the sustainable development of annual crop farming in ***,society recognizes the role of these pioneers as key to achieving social,economic and environmental ***/CA reversed the historically accelerating degradation of soil organic matter

关键词： Soil conservation Zero tillage Conservation agriculture Sustainable soil management Soil organic matter

Hack's law of debris-flow basins

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International Journal of Sediment research 2009年第1期24卷 74-87页

作者： LEE C. F BEIGHLEY R. E Department of Civil Engineering The University of Hong Kong Pokfulam Road 2. Director Soil Erosion Research Laboratory Department of Civil Construction and Environmental Engineering San Diego State University

Hack’s law was originally derived from basin statistics for varied spatial scales and regions. The exponent value of the law has been shown to vary between 0.47 and 0.70,causing uncertainty in its application. This paper focuses on the emergence of Hack’s law from debris-flow basins in China. Over 5,000 debris-flow basins in different regions of China with drainage areas less than 100km2 are included in this study. Basins in the different regions are found to present similar distributions. Hack’s law is derived from maximum probability and conditional distributions,suggesting that the law should describe some critical state of basin evolution. Results suggest the exponent value is approximately 0.5. Further analysis indicates that Hack’s law is related to other scaling laws underlying the evolution of a basin and that the exponent is not dependent on basin shape but rather on the evolutionary stage. A case study of a well known debris-flow basin further confirms Hack’s law and its implications in basin evolution.

关键词： Debris-flow basins Hack’s law Scaling laws Basin evolution

International Natural Gas Market and Prospects for Sino-Russian Cooperation

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Contemporary International Relations 2010年第6期20卷 23-33页

作者： Feng Yujun research Professor and director of the Institute of Russian Studies CICIR

During the visit by Russian President Dmitri Medvedev to China in September 2010, the China National Petroleum Corporation (CNPC) and Gazprom signed a 'Protocol on Basic Conditions of Natural

关键词：天然气市场中国石油天然气集团公司俄罗斯总统天然气供应合作展望国际天然气公司

Foreign Contacts of the Communist Party of China

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China Today 2011年第7期60卷 26-29页

作者： KONG GENHONG is a deputy director of the Contemporary World research Center.Dr. Deputy director of the Contemporary World research Center

THE Communist Party of China is a political party that is firmly rooted in national conditions,attaches great importance to contacts with the outside world,and excels in absorbing advanced experience from beyond its *** Party has sustained international exchanges throughout its 90-year *** the course of the Chinese revolution,construction of New China and its later reforms,its outstanding ability to avidly develop foreign relations and make positive use of them is one of the secrets of its continuing success.

关键词：中国共产党对外交往国际交流外交关系国内外新中国

Niobium in Microalloyed Steels Unchallenged for Its Main Applications

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Journal of Iron and Steel research International 2011年第S1期18卷 57-65页

作者： Nogueira Marcos A Stuart Carneiro Tadeu Companhia Brasileira de Metalurgia e Minerao Technical DirectorSao PauloBrazil Companhia Brasileira de Metalurgia e Minerao Managing DirectorSao PauloBrazil

During the past five decades niobium has emerged as the most important microalloying element in high strength *** first theories to explain its role were presented in the seminal publications of Woodhead,Morrison and *** niobium microalloyed steels are unchallenged for their main *** examples include linepipe for gas transportation,automotive steels used in body-in-white and structural parts,shipbuilding,steel towers and steel structures in civil construction that exhibit better fire resistance and seismic load *** technology for steelmaking helped emphasize the superior overall properties that can be attained with the use of *** linepipe is the best example of cleaner steel with carbon levels below 0.05% manufactured *** niobium microalloyed steels present the optimal balance of strength,toughness,weldability and *** paper describes the evolution of the technology associated with niobium in microalloyed steels,technology that secured its status as the efficient solution to solving today’s challenges:safety,energy efficiency and environmental *** paper also presents evidence that enhances the case that there is a secure,stable,long-term supply of the ferroniobium used to manufacture these steels.

关键词： Niobium in Microalloyed Steels Unchallenged for Its Main Applications

Twin lintel belt in steel for seismic strengthening of brick masonry buildings

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Earthquake Engineering and Engineering Vibration 2004年第2期3卷 215-222页

作者： C.V.R.Murty Jayanta Dutta S.K.Agrawal Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India professor Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India Formerly Graduate student Structural Engineering research Division Central Building Research InstituteRoorkee 247667India Senior Assistant Director

A single-room,single-storey full-scale brick masonry building with precast RC roofing system was tested thrice under displacement controlled lateral cyclic loading,to assess the effectiveness of the basic repair and seismic strengthening ***,the virgin building specimen was loaded laterally to f^*** the second stage,the damaged building was repaired by stitching across the cracks,and tested under the same lateral *** the third stage,the twice-damaged structure was repaired once more by stitching and strengthened by twin lintel belt in steel and vertical comer reinforcement, and *** building strengthened by twin lintel belt in steel showed about 28% higher strength under lateral loading than the virgin building.

