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Al-modified yolk-shell silica particle-supported NiMo catalysts for ultradeep hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene:Efficient accessibility of active sites and suitable acidity

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Petroleum Science 2024年第1期21卷 654-666页

作者： Ke Yu wei-min Kong Zhen Zhao Ai-Jun Duan Lian Kong Xi-Long wang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034LiaoningChina

Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective ***-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proportion)were prepared and dibenzothiophene(DBT)and 4,6-dimethyl-dibenzothiophene(4,6-DMDBT)were employed as the probes to evaluate the hydrodesulfurization(HDS)catalytic *** as-prepared AYP-x carriers and corresponding catalysts were characterized by some advanced characterizations to obtain deeper correlations between physicochemical properties and the HDS *** average pore sizes of series AYP-x supports are above 6.0 nm,which favors the mass transfer of organic *** cavity between the yolk and the shell is beneficial for the enrichment of S-containing compounds and the accessibility between reactants and active *** embedded into the silica framework could facilitate the formation of Lewis(L)and Brønsted(B)acid sites and adjust the metal-support interaction(MSI).Among all the as-synthesized catalysts,NiMo/AYP-20 catalyst shows the highest HDS *** improved HDS activity of NiMo/AYP-20 catalyst is attributed to the perfect combination of excellent structural properties of the yolk-shell mesoporous silica,enhanced acidity,moderate MSI,and good accessibility/dispersion of active components.

关键词： Al-containing yolk-shell silica particles Accessibility Acidity Metal-support interaction Hydrodesulfurization

Evaluation of the Validity of Interpretation System for the Visitors to Yuntaishan World Geopark in china

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Education for Sustainable Development in china.A Perspective on Curricula Standards and geography Textbooks

2007年海峡两岸环境与可持续发展教育研讨会

作者： wei dongying(Ph.D Candidate) wang min(Professor) college of geography,beijing normal university,beijing,china.100875

This study was conducted over a twelve-month period at Yuntaishan World Geopark centered to assess the validity of interpretation system for the visitors there and the author designed four sets of questionnaires for it,one for Chinese visitors,one for English-speaking visitors,one for the interpreters and one for management staffs of Yuntaishan World Geopark.1149 Chinese visitors,15 English-speak- ing visitors,63 interpreters and 6 management staffs completed the *** data was analyzed and compared in order to evaluate the effectiveness of the interpretation system and the attitudes of the inter- preters and management *** article mainly introduce the Chinese visitors surveys.

关键词： evaluation visitor surveys Yuntaishan World Geopark interpretation system

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Education for Sustainable Development in China:A Perspective...

Paleoenvironmental reconstruction and organic matter accumulation of the paleogene shahejie oil shale in the Zhanhua Sag, Bohai Bay Basin, Eastern china

2007年海峡两岸环境与可持续发展教育研讨会

作者： wang min wei dongying college of geography,beijing normal university

Sustainable development is a fundamental national policy in china.and Education for Sus- tainable Development(ESD)is integrated into the existing *** research examines how ESD is implemented,and presented in the curricula standards and high school geography textbooks in china. The textbooks analyzed are products of china.Map *** an overview describing the scope and na- ture of the content as it relates to sustainable development,the content and presentation of ESD in Chi- nese textbooks are *** development is a major focus of the geography textbooks for high school students and is presented in required geography Two and geography Three,and in certain elective *** Subject Outline of Environmental Education for Primary and Middle School Students is pres- ented,and it is a compilation standard for supplementary materials about Environmental Education and ESD.

关键词： Education for Sustainable Development geography textbooks curricula standards high school

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Petroleum Science 2024年第3期21卷 1552-1568页

作者： Xiao-Lin wang Xiao-min Zhu Jin Lai Xing-Yue Lin Xiang wang Yu-Shan Du Chao Huang Yu-Rui Zhu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China college of Geosciences China University of Petroleum(Beijing)Beijing102249China Shengli Oilfield SINOPECDongying257000ShandongChina

