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A convenient catalytic oxidative 1,2-shift of arylalkenes for preparation of α-aryl ketones mediated by NaI

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Chinese Chemical Letters 2015年第2期26卷 248-250页

作者： Min Zhu Yang Zhao College of Biological and Environmental Sciences Zhejiang Shuren University Foreign Language School Zhejiang Shuren University

Using a catalytic amount of Nal and a stoichiometric oxidant Oxone-@,a convenient procedure has been developed for the catalytic oxidative 1,2-shift of arylalkenes in CH3CN/H2O at room temperature,which provides the corresponding α-aryl ketones in moderate to good *** this protocol,sodium iodide is first oxidized into hypoiodous acid,which reacts with arylalkene to afford ***,the iodohydrin is transformed into the α-aryl ketone via an oxidative 1,2-shift rearrangement.

关键词： Oxidative 1 2-shift α-Aryl ketone Sodium iodide Catalysis

Prediction of Infinite Dilution Activity Coefficients of Halogenated Hydrocarbons in Water

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Chinese Journal of Structural Chemistry 2008年第4期27卷 491-497页

作者：许惠英闵剑青 College of Biology & Environment Engineering Zhejiang Shuren University

Geometrical optimization and electrostatic potential calculations have been performed for a series of halogenated hydrocarbons at the HF/Gen-6d level. A number of electrostatic potentials and the statistically based structural descriptors derived from these electrostatic potentials have been obtained. Multiple linear regression analysis and artificial neural network are employed simultaneously in this paper. The result shows that the parameters derived from electrostatic 2 potentials σtot^2, V s and ∑ Vs^＋, together with the molecular volume （Vine） can be used to express the quantitative structure-infinite dilution activity coefficients （γ^∞） relationship of halogenated hydrocarbons in water. The result also demonstrates that the model obtained by using BFGS quasiNewton neural network method has much better predictive capability than that from multiple linear regression. The goodness of the model has been validated through exploring the predictive power for the external test set. The model obtained via neural network may be applied to predict γ^∞ of other halogenated hydrocarbons not present in the data set.

关键词： halogenated hydrocarbons molecular electrostatic potentials infinite dilution activity coefficients (γ^∞) QSPR artificial neural networks

Microwave Assistant Synthesis,Crystal Structure and Biological Activity of 1-(2-Fluorobenzyl)-3-methoxy-4-methyl-1H-1,2,4-triazol-5(4H)-one

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Chinese Journal of Structural Chemistry 2015年第11期34卷 1659-1664页

作者：雷超申屠超 College of Biology and Environmental Engineering Zhejiang Shuren University

The title compound 1-（2-fluorobenzyl）-3-methoxy-4-methyl-lH-1,2,4-triazol- 5（4H）-one （CI1HI2FN302） was synthesized, and its structure was confirmed by 1H NMR, IR, MS, elemental analysis and X-ray diffraction. It crystallizes in the monoclinic system, space group Pi with a = 6.919（3）, b = 8.525（4）, c = 9.811（4） A, a = 84.22（2）, β = 71.028（19）, γ = 86.10（2）°, Dc = 1.448 g/cm3, Z = 2, V= 544.2（4） A3, F（000） = 248, the final R = 0.0379 and WR = 0.0913 for 1709 observed reflections with I〉 2σ（I）. The preliminary biological test shows that the title compound shows weak inhibitory activities against Phytophthora infestans, Botrytis cinerea, Corynespora cassiicola, Rhizoctonia solani and Pythium ultimum.

