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Palladium-catalyzed homo-coupling of boronic acids with supported reagents in supercritical carbon dioxide

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Chinese Chemical Letters 2007年第9期18卷 1043-1046页

作者： Lei Zhou Qiu Xiang Xu Huan Feng Jiang [a]college of Chemistry South China University of Technology Guangzhou 510640 China

Palladium-catalyzed homo-coupling of arylboronic acids could proceed smoothly with a commercially available resin functionlised by phosphino or amino group as the ligand in supercritical carbon dioxide thereby offerin... 详细信息

关键词： Homo-coupling Palladium scCO2 Bi-aryl

Solution of the Fermi-Ulam Model in the Case of Periodic Perturbation

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Chinese Physics Letters 2008年第5期25卷 1545-1548页

作者：李潮吴俊芳徐文成 college of Physical Science and technology South China University of Technology Guangzhou 510640 School for Information and Optoelectronic Science and Engineering South China Normal University Guangzhou 510631

We discuss the evolution of the state and the average energy of the Fermi Ulam model in the case of periodic perturbation. By a perturbation technique, the time-dependent Sehr6dinger equation is solved and it is found that the particle will continuously absorb or radiate energy Jf the frequency of the oscillating wall meets the resonance condition. Usually, these two states cannot exist together at a certain frequency. However, there is an exception if the frequency is at some special values. We find these values and reveal that the energy for transmission has the minimum equivalent unit, which is in the form of a harmonic oscillator.

关键词： ACCELERATOR BOUNDARY STATES

INTELLIGENT CAR STYLING TECHNIQUE AND SYSTEM BASED ON A NEW AERODYNAMIC-THEORETICAL MODEL

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Chinese Journal of Mechanical Engineering 2002年第2期15卷 110-115页

作者： Huang Xiangdong Xie Chaolin Xie Yuecongcollege of Traffic and Communications, south china university of technology,guangzhou 510640, china college of Traffic and Communications South China University of Technology Guangzhou 510640

Car styling technique based on a new theoretical model of automotiveaerodynamics is introduced, which is proved to be feasible and effective by wind tunnel *** of a multi-module software system from this technique, including modules of knowledgeprocessing, referential styling and ANN aesthetic evaluation etc, capable of assisting car stylingworks in an intelligent way, is also presented and discussed.

关键词： Automotive aerodynamics Artificial intelligence Computer aided styling

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science china(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Sciences university of Chinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Institute of Space Sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of Sciences Department of Physics university of Hong Kong School of Physics and Astronomy university of Leicester School of Physics and Astronomy Sun Yat-sen university Department of Physics Anhui Normal university Shanghai Institute of Technical Physics Chinese Academy of Sciences Physics Department Tsinghua university Nevada Center for Astrophysics university of Nevada Las Vegas Department of Physics and Astronomy university of Nevada Las Vegas south African Astronomical Observatory Department of Astronomy university of Cape Town Department of Physics university of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy guangzhou university Cosmic Dawn Center (DAWN) Niels Bohr Institute university of Copenhagen Department of Physics and Astronomy Rutgers the State university of New Jersey Institute for Cosmic Ray Research The university of Tokyo ESA/ESTEC Department of Astronomy School of Physics Huazhong university of Science and technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The university of Sydney Department of Astronomy Xiamen university Institute for Frontiers in Astronomy and Astrophysics Beijing Normal university Department of Astronomy university of Science and technology School of Astronomy and Space Sciences university of Science and technology of china Institute of Deep Space Sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan university Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

NOVEL COMPOSITE CVT SYSTEMS WITH DIVERGING AND DUAL-MODE CONVERGING POWER FLOW

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 257-262页

作者： Liu Shudao Huang Xiangdong Zhao Kegang Luo Yutao college of Traffic & Communications,south china university of technology,guangzhou 510640, china college of Traffc & Communications South China University of Technology Guangzhou 510640

A new type of composite CVT(continuously variable transmission) systemsfeatured by power flow divergence and dual-mode convergence, capable of improving CVT's efficiencyand power capacity or making AMTs(automated manual transmissions) become continuously variable, isstudied. With specific mechano-mechanical and electromechanical composite CVT systems as detailedexamples, its basic working principles are expatiated. General methods and key points in designingand realizing such systems are also analyzed and discussed.

关键词： Composite CVT Planetary gear set Dual-mode power convergence

Inversion of particle size distribution from light-scattering data using a modified regularization algorithm

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Particuology 2010年第4期8卷 365-371页

作者： Yanmin Wang Guobiao Liang Zhidong Pan college of Materials Science Engineering South China University of Technology Guangzhou 510640 China Key Laboratory of Specially Functional Materials and Advanced Manufacturing technology Ministry of Education South China University of Technology Guangzhou 510640 China

A modified regularization algorithm with a more proper operator was proposed for the inversion of particle size distribution （PSD） from light-scattering data in a laser particle sizer based on the Mie scattering principle. The Generalized Cross-Validation （GCV） method and the L-curve method were used for deter- mining the regularization parameter. The Successive Over-Relaxation （SOR） iterative method was used to increase the exactness and stability of the converged result. The simulated results based on the modified algorithm are in a good agreement with the experimental data measured for nine standard particulate samples, their mixtures as well as three natural particulate materials with irregular shapes, indicating that this modified regularization method is not only feasible but also effective for the simulation of PSD from corresponding light-scattering data.

