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Chinese Journal of Chemistry 2013年第10期31卷 1250-1256页

作者： Yueqin cai Gonghua song Xiao Chen School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai 200237 China Shanghai Key Laboratory of Chemical Biology Institute of Pesticides & Pharmaceuticals East China University of Science and Technology Shanghai 200237 China

The coordination mode of IL-supported diols used as phosphine-free ligands for palladium catalyzed Heck reaction has been investigated by tuning their compositions. The difference in coordination of these IL-supported diols with metal Pd in Heck reaction was related to the changes of the cation rings, leading to the different activities of Pd catalyst in the reaction. The experimental results indicated that the activities of Pd catalyst were affected mainly by n-electron density of the cation rings. Compared to pyridinium and piperidinium cations, imidazolium cations showed the best coordination to metal Pd. In the meantime, C-2 hydrogen and the length of alkyl side chains had impacts on the coordination as well.

关键词： homogeneous catalysis acylation Heck reaction phosphine-free ligands

On the Quasi-Concavity of Equipment Sharing Games with Perishable Raw Materials

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Journal of Systems Science and Systems Engineering 2021年第6期30卷 649-666页

作者： Jun Li Xiaoqiang cai Yinlian Zeng Hairong feng School of Economics and Management Southwest Jiaotong UniversityChengdu 610031China Shenzhen Research Institute of Big Data Shenzhen 518172China School of Data Science The Chinese University of Hong KongShenzhenShenzhen 518172China School of Business Southern University of Science and TechnologyShenzhen 518055China School of Business Sichuan Normal UniversityChengdu 610101China

We study the equipment sharing problem where a group of food&beverage companies share the same equipment of a contractor and wish to have their processing tasks coordinated such that the total cost is *** raw materials to be processed are perishable,which incur a decay cost as time *** key issue of this equipment sharing problem is how to allocate the total cost among the *** apply cooperative game theory to tackle this issue and formulate the problem as an equipment sharing ***,we study the 1-equipment sharing game in which all participants share one *** show that the 1-equipment sharing game is quasi-concave when the fixed operation cost is larger than a certain *** then discuss the special case where the processing time for all participants is *** this case,we further investigate the properties of the 1-equipment sharing game and the multi-equipment sharing *** identify the conditions under which the Shapely value and the T-value can be easily calculated for the 1-equipment and multi-equipment sharing games.

关键词： Equipment sharing quasi-concave games perishable raw materials decay loss

Direct Visual Evidence for Neutral and Charged Hexaphyrin Aromaticity with and without Keto-Defect

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Chinese Journal of Chemical Physics 2012年第5期25卷 563-570,I0003页

作者： Shan Zhang Peng song Sha Wang Yu-ling Chu Yuan-zuo Li Zhong Yang Yong Ding feng-cai Ma Department of Physics Liaoning UniversityShenyang 110036China Physical and Electronic and Information Engineering Institute Chifeng UniversityChifeng 024001China College of Science Northeast Forestry UniversityHarbin 150040China

We use density functional theory and time-dependent together with a set of extensive mul- tidimensional visualization techniques to characterize the influence of keto effect on charge distribution at ground state and electronic transitions for neutral and charged hexaphyrin aromaticity with and without keto-defect. It is found that the aromaticity is the key fac- tor to influence the ground state Mulliken charges distribution properties, other than the meso-aryl-substituted effect. But with the enhancement of the keto-defect, the distribution changes of Mulliken charges on the hexaphyrin groups are larger than those on the pentaflu- orophenyl substituted groups, following with the aromaticity changes from nonaromatic to aromatic. Furthermore, through characterizing by transition density and charge difference density, direct visual evidence for neutral and charged aromaticity with and without keto- defect can be clearly derived, and the ability of charge transfer between units of monoradical （nonaromaticity） and singlet biradical （aromaticity） forms is much stronger than that of neutral forms.

