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A review of enantioselective dual transition metal/photoredox catalysis

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Science China Chemistry 2020年第5期63卷 637-647页

作者： hong-hao zhang Hui Chen Chengjian Zhu Shouyun Yu Jiangsu Key Laboratory of Advanced Organic Materials School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Transition metal catalysis is one of the most important tools to construct carbon-carbon and carbon-heteroatom bonds in modern organic synthesis. Visible-light photoredox catalysis has recently drawn considerable attention of the scientific community owing to its unique activation modes and significance for the green synthesis. The merger of photoredox catalysis with transition metal catalysts, termed metallaphotoredox catalysis, has become a popular strategy for expanding the synthetic utility of visiblelight photocatalysis. This strategy has led to the discovery of novel asymmetric transformations, which are unfeasible or not easily accessible by a single catalytic system. This contemporary area of organic chemistry holds promise for the development of economical and environmentally friendly methods for the asymmetric synthesis of chiral compounds. In this review, the advances in the enantioselective metallaphotoredox catalysis(EMPC) are summarized.

关键词： transition metal catalysis photoredox catalysis dual catalysis asymmetric catalysis

Fast and high-fidelity generation of photonic Greenberger-Horne-Zeilinger states in circuit QED

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Communications in Theoretical Physics 2020年第1期72卷 52-59页

作者： Jingwei Chen Guan-hao Feng hong-hao zhang L F Wei School of Physics Sun Yat-sen UniversityGuangzhou 510275China Photonics Laboratory and Institute of Functional Materials College of ScienceDonghua UniversityShanghai 201620China Information Quantum Technology Laboratory School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China

A fast scheme to generate Greenberger-Horne-Zeilinger states between different cavities in circuit QED systems is *** implement this scheme,we design a feasible experimental device with three qubits and three *** this device,all the couplings between qubit and qubit,cavity and qubit are tunable and are independent with frequencies,and thus the shortcut to adiabaticity technique can be directly applied in our *** is demonstrated that the GHZ state can be generated rapidly with high fidelity in our scheme.

关键词： GHZ states shortcut to adiabaticity quantum state engineering circuit QED

The history, hotspots, and trends of electrocardiogram

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Journal of Geriatric Cardiology 2015年第4期12卷 448-456页

作者： Xiang-Lin YANG Guo-Zhen LIU Yun-Hai TONG hong YAN Zhi XU Qi CHEN Xiang LIU hong-hao zhang hong-Bo WANG Shao-Hua TAN Key Laboratory of Machine Perception (Ministry of Education) School of Electronics Engineering and Computer Science Peking University Beijing China State Key Laboratory of Space Medicine Fundamentals and Application China Astronaut Research and Training Center Beijing China Institute for Medical Humanities Peking University Health Science Center Beijing China Department of Geriatric Cardiology Chinese PLA General Hospital Beijing China PKU Healthcare IT Co. Ltd. Beijing China

The electrocardiogram （ECG） has broad applications in clinical diagnosis and prognosis of cardiovascular disease. Many researchers have contributed to its progressive development. To commemorate those pioneers, and to better study and promote the use of ECG, we reviewed and present here a systematic introduction about the history, hotspots, and trends of ECG. In the historical part, information including the invention, improvement, and extensive applications of ECG, such as in long QT syndrome （LQTS）, angina, and myocardial infarction （MI）, are chronologi- cally presented. New technologies and applications from the 1990s are also introduced. In the second part, we use the bibliometric analysis me- thod to analyze the hotspots in the field of ECG-related research. By using total citations and year-specific total citations as our main criteria, four key hotspots in ECG-related research were identified from 11 articles, including atrial fibrillation, LQTS, angina and MI, and heart rate variability. Recent studies in those four areas are also reported. In the final part, we discuss the future trends concerning ECG-related research. The authors believe that improvement of the ECG instrumentation, big data mining for ECG, and the accuracy of diagnosis and application will be areas of continuous concern.

