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Effect of non-cyanide zincation process parameters on the microstructure of the zincation layer on A356 alloys

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Rare Metals 2007年第S1期26卷 313-317页

作者： ZHU Zhaojun1),and huang xiaomei2.1) School of materials {2. and Engineering,harbin Institute of Techmology,harbin 150001,china 2. college of materials {2. and chemical Engineering,harbin Engineering university,harbin 150001,china harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China harbin Engn Univ Coll Mat Sci & Chem Engn Harbin 150001 Peoples R China

The effects of non-cyanide zincation process parameters on the microstructure of the zincation layer on A356 alloy were investigated by scanning electronic *** the increasing of zincation time,the zinc grain size and the number density increase gradually,and the zinc grains adhere each *** zinc grain obtained in the double-dipping process is finer,compacter and more homogeneous than that obtained in the single-dipping *** the increasing of the zincation temperature,the morphology of zinc grains changes from spherical shape to flake-like ***,higher zincation temperature results in the flaking off of the zincation layer from the *** optimized zincation temperature is 2.-30 ℃.The quality of the zincation layer obtained in a low concentration,non-cyanide and multi-element zincation solutions is much better than these obtained in conventional high concentration zincation solution,dilute zincation solutions or a dilute zincation solution containing *** addition,the matrix alloy and the pre-treatment also have significant influence on the morphology of the zincation layer.

关键词： non-cyanide zincation solution zincation time zincation temperature morphology

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. zhang Jiao qiang 3 (1. Department of Chemistry,Northwest university, Xi′an 710065, {2. 2. Department of Chemistry and chemical Engineering, Baoji college of Arts and science, Baoji 72.007, {2. 3. Department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Modulating the electrode–electrolyte interface enables switchable selectivity in electrocatalytic furfural reduction

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science china Chemistry 2024年第10期67卷 3193-3194页

作者： Jingfang zhang Yi huang Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education School of Chemical Engineering&PharmacyWuhan Institute of TechnologyWuhan 430205China college of Chemistry Central China Normal UniversityWuhan 430079China

Furfural(FF),an important bio-based platform molecule,can be valorized to high-value-added chemicals(e.g.,furfuryl alcohol(FA)or 2.methylfuran(MF))through catalytic hydrogenation[1].The traditional thermocatalytic transformation of FF always requires high-temperature and highpressure conditions[2..Accordingly,electrocatalytic hydrogenation is emerging as a promising approach for the selective reduction of FF to FA or MF under environmentally friendly and benign conditions.

关键词： hydrogenation electrolyte selectivity

Effect of samarium doping on the activity and sulfur resistance of Ce/MnFeO_(x) catalyst for low-temperature selective catalytic reduction of NO_(x) by ammonia

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Chinese Journal of chemical Engineering 2024年第7期71卷 272-282页

作者： Qiyao zhang Shuangshuang zhang Xu Hu Yongmin huang Key Laboratory of Specially Functional Polymeric materials and Related Technology School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

The self-made MnFeO_(x) catalysts doped with cerium and samarium were prepared by impregnation method for low-temperature selective catalytic reduction(SCR)by *** this work,the surface properties of the series of MnFe-based catalysts were *** results indicate Sm-modified catalyst have superior low-temperature SCR activity;NO_(x) conversion maintained at nearby to 100%at 90℃ to 2.0℃.In addition,The N_(2. selectivity of Sm doping remains above 80%in the range of 60℃ to 150℃.In SO_(2. poisoning test,the NO_(x) conversion can be remained>90%after 10 h of *** XPS,NH_(3)-TPD and H_(2.-TPR results show the catalyst with Sm doping enhances the acid sites and oxidation catalytic sites of mixed oxides serves for improving oxygen vacancies and transfer *** situ diffuse reflaxions infrared Fourier transformations spectroscopy(DRIFTS)results show that NO_(x) is more easily adsorbed on the surface after Sm doping,which provided favorable conditions for the NH_(3)-SCR reaction to *** reaction at the catalyst surface will follow the L-H reaction mechanism by transient reaction test.

