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THE　BIRCH　REDUCTION　OF（1－OXO－CYCLOHEXENYLO）－2＇－［2＇，3＇，b］－6，7－MEHYLENEDIOXYBENZOZEPINE

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Chinese Chemical Letters 1994年第11期5卷 925-926页

作者： jiang Hong WANG yun zhen jiang Zhi Zhong ZHAO (Institute of Hateria Hedica Chinese Academy of Medical Sciences Beijing 100050)

As the result of Birch Reaction of(1'-oxo-cyclohexenylo)-2'-[2',3',b]-6 ,7 methylenedioxy bonzozepine,the cleavage of one of the phenolic ether bond of the methylenedioxy group was observed and the monohydroxy substit... 详细信息

关键词： OXO REDUCTION BIRCH MEHYLENEDIOXYBENZOZEPINE OF CYCLOHEXENYLO

Behavior and Regularity Analysis of Online Topic Spreading

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Journal of Electronic Science and Technology 2011年第2期9卷 155-160页

作者： Yan-Chao Zhang yun Liu zhen-jiang Zhang Beijing Jiaotong University Beijing 100044China

The spread of online topics,which is a complex socio-psychological and information dissemination process,can significantly influence the online public opinion. The behavior of online topics spreading is explored and its regularity is attempted to analyze. A general model for the spread of online topics is introduced,and the differential equation that describes the velocity of an online topic＇s spreading is derived. The velocity of an online topic＇s spread indicates the level of the topic＇s development and reflects its popularity over time. The proposed model has been theoretically analyzed and empirically studied,respectively. By analyzing the data set from a famous Internet forum,it is shown that the development of spread velocity of online topics has some certain features and our model matches the laws of reality. This method,which is suitable for forecasting the development trend of online topics’ spread velocity in short term,is also critical to the success of online topics’ regularity analysis.

关键词： Differential equations forecast information diffusion online topic

The tangential k-Cauchy-Fueter type operator and Penrose type integral formula on the generalized complex Heisenberg group

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 181-190页

作者： REN Guang-zhen SHI yun KANG Qian-qian Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023China Department of Mathematics Zhejiang University of Science and TechnologyHangzhou 310023China

The tangential k-Cauchy-Fueter operator and k-CF functions are counterparts of the tangential Cauchy–Riemann operator and CR functions on the Heisenberg group in the theory of several complex variables,*** this paper,we introduce a Lie group that the Heisenberg group can be imbedded into and call it generalized complex *** investigate quaternionic analysis on the generalized complex *** also give the Penrose integral formula for k-CF functions and construct the tangential k-Cauchy-Fueter complex.

关键词： the generalized complex Heisenberg group the tangential k-Cauchy-Fueter type operator Penrose-type integral formula

Sum-Rate Maximization in Active RIS-Assisted Multi-Antenna WPCN

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China Communications 2024年第6期21卷 23-39页

作者： jiang Jie Lyu Bin Chen Pengcheng Yang zhen School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology Nanjing UniversityNanjing 210003China

In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both wireless energy transfer(WET)from the power station(PS)to energyconstrained users and wireless information transmission(WIT)from users to the receiving station(RS).For further performance enhancement,we propose to employ both transmit beamforming at the PS and receive beamforming at the *** formulate a sumrate maximization problem by jointly optimizing the RIS phase shifts and amplitude reflection coefficients for both the WET and the WIT,transmit and receive beamforming vectors,and network resource *** solve this non-convex problem,we propose an efficient alternating optimization algorithm with the linear minimum mean squared error criterion,semidefinite relaxation(SDR)and successive convex approximation ***,the tightness of applying the SDR is *** results demonstrate that our proposed scheme with 10 reflecting elements(REs)and 4 antennas can achieve 17.78%and 415.48%performance gains compared to the single-antenna scheme with 10 REs and passive RIS scheme with 100 REs,respectively.

关键词： active reconfigurable intelligent surface beamforming sum-rate maximization wireless powered communication network

SDCC: software-defined collective communication for distributed training

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Science China(Information Sciences) 2024年第9期67卷 105-125页

作者： Xin JIN zhen ZHANG yunshan JIA yun MA Xuanzhe LIU School of Computer Science Peking University Department of Computer Science and Technology Johns Hopkins University

Communication is crucial to the performance of distributed training. Today's solutions tightly couple the control and data planes and lack flexibility, generality, and performance. In this study, we present SDCC, a software-defined collective communication framework for distributed training. SDCC is based on the principle of modern systems design to effectively decouple the control plane from the data *** abstracts the operations for collective communication in distributed training with dataflow operations and unifies computing and communication with a single dataflow graph. The abstraction, together with the unification, is powerful: it enables users to easily express new and existing collective communication algorithms and optimizations, simplifies the integration with different computing engines(e.g., Py Torch and Tensor Flow) and network transports(e.g., Linux TCP and kernel bypass), and allows the system to improve performance by exploiting parallelism exposed by the dataflow graph. We further demonstrate the benefits of SDCC in four use cases.