关键词： Electrocardiogram History Hotspots Review Trends

Effect of solidification mode on microstructure evolution and properties of magnesium alloy with long-period stacking ordered phase

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Journal of Iron and Steel Research International 2024年第5期31卷 1127-1138页

作者： hao Li hong-mei Chen Xu zhang Qian-hao Zang Jing zhang Di Feng Yan-xin Qiao Yu-hang Guo School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212100JiangsuChina School of Metallurgy and Materials Engineering Jiangsu University of Science and TechnologySuzhou215600JiangsuChina

The solidification methods of electromagnetic stirring(EMS)and non-electromagnetic stirring were employed to prepare Mg–6Gd–3Y–xZn–0.6Zr(x=1,1.5,2,3)*** evolution of alloy microstructures and the changes in properties were analyzed for different Zn *** has been observed that in alloys without electromagnetic stirring,as the Zn content increases,the alloy structure gradually *** primary second phase transitions from Mg5RE phase to long-period stacking ordered(LPSO)phase,resulting in improved hardness and *** alloys subjected to electromagnetic stirring,there is a relatively higher content of the second phase,primarily consisting of LPSO *** applying electromagnetic stirring,the quantity and the type of LPSO phase in the alloy *** alloy structure becomes more uniform with electromagnetic stirring,resulting in increased hardness and reduced hardness gradients within the *** mechanical properties of alloys with electromagnetic stirring are superior to those without electromagnetic stirring.

关键词： Rare earth magnesium alloy LPSO phase Electromagnetic stirring Casting Property

Performance improvement of β-Ga2O3 SBD-based rectifier with embedded microchannels in ceramic substrate

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Science China(Information Sciences) 2024年第5期67卷 341-342页

作者： Wen hong Chao zhang Fang zhang Xuefeng ZHENG Xiaohua MA Yue hao State Key Laboratory of Wide-Bandgap Semiconductor Devices and Integrated Technology School of MicroelectronicsXidian University

With the development of integrated circuits, there is a growing demand for higher power devices [1]. Gallium oxide（Ga2O3） holds promise for high power devices due to its wide bandgap and high breakdown electric field strength [2].However, its low thermal conductivity induces severe selfheating effects, limiting its performance and ***, effective thermal management techniques are urgently needed for Ga2O3devices.

关键词： Gallium compounds

Heterogeneous engineering of MnSe@NC@ReS_(2) core-shell nanowires for advanced sodium-/potassium-ion batteries

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Rare Metals 2024年第8期43卷 3713-3723页

作者： Sheng-Jun Lu Jin-Yi Lin Cai-hong Wang Yu-Fei zhang Yi zhang hao-Sen Fan College of Materials Science and Metallurgy Engineering Guizhou University Guiyang 550025China School of Energy Science and Engineering Nanjing Tech UniversityNanjing 211816China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) have been attracting great attentions and widely been exploited due to the abundant sodium/potassium ***,the preparation of high-powered anode materials for SIBs/PIBs plays a decisive role for the commercial applications of SIBs/PIBs in the *** selenides are a class of potential anode materials for SIBs/PIBs because of their small band gap and high electrical *** this work,MnSe and ReS_(2) core-shell nanowires connecting by polydopamine derived carbon nanotube(MnSe@NC@ReS_(2)) have been successfully synthesized from growing ReS_(2) nanosheets array on the surface of MnSe@NC nano wires,which present excellent Na^(+)/K^(+) storage *** applied as SIBs anode,the specific capacity of 300 mAh·g^(-1) was maintwined after 400 cycles at the current density of 1.0 A·g^(-1).Besides,it could also keep 120 mAh·g^(-1) specific capacity after 900 cycles at 1.0 A·g^(-1) for the anode of *** heterogeneous engineering and one-dimensional-two-dimensional(1D-2D) hybrid strategies could provide an ideal strategy for the synthesis of new hetero-structured anode materials with outstanding battery performance for SIBs and PIBs.

