检索结果-南通市图书馆

Weak WT_2-class of differential forms and weakly A-harmonic tensors

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2010年第3期25卷 359-366页

作者： GAO Hong-ya wang yan-yan College of Mathematics and Computer Science Hebei University Baoding 071002 China Hebei Provincial Center of Mathematics Shijiazhuang 050016 China

In this paper, we give the definition of weak WT2-class of differential forms, and then obtain its weak reverse Holder inequality. As an application, we give an alternative proof of the higher integrability result of ... 详细信息

关键词： Weak WT2-class of differential forms weak reverse HSlder inequality weakly A-harmonic tensor,higher integrability.

Synthesis and Crystal Structure of a Coordination Polymer {[Co(phth)(phen)(H_2O)]·(C_2H_5OH)}_n

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2006年第10期25卷 1193-1196页

作者： GAO Ling CHENG Qing-yan wang yan-Ji Hebei University of Technology Tianjin 300130 China

The coordination polymer {[Co（phth）（phen）（H2O）]·（C2H5OH）}n （phth = phthalate, phen = 1,10-phenanthroline） with formula C22H2OCoN2O6 （Mr = 467.33） was synthesized by the solvothermal method under low temperature, and its crystal structure was determined by singlecrystal X-ray diffraction. The complex belongs to monoclinic system, space group P21/n with a = 12.7352（16）, b = 8.8125（11）, c = 18.677（2） °A, β= 102.633（2）°, V = 2045.3（4）°A^3 Z = 4, Dc= 1.518 g/cm^3,μ = 0.882 mm^-1, F（000） = 964, S = 1.053, the final R = 0.0401 and wR = 0.0984 for 3135 observed reflections （I〉 2σ（I））. Single-crystal X-ray analysis revealed that the Co（Ⅱ） ion is six-coordinated. The cobalt complex forms a one-dimensional chain structure via phthalate bridging ligand. In the cobalt complex, a 3D network structure is formed by π-π stacking interaction of 1,10-phenanthroline as well as intermolecular hydrogen bonding interactions.

关键词： cobalt complex solvothermal method π-π stacking hydrogen bond

Grid authentication from identity-based cryptography without random oracles

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 55-59页

作者： ZHENG yan wang Hai-yan wang Ru-chuan College of Computer Science Nanjing University of Posts and Telecommunications Nanjing 210003 China

As a critical component of grid security, secure and efficient grid authentication needs to be well addressed. However, the most widely accepted and applied grid authentication is based on public key infrastructure （PKI） and X.509 certificates, which make the system have low processing efficiency and poor anti-attack capability. To accommodate the challenge of grid authentication, this article aims at designing a secure and efficient method for grid authentication by employing identity-based cryptography （IBC）. Motivated by a recently proposed secure and efficient identity-based encryption （IBE） scheme without random oracles, an identity-based signature （IBS） scheme is first proposed for the generation of private key during grid authentication. Based on the proposed IBS and the former IBE schemes, the structure of a novel grid authentication model is given, followed by a grid authentication protocol described in detail. According to the theoretical analysis of the model and the protocol, it can be argued that the new system has improved both the security and efficiency of the grid authentication when compared with the traditional PKI-based and some current IBC-based models.

关键词： grid authentication security IBC scheme

QCM and EC-SPR Studies of Cytochrome c Self-assembled on Au Electrode and Enhancement of SPR Signal by Au Nanoparticles

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2012年第6期28卷 1061-1065页

作者： wang yan-yan JIANG yan-xla ZHOU You-chen LI yan-yan MA Zhi-fang SUN Shi-gang State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P. R. China

Quartz crystal microbalance（QCM） and cyclic voltammetry（CV） were used to characterize the monolayer of cytochrome c（Cyt c）,which was adsorbed on gold film modified with alkanethiol mixed monolayer.A direct comparison of protein surface coverages calculated from QCM and cyclic voltammetric measurements illustrates that the ratio of the electroactive Cyt c to the total surface-confined Cyt c is 34%,which suggests that the orientation is a main factor affecting the electroactivity of Cyt ***,surface plasmon resonance（SPR） measurement combined with CV ＂in situ＂ was used to investigate the conformational change of Cyt c in the redox ***,Au nanoparticles（Au NPs） were adsorbed on the surface of Cyt *** result indicates that Au NPs promote electron transfer between Cyt c and the gold electrode,and SPR result suggests Au NPs enhance SPR signal.