关键词： 1,2,4-triazole synthesis crystal structure fungicidal activities

Surface Electrostatic Potentials of Polychlorinated Dibenzo-p-dioxins and Their Applications in the Quantitative Structure-properties Relationships

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Chinese Journal of Structural Chemistry 2011年第6期30卷 793-798页

作者：许惠英王维柴水英 College of Biology & Environment Engineering zhejiang shuren university Center of Modern Education Technology Zhejiang Shuren University Zhenhai Environmental Monitoring Station

Polychlorinated dibenzo-p-dioxins（PCDDs） are a group of important persistent organic *** are highly toxic and persistent in *** the present study,geometrical optimization and electrostatic potential calculations have been performed for 75 PCDD congeners and dibenzo-p-dioxin（DD） at the HF/6-31G＊ level of theory.A number of statistically based parameters have been *** relationships between vapor pressures（logpL）,aqueous solubilities（logSw）,n-octanol/water partition coefficients（logKow） of PCDDs and structural descriptors have been established by stepwise linear regression *** result shows that the quantities derived from the surface electrostatic potentials Vmin,Π,and Vs,av＋,together with Vmc（the molecular volume） and ELUMO（the energy of the lowest unoccupied molecular orbital） can be well used to express the quantitative structure-property relationships of *** capabilities of the models have also been demonstrated by leave-one-out cross-validation with the cross-validated correlation coefficient（Rcv） above *** on these QSPR models,the predicted values have been presented for those PCDD congeners whose experimentally determined physicochemical properties are unavailable.

关键词： QSPR polychlorinated dibenzo-p-dioxin molecular electrostatic potential

Investigation of the Substituent Effects on π-Type Pnicogen Bond Interaction

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Chinese Journal of Structural Chemistry 2018年第3期37卷 356-366页

作者：许惠英曹生炜王维朱建清邹建卫许晓路陆胤 College of Biology & Environment Engineering Zhejiang Shuren University zhejiang Linix Motor CO. LTD zhejiang Surveying Institute of Estuary and Coast Department of Basic Courses Zhejiang Shuren University Ningbo Institute of Technology Zhejiang University

Intermolecular interactions between PH2Cl and Ar–R（R = H,OH,NH2,CH3,Br,Cl,F,CN,NO2） were calculated by using MP2/aug-cc-p VDZ quantum chemical *** has been shown from our calculations that the aromatic rings with electron-withdrawing groups represent much weaker binding affinities than those with electron-donating *** charge-transfer interaction between PH2Cl and Ar–R plays an important role in the formation of pnicogen bond complexes,as revealed by NBO ***,AIM analysis shows that the nature of the interactions between PH2Cl and Ar–R is electrostatic,and the interaction energies of the complexes are correlated positively with the electron densities in the bond critical points（BCPs）.RDG/ELF graphical analyses were performed to visualize the positions and strengths of the pnicogen bonding,as well as the spatial change of the electron localization upon the formation of *** π-type halogen bond was also calculated,and it has been revealed that the π-type pnicogen bond systems are more stable than the halogen bond ones.

关键词： π-type pnicogen bonding π-type halogen bonding NBO AIM RDG/ELF analysis

Separation of Aromatic Carboxylic Acids in IC and the Study on the Relationship Between Retention Behavior and Electrostatic Potential

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Chinese Journal of Structural Chemistry 2010年第4期29卷 641-646页

作者：王艳花韩小江陈雪松李立朱岩 College of Biology and Environment Engineering Zhejiang Shuren University Department of Chemistry Zhejiang University

A method has been developed for separation of 20 kinds of aromatic carboxylic acid using anion-exchange chromatography. A Dionex IonPac AS9-HC guard column （250mm×2mm） was used with a 9mmol/L sodium carbonate solution containing 50% （v/v） acetonitrile as eluent. A set of retention time data has been obtained using a conductivity detector DS6. Furthermore, geometrical optimization and electrostatic potential calculation of 20 kinds of aromatic carboxylic acid have been performed at the HF/6-31G＊ level of theory. A number of statistically-based parameters derived from molecular surface electrostatic potential have been obtained. Linear relationship between retention time and structural parameters has been established by multiple regression method. The result shows that parameters derived from electrostatic potential Vs ＋, Vs -, П together with the dipole moment μ can be well used to express the quantitative structure-retention time of this kind of aromatic carboxylic acid. Good predictive capability has also been demonstrated. The result has provided a framework which further proves the general applicability of this electrostatic potential parameter set to a great extent,and with which the ion chromatographic adsorption mechanism can be investigated.

