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Synthesis　and　Amphiphilic　Characteristics　of　8－Hydroxyquinoline　with　Alkyl　Chain

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Chinese Chemical Letters 1996年第9期7卷 807-808页

作者： Jian Ming OUYANG Chao Yang JIANG Zi Hou TAI Wen Xia TANG(state key laboratory of coordination Chemisty, nanjing university,nanjing,210093) state key Lab. of Coord. chemistry Nanjing University Nanjing 210093

The amphiphilic derivatives of 8-hydroquinoline with alkyl chain have been *** derivatives can form stable monolayer on pure water and an aqueous subphase containing Metal ions.

关键词： Hydroxyquinoline Characteristics Alkyl

DNA Cleavage by Copper (Ⅱ) Complexes Without added Coreactants

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Chinese Chemical Letters 1999年第5期10卷 383-386页

作者： Rui REN Pin YANG Gao Yi HAN(Institute of coordination chemistry. state key laboratory of coordination chemistry.nanjing university. nanjing 210093Institute of Molecular Science. Shanxi university. Taiyuan 030006) Institute of coordination chemistry State Key Lab. of Coord. Chemistry Nanjing University Nanjing 210093 China Institute of Molecular Science Shanxi University Taiyuan 030006 China

The cleavage activity of complexes between copper (Ⅱ) and four different amino acidor amino acid methyl ester on DNA was tested at physioloical pH and temperature., It was found that Cu (Ⅱ)-L-His and Cu (Ⅱ)-L-His methyl ester complexes could cleane DNA. The extent ofDNA cleavage is largely dependent on the metal ion-to-ligand ratio. The cleavage of doublestranded DNA mediated by Cu (Ⅱ)-L-His complexes occurs via a hydrolytie mechanism.

关键词： Copper (Ⅱ) complexes DNA hydrolytic cleavage

Crystal Structure and Third-order Nonlinear Optical Property Studies on Copper(Ⅱ) Complex Containing NS Donor Ligand

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Chinese Chemical Letters 1998年第7期9卷 691-693页

作者： Fu Xin XIE Yu Peng TIAN Shi Sheng NI (Department of chemistry, Anhui university, Hefei 230039)(state key laboratory of coordination chemistry, nanjing university, Naning 210093) Anhui Univ Dept Chem Hefei 230039 Peoples R China nanjing Univ State Key Lab Coordinat Chem Nanjing 210093 Peoples R China

A novel Schiff base ligand (HL) derived from S-methyldithiocabazate and pmethoxylbenzaldehyde was prepared and characterized. The Schiff base ligand acts as a single negatively charged bidentate ligand fondng D-M-D type comPlex (D=donor, M=metal). Single crystal X-ray diffraction analysis of the copper(Ⅱ) complex established that the geometry around Cu (Ⅱ) is square-planar with two equivalent M-N and M-S bonds. The two phenyl rings and the coordinated plane are almost in one plane fotheng an electronic delocalization system. Their thirdorder response was also studied.

关键词： copper (Ⅱ) complex third-order nonlinear optical property NS donor ligand

Differential AR algorithm for packet delay prediction

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Progress in Natural Science:Materials International 2006年第4期16卷 437-440页

作者： JIAO Liangbao, ZHANG De and BI Houjie Institute of Acoustics, state key laboratory of Modern Acoustics, nanjing university, nanjing 210093, china Institute of Communication Technique, nanjing university, nanjing 210093, china Institute of Acoustics State Key Laboratory of Modern Acoustics Nanjing University Nanjing 210093 China Institute of Communication Technique Nanjing University Nanjing 210093 China

Different delay prediction algorithms have been applied in multimedia communication, among which linear prediction is attractive because of its low complexity. AR (auto regressive) algorithm is a traditional one with low computation cost, while NLMS (normalize least mean square) algorithm is more precise. In this paper, referring to ARIMA (auto regression integrated with moving averages) model, a differential AR algorithm (DIAR) is proposed based on the analyses of both AR and NLMS algorithms. The prediction precision of the new algorithm is about 5-10 db higher than that of the AR algorithm without increasing the computation complexity. Compared with NLMS algorithm, its precision slightly improves by 0.1 db on average, but the algorithm complexity reduces more than 90% . Our simulation and tests also demonstrate that this method improves the performance of the average end-to-end delay and packet loss ratio significantly.

