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有机液相储氢载体脱氢催化剂的制备及催化性能

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中国石油大学学报（自然科学版） 2024年第4期48卷 215-223页

作者：赵世栋周路阳商红岩徐永强张洪伟林旭锋中国石油大学(华东)重质油国家重点实验室山东青岛266580

利用等体积浸渍法制备一系列不同Sn负载量的Pt-Sn/Al_(2)O_(3)催化剂以及Pt/活性炭、Pt/Al_(2)O_(3)单金属催化剂,采用X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)、氨气程序升温脱附(NH_(3)-TPD)、低温N_(2)吸附手段,对所制备的催化... 详细信息

利用等体积浸渍法制备一系列不同Sn负载量的Pt-Sn/Al_(2)O_(3)催化剂以及Pt/活性炭、Pt/Al_(2)O_(3)单金属催化剂,采用X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)、氨气程序升温脱附(NH_(3)-TPD)、低温N_(2)吸附手段,对所制备的催化剂进行表征。使用固定床反应器,分别以甲基环己烷和12H-苄基甲苯为原料,对所制备的催化剂进行脱氢反应性能评价。结果表明:氧化铝载体催化剂酸量、酸强度均高于活性炭载体催化剂,但氧化铝载体Pt-Sn催化剂在负载Sn后,中强酸酸性位强度得到不同程度的减弱;对甲基环己烷-甲苯储氢体系筛选出脱氢效果最优的0.5Pt-0.2Sn/Al_(2)O_(3)催化剂(含量为质量分数,%),甲苯选择性超过99%,脱氢率高于97%;60 d长周期运行后甲基环己烷脱氢转化率超过98.5%,甲苯选择性高于99%,催化剂未出现失活现象。

关键词： Pt催化剂 Pt-Sn催化剂脱氢苄基甲苯甲基环己烷

经肛全直肠系膜切除术易损伤区域及术中处理策略

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结直肠肛门外科 2024年第2期30卷 159-162页

作者：赵世栋叶颖江申占龙北京大学人民医院胃肠外科北京100044

经肛全直肠系膜切除术经过十余年的发展和实践,凭借其在低位直肠癌根治术中良好的手术视野,得到了越来越多结直肠外科医师的认可。但由于经肛全直肠系膜切除术是“由尾向头”的操作视角,结直肠外科医师需要正确认识相关的解剖层面及标志... 详细信息

经肛全直肠系膜切除术经过十余年的发展和实践,凭借其在低位直肠癌根治术中良好的手术视野,得到了越来越多结直肠外科医师的认可。但由于经肛全直肠系膜切除术是“由尾向头”的操作视角,结直肠外科医师需要正确认识相关的解剖层面及标志,以便获得更高的手术质量。本文围绕肛门括约肌、骶前静脉、神经血管束、盆丛后支及男性尿道这5个经肛全直肠系膜切除术易损伤区域以及相关操作要点进行阐述,并提出术中处理策略。

关键词：经肛全直肠系膜切除术 “由尾向头” 易损伤区域操作要点处理策略

Simulating　sensitivities　of　Changbai　Mountain　forests　to　potential　climate　change

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Journal of Environmental Sciences 1996年第3期8卷 354-366页

作者： Yan Xiaodong zhao shidong (Institute of Applied Ecology. Chinese Academy of Sciences,Shenyang 110015, China) Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110015 China

Changbai Mt. forest in the northeastern China is both a very important timber resource of China and one of the most typical and less disturbed temperate mixed evergreen coniferous-deciduous forest in the *** this paper, NEWCOP. a gap class model of forest growth and succession was proposed to simulate the sensitivity of the forest in Changbai Mountain to elevate CO_2. warmer temperature and precipitation change. NEWCOP was tested on long term simulation behaviors and short term fitting ability to field data. About the response of forests of Changbai Mountain to possible climate change, NEWCOP suggested that forest landscape go up within long term and forest biomass comes down within short term because of dieback of forest trees.

关键词： gap model climate change forests China.

