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Characteristics and stability of oxide+carbonitride in H13 steel at 1250℃

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Journal of Iron and Steel Research International 2024年第1期31卷 134-142页

作者： Xiao-lin Sun Han-jie guo jing guo Fei Wang Dong Xu Gao-yang Song Shuai Wang School of Materials Science and Engineering Hebei University of EngineeringHandan056038HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China High Temperature Materials Research Institute Central Iron and Steel Research Institute Co.Ltd.Beijing100081China Technology Innovation Center for High Quality Cold Heading Steel of Hebei Province Hebei University of EngineeringHandan056038HebeiChina

The morphology,size,quantity,and composition of complex oxide+carbonitride in H13 steel held at 1250℃for 5,10,and 15 h were *** results show that the ratio and number of complex carbonitrides with cores in H13 steel are gradually increased when holding at 1250℃compared with those in the original H13 steel,and the core size *** are one or more oxide cores in(Ti_(x),V_(1-x))(Cy,N_(1-y)),including xCaO·zAl_(2)O_(3),xCaO·yMgO·zAl_(2)O_(3),and CaO after holding at 1250℃,in addition to MgO·Al_(2)O_(3)and Al_(2)O_(3)in the original *** equilibrium temperature for(Ti_(x),V_(1-x))(Cy,N_(1-y))precipitation at the solidification front and decomposition in the solid state was theoretically analyzed,which was affected by the x value and the product of Ti and N contents in H13 ***,the composition of(Ti_(x),V_(1-x))(Cy,N_(1-y))is influenced by the oxide *** is convinced that(Ti_(x),V_(1-x))(Cy,N_(1-y))with oxide cores has a higher stability,especially for oxides with a high Al_(2)O_(3)*** treatment at high temperature facilitates a more reasonable analysis of oxide+carbonitride,and the generation mechanism of oxide+carbonitride was discussed.

关键词： Complex carbonitride Decomposition Oxide core Characteristic Stability

Reduction behavior of iron ore powder by high-volatile coal in thermogravimetric-gas chromatographic and kinetic analysis

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Journal of Iron and Steel Research International 2024年第1期31卷 92-107页

作者： Rui-meng Shi Qi-yuan Mi Bin Li Xiao Shi Chong Zou jing guo Han-jie guo School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina China International Engineering Consulting Corporation Beijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The reduction behavior of iron ore powder by high-volatile coal was investigated,and its kinetic mechanism was *** effect of volatiles in coal on the reduction reaction of iron ore was compared by utilizing a Xinjiang lignite with a high volatile content and its pyrolysis carbon produced by high-temperature pyrolysis to remove volatiles,serving as a *** mass loss and gas composition of the samples during the reduction process were detected using thermo-gravimetric analysis and gas chromatography,and the morphological changes of iron ore powder were observed through scanning electron *** kinetic parameters of the iron oxide reduction reaction were calculated by the Flynn-Ozawa-Wall method,and the kinetic mechanism of volatile participation in the iron oxide reduction reaction was determined through the Coats-Redfern *** results indicate that the coupling effect between the high-volatile coal pyrolysis and reduction reactions occurs during the second stage of the entire coupling process,which corresponds to the late stage of coal pyrolysis with a substantial release of H_(2)and *** volatiles in coal actively participated in the reduction reaction,reducing the initiation temperature of the reaction by around 200℃.The reduction of iron oxides by high-volatile coal was jointly promoted by the"hydrogen cycle"and"carbon cycle",resulting in a higher reduction extent and metallization rate at the end of the *** high-volatile coal was used as the reductant,the average activation energy for the entire process was 76.5 kJ/mol,a significant decrease compared to the employment of pyrolysis carbon without volatiles as the reductant(1167 kJ/mol).

