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Nano Research 2023年第7期16卷 9022-9030页

作者： Jun Qi Xinyu Zhong huiyan zeng Chao Wang Zhongfei Liu Jiajun Chen Long Gu Enna Hong Mengxian Li Jiong Li Chunzhen Yang School of Materials Shenzhen Campus of Sun Yat-Sen UniversityShenzhen 518107China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

Understanding the dynamic structural and chemical evolutions at the catalyst-electrolyte interfaces is crucial for the development of active and stable electrocatalysts.In this work,β-Li_(2)IrO_(3)is employed as a model catalyst for the oxygen evolution reaction(OER).Its elastic three-dimensional Ir-O framework enables us to investigate the Li^(+)cation dissolution-induced structure evolutions and the formation mechanism of amorphous IrO_(x)species.Electrochemical measurements by rotating ring disk electrode(RRDE)reveal that up to 60%of the measured OER current can be ascribed to catalyst degradation.A series of in-situ X-ray diffraction spectroscopy(XRD),X-ray absorption spectroscopy(XAS),and Raman spectroscopy are conducted.Structure vibration is observed with oxidation states of Ir being reduced abnormally during OER at high potentials.It’s hypothesized that the reversible proton intercalations are responsible for the Ir turn-over mechanism.Results of this work demonstrate a stable and elastic iridate structure and reveal the initial catalyst degradation behaviors during OER in acid media.

关键词： oxygen evolution reaction structure evolution amorphization acid media catalyst degradation

基于中医传承辅助系统分析中医药治疗糖尿病下肢血管病变的组方规律

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西北药学杂志 2024年第3期39卷 209-212页

作者：杨彩凤张锦明赵玲丁源陈丽春王李子牛曾慧妍广州中医药大学第二附属医院内分泌科广州510006 广州中医药大学第二临床医学院广州510405

目的挖掘国内关于中医药治疗糖尿病下肢血管病变的文献,探索糖尿病下肢血管病变的中药组方用药规律及特点。方法通过检索维普、万方和CNKI等数据库,筛选纳入中医药治疗糖尿病下肢血管病变的文献,运用中医传承辅助系统(Traditional Chine... 详细信息

目的挖掘国内关于中医药治疗糖尿病下肢血管病变的文献,探索糖尿病下肢血管病变的中药组方用药规律及特点。方法通过检索维普、万方和CNKI等数据库,筛选纳入中医药治疗糖尿病下肢血管病变的文献,运用中医传承辅助系统(Traditional Chinese Medicine Inheritance Support System,TCMISS)2.5软件建立数据库并进行数据分析。结果共筛选出54个中药复方用于治疗糖尿病下肢血管病变,其中出现频次超过20次的药物分别为黄芪、川芎、当归、丹参、桂枝、水蛭、牛膝和地龙,进一步挖掘出44个高频药对,提炼核心组合12个,形成新处方5个。结论借助TCMISS软件定量分析药物之间的关联性,分析各医家治疗糖尿病下肢血管病变的用药经验和方药规律,凝练出糖尿病下肢血管病变的治疗新处方。

关键词：中医辅助传承系统(TCMISS) 糖尿病下肢血管病变组方规律

Dynamic coupling of ferrihydrite transformation and associated arsenic desorption/redistribution mediated by sulfate-reducing bacteria

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Journal of Environmental Sciences 2024年第1期135卷 39-50页

作者： Wenjing Zhou huiyan Zhu Shiwen Hu Bowei Zhang Kun Gao Zhi Dang Chongxuan Liu State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSouth China University of TechnologyGuangzhou 510006China

Sulfate-reducing bacteria play an important role in the geochemistry of iron(oxyhydr)oxide and arsenic(As)in natural environments;however,the associated reaction processes are yet to be fully understood.In this study,batch experiments coupled with geochemical,spectroscopic,microscopic,and thermodynamic analyses were conducted to investigate the dynamic coupling of ferrihydrite transformation and the associated As desorption/redistribution mediated by Desulfovibrio vulgaris(D.vulgaris).The results indicated that D.vulgaris could induce ferrihydrite transformation via S^(2-)-driven and direct reduction processes.In the absence of SO_(4)^(2-),D.vulgaris directly reduced ferrihydrite,and As desorption and re-sorption occurred simultaneously during the partial transformation of ferrihydrite to magnetite.The increase in SO_(4)^(2-)loading promoted the S^(2-)-driven reduction of ferrihydrite and accelerated the subsequent mineralogical transformation.In the low and medium SO_(4)^(2-)treatments,ferrihydrite was completely transformed to a mixture of magnetite and mackinawite,which increased the fraction of As in the residual phase and stabilized As.In the high SO_(4)^(2-)treatment,although the replacement of ferrihydrite by only mackinawite also increased the fraction of As in the residual phase,22.1%of the total As was released into the solution due to the poor adsorption affinity of As to mackinawite and the conversion of As^(5+)to As^(3+).The mechanisms of ferrihydrite reduction,mineralogy transformation,and As mobilization and redistribution mediated by sulfate-reducing bacteria are closely related to the surrounding SO_(4)^(2-)loadings.These results advance our understanding of the biogeochemical behavior of Fe,S,and As,and are helpful for the risk assessment and remediation of As contamination.

