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高活性高选择性苯部分加氢制环己烯催化剂的研究

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燃料化学学报 2001年第z1期29卷 126-129页

作者：刘寿长王海荣韩民乐罗鸽杨邦举谢云龙郑州大学工业催化研究所河南郑州450052

用化学还原法制得了高活性高选择性Ru Zn B/ZrO2 苯部分加氢催化剂体系。催化剂制备中活性组分前驱体RuCl3 宜在ZrO2 上吸附后再还原。催化剂的活性指数γ4 0 和SHE分别为 15 4 7%和 85 5 % ,均高于进口催化剂水平γ4 0 和SHE分别为 10... 详细信息

用化学还原法制得了高活性高选择性Ru Zn B/ZrO2 苯部分加氢催化剂体系。催化剂制备中活性组分前驱体RuCl3 宜在ZrO2 上吸附后再还原。催化剂的活性指数γ4 0 和SHE分别为 15 4 7%和 85 5 % ,均高于进口催化剂水平γ4 0 和SHE分别为 10 0 %～ 12 0 %和 75 %～ 80 % ,具有很好的应用前景。催化剂中Ru Zn B为三元非晶合金 ,B以元素态和NaBO3·3H2 O化合物存在。随反应温度提高 ,合金分解 ,Ru晶化。反应浆液中加入ZnSO4 ·7H2 O可有效降低活性。

关键词：苯部分加氢环己烯钌催化剂化学还原法

Reverse Transformation in[110]-Oriented Face-Centered-Cubic Single Crystals Studied by Atomic Simulations

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Acta Metallurgica Sinica(English letters) 2022年第10期35卷 1631-1640页

作者： hai-Feng Zhang hai-le Yan Feng Fang Nan Jia Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang110819China State Key Lab Rolling&Automat Northeastern UniversityShenyang110819China

Bidirectional transformations,which are achieved by triggering both dynamic forward transformation from the face-centered-cubic(fcc)austenite to the hexagonal-close-packed(hcp)martensite and the reverse transformation from martensite to austenite during cold deformation,have been previously reported in FeMnCoCr-based high-entropy alloys(HEAs).This leads to the permanent refinement of microstructure and hence enhances the work-hardening capacity of *** order to reveal the microscopic mechanism of the reverse transformation in HEAs under deformation,the effect of the sample aspect ratio,i.e.,Z/X,on the evolution of deformation systems in the equi-atomic FeMnCoCrNi alloy with[110]orientation during uniaxial tensile loading along the Z direction is investigated by atomic simulations in this *** the aspect ratio is 0.5,the reverse transformation is more significant compared with other models,while a good plasticity can still be *** then compare the micromechanical behavior of three fcc single crystals,i.e.,FeMnCoCrNi,FeCuCoCrNi,and pure *** results show that the stacking fault energy plays a major role in the activation of different deformation mechanisms;however,the lattice distortion in the HEA does not significantly affect the activation of deformation ***,for all materials dislocation slip leads to the softening,while strain hardening is attributed to the initiation of multiple deformation *** Shockley partials slip leads to bidirectional phase transition,twinning and detwinning in the three ***,the reverse transformation can occur in all metallic materials where the fcc to hcp phase transformation is the dominant deformation *** findings contribute to an in-depth understanding of the deformation mechanism in fcc-structured materials under severe plastic deformation and provide theoretical guidance for the design of alloys with superior strength–plasticity combinations.

关键词： Face-centered-cubic materials Atomic simulation Plastic deformation Reverse transformation

Orientation-Dependent Mechanical Responses and Plastic Deformation Mechanisms of FeMnCoCrNi High-entropy Alloy:A Molecular Dynamics Study

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Acta Metallurgica Sinica(English letters) 2021年第11期34卷 1511-1526页

作者： hai-Feng Zhang hai-le Yan Feng Fang Nan Jia Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China State Key Lab Rolling&Automat Northeastern UniversityShenyang 110819China

Mechanical properties of high-entropy alloys(HEAs)with the face-centered cubic(fcc)structure strongly depend on their initial grain ***,the orientation-dependent mechanical responses and the underlying plastic fl ow mechanisms of such alloys are not yet well ***,deformation of the equiatomic FeMnCoCrNi HEA with various initial orientations under uniaxial tensile testing has been studied by using atomistic simulations,showing the results consistent with the recent experiments on fcc *** quantitative analysis of the activated deformation modes shows that the initiation of stacking faults is the main plastic deformation mechanism for the crystals initially oriented with[001],[111],and[112],and the total dislocation densities in these crystals are higher than that with the[110]and[123]*** faults,twinning,and hcp-martensitic transformation jointly promote the plastic deformation of the[110]orientation,and twinning in this crystal is more significant than that with other *** in the crystal oriented with[123]is dominated by the hcp-martensite *** of the mechanical behaviors in the FeMnCoCrNi alloy and the conventional materials,*** and Fe50Ni50,has shown that dislocation slip tends to be activated more readily in the *** is attributed to the larger lattice distortion in the HEA than the low-entropy materials,leading to the lower critical stress for dislocation nucleation and elastic–plastic transition in the *** addition,the FeMnCoCrNi HEA with the larger lattice distortion leads to an enhanced capacity of storing ***,for the[001]-oriented HEA in which dislocation slip and stacking fault are the dominant deformation mechanisms,the limited deformation modes activated are insu fficient to improve the work hardening ability of the material.