关键词： Direct reduction High-volatile coal Volatile Kinetics Reduction mechanism

弥散张量成像诊断弥漫性轴索损伤的敏感性及意识状态的研究

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中华神经医学杂志 2013年第9期12卷 944-946页

作者：刘克君荆国杰姚晓腾景英朝李毅毅李王安谢乙团赵冬青李百升惠州市第一人民医院神经外科惠州市神经外科研究所516001 惠州市中心人民医院神经外科 516000

目的研究弥散张量成像（DTI）诊断弥漫性轴索损伤（DAI）的敏感性，及探讨中脑区各向异性分数（FA）值与GCS评分的相关性以定量评估DAI的损伤程度。方法选择惠州市第一人民医院及惠州市中心人民医院神经外科自2007年1月至2013年1月临床... 详细信息

目的研究弥散张量成像（DTI）诊断弥漫性轴索损伤（DAI）的敏感性，及探讨中脑区各向异性分数（FA）值与GCS评分的相关性以定量评估DAI的损伤程度。方法选择惠州市第一人民医院及惠州市中心人民医院神经外科自2007年1月至2013年1月临床诊断为DAI的105例患者为研究对象，对其在入院时行CT、MRJ平扫及DTI扫描，观察比较3种不同影像学方法检测DAI损伤病灶的敏感性差异，并分析其中36例DAI患者中脑区FA值与人院时GCS评分的相关性。结果CT检测DAI损伤病灶的敏感性为70．48％，MR／平扫为82．86％，DTI为95．24％．3者比较差异具有统计学意义（P〈0．051，其中以DTI检查诊断的敏感性为最高。患者人院时GCS评分与中脑区FA值存在正相关关系（r=0．977，P=0．000）。结论DTI不仅在诊断DAI敏感性方面优于CT和MRI平扫，且在一定程度上可客观地评估DAI的损伤程度。

关键词：弥漫性轴索损伤弥散张量成像敏感性各向异性分数格拉斯哥昏迷评分

Investigation of the kinetic mechanism of the demanganization reaction between carbon-saturated liquid iron and CaF2–CaO–SiO2-based slags

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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 399-404页

作者： Sheng-chao Duan Chuang Li Han-jie guo jing guo Shao-wei Han Wen-sheng Yang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing 100083 China China Metallurgical Planning and Research Institute Beijing 100711 China

The demanganization reaction kinetics of carbon-saturated liquid iron with an eight-component slag consisting of CaO–SiO2–MgO–FeO–MnO–Al2O3–TiO2–CaF2 was investigated at 1553, 1623, and 1673 K in this study. The rate-controlling step（RCS） for the demanganization reaction with regard to the hot metal pretreatment conditions was studied via kinetics analysis based on the fundamental equation of heterogeneous reaction kinetics. From the temperature dependence of the mass transfer coefficient of a transition-metal oxide（MnO）, the apparent activation energy of the demanganization reaction was estimated to be 189.46 kJ·mol^–1 in the current study, which indicated that the mass transfer of MnO in the molten slag controlled the overall rate of the demanganization reaction. The calculated apparent activation energy was slightly lower than the values reported in the literature for mass transfer in a slag phase. This difference was attributed to an increase in the ＂specific reaction interface＂（SRI） value, either as a result of turbulence at the reaction interface or a decrease of the absolute amount of slag phase during sampling, and to the addition of calcium fluoride to the slag.

关键词： demoaganization reaction kinetics reaction mechanism kinetic model rate-controlling step mass transfer coefficient apparent activation energy

基于中国生物医学文献数据库的ICU谵妄护理文献计量学分析

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护理管理杂志 2017年第7期17卷 475-478页

作者：井杰郭海凌孙建华夏光辉中国医学科学院北京协和医学院北京协和医院重症医学科北京市100730 中国医学科学院医学信息研究所医学知识组织研究室北京市100020

目的探讨近十年国内ICU谵妄护理的研究趋势和研究热点,为ICU谵妄护理研究的发展方向提供参考和借鉴。方法通过检索中国生物医学文献数据库收录的2006~2015年间国内发表的ICU谵妄护理研究论文,采用Thomson Data Analyzer(TDA)分析软件提... 详细信息