关键词： Cytochrome c Gold film Self-assembly Electrochemical-surface plasmon resonance(EC-SPR)

Catalysts for Hydration of Cyclohexene to Cyclohexanol

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2013年第4期29卷 743-746页

作者： FANG De-ren LU Jin-yan ZHANG Hui-min LI Jie wang yan-yan Shandong Provincial Key Lab of Chemical Engineering Institute of Applied Catalysis Yantai University Yantai 264005 P. R. China

The hydration of cyclohexene was determined in a stirred tank of 100 mL in a batch mode in the presence of modified or unmodified resin as catalyst. The ion-exchange sulfonate resin was modified with alkyl secondary amine. At an optimum amination rate of 15%, the conversion of cyclohexene reached to 22% and the selectivity of cyclohexanol was 95.6%. In a temperature range of 90--150℃, the activity and selectivity of the modified resin ca- talyst were much higher than those of the unmodified resin catalyst, which was attributed to the inclusion formed between cyclohexene and alkyl chain and also the quasi-lipophilic phase formed around the outer surface of resin beads. The formed quasi-lipophilic phase formed enhanced the conversion of cyclohexene and depressed the forma- tion of by-products.

关键词： Hydration Cyclohexene Ion-exchange resin Modification Aminate rate

Advanced Studies on Rhizoma Dioscoreae Collettii

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Integrative Medicine 2020年第3期26卷 235-240页

作者： LI Lai-lai MENG Xiao-wei FAN Ke-tao wang yan-yan XIAO yang wang Yi Institute of Traditional Chinese Medicine Research Tianjin State Key Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese Medicine

Rhizoma Dioscoreae Collettii,is known as Huang Dioscorea collettii,Rhizoma Coptidis Brevisepalae or yellow *** is neutral in nature and bitter in taste which is described to Gan(Liver)meridian,Wei(Stomach)meridian and Pangguang(Bladder)*** was often used in the treatment of chyloid stranguria,gonorrhea,leucorrhagia,rheumatism arthralgia pain,joints disable,and lumbar knee pain syndrome in clinical.

关键词： Rhizoma Dioscoreae Collettii identification chemical constituents pharmacology clinical application

Diamide derivatives containing a trifluoromethylpyridine skeleton:Design,synthesis,and insecticidal activity

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2022年第10期21卷 2995-3003页

作者： XU Fang-zhou wang yan-yan GUO Sheng-xin DAI A-li WU Jian State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering/Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education/Guizhou UniversityGuiyang 550025P.R.China

Diamide derivatives are biologically active molecules that have been widely applied in recent years in research on pesticides,especially *** a simple and environmentally friendly scheme,a series of new diamide derivatives containing a trifluoromethylpyridine skeleton was designed,synthesized,and confirmed by^(1)H,^(19)F and^(13)C NMR,and *** insecticidal activities against Plutella xylostella and Helicoverpa armigera were measured and the relationship between structure and activity was *** of the title compounds(D2,D5,D10,D21,D28,D29,D30 and D33)showed 100%activity against *** at 500 mg L^(-1).One compound,D33,still showed 100%activity against *** at 100 mg L^(-1)and had the lowest LC_(50)(lethal concentration 50%,3.7 mg L^(-1))among the synthesized *** docking analysis revealed that D33 could be thoroughly embedded in the active pocket of the ryanodine receptor via hydrogen bonding in a manner similar to the commercial insecticide chlorantraniliprole.

关键词： diamide derivatives trifluoromethylpyridine synthesis insecticidal activity molecular docking

Kinetic Phase Transition in A_2+2B_2→2B_2A Reaction System with Particle Diffusion

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2008年第4期49卷 960-964页

作者： HUA Da-Yin WENG Xiao-yan wang Lie-yan CHEN Ting Physics Department Ningbo University Ningbo 315211 China

A lattice gas model is presented for the A2 ＋2B2 → 2B2A reaction system with particle diffusion in two dimensions. In the model, B2 dissociates in the random dimer-filling mechanism and A2 dissociates in the end-on dimer filling mechanism. A reactive window appears and the system exhibits a continuous phase transition from a reactive state to a ＂B ＋ vacancy＂ covered state with infinitely many absorbing states. When the diffusion of particle B is considered, there are only two absorbing states. It is found that the critical behavior of the continuous phase transition changes from the directed percolation （DP） class to the pair contact process with diffusion （PCPD） class.

关键词： non-equilibrium phase transition reaction diffusion system

Investigation of Spontaneous Condensation of an Amino Acid Based Amphiphile on Cast Film by in situ Transmission FT-IR Spectroscopy

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2005年第12期16卷 1637-1640页

作者： Hai yan wang yan Mei LI Yi XIAO Yu Fen ZHAO The Key Laboratory of Bioorganic Phosphorus Chemistry ＆ Chemical Biology （Ministry of Education） Department of Chemistry Tsinghua University Beijing 100084

The spontaneous condensation of the amphiphilic N-（O,O-dihexadecyl）phosphorylalanine on the cast film was observed by in situ investigation of transmission infrared spectroscopy The particular orientation and ordered packing of the monomers within the multilayers of the cast film is concluded to attribute to the spontaneous condensation between the monomers.

关键词： Amphiphile cast film condensation FT-IR N-(O O-dihexadecyl)phosphoryl alanine