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Copper Fiber Reinforced Alkali-activated Slag Composite Friction Materials by Hot-pressing Method
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作者 ZHAO Zhe XU Lixin +3 位作者 YANG Jiale SI Jiahui ZHU Song JIANG Changjun 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期381-390,共10页
As the speeds of trains increase,higher demands are placed on brake materials.In order to overcome the thermal degradation phenomenon of brake pads during high-speed braking,we prepared copper fiber reinforced alkali-... As the speeds of trains increase,higher demands are placed on brake materials.In order to overcome the thermal degradation phenomenon of brake pads during high-speed braking,we prepared copper fiber reinforced alkali-activated slag composite(AASC)friction materials by hot-pressing method,using slag as matrix,Na_(2)SiO_(3)·9H_(2)O as alkali excitant,copper fiber as reinforcement,and graphite as friction modifier.The results show that the AASC prepared by hot-pressing method has undergone alkali-activated reaction and has geopolymer amorphous characteristics as the conventional cast molding AASC by XRD analysis.The addition of copper fibers can improve the mechanical strength and toughness of the composites substantially,and the AASC has the highest flexural strength,compressive strength and impact toughness when the volume fraction of copper fibers reaches 25 vol%.Toughening mechanisms such as drawing,bridging and crack deflection of copper fibers in composites were analyzed by SEM morphology.Addition of appropriate amount of graphite to AASC can effectively reduce the wear rate and improve the stability of the material friction coefficient.The coefficient of friction also remains stable in the high-speed friction experiments without thermal degradation.Therefore,copper fiber reinforced AASC friction materials prepared by hot-pressing method has good mechanical and friction properties. 展开更多
关键词 hot-pressING alkali-activated slag copper fiber mechanical properties tribological performance
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Interfacial reaction process of the hot-pressed WC/2024Al composite 被引量:10
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作者 Chang-Hui Mao Xu-Dong Sun +2 位作者 Qiu-Shi Liang Jian Yang Jun Du 《Rare Metals》 SCIE EI CAS CSCD 2013年第4期397-401,共5页
12 vol%WCp/2024Al composite was fabricated from mixed powders by hot-pressing at various tempera-tures. Investigation of the interfacial reaction between the WC phase and the Al alloy matrix was performed by X-ray dif... 12 vol%WCp/2024Al composite was fabricated from mixed powders by hot-pressing at various tempera-tures. Investigation of the interfacial reaction between the WC phase and the Al alloy matrix was performed by X-ray diffraction (XRD), transmission electron microscope (TEM) and energy dispersive spectroscopy (EDS). A multiple layer interface structure, which is composed of Al/ WAl12/AlnC3/WC, is found to form by the interfacial reaction during hot-pressing. Further study shows that the AlaC3 layer forms along with a given crystal orientation of WC phase and might retard the interfacial reaction process. 展开更多
关键词 Metal-matrix composites (MMCs) Interfacialreaction hot-pressING
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SYNTHESIS, CHARACTERIZATION AND ION TRANSPORT PROPERTIES OF HOT-PRESSED SOLID POLYMER ELECTROLYTES (1-x) PEO:x KI 被引量:4
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作者 Angesh Chandra Archana Chandra K. Thakur 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第2期302-308,共7页
Synthesis and ion transport properties of hot-pressed solid polymer electrolytes (SPEs), (l-x) PEO: x KI, where x is the content of KI in wt%, are reported. A hot-press technique has been used for the formation o... Synthesis and ion transport properties of hot-pressed solid polymer electrolytes (SPEs), (l-x) PEO: x KI, where x is the content of KI in wt%, are reported. A hot-press technique has been used for the formation of the polymeric membranes in place of the usual solution cast method. The composition (80 PEO:20 KI) was identified as the highest conducting polymer electrolyte on the basis of compositional dependent conductivity studies of PEO:KI films. A conductivity enhancement of more than two orders of magnitude from that of the pure PEO was achieved. Materials characterization and ion transport mechanism were explained by using various experimental techniques. 展开更多
关键词 Solid polymer electrolyte hot-press technique Ionic conductivity Ionic mobility XRD Polymeric battery.