目的探讨近十年国内ICU谵妄护理的研究趋势和研究热点,为ICU谵妄护理研究的发展方向提供参考和借鉴。方法通过检索中国生物医学文献数据库收录的2006~2015年间国内发表的ICU谵妄护理研究论文,采用Thomson Data Analyzer(TDA)分析软件提取数据,从年代变化、地区分布、机构类型、机构发文、作者发文、期刊分布、基金资助、关键词、主题词等方面进行计量学分析。结果遴选出ICU谵妄护理文献311篇,年文献发表量进入快速增长阶段;机构合作率为12.86%,篇均作者数为2.69,基金论文比为0.09。结论我国ICU谵妄护理研究已经受到广泛关注和重视,但是领域内研究机构之间的合作率偏低,科研基金资助论文比例不高,后续研究应注重获取科研基金资助并加强合作。

关键词： ICU谵妄 ICU综合征护理中国生物医学文献数据库

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急诊绿色通道在颅脑创伤患者中的应用效果

实用心脑肺血管病杂志 2017年第B12期25卷 68-69页

作者：林才姚晓腾李王安荆国杰曾春生广东省惠州市第一人民医院神经外科 516000

目的分析急诊绿色通道在颅脑创伤患者中的应用效果。方法选取惠州市第一人民医院2013—2014年收治的颅脑创伤患者58例作为对照组,2015—2016年收治的颅脑创伤患者66例作为观察组。对照组患者行常规急诊救治,观察组患者行急诊绿色通道救... 详细信息

目的分析急诊绿色通道在颅脑创伤患者中的应用效果。方法选取惠州市第一人民医院2013—2014年收治的颅脑创伤患者58例作为对照组,2015—2016年收治的颅脑创伤患者66例作为观察组。对照组患者行常规急诊救治,观察组患者行急诊绿色通道救治。比较两组患者来院至检查完成时间,来院至手术开始时间,住院时间,术前、术后2周格拉斯哥昏迷量表(GCS)评分及Barthel指数评分。结果观察组患者来院至检查完成时间、来院至手术开始时间、住院时间短于对照组(P0.05);术后2周观察组患者GCS评分、Barthel指数评分高于对照组(P<0.05)。结论急诊绿色通道在颅脑创伤患者中的应用效果良好,有利于缩短急诊救治时间及住院时间,改善患者生存质量及预后。

关键词：颅脑损伤急救医疗服务急诊处理

Improvement of increased cQTd is associated with heart function in patients with ischemic heart failure

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Journal of Geriatric Cardiology 2018年第1期15卷 41-49页

作者： Hui guo Miao WANG Juan ZHAO jing LIU jie-Mei YANG Department of Cardiology the First Affiliated Hospital of Harbin Medical University Harbin China Department of Cardiology Ultrasound the First Affiliated Hospital of Harbin Medical University Harbin China

Background Chronic heart failure （CHF） is life-threatening without timely or effective intervention. In this study, we investigated the association between QT dispersion corrected for heart rate （cQTd） and heart function in patients with CHF. Methods From January 2013 to December 2015, we continuously enrolled 240 patients categorized as New York Heart Association functional class （NYHA） III-IV with a left ventricular ejection fraction （LVEF）〈 40%. Based on the etiology, the patients were divided into a dilated cardiomyopathy （DCM） group （n = 120） and an ischemic cardiomyopathy （ICM） group （n = 120）. Then, based on the cQTd width, the ICM group was divided into two subgroups： a QS group （cQTd ≤60 ms, n = 70） and a QL group （cQTd 〉 60 ms, n = 50）. All patients were examined by echocardiography and 12-lead electrocardiography （ECG） at 1, 3, 6, and 12 months after enrollment. Results After one year of optimized medical treatment, patients in both groups showed significant improvement in LVEF and NYHA classification from baseline. However, the cQTd in the ICM group, especially the QL, was significantly shorter than that in the DCM group at each time point. In addition, the cQTd was negatively correlated with LVEF and 6-min walking test and positively correlated with NYHA class in the ICM group. Conclusions The present findings clearly demonstrate that cQTd is a meaningful parameter for assessing heart function in the follow-up of ICM patients.