Simultaneous formation of a C/N-TiO_2 hollow photocatalyst with efficient photocatalytic performance and recyclability

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Chinese Journal of Catalysis 2019年第5期40卷 765-775页

作者： Yingguan Xiao Xiaodong Sun linyu Li Juanrong Chen shidong zhao Caiguo Jiang a Luyao Yang Li Cheng Shunsheng Cao Research School of Polymer Materials School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 Jiangsu China School of Environment and Safety Engineering Jiangsu University Zhenjiang 212013 Jiangsu China

Herein,we report a unique approach towards the preparation of C-modified and N-doped TiO2 hollow spheres(C/N-TiO2).TEM,SEM,and XPS analyses were used to confirm that the carbon and nitrogen co-decorated TiO2 photocatalyst was ***-decoration improves the visible-light absorption and speeds up the separation of the photo-generated electron-hole pairs.C/N-TiO2 not only narrows the band gap of TiO2,but also exhibits excellent photocatalytic activity for the degradation of tetracycline and tetracycline *** addition,the C/N-TiO2 photocatalyst shows excellent recyclability for water decontamination,making it a promising candidate to purify aquatic contaminants.

关键词： Simultaneous synthesis C/N-doped TiO2 Hollow sphere Tetracycline Photocatalysis

Effect of Polyvinyl Alcohol in Inner Aqueous Phase on Stability of Millimeter-scale Capsules

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 506-511页

作者：黄乐平 LI shidong ZHANG Jiabei PAN Chenchen 赵瑾朝 School of Material Science and Engineering Wuhan Textile UniversityWuhan 430200China Hubei Provincial Engineering Laboratory for Clean Production and High Value Utilization of Bio-Based Textile Materials Wuhan Textile UniversityWuhan 430200China

The millimeter-scale capsules with controllable morphology,ultra-low permeability and excellent mechanical stability were fabricated by *** of inner phase was adjusted to control the morphology and properties of the *** detail,as the concentration of polyvinyl alcohol(PVA)increased from 0 to 8% in the inner phase of the capsules,the diameter of capsules decreased from 3.33 ± 0.01mm to 2.97 ± 0.01 mm,the shell thickness of capsules decreased from 0.183 ± 0.004 mm to 0.155 ± 0.003 *** the capsules had round shape and high ***,the capsules with 2% PVA in the inner phase had remarkably decreased water permeability and good morphological ***,the end-time of water losing of the capsules was up to 49 days,while the dehydrated capsules maintained spherical appearance,and crushing force of the capsules was up to 13.73 ± 0.79 N,which ensured stability during processing and *** research provides a new strategy for stable encapsulation of small molecules.

关键词： capsule millimeter-scale millifluidics polyvinyl alcohol viscosity

Tuning Structural and Electronic Configuration of FeN_(4) via External S for Enhanced Oxygen Reduction Reaction

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Energy & Environmental Materials 2024年第2期7卷 93-101页

作者： shidong Li Lixue Xia Jiantao Li Zhuo Chen Wei Zhang Jiexin Zhu Ruohan Yu Fang Liu Sungsik Lee Yan zhao Liang Zhou Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Foshan 528200China Chemical Sciences and Engineering Division Argonne National Laboratory9700 South Cass AvenueLemontIL 60439USA NRC(Nanostructure Research Centre) Wuhan University of TechnologyWuhan 430070China X-ray Science Division Advanced Photon SourcesArgonne National Laboratory9700 South CassAvenueLemontIL 60439USA State Key Laboratory of Silicate Materials for Architectures International School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China Hubei Longzhong Laboratory Xiangyang 441000China

The Fe-N-C material represents an attractive oxygen reduction reaction electrocatalyst,and the FeN_(4)moiety has been identified as a very competitive catalytic active *** tuning of the coordination structure of FeN_(4)has an essential impact on the catalytic ***,we construct a sulfur-modified Fe-N-C catalyst with controllable local coordination environment,where the Fe is coordinated with four in-plane N and an axial external *** external S atom affects not only the electron distribution but also the spin state of Fe in the FeN_(4)active *** appearance of higher valence states and spin states for Fe demonstrates the increase in unpaired *** the above characteristics,the adsorption and desorption of the reactants at FeN_(4)active sites are optimized,thus promoting the oxygen reduction reaction *** work explores the key point in electronic configuration and coordination environment tuning of FeN_(4)through S doping and provides new insight into the construction of M-N-C-based oxygen reduction reaction catalysts.