The controlling factors of organic-rich shale accumulation is essential for the exploration and development of shale oil and gas *** sedimentary environment plays a vital role in the formation of organic-rich sediments in lacustrine *** article unravels the mineralogy,geochemistry,and paleoenvironmental evolution during the deposition of the Paleogene Shahejie Formation(Es_(3)^(L)).It discusses the effects of paleoclimate,paleosalinity,paleoredox conditions,paleowater depth,and paleoproductivity on organic matter(OM)***,the OM enrichment model was *** results show that the mineralogical compositions are mainly composed of calcite(avg.40.13%),quartz(avg.21.64%)and clay minerals(avg.24.07%),accompanied by dolomite(avg.7.07%),feldspar(avg.6.36%)and pyrite(avg.2.95%).The Es_(3)^(L) shale has a high abundance of OM,with total organic carbon(TOC)ranging from 1.07%to 5.12%.The organic matter type is mainly composed of type I-II_(1) kerogen,which is generally considered a good-quality source *** source of OM is a mixture of lower bacteria,algae,and *** the early sedimentary period,the paleoclimate was dry and cold,with high salinity,intense reducibility,and relatively low *** the late sedimentary period,the climate became warmer and more *** a result,the salinity decreased to a level that was suitable for biological reproduction,and productivity increased gradually due to the input of terrigenous *** and paleoclimate determined the environment of the sedimentary period,in addition,paleoproductivity and paleoredox condition indicated the formation and preservation conditions of *** warm and humid climate,brackish water,suitable reduction conditions and high productivity are the favorable conditions for the generation and preservation of organic *** research results may have implications for the genetic mechanisms of organic matter *** will provide theoret

关键词： Elemental geochemical Paleoenvironment Organic matter accumulation Paleogene shahejie formation Zhanhua Sag Bohai Bay Basin

The Research on Relationship between Environmental Knowledge、Attitude to Environment and Anticipated Environmental Behavior of Primary and Middle School Students in china

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The Research on Relationship between Environmental Knowledge...

(3, 1)^(*)-choosability of plane graphs without adjacent single cycles

2007年海峡两岸环境与可持续发展教育研讨会

作者： wang min wei dongying beijing normal university,china

According to the result of a questionnaire survey for 15412 Chinese students of middle schools and primary schools in ten provinces and cities,the article appraises the environmental awareness of Chi- nese students of middle schools and primary schools in accordance with the appraisal models. Comprehensive score of middle school students is 72.45,but that of primary students is 75.59,which is higher than the *** further research about the relationship between every element of environ- mental awareness,the conclusion was drawn that the model of environmental awareness is"knowledge- attitude-behavior"for primary students and is"attitude-behavior"for middle school students.

关键词： china Primary students and middle school students Environmental awareness Model Note:"The students"means Chinese primary students and middle school students in the article

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Frontiers of Mathematics in china 2024年第2期19卷 101-115页

作者： Jufeng ZHANG min CHEN Yiqiao wang college of Mathematics and Computer Science Zhejiang Normal UniversityJinhua 321004China School of Management Beijing University of Chinese MedicineBeijing 100029China

Given a list assignment of L to graph G,assign a list L(υ)of colors to each υ∈V(G).An(L,d)^(*)-coloring is a mapping π that assigns a color π(υ)∈L(υ)to each vertex υ∈V(G)such that at most d neighbors of υ receive the color υ.If there exists an(L,d)^(*)-coloring for every list assignment L with|L(υ)|≥k for all υ∈ V(G),then G is called to be(k,d)^(*)-*** this paper,we prove every planar graph G without adjacent k-cycles is(3,1)^(*)-choosable,where k ∈{3,4,5}.

关键词： Plane graph improper list coloring (k,d)^(*)-choosable cycle

Hollow Multishelled Structure: Synthesis Chemistry and Application

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Chemical Research in Chinese Universities 2024年第3期40卷 346-393页