关键词： Cardiac dyssynchrony Chronic heart failure Corrected QT dispersion Heart function Ischemic cardiomyopathy

Effect of ultrasonic micro-forging treatment on microstructure and mechanical properties of GH3039 superalloy processed by directed energy deposition

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Journal of Materials Science & Technology 2021年第11期70卷 185-196页

作者： Qingqing Li Yong Zhang jie Chen Bugao guo Weicheng Wang Yuhai jing Yong Liu Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province Nanchang UniversityNanchang 330031China Postdoctoral Research Station of Mechanical Engineering Nanchang UniversityNanchang 330031China

In this work,ultrasonic micro-forging treatment(UMFT)was introduced to achieve homogeneous microstructure,reduce defects and improve mechanical properties of GH3039 superalloy cladding layer processed by directed energy deposition(DED).The microstructure,defects and mechanical properties of the cladding layers treated by UMFT with different ultrasonic powers(UIPs)were *** revealed a gradient structure as equiaxed grains distributed at the top,a columnar-to-equiaxed transition(CET)region that mixed of columnar dendrites and equiaxed grains distributed at the middle and columnar dendrites at the bottom of the cladding layer was *** UMFT,the proportion of equiaxed grains was increased,the average size of equiaxed grains was refined to 10μm from 16μm,the orientation of grains was more uniform and the phases enriched of Al,Ti,C,Nb and Mo were *** grain refinement can be attributed to the fracture of columnar dendrites induced by the ultrasonic vibration during ***,the porosity of the cladding layer was reduced after *** microhardness of the cladding layers exhibited a depth-dependent gradient at the top *** microhardness of the top surface was the highest and showed an increasing trend with the increase of *** microhardness of different grain morphologies exhibited no substantial ***,due to grain refinement and precipitation of strengthening phase induced by UMFT,the microhadness of some local locations were *** results indicated UMFT has a significant effect on improving the microstructure,defects and mechanical properties of the deposited cladding layer.

关键词： Directed energy deposition GH3039 superalloy Ultrasonic micro-forging treatment Microstructure evolution Mechanical properties

Tailoring polymer acceptors by electron linkers for achieving efficient and stable all-polymer solar cells

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National Science Review 2022年第2期9卷 88-98页

作者： Qiang Wu Wei Wang Yao Wu Rui Sun jing guo Mumin Shi jie Min The Institute for Advanced Studies Wuhan University Key Laboratory of Materials Processing and Mold (Zhengzhou University) Ministry of Education Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of Technology

The trade-off between efficiency and stability is a bit vague,and it can be tricky to precisely control the bulk morphology to simultaneously improve device efficiency and ***,three fused-ring conducted polymer acceptors containing fur an,thiophene and selenophene as the electron linkers in their conjugated backbones,namely PY-O,PY-S and PY-S e,were designed and *** electron linker engineering affects the intermolecular interactions of relative polymer acceptors and their charge transport ***,excellent material compatibility was achieved when PY-Se was blended with polymer donor PBDB-T,resulting in nanoscale domains with favorable phase *** optimized PBDB-T:PY-Se blend not only exhibits maximum performance with a power conversion efficiency of 15.48%,which is much higher than those of PBDB-T:PY-O(9.80%) and PBDB-T:PY-S(14.16%) devices,but also shows better storage and operational stabilities,and mechanical *** work demonstrates that precise modification of electron linkers can be a practical way to simultaneously actualize molecular crystallinity and phase mis cibility for improving the performance of all-polymer solar cells,showing practical significance.

关键词： all-polymer solar cells polymer acceptors electron linker intermolecular interaction molecular compatibility stability