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Influence of rare earth promoters on the performance of Ni/Mg(Al)O catalysts for hydrogenation and steam reforming of toluene

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Rare Metals 2009年第6期28卷 582-589页

作者： ZHANG Yuwen CHENG Hongwei LU Xionggang DING Weizhong ZHOU Guozhi Shanghai Key Laboratory of Modem Metallurgy and Materials Processing School of Materials Science and Engineering Shanghai University Shanghai 200072 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

CeO2., La2.3-, and ZrO2.promoted Ni/Mg（Al）O catalysts synthesized by hydrotalcite-type precursors have been investigated with respect to catalytic activity and carbon formation in the hydrogenation and steam reforming of toluene as a model tar compound. X-ray diffraction （XRD）, Brunauer-Emmett-Teller （BET） specific surface area and Hz-temperature programmed reduction （TPR） were used to observe the characteristics of the prepared catalysts. The carbon formation and its amount on the used catalysts were examined by transmission electron microscope （TEM）, scanning electron microscope （SEM） and thermogravimetric （TG）. The trend of catalytic activity as derived from the experimental results followed the order： Ni-Ce〉Ni-La〉Ni-Zr〉Ni. The catalyst modified with CeO2.exhibited the highest catalytic performance and had good carbon resistance in the hydrogenation and steam reforming of toluene. A toluene conversion of 96.8%, a CH4 yield of 45.2. and a CO yield of 50.4% have been achieved. The addition of promoters led to better dispersion of nickel species and higher interaction nickel-support, which were favorable for increasing the catalytic activity and effectively preventing carbon formation.

关键词： hydrogen production hydrogenation rare earth hydrotalcite

Parallel algorithm for real-time contouring from grid DEM on modern GPUs

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Science china(Technological Sciences) 2010年第S1期53卷 33-37页

作者： CHEN Zhuo,SHEN Lei,ZHAO YanQing & YANG ChongJun State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University,beijing 100101,{2. 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

A real-time algorithm for constructing contour maps from grid DEM data is *** runs completely within the programmable 3D visualization *** interpolation is paralleled by rasterizer units in the graphics card,and contour line extraction is paralleled by pixel *** each frame of the rendering,we first make an elevation gradient map out of original terrain vertex data,then figure out the final contour lines with image-space processing,and directly blend the results on the original scene to obtain a final scene with contour map using *** implement this method in our global 3D-digitalearth system with Direct3D?9.0c API and tested on some consumer level PC *** arbitrary scene with certain LOD level,the process takes less than 10 ms,giving topologically correct,anti-aliased contour lines.

关键词： contour map contour lines paralleled computing 3D terrain GPU digital earth

1970～2.10年国际比较教育研究之演进——基于科学知识图谱方法的实证分析

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外国教育研究 2011年第9期38卷 37-44,49页

作者：王素邹俊伟中央教育科学研究所国际比较教育研究中心北京100088

1970～2.10年国际比较教育研究呈现出以下主要特点:1)比较教育的研究前沿基本按时期顺序演变,依次包括受社会科学理论、实证方法和人力资本理论影响的2.世纪六七十年代;受平等观念、世界体系理论和教育实践影响的2.世纪八九十年代;受全... 详细信息

1970～2.10年国际比较教育研究呈现出以下主要特点:1)比较教育的研究前沿基本按时期顺序演变,依次包括受社会科学理论、实证方法和人力资本理论影响的2.世纪六七十年代;受平等观念、世界体系理论和教育实践影响的2.世纪八九十年代;受全球化理论、知识经济理论和新市民社会理论影响的"2.00后"。2.比较教育的研究热点随着时代发展而不断变化,而且与当时的社会变革和理论发展关系极为密切。3)比较教育的知识基础在2.世纪60年代至80年代逐渐趋于稳定并基本成熟,研究方法形成了以教育学、社会学、经济学为主,部分与应用心理学、哲学和历史学相关的理论和方法的格局。4)2.世纪70年代至今,国际组织在比较教育发展过程中始终扮演着重要角色。

关键词：国际比较教育研究前沿知识基础文献计量方法

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最小隶属度偏差法应用于路网规划方案评价

系统工程学报 2004年第3期19卷 317-320页

作者：奚宽武覃增雄石建军徐永利北京工业大学交通研究中心北京100022 中国公路工程咨询监理总公司北京100101 山东省路桥集团有限公司山东济南250021

考虑到公路网规划方案评价体系的多因素和多目标性,文章提出用模糊多目标系统最优决策法———最小隶属度偏差法进行路网规划方案的综合评价,该方法在处理模糊性的评价指标方面具有明显优势.随后给出了各评价指标无量纲化的标准函数,并... 详细信息

考虑到公路网规划方案评价体系的多因素和多目标性,文章提出用模糊多目标系统最优决策法———最小隶属度偏差法进行路网规划方案的综合评价,该方法在处理模糊性的评价指标方面具有明显优势.随后给出了各评价指标无量纲化的标准函数,并对适中型指标和区间型指标的无量纲化标准函数给予了重点介绍.最后结合工程实际,对提出方法的实用性进行了验证.

