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One-step conversion of methane and formaldehyde to ethanol over SA-FLP dual-active-site catalysts: A DFT study

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Chinese Chemical Letters 2024年第4期35卷 544-548页

作者： Tao Ban Xi-Yang Yu Hai-Kuo Tian zheng-qing huang Chun-Ran Chang Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an 710049China Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization School of Chemistry and Chemical EngineeringYulin UniversityYulin 719000China

One-step conversion of methane and formaldehyde into ethanol is a 100% atom-efficient process for carbon resources utilization and environment protection but still faces eminent challenges due to the lacking of efficient catalysts. Therefore, developing active and stable catalysts is crucial for the co-conversion of methane and formaldehyde. Herein, twelve kinds of “Single-Atom”-“Frustrated Lewis Pair”(SA-FLP)dual-active-site catalysts are designed for the direct conversion of methane and formaldehyde to ethanol based on density functional theory(DFT) calculations and microkinetic simulations. The results show that the SA-FLP dual active sites can simultaneously activate methane at the SA site and activate formaldehyde at the FLP site. Among the twelve designed SA-FLP catalysts, Fe1-FLP shows the best performance in the co-conversion of methane and formaldehyde to ethanol with the rate-determining barrier of 1.15 e *** is proved as the main product with the turnover frequency of 1.32 × 10^(-4)s^(-1)at 573 K and 3 *** work provides a universal strategy to design dual active sites on metal oxide materials and offers new insights into the effective conversion of methane and formaldehyde to desired C_(2) chemicals.

关键词： Single-atom Frustrated Lewis pairs Methane conversion Dual active sites Ethanol synthesis

Role of surface frustrated Lewis pairs on reduced CeO2(110)in direct conversion of syngas

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Chinese Journal of Catalysis 2020年第12期41卷 1906-1915页

作者： zheng-qing huang Teng-Hao Li Bolun Yang Chun-Ran Chang Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049ShaanxiChina

Direct syngas conversion to light olefins on bifunctional oxide-zeolite(OX-ZEO)catalysts is of great interest to both academia and industry,but the role of oxygen vacancy(Vo)in metal oxides and whether the key intermediate in the reaction mechanism is ketene or methanol are still not *** address these two issues,we carry out a theoretical study of the syngas conversion on the typical reducible metal oxide,CeO2,using density functional theory *** results demonstrate that by forming frustrated Lewis pairs(FLPs),the VOs in CeO2 play a key role in the activation of H2 and *** activation of H2 on FLPs undergoes a heterolytic dissociative pathway with a tiny barrier of 0.01 eV,while CO is activated on FLPs by combining with the basic site(O atom)of FLPs to form CO2^2-.Four pathways for the conversion of syngas were explored on FLPs,two of which are prone to form ketene and the other two are inclined to produce methanol suggesting a compromise to resolve the debate about the key intermediates(ketene or methanol)in the *** constant calculations showed that the route initiating with the coupling of two CO*into OCCO*and ending with the formation of ketene is the dominant pathway,with the neighboring FLPs playing an important role in this ***,our study reveals the function of the surface FLPs in the activation of H2 and CO and the reaction mechanism for the production of ketene and methanol for the first time,providing novel insights into syngas conversion over OX-ZEO catalysts.

关键词： Syngas conversion Light olefins Oxide-zeolite Frustrated Lewis pairs CeO2

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The role of axon guidance molecules in the pathogenesis of epilepsy

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Neural Regeneration Research 2025年第5期20卷 1244-1257页

作者： zheng Liu Chunhua Pan Hao huang Department of Neurology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that axon guidance molecules play a role in the structural and functional modifications of neural networks and that the dysregulation of these molecules is associated with epilepsy susceptibility. In this review, we discuss the essential role of axon guidance molecules in neuronal activity in patients with epilepsy as well as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, we examine the relationship between axon guidance molecules and neuroinflammation, as well as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that axon guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding axon growth and the establishment of synaptic connections. Deviations in their expression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural networks is a significant characteristic of epilepsy, with axon guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance between excitation and inhibition within a neural network, thereby increasing the risk of overexcitation and the development of epilepsy. Inflammatory signals can regulate the expression and function of axon guidance molecules, thus influencing axonal growth, axon orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review delves into the mechanisms associated with

关键词： axon guidance drug-resistant epilepsy epilepsy nerve regeneration nervous system diseases neural pathways neuroinflammatory diseases neuronal plasticity neurons synaptic remodeling

Preparation of FeCoNi medium entropy alloy from Fe^(3+)-Co^(2+)-Ni^(2+)solution system

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 92-101页

作者： Zongyou Cheng qing Zhao Mengjie Tao Jijun Du Xingxi huang Chengjun Liu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education) Shenyang 110819China

In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical *** controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower *** this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen *** phases and magnetic properties of FeCoNi medium entropy alloy were *** showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal *** alloy prepared by hydrogen reduction was uniform and showed a relatively high ***,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity.