关键词： Particle size measurement Mie scattering Laser particle size analyzerInverse algorithm

Spatiotemporal evolution of Ediacaran-Cambrian(ca. 551–523 Ma)sponges in south china and their simulated contributions to marine oxygenation

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Science china Earth Sciences 2025年

作者： Yan YE Lei ZHANG Can CHEN Shan CHANG Yuhao YI Qinglai FENG State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Wuhan) School of Earth Science China University of Geosciences(Wuhan) Department of Geology Lund University Institute of Sedimentary Geology Chengdu University of Technology Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of Technology Second Geological Brigade of Hubei Geological Bureau college of Urban and Environmental Sciences Hubei Normal University Exploration and Development Research Institute SINOPEC Jianghan Oilfield Company

The origin and evolution of sponges have attracted interest, not only because they are among the most basal metazoans, but also because they act as important ecological engineers in the ocean. Previous research suggested that sponge groups diversified quickly during the Cambrian Series 2, while Terreneuvian sponge fossils are conspicuously rare and poorly substantiated. Yet, an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C, ca.551–523 Ma) transitional carbonates/cherts worldwide, particularly in south china, which calls for updated discussions. Ocean oxygenation has been widely proposed to play a critical role in organismal evolution, but its relationship with sponges is unclear and falls into a “chicken-egg” dilemma. In this study, we summarize reported sponge spicule distributions from five E-C sections in south china to investigate the early evolutionary pattern of siliceous sponges. According to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area, and then potentially expand to the continental shelf and deep basin in the lower Cambrian. In these sections, the abundance, size, and diversity of monaxons increase upwards,followed by the appearance of diaxons, triaxons and then polyactines. Despite the uncertain affinity of the sponge fossils, it is possible that siliceous hexactinellids evolved later than siliceous demosponges, given that the earliest spicule assemblages are exclusively composed of monaxons, which commonly form bundles comparable to modern demosponges. New geochemical data from the Sifangjing section, Guizhou Province and the Yanziqiao section, Hunan Province, south china show that the appearance of sponges usually corresponds to anoxic environment. In addition, we applied the recently proposed Biological Pump, Oxygen and Phosphorus(BPOP) model to trace the evolution of oceanic oxygen concentrations with the radiation of sponges. The results indic

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Argon Plasma-Induced Graft Polymerization of PEGMA on Chitosan Membrane Surface for Cell Adhesion Improvement

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Plasma Science and technology 2013年第10期15卷 1041-1046页

作者： YIN Shiheng REN Li WANG Yingjun Analytical and Testing Center South China University of Technology Cuangzhou 510640China college of Materials Science and Engineering South China University of TechnologyGuangzhou 510640 China

For its biocompatibility and biodegradability, chitosan has had considerable atten- tion for biomedical applications in recent years. In this paper, polymerization of poly （ethylene glycol） methyl ether methacrylate （PEGMA） was grafted onto chitosan membrane surface through argon plasma-induced graft polymerization. The surface properties after modification were characterized by contact angle measurement, X-ray photoelectron spectroscopy （XPS） and atomic force microscopy （AFM）, respectively. The results indicated that PEGMA can be grafted successfully onto chitosan membrane surface. The surface hydrophilicity and free energy were improved and the surface roughness increased after modification. The adhesion of a human corneal epithelial cell （HCEC） on chitosan membrane surface was enhanced due to improvement of surface free energy and roughness.

关键词： chitosan membrane PEGMA plasma surface energy cell adhesion

New Bulb Turbine with Counter-rotating Tandem-runner

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 919-925页

作者： HAN Fengqin YANG Lijing YAN Shijie KUBOAT Takashi college of Electric Power South China University of Technology Guangzhou 510640 China Guangdong Technical college of Water Resources and Electric Engineering Guangzhou 510635 China

With the increasing demand for the clean sustainable power, the turbine design urgently turns to increase the capability significantly toward higher head for generating larger power. Currently, there are many studies in the field of the bulb turbine with single-stage runner, though reports about counter-rotating tandem-runner are rare. However, the further high-head application with the single-stage runner is very difficult to achieve due to the limit of the specific speed. In this paper, a new bulb turbine with the tandem-runner is designed in order to substantially increase the applicable limit toward higher head with larger power. A half of the net head is absorbed by the frontal runner which can generate output power, while the remaining half is absorbed by the rear runner. To generate the Euler energy required for the rear runner, the frontal runner has the counter-rotation against the rear runner so that the counter-rotating tandem-runner can meet the purpose of double head and power under the same size as the conventional bulb turbine. Supply and demand of Euler energy between the two runners are thoroughly optimized through the detailed flow analysis, in order to secure the stable operation. As a result, the interference of Euler energies between the outflow from the frontal runner and the inflow to the rear runner is confirmed to be very small on the counter-rotating interface between the two runners. The prediction method of on-cam performance between the two adjustable runners is also developed numerically, which provides optimal flow between the two runners. This research provides a theoretical basis for the optimal design and operation of the counter-rotating tandem-runner bulb turbines.

关键词： bulb turbine tandem-runner counter-rotating Euler energy power increase