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内镜套扎术联合生长抑素治疗肝硬化食管静脉曲张出血患者的效果

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中外医学研究 2024年第19期22卷 104-108页

作者：武少林贵航贵阳医院贵州贵阳550009

目的:探析内镜套扎术联合生长抑素治疗肝硬化食管静脉曲张出血患者的效果。方法:择取2020年1月—2023年9月贵航贵阳医院收治的72例肝硬化食管静脉曲张出血患者作为研究对象,随机分对照组和观察组,各36例。对照组给予内镜套扎术治疗,观... 详细信息

目的:探析内镜套扎术联合生长抑素治疗肝硬化食管静脉曲张出血患者的效果。方法:择取2020年1月—2023年9月贵航贵阳医院收治的72例肝硬化食管静脉曲张出血患者作为研究对象,随机分对照组和观察组,各36例。对照组给予内镜套扎术治疗,观察组在对照组基础上联合生长抑素治疗;比较两组临床指标(止血时间、输血总量及住院时间)、血流动力学指标(门静脉及脾静脉血流量)、并发症发生率及消化道再出血情况。结果:观察组总有效率高于对照组,差异有统计学意义(P0.05);观察组再出血率低于对照组,差异有统计学意义(P<0.05)。结论:内镜套扎术联合生长抑素治疗肝硬化食管静脉曲张出血患者效果显著,止血效果突出,有助于促进患者术后康复,降低术后再出血风险。

关键词：内镜套扎术生长抑素肝硬化食管静脉曲张出血并发症

基于导电油墨层电阻层析成像的混凝土裂缝损伤识别

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传感技术学报 2024年第6期37卷 1084-1089页

作者：蔡晨宁陈少林刘丽娜南京航空航天大学民航学院江苏南京211106 南京航空航天大学金城学院江苏南京211156

为解决混凝土裂缝损伤的监测问题,提出利用石墨烯碳油墨在混凝土表面制备导电层,利用电阻层析成像技术进行裂缝损伤识别。通过比较损伤前后导电层边界电压变化,利用TV-SB正则化算法重建损伤引起的电导率变化分布图像以确定裂缝损伤情况... 详细信息

为解决混凝土裂缝损伤的监测问题,提出利用石墨烯碳油墨在混凝土表面制备导电层,利用电阻层析成像技术进行裂缝损伤识别。通过比较损伤前后导电层边界电压变化,利用TV-SB正则化算法重建损伤引起的电导率变化分布图像以确定裂缝损伤情况。分别进行人工模拟裂缝和混凝土梁弯曲裂缝检测实验,来验证所提方法对裂缝损伤识别的效果。实验结果表明,导电油墨层性能良好,电阻层析成像技术重建的电导率变化图像能够较好地反映裂缝损伤的位置和长度等信息,可为混凝土裂缝损伤的监测和识别提供一种有前景的技术。

关键词：混凝土结构监测电阻层析成像裂缝损伤识别导电油墨层

Tribological properties of copper matrix composites reinforced with homogeneously dispersed graphene nanosheets

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Journal of Materials Science & Technology 2018年第10期34卷 1925-1931页

作者： Xin Gao Hongyan Yue Erjun Guo shaolin zhang Longhui Yao Xuanyu Lin Bao wang Enhao Guan School of Materials Science and Engineering Harbin University of Science and Technology Department of Physics Dongguk University

Graphene reinforced copper matrix composites （Gr/Cu） were fabricated by electrostatic self-assembly and powder metallurgy. The morphology and structure of graphene oxide, graphene oxide-Cu powders and Gr/Cu composites were characterized by scanning electronic microscopy, transmission electronic microscopy, X-ray diffraction and Raman spectroscopy, respectively. The effects of graphene contents, applied loads and sliding speeds on the tribological behavior of the composites were investigated. The results indicate that the coefficient of friction of the composites decreases first and then increases with increasing the graphene content. The lowest friction coefficient is achieved in 0.3 wt~ Gr/Cu composite, which decreases by 65% compared to that of pure copper. The coefficient of friction of the composite does not have significant change with increasing the applied load, however, it increases with increasing the sliding speed. The tribological mechanisms of the composite under different conditions were also investigated.

关键词： Graphene nanosheets Copper matrix composites Tribological properties Microstructure

Facile Synthesis of Chiral α-Hydroxy Ketones by a Ni-Catalyzed Multicomponent Hydrometallation–CO Insertion–Enantioconvergent Alkylation Cascade

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Chinese Journal of Chemistry 2023年第3期41卷 294-300页

作者： Jian Chen Gao Deng You wang shaolin Zhu State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210093 China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan453007 China

NiH-catalyzed multicomponent reductive hydrofunctionalization of alkenes is an attractive but poorly explored approach to rapidly increasing molecular *** this process,the selective generation of the desired product can be ***,we report that a highly chemo-,regio-and enantioselective reductive hydrocarbonylation of alkenes has been achieved using a chloroformate ester as a source of CO.A wide range of structurally diverseα-hydroxy ketones,privileged structural elements in bioactive molecules and useful building blocks,were obtained from such reactions with high enantiomeric purity.