关键词： AR algorithm NLMS algorithm differential AR algorithm ARIMA model.

Syntheses, properties and structures of copper and nickel complexes of 6,7-dihydro-5H-1,4-dithiepin-2,3-dithiolate

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Chinese Journal of chemistry 1994年第3期12卷 248-257页

作者： YAO, Tian-Ming YOU, Xiao-Zengcoordination chemistry Institute, state key laboratory of coordination chemistry, nanjing university,nanjing 210008, chinaYANG, Qing-Chuanchemistry Department, Beijing university, Beijing 100871, china coordination chemistry Institute State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210008 China chemistry Department Beijing University Beijing 100871 China

The reaction of CuCl2-2H2O or NiCl2.6H2O with K2(C5H6S4) [potassium salt of 6,7-dihydro-5H-1,4-dithiepin-2,3-dithiolate] under nitrogen atmosphere resulted in the isolation of [Cu(C5H6S4)2]- or [Ni(C5H6S4)2]- as the tetrabutylammonium salt. Both complexes show characteristic IR and UV-Vis absorptions of transition metal dithiolenes. Cyclic voltammograms contain two waves indicating a two step electrochemical procedure [M(C5H6S4)2]0 = [M(C5H6S4)2]1-= [M(C5H6S4)2]2-. Single crystal structure study has been carried out on the nickel complex. Crystal of [Bu4N][Ni(C5H6S4)2] belongs to monoclinic space group P21/c with a=17.576(5), 6=10.883(2), c=17.773(4) A,B=91.07(2)0, Z=4, and o(calcd.)=1.348 g/cm3. Final result is R=0.059 for 2959 reflections. The NiS4 core exhibits square planar coordination with average Ni-S bond length of 2.134(5) A. There are not anion pairs in crystal. The anions stack along a and c axes while the cations intercalate in them. The nearest S-S contact is 4.429 A. The solid powder ESR spectrum of the nickel complex shows three broadening signals at g1=2.097, g2=2.042, g3=2.022. Magnetic susceptibility data for [Bu4N][Ni(CgH6S4)2] reveal enhanced anti-ferromagnetic interaction.

关键词： Dithiolene complex copper nickel single crystal.

A local spin evaluation into the active site models of [2Fe2S] ferrodoxin [Fe_2S_2(SR)_4]^(2-) (R=-H, -CH_3)

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Science china chemistry 2007年第3期50卷 327-334页

作者： WEI JiChong1,2, WANG Yan3 & JU GuanZhi2,3 1 Department of chemistry, Hainan Normal university, Haikou 571158, china 2 state key laboratory of Theoretical and Computational chemistry, Jilin university, Changchun 130023, china 3 Department of chemistry, nanjing university, nanjing 210093, china Department of chemistry Hainan Normal University Haikou China state key laboratory of Theoretical and Computational chemistry Jilin University Changchun China Department of chemistry Nanjing University Nanjing China

To test the feasibility of local spin theory of Davidson and Clark for ferrodoxin clusters, the models [Fe2S2(SR)4]2- (R=-H, -CH3) are chosen for evaluation. This purpose is realized by calculating the local spin expectation values , 2 >, and mA and discussing the connection between these expected values and the Heisenberg spin model (HSM) and the Noodleman broken-symmetry approach. In practical calculation, the spin-unrestricted Hartree-Fock (UHF) and spin-polarized density functional theory (DFT) are used and the calculational qualities of these two methods are also discussed. In addition, the theoretical magnetic coupling constants JAB of these models are calculated by various computational schemes for comparison with both theoretical and experimental results previously reported.

