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Role of Residue 90 in Catalysis of Cytochrome P450 2C9

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Chemical Research in Chinese Universities 2009年第6期25卷 904-908页

作者： wang ying zhou Yi-han GUO ying-jie XU xue-lian si Da-yong zhou Hui li Ze-sheng College of life Science State Key Laboratory of Theoretical and Computational chemistry Institute of Theoretical Chemistry Jilin University Changchun 130021 P. R. China

The cytochrome P450 mutant CYP2C9.13（L90P） shows a greatly impaired catalytic activity compared with the wild-type. We constructed the mutants by substitution at residue 90 of CYP2C9, expressed in COS-7 cells, assayed their thermal stability and catalysis activity and analyzed the mutants via molecular dynamic（MD） simulation and flexible docking. Mutant L90E exhibits a significantly lower catalytic activity than the wild-type for the hydroxylation of diclofenac, lornoxicam and luciferin and its molecular dynamics simulation results indicate that the size of the entrance of substrate access was reduced significantly. An increase or minor decrease of catalytic activity was observed for mutants L90Q, L90W, L90R, L90I and L90G, and the sizes of the entrances of substrate access and the active site cavities had a little change in those mutants. The thermal stability and the potential energy of the MD simulation of these mutants showed a similar tendency as the catalysis assays did. Flexible docking results show the fluctuation of interaction energy is due to the change of electrostatic potential distribution. All the above facts show that the changes in the catalysis activity of the mutants caused by the substitution at residue 90 are due to the changes in the size of entrance, the shape and size of active site cavity, electrostatic potential distribution and thermal stability. The residue 90 of CYP2C9 has an important effect on the enzyme catalytic activity.

关键词： CYP2C9 Mutation Molecular dynamics(MD) Flexible docking Catalytic activity

STUDY OF DYE-SENsiTIZED SYSTEMS FOR PHOTOIMAGING

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Chinese Journal of Polymer Science 2001年第1期19卷 79-83页

作者： Fang Gao Chun-ying zhao Yong-yuan Yang li-dong li Insatute of Photographic chemistry Chinese Academy of Sciences Beijing 100101 China Insatute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101 China Insatute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101 China Insatute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101 China

o-Chloro-hexaarylbiimidazole (o-CI-HABI) can be sensitized efficiently by cyanine dyes, the cyclopentanone and cyclohexanone dyes, when exposed to xenon lamp (use filter cut lambda less than or equal to 400 nm). The photoreaction between the photoinitiator and the dyes was completed through an electron transfer process. Excellent results have been obtained in photoimaging studies, e.g. the resolution of the image can reach 7 mum. The influence of the content of the dyes and the heat after the exposure on the resolution of the image was investigated.

关键词： photopolymer photoimaging hexaarylbiimidazole printing plate

The Patterns of Complementary Feeding and Growth among 12 to 23 Month-Old Children in China

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Biomedical and Environmental Sciences 2021年第11期34卷 847-858页

作者： wang Shuo MEI Yue MA Zhong Hua zhao wen Hua TANG xue jun PANG xue Hong ZHANG Qian li Rui li wang Yu ying XU Tao National Center for Women and Children's Health Chinese Center for Disease Control and PreventionBeijing 100081China National Institute for Nutrition and Health Chinese Center for Disease Control and PreventionBeijing 100050China Statistical Information Center National Health Commission of People's Republic of ChinaBeijing 100044China Capital Institute of Pediatrics Beijing 100020China

Objective This study aimed to understand the characteristics of dietary patterns among children aged12 to 23 months and discusses the relationship between dietary patterns and the growth of *** Cross-sectional data were selected from the National Nutrition and Health Systematic Survey for 0 to 18 year-old children in China(n=2,449)to describe the patterns of complementary feeding and the growth of *** analysis was used to analyze complementary feeding patterns,and an analysis of variance and Bonferroni test were conducted to analyze the relationship between Z scores and complementary feeding *** Four dietary patterns were identified among the children via cluster *** Pattern 4(n=104,4.2%),children still consumed milk as their staple *** displayed the lowest grain,fruit,vegetable,egg,and flesh foods consumption,a medium frequency of breast milk consumption,and a high frequency of dairy product *** 4 had the lowest length-for-age Z scores and weight-for-age Z scores,with-0.10±1.34 and 0.24±1.00,respectively(F=7.940,Psion Although China is undergoing rapid urbanization and economic development,there is still a phenomenon of insufficient intake of protein-rich foods and dairy-based dietary patterns at the stage of complementary food introduced among children aged 12 to 23 months.