关键词： Alkenes Asymmetric catalysis Hydrofunctionalization Multicomponent reactions Nickel Nickel hydride Synthetic methods Hydrocarbonylation

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中板冷却U型或龟背的产生机制

金属功能材料 2024年第3期31卷 59-66页

作者：张鹤雄吴浩鸿汪宏兵肖少林刘宁湖南华菱涟源钢铁有限公司湖南娄底417000

基于4种组分钢种的工业生产数据分析,借助金相分析和模拟计算的手段,阐明了中板冷却U型和龟背的产生机制。U型的产生由上下表面热胀冷缩的差异主导,此时钢板上表面冷速大于下表面,导致上表面冷却收缩大于下表面,呈现冷却U型;龟背的产生... 详细信息

基于4种组分钢种的工业生产数据分析,借助金相分析和模拟计算的手段,阐明了中板冷却U型和龟背的产生机制。U型的产生由上下表面热胀冷缩的差异主导,此时钢板上表面冷速大于下表面,导致上表面冷却收缩大于下表面,呈现冷却U型;龟背的产生由上下表面相变膨胀的差异主导,此时钢板上表面显著的相变膨胀导致其呈现冷却龟背。提出了增大下表面冷却水量的控制措施,工业生产证明该措施可显著改善中板冷却板形。

关键词：中板 U型龟背热膨胀相变膨胀

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基于单镜头无人机的胜天水库大坝测绘

水利水电快报 2024年第1期45卷 23-27,38页

作者：潘绍林毕节市勘测设计研究院贵州毕节551700

为获取多视角影像,保证实景三维模型的建模质量,以胜天水库项目区域测绘为例,通过摄影测量2D、井字飞行、五向飞行3种航线构建实景三维模型,并进行三维模型精度比较;采用CASS_3D平台进行1∶500地形图立体测绘,并与网络RTK地形图测绘成... 详细信息

为获取多视角影像,保证实景三维模型的建模质量,以胜天水库项目区域测绘为例,通过摄影测量2D、井字飞行、五向飞行3种航线构建实景三维模型,并进行三维模型精度比较;采用CASS_3D平台进行1∶500地形图立体测绘,并与网络RTK地形图测绘成果进行对比分析。结果表明:3种航线建模方法测绘的地形图均达到1∶500地形图精度要求;其中,通过五向飞行航线获取影像资料建立的实景三维模型取得的平面地物信息误差最小、精度最好。研究成果可为中小型测绘生产单位使用单镜头无人机在山区地形起伏较大、作业难度较高的区域开展水库大坝测绘提供参考。

关键词：单镜头无人机三维建模地形图测绘胜天水库

彩色多普勒超声辅助下超薄胸背动脉穿支皮瓣的切取方案及临床应用效果

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中华烧伤与创面修复杂志 2024年第3期40卷 281-288页

作者：赵书明刘娜刘学亮冀少林华北医疗健康集团邢台总医院骨三科邢台054000 华北医疗健康集团邢台总医院医务部邢台054000 山东大学附属山东省立第三医院创伤与手足外科济南250031

目的探讨彩色多普勒超声辅助下超薄胸背动脉穿支皮瓣的切取方案及临床应用效果。方法该研究为回顾性历史对照研究。将2017年2月—2019年10月华北医疗健康集团邢台总医院骨三科(以下简称本科室)收治的20例符合入选标准且采用根据术者临... 详细信息

目的探讨彩色多普勒超声辅助下超薄胸背动脉穿支皮瓣的切取方案及临床应用效果。方法该研究为回顾性历史对照研究。将2017年2月—2019年10月华北医疗健康集团邢台总医院骨三科(以下简称本科室)收治的20例符合入选标准且采用根据术者临床经验设计、切取的超薄胸背动脉穿支皮瓣修复四肢皮肤软组织缺损的患者作为对照组,其中男16例、女4例,年龄(37±5)岁;将2019年11月—2022年12月本科室收治的21例符合入选标准且采用在彩色多普勒超声辅助下设计、切取的超薄胸背动脉穿支皮瓣修复四肢皮肤软组织缺损的患者作为超声辅助组,其中男15例、女6例,年龄(38±6)岁。清创后,四肢皮肤软组织缺损范围5.0 cm×4.0 cm~19.0 cm×8.0 cm,胸背动脉穿支皮瓣面积为6.0 cm×5.0 cm~20.0 cm×9.0 cm。将供瓣区创面直接拉拢缝合。统计超声辅助组患者彩色多普勒超声检查耗时、费用,比较术前彩色多普勒超声探查到的胸背动脉穿支血管数量、类型、位置和术中实际探查情况是否一致。记录2组患者皮瓣完整切取耗时。术后1、3、5、7、14 d,采用皮瓣血运评估量表评估2组患者皮瓣血运情况。术后14 d,观察2组患者皮瓣成活情况并计算皮瓣成活面积百分比。术后6个月,采用利克特5级量表评估2组患者对治疗效果的满意度并计算满意率。结果超声辅助组患者术前彩色多普勒超声检查耗时为(10.5±2.3)min、费用为120元;术前通过彩色多普勒超声探查并标记出21条胸背动脉穿支血管,其中8条(38.10%)1型穿支血管,10条(47.62%)2型穿支血管和3条(14.29%)3型穿支血管,术前探查到的胸背动脉穿支血管数量、类型、位置与术中探查情况一致。超声辅助组患者皮瓣完整切取耗时(41±10)min,明显短于对照组的(63±12)min(t=6.32,P0.05)。结论术前行彩色多普勒超声探测穿支血管的数量、类型及位置等的准确率高;根据不同穿支血管类型设计超薄胸背动脉穿支皮瓣切取方案,能缩短手术时间,提高皮瓣的成活率。