关键词： Ion chromatography Retention time QSRR molecular electrostatic potential aromatic carboxylic acid

An Energy Efficient MAC Protocol for Linear WSNs

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Chinese Journal of Electronics 2015年第4期24卷 725-729页

作者： DAI Guoyong MIAO Chunyu YING Kezhen WANG Kai CHEN Qingzhang College of Computer Science and Technology Zhejiang University of Technology College of Information Science and Technology Zhejiang Shuren University

Wireless sensor networks(WSNs) have been employed as an ideal solution in many applications for data gathering in harsh environment. Energy consumption is a key issue in wireless sensor networks since nodes are often battery operated. Medium access control(MAC) protocol plays an important role in energy efficiency in wireless sensor networks because nodes’ access to the shared medium is coordinated by the MAC layer. An energy efficient MAC protocol is designed for data gathering in linear wireless sensor networks. In order to enhance the performance, when a source node transmits data to the sink, proper relay nodes are selected for forwarding data according to the energy consumption factor and residual energy balance factor. Some simulation experiments are conducted and the results show that, the proposed protocol provides better energy efficiency and long lifetime than the existing DMAC protocol.

关键词： WSN Linear topology MAC protocol Low-energy consumption Relay nodes

A method of shadow puppet figure modeling and animation

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Frontiers of Information Technology & Electronic Engineering 2015年第5期16卷 367-379页

作者： Xiao-fang HUANG Shou-qian SUN Ke-jun ZHANG Tian-ning XU Jian-feng WU Bin ZHU College of Computer Science and Technology Zhejiang University School of Art Zhejiang University of Technology College of Information Science and Technology Zhejiang Shuren University

To promote the development of the intangible cultural heritage of the world, shadow play, many studies have focused on shadow puppet modeling and interaction. Most of the shadow puppet figures are still imaginary,spread by ancients, or carved and painted by shadow puppet artists, without consideration of real dimensions or the appearance of human bodies. This study proposes an algorithm to transform 3D human models to 2D puppet figures for shadow puppets, including automatic location of feature points, automatic segmentation of 3D models, automatic extraction of 2D contours, automatic clothes matching, and animation. Experiment proves that more realistic and attractive figures and animations of the shadow puppet can be generated in real time with this algorithm.

关键词： Shadow play Shadow puppet figure 3D human body Data processing 2D modeling

QSPR Analysis of the Physicochemical Properties for Phthalic Acid Esters

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1880-1884页

作者： XU Hui-Ying SHU Tian-Ge WANG Wei ZHU Jian-Qing LU Yin XU Xiao-Lu WU Gang College of Biology & Environment Engineering Zhejiang Shuren University Zhenhai Environmental Monitoring Station Department of Basic Courses Zhejiang Shuren University Shaoxing university

Based on quantitative structure-property relationship （QSPR） of organic compounds, the molecular connectivity indices of 21 phthalic acid ester compounds were extracted. Relationship between the physicochemical properties （n-octanol/air partition coefficient, vapor pressure, water solubility） and the molecular connectivity indices of phthalic acid ester compounds have been established by multiple linear regression （MLR） method. The results showed that the zero-order valence connectivity index （0Xu） is the topology parameter which affects octanol/water partition coefficient and water solubility, and the topology parameter which affects vapor pressure is the first-order connectivity index （1X）. This indicated to a certain extent_that the molecular connectivity indices can be well used to express the quantitative relationship between the physicochemical properties and structure descriptions of phthalic acid ester compounds. The models constructed have good robustness and highly predictive capability.

关键词： phthalic acid esters molecular connectivity index,physicochemical property QSPR