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Science China Chemistry 2021年第7期64卷 1177-1183页

作者： Zi-en Zhang Yuan-Yuan An bo Zheng Jin-Ping Chang Ying-Feng Han College of Chemistry and Materials Science Northwest UniversityXi'an 710127China School of Pharmaceutical Sciences Nanjing Tech UniversityNanjing 211816China

The hierarchical self-assembly(HSA) strategy widely utilized in biological systems has been applied in artificial systems to orchestrate small building blocks into complex functional architectures. The non-interfering interactions glue various building blocks together and produce new species with attractive properties. Herein, we functionalized NHC-based assemblies with orthogonal host–guest interaction to fabricate metal-carbene based supramolecular polymer gel. A series of unique crown etherappended cylinder-like trinuclear AuIhexacarbene assemblies [Au_(3)(L)_(2)](PF_(6))_(3)(L=D1–D4, A1–A4) were synthesized from the corresponding trisimidazolium salts H_(3)-L(PF_(6))_(3)(L=D1–D4, A1–A4) in which the N-wingtip of the imidazole moieties were substituted with three identical crown ether groups of different sizes(B15C5, B18C6, B21C7, DB24C8). The gold carbene assembly is able to complex six ammonium salts without disrupting the underlying metal-carbene cylinders. In addition, the supramolecular polymer metallogel featuring a multiple-responsiveness can be formed by using [Au_(3)(A_(4))_(2)](PF_(6))_(3) appended with DB24C8 as the core and bisammonium salt as the cross-linker. The case of introducing orthogonal interaction to NHC moiety by N-wingtip substitution demonstrates the feasibility and the power of such strategy to expand the NHC-based supramolecular system and endow them with novel properties.

关键词： N-heterocyclic carbene metallogel crown ether orthogonal interaction

Resource allocation with minimum transmit power in multicast OFDM systems

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Journal of Systems engineering and Electronics 2010年第3期21卷 355-360页

作者： bo wu Jun Shen Haige Xiang School of Electronics engineering and Computer Science Peking University Beijing 100871 R R. China

To minimize the total transmit power for multicast service in an orthogonal frequency division multiplexing（OFDM） downlink system,resource allocation algorithms that adaptively allocate subcarriers and bits are *** proposed algorithms select users with good channel conditions for each subcarrier to reduce the transmit power,while guaranteeing each user＇s instantaneous minimum rate *** resource allocation problem is first formulated as an integer programming（IP） problem,and then,a full search algorithm that achieves an optimal solution is *** reduce the computation load,a suboptimal algorithm is *** suboptimal algorithm decouples the joint resource allocation problem by separating subcarrier and bit ***-like algorithms are employed in both *** results illustrate that the proposed algorithms can significantly reduce the transmit power compared with the conventional multicast approach and the performance of the suboptimal algorithm is close to the optimum.

关键词： resource allocation multicast orthogonal frequency division multiplexing (OFDM) integer programming (IP) greedy algorithm.

Dynamic models of technology management capability development based on knowledge diffusion

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Journal of Systems engineering and Electronics 2011年第2期22卷 228-237页

作者： Weiwei wu bo Yu Jian Wang School of Management Harbin Institute of Technology Harbin 150001 P. R. China . China Aerospace Science & Industry Corporation Beijing 100830 P. R. China

Technology management is recognized as a key for organizations to achieve competitiveness. How to promote an organization’s technology management capability is of great significance in creating efficiencies and achieving a competitive edge. The knowledge essence of technology management capability is introduced and then the correlation between knowledge diffusion and the development of technology management capability is discussed. Further, the basic and extended dynamic models of the development of technology management capability are constructed, and is applied into an enterprise. The results show that the dynamic models can well explain how the knowledge improves the development of technology management capability, and they can be used as an useful tool by an enterprise to promote technology management capability. Finally, the managerial implications of the models are discussed.

关键词： technology management knowledge diffusion dynamic model.

Study of the toluene absorption capacity and mechanism of ionic liquids using COSMO-RS prediction and experimental verification

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Green energy & environment 2021年第3期6卷 339-349页

作者： Chenglong Zhang Jin wu Ruixue Wang en Ma Liang wu Jianfeng Bai Jingwei Wang Research Center of Resource Recycling Science and engineering Shanghai Polytechnic UniversityJinhai Road No.2360Pudong New DistrictShanghai201209China Shanghai Collaborative Innovation Centre for WEEE Recycling Shanghai Polytechnic UniversityJinhai Road No.2360Pudong New DistrictShanghai201209China Department of Physics Shanghai UniversityShangda Road No.99Baoshan DistrictShanghai200444China