关键词： Sulfate-reducing bacteria Arsenic Ferrihydrite Transformation Redistribution

Reaction pathways and selectivity in the chemo-catalytic conversion of cellulose and its derivatives to ethylene glycol:A review

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Chinese Journal of Chemical Engineering 2024年第2期66卷 310-331页

作者： Yao Li Yuchun Zhang Zhiyu Li huiyan Zhang Peng Fu College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000China Key Laboratory of Energy Thermal Conversion and Control Ministry of EducationSchool of Energy and EnvironmentSoutheast UniversityNanjing 210096China

Biomass-to-ethylene glycol is an effective means to achieve high-value utilisation of cellulose but is hindered by low conversion efficiency and poor catalyst activity and stability.Glucose and cellobiose are derivatives of cellulose conversion to ethylene glycol,and it is found that studying the reaction process of both can help to understand the reaction mechanism of cellulose.It is desirable to develop a reusable,highly active catalyst to convert cellulose into ethylene glycol.This ideal catalyst might have one or more active sites described the conversion steps above.Here,we discuss the catalyst development of celluloseto-ethylene glycol,including tungsten,tin,lanthanide,and other transition metal catalysts,and special attention is given to the reaction mechanism and kinetics for preparing ethylene glycol from cellulose,and the economic advantages of biomass-to-ethylene glycol are briefly introduced.The insights given in this review will facilitate further development of efficient catalysts,for addressing the global energy crisis and climate change related to the use of fossil fuels.

关键词： Ethylene glycol Cellulose Catalyst Retro-aldol condensation Hydrolysis Kinetics

动物生物安全实验室废弃物分类高压灭菌程序探索

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中国动物检疫 2024年第2期41卷 22-26页

作者：曾荟燕王团结李婉清李强孟伯龙郭桐同李倩琳杨成岗门星光张广川中国兽医药品监察所北京100081

为探索动物生物安全实验室不同种类废弃物合理的高压灭菌程序,探讨脉动真空灭菌器灭菌时间和脉动参数对灭菌效果的影响,以化学指示卡和生物指示剂为判断标准,研究了不同种类废弃物(动物尸体、粪便以及防护服、利器盒等一般废弃物)的灭... 详细信息

为探索动物生物安全实验室不同种类废弃物合理的高压灭菌程序,探讨脉动真空灭菌器灭菌时间和脉动参数对灭菌效果的影响,以化学指示卡和生物指示剂为判断标准,研究了不同种类废弃物(动物尸体、粪便以及防护服、利器盒等一般废弃物)的灭菌程序。在程序设置方面,以灭菌温度121℃,脉动4次,排空上限80 kPa为灭菌固定参数,通过设置不同的灭菌时间和脉动下限,探索有效灭菌程序。结果显示:当灭菌时间为90 min,排空下限为-10 kPa时,猪、牛、羊等大动物尸体及其粪便灭菌合格;当排空下限为-80 kPa,灭菌时间分别为30、60、120 min时,一般废弃物、小动物尸体、禽类粪便灭菌合格。结果表明,通过调整灭菌时间和脉动参数,对不同种类废弃物进行分类高压,灭菌效果更加理想。本研究为动物生物安全实验室的废弃物处理提供了参考。

关键词：动物生物安全实验室废弃物高压灭菌灭菌时间脉动参数

Micro-nanoarchitectonic of aluminum-hydrogel propellant with static stability and dynamic rheology

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 87-96页

作者： huiyan Guo Huaiyu Li Hongzhi Zhang Lun Pan Chengxiang Shi Kang Xue Xiangwen Zhang Ji-Jun Zou Key Laboratory for Advanced Fuel and Propellant of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

The aluminum-water system is a promising propellant due to high energy and low signal characteristics,and the gel form is easier to store and utilize.In this work,hydrogels of water and aluminum particles were prepared using the low-molecular-weight gellant agarose.The various physical properties of gel systems,including the water loss rate,phase transition temperature,and centrifugal stability at different gellant and aluminum contents,were examined.Rheological properties were assessed through shear thinning tests,thixotropy tests,strain sweep analysis,and frequency sweep experiments.The microstructure of the gel was obtained through scanning electron microscopy images.The results show that the aluminum-hydrogel network structure is composed of micron-scale aluminum and agarose nanosheets,and the unique micro-nanostructure endows the gel with excellent mechanical strength and thermal stability,which improve with increasing gellant and aluminum contents.Notably,the gel with 2% agarose and 20% aluminum had the best performance;the storage modulus reached 90647 Pa,which was within the linear viscoelastic region,and the maximum withstand pressure was 111.2 kPa,which was 118.8% greater than that of the pure hydrogel.Additionally,the gel demonstrates remarkable shear thinning behavior and can undergo gel-sol transformation upon shearing or heating to exceeding 114℃.