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Properties of Hot-Pressed Al_2O_3-Fe Composites 被引量:4
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作者 M.M.El-Sayed Seleman, Xudong SUN and Liang ZUO Department of Materials Science and Engineering, Northeastern University, Shenyang 110006, China K.A.Khalil Powder Metallurgy Institute, Central South University, Changsha 410083, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第5期538-542,共5页
Alumina-(0 similar to 20 vol. pct) iron composites were fabricated by hot-pressing of well-mixed-alumina and iron powders at 1400 degreesC and 30 MPa for 30 min. Hot-pressed bodies with nearly theoretical density were... Alumina-(0 similar to 20 vol. pct) iron composites were fabricated by hot-pressing of well-mixed-alumina and iron powders at 1400 degreesC and 30 MPa for 30 min. Hot-pressed bodies with nearly theoretical density were obtained for addition up to 10 vol. pct Fe, but relative density decreased gradually with further increase in Fe addition. The materials exhibit a homogeneous dispersion of Fe. Fracture strength of the composites exhibits a maximum value of 604 MPa at 15 vol. pct Fe, which is 1.5 times that of alumina alone. Fracture toughness increases with the increase in Fe content, reaching 7.5 MPa.m(1/2) at 20 vol. pct Fe. The theoretical values of fracture toughness was calculated and compared with the experimental one. Toughening mechanisms of the composites are also discussed. 展开更多
关键词 FE Properties of hot-pressed Al2O3-Fe Composites AL
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Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed Sintering and Post Treatment 被引量:2
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作者 X.Y.Yue S.Y.Peng +2 位作者 X.Zhang C.N.He Y.Z.Tian 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2024年第2期255-265,共11页
A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution treated.The hot-pressed sintered and solution treated materials were rolled and aged.The precipitation behav... A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution treated.The hot-pressed sintered and solution treated materials were rolled and aged.The precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron microscopy.In contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe composite.The Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACS and softening temperature of 838 K.Mechanisms for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were analyzed.These findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment. 展开更多
关键词 Cu-Fe composite hot-pressed sintering Thermal stability STRENGTH Electrical conductivity
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Hot-pressed sintering of W/Cu functionally graded materials prepared from copper-coated tungsten powders 被引量:1
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作者 Pei Tian Yi Feng +4 位作者 Meng Xia Lan Zhao Cheng-Yu Cai Ke Liu Xiao-Chen Huang 《Rare Metals》 SCIE EI CAS CSCD 2020年第10期1229-1236,共8页
The three-layered(W-60 vol%Cu/W-40 vol%Cu/W-20 vol%Cu)W/Cu functionally graded material(FGM)containing a Cu network structure was fabricated at different temperatures by hot-pressed sintering produced from copper-coat... The three-layered(W-60 vol%Cu/W-40 vol%Cu/W-20 vol%Cu)W/Cu functionally graded material(FGM)containing a Cu network structure was fabricated at different temperatures by hot-pressed sintering produced from copper-coated tungsten powders.The effects of various sintering temperatures on relative density,microstructure,thermal conductivity,hardness and flexural strength were investigated.Scanning electron microscopy(SEM)and X-ray diffraction(XRD)analysis show that a Cu network extends throughout the W/Cu FGM specimens sintered at 1065℃and the graded structure can be retained perfectly,and W particles are distributed homogeneously.The low-temperature sintering densification of W/Cu FGM arises because the sintering mode of the copper-coated tungsten particles includes just sintering Cu to Cu,rather than Cu to W,Cu to Cu and W to W,as required for conventional powder particles.The relative density of W/Cu FGM sintered at 1065℃for 3 h under a load of25 MPa is 96.1%.The thermal conductivity is up to204 W·m^-1·K^-1 at normal temperature and 150 W·m^-1·K^-1at 800℃.And the Vickers hardness varies with the gradient of different layers from 3.34 to 4.05 GPa. 展开更多
关键词 Copper-coated tungsten powders hot-pressed sintering W/Cu functionally graded materials Microstructure Performance
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