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M42高速钢电渣重熔及锻造退火后碳化物的析出

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钢铁 2017年第7期52卷 68-75页

作者：罗乙娲郭汉杰孙晓林北京科技大学冶金与生态工程学院北京100083 高端金属材料特种熔炼与制备北京市重点实验室北京100083 钢铁研究总院高温材料研究所北京100081

通过X射线衍射分析、光学显微镜和透射式电子显微镜观察以及相关热力学计算,对比研究了M42高速钢电渣锭及锻后退火两种状态所析出碳化物的类型、尺寸、分布及析出条件。得出M42高速钢电渣锭中的碳化物主要为Mo_2C亚稳态碳化物和少量Cr_7... 详细信息

通过X射线衍射分析、光学显微镜和透射式电子显微镜观察以及相关热力学计算,对比研究了M42高速钢电渣锭及锻后退火两种状态所析出碳化物的类型、尺寸、分布及析出条件。得出M42高速钢电渣锭中的碳化物主要为Mo_2C亚稳态碳化物和少量Cr_7C_3碳化物,Mo_2C碳化物尺寸较大,主要呈层片状、纤维状和棒状沿晶界析出。锻造退火后的M42高速钢中碳化物类型主要为Cr_7C_3,VC和Fe_2Mo_4C,平均尺寸小于10μm且分布均匀,形态以方形、不规则球形和小颗粒为主。M42高速钢电渣锭中的Mo_2C在锻造过程中可以分解为Fe_2Mo_4C和VC。根据冶金热力学计算得出,Mo_2C和VC在固液两相区析出,析出温度分别为1 229和1 222℃;Cr_7C_3在固相中析出,析出温度为842℃。

关键词： M42高速钢碳化物电渣重熔锻造冶金热力学

茜素红S-铕(Ⅲ)-米诺环素体系的共振瑞利散射光谱研究及应用

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分析科学学报 2010年第4期26卷 431-434页

作者：刘俊轶敖登高娃邢高娃齐岩松内蒙古大学化学化工学院内蒙古呼和浩特010021 内蒙古包头钢铁医院内蒙古包头014010

在pH=4.4的NaAc-HAc缓冲溶液中,茜素红S-铕(Ⅲ)与米诺环素形成三元配合物,导致共振瑞利散射(RRS)增强,据此建立了一种测定米诺环素的RRS分析法。在λ=370nm处,米诺环素浓度在0.073～5.493μg/mL范围内与体系RRS强度呈良好的线性关系,检... 详细信息

在pH=4.4的NaAc-HAc缓冲溶液中,茜素红S-铕(Ⅲ)与米诺环素形成三元配合物,导致共振瑞利散射(RRS)增强,据此建立了一种测定米诺环素的RRS分析法。在λ=370nm处,米诺环素浓度在0.073～5.493μg/mL范围内与体系RRS强度呈良好的线性关系,检出限为0.021μg/mL。该方法灵敏度高,简单、快速,具有良好的选择性和重复性,对尿样进行加标回收及用于片剂、胶囊中米诺环素的测定,结果满意。

关键词：共振瑞利散射米诺环素茜素红S 铕(Ⅲ)

Trivalent Ni oxidation controlled through regulating lithium content to minimize perovskite interfacial recombination

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Rare Metals 2022年第1期41卷 96-105页

作者： Jin-Jin Zhao Xiao Su Zhou Mi ying Zhang Yan-Jun Hu Hua-Jun Guo yi-Nan Jiao Yu-Xia Zhang Yan Shi Wei-Zhong Hao Jing-Wei Wu yi wa.g Cun-Fa Gao Guo-Zhong Cao School of Materials Science and Engineering School of Mechanical EngineeringShijiazhuang Tiedao UniversityShijiazhuang 050043China School of Materials Science and Engineering Hebei Key Laboratory of Material Near Net Forming TechnologyHebei University of Science and TechnologyShijiazhuang 050018China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Materials Science and Engineering University of WashingtonSeattleWA 98195-2120USA