关键词： aluminum-water propellant gelled propellant rheological property mechanical strength

Achieving superior performance in powder-metallurgy near-βtitanium alloy by combining hot rolling and rapid heat treatment followed by aging

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Journal of Materials Science & Technology 2024年第4期171卷 24-36页

作者： Fucheng Qiu Tuo Cheng Yuchao Song Orest M.Ivasishin Dmytro G.Savvakin Guangyu Ma huiyan Xu College of Materials Science and Engineering Jilin UniversityChangchun 130025China International Center of Future Science Jilin UniversityChangchun 130025China G.V.Kurdyumov Institute for Metal Physics KyivUkraine College of Biological and Agricultural Jilin UniversityChangchun 130025China

Heat treatment plays an important role in tailoring the mechanical properties of powder-metallurgy(PM)titanium alloys.However,only limited work about the rapid heat treatment(RHT)of PM titanium alloys has been reported.In this work,RHT was applied to PM Ti-5Al-5Mo-5V-1Cr-1Fe alloy after hot rolling to study the evolution of its mechanical properties and the influence of residual pores on its properties.Through hot rolling and annealing,a fine and uniformα+βstructure with few residual pores is ob-tained.During RHT,the primaryαdissolves gradually and completes in theβregion,and theβgrains then grow,resulting in the continuous decrease in elongation after aging.Moreover,the tensile strength first increases and then decreases with increasing RHT temperature,owing to the increase in volume fraction of secondaryαinα+βregion and theβgrain growth inβregion.In contrast to the RHT of cast-and-wrought titanium,the negative influence of residual pores lowers the RHT temperature for obtaining the highest tensile strength to a temperature below theβ-transus temperature.Despite the negative influence of the residual pores,retained primaryαand fineβgrains with fine secondaryαinside contribute to achieving a good strength/ductility balance(1570 MPa and 6.1%,respectively).Addi-tionally,although at higher cycles to failure,the negative influence of residual pores increases as it affects the crack initiation zone at the subsurface,the good resistance of secondaryαto fatigue crack propaga-tion still enhances the fatigue strength considerably(about 300 MPa).This work suggests a cost-effective strategy to produce titanium alloys with high performance.

关键词： Rapid heat treatment Powder metallurgy Mechanical properties Near-βtitanium Residual pores

析氧反应中催化剂-电解质界面的质子动力学研究

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Chinese Journal of Catalysis 2022年第1期43卷 139-147页

作者：曾辉炎曾衍铨漆俊顾龙洪恩纳司锐杨纯臻中山大学材料学院广东深圳518107 深圳综合粒子设施研究院广东深圳518107

电催化水分解是一种可持续的绿色产氢技术,该技术在工业化的大规模应用急需开发高效稳定的非贵金属催化剂,用于提高析氧反应(OER)的反应速率.研究发现,钙钛矿氧化物是优异的OER催化剂,但是对于发生在催化剂-电解质固液界面上的反应机理... 详细信息

