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Acta Metallurgica Sinica(English Letters) 2022年第5期35卷 812-824页

作者： Sijie Qin Xiongcheng Xu y.njin Lu Liu Li tingting Huang Jinxin Lin Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China University of the Chinese Academy of Sciences Beijing100049China College of Chemistry Fuzhou UniversityFuzhou350108China Research Center of Oral Tissue Engineering School and Hospital of StomatologyFujian Medical UniversityFuzhou350001China

In this study,we fabricated poly(3-hydroxybutyrate-3-hydroxyvalerate)(PHBV)coatings doped with Gd^(3+)(1,5,and 10×10^(−4) mol/L)on Ti6Al4V alloy for the first time to promote soft tissue sealing around dental *** corrosion resistance of Gd^(3+)-modified PHBV-coated Ti6Al4V was studied by electrochemical and immersion tests,respectively,whereas CCK-8 and RT-PCR evaluated the biocompatibility to human gingival fibroblasts(HGFs)and human umbilical vein endothelial cells(HUVECs).It was found that the Gd^(3+)-modified PHBV coating could enhance the corrosion resistance of *** vitro cell tests showed that PHBV coatings with and without Gd^(3+) addition could promote adhesion and proliferation of HGFs and HUVECs,showing a Gd^(3+) content-dependent ***,it was found that the PDA-PHBV@1Gd showed the best proliferation to HGFs by up-regulating gene expressions of VInCULIn,ITGB1,and ITGA3,whereas the best response to HUVECs with the highest gene expression of enOS and HIF-1αgenes was found in the PDA-PHBV@5Gd-coated group.

关键词： Soft tissue sealing Poly(3-hydroxybutyrate-3-hydroxyvalerate)(PHBV) Gd^(3+) Corrosion resistance Human gingival fibroblasts

Molten salt electrochemical modulation of ni/Co nanoparticles onto n-doped carbon for oxygen reduction

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Journal of Energy Chemistry 2022年第11期31卷 212-217,I0007页

作者： Xinxin Liang Jialin Chen Biao Hong tingting Wan Wei Weng Wei Xiao College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072HubeiChina Zijin School of Geology and Mining Fujian Key Laboratory of Green Extraction and High-value Utilization of Energy MetalsFuzhou UniversityFuzhou 350108FujianChina Queen Marry University of London Engineering School Northwestern Polytechnical UniversityXi’an 710129ShaanxiChina

Activation of oxygen over non-precious materials has been an imperative task to develop efficient electrochemical energy storage and conversion such as fuel cells and metal-air ***,a molten salt electrochemical modulation of metal-nitrogen-carbon based compounds(M–n–C)is *** electrochemical treatment of polydopamine-coated niCo_(2)O_(4)(niCo_(2)O_(4)@PDA)in molten Li_(2)CO_(3)-na_(2)CO_(3)-K_(2)CO_(3)at 500℃,ni/Co bimetal-nitrogen-carbon catalyst(denoted as ni/Co@nC)consisting of ni-Co nanoparticles anchoring on porous nitrogen-doped carbon is constructed and evaluated as electrocatalysts towards the oxygen reduction reaction(ORR).Experimental and calculation results confirm that alloy.ng of ni-Co and nitrogen doping to carbon enhances the rate-determining transformation of*OH intermediate during *** ni/Co@nC hence shows an ORR activity comparable with the commercial Pt/C.

关键词： Oxygen reduction Metal-nitrogen-carbon Electrochemistry Molten salt Bimetal modulation

Electrify.ng the future:the advances and opportunities of electrocatalytic carbon dioxide reduction in acid

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Science China Chemistry 2023年第12期66卷 3426-3442页

作者： Runhao Zhang Haoyuan Wang yuan Ji Qiu Jiang tingting Zheng Chuan Xia y.ngtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Hefei national Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

Transforming carbon dioxide(CO_(2))into products using renewable electricity is a crucial and captivating quest for a green and circular *** with commonly used alkali electrolytes,acidic media for electrocatalytic CO_(2) reduction(CO_(2)RR)boasts several advantages,such as high carbon utilization efficiency,high overall energy utilization rate,and low carbonate formation,making it a compelling choice for industrial ***,the acidic CO_(2)RR also struggles with formidable hurdles,encompassing the fierce competition with the hydrogen evolution reaction,the low CO_(2) solubility and availability,and the suboptimal performance of *** review provides a comprehensive overview of the CO_(2)RR in acidic *** elucidating the underly.ng regulatory mechanism,we gain valuable insights into the fundamental principles governing the acidic CO_(2)***,we examine cutting-edge strategies aimed at optimizing its performance and the roles of reactor engineering,especially membrane electrode assembly reactors,in facilitating scalable and carbon efficient ***,we present a forward-looking perspective,highlighting the promising prospects of acidic CO_(2)RR research in ushering us towards a carbon-neutral society.

