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Computational Simulation and Electrochemically Deposited Molecularly Imprinted Polymer-coated Carbon Glass Electrode for Triclosan Detection

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1252-1260页

作者： GAO Bo tang shan-shan LIU Jun-Bo JIN Rui-fa College of Resources and Environment Jilin Agricultural UniversityChangchun 130118China College of Chemistry and Chemical Engineering Chifeng UniversityChifeng 024000China

Triclosan,a kind of multi-purpose biocide,was widely used household cleaning and personal care *** widespread use of triclosan has potential risk to the ecotype and human health due to its release into sediment,surface and ground water resources.A molecularly imprinted electrochemical sensor for triclosan detection in cosmetic emulsion was synthesized and *** order to determine the suitable monomer and evaluate the template-monomer geometry as well as the interaction energy in the template-monomer prepolymerization mixture,a computational study was *** found that the complex formed by hybrid monomers(triclosan(o-phenylenediamine-co-resorcinol))had more hydrogen bonds and larger binding energy than that by single kind of monomers(triclosan(o-phenylenediamine)2 and triclosan(resorcinol)2).Therefore,hybrid monomers were used to synthesize the imprinted electrochemical sensor,which exhibits a high sensitivity and selectivity for triclosan sensing with the detection range 0~15 ng·mL-1 and detection limit 0.41 ng·mL-1.

关键词： computational simulation electrochemical synthesis molecular imprinting triclosan hybrid monomers

Multilinear Fractional Hausdorff Operators

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Acta Mathematica Sinica,English Series 2014年第8期30卷 1407-1421页

作者： Da shan faN fa You ZHAO Department of Mathematical Sciences University of Wisconsin-Milwaukee Department of Mathematics Shanghai University

In this paper,by introducing the space with weak mixed norms,weak type estimates of two kinds of multilinear fractional Hausdorff operators RΦ,β and SΦ,β on Lebesgue spaces are *** virtue of Marcinkiewicz interpolation,strong type estimates of these two operators on Lebesgue spaces are also *** methods shed some new light on dealing with the case of non-radial function Φ.

关键词： Multilinear fractional Hausdorff operators bilinear fractional Hardy operator weak type,strong type

EXPANSIONS OF STEP-TRANSITION OPERATORS OF MULTI-STEP METHODS AND ORDER BARRIERS FOR DAHLQUIST PAIRS

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Journal of Computational Mathematics 2006年第1期24卷 45-58页

作者： Quan-dong Feng Yi-fa tang LSEC ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China Graduate School of the Chinese Academy of Sciences Beijing 100080 China

Using least parameters, we expand the step-transition operator of any linear multi-step method （LMSM） up to O（τ^s＋5） with order s = 1 and rewrite the expansion of the steptransition operator for s = 2 （obtained by the second author in a former paper）. We prove that in the conjugate relation G3^λτ o G1^τ =G2^τ o G3^λτ with G1 being an LMSM,（1） theorder of G2 can not be higher than that of G1; （2） if G3 is also an LMSM and G2 is a symplectic B-series, then the orders of G1, G2 and G3 must be 2, 2 and 1 respectively.

关键词： Linear Multi-Step Method Step-Transition Operator B-series Dahlquist(Conjugate) pair Symplecticity

SYSTHESIS OF DOUBLE-HYDROPHILIC CORE-SHELL TYPE MULTIARM STAR COPOLYMER POLYETHYLENIMINE-block-POLY(2-HYDROXYETHYL METHACRYLATE)

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Chinese Journal of Polymer Science 2013年第7期31卷 1046-1055页

作者： Qiang tang fa Cheng Jin Cui 陈宇 School of Chemical and Environmental Engineering Hubei University of Technology Department of Chemistry School of SciencesTianjin University National Foodstuff Inspection Center Tianjin Product Quality Inspection Technology Research Institute