关键词： Aromaticity Keto-defect Porphyrin Charge difference density Transitiondensity

High‑Entropy Electrode Materials:Synthesis,Properties and Outlook

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Nano-Micro Letters 2025年第1期17卷 472-506页

作者： Dongxiao Li Chang Liu Shusheng Tao Jieming cai Biao Zhong Jie Li Wentao Deng Hongshuai Hou Guoqiang Zou Xiaobo Ji College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083People’s Republic of China School of Chemistry and Chemical Engineering Hunan Institute of EngineeringXiangtan 411104People’s Republic of China

High-entropy materials represent a new category of high-performance materials,first proposed in 2004 and extensively investigated by researchers over the past two *** definition of high-entropy materials has continuously *** the last ten years,the discovery of an increasing number of high-entropy materials has led to significant advancements in their utilization in energy storage,electrocatalysis,and related domains,accompanied by a rise in techniques for fabricating high-entropy electrode ***,the research emphasis has shifted from solely improving the performance of high-entropy materials toward exploring their reaction mechanisms and adopting cleaner preparation ***,the current definition of high-entropy materials remains relatively vague,and the preparation method of high-entropy materials is based on the preparation method of single metal/low-or medium-entropy *** should be noted that not all methods applicable to single metal/low-or medium-entropy materials can be directly applied to high-entropy *** this review,the definition and development of high-entropy materials are briefly ***,the classification of high-entropy electrode materials is presented,followed by a discussion of their applications in energy storage and catalysis from the perspective of synthesis ***,an evaluation of the advantages and disadvantages of various synthesis methods in the production process of different high-entropy materials is provided,along with a proposal for potential future development directions for high-entropy materials.

关键词： High-entropy Energy storage Electrode materials

Soft Tissue Myoepithelioma in Children:A Rare Case Report of the Mediastinum and a Review of the Literature

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Biomedical and Environmental Sciences 2022年第9期35卷 867-871页

作者： DU Hong Mei cai Wei song Department of Oncology Shengjing Hospital of China Medical UniversityShenyang 110004LiaoningChina

Myoepithelioma(ME)is a rare tumor composed of myoepithelial cells that usually surround glandular *** differ from mixed tumors as they present minimal or no ductal differentiation^([1]).MEs can originate from soft tis... 详细信息

关键词： Myo epithel Rare

Measures for controlling large deformations of underground caverns under high in-situ stress condition--A case study of JinpingⅠhydropower station

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Journal of Rock Mechanics and Geotechnical Engineering 2016年第5期8卷 605-618页

作者： Shengwu song Xuemin feng Chenggang Liao Dewen cai Zhongxu Liu Yunhao Yang PowerChina Chengdu Engineering Corporation Limited Chengdu610072China

The Jinping I hydropower station is a huge water conservancy project consisting of the highest concrete arch dam to date in the world and a highly complex and large underground powerhouse cavern. It is located on the right bank with extremely high in-situ stress and a few discontinuities observed in surrounding rock masses. The problems of rock mass deformation and failure result in considerable challenges related to project design and construction and have raised a wide range of concerns in the fields of rock mechanics and engineering. During the excavation of underground caverns, high in-situ stress and relatively low rock mass strength in combination with large excavation dimensions lead to large deformation of the surrounding rock mass and support. Existing experiences in excavation and support cannot deal with the large deformation of rock mass effectively, and further studies are needed. In this paper, the geological conditions, layout of caverns, and design of excavation and support are first introduced, and then detailed analyses of deformation and failure characteristics of rocks are presented. Based on this, the mechanisms of deformation and failure are discussed, and the support adjustments for controlling rock large deformation and subsequent excavation procedures are proposed. Finally, the effectiveness of support and excavation adjustments to maintain the stability of the rock mass is verified. The measures for controlling the large deformation of surrounding rocks enrich the practical experiences related to the design and construction of large underground openings, and the construction of caverns in the Jinping I hydropower station provides a good case study of large-scale excavation in highly stressed ground with complex geological structures, as well as a reference case for research on rock mechanics.

关键词： Large-scale underground caverns High in-situ stress Large deformationDeformation controlling technologies Jinping I hydropower station

Construction of isolated Ni sites on nitrogen-doped hollow carbon spheres with Ni-N_(3) configuration for enhanced reduction of nitroarenes

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Nano Research 2022年第7期15卷 6001-6009页

作者： Binbin feng Rou Guo Qiulan cai Yaping song Nan Li Yanghe Fu De-Li Chen Jiangwei Zhang Weidong Zhu Fumin Zhang Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhua 321004China Dalian National Laboratory for Clean Energy&State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Designing and synthesizing high-efficiency non-precious metal-based catalysts having uniform active sites increases the reactivity and selectivity of materials and provides a platform for an in-depth understanding of their catalytic reaction *** this study,we provided an approach for fabricating isolated nickel single-atom sites(Ni SAs)with high loading(4.9 wt.%)stabilized on nitrogen-doped hollow carbon spheres(NHCS)using a core–shell structured Zn/Ni bimetallic zeolitic imidazolate framework(ZIF)composite as the sacrificial *** as-fabricated Ni SAs/NHCS catalyst shows superior activity,selectivity,and recycling durability for the catalytic transfer hydrogenation of nitrobenzene to aniline,thus achieving 100%yield of aniline with a turn-over frequency(TOF)value as high as 29.9 h^(−1) under mild *** TOF value is considerably superior to the supported Ni nanoparticle *** experiments designed show that the hollow structure feature of NHCS facilitates accessible active sites and mass transfer,which thus contributes to the enhancement of the catalytic performance of Ni SAs/*** functional theory calculations show the high chemo-selectivity and activity of the Ni SAs catalyst,arising from the unique role of the single Ni-N3 site on simultaneously activating the H donor(N_(2)H_(4))and substrate,as well as the hydrogenation of the–NOH group as the rate-determining step.

