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Chinese Chemical Letters 2022年第12期33卷 5092-5095页

作者： kui tian Gongyi Liu Xiu-Qin Dong Engineering Research Centre of Organosilicon Compounds&Materials Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Suzhou Institute of Wuhan University Suzhou 215123China

Highly enantioselective Rh-catalyzed partial hydrogenation of unprotected simple 2-alkyl-5-aryl-disubstituted pyrroles has been successfully developed,generating a series of chiral 1-pyrroline derivatives generally with excellent results(95%-99%yields,91%-96%ee).Moreover,2,5-aryl-1H-pyrroles were hydrogenated well in high yields and good *** efficient protocol features easily accessible substrates,wide substrate scope,well functional group compatibility,commercially available rhodium precursor and chiral *** provides a versatile route to access chiral 1-pyrroline derivatives that are of great importance in organic synthesis and pharmaceutical chemistry.

关键词： Chiral 1-pyrrolines Partial hydrogenation Unprotected simple pyrroles Regioselectivity Enantioselectivity

Min-max load balancing scheme for mixed multicast and unicast services in LTE networks

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The Journal of China Universities of Posts and Telecommunications 2012年第2期19卷 30-35页

作者： WANG Min FENG Chun-yan ZHANG tian-kui School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

To avoid the traffic congestion in long term evolution （LTE） networks, a min-max load balancing （LB） scheme is proposed to minimize the demanded radio resources of the maximum loaded cell. For the mixed multicast and unicast services, multicast services are transmitted by single frequency network （SFN） mode and unicast services are delivered with point-to-point （PTP） mode. The rain-max LB takes into account point-to-multipoint （PTM） mode for multicast services and selects the proper transmission mode between SFN and PTM for each multicast service to minimize the demanded radio resources of the maximum loaded cell. Based on the solution of this minimization problem, if the maximum loaded cell does not overload, the min-max LB will change PTM mode into SFN mode for mulficast services to achieve high quality of service （QoS）. Simulation results show that the proposed miu-max LB scheme requires less radio resources from the maximum loaded cell than SFN mode for all multicast services.

关键词： multicast and broadcast single frequency network load balancing point-to-multipoint quality of service

The research on floe ice force acting on the"Xue Long"icebreaker based on synthetic ice test and virtual mass numerical method

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Journal of Hydrodynamics 2021年第2期33卷 271-281页

作者： Wei Guo Qiao-sheng Zhao Yu-kui tian Wan-chao Zhang State Key Laboratory of Hydrodynamics China Ship Scientific Research CenterWuxi 214082China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

When the ice-going ships advance in the polar region,the navigation in the floe ice region is often encountered,the hull will suffer the high-frequency contact force produced by the floe ice,which will affect the navigation performance of the ***,it is necessary to predict the water and ice force acting on the hull *** this paper,the numerical simulation and experimental verification will be conducted for the polar scientific research ship-"Xue Long".Based on the computational fluid dynamics(CFD)and DEM theory,a virtual mass method is proposed to realize the predicting of the water and ice force and the simulation of the interaction phenomenon between the ice and hull,the numerical method is built to calculate the force acting on the *** the same time,the synthetic ice is used to carry out the experimental research on the advancing straight with different speeds and the oblique navigation with different drift *** optimal virtual mass coefficient is determined through the comparison and analysis of the numerical simulation and test results under typical *** to the optimal virtual mass coefficient,the numerical simulation is carried out with different speeds and drift angles,which is compared with the experiment more *** is found that the virtual mass method based on the combination of CFD and DEM can simulate the overturning and the sliding along the hull of the floe ice vividly,the relative error of the total resistance between model test and numerical method in advancing straight is almost within 10%,while the relative error of the total longitudinal force in oblique navigation is almost within 15%.

关键词： "Xue Long"ship synthetic ice model test computational fluid dynamics(CFD) DEM virtual mass method drift angle

Multi-cell uplink power allocation game for user minimum performance guarantee in OFDMA systems

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The Journal of China Universities of Posts and Telecommunications 2010年第5期17卷 6-11,49页

作者： ZHANG tian-kui XIAO Lin ZENG Zhi-min Laurie Cuthbert School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China China Academy of Telecommunications Research Ministry of Industry and Information Technology Beijing 100191 China Electronic Engineering and Computer Science Queen Mary University of London London E 1 4NS UK