Multiarm star block copolymers hyperbranched polyethylenimine-b-poly（2-hydroxyethyl methacrylate）（HPEI-b- PHEMA） with average 28 PHEMA arms have been prepared by atom transfer radical polymerization （ATRP） of HEMA in a mixed solvent of methanol and water using a core-first strategy. The hyperbranched macroinitiator employed was prepared on the basis of well-defined hyperbranched polyethylenimine with Mw/Mn of 1.04 by amidation with 2-bromo-isobutyryl bromide. The polymerization condition was optimized to prepare star copolymers with narrow dispersity, and the variables included the volume ratio of methanol to water, the molar ratio of initiating site to CuC1 and the molar ratio of [CuCl]：[CuBr2]. Under the optimized polymerization condition, the lowest Mw/Mn value of the obtained star copolymers was around 1.3. Kinetic analysis showed that an induction period existed in the polymerization of HEMA. After this induction period, a linear dependence of ln（[M]0/[M]t） on time was observed. The obtained HPEI-b-PHEMA could adsorb hydrophilic molecules. The comparison with the star copolymer with hydrophobic core and hydrophilic PHEMA shell verified that both the hydrophilic core and shell could host the hydrophilic guests, but the amidated HPEI core was more effective than the PHEMA shell.

关键词： Atom transfer radical polymerization Hyperbranched Polyethylenimine Poly(2-hydroxyethyl methacrylate) Star polymers.

A Finite Element Based Study on Lowering Operation of Subsea Massive Structure

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China Ocean Engineering 2017年第5期31卷 646-652页

作者： WANG fa-cheng WANG Jun tang Ke Department of Civil Engineering Tsinghua University COTEC Offshore Engineering Solutions

Subsea production system has been increasingly used in recent South China Sea offshore developments. With deepwater applications, constituent parts of subsea systems become more complicated and enlarged. Increases on the weight and geometry of each component bring challenges to installations. A recent accomplished deployment on a subsea massive jumper shows the weight and length have been up to 120 tons and 90 m, respectively with sophi- sticated geometry. It is considerably difficult to install heavy and large subsea structures, especially in South China Sea where severe environmental conditions are common. In addition, deepwater deployment may alter natural frequency of the hoisting system and the altered frequency may be close to possible environmental conditions. To deal with the above two issues, traditionally, engineers need to carry out series of complicated numerical analyses which are on case basis and significantly time-consuming. Existing studies focus on the optimization on analysis techniques by conducting laboratory testing and numerical simulations. However, easy-to-use guidance on massive subsea structure installation are somewhat limited. The studies presented in this paper aim to achieve a simplified guidance which can briefly screen the cases subject to axial resonance and provide visible correlations between hoisting system integrity and key installation parameters.

关键词： subsea massive saucture sensitivity analysis DAF

Theoretical Researches on the Self-assembly System of Molecularly Imprinted Polymers Formed via Phenobarbital and Acrylamide

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Chinese Journal of Structural Chemistry 2019年第7期38卷 1069-1078页

作者： WANG Guang-Yu LIU Jun-Bo tang shan-shan CHANG Hai-Bo JIN Rui-fa College of Food Science and Engineering Jilin Agricultural University Changchun 130118China College of Resources and Environment Jilin Agricultural University Changchun 130118 China College of Life Science Jilin Agricultural University Changchun 130118 China College of Chemistry and Chemical Engineering Chifeng University Chifeng 024000 China

For preparing the phenobarbital(PHN) molecularly imprinted polymers(MIPs) with higher adsorption and selectivity properties, we used the M062 X/6-31 g(d,p) method of density functional theory to predict the various properties of PHN-MIPs. Here PHN is as the imprinted molecule and acrylamide(AM) as the functional monomer. The ethylene glycol dimethacrylate,trimethylolpropane trimethacrylate, divinyl benzene, and pentaerythritol trimethacrylate are as the cross-linking agents, respectively. The acetonitrile, chloroform, toluene, and tetrahydrofuran are used as the solvents, respectively. The configurations of the molecular imprinting self-assembly system for PHN and AM have been simulated to study their bonding sites, binding energy, amount of hydrogen bond, and interaction mechanism. The essence of imprinting interaction for PHN and AM has been revealed by the atomic in the molecule theory. Meanwhile, the analogues of PHN were used to discuss the selectivity property of the stable PHN-AM complex. The results show that the PHN interacts with AM through hydrogen bonds. When the imprinting molar ratio of PHN-AM is1:6 and the THF is as the solvent, the amount of their hydrogen bonds is the most, the binding energy is the lowest, and their configuration is the most stable. In comparison with the other cross-linking agents(EGDMA, TRIM, and DVB), the PETA is more suitable for PHN-MIPs. The selective property of PHN-MIP to PHN is excellent when PHN and DMBA exist at the same time.