关键词：创伤和损伤超声检查,多普勒,彩色穿支皮瓣超薄皮瓣创面修复

LSTM based prediction algorithm and abnormal change detection for temperature in aerospace gyroscope shell

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International Journal of Intelligent Computing and Cybernetics 2019年第2期12卷 274-291页

作者： Haoqiang Shi shaolin Hu Jiaxu zhang School of Automation and Information Engineering Xi’an University of TechnologyXi’anChina Automation School Guangdong University of Petrochemical TechnologyMaomingChina

Purpose–Abnormal changes in temperature directly affect the stability and reliability of a *** the temperature and detecting the abnormal change is great value for timely understanding of the working state of the *** that the actual collected gyroscope shell temperature data have strong non-linearity and are accompanied by random noise pollution,the prediction accuracy and convergence speed of the traditional method need to be *** purpose of this paper is to use a predictive model with strong nonlinear mapping ability to predict the temperature of the gyroscope to improve the prediction accuracy and detect the abnormal ***/methodology/approach–In this paper,an double hiddenlayer long-shortterm memory(LSTM)is presentedto predicttemperature data for the gyroscope(including singlepoint andperiod prediction),and the evaluation index of the prediction effect is also proposed,and the prediction effects of shell temperature data are compared by BP network,support vector machine(SVM)and LSTM *** the estimated value detects the abnormal change of the ***–By combined simulation calculation with the gyroscope measured data,the effect of different network hyperparameters on shell temperature prediction of the gyroscope is analyzed,and the LSTM networkcan beusedto predictthe temperature(timeseriesdata).Bycomparingthe performance indicatorsof different prediction methods,the accuracy of the shell temperature estimation by LSTM is better,which can meet the requirements of abnormal change *** and accurate diagnosis of different types of gyroscopefaults(stepsanddrifts)can ***–The LSTMmodelisa deepneuralnetworkmodelwithmultiplenon-linearmapping levels,and can abstract the input signal layer by layer and extract features to discover deeper underlying *** improved method has been used to solve the problem of strong

关键词： Gyroscope LSTM Temperature prediction Recurrent neural network Abnormal change detection

Spatial Effect of Mineral Resources Exploitation on Urbanization:A Case Study of Tarim River Basin,Xinjiang,China

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Chinese Geographical Science 2012年第5期22卷 590-601页

作者： LI Xuemei zhang Xiaolei DU Hongru CHU shaolin Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Academy of Economy Research of Xinjiang Development and ReJbrm Commission Urumqi 830002 China Grassland Research Institute of Animal Science Academy of Xinjiang Uygur Autonomous Region Urumqi 830000 China

Mineral resources exploitation significantly affects the spatial structure and evolutive trend of urbanization in arid *** this study,the spatial autocorrelation method and the spatial computation model were used to investigate the spatial impacts of mineral resources excavation and processing on comprehensive level of urbanization in the Tarim River Basin,Xinjiang,China for the years of 2000,2006 and *** results are as follows:1)There was a spatial correlation of the development of mineral resources industry and the comprehensive level of urbanization in 2006 and 2008,with the spatial concentration trend rising significantly in 2006 and decreasing in 2008.2)The patterns of local spatial concentration of mineral resources industry and of the comprehensive level of urbanization were relatively stable,and the two patterns showed signs of spatial *** higher was the degree of the concentration of mineral resources industry,the stronger was its impact on the spatial clustering of urbanization.3)In 2000, mineral resources excavation and processing had a significant positive impact on the comprehensive level of urbanization in the region but not in its adjacent ***,in 2008,mineral resources excavation and processing significantly raised the comprehensive level of urbanization not only in the region but also in its neighboring *** research demonstrates that the development of mineral resources industry can strongly affect the trends and spatial patterns of urbanization.

关键词： mineral resources development urbanization spatial effect Tarim River Basin