As green solvents,ionic liquids(ILs)are quite suitable for the absorption of volatile organic compounds(VOCs)such as benzene and its ***,solvent selection is the key to the VOC absorption *** the present study,a rapid solvent screening tool,Conductor-like Screening Model for Real Solvents(COSMO-RS),was used to predict the solubility of toluene in 816 *** effects of four structure characters,namely,the type and alkyl chain length of the cations and anions on the solubility of toluene were *** following conclusions were drawn from the results:(1)ILs with pyrrolidinium-based cations showed better solubility than pyridinium-and imidazoliumbased ones.(2)The solubility of toluene in PF6-based ILs increased with the increasing alkyl chain length,while its solubility in Ac-based ILs exhibited the opposite trend.(3)Toluene showed greater solubility in Cl-based ILs than those based on other anions.(4)The solubility of toluene increased with the anion alkyl chain ***-based ILs were chosen as the most promising potential solvents,and further studied to determine the relationship between various interaction energy parameters and toluene *** results showed that the misfit energy played a dominant role during the absorption ***,several ILs were selected for experimental verification of the predicted solubility behavior using liquid and gaseous *** results demonstrated that COSMO-RS could be used to semi-quantitatively and qualitatively predict the solubility of toluene,and this model had promising prospects in screening ILs for VOCs *** summary,this study provided a fundamental basis and practical data for the control and treatment of VOCs.

关键词： Solubility prediction COSMO-RS Toluene Ionic liquids

Microstructure evolution of an ultra-high strength metal alloy with tempering temperature

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Rare Metals 2012年第5期31卷 442-445页

作者： wu Sujun HU Bin HAN bo School of Materials Science and engineering Beijing University of Aeronautcs and Astronautics Beijing 100191 China

Optical microscopy (OM) and transmission electron microscopy (TEM) were used to investigate the effect of tempering temperature on the experimental extra-high carbon steels. It is found that tempering reaction can reduce austenite content and influence the stability of the austenite. As-normalized microstructure is a mixture of twinned martensite and retained austenite. Tempered at 250 °C for 2 h, lath martensite can occasionally be found nearby the diffusionally decomposed austenite area. It also is found that tempering at 650 °C for 2 h, nanoparticles of carbides precipitate in the martensite and decomposed austenite. © The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg 2012.

关键词： Austenite Carbides Carbon steel High strength alloys Martensite Microstructure Optical microscopy Transmission electron microscopy

Comparative Studies of Substrate and Inhibitor Specificity of Glutathione S-Transferases in Six Tissues of Oxya chinensis(Thunberg)(Orthoptera:Acrididae)

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Agricultural Sciences in China 2008年第4期7卷 462-468页

作者： wu Hai-hua ZHU Kun-yan GUO Ya-ping ZHANG Xiao-min MA en-bo Institute of Applied Biology Shanxi University Taiyuan 030006 P.R.China Department of entomology Kansas State University Manhattan 66506 USA

Specific activity, substrate specificity, and kinetic parameters （Km and Vmax） of glutathione S-transferases （GSTs） towards three substrates, 1-chloro-2,4-dinitrobenzene （CDNB）, 1,2-dichloro-4-nitrobenzene （DCNB）, and p-nitrobenzene chloride （pNBC） were investigated in six tissues （foregut, midgut, hindgut, fat body, hemolymph, and muscle） of Oxya chinensis. In addition, the inhibition in vitro （ethacrynic acid, and Cibacron Blue 3GA） of Oxya chinensis in the six tissues was also investigated. Glutathione S-transferase activity was detected in all the six tissues examined. The rank order of GST activities towards CDNB was fat body 〉 midgut 〉 hindgut 〉 muscle 〉 foregut 〉 hemolymph both in females and males. Glutathione S-transferase activities in the fat body in females and males were 1.3- to 10.4-fold and 1.1- to 10.0- fold higher than those in the other tissues. The rank order of GST activities towards the other substrates changed slightly. From these results, it was inferred that GSTs in the fat body and midgut played important roles in detoxifying xenobiotics including insecticides and plant allelochemicals in O. chinensis. In the three substrates examined, CDNB seemed to be the best substrate, followed by pNBC and DCNB. The kinetic parameters of GSTs were different among the six tissues. This suggested that GSTs in different tissues have various affinities and catalytic efficiency to substrates. In vitro inhibition study showed that the median inhibition concentration （IC50） values of the two inhibitors to GSTs from the six tissues were different. The results suggested that the two inhibitors have different inhibition potency to GSTs from the different tissues. The observed changes in kinetic parameters and inhibition in vitro among the six tissues of the insect might suggest that the number and structure of isoenzymes and their rate of expression varied for the different tissues.