关键词： SCR Sm doping Catalyst Sulfur resistance In situ DRIFTS Selectivity

Dilute Aqueous-Aprotic Electrolyte Towards Robust Zn-Ion Hybrid Supercapacitor with High Operation Voltage and Long Lifespan

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Nano-Micro Letters 2024年第9期16卷 1-12页

作者： Shuilin Wu Yibing Yang Mingzi Sun Tian zhang Shaozhuan huang Daohong zhang Bolong huang Pengfei Wang Wenjun zhang Key Laboratory of Catalysis and Energy materials Chemistry of Ministry of Education&Hubei Key Laboratory of Catalysis and materials {2. South-Central Minzu UniversityWuhan 430074People’s Republic of China Department of materials science and Engineering and Center of Super‑Diamond and Advanced FilmsCity University of Hong Kong83 Tat Chee AvenueKowloon TongHong Kong SARPeople’s Republic of China Department of Applied Biology and chemical Technology The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Key Laboratory of Photochemical Conversion and Optoelectronic materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingPeople’s Republic of China

With the merits of the high energy density of batteries and power density of supercapacitors,the aqueous Zn-ion hybrid supercapacitors emerge as a promising candidate for applications where both rapid energy delivery and moderate energy storage are ***,the narrow electrochemical window of aqueous electrolytes induces severe side reactions on the Zn metal anode and shortens its *** also limits the operation voltage and energy density of the Zn-ion hybrid ***'water in salt'electrolytes can effectively broaden their electrochemical windows,but this is at the expense of high cost,low ionic conductivity,and narrow temperature compatibility,compromising the electrochemical performance of the Zn-ion hybrid ***,designing a new electrolyte to balance these factors towards high-performance Zn-ion hybrid supercapacitors is urgent and *** developed a dilute water/acetonitrile electrolyte(0.5 m Zn(CF_(3)SO_(3))_(2.+1 m LiTFSI-H_(2.O/AN)for Zn-ion hybrid supercapacitors,which simultaneously exhibited expanded electrochemical window,decent ionic conductivity,and broad temperature *** this electrolyte,the hydration shells and hydrogen bonds are significantly modulated by the acetonitrile and *** a result,a Zn-ion hybrid supercapacitor with such an electrolyte demonstrates a high operating voltage up to 2.2.V and long lifespan beyond 12.,000 cycles.

关键词： Zn-ion supercapacitors Zn metal anode Electrolyte engineering Hydrogen bonds Solvation structures

Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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science china Chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2. zhang GuoLi2. huang KeLong2. LI Yuanjian3 & YI JianMin1,2.1 Department of Chemistry and {2. Engineering, Hunan Institute of science and Technology, Yueyang 414000, china 2.college of Chemistry and {2. Engineering, Central South university, Changsha 410083, china 3 college of Pharmaceutical science, Central South university, Changsha 410078, china Department of Chemistry and chemical Engineering Hunan Institute of Science and TechnologyYueyang 414000China college of Chemistry and chemical Engineering Central South UniversityChangsha 410083China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2.dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 2..6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

Surface Films Formed on SnO_2.Anode in Lithium Secondary Batteries by FTIR Spectroscopy

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Journal of Wuhan university of Technology(materials {2.) 2008年第5期23卷 662-665页

作者：黄峰 Hubei Refractories and High-temperature Ceramics Key Laboratory Wuhan University of Science and Technology

The chemical composition of the passivating layer formed on nano SnO2.anodes in 1 M LiClO4＋（ethylene carbonate）EC ＋（dimethyl carbonate）DMC at different charge/discharge states in lithium secondary batteries was studied using extra reflectance FTIR spectra. Results show that solvent decomposition reaction that generally occurs on the surface of carbon and alkali metal electrodes also takes place on nano-SnO2.anode, and the major constituent of the passivating layer is Li2.O3 and ROCO2.i. Formation of the passivating layer would certainly lead to the irreversible capacity loss.