关键词： electrocatalytic CO_(2)reduction acidic electrolyte microenvironment alkali metal cations electrolysers

Experiment and modeling of coke formation and catalyst deactivation in n-heptane catalytic cracking over HZSM-5 zeolites

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Chinese Journal of Chemical Engineering 2023年第3期55卷 165-172页

作者： Zhenzhou Ma Xu Hou Bochong Chen Liu Zhao Enxian yuan tingting Cui School of Chemical Engineering Changchun University of TechnologyChangchun 130012China Advanced Institute of Materials Science Changchun University of TechnologyChangchun 130012China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009China Department of Chemistry Tsinghua UniversityBeijing 100084China

Since paraffins catalytic cracking was of significant importance to light olefins and aromatics production,this work was intended to gain insights into the feature and model of coke formation and catalyst deactivation in n-heptane catalytic cracking over HZSM-5 zeolites. 18 tests of n-heptane catalytic cracking were designed and carried out over HZSM-5 zeolites in a wide range of operating conditions. A particular attention was paid to the measurement of the conversion, product distribution, coke content, and the porosity and acidity of the fresh and spent HZSM-5 zeolites. It was found that alkene and aromatic promoted coke formation, and it reduced the pore volume and acid site of HZSM-5 zeolites, tailoring its performance in n-heptane catalytic cracking. The specific relationship between HZSM-5 zeolites, n-heptane conversion, product distribution and coke formation was quantitively characterized by the exponential and linear function. Based on the reaction network, the coupled scheme of coke formation and catalyst deactivation were specified for n-heptane catalytic cracking. The dual-model was proposed for the process simulation of n-heptane catalytic cracking over HZSM-5 zeolites. It predicted not only the conversion and product distribution but also coke content with the acceptable errors.

关键词： n-Heptane HZSM-5 Catalytic cracking Coke Deactivation Dual-model

A Multiple Model Approach to Modeling Based on LPF Algorithm

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Journal of Systems Engineering and Electronics 2001年第3期12卷 64-70页

作者： Li, n. Li, S. Xi, y. Institute of Automation Shanghai Jiaotong University Shanghai 200030 China

Input-output data fitting methods are often used for unknown-structure nonlinear system modeling. Based on model-on-demand tactics, a multiple model approach to modeling for nonlinear systems is presented. The basic idea is to find out, from vast historical system input-output data sets, some data sets matching with the current working point, then to develop a local model using Local Polynomial Fitting (LPF) algorithm. With the change of working points, multiple local models are built, which realize the exact modeling for the global system. By comparing to other methods, the simulation results show good performance for its simple, effective and reliable estimation.

关键词： Algorithms Computer simulation Data structures Input output programs Mathematical models Parameter estimation Polynomials

Quality assessment and hydrogeochemical characteristics of groundwater in Agastheeswaram taluk, Kanyakumari district, Tamil nadu, India

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Chinese Journal Of Geochemistry 2014年第3期33卷 221-235页

作者： Srinivas y Hudson Oliver D Stanley Raj A Chandrasekar n Centre for GeoTechnology Manonmaniam Sundaranar University Vel Tech Dr. RR & Dr. SR Technical University Avadi Chennai

The present study investigates the hydrogeochemical characteristics of groundwater quality in Agastheeswaram taluk of Kanyakumari district, Tamil nadu, India. A total of 69 groundwater samples were collected during pre- and post-monsoon periods of 2011–2012. The groundwater quality assessment has been carried out by evaluating the physicochemical parameters such as pH, EC, TDS, HCO3-, Cl-, SO42-, Ca2+, Mg2+, na+ and K+ for both the seasons. Based on these parameters, groundwater has been assessed in favor of its suitability for drinking and irrigation purpose. Dominant cations for both the seasons are in the order of na+ > Ca2+ > Mg2+ > K+ while the dominant anions for post monsoon and pre monsoon have the trends of Cl- > HCO3- > SO42- and HCO3- > Cl- > SO42-, respectively. Analytical results observed from various indices reveal that the groundwater quality is fairly good in some places. Analytical results of few samples show that they are severely polluted and incidentally found to be near the coasts, estuaries and salt pans in the study area. The Gibbs plot indicates that the majority of groundwater samples fall in rock dominant region, which indicates rock water interaction in the study area. The United States salinity(USSL) diagram shows that the groundwater is free from sodium hazards but the salinity hazard varies from low to very high throughout the study area. This reveals that the groundwater is moderately suitable for agricultural activities. The observed chemical variations in pre-monsoon and post-monsoon seasons may be the effect to rock-water interactions, ion-exchange reactions, and runoff of fertilizers from the surrounding agricultural lands.