关键词： medium entropy alloy sol-gel co-precipitation carbothermal hydrogen reduction

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基于空间分形特征的城市群实体空间识别方法

地理科学进展 2017年第6期36卷 677-684页

作者：刘飞郑新奇黄晴中国地质大学(北京)信息工程学院北京100083

城市群是城市地理学的重要研究领域,对城市群的实体空间进行界定识别是研究城市群的前提和基础。城市群作为众多城镇的集群,前人对城市群的空间识别主要是以城市为单元进行的,缺少对识别单元空间形态的考虑。城市群实体空间的形态具有... 详细信息

城市群是城市地理学的重要研究领域,对城市群的实体空间进行界定识别是研究城市群的前提和基础。城市群作为众多城镇的集群,前人对城市群的空间识别主要是以城市为单元进行的,缺少对识别单元空间形态的考虑。城市群实体空间的形态具有自相似性,空间分形特征可作为自相似性的表征工具,通过对空间分形特征的分析、识别及提取,可以实现对空间对象基于形态的客观测度。本文借鉴单个城市其边界的相关识别方法,从不同尺度的空间最小可识别单元出发,测度城市群城镇空间形态的分形特征,并据此提出了城市群城镇的客观识别方法。该方法利用城镇的空间分形特征识别归属于城市群的城镇,通过空间最小可识别单元的变化得到不同的城镇规模并获取城市群城镇的空间分形特征,再以此为基础对空间分形特征的存在范围进行识别,将其映射于空间最终实现对城市群城镇的识别,进而得到城市群在空间上的分布状况。本文将该方法应用于京津冀城市群,基于2016年Landsat卫星遥感影像,实现了对京津冀城市群构成城镇的识别,为界定城市群的实体空间提供了一次有益尝试。

关键词：城市群实体空间空间识别空间形态分形特征

Experimental Study on Diesel Spray and Flame Asymmetry Characteristics of Dual-Orifice Nozzles for a Medium-Speed Engine

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Journal of Thermal Science 2025年第1期34卷 303-322页

作者： JU Dehao LIU Rui zheng Liang DENG Jiahui ZHANG Wenzheng HUO Jinlu huang Li Shanghai Marine Diesel Engine Research Institute National Key Laboratory of Marine Engine Science and Technology Key Laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong University

The asymmetry of the multi-orifice spray will cause uneven heat load of the marine diesel engine,thereby affecting its working performance and service ***,an in-depth understanding of the spray and flame characteristics of multi-orifice nozzles will guide the optimization of the nozzle structure,needle design and diesel atomization and combustion *** this reason,four groups of dual-orifice nozzles with different hole diameters(0.1-0.55 mm) and mass flow rates covering the typical marine medium-speed diesel injections are designed and customized,and the constant volume chamber(CVC) with high temperature and pressure is used to simulate the actual in-cylinder working conditions of the diesel engine for the spray visualization *** study the asymmetry of the fuel sprays discharged from a diesel injector,the multi-orifice nozzle is simplified as a dual-orifice nozzle in this *** with X-ray Computed Tomography(CT) imaging technology,the influences of the nozzle internal structure on the spray and flame asymmetry are studied in the constructed supercritical *** is found that the asymmetry of the inlet angle and the equivalent length-diameter ratio is positively correlated with the inconsistency of the dual *** an increase in the injection pressure and nozzle diameter,the asymmetry of the dual spray becomes more pronounced,resulting in greater disparities in the ignition delay times and ignition positions of the two ***,the increase in nozzle diameter also leads to combustion instability,resulting in a flame with a serrated *** the increase of ambient temperature,the proportion of liquid phase in the jet decreases and the relative density of spray front decreases.