Organic–inorganic hybrid perovskite solar cells,one of the most promising photovoltaic devices,have made great progress in their efficiency and preparation *** this study,uniform,highly conductive Li_(n)NiO_(x)(0≤n≤1;0wa. enhanced through incorporation of the ion pair of Ni^(3+)-Ni^(2+) as the interfacial *** on the amount of lithium doping,controlled interfacial oxidation wa. induced by Ni^(3+).The Li_(0.32)NiO_(x)inhibited charge recombination,reduced the defect density,and enhanced the photocurrent density.A maximum power conversion efficiency of 20.44%wa. obtained by Li_(0.32)NiO_(x).Further,in the long-term,in-air stabilities of unencapsulated Li_(n)-NiO_(x) perovskite solar cells were demonstrated.

关键词： Lithium ions Ni^(3+) Oxidized defect Photocurrent Perovskite solar cells

新型NZSP陶瓷隔膜Ag/AgCl参比电极在低温钠离子熔盐中的稳定性

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中国有色金属学报 2023年第12期33卷 4181-4188页

作者：涂继国常诚冯鑫罗乙娲孟龙焦树强北京科技大学绿色低碳钢铁冶金全国重点实验室北京100083 南方海洋科学与工程广东省实验室海洋工程材料与腐蚀控制创新团队珠海519080 中国科学院过程工程研究所北京100190

开发能长期使用、电位可靠、重现性好的参比电极是熔盐电化学研究的重要基础,针对传统玻璃隔膜Ag/AgCl参比电极在低温熔盐体系中难以实现离子传导及稳定液接电位等问题,本文设计开发了以Na^(+)离子导电陶瓷Na_(3)Zr_(2)Si_(2)PO_(12)(NZ... 详细信息

开发能长期使用、电位可靠、重现性好的参比电极是熔盐电化学研究的重要基础,针对传统玻璃隔膜Ag/AgCl参比电极在低温熔盐体系中难以实现离子传导及稳定液接电位等问题,本文设计开发了以Na^(+)离子导电陶瓷Na_(3)Zr_(2)Si_(2)PO_(12)(NZSP)为隔膜,适用于低温Na^(+)离子熔盐体系的新型Ag/AgCl参比电极;通过电化学测试分析,系统研究了该Ag/AgCl参比电极的稳定性和电位重现性。结果表明:NZSP隔膜能有效阻挡隔膜两端液相之间的互相扩散,Ag/AgCl参比电极的电阻低至300Ω,显示出良好的离子传导能力。多次重复使用后,Ag/AgCl参比电极的电位变化仅±5 mV,显示出优异的电极稳定性和可重复使用特性。总的来说,基于NZSP陶瓷隔膜的新型Ag/AgCl参比电极在低温Na^(+)离子熔盐体系中表现出电位稳定、响应快速及长期使用再现性好等特点。

关键词：低温钠离子熔盐 Ag/AgCl参比电极 NZSP陶瓷离子电导率稳定性

Recent Advances in the Understanding of the Surface Reconstruction of Oxygen Evolution Electrocatalysts and Materials Development

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Electrochemical Energy Reviews 2021年第3期4卷 566-600页

作者： Junwei Chen Haixin Chen Tongwen Yu Ruchun Li yi wa.g Zongping Shao Shuqin Song The Key Lab of Low‑Carbon Chemistry&Energy Conservation of Guangdong Province PCFM LabSchool of Chemical Engineering and TechnologySchool of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275GuangdongChina Jiangsu National Synergetic Innovation Center for Advanced Materials State Key Laboratory of Materials‑Oriented Chemical EngineeringCollege of Chemical EngineeringNanjing Tech UniversityNanjing 210009JiangsuChina wa.School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerthWA 6102Australia