关键词： High-entropy alloy Molecular dynamics study Mechanical response Plastic deformation mechanism

In situ polymerization of 1,3-dioxolane infiltrating 3D garnet framework with high ionic conductivity and excellent interfacial stability for integrated solid-state Li metal battery

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Rare Metals 2022年第11期41卷 3694-3705页

作者： Lin-Hui Chen Ze-Ya Huang Shi-le Chen rong-Ao Tong hai-Long Wang Gang Shao Chang-An Wang State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing210016China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001China

The polymer-ceramic composite electrolyte is considered as one of promising electrolytes for solid-state ***,in previous research,ceramic particles are usually dispersed in polymer matrix and could not form continuous Li+conductive *** agglomeration of ceramic particles could also lead to low ionic conductivity and poor interfacial electrode/electrolyte *** this paper,self-supported porous Li_(6.4)La_(3) Zr_(1.4)Ta_(0.6)O_(12)(LLZTO) electrolyte is synthesized by gelcasting process,which possesses three-dimensional(3D) interconnected pore channels and relatively high *** 1,3-dioxolane(DOL) could penetrate into the porous LLZTO framework for its excellent *** subsequent in situ polymerization process by thermal treatment could completely fill the internal pores and improve the interfacial contact with *** resulting 3D composite electrolyte with dual continuous Li+transport channels in ceramic and polymer components exhibits high ionic conductivity of 2.8 × 10^(-4) S·cm^(-1) at room temperature and low Li/electrolyte interfacial resistance of 94 Ω·cm^(2) at 40 ℃.The corresponding Li/Li symmetric cell delivers stable voltage profiles for over 600 h under 0.1 and 0.2 mA·cm^(-2).The solid-state Li/LiFePO_(4) battery shows superior rate and cycling performance under 0.1 C and 0.2 *** work guides the preparation of composite electrolyte with dual continuous Li+conductive paths as well as high ceramic ratio and interface modification strategy for solid-state Li metal battery.

关键词： Garnet electrolyte 1,3-dioxolane(DOL) In situ polymerization Three-dimensional(3D)composite electrolyte Continuous Li^(+)conductive channel

Phase-field model of precipitation processes with coherency loss

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npj Computational Materials 2021年第1期7卷 338-348页

作者： Tian-le Cheng You-hai Wen National Energy Technology Laboratory AlbanyORUSA leidos Research Support Team AlbanyORUSA

A phase-field model is proposed to simulate coherency loss coupled with microstructure evolution.A special field variable is employed to describe the degree of coherency loss of each particle and its evolution is governed by a Ginzburg-Landau type kinetic *** the sake of computational efficiency,a flood-fill algorithm is introduced that can drastically reduce the required number of field variables,which allows the model to efficiently simulate a large number of particles sufficient for characterizing their statistical features during Ostwald *** model can incorporate size dependence of coherency loss,metastability of coherent particles,and effectively incorporate the underlying mechanisms of coherency loss by introducing a so-called differential energy *** model is applied to simulate coarsening of Al3Sc precipitates in aluminum alloy and comprehensively compared with *** results clearly show how the particle size distribution is changed during coherency loss and affects the coarsening rate.

关键词： coherency alloy microstructure

Prevalence of asthenopia and its risk factors in Chinese college students

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International Journal of Ophthalmology(English edition) 2013年第5期6卷 718-722页

作者： Cheng-Cheng Han rong Liu Ru-Ru Liu Zhong-hai Zhu rong-Bin Yu le Ma School of Public Health Xi'an Jiaotong University College of Medicine Xi'an Center for Disease Control and Prevention