关键词： coordination structure electronic configuration FeN_(4)moiety oxygen reduction reaction sulfur doping

DISTRIBUTION PATTERNS OF LEAF AREA INDEX FOR MAJOR CONIFEROUS FOREST TYPES IN CHINA

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Journal of Geographical Sciences 1997年第4期7卷 61-73页

作者： Luo Tianxiang Li Wenhua zhao shidong Commission for Integrated Survey of Natural Resources, CAS, Beijing 100101 The People’s Republic of China

Leaf area index (LAI) of natural vegetation is recognized as the most important variable for measuring vegetation structure over large areas, and for relating it to energy and mass exchange, which has been successfully estimated from satellite resolution sensors. In this paper, according to the statistical analysis based on a lot of forest plots, the mathematical models of LAI distribution patterns in the hydro thermal spaces for five coniferous forest types in China were established. For the cold temperate larch forests growing in the dry and cold climate, their LAI increases with the increasing of warm index and precipitation in the way of hyperbolic quadratic surface. For the cold temperate spruce fir forests and temperate Pinus tabulaeformis forests, their LAI is negatively related to the annual mean air temperature in the way of the natural exponential curve, in order to adapt to the water oppressed environments. For the subtropical Pinus massoniana forests and Cunninghamia lanceolata forests growing in the warm and moist climate, their LAI is related to the annual mean air temperature in the way of the parabolic quadratic curve.

关键词： leaf area index hydro thermal space distribution pattern.

Recent Advances and Challenges in Ecosystem Service Research

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Journal of Resources and Ecology 2014年第1期5卷 82-90页

作者：张永民赵士洞郭荣朝河南财经政法大学资源与环境学院郑州450046 中国科学院地理科学与资源研究所北京100101

Despite its recency as a research area, ecosystem service research has developed over the last decade into a signiifcant area of science. In this paper we review recent advances and challenges in ecosystem service research. Our review ifnds that （i） Ecosystem services are ubiquitous in biosphere. But they are treated differently among scientific communities. In order for the concept of ecosystem services to make a large and meaningful contribution to conservation and human wel-being, it needs to be clearly deifned and put into a framework so that it is both ift for a given research purpose and operational for management decisions. In addition, there is not one classiifcation scheme for al purposes. Ecosystem services should be classiifed based upon both the characteristics of ecosystem services of interest and a context for which the concept of ecosystem services is being mobilized. （i ） As sources of human wel-being, ecosystem services have several key ecological and economic characteristics such as complexity, spatial scales, public-private goods aspect and benefit dependence. Understanding these characteristics is a prerequisite for measuring, modeling, valuing and managing ecosystem services. （iii） Human demands for ecosystem services and the supply and use of them are three necessary linkages between ecosystems and human well-being. They are of great importance to such vital issues as ecological conservation and social equity. In most cases, integrated studies involving multi-disciplines, multi-sectors and multi-districts on those three linkages should be carried out to support sound ecosystem service management decisions. And （iv） ecosystem services have multiple value attributes including utilitarian values and non-utilitarian values. In the processes of making decisions concerning the use of ecosystem services, al kinds of values are usual y played out on a common and not always level playing ifeld. They intersect and interact in various ways, and may comple

关键词： ecosystem services human wel-being ecosystem service research advances and chal enges

Land use change and its ecological effect in Qian’an County of Jilin Province

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Journal of Geographical Sciences 2003年第4期13卷 423-428页

作者： ZHONGLinsheng ZHANGYongmin zhaoshidong KarlE.Rvavec Inst.ofGeographicSciencesandNaturalResourcesResearch CASBeijing100101China DepartmentofGeography UniversityofMinnesotaMN55455USA

Based on GIS and statistical methods, with the help of searching historical literatures and calculating the landscape indices, the land use changes of Qian'an County in both spatial and temporal aspects from 1945 to 1996 has been analyzed in this paper. And the driving forces of land use changes and their ecological effects are discussed too. The main findings of this study are as follows: (1) Land use changed greatly in Qian'an during 1945-1996, characterized by a decrease in grassland, wetland and water bodies, and an increase in cultivated land, saline-alkali land, and the land for housing and other construction purposes. Grassland decreased by 175,828.66 ha, and cultivated land increased by 102,137.23 ha over the half century. Accordingly, the main landscape type changed from a steppe landscape to a managed agricultural ecosystem. (2) Results of correlation analysis show that the land use change in the study area was mainly driven by the socioeconomic factors. (3) The ecological effects of land use change in the area are characterized by serious salinization, degression of soil fertility and the weakening of landscape suitability.

关键词： land use change ecological effect land degradation Qian'an County