关键词： Dietary pattern Z score Growth Children aged 12 to 23 months

Combined effect of microplastic and triphenyltin:Insights from the gut-brain axis

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Environmental Science and Ecotechnology 2023年第4期16卷 156-167页

作者： si-Qi Zhang Ping li Shu-wen He Shao-ying Xing Zhi-Han Cao xue-li zhao Cuici Sun Zhi-Hua li Marine College Shandong UniversityWeihaiShandong264209China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of Sciences510301GuangzhouChina

Microplastics(MPs),an emerging group of pollutants,not only have direct toxic effects on aquatic organisms but also cause combined toxicity by absorbing other ***(TPT),one of the most widely used organotin compounds,has adverse effects on aquatic ***,little is known about the combined toxicity of MPs and TPT to aquatic *** investigate the individual and combined toxicity of MPs and TPT,we selected the common carp(Cyprinus carpio)for a 42-day exposure *** on the environmental concentrations in a heavily polluted area,the experimental concentrations of MPs and TPT were set at 0.5 mg L^(−1) and 1μg L^(−1),*** effects of MPs combined with TPT on the carp gut-brain axis were evaluated by detecting gut physiology and biochemical parameters,gut microbial 16S rRNA,and brain transcriptome *** results suggest that a single TPT caused lipid metabolism disorder and a single MP induced immunosuppression in *** MPs were combined with TPT,the involvement of TPT amplified the immunotoxic effect induced by *** this study,we also explored the gut-brain axis relationship of carp immunosuppression,providing new insights for assessing the combined toxicity of MPs and *** the same time,our study provides a theoretical basis for evaluating the coexistence risk of MPs and TPT in the aquatic environment.

关键词： Aquatic organism Combined toxicity Ecological risk Environmental concentration

Polysiloxane side-chain liquid Crystalline Polymers Prepared by Alkyne Hydrosilylation

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Chinese Journal of Polymer Science 2015年第10期33卷 1431-1441页

作者： wen zhao Bao-ping lin xue-qin Zhang ying Sun 杨洪 School of chemistry and Chemical Engineering Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research Jiangsu Optoelectronic Functional Materials and Engineering Laboratory Southeast University

We describe in this work an alkyne-hydrosilylation approach to synthesize a series of novel polysiloxane sidechain LCPs attaching end-on or side-on mesogenic side groups. Their properties are characterized by NMR, FTIR, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetty, polarized optical microscopy and small-angle X-ray scattering. These obtained alkenylsilane linked novel LCPs exhibit higher glass transition temperatures and clearing points, and especially display the tendency of forming smectic phases, in strong contrast with the nematic phases of their comparative conventional alkylsilane linked analogues, which manifests more rigid features of the alkenylsilane linkages and their significant influence on the mesomorphic properties.

关键词： liquid crystalline polymer Polysiloxane Alkyne hydrosilylation

Preparation of active coke combining coal with biomass and its denitrification performance

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Journal of Iron and Steel Research International 2021年第10期28卷 1203-1211页

作者： Xiao-hu zhou Sheng-fu Zhang Yu-yang Wei Farooq Sher Yang li wen-zhou Yu liang-ying wen College of Materials Science and Engineering Chongqing UniversityChongqing400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and Advanced Materials Chongqing UniversityChongqing400044China School of Mechanical Aerospace and Automotive EngineeringFaculty of EngineeringEnvironment and ComputingCoventry UniversityCoventryCV15FBUK

To improve the selective catalytic reduction of NO with NH3 over active coke(AC),coal–biomass ACs were prepared from the mixture of poplar and 1/3 coking coal for increasing the active *** resultant ACs were characterized by N2 adsorption and X-ray photoelectron ***,the denitrification performance was tested at laboratory *** addition,density functional theory was used to analyze active sites on the surface of *** result revealed that,with an increase in poplar content,the decrease in micropores volume appeared in the reduction of denitrification ***,C−O group including hydroxyl and ether increased with the increase in poplar content,which was found to be most likely responsible for the promoted catalytic activity of AC toward NO reduction mainly because of enhancing NH3 *** comprehensive effect of two factors made the denitrification ability of AC increased first and then decreased.

