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Chemical Research in Chinese Universities 1997年第2期13卷 12-18页

作者： GAO Qiu ming chen jie sheng XU Ru ren Key Laboratory of Inorganic Synthesis and Preparative Chemistry Department of ChemistryJilin UniversityChangchun 130023

The present paper covers the syntheses of 1 D chain, 2 D layered and 3 D microporous aluminophosphates containing organic amines or ammonium in the presence of various amines from alcoholic systems. The rule for the crystallization of the above three families of microporous aluminophosphates was summarized and the effects of organic amine, P/Al ratio, sources of aluminum and phosphorous and temperature on the resulted structures were investigated.

关键词： Aluminophosphate template Alcoholic system Synthesis

农村寄递点选址问题的研究——以镇坪县城关镇为例

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物流工程与管理 2024年第1期46卷 1-6页

作者：陈胜杰项科晔张华丰程娟史桂芳金陵科技学院商学院江苏南京210000

民族要复兴,乡村必振兴。乡村振兴战略大力推进农业供给侧结构性改革,并将农产品产业作为扶贫工作的重要方向之一,而农村寄递物流是农产品出村进城、消费品下乡进村的重要渠道之一。因此,文中通过研究寄递点在农村的优化布局来完善农村... 详细信息

民族要复兴,乡村必振兴。乡村振兴战略大力推进农业供给侧结构性改革,并将农产品产业作为扶贫工作的重要方向之一,而农村寄递物流是农产品出村进城、消费品下乡进村的重要渠道之一。因此,文中通过研究寄递点在农村的优化布局来完善农村寄递物流体系。文中将集合覆盖模型和层次分析法相结合,考虑在合理的服务半径范围内,建立最小数量的寄递点,在节约建设成本的同时为农村寄递物流体系的研究提供一个新的思路及方向。

关键词：物流选址层次分析法集合覆盖模型农村寄递物流

Enhancing microseismic/acoustic emission source localization accuracy with an outlier-robust kernel density estimation approach

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International Journal of Mining Science and Technology 2024年第7期34卷 943-956页

作者： jie chen Huiqiong Huang Yichao Rui Yuanyuan Pu sheng Zhang Zheng Li Wenzhong Wang State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Central South UniversityChangsha 410083China Chongqing City Construction Investment Group Co. Ltd.Chongqing 400023China Coal Geological Exploration Institute of Gansu Lanzhou 730000China

Monitoring sensors in complex engineering environments often record abnormal data,leading to significant positioning *** reduce the influence of abnormal arrival times,we introduce an innovative,outlier-robust localization method that integrates kernel density estimation(KDE)with damping linear correction to enhance the precision of microseismic/acoustic emission(MS/AE)source *** approach systematically addresses abnormal arrival times through a three-step process:initial location by 4-arrival combinations,elimination of outliers based on three-dimensional KDE,and refinement using a linear correction with an adaptive damping *** validate our method through lead-breaking experiments,demonstrating over a 23%improvement in positioning accuracy with a maximum error of 9.12 mm(relative error of 15.80%)—outperforming 4 existing *** under various system errors,outlier scales,and ratios substantiate our method’s superior *** blasting experiments also confirm the practical applicability,with an average positioning error of 11.71 m(relative error of 7.59%),compared to 23.56,66.09,16.95,and 28.52 m for other *** research is significant as it enhances the robustness of MS/AE source localization when confronted with data *** also provides a practical solution for real-world engineering and safety monitoring applications.