关键词： atomization dual-orifice nozzle nozzle structure spray flame asymmetry

Reaction Mechanism of One-Step Conversion of Ethanol to 1,3-Butadiene over Zn-Y/BEA and Superior Catalysts Screening

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Chinese Journal of Chemical Physics 2022年第4期35卷 600-610,I0004-I0009,I0149页

作者： Shu-Xuan Dang Han-Xuan Liu Tao Ban Xin Gao zheng-qing huang Dong-Yuan Yang Chun-Ran Chang Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization School of Chemistry and Chemical EngineeringYulin UniversityYulin 719000China Shaanxi Yanchang Petroleum(Group)Corp.Ltd. Xi’an 710065China

The one-step conversion of ethanol to 1,3-butadiene has achieved a breakthrough with the development of beta zeolite supported dual metal ***,the reaction mechanism from ethanol to butadiene is complex and has not yet been fully elucidated,and no catalyst screening effort has been done based on central metal *** this work,density functional theory(DFT)calculations were employed to study the mechanism of one-step conversion of ethanol to butadiene over ZnY/BEA *** results show that ethanol dehydrogenation prefers to proceed on Zn site with a reaction energy of 0.77 eV in the rate-determining step,and the aldol condensation to produce butadiene prefers to proceed on Y site with a reaction energy of 0.69 eV in the rate-determining *** on the mechanism revealed,six elements were selected to replace Y for screening superior combination of Zn-M/BEA(M=Sn,Nb,Ta,Hf,Zr,Ti;BEA:beta polymorph A)for this *** a result,Zn-Y/BEA(0.69 eV)is proven to be the most preferring catalyst compared with the other six ones,and Zn-Zr/BEA(0.85 eV),Zn-Ti/BEA(0.87 eV),and Zn-Sn/BEA(0.93 eV)can be potential candidates for the conversion of ethanol to *** work not only provides mechanistic insights into one-step catalytic conversion of ethanol to butadiene over Zn-Y/BEA catalyst but also offers more promising catalyst candidates for this reaction.

关键词： Ethanol 1,3-Butadiene Zn-Y/BEA Aldol condensation Density functional theory

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期68卷 369-376页

作者： Song-Meng Wang Hao Nian Yan-Fang Wang Li-Shuo zheng Yu-Tao zheng Yi-Wei Dong Liping huang Xiaoping Wang Wei Jiang Liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

关键词： host-guest interaction hydrophobic effect endo-functionalized cavity mutation pyridine

Cholesterol metabolism: physiological versus pathological aspects in intracerebral hemorrhage

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Neural Regeneration Research 2025年第4期20卷 1015-1030页

作者： Ruoyu huang Qiuyu Pang Lexin zheng Jiaxi Lin Hanxi Li Lingbo Wan Tao Wang Department of Forensic Science School of Basic Medicine and Biological SciencesSuzhou Medicine College of Soochow UniversitySuzhouJiangsu ProvinceChina

Cholesterol is an important component of plasma membranes and participates in many basic life functions,such as the maintenance of cell membrane stability,the synthesis of steroid hormones,and *** plays a key role in the establishment and maintenance of the central nervous *** brain contains 20%of the whole body’s cholesterol,80%of which is located within myelin.A huge number of processes(e.g.,the sterol regulatory element-binding protein pathway and liver X receptor pathway)participate in the regulation of cholesterol metabolism in the brain via mechanisms that include cholesterol biosynthesis,intracellular transport,and *** brain injuries or diseases involving crosstalk among the processes above can affect normal cholesterol metabolism to induce detrimental ***,we hypothesized that cholesterol-related molecules and pathways can serve as therapeutic targets for central nervous system *** hemorrhage is the most severe hemorrhagic stroke subtype,with high mortality and *** cholesterol levels are associated with the risk of intracerebral ***,secondary pathological changes after intracerebral hemorrhage are associated with cholesterol metabolism dysregulation,such as neuroinflammation,demyelination,and multiple types of programmed cell *** cholesterol accumulation in the brain has been found after intracerebral *** this paper,we review normal cholesterol metabolism in the central nervous system,the mechanisms known to participate in the disturbance of cholesterol metabolism after intracerebral hemorrhage,and the links between cholesterol metabolism and cell *** also review several possible and constructive therapeutic targets identified based on cholesterol metabolism to provide cholesterol-based perspectives and a reference for those interested in the treatment of intracerebral hemorrhage.

关键词： cell death cholesterol metabolism intracerebral hemorrhage myelination therapeutic target