关键词： Heterogeneous engineering Core-shell nanowires MnSe@NC@ReS_(2)nanowires Na^(+)batteries K^(+)batteries

Phosphine-catalyzed acyl-transfer of heteroaryl ketones for the construction of N-fused heterocycles

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Chinese Chemical Letters 2024年第3期35卷 252-256页

作者： Yu zhang De-Rui Han Dan Ye hong Lu hao Wei Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710069China

An inexpensive phosphine catalyst was used effectively for a transition-metal-free acyl-transfer of N-containing heteroaryl ketones for the rapid synthesis of N-fused *** key pre-aromatic spirocyclic intermediate initialized by the single electron transfer(SET)process of Togni's reagentⅡpromoted by the tertiary phosphine resulted in an intriguing and alternative tactic for the cleavage of C–C *** using inexpensive tertiary phosphine as the catalyst,this skeleton-reorganizing approach of N-containing heteroaryl ketones allows a streamlined assembly of complex N-fused heterocycles with broad functional group tolerance.

关键词： Phosphine catalysis Acyl-transfer N-Fused heterocycles C–C bond activation Aromatization

Scalar quintuplet minimal dark matter with Yukawa interactions:perturbative up to the Planck scale

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Chinese Physics C 2019年第2期43卷 20-30页

作者： Zhu Luo Cheng-feng Cai Zhao-feng Kang Zhao-huan Yu hong-hao zhang School of Physics Sun Yat-Sen University School of Physics Huazhong University of Science and Technology ARC Centre of Excellence for Particle Physics at the Terascale School of PhysicsThe University of Melbourne

We confront the perturbativity problem in the real scalar quintuplet minimal dark matter model. In the original model, the quintuplet quartic self-coupling inevitably hits a Landau pole at a scale ～10^(14) GeV, far below the Planck scale. In order to push up this Landau pole scale, we extend the model with a fermionic quintuplet and three fermionic singlets which couple to the scalar quintuplet via Yukawa interactions. Involving such Yukawa interactions at a scale ～10^(10) GeV can not only keep all couplings perturbative up to the Planck scale, but can also explain the smallness of neutrino masses via the type-I seesaw mechanism. Furthermore, we identify the parameter regions favored by the condition that perturbativity and vacuum stability are both maintained up to the Planck scale.

关键词： dark matter phenomenology renormalization group equations Landau pole vacuum stability

Enhancing SAEAs with unevaluated solutions:a case study of relation model for expensive optimization

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Science China(Information Sciences) 2024年第2期67卷 41-58页

作者： hao hao Xiaoqun zhang Aimin ZHOU Institute of Natural Sciences Shanghai Jiao Tong University Shanghai Frontiers Science Center of Molecule Intelligent Syntheses School of Computer Science and Technology East China Normal University

Surrogate-assisted evolutionary algorithms(SAEAs) hold significant importance in resolving expensive optimization problems. Extensive efforts have been devoted to improving the efficiency of SAEAs through the development of proficient model-assisted solution selection methods, which, however, first requires generating high-quality solutions. The fundamental paradigm of evaluating a limited number of solutions in each generation within SAEAs reduces the variance of adjacent populations, thereby affecting the quality of offspring solutions. This is a frequently encountered issue yet receives little attention. To address the issue, this paper presents a framework using unevaluated solutions to enhance the efficiency of *** surrogate model is employed to identify high-quality solutions for the direct generation of new solutions without evaluation. To ensure dependable selection, we have introduced two tailored relation models to select the optimal solution and the unevaluated population. A comprehensive experimental analysis is performed on two test suites, which showcases the superiority of the relation model over regression and classification models in the solution selection phase. Furthermore, the surrogate-selected unevaluated solutions with high potential have been shown to enhance the efficiency of the algorithm significantly.

关键词： expensive optimization unevaluated solutions relation model surrogate-assisted evolutionary algorithm