关键词： Microseismic source/acoustic emission(MS/AE) Kernel density estimation(KDE) Damping linear correction Source location Abnormal arrivals

Hydrogen-rich surface of MoC catalysts for efficient CO_(2) hydrogenation induced by a coupled hydrogen donator

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Nano Research 2024年第8期17卷 7762-7767页

作者： Dong Xu Si-Yuan Xia Qi-Yuan Li jie-sheng chen Xin-Hao Li School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China

Direct CO_(2) hydrogenation offers an important strategy for promoting the global carbon balance,but high thermodynamic and kinetic stability of CO_(2) has restricted its applicability to only a handful of industrial ***,we introduce a proof-of-concept application of the electron-rich Pt surface to promote hydrogen donation for electron-rich MoC particles acting as hydrogen acceptors,thereby constructing hydrogen-rich surface of MoC active ***,the formed hydrogen-rich and electronrich surface could greatly decrease reaction activation energy to boost the efficient CO_(2) hydrogenation into formic acid over the MoC *** optimized MoC@NC/Pt-0.1(NC:nitrogen-doped carbon)catalyst exhibits a high turnover frequency(TOF)value of 1.2 h^(−1) at a lower temperature of 60℃and a TOF of 24.2 h^(−1) under standard reaction conditions widely used in the literature,exceeding 7 times of MoC@NC catalyst and surpassing the benchmark classical non-noble metal active center-based heterogeneous catalyst.

关键词： electron-rich Pt nanoparticles hydrogen donation hydrogen-rich MoC nanoparticles CO_(2) hydrogenation formic acid

Synthesis　and　Diffuse　Reflectance　Spectrum　of　Open－framework　Cobalt　Phosphate　DAF－2　From　Alcoholic　System

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Chemical Research in Chinese Universities 1996年第4期12卷 390-392页

作者： YU Ji-hong chen jie-sheng and XU Ru-ren(Key Laboratory of Inorganic Hydrothermal Synthesis,Department of Chemistry,Jilin University,Changchun,130023) JILIN UNIV DEPT CHEMKEY LAB INORGAN HYDROTHERMAL SYNTHCHANGCHUN 130023PEOPLES R CHINA

ＳｙｎｔｈｅｓｉｓａｎｄＤｉｆｆｕｓｅＲｅｆｌｅｃｔａｎｃｅＳｐｅｃｔｒｕｍｏｆＯｐｅｎ－ｆｒａｍｅｗｏｒｋＣｏｂａｌｔＰｈｏｓｐｈａｔｅＤＡＦ－２ＦｒｏｍＡｌｃｏｈｏｌｉｃＳｙｓｔｅｍＹＵＪｉ－ｈｏｎｇ；ＣＨＥＮＪ... 详细信息

ＳｙｎｔｈｅｓｉｓａｎｄＤｉｆｆｕｓｅＲｅｆｌｅｃｔａｎｃｅＳｐｅｃｔｒｕｍｏｆＯｐｅｎ－ｆｒａｍｅｗｏｒｋＣｏｂａｌｔＰｈｏｓｐｈａｔｅＤＡＦ－２ＦｒｏｍＡｌｃｏｈｏｌｉｃＳｙｓｔｅｍＹＵＪｉ－ｈｏｎｇ；ＣＨＥＮＪｉｅ－ｓｈｅｎｇａｎｄＸＵＲｕ－ｒ...

关键词： s:Synthesis Cobalt phosphate Alcoholic system Diffuse reflectance Spectroscopy

How Effective are Decentralized Anti-poverty Programs?

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China & World Economy 2024年第4期32卷 85-113页

作者： Shuai chen Mingda cheng jie-sheng Tan-Soo China Academy for Rural Development and School of Public Affairs Zhejiang UniversityChina Jiangxi Caitong Supply Chain Financial Group Co. Ltd.Jiangxi Financial Holding Group Co.Ltd.China Lee Kuan Yew School of Public Policy National University of SingaporeSingapore

This study examines the effectiveness of China's National Poor Counties(NPC)program,a decentralized anti-poverty initiative,by analyzing five rounds of individual-level panel data from 1988 to *** impact of two waves of the NPC program(1994 and 2001)is evaluated utilizing a panel fixed-effects regression *** results indicate substantial positive effects,with residents in NPC counties experiencing a 47 percent income increase,3.1 percent higher employment rates,and a 5.7 percent rise in household expenditure from 1988 to 2008,in comparison with non-NPC ***,the program benefited vulnerable populations,dispelling concerns about"elite capture."The study also reveals that evolving policy focus has played a pivotal role in sustaining the effects of the program over *** 1994 round prioritized low-skilled employment,and the 2001 wave emphasized productivity enhancement through skills *** findings highlight the continued efficacy of decentralized anti-povertyefforts.