The electrochemical oxygen evolution reaction(OER)plays an important role in many clean electrochemical energy storage and conversion systems,such as electrochemical wa.er splitting,rechargeable metal–air batteries,and electrochemical CO_(2) ***,the OER involves a complex four-electron process and suffers from intrinsically sluggish kinetics,which greatly impairs the efficiency of electrochemical *** addition,state-of-the-art RuO2-based OER electrocatalysts are too expensive and scarce for practical *** development of highly active,cost-effective,and durable electrocatalysts that can improve OER performance(activity and durability)is of significant importance in realizing the widespread application of these advanced *** date,considerable progress has been made in the development of alternative,noble metal-free OER *** these alternative catalysts,transition metal compounds have received particular attention and have shown activities comparable to or even higher than those of their precious metal *** contrast to many other electrocatalysts,such as carbon-based materials,transition metal compounds often exhibit a surface reconstruction phenomenon that is accompanied by the transformation of valence states during electrochemical OER *** surface reconstruction results in changes to the true active sites and an improvement or reduction in OER catalytic ***,understanding the self-reconstruction process and precisely identifying the true active sites on electrocatalyst surfaces will help us to finely tune the properties and activities of OER *** review provides a comprehensive summary of recent progress made in understanding the surface reconstruction phenomena of various transition metal-based OER electrocatalysts,focusing on uncovering the correlations among structure,surface reconstruction and intrinsic *** advances in OER electrocatalysts that

关键词： Oxygen evolution reaction(OER) Surface reconstruction Electrocatalyst Metal oxides In situ/Operando characterization

Defect engineering of high-loading single-atom catalysts for electrochemical carbon dioxide reduction

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Materials Reports(Energy) 2023年第2期3卷 124-141,I0003页

作者： Yang Li Zhenjiang He Feixiang Wu Shuangyin wa.g yi Cheng Sanping Jiang Hunan Provincial Key Laboratory of Nonferrous Value-added Metallurgy Central South UniversityChangsha410083China Engineering Research Center of the Ministry of Education for Advanced Battery Materials Central South UniversityChangsha410083China State Key Laboratory of Chem/Bio-Sensing and Chemometrics Provincial Hunan Key Laboratory for Graphene Materials and DevicesCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha410082China wa.School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerthWA 6102Australia Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen ValleyFoshan528216China

Electrochemical carbon dioxide reduction reaction(CO_(2)RR)provides an attractive approach to carbon capture and utilization for the production high-value-added ***,CO_(2)RR still suffers from poor selectivity and low current density due to its sluggish kinetics and multitudinous reaction ***-atom catalysts(SACs)demonstrate outstanding activity,excellent selectivity,and remarkable atom utilization efficiency,which give impetus to the search for electrocatalytic processes aiming at high *** appears significant activity in the development of efficient SACs for CO_(2)RR,while the density of the atomic sites remains a considerable barrier to be *** construct high-metal-loading SACs,aggregation must be prevented,and thus novel strategies are *** key to creating high-density atomically dispersed sites is designing enough anchoring sites,normally defects,to stabilize the highly mobile separated metal *** this review,we summarized the advances in developing high-loading SACs through defect engineering,with a focus on the synthesis strategies to achieve high atomic site ***,the future opportunities and challenges for CO_(2)RR in the area of high-loading single-atom electrocatalysts are also discussed.

关键词： Single-atom catalysts High loading Electrocatalysis Carbon dioxide reduction(CO_(2)RR) Transition metals

十二指肠非壶腹部病变消化内镜超级微创手术治疗的可行性分析

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中国医师进修杂志 2024年第4期47卷 296-300页

作者：王立辉吕昆明李毅陈倩倩解放军医学院北京100853 解放军总医院第二医学中心消化内科北京100853 解放军总医院第一医学中心消化内科医学部消化内镜超级微创科北京100853

目的探讨十二指肠非壶腹部病变(NADLs)消化内镜超级微创手术(SMIS)治疗的可行性,为临床治疗及后续研究提供参考。方法回顾性分析2004年9月至2023年9月在解放军总医院第一医学中心行消化内镜SMIS治疗的206例NADLs患者,按治疗方法分为内... 详细信息