关键词：地下水质量评价地下水水质水文特性马里印度水岩相互作用物理化学参数研究区域

STUDy On THE THERMODynAMICS OF CuO/Al In SITU Al_2O_3 REInFORCED Al MATRIX COMPOSITES

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 732-740页

作者： y.Ma y.Hao S.Z.Kou X.n.Lu StateKeyLab.ofAdvancednonferrousMaterials LanzhouUniversityofTechnologyLanzhou730050China

Based on the experiment and the thermodynamics analysis for CuO/Al system, it is founded that the compounding reaction of CuO/Al under low temperature is available. The general equation of adiabatic temperature of the system is set up, and the influence of resultant concentration and temperature on adiabatic temperature is theoretically analyzed. The values of heat effect of CuO/Al system under different temperature are also caculated.

关键词： composites in situ thermodynamics CuO Al exothermic dispersion

The engagement of histone lysine methyltransferases with nucleosomes: structural basis, regulatory mechanisms, and therapeutic implications

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Protein & Cell 2023年第3期14卷 165-179页

作者： y.njing Li Kexue Gei tingting Li Run Cai y.ng Chen State Key Laboratory of Molecular Biology National Center for Protein Science ShanghaiShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academyof Sciences320 Yue Yang RoadShanghai 200031China State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai Collaborative Innovation Center for Biomanufacturing(SCICB)Meilong Road 130Shanghai 200237China

Histone lysine methyltransferases(HKMTs)deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene *** structures and functions of HKMTs have been extensively investigated in recent decades,significantly advancing our understanding of the dynamic regulation of histone ***,we review the recent progress in structural studies of representative HKMTs in complex with nucleosomes(H3K4,H3K27,H3K36,H3K79,and H4K20 methyltransferases),with emphasis on the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these *** structural studies inform HKMTs'roles in tumorigenesis and provide the foundations for developing new therapeutic approachestargetingHKMTs incancers.

关键词： nucleosome cryo-EM structures histone methyltransferases epigenetics histone methylation tumorigenesis

Phytotoxicity of cadmium on protein, proline and antioxidant enzyme activities in growing Arachis hypogaea L. seedlings

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Journal of Environmental Sciences 2008年第2期20卷 199-206页

作者： n Dinakar P C nagajyothi S Suresh y Udaykiran T Damodharam Department of Environmental Sciences Sri Venkateswara UniversityTirupatiAndhra Pradesh-517 502India.

Phytotoxicity of cadmium on growing Arachis hypogaea L. seedlings was studied. Seeds were exposed to 25, 50, and 100 μmol/L CdCl2 concentrations, for a period of 10, 15, 20 and 25 d. The extent of damage to chlorophyll, protein, proline, nitrate and nitrite reductase, antioxidant enzyme activity in leaves and roots were evaluated after 10 d of cadmium stress. The higher concentration of cadmium （100 μmol/L） resulted （leaves and roots） total chlorophyll 91.01%, protein 79.51%, 83.61%, nitrate reductase 79.39%, 80.72% and nitrite reductase 77.07%, 75.88% activity decreased with increase in cadmium concentrations and exposure periods. Cadmium caused significant changes in the activity of antioxidative enzymes. Contrastingly Cd treated plant tissues showed an increase in proline 159.87%, 239.6%, gluthion reductase （GR） 337.72%, 306.14%, superoxide disumutase （SOD） 688.56%, 381.72%, ascorbate peroxidase （APX） 226.47%, 252.14%, peroxidase （POD） 72.19%, 60.29% and catalase （CAT） 228.96%, 214.74% as compared to control. Cadmium stress caused a significant increase in the rate of SOD activity in leaves and roots of plant species. Results show the crop A. hypogaea is highly sensitive even at very low cadmium concentrations.

关键词： toxicological effects cadmium protein proline antioxidant enzymes

Adsorptive interaction between typical VOCs and various topological zeolites:Mixture effect and mechanism

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Journal of Environmental Sciences 2024年第2期136卷 626-636页

作者： Bo yu Hua Deng yuqin Lu tingting Pan Wenpo Shan Hong He Center for Excellence in Regional Atmospheric Environment and Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Adsorption is one of the most feasible and effective methods to alleviate the volatile organic compounds(VOCs)***,the mixture effect and mechanism for competitive adsorption of VOCs on zeolites are barely *** this study,toluene,acetone,and ethyl acetate as prevalent VOCs species were removed by four potential zeolites(13X,USy,Beta,ZSM-5)in both single-and multi-component *** structure-property relationship between adsorbate-adsorbent pairs was revealed by X-ray diffraction,scanning electron microscopy,energy dispersive spectrometer,X-ray fluorescence,n_(2) adsorption and density function theory *** molecular polarity and volatility of VOCs species played key roles in adsorption and the dynamic uptakes were generally listed as follows:ethyl acetate>toluene>*** for the above VOCs mixtures,13X zeolite selectively adsorbed oxygenated VOCs rather than *** contrast,USy exhibited a preference to trap *** acetate could be readily enriched by ZSM-5 and Beta *** possible explanations and implications are discussed based on the subtle change in electron *** results obtained are vital for understanding the mixture effect of VOCs adsorption and may guide the selection of proper adsorbent for real applications.

关键词： Adsorption Zeolites VOCs Mixture effect DFT