The multi-cell uplink power allocation problem for orthogonal frequency division multiplexing access （OFDMA） cellular networks is investigated with the uplink transmission power allocation on each co-frequency subchannel being defined as a multi-cell non-cooperative power allocation game （MNPG）.The principle of the design of the utility function is given and a novel utility function is proposed for *** using this utility function,the minimum signal to interference plus noise ratio （SINR） requirement of a user can be *** can be shown that MNPG will converge to the Nash equilibrium and that this Nash equilibrium is *** considering the simulation results,the effect of the algorithm parameters on the system performance is discussed,and the convergence of the MNPG is *** performance of MNPG is compared with that of traditional power allocation schemes,the simulation results showing that the proposed algorithm increases the cell-edge user throughput greatly with only a small decrease in cell total throughput; this gives a good tradeoff between the throughput of cell-edge users and the system spectrum efficiency.

关键词： OFDMA power allocation non-cooperative game Nash equilibrium

Design, Synthesis and Application of Multifunctional Chiral Aminophosphine Catalyst for Asymmetric Intermolecular Cross Rauhut-Currier Reaction

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Chinese Journal of Chemistry 2022年第17期40卷 2061-2066页

作者： Wu-Wei Dong kui tian Xiu-Qin Dong Chun-Jiang Wang Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei430072 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai230021 China Suzhou Institute of Wuhan University SuzhouJiangsu215123 China

A series of structurally novel multifunctional chiral aminophosphine catalysts were developed through a concise synthetic strategy from easily available starting *** highly enantioselective intermolecular cross Rauhut-Currier reactions of vinyl ketones with 3-acyl acrylates and 2-ene-1,4-diones catalyzed by(S,S)-5a were well realized,generating a wide range of the structurally important chiral multicarbonyl products in good to excellent yields with high stereocontrol(up to 97%yield,99%ee).In addition,a series of 31P NMR experiments were carried out to further investigate the catalytic process.

关键词： Asymmetric catalysis Chiral aminophosphine Intermolecular cross Rauhut-Currier reaction Chiral multicarbonyl molecules Enantioselectivity

Asynchronous diversity receiving scheme and analysis on cooperative relay networks

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 10-15,35页

作者： ZHANG Ying-hui ZHANG tian-kui SAEED-Muhammad ZENG Zhi-min School of Information and Communication Engineering Beijing University of Posts and Telecommunications College of Electronic Information Engineering Inner Mongolia University School of Computer and Emerging Sciences National University of Computer and Emerging Sciences

The transmission antennas of cooperative systems are spatially distributed on multiple nodes, so the received signal can be asynchronous due to propagation delays. A receiving scheme for cooperative relay networks is proposed, multiple asynchronous signals are reconstructed at the receiver by forward and backward interference cancellation, which can obtain gains of cooperative transmission diversity with obvious delay and with no requiring timing synchronization or orthogonal channelization between relays. Analysis and simulation show that the bit error rate（BER） of the proposed scheme is similar to Alamouti code, and the scheme has the diversity order of orthogonal transmission scheme accompanied by minimal BER losses. It is demonstrated that the performance can be further improved by adding an error correcting code（ECC）.

关键词： relay networks asynchronous communications cooperative diversity interference cancellation

Facile one-pot hydrothermal method to prepare Sn(Ⅱ) and N co-doped TiO_(2) photocatalyst for water splitting under visible light irradiation

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Rare Metals 2022年第2期41卷 406-414页

作者： Xiao-Huan Jiang Ying-Nan Duan Yu tian Meng Chen Mao-Kun Li Huan-Huan Liu Wan-Liang Yang Meng-kui tian School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China

In this paper,a visible light-responsive Sn^(2+)and N co-doped TiO_(2)photocatalyst was prepared by facile one-pot hydrothermal *** as-prepared samples were characterized in detail by a series of characterization *** results showed that the Sn^(2+)and N elements were co-doped into TiO_(2),while the catalyst still maintains anatase crystal structure and gets irregular little nanocluster in diameter of 9–10 nm with higher specific surface *** absorption edge of Sn^(2+)and N co-doped TiO_(2)extends to the visible light *** with Sn^(2+)-doped TiO_(2)and N-TiO_(2),the absorption edges have obvious red-shift of about 50 and 70 nm,*** synergistic effect of O 2p-N 2p and O 2p-Sn 5s hybridization to form impurity levels is the main reason for the *** hydrogen production performance of the Sn^(2+)and N co-doping TiO_(2)(n(N)/n(Ti)=1)catalyst reached the maximum value of 0.37 mmol·h^(-1)·g^(-1)under visible light,which is higher than that of N-doped TiO_(2)and SnTiO_(2)-doped TiO_(2)*** result is due to the wider visible light region-responsive ability of Sn^(2+)and N codoped into TiO_(2).Furthermore,mild hydrothermal methods will not make the Sn^(2+)oxidized to Sn^(4+),which make the catalysts still maintain high photocatalytic *** work provides a simple and mild method for the preparation of dual-element co-doped TiO_(2)with high crystallinity,excellent performance and broad application prospects.