·AIM: To determine the prevalence of asthenopia and identify any associated risk factors in the college students in Xi’an, China. · METHODS: From April to September 2012, 1 500 students from five universities in Xi’an were selected according to a multi -stage stratified cluster sampling method. Data on demographic features, lifestyle or dietary habits, health status, living environment conditions, sleep and mental status, and asthenopia symptoms were collected through a self -administered validated questionnaire. Univariate logistic regression and multivariate logistic regression analysis modified by the factor analysis were performed to evaluate risk factors for asthenopia. ·RESULTS: Fifty-seven percent of the college students complained of asthenopia. Statistically significant risk factors for asthenopia in the univariate analysis included 13 variables. Multivariate analysis revealed a significant relationship between the use of computer and asthenopia (OR 1.21, 95% CI: 1.09 to 1.35). Good sleep and mental status (OR 0.86, 95% CI: 0.76 to 0.97), good living environment conditions (OR 0.67, 95% CI: 0.60 to 0.76), and high intake of green leafy vegetables (OR 0.89, 95% CI: 0.80 to 0.98) were found to be strong predictors of decreasing the occurrence of asthenopia complaints. ·CONCLUSION: Asthenopia symptom appeares to be common among college students; and it is strongly associated with computer use, psychosocial state, environment conditions and dietary habits, suggesting that additional studies are warranted to verify these risk factors and establish prevention guidelines, especially for college students. ·

关键词： asthenopia risk factor epidemiological feature college student

The effects of social security expenditure on reducing income inequality and rural poverty in China

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Journal of Integrative Agriculture 2021年第4期20卷 1060-1067页

作者： YU le-rong LI Xiao-yun College of Humanities and Development China Agricultural UniversityBeijing 100193P.R.China

Social security has,as one of its primary aims,the provision of financial support to those deemed to be poor or facing the threat of *** on China's national statistical data covering social insurance,social assistance,and social welfare between the period 1978–2018,this paper evaluates the effect of social security expenditure in reducing income inequality and rural poverty with cointegration *** was found that there is a positive correlation between social security expenditure and the income gap of urban and rural residents in the long run,but the effect is very limited;nearly 99%of the changes of the urban–rural income gap come from its own *** research also shows that the elasticity of rural poverty incidence to social security expenditure is–0.2255,which indicates social security expenditure helps reduce rural absolute *** on these findings,the policy implications can be that much social security expenditure and a more equitable social security system should be *** will become one of the major anti-poverty strategies after 2020 in China when we win the battle against absolute poverty.

关键词： social security expenditure income inequality rural poverty reduction in China

Microglia lactylation in relation to central nervous system diseases

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Neural Regeneration Research 2025年第1期20卷 29-40页

作者： Hui Yang Nan Mo le Tong Jianhong Dong Ziwei Fan Mengxian Jia Juanqing Yue Ying Wang School of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Clinical Laboratory The Fourth Clinical Medical College of Zhejiang University of Traditional Chinese Medicine(Hangzhou First People’s Hospital)HangzhouZhejiang ProvinceChina College of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK Department of Orthopedics(Spine Surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina

The development of neurodegenerative diseases is closely related to the disruption of central nervous system ***,as innate immune cells,play important roles in the maintenance of central nervous system homeostasis,injury response,and neurodegenerative *** has been considered a metabolic waste product,but recent studies are revealing ever more of the physiological functions of *** is an important pathway in lactate function and is involved in glycolysis-related functions,macrophage polarization,neuromodulation,and angiogenesis and has also been implicated in the development of various *** review provides an overview of the lactate metabolic and homeostatic regulatory processes involved in microglia lactylation,histone versus non-histone lactylation,and therapeutic approaches targeting ***,we summarize the current research on microglia lactylation in central nervous system diseases.A deeper understanding of the metabolic regulatory mechanisms of microglia lactylation will provide more options for the treatment of central nervous system diseases.

关键词： brain central nervous system glycolysis immune response inflammation lactate metabolism lactate lactylation microglia neurodegenerative diseases

Synthesis of hierarchically porous carbon materials by zinc salts-assisted carbonization of biomass and organic solid wastes

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Particuology 2024年第1期84卷 45-52页

作者： le-le Zhang lei Tong Yanwei Ding Wanqun Zhang hai-Wei Liang Hefei National Research Center for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei230026China

Hierarchically porous carbons(HPCs)with multimodal pores have attracted considerable attention due to their unique physical and chemical properties and various application potentials in heterogeneous catalysis,environmental treatment,and energy storage and ***,we report a general and simple zinc salts-assisted method for the synthesis of HPCs with varied porosity and chemical func-tionalities by the direct carbonization of diverse biomass and *** the carbonization,zinc salts are thermally decomposed into nanoparticles that serve as in-situ templates to introduce nanopores in *** prepared HPCs exhibit high specific surface areas(up to 2432 m2 g-1),large pore volumes(up to 4.30 cm^(3)g^(-1)),and broad pore size ***,the zinc salts can be recovered and recycled,supporting the sustainable production of HPCs on large *** prepared HPCs-supported catalysts with atomically dispersed metal sites exhibit promising electrocatalytic performance for the oxygen reduction reaction.

关键词： Hierarchical porous carbon Zinc salts Biomass Wastes Electrocatalysis