关键词：综合评价隶属度最优解

Digital Cancellation Scheme and Hardware Implementation for High-Order Passive Intermodulation Interference Based on Hammerstein Model

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china Communications 2019年第9期16卷 165-176页

作者： Xiaqing Miao Lu Tian School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China china Academy of Electronics and Information Technology Beijing 100041China

Passive intermodulation(PIM)interference urgently needs to be solved in the satellite communication system,owing to degrading the whole *** research contributions to the cancellation method for PIM were focused on the analog domain,however,the PIM distortion cannot be eliminated completely with the ***,some researchers attempt to tackle the problem through digital signal processing,nevertheless,the proposed methods were not suitable for the practical satellite communication *** this paper,we present a general scheme for the adaptive feedforward PIM ***-order PIM signals at baseband are estimated by modeling the PIM distortion with Hammerstein model in the digital *** on the reconstructed PIM signal,we adopt the least mean square algorithm to adaptively mitigate the PIM interference for tracking the variation of *** time and frequency synchronization of PIM are based on the correlation of the peak of received signals with the corresponding reconstructed PIM *** experimental results show that the scheme can effectively cancel the PIM interference,and achieve an interference suppression gain more than 2.dB.

关键词： satellite communication passiveintermodulation interference digital cancellation Hammerstein model

Does the F10.7 index correctly describe solar EUV flux during the deep solar minimum of 2.07-2.09?

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Does the F10.7 index correctly describe solar EUV flux durin...

Design and Application of an Open Structure and Network-based CCSDS Data Transmission Test-bed

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Yiding Chen,Libo Liu,and Weixing Wan 1 beijing National Observatory of Space Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing,{2.. 2.State Key Laboratory of Space Weather,center for Space Science and Applied research,Chinese Academy of Sciences,beijing,{2..

[1]This paper shows that the relationship between solar EUV flux and the F index during the extended solar minimum(Smin) of 2.07-2.09 is different from that in the previous *** difference is also seen in the relationship between fF and *** collected SOHO/SEM EUV observations and the F index,through June 2.10,to investigate solar irradiance in the recent *** find that,owing to F and solar EUV flux decreased from the last Smin to the recent one with different amplitudes(larger in EUV flux),EUV flux is significantly lower in the recent Smin than in the last one for the same ***,F does not describe solar EUV irradiance in the recent Smin as it did in the last *** caused remarkable responses in ionospheric fF,For the same F,fF in the recent Smin is lower than that in the last one;further,it is also lower than that in other previous ***,F is not an ideal indicator of fF during the recent Smin,which implies that F is not an ideal proxy for solar EUV irradiance during this period,although it has been adequate during previous *** irradiance models and ionospheric models will need to take this into account for solar cycle investigations.

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来源： cnki会议评论

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Design and Application of an Open Structure and Network-base...

基础教育课程改革的反思与评价——第四次全国课程学术研讨会综述

第一届国际测量仪器与测试自动化学术会议

作者： Yao Xiujuan Bian Chunjiang BaiXianlin Wang Chunmei (center for Space Science and Applied research of Chinese Academy of Sciences {2. 100080 china)

＜正＞In this paper, on the basis of introduction of CCSDS AOS （Advanced Orbiting System）, an open and network-based test-bed is presented, including its design methodology and application of data transmission in CCSDS AOS. The test-bed is built in ETX open structure with Linux OS and designed modularly. It is used for simulating, testing and validating the CCSDS AOS data transmission service and other ATE of space payloads and telecommunication system as well.

关键词： Open platform network based test-bed CCSDS.

来源： cnki会议评论

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课程．教材．教法 2004年第8期24卷 3-10页

作者： General Secretary of National Curriculum Professional Committee (Curriculum and Teaching Material research Institute, beijing 100009, {2.) 全国课程专业委员会秘书处课程教材研究所北京 100009

为了积极推动、配合我国新一轮基础教育课程改革，加强全国课程专业委员会的学术研讨与交流，中国教育学会教育学分会课程专业委员会特主办第四次全国课程学术研讨会。会议的主题是：“基础教育课程改革的反思和评价”。与会代表主要研... 详细信息

为了积极推动、配合我国新一轮基础教育课程改革，加强全国课程专业委员会的学术研讨与交流，中国教育学会教育学分会课程专业委员会特主办第四次全国课程学术研讨会。会议的主题是：“基础教育课程改革的反思和评价”。与会代表主要研讨五项议题：新基础教育课程改革的理论创新和反思；新课程的实施与评价；地方课程、校本课程、综合实践活动课程的开发与反思；新课程与教师专业发展；基础教育课程改革的政策分析与课程管理的反思。会议取得了丰硕的成果。

关键词：基础教育课程课程改革反思与评价

A Study on the Impacts of Climate Change on the Distribution of Pinus tabulaeformis in china

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Chinese Forestry Science and Technology 2002年第4期1卷 55-61页

作者： XU Deying YAN Hongresearch Institute of Forest Ecology. Environment and Protection. CAF. beijing 100091. {2. research Institute of Forestry. CAF. beijing 100091. {2.

A special interpolation program GREEN has been developed to determine the climatic parameters for the distribution region of Chinese pine (Pinus tabulaeformis Carr.) based on the researches on the distribution of the tree species. The central region, which is the most suitable distribution region, and potential distribution region of the species under current climatic conditions were mapped using a Geographic Information System IDRISI. According to the averaged predictions by 5 GCMs for 2.30, a projecti...

关键词： climate change tree species Chinese pine geographic distribution.