关键词： Active coke Denitrification Pore structure Functional group Density functional theory

Synthesis and Characterization of PEG Polymer Brushes via Cyclopolymerization of 1,2,3-Triazole Tethered Diacrylates

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Xiao-ying zhao He-wen liu Key Laboratory of Soft Matter chemistry Chinese Academy of Sciences Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 China

Poly(ethylene glycol) (PEG) macromolecular brushes were synthesized directly via reversible addition-fragmentation chain transfer polymerization cyclopolymerization of diacrylate monomers bearing PEG functional groups through the formation of 11-member rings. The diacrylate monomers bearing PEG functional groups are the 1,2,3-triazole-tethered diacrylate macromolecular monomers with di erent PEG lengths synthesized via the so-called “click” chemistry. The bulky hindrance of PEG chains affected the polymerization behavior of the diacrylate macromolecular monomers, and the diacrylate monomers showed strong tendency to cyclopolymerization rather than crosslinking. NMR analysis and gel permeation chromatography profiles proved the high efficiency of cyclopolymerization without side reactions. The aqueous solutions of the obtained PEG macromolecular brushes were fluorescent under UV excitation. The fluorescence depended dramatically on the concentration of brush-like polymers due to the aggregation of cyclopolymer in water, and could be quenched by the addition of DNA.

关键词： Cyclopolymerization Macromolecular brush Fluorescence quenching DNA

Topological analysis of plasma flow control on corner separation in a highly loaded compressor cascade

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Acta Mechanica sinica 2012年第5期28卷 1277-1286页

作者： Xiao-Hu zhao Yun Wu ying-Hong li xue-De wang Qin zhao Science and Technology on Plasma Dynamics Laboratory Air Force Engineering University

In this paper, flow behavior and topology structure in a highly loaded compressor cascade with and without plasma aerodynamic actuation （PAA） are investigated. Streamline pattern, total pressure loss coefficient, outlet flow angle and topological analysis are considered to study the effect and mechanism of the plasma flow control on corner separation. Results presented include the boundary layer flow behavior, effects of three types of PAA on separated flows and performance parameters, topology structures and sequences of singular points with and without PAA. Two separation lines, reversed flow and backflow exist on the suction surface. The cross flow on the endwall is an important element for the comer separation. PAA can reduce the undertuming and overturning as well as the total pressure loss, leading to an overall increase of flow turning and enhancement of aerodynamic performance. PAA can change the topology structure, sequences of singular points and their corresponding separation lines. Types II and III PAA are much more efficient in controlling comer separation and enhancing aerodynamic performances than type I.

关键词： Plasma aerodynamic actuation - Compressor Cascade Topology structure Corner separation

Numerical investigation of the coupled aero-hydrodynamic performances of a semi-submersible floating offshore wind turbine with inclined columns

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Journal of Hydrodynamics 2024年第2期36卷 316-330页

作者： ying-jie xue Xiao-long Yang Wei-wen zhao De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Offshore Oil Engineering Co.Ltd. Tianjin300461China

Numerical investigations of floating platforms with different outer column inclined angles under two operating conditions of regular wave and irregular wave are presented in this paper.A coupled aero-hydrodynamic computational fluid dynamics in-house solver FOWT-UALM-SJTU is applied for the ***,the validation for wave and wind generation are conducted to determine mesh distribution *** on these,the hydrodynamic motion response,aerodynamic performance and wake flow are analyzed to explore the impact of inclined *** spectral analysis on the motion response under wave action,discuss the aerodynamic attack angle and inflow wind velocity along the blade spanwise direction in detail,reveal different trends in wake development and *** results show that for the regular wave condition with the increase of inclined angles,the equilibrium position of surge motion is constantly rising,while pitch is *** maximum root mean square(rms)value occurs at angle=30°,compared with the original OC4 FOWT,the rms in power and thrust increase 0.35%,0.71%.And there are two low regions of attack angle and high regions of axial inflow velocity,corresponding to aerodynamic *** spectral analysis indicates that the natural frequency of pitch motion will increase with inclined ***,from the middle to far region of wake flow,the velocity recovery of FOWT with inclined angle will become faster,which is beneficial for downstream turbines to enhance more wind energy.

关键词： Floating offshore wind turbine numerical simulation aero-hydrodynamic coupled analysis floating platform with inclinedcolumns wake flow recovery