关键词： Photocatalyst Photocatalytic water splitting Visible light driven Sn^(2+)and N co-doped TiO_(2)

Two New Saponins from Lysimachia capillipes Hemsl.

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Journal of Integrative Plant Biology 2005年第10期47卷 1271-1275页

作者： Jing-kui tian Zhong-Mei ZOU Li-Zhen XU Shi-Lin YANG Department of Chinese Medicine Sciences and Engineering Zhejiang University Hangzhou 310027 China Institute of Medicinal Plants Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100094 China

To investigate the saponins from whole plants of Lysimachia capilUpes Hemsl., two new saponins, named capilliposide E （1） and capilliposide F （2）, were isolated. The structures of the new saponins were elucidated as 3β, 22α-dihydroxy-16α-acetat-28→ 13-lactone-oleanane-3-O- [β-D-glucopyranosyl- （1 →2）-α-L-arabinpyranoyl]-22-O-β-D-glucopyranoside （1） and 3β, 22α-dihydroxy- 16α-acetat-28→ 13-lactone-oleanane-3-O-{ [β-D-glucopyranosyl-（1→2）-β-D-glucopyranosyl-（1→4）]-α-L-arabinpyranoyl}-22-O-β- D-glucopyranoside （2）. The structures of these compounds were determined by 1D- and 2D-NMR, MS techniques, and chemical methods.

关键词： capilliposide E and F, Lysimachia capillipes triterpene saponin.

New Cytotoxic Saponins from Lysimachia davurica Ledeb.

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Journal of Integrative Plant Biology 2006年第2期48卷 232-235页

作者： Jing-kui tian Zhong-Mei Zou Li-Zhen Xu Shi-Lin Yang Department of Chinese Medicine Sciences and Engineering Zhejiang University Hangzhou 310028 China Institute of Medicinal Plants Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100094 China

To investigate the saponins from whole plants of Lysimachia davurica Ledeb., two new saponins named davuricoside I （compound 1） and E （compound 2） were isolated. Their chemical structures were elucidated as 3β, 16α, 28, 29-tetrihydroxy-olean-12-en-3-O-β-D-glucopyranosyl-（1→2）-β-D-glucuronopyranoside （compound 1） and 3β, 16α, 29-trihydroxy-13, 28-epoxy-oleanane-3-O-β-D-glucopyranosyl-（1→2）-β-D-glucuronopyranoside （compound 2） on the basis of their one- and two-dimensional nuclear magnetic resonance and mass spectrometry data, and chemical methods. Compound 1 showed significant cytotoxic activity against human A2780 cells.

关键词： davuricoside I and E Lysimachia davurica triterpene saponin.

Nash bargaining solution based multi-cell and multi-user interference alignment scheme for cellular networks

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The Journal of China Universities of Posts and Telecommunications 2014年第4期21卷 1-7,14页

作者： NIU Qin ZENG Zhi-min ZHANG tian-kui GAO Qiu-bin SUN Shao-hui School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunication Technology

In wireless cellular networks, the interference alignment （IA） is a promising technique for interference management. A new IA scheme for downlink cellular network with multi-cell and multi-user was proposed, in the proposed scheme, the interference in the networks is divided into inter-cell interference （ICI） among cells and inter-user interference （IUI） in each cell. The ICI is aligned onto a multi-dimensional subspace by multiplying the ICI alignment precoding matrix which is designed by the singular value decomposition （SVD） scheme at the base station （BS） side. The aligned ICI is eliminated by timing the interference suppression matrix which is designed by zero-forcing （ZF） scheme at the user equipment （UE） side. Meanwhile, the IUI is aligned by multiplying the IUI alignment precoding matrix which is designed based on Nash bargaining solution （NBS） in game theory. The NBS is solved by the particle swarm optimization （PSO） method. Simulations show that, compared with the traditional ZF IA scheme, the proposed scheme can obtain higher data rate and guarantee the data rate fairness of UEs with little additional complexity.

关键词： cellular network interference alignment Nash bargaining solution data rate fairness particle swarm optimization