目的探讨十二指肠非壶腹部病变(NADLs)消化内镜超级微创手术(SMIS)治疗的可行性,为临床治疗及后续研究提供参考。方法回顾性分析2004年9月至2023年9月在解放军总医院第一医学中心行消化内镜SMIS治疗的206例NADLs患者,按治疗方法分为内镜息肉高频电切除术组(21例)、内镜黏膜切除术(EMR)组(67例)、预切开内镜黏膜切除术(Pre-cut-EMR)组(20例)、内镜黏膜下剥离术(ESD)组(97例)和内镜全层切除术(EFR)组(1例)。收集患者的术前、术中及术后情况并比较组间差异。结果ESD治疗患者比与非ESD治疗患者的牵引辅助率更高。术中穿孔发生率为3.40%(7/206),术后并发情况发生率为6.31%(13/206)。在术后并发情况方面,ESD治疗患者高于非ESD治疗患者[10.31%(10/97)比2.75%(3/109),P=0.026],降部病变患者高于非降部病变患者[11.71%(13/111)比0,P=0.001],牵引辅助内镜黏膜下剥离术患者均无术后并发情况。与无术后并发情况患者相比,有术后并发情况患者内镜下息肉长径更长[(2.36±1.36)cm比(1.62±0.93)cm,P=0.015],留置胃管率更高[8/13比27.46%(53/193),P=0.022],留置胃管天数更长[(9.25±2.96)d比(3.95±1.76)d,P<0.001],质子泵抑制剂(PPI)泵入天数更长[(9.69±3.68)d比(4.88±2.47)d,P<0.001],恢复饮食更晚[(8.17±2.82)d比(3.98±1.93)d,P<0.001],住院天数更长[(14.23±5.00)d比(6.64±2.49)d,P<0.001],一级护理天数更长[(9.23±3.77)d比(4.26±2.58)d,P<0.001]。结论针对不同NADLs情况选择合适的消化内镜SMIS治疗方式和加强术后重点处理有助于减少并发症的发生,NADLs消化内镜SMIS治疗具有可行性。

关键词：十二指肠疾病内窥镜黏膜切除术手术中并发症手术后并发症手术后医护

Real-time hyperspectral imaging for the in-field estimation of strawberry ripeness with deep learning

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Artificial Intelligence in Agriculture 2020年第1期4卷 31-38页

作者： Zongmei Gao Yuanyuan Shao Guantao Xuan Yongxian wa.g yi Liu Xiang Han Center for Precision and Automated Agricultural Systems Department of Biological Systems EngineeringWashington State UniversityProsserWA 99350USA College of Mechanical and Electrical Engineering Shandong Agricultural UniversityTai'an 271018China Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China College of Agriculture Food and Natural ResourcesUniversity of MissouriColumbiaMO 65211USA

Strawberry is one of the popular fruits with numerous *** ripeness of this fruits wa. estimated using the hyperspectral imaging(HSI)system in field and laboratory conditions in this *** at early ripe and ripe stageswere collected HSI data,coveredwa.elength ranges from370 to 1015 *** featurewa.elengths were selected using the sequential feature selection(SFS)*** wa.elengths selected for field(530 and 604 nm)and laboratory(528 and 715 nm)samples,***,reliability of such spectral featureswa. validated based on support vectormachine(SVM)*** of SVMclassification models had good resultswith receiver operating characteristic values for samples under both field and laboratory conditions higher than ***,the spatial feature images were extracted from the spectral feature wa.elength and the first three principal components for laboratory *** AlexNet convolutional neural network(CNN)wa. used to classify the early ripe and ripe strawberry samples,which obtained the accuracy of 98.6%for test *** above results indicated real-time HSI system wa. promising for estimating strawberry ripeness under field and laboratory conditions,which could be a potential application technique for evaluating the harvesting time management for farmers and producers.

关键词： Strawberry ripeness Hyperspectral imagery In field CNN

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创伤后应激障碍发生自杀的研究进展

神经疾病与精神卫生 2016年第2期16卷 197-201页

作者：王岚王学义河北医科大学第一医院精神科 050031 河北医科大学精神卫生研究所河北省脑老化与认知神经科学实验室

随着近年来对创伤后应激障碍（PTSD）的关注越来越多，目前认为PTSD患者自杀率远远高于普通人群，因此，早期识别自杀并干预将具有重大的医学和社会意义。现从PTSD发生自杀的流行病学、影响因素、生物学机制及干预几个方面进行综述。

关键词：创伤后应激障碍自杀综述文献