关键词： brick masonry building seismic strengthening twin lintel belt quasi-static lateral cyclic loading

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今日之远程教育

开放教育研究 2010年第3期16卷 33-39页

作者：德斯蒙德.基更赵宏 director of Irish Centre for Distance Education research and Applications

对中国远程教育领域来说,历史上有两个重要的时间点:1960年和1979年。1960年是上海电大成立,1979中国电大系统成立。我对于电大系统不断演进的研究都收录在了《远距离教育基础》、《远距离教育理论原理》《远距离教育》和《远程教育基... 详细信息

对中国远程教育领域来说,历史上有两个重要的时间点:1960年和1979年。1960年是上海电大成立,1979中国电大系统成立。我对于电大系统不断演进的研究都收录在了《远距离教育基础》、《远距离教育理论原理》《远距离教育》和《远程教育基础》等出版物中。这篇报告将首先简要回顾远程教育的缘起,再分1870-1970、1970-1990、1990-2010三个阶段回顾远程教育的发展简史。当今的远程教育作为教育培训服务中丰富而复杂的领域,可以分为五个部分:开放大学及其他大学的多媒体远程教育,电子远程教育(通常称作e-Learning),同步电子学习系统,运用校园万维网和移动学习并将对五大部分作详细分析。

关键词：多媒体远程教育《远距离教育》电子学习系统电大系统教育基础开放大学教育领域上海电大

The establishment of Macao as a special port city and ensuing debates

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Social Sciences in China 2009年第2期30卷 116-133页

作者： Wu Zhiliang[a] [a]Member of Conselho de Administraç ã o of the Macao Foundation Assistant Director of the Research Centre for Sustainable Development Strategies of the Government of the Macao Special Administrative Region

Macao was one of the earliest port cities in China to be opened to foreigners; but how, under the institutions of Ming dynasty China, it should be opened to the Portuguese, and what its character and function should be, were subjects that triggered controversy both at court and among non-officials. It was only after a lengthy process of evolution that Macao finally developed into a commercial city. The special political environment, administrative patterns and social experiences of early Macao created a unique character and tradition of ＂harmony amidst difference, and difference amidst harmony＂ that was maintained for centuries with undiminished vitality.

关键词： Macao opening as a port establishment of the city political debates historicalrole

Development of Different Strategies for the Clean-Up of Polychlorinated Biphenyls (PCBs) Congeners Using Pressurized Liquid Extraction

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Journal of Environmental Protection 2013年第1期4卷 99-107页

作者： Amal Al-Rashdan Murad I. H. Helaleh Kuwait Institute for Scientific research Deputy Director General Office for Research Safat Kuwait

The extracted fish samples (w/w) using pressurized liquid extraction (PLE) were cleaned up by applying different adsorbent materials such as: combination of acidic/ basic silica and alumina, florisil, and silica gel either alone or in combination with another sort of sorbent. Different solvents such as hexane (H), dichloromethane (DCM), with different compositions were used to elute the PCBs target compounds from the spiked fish samples. Overall the mean percentage recoveries for all PCBs congeners using PLE were ranging from 78.6% to 98.7%;from 79.4% to 91.8%;from 65.8% to 104.5% and from 82.4% to 100.9% for cases A, B, C, D and E, respectively. However, the overall mean percentage recoveries for the 13C-PCBs surrogate including: 101, 138, 153, 180 and 209 were ranging from 88.2% to 97.6%;from 79.4% to 90.2%, from 88.3% to 96.4%, from 79.8% to 90.4% and from 83.9% to 95.9%, for cases A, B, C, D and E, respectively. The limits of detection of the proposed method were varied from 0.01 to 0.28 ng/g (w/w) for different PCBs congeners. The proposed method has linear dynamic range from 21.5 ng/g to 109 ng/g. This method was applied to fish samples for the determination of the target PCBs components.

关键词： Polychlorinated Biphenyls (PCBs) Pressurized Liquid Extraction (PLE) Adsorbent Materials Gel Permeation Chromatography (GPC) Negative Chemical Ionization (NCI) Marine Sample