关键词： Oxya chinensis glutathione S-transferase (GST) tissue distribution kinetic parameters inhibition in vitro

A Buffer Scheduling Method Based on Message Priority in Delay Tolerant Networks

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Journal of Computer Science & Technology 2016年第6期31卷 1228-1245页

作者： en Wang Yong-Jian Yang Jie wu Wen-Bin Liu Department of Computer Science and Technology Jilin University Changchun 130012 China Department of Computer and Information Sciences Temple University Philadelphia 19122 U.S.A. Department of Software Jilin University Changchun 130012 China

Routing protocols in delay tolerant networks usually utilize multiple message copies to guarantee the message delivery, in order to overcome unpredictable node mobility and easily-interrupted connections. A store-carry-and-forward paradigm was also proposed to further improve the message delivery. However, excessive message copies lead to the shortage of buffer and bandwidth. The spray and wait routing protocol has been proposed to reduce the network overload caused by the buffer and transmission of unrestricted message copies. However, when a node＇s buffer is quite constrained, there still exist congestion problems. In this paper, we propose a message scheduling and drop strategy on spray and wait routing protocol （SDSRP）. To improve the delivery ratio, first of all, SDSRP calculates the priority of each message by evaluating the impact of both replicating and dropping a message copy on delivery ratio. Subsequently, scheduling and drop decisions are made according to the priority. In order to further increase delivery ratio, we propose an improved message scheduling and drop strategy on spray and wait routing protocol （ISDSRP） through enhancing the accuracy of estimating parameters. Finally, we conduct extensive simulations based on synthetic and real traces in ONE. The results show that compared with other buffer management strategies, ISDSRP and SDSRP achieve higher delivery ratio, similar average hopcounts, and lower overhead ratio.

关键词： delay tolerant network spray and wait buffer scheduling priority

Two-Parameter Block Triangular Splitting Preconditioner for Block Two-by-Two Linear Systems

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Communications on Applied Mathematics and Computation 2023年第4期5卷 1601-1615页

作者： bo wu Xingbao Gao School of Mathematics and Statistics Ningxia UniversityYinchuan750021NingxiaChina School of Mathematics and Statistics Shaanxi Normal UniversityXi’an710062ShaanxiChina

This paper proposes a two-parameter block triangular splitting(TPTS)preconditioner for the general block two-by-two linear *** eigenvalues of the corresponding preconditioned matrix are proved to cluster around 0 or 1 under mild *** limited numerical results show that the TPTS preconditioner is more efficient than the classic block-diagonal and block-triangular preconditioners when applied to the flexible generalized minimal residual(FGMRES)method.

关键词： Block triangular splitting Block two-by-two linear systems Eigenvalues Preconditioner flexible generalized minimal residual(FGMRES)

Mini-LED,Micro-LED and OLED displays:present status and future perspectives

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Light(Science & Applications) 2020年第1期9卷 1009-1024页

作者： Yuge Huang en-Lin Hsiang Ming-Yang Deng Shin-Tson wu College of Optics and Photonics University of Central FloridaOrlandoFL 32816USA

Presently,liquid crystal displays(LCDs)and organic light-emitting diode(OLED)displays are two dominant flat panel display ***,inorganic mini-LEDs(mLEDs)and micro-LEDs(μLEDs)have emerged by significantly enhancing the dynamic range of LCDs or as sunlight readable emissive displays.“mLED,OLED,orμLED:who wins?”is a heated debatable *** this review,we conduct a comprehensive analysis on the material properties,device structures,and performance of mLED/μLED/OLED emissive displays and mLED backlit *** evaluate the power consumption and ambient contrast ratio of each display in depth and systematically compare the motion picture response time,dynamic range,and adaptability to flexible/transparent *** pros and cons of mLED,OLED,andμLED displays are analysed,and their future perspectives are discussed.

关键词： OLED heated transparent

Self-healing Hydrogelsand Underlying Reversible Intermolecular Interactions

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Chinese Journal of Polymer Science 2021年第10期39卷 1246-1261,I0005页

作者： Meng wu Qiong-Yao Peng Lin-bo Han Hong-bo Zeng Department of Chemical&Materials engineering University of AlbertaEdmontonAlberta T6G 1H9Canada College of Health Science and environmental engineering Shenzhen Technology UniversityShenzhen 518118China

Self-healing hydrogels have attracted growing attention over the past decade due to their biomimetic structure,biocompatibility,as well as enhanced lifespan and reliability,thereby have been widely used in various biomedical,electrical and environmental engineering *** feature article has reviewed our recent progress in self-healing hydrogels derived from mussel-inspired interactions,multiple hydrogen-bonding functional groups such as 2-ureido-4[1H]-pyrimidinohe(UPy),dynamic covalent bonds(eg,Schiff base reactions and boronic ester bonds).The underlying molecular basics of these interactions,hydrogel preparation principles,and corresponding performances and applications are *** underlying reversible intermolecular interaction mechanisms in these hydrogels were investigated using nanomechanical techniques such as surface forces apparatus(SFA)and atomic force microscopy(AFM),providing fundamental insights into the self-healing mechanisms of the *** remaining challenging issues and perspectives in this rapidly developing research area are also discussed.

关键词： Self-healing hydrogels Mussel-inspired Interaction Multiple hydrogen-bonding Dynamic covalent bonds Intermolecular forces