关键词： nano-SnO2.anode lithium rechargeable batteries FTIR passivating layer

A multi-kernel-shell indium selenide@carbon nanosphere enabling high-performance lithium-ion batteries

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Journal of Energy Chemistry 2024年第9期96卷 698-708页

作者： Sihao Wang Zhuoming Jia Ying Zhao Yanhong Li Xianglong Kong Yongde Yan Fei He milin zhang Linzhi Wu Piaoping Yang Wenwu Li Meilin Liu Zhiliang Liu college of Material sciences and {2. Engineering Harbin Engineering UniversityHarbin 150001HeilongjiangChina School of materials science&Engineering Georgia Institute of TechnologyAtlantaGA 30332USA School of chemical Engineering Sungkyunkwan University 2066Seobu-roJangan-guSuwon 440-746Republic of Korea college of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001HeilongjiangChina

Indium selenide has garnered significant attention for high volumetric capacities,but is currently plagued by the sluggish charge transfer kinetics,severe volume effect,and rapid capacity degradation that hinder their practical ***,we design,synthesize,and characterize a multi-kernel-shell structure comprised of indium selenide encapsulated within carbon nanospheres(referred to as m-K-S In_(2.Se_(3)@C)through an integrated approach involving a hydrothermal method followed by a gaseous selenization ***,experimental measurements and density functional theory calculations confirm that the m-K-S In_(2.Se_(3)@C not only improve the adsorption capability for Li-ions but also lower the energy barrier for Li-ions *** from numerous contact points,shorter diffusion distances and an improved volume buffering effect,the m-K-S In_(2.Se_(3)@C achieves an 800 mA h g^(−1)capacity over 1000 loops at 1000 mA g^(−1),a 52. mA h g^(−1)capacity at 5000 mA g^(−1)and an energy density of 2.0 Wh kg^(−1)when coupled with LiFePO4,surpassing most related anodes reported ***,the m-K-S structure with unique nano-micro structure offers a new approach to the design of advanced anodes for LIBs.

关键词： Multi-kernel-shell structure In_(2.Se_(3) Anode Li-ion batteries

Mechanical parameter evolutions and deterioration constitutive model for ductile-brittle failure of surrounding rock in high-stress underground engineering

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Underground Space 2024年第2期15卷 131-152页

作者： Zhi Zheng Ronghua Li Qiang zhang Xiaohua huang Wei Wang Shuling huang State Key Laboratory of Featured Metal materials and Life-cycle Safety for Composite Structures Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 110819China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Yangtze River Scientific Research InstituteWuhan 430010China

The deep surrounding rock is usually in the true triaxial stress state,and previous constitutive models based on the understanding of uniaxial and conventional triaxial test results have difficulty characterizing the degradation and fracture process of rock ductile–brittle failure under true triaxial stress ***,this study conducted a series of true triaxial tests to obtain the understanding of the ductile–brittle behaviour of rock,and then combined the test results and the Mogi–Coulomb strength criterion,and proposed calculation methods for the elastic modulus E,cohesion c and internal friction angle u and the evolution functions of E,c and u of rock under true triaxial *** the decreasing of the minimum principal stress r3 or increasing of the intermediate principal stress r2.the marble post-peak stress drop rate gradually increases,the ductility gradually weakens,and the brittleness significantly *** calculation method and evolution function of rock E,c and u under true triaxial stress were proposed.E decreased at first and then tended to remain stable with the increasing of equivalent plastic strain increment dep.c and u slowly increased at first and then rapidly *** a method of parameter degradation rate to realize post-peak stress drop rate to reflect the ductile–brittle characteristics,a new three-dimensional ductile–brittle deterioration mechanical model(3DBDM)was *** proposed model can accurately characterize the influence of r2.and r3 on mechanical parameters,the ductile–brittle behaviour of rock under true triaxial stresses,and the asymmetric failure characteristics of surrounding rock after excavation of deep underground *** proposed model can be reduced to elastic–perfectly plastic,elastic–brittle,cohesion weakening friction strengthening(CWFS),Mohr–Coulomb,and Drucker–Prager models.

关键词： True triaxial stress Post-peak characteristics 3D deterioration model Elastic modulus evolution Cohesion and friction angle evolution