电催化水分解是一种可持续的绿色产氢技术,该技术在工业化的大规模应用急需开发高效稳定的非贵金属催化剂,用于提高析氧反应(OER)的反应速率.研究发现,钙钛矿氧化物是优异的OER催化剂,但是对于发生在催化剂-电解质固液界面上的反应机理仍有争论.目前普遍认为,在OER反应过程中,水分子吸附在金属氧化物催化剂表面的金属活性中心上,并进行连续四步的质子耦合电子转移步骤(PCET),通过“吸附演化机制”(AEM)的方式氧化成氧气分子.根据该机制,调整钙钛矿材料的电子结构来控制表面性质已被广泛认为是提高OER活性的有效策略.然而近期的研究发现,一些高活性钙钛矿催化剂如La_(1-x)Sr_(x)CoO_(3)(LSCO,x≥0.5)在可逆氢电极(RHE)体系中的OER电催化活性表现出强烈的pH依赖性,从而提出了一种晶格氧参与氧化的反应机制(LOM).根据该机理,OER所产生的氧气分子不仅来自电解液中的水分子,而且氧化物催化剂中晶格氧也可能直接参与O‒O健的生成.从传统的AEM机制到具有高活性的LOM反应机制,速率限制步骤(RLS)由O‒O键生成(O(ads)+OH–→OOH(ads)+e–)转变为‒OOHads的脱质子步骤(OOH(ads)+OH–→OO(ads)+H++e–).而且,RLS中涉及到质子转移,表明解耦的PCET可能存在.尽管一些实验和理论研究已经证实脱质子步骤对于高活性的OER电催化剂的重要性,但需要进一步的工作来充分阐明质子动力学在催化剂-电解质界面以及RLS转变过程中的作用.本文系统探究了催化剂表面质子动力学对于OER反应机理的影响,提出一种研究催化剂表面质子动力学的实验方案,揭示了钙钛矿氧化物的电子结构、质子动力学和催化剂-电解质界面上相关的OER机制之间的潜在关联.采用固相法制备了La_(0.5)Sr_(0.5)CoO_(3)-δ(LSCO),LaCoO_(3),LaFeO_(3)和LaNiO_(3)等4种钙钛矿催化剂作为模型催化剂.电化学测试表明,LSCO和LaNiO_(3)催化剂的OER电催化活性具有pH依赖行为,而LaCoO_(3)和LaFeO_(3)的OER电催化活性对pH不敏感.H/D动力学同位素效应(KIE)的研究显示,D_(2)O电解液可以显著减缓LSCO和LaNiO_(3)催化剂表面的质子转移动力学,降低其OER电催化活性.反之,D2O电解液对LaCoO_(3)和LaFeO_(3)的OER活性影响不大.此外,研究也发现,Pi基团的表面功能化可以有效地增强LSCO和LaNiO_(3)催化剂表面的质子转移动力学,提高其OER电催化活性.以上的测试结果为判别不同钙钛矿氧化物上协同和非协同PCET路径的限速步骤(RLS)提供了全面的依据.对于电荷转移能较小的钙钛矿氧化物,如LSCO和LaNiO_(3),其OER过程通过非协同PCET步骤进行,其活性受催化剂表面质子动力学的影响较大,RLS为‒OOHads的脱质子步骤,体现出晶格氧参与水氧化的LOM机制.而对于LaCoO_(3)和LaFeO_(3)等活性较差并且电荷转移能较大的钙钛矿催化剂,OER过程遵循经典的AEM机制,RLS由O‒O键的形成来调控,OER性能受界面质子动力学的影响较小.本文对于确定OER反应路径,准确描述OER反应机理和动力学具有重要意义.

关键词：电催化水氧化氧析出反应动力学同位素效应质子耦合电子转移反应机理

Application Strategies of Automatic Addressable Single-Lamp Control Technology in Tunnel Lighting

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Journal of World Architecture 2024年第2期8卷 90-95页

作者： huiyan Yang China Merchants Chongqing Communications Technology Research&Design Institute Co. LTD.Chongqing 400067China

The article mainly studies the application strategy of automatic addressable single-lamp control technology in tunnel lighting.It encompasses an introduction to this technology,an analysis of the tunnel lighting system using automatic addressable single-lamp control technology,and outlines the main development direction for this technology in modern tunnel lighting.The aim is to offer insights that can inform the rational deployment of this technology,thereby enhancing the lighting control effectiveness in modern tunnels and meeting their specific lighting requirements more effectively.

关键词： Tunnel lighting Automatic addressable single-lamp control technology System design Cascade control

米非司酮治疗高龄促肾上腺皮质激素依赖性库欣综合征1例

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中华内科杂志 2022年第5期61卷 574-577页

作者：吴露露曾慧妍唐咸玉范冠杰广东省中医院内分泌科广州510120

促肾上腺皮质激素(ACTH)依赖性库欣综合征(Cushing syndrome,CS)首选手术治疗。但当定位不明确或无法耐受手术时,药物治疗是重要的备选方案。本例为88岁高龄ACTH依赖性CS 患者,经米非司酮治疗后该患者CS相关症状及体征改善,降压药物减量... 详细信息

促肾上腺皮质激素(ACTH)依赖性库欣综合征(Cushing syndrome,CS)首选手术治疗。但当定位不明确或无法耐受手术时,药物治疗是重要的备选方案。本例为88岁高龄ACTH依赖性CS 患者,经米非司酮治疗后该患者CS相关症状及体征改善,降压药物减量,降糖药物停用,血钾稳定。提示对于高龄中重度CS患者,如果手术不成功或不能耐受手术,米非司酮是一种可考虑的治疗选择。

关键词：库欣综合征米非司酮老年人