关键词： machine learning systems distributed training deep learning collective communication software-defined networking

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BASIC HYDROLYSIS OF ETHYL OXAL-ACETATE AND SOME CHEMICAL CHARACTERS OF 3-ETHOXY CAEBONYL PYRUVIC ACID

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Chinese Chemical Letters 1992年第3期3卷 171-172页

作者： yun zhen jiang, Dong WEI and Zhi Zhong ZHAO Institute of Materia Medica Chinese Academy of Medical Sciences Beijing 100050

The products of basic hydrolysis of ethyl oxal-acetate and the preparation of 3-ethoxy carbonyl pyruvic acid 1 are *** reaction of 1 with unhindered alcohols could be carried out smoothly, but it was unsuccessful with... 详细信息

关键词： BASIC HYDROLYSIS OF ETHYL OXAL-ACETATE AND SOME CHEMICAL CHARACTERS OF 3-ETHOXY CAEBONYL PYRUVIC ACID HO OC ACID

Ca_(2)MnO_(4)-layered perovskite modified by NaNO_(3)for chemical-looping oxidative dehydrogenation of ethane to ethylene

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Chinese Journal of Chemical Engineering 2024年第4期68卷 53-64页

作者： Weixiao Ding Kun Zhao Shican jiang zhen Huang Fang He College of Chemistry and Bioengineering Guilin University of TechnologyGuilin 541006China Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Chemical-looping oxidative dehydrogenation(CL-ODH)is a process designed for the conversion of alkanes into olefins through cyclic redox reactions,eliminating the need for gaseous O_(2).In this work,we investigated the use of Ca_(2)MnO_(4)-layered perovskites modified with NaNO_(3) dopants,serving as redox catalysts(also known as oxygen carriers),for the CL-ODH of ethane within a temperature range of 700-780℃.Our findings revealed that the incorporation of NaNO_(3) as a modifier significantly-nhanced the selectivity for-thylene generation from Ca_(2)MnO_(4).At 750℃and a gas hourly space velocity of 1300 h^(-1),we achieved an-thane conversion up to 68.17%,accompanied by a corresponding-thylene yield of 57.39%.X-ray photoelectron spectroscopy analysis unveiled that the doping NaNO_(3) onto Ca_(2)MnO_(4) not only played a role in reducing the oxidation state of Mn ions but also increased the lattice oxygen content of the redox ***,formation of NaNO_(3) shell on the surface of Ca_(2)MnO_(4) led to a reduction in the concentration of manganese sites and modulated the oxygen-releasing behavior in a step-wise *** modulation contributed significantly to the enhanced selectivity for ethylene of the NaNO_(3)-doped Ca_(2)MnO_(4) *** findings provide compelling evidence for the potential of Ca_(2)MnO_(4)-layered perovskites as promising redox catalysts in the context of CL-ODH reactions.

关键词： Chemical-looping oxidative dehydrogenation Ethane Ethylene NaNO_(3)-doped Ca_(2)MnO_(4)redox catalyst Layered perovskites

Assembly of peptide nanostructures with controllable sizes

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Nano Research 2024年第1期17卷 151-161页

作者： Dan Cheng Fan Jia yun-Bao jiang Vincent P.Conticello Tao jiang The MOE Key Laboratory of Spectrochemical Analysis and Instrumentation Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China Department of Chemistry Emory UniversityAtlanta 30033USA

Controlled peptide assembly offers significant promise to develop synthetic supramolecular nanostructures to display material and biological properties that mimic protein assemblies in *** the progress in forming peptide nanostructures of various morphology,there exists a distinct gap between natural and synthetic assembly systems in terms of size *** nanostructures with a narrow size distribution that can be tuned over a wide range of length-scales is essential for applications that require precise spacing between *** approach provides the opportunity to correlate materials and biological properties of interest with assembly *** this review,we discuss representative endeavors over the past two decades for design of size-controllable peptide nanostructures using tunable building *** mechanisms for size control,e.g.,molecular frustration,template-directed peptide assembly,and multi-component peptide co-assembly,will also be *** also demonstrate the applicable scopes of these strategies and suggest potential future avenues for scientific advances in this field.

关键词： peptide assembly controllable size template multi-component

Application of neoadjuvant chemoradiotherapy and neoadjuvant chemotherapy in curative surgery for esophageal cancer:A metaanalysis

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 214-233页

作者： Mao-Xiu Yuan Qi-Gui Cai zhen-Yang Zhang Jian-Zhong Zhou Cai-yun Lan jiang-Bo Lin The Graduate School Fujian Medical UniversityFuzhou 350000Fujian ProvinceChina Department of Thoracic Surgery Affiliated Hospital of Jinggangshan UniversityJi’an 343000Jiangxi ProvinceChina Department of Thoracic Surgery Fujian Medical University Union HospitalFuzhou 350000Fujian ProvinceChina

BACKGROUND The effectiveness of neoadjuvant therapy in esophageal cancer(EC)treatment is still a subject of *** To compare the clinical efficacy and toxic side effects between neoadjuvant chemoradiotherapy(nCRT)and neoadjuvant chemotherapy(nCT)for locally advanced EC(LAEC).METHODS A comprehensive search was conducted using multiple databases,including PubMed,EMBASE,MEDLINE,Science Direct,The Cochrane Library,China National Knowledge Infrastructure,Wanfang Database,Chinese Science and Technology Journal Database,and Chinese Biomedical Literature Database *** up to December 2022 comparing nCRT and nCT in patients with EC were *** The analysis revealed significant differences between nCRT and nCT in terms of disease-free *** results indicated that nCRT provided better outcomes in terms of the 3-year overall survival rate(OSR)[odds ratio(OR)=0.95],complete response rate(OR=3.15),and R0 clearance rate(CR)(OR=2.25).However,nCT demonstrated a better 5-year OSR(OR=1.02)than ***,when compared to nCRT,nCT showed reduced risks of cardiac complications(OR=1.15)and pulmonary complications(OR=1.30).CONCLUSION Overall,both nCRT and nCT were effective in terms of survival outcomes for ***,nCT exhibited better performance in terms of postoperative complications.

关键词： Esophageal cancer Neoadjuvant chemoradiotherapy Radical resection for esophageal cancer Neoadjuvant chemotherapy Meta-analysis