关键词： PHN AM molecularly imprinted polymers computational simulation

Effect of periphyton community structure on heavy metal accumulation in mystery snail(Cipangopaludina chinensis):A case study of the Bai River,China

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Journal of Environmental Sciences 2012年第10期24卷 1723-1730页

作者： Jingguo Cui Baoqing shan Wenzhong tang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-environmental SciencesChinese Academy of ScieneesBeijing 100085China

The ratio of metal：P stoichiometry was used to identify the accumulation pathways of heavy metals （V, Cr, Co, Ni, Cu, Cd, and Pb） from periphyton to snails Cipangopaludina chinensis Gray （C. chinensis） in the Bai River watershed. The results showed that periphyton communities were mainly composed of two types of algae, filamentous green algae and unicellular diatoms. The proportion of unicellular diatoms in the periphyton community is a key factor that influences metal accumulation in C. chinensis. The V, Cr, Co, Ni, and Cd content of C. chinensis increased steadily as the corresponding metal content of periphyton increased, but Cu and Pb in the snail did not increase in the periphyton. Mechanisms of V, Cr, and Ni accumulation were found to be related to the proportion of diatoms, while Cd and Pb accumulation were dependent on the physiological characteristics of C. chinensis. The accumulation of Cu in C. chinensis was closely related to their grazing behavior. The metal：P stoichiometry revealed that Cr, Ni, and Cd can reduce the potential ecological risks associated with increased P inputs to the ecosystem. V and Co were considered to be relatively safe, regardless of the periphyton P content. Finally, Pb may not be prone to transfer to higher trophic levels, and may pose the lowest ecological risks of the studied heavy metals, but Cu can cause potential ecological risks when eutrophication has occurred.

关键词： heavy metal metal:P periphyton Chinese mystery snails Cipangopaludina chinensis

Tuning radical reactivity for selective radical/radical cross-coupling

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Science Bulletin 2018年第15期63卷 1006-1009页

作者： Shengchun Wang shan tang Aiwen Lei Institute for Advanced Studies (IAS) College of Chemistry and Molecular Sciences Wuhan University

Radical/radical cross-coupling represents a straightforward way for the construction of new chemical bonds in theory and has received more and more attention over the past several years. Until now, it is challenging to achieve the selective bond formation between two transient radicals since selective radical cross-coupling usually happens between persistent radical and transient radical. However, the number of persistent radicals is much less than that of transient radicals. These issues limit the application of radical/radical cross-coupling in the construction of new chemical bonds. To solve this, we proposed a novel strategy ‘‘tuning radical reactivity" that could tune transient radical into persistent radical. This paper will introduce the concept and recent developments of ‘‘tuning radical reactivity".

关键词： Radical/radical cross-coupling Tuning radical reactivity Oxidative cross-coupling Transient radical

Approximation of the Fractional Schrodinger Propagator on Compact Manifolds

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Acta Mathematica Sinica,English Series 2021年第10期37卷 1485-1496页

作者： Jie Cheng CHEN Da shan faN fa You ZHAO Department of Mathematics Zhejiang Normal UniversityJinhua 321000P.R.China Department of Mathematical Sciences University of Wisconsin–MilwaukeeMilwaukeeWI 53201USA Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

Let L be a second order positive,elliptic differential operator that is self-adjoint with respect to some C^(∞)density dx on a compact connected manifold *** proved that if 00.

关键词： Schrodinger propagator almost everywhere convergence compact manifolds