关键词： decentralization elite capture National Poor Counties program poverty

UAV-assisted data collection for wireless sensor networks with dynamic working modes

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Digital Communications and Networks 2024年第3期10卷 805-812页

作者： jie chen Jianhua Tang Shien-Ming Wu School of Intelligent Engineering South China University of TechnologyGuangzhou511442China

Wireless Sensor Network(WSN)is a cornerstone of Internet of Things(IoT)and has rich application *** this work,we consider a heterogeneous WSN whose sensor nodes have a diversity in their Residual Energy(RE).In this work,to protect the sensor nodes with low RE,we investigate dynamic working modes for sensor nodes which are determined by their RE and an introduced energy ***,we employ an Unmanned Aerial Vehicle(UAV)to collect the stored data from the heterogeneous *** aim to jointly optimize the cluster head selection,energy threshold and sensor nodes’working mode to minimize the weighted sum of energy con-sumption from the WSN and UAV,subject to the data collection rate *** this end,we propose an efficient search method to search for an optimal energy threshold,and develop a penalty-based successive convex approximation algorithm to select the cluster *** we present a low-complexity iterative approach to solve the joint optimization problem and discuss the implementation *** results justify that our proposed approach is able to reduce the energy consumption of the sensor nodes with low RE significantly and also saves energy for the whole WSN.

关键词： Unmanned aerial vehicle Wireless sensor networks Cluster heads Dynamic working modes

Isomorphous Substitution of Aluminium for Gallium in a Framework Gallophosphate

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Chemical Research in Chinese Universities 1992年第2期8卷 65-70页

作者： chen jie-sheng arid XU Ru-ren (Department of Chemistry, Jilin University, Changchun, 130023)

An aluminium-substituted framework gallophosphate with occluded triethylamine was synthesized hydrothermally. 27Al MAS NMR spectroscopy indicates that only the tetrahedral coordinated gallium atoms in the gallophosphate are substituted by aluminium atoms. The substitution leads to an evident decrease in cell volume of the crystal. The differences between the original gallophosphate and the aluminium-substituted one are also found for the IR spectrum and the thermal property.

关键词： Isomorphous substitution Aluminogallophosphate Framework

The Crystallization Behavior of L-Poly(lactic acid)/Polypropylene Blends:The Acceleration for Both L-Poly(lactic acid)and Polypropylene

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Chinese Journal of Polymer Science 2024年第6期42卷 775-786页

作者： Shuang-cheng Li Wei-Jia Zhou Wen-jie Wu Jun Shao Shui-Liang chen Hao-Qing Hou sheng Xiang College of Chemistry&Chemical Engineering and Nanofiber Engineering Center of Jiangxi Province Jiangxi Normal UniversityNanchang330022China National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education Jiangxi Normal UniversityNanchang330022China Wenzhou Institute University of Chinese Academy of SciencesWenzhou325001China

For a polymer/polymer dismissible blend with two crystallizable components,the crystallization behavior of different components and the reciprocal influences between different crystals are interesting and important,but did not investigate in *** this study,the L-poly(lactic acid)/polypropylene(PLLA/PP)blends with different weight ratios were prepared by melt mixing and the crystallization behavior of the blends were *** showed that the crystalline structures of PLLA and PP were not altered by the *** the crystallization of PLLA,both the diffusion of chain segments and crystallization rate were enhanced under the existence of PP *** the crystallization of PP,its crystallization rate was depressed under the existence of amorphous PLLA molecular *** the PP crystallized from the existence of PLLA crystals,although the diffusion rate of PP was reduced by PLLA crystals,the nucleation positions were obviously enhanced,which accelerated the formation of PP *** investigation would supply more basic data for the application of PLLA/PP blend.

关键词： L-poly(lactic acid) Polypropylene Blends Crystalization behavior Crystallization acceleration

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research International 2024年第4期31卷 828-837页

作者： Gu-jun chen sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity