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Research on the Key Issues of Wireless Mobile Ad Hoc Networks

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The Journal of China Universities of Posts and Telecommunications 2005年第3期12卷 1-6页

作者： YANG Zhen zheng bao-yu Nanjing University of Posts & Telecommunications Nanjing 210003 P.R. China

Communication Network and Signal Processing are two of the research hotspots in the field of information technology because of their fast development. This paper focuses on the introduction of some research progresses in our National 863 Project based on the combination of technologies in these two areas. We present two new Medium Access Control （MAC） protocols based on so-called Multi-Packets Reception （MPR） in Ad hoc networks. Communication in the first scheme is initiated from senders and from receivers in the second one. Simulation results show that these new MAC protocols, which are based on new signal processing techniques, may raise network capacity and reduce transmission delay of data from end to end.

关键词： Ad hoc MAC MPR

Syntheses and Biological Activities of Ethyl N-Hydroxy-N-(substituted)phenyloxamates as KARI Inhibitors

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Chemical Research in Chinese Universities 2007年第3期23卷 280-283页

作者： WANG bao-lei LI zheng-ming LI Yong-hong WANG Su-hua Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

Nine ethyl N-hydroxy-N-（substituted） phenyloxamates （2a-2i）, based on the structure of the KARI inhibitor IpOHA, were synthesized. Their structures were established on the bases of 1^H NMR, IR, ESI-MS and elemental analyses. Among the nine compounds, four show in vitro inhibitory activity on rice KARI, with 2c and 2g[ Ki values of （35.2±4.9） and （49.4 ±6. 3） μmol/L] having similar activity to the precursor of IpOHA（A, Ki =34. 1±6. 7 μmol/L）. The results will be helpful to further molecular design of more potent KARI inhibitors.

关键词： KARI inhibitor IpOHA Phenyloxamate Synthesis Biological activity

Role of transforming growth factor-beta signaling pathway in pathogenesis of benign biliary stricture

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World Journal of Gastroenterology 2008年第31期14卷 4949-4954页

作者： Zhi-Min Geng Jian-bao zheng Xiao-Xue Zhang Jie Tao Lin Wang Department of Hepatobiliary Surgery First Affiliated Hospital Medical College Xi'an Jiaotong University Xi'an 710061. Shaanxi Province China Department of General Surgery Firs Affiliated Hospital Medical College Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China

AIM: To characterize the expression of members of the transforming growth factor-beta (TGF-β)/Smad/ connective tissue growth factor (CTGF) signaling pathway in the tissue of benign biliary stricture, and to investigate the effect of TGF-β signaling pathway in the pathogenesis of benign biliary stricture. METHODS: Paraffin embedded materials from 23 cases of benign biliary stricture were analyzed for members of the TGF-β/Smad/CTGF signaling pathway. TGF-β_1, TβRⅠ, TβRⅡ, Smad4, Smad7 and CTGF protein were detected by immunohistochemical strepto-advidinbiotin complex method, and CTGF mRNA was evaluated by hybridization in situ, while 6 cases of normal bile duct served as controls. The percentages of positive cells were counted. The correlation between TGF-β_1, Smad4 and CTGF was analyzed. RESULTS: The positive expression ratios of TGF-β_1, TβRⅠ , TβRⅡ , Smad4, CTGF and CTGF mRNA in 23 cases with benign biliary stricture were 91.3%, 82.6%, 87.0%, 78.3%, 82.6% and 65.2%, respectively, signifi cantly higher than that in 6 cases of normal bile duct respectively (vs 33.3%, 16.7%, 50.0%, 33.3%, 50.0%, 16.7%, respectively, P 0.05). There was a positive correlation between positive expression of TGF-β_1, Smad4 and CTGF in cases with benign biliary stricture. CONCLUSION: The high expression of TGF-β/Smad/ CTGF signaling pathway plays an important role in the pathogenesis of benign biliary stricture.

关键词： Biliary stricture Transforming growth factor-beta 1 Smad Connective tissue growth factor TβR

Data Security and Privacy in Bitcoin System:A Survey

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Journal of Computer Science & Technology 2020年第4期35卷 843-862页

作者： Lie-Huang Zhu bao-Kun zheng Meng Shen Feng Gao Hong-Yu Li Ke-Xin Shi School of Computer Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Information Management for Law China University of Political Science and LawBeijing 102249China Key Laboratory of Information Network Security Ministry of Public SecurityShanghai 201204China

To date,bitcoin has been the most successful application of blockchain technology and has received considerable attention from both industry and *** is an electronic payment system based on cryptography rather than on *** of whether people are in the same city or country,bitcoin can be sent by any one person to any other person when they reach an *** market value of bitcoin has been rising since its advent in 2009,and its current market value is US160 *** its development,bitcoin itself has exposed many problems and is facing challenges from all the sectors of society;therefore,adversaries may use bitcoin's weakness to make considerable *** survey presents an overview and detailed investigation of data security and privacy in bitcoin *** examine the studies in the literature/Web in two categories:1)analyses of the attacks to the privacy,availability,and consistency of bitcoin data and 2)summaries of the countermeasures for bitcoin data *** on the literature/Web,we list and describe the research methods and results for the two *** compare the performance of these methods and illustrate the relationship between the performance and the ***,we present several important open research directions to identify the follow-up studies in this area.

关键词： security privacy bitcoin availability consistency

EXTERNAL BODY FORCEIN FINITE DIFFERENCE LATTICE BOLTZMANN METHOD

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Journal of Hydrodynamics 2005年第4期17卷 473-477页

作者： CHEN Sheng LIU Zhao-hui SHI bao-chang zheng Chu-guang State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 China

A new finite difference lattice Boltzmann scheme is developed. Because of analyzing the influence of external body force roundly, the correct Navier-Stokes equations with the external body force are recovered, without any additional unphysical terms. And some numerical results are presented. The result which close agreement with analytical data shows the good performance of the model.

关键词： Finite Difference Lattice Boltzmann Method (FDLBM) body force

A Method of Designing Irregular Subarray Architectures for Partially Adaptive Processing

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A Method of Designing Irregular Subarray Architectures for P...

Photoredox-Catalyzed Metal-Free Regio-&Stereoselective C(sp^(2))-H Amination of Enamides with N-Aminopyridium Salts

1996 CIE International Conference of Radar(ICR’96)

作者： Xu Zhiyong bao zheng Liao Guisheng Key Laboratory for Radar Signal Processing Xidian University

ISBN: (纸本)0780329147

＜正＞A method of dividing a uniform linear array with identical elements into unequally sized subarrays is proposed on the principle of designing a density tapering *** power at every subarray output is normalized for partially adaptive processing to obtain near-optimum interference suppression performance with low sidelobe level and distonionless mainlobe in adapted antenna *** regular subarray architectures, irregular subarray architectures may have no problem of grating *** example of space-time adaptive processing（STAP）for airborne radar systems based on irregular subarrays is given.

关键词： interference suppression airborne radar radar interference adaptive antenna arrays radar antennas adaptive signal processing radar signal processing linear antenna arrays antenna radiation patterns design irregular subarray architectures partially adaptive processing uniform linear array w unequally sized subarray density tapering array noise power subarray output near-optimum interference suppression performance sidelobe level distortionless mainlobe adapted antenna pattern grating lobes space-time adaptive processing STAP airborne radar systems

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Chinese Journal of Chemistry 2024年第18期42卷 2235-2242页

作者： zheng-bao Qin Kun Ni Li Wang Xiao-Di Wu Yu Zhang Kai Zhao Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjingJiangsu211816China college of Chemical Engineering Nanjing Forestry UniversityNanjingJiangsu 210037China

A visible-light-induced photoredox-catalyzed regioselective and stereoselective C(sp')-H amination of enamides with bench-stable and A visible-light-induced photoredox-catalyzed regioselective and stereoselective C(sp)-H amination of enamides with bench-stable and easily accessible N-aminopyridium salts is developed,affording synthetically and biologically prominent vicinal 1,2-diamine scaffolds with broad substrate scope and excellent functional group *** transformation proceeded through a radical pathway involving the Giese addition of the relatively electrophilic N-centered sulfonamidyl radical species to nucleophilicβ-olefinic position of enamides followed by the ensuing single electron oxidation andβ-H elimination,delivering geometrically-defined Z-configuredβ-sulfonamidylated *** operational simplicity,environmental friendliness and cost efficiency of this methodology allowed it to pave a new avenue to enrich the arsenal of synthetically crucial functionalized enamides and their related derivatives.

关键词： Enamides Amination Photoredox catalysis Regioselective Stereoselective Metal-free

Fluorescence Properties of Porphyrin Dimers Incorporating an Anhydride Linker

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Chemical Research in Chinese Universities 2006年第6期22卷 684-687页

作者： FA Huan-bao YIN Wei zheng Wen-qi LI Di SHAN Ning WANG Xing-qiao College of Chemistry Jilin University Changchun 130023 P. R. China

A preliminary study on a novel free base porphyrin dimer and a zinc prophyrin dimer by comparing their fluorescence properties with those of the corresponding monomers is presented. The fluorescence intensity of the free base dimer is five times higher than that of the monomer, but the fluorescence intensity of the zinc porphyrin dimer is nearly similar to that of the zinc porphyrin monomer. The emission spectra show that energy transfer occurs between the two units.

关键词： Porphyrin dimer Zinc dimer Fluorescence property

Synthesis and Crystal Structure of 5-N-i-Propyl-2-(2′-nitrobenzenesulfonyl)-glutamine

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Chemical Research in Chinese Universities 2006年第6期22卷 760-762页

作者： XIAO Yong-jun WANG Jian-guo WANG bao-lei LI zheng-ming SONG Hai-bin Elemento-Organic Chemistry Institute State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

The title compound, 5 -N-i-propyl-2-（2＇ -nitrobenzenesulfonyl）-glutamine, was synthesized and its structure was confirmed by IB, MS, ^1H NMB, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P2（ 1 ）, with a =0. 69281 （ 11 ） nm, b = 0. 76508（12）, c = 1. 5843（3） nm, α=90°, β =90. 941 （3）°, γ =90°, V=0. 8397（2） nm^3, Z =-2, Dc = 1.477 g/cm^3,μ =0. 236 mm^-1, F（000） =392, R =0. 0297, and wR=0.0664.

关键词： 5 -N-i-Propyl-2-( 2' -nitrobenzenesulfonyl) -glutamine Synthesis Crystal structure