作者： MAO Dan wang Chao LI wei ZHOU Liang LIU Jian ZHENG Zjian ZHAO Yong CAO An-min wang Shutao HUANG Jiaxing HUO Fengwei CHEN Hongyu MAI Liqiang YU Ranbo wang Lianzhou LU Yunfeng YU Chengzhong YANG Qihua YANG Zhenzhong ZENG Hua Chun ZHAO Hujun TANG Zhiyong ZHAO Dongyuan wang Dan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChineseAcademy of SciencesBeijing 100190P.R.China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese Academy of SciencesBejing 100190P.R.China School of Fashion and Textiles The Hong Kong Polytechnic UniversityHong Kong SARP.R.China Department of Chemistry Fudan UniversityShanghai 200433P.R.China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070P.R.China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023P.R.China School of Chemistry Beihang UniversityBejing 100191P.R.China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190P.R.China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190P.R.China School of Engineering Westlake UniversityHangzhou 310024P.R.China School of Flexible Electronics(Future Technologies) Nanjing Tech UniversityNanjing 211816P.R.China School of Science Westlake UniversityHangzhou 310024P.R.China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070P.R.China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083P.R.China School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnology The University of QueenslandBrisbaneQueensland 4072Australia college of Life Science and Technology Bejing University of Chemical TechnologyBejing 100029P.R.China School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200241P.R.China college of Life Sciences Zhejiang Normal UniversityJinhua 321004P.R.China Department of Chemical Engineering Tsinghua UniversityBeijing 100

Hollow multishelled structure(HoMS),a promising and complex multifunctional structural system,features at least two shells that are separated by internal *** unique structure endows it with numerous advantages including low density,high loading capacity,large specific surface area,facilitated mass transport,and multiple spatial confinement *** the past twenty years,benefiting from the booming development of synthesis methods,various HoMS materials have been prepared and show promising applications in diverse areas.

关键词： Hollow multishelled structure Synthesis chemistry Energy storage Catalysis Electromagnetic wave absorption Drug delivery Sensor

EXPERIMENTAL INVESTIGATION OF CHARACTERISTIC FREQUENCY IN UNSTEADY HYDRAULIC BEHAVIOUR OF A LARGE HYDRAULIC TURBINE

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Journal of Hydrodynamics 2009年第1期21卷 12-19页

作者： wang Fu-jun LI Xiao-qin MA Jia-mei YANG min ZHU Yu-liang college of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China beijing Huake Tongan Monitoring Technology Co. Ltd. Beijing 100037 China

The features of unsteady flow such as pressure variation and fluctuation in a large hydraulic turbine usually lead to the instability of operation. This article reports the recent in site investigation concerning the characteristic frequencies in pressure fluctuation, shaft torsional oscillation and structural vibration of a prototype 700 MW Francis turbine unit. The investigation was carried out for a wide load range of 200 MW-700 MW in the condition of water head 57 m-90 m. An extensive analysis of both time-history and frequency data of these unsteady hydraulic behaviours was conducted. It was observed that the pressure fluctuation in a draft tube is stronger than that in upstream flow passage. The low frequency with about one third of rotation frequency is dominative for the pressure fluctuation in part load range. Also the unsteady features of vibration of head cover and torsional oscillation of shaft exhibited the similar features. Numerical analysis showed that the vibration and oscillation are caused by vortex rope in the draft tube. In addition, a strong vibration with special characteristic frequency was observed for the head cover in middle load range. The pressure fluctuation in the draft tube with the same frequency was also recorded. Because this special vibration has appeared in the designed normal running condition, it should be avoided by carefully allocating power load in the future operation.

关键词： hydraulic turbine part load swirling flow unsteady behaviour characteristic frequency power load allocation

Analysis of Neutron Double-Differential Cross Section of n+14N at 14.2 MeV

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Communications in Theoretical Physics 2005年第7期44卷 128-132页

作者： YAN Yu--Liang DUAN Jun--Feng SUN Xiao--Jun wang Ji--min ZHANG Jing--Shang china.Institute of Atomic Energy, P. O. Box 275(41), beijing 102413, china.college of Physics and Information Technology, Guangxi normal university, Guilin 541004, china china.Institute of Atomic Energy P.O. Box 275(41) Beijing 102413 China

By using a new reaction model for light nuclei,the double-differential cross section of n+14N reactions atE_n=14.2 MeV has been *** the case of n+（14）N reactions,the reaction mechanism is cery complex,there areover one hundred opened partial reaction channels even at incident energy En=14.2 *** this paper the openedreaction channels are listed in detail. With LUNF code the model calculation is performed to analyze the double-differential cross sections of total outgoing neutron. The calculated results agree fairly with the experimenal *** indicate that the pre-equilibrium mechanism mechanism dominates the whole reation processes,and the recoil effect in lightnuclear reactions is essentially important.5He emission has been considered,but it is only a small contribution to thedonble-differential cross section at incident energy En=14.2 MeV.

关键词： light nucleus reaction double-differential cross section