关键词： local spin iron-sulfur protein model density function theory magnetic coupling constant

Design, Synthesis and Characterization of a Novel Schiff Base Bis(iminoantipyrine) and Its Modified Electrode

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Chinese Chemical Letters 1998年第3期9卷 245-248页

作者： Jin Gang Liu Fu Xin Xie Sheng Yi Zhang Yu Peng Tian Shi Sheng Ni(Department of chemistry, Anhui university,Hefei 230039)(coordination chemistry state key laboratory of nanjing university, nanjing 210093) Department of chemistry Anhui University Hefei 230039 China

A novel Schiff base, N,N-bis[2-(2-iminoantipyrinephenoxy)ethyl]-p-toluenesulfonamide (BIAET), was synthesized and characterized, and a carbon paste electrode modified with BIAET was prepared and employed for quantitat... 详细信息

关键词： synthesis lead(II)complex modified electrode

Preparation and Characterization of Nanocomposite MgFe_2O_4/SiO_2

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Journal of Wuhan university of Technology(Materials Science) 2009年第3期24卷 354-358页

作者：徐莉 College of Science Nanjing Forestry University

Nanocomposites MgFe2O4/SiO2 were successfully synthesized by the sol-gel method in the presence of N, N-dimethylformamide （DMF）. The formation of pure MgFe2O4 was confirmed by powder X-ray diffraction （XRD） and electron diffraction. The structural evolution of MgFe2O4 nanocrystals was followed by powder X-ray diffraction and IR absorption spectroscopy. The formation of spinel structure of MgFe2O4 started at 800 ℃, and completed at 900 ℃, The transmission electron microscopy （TEM） measurements suggest that the particle sizes increase with the increasing annealing temperature, and the mean particle sizes of the spherical samples annealed at 800 ℃, 900 ℃ and 1 050 ℃ are ca. 3 nm, 8 nm and 11 nm, respectively. Magnetization measurements at room temperature and 78 K indicate supemaramagnetic nature of these MgFe2O4 nanocrvstals.

关键词： nanocomposite sol-gel magnesium ferrite magnetic property

Predicting MDCK cell permeation coefficients of organic molecules using membrane-interaction QSAR analysis

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Acta Pharmacologica Sinica 2005年第11期26卷 1322-1333页

作者： Li-li CHEN, Jia YAO, Jian-bo YANG, Jie YANG~2 state key laboratory of Pharmaceutical Biotechnology, College of Life Sciences, nanjing university, nanjing 210093, china state key laboratory of Pharmaceutical Biotechnology College of Life Sciences Nanjing University Nanjing China

Aim: To use membrane-interaction quantitative structure-activity relationship analysis (MI-QSAR) to develop predictive models of partitioning of organic compounds in gastrointestinal cells. Methods: A training set of 22 structurally diverse compounds, whose apparent permeability accross cellular membranes of Madin-Darby canine kidney (MDCK) cells were measured, were used to construct MI-QSAR models. Molecular dynamic simulations were used to determine the explicit interaction of each test compound (solute) with a dimyristoyl-phosphatidyl-cho-line monolayer membrane model. An additional set of intramolecular solute descriptors were computed and considered in the trial pool of descriptors for building MI-QSAR models. The QSAR models were optimized using multidimensional linear regression fitting and the stepwise method. A test set of 8 compounds were evaluated using the MI-QSAR models as part of a validation process. Results: MI-QSAR models of the gastrointestinal absorption process were constructed. The descriptors found in the best MI-QSAR models are as follows: 1) ClogP (the logarithm of the 1-octanol/water partition coefficient); 2) EHOMO(the highest occupied molecular orbital energy); 3) Es(stretch energy); 4) PMY(the principal moment of inertia Y, the inertia along the y axis in the rectangular coordinates; 5) C,(total connectivity); and 6) Enb(the energy of interactions between all of the non-bonded atoms). The most important descriptor in the models is ClogP. Conclusion: Permeability is not only determined by the properties of drug molecules, but is also very much influenced by the molecule-membrane interaction process.

关键词： quantitative structure-activity relationship molecular models organic chemicals artificial membranes cell membrane permeability MDCK cells