关键词： single-atom catalyst chemo-selective reduction nitro compounds aromatic amines

Interface microstructure and formation mechanism of ultrasonic spot welding for Al-Ti dissimilar metals

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International Journal of Minerals,Metallurgy and Materials 2021年第9期28卷 1506-1514页

作者： Li Zhou Shan Liu Jie Min Zhi-Wei Qin Wen-Xiong He Xiao-Guo song Hong-Bo Xu Ji-cai feng State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology(Weihai)Weihai 264209China Research Center for Intelligent Chips Zhejiang LabHangzhou 311121China

The present study focuses on interface microstructure and joint ***6061 aluminum alloy(Al)and commercial pure titanium(Ti)joints were welded by ultrasonic spot welding(USW).The welding energy was 1100-3200 *** Al-Ti joint appearance and interface microstructure were observed mainly via optical microscopy and field emission scanning electron *** indicated that a good joint can be achieved only with proper welding energy of 2150 *** significant intermetallic compound(IMC)was found under all *** high energy barriers of Al-Ti and difficulties in diffusion were the main reasons for the absence of IMC according to kinetic *** heat input is crucial for the material plastic flow and bonding area,which plays an important role in the joint formation.

关键词： ultrasonic spot welding Al-Ti dissimilar material interface mechanism microstructure intermetallic compounds

Numerical Simulation for Accuracy of Velocity Analysis in Small-Scale High-Resolution Marine Multichannel Seismic Technology

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Journal of Ocean University of China 2017年第3期16卷 370-382页

作者： LUO Di cai feng WU Zhiqiang The Key Laboratory of Gas Hydrate Ministry of Land and ResourcesQingdao Institute of Marine Geology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology

When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positive results have been achieved in submarine geological research, particularly in the investigation of marine gas hydrates. However, the amount of traveltime difference information is reduced for the velocity analysis under conditions of a shorter spread length, thus leading to poorer focusing of the velocity spectrum energy group and a lower accuracy of the velocity analysis. It is thus currently debatable whether the velocity analysis accuracy of short-arrangement multichannel seismic detection technology is able to meet the requirements of practical application in natural gas hydrate exploration. Therefore, in this study the bottom boundary of gas hydrates(Bottom Simulating Reflector, BSR) is used to conduct numerical simulation to discuss the accuracy of the velocity analysis related to such technology. Results show that a higher dominant frequency and smaller sampling interval are not only able to improve the seismic resolution, but they also compensate for the defects of the short-arrangement, thereby improving the accuracy of the velocity analysis. In conclusion, the accuracy of the velocity analysis in this small-scale, high-resolution, multi-channel seismic detection technology meets the requirements of natural gas hydrate exploration.

关键词： small-scale high-resolution multichannel seismic velocity analysis accuracy gas hydrate

Difference beam aided target detection in monopulse radar

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Chinese Journal of Aeronautics 2015年第5期28卷 1485-1493页

作者： cai Fei Fan Hongqi song Zhiyong Fu Qiang ATR Key Laboratory National University of Defense Technology

The classical detection step in a monopulse radar system is based on the sum beam only, the performance of which is not optimal when target is not at the beam center. Target detection aided by the difference beam can improve the performance at this case. However, the existing difference beam aided target detectors have the problem of performance deterioration at the beam center, which has limited their application in real systems. To solve this problem, two detectors are proposed in this paper. Assuming the monopulse ratio is known, a generalized likelihood ratio test （GLRT） detector is derived, which can be used when targeting information on target direction is available. A practical dual-stage detector is proposed for the case that the monopulse ratio is unknown. Simulation results show that performances of the proposed detectors are superior to that of the classical detector.

关键词： Detection Difference beam Monopulse radar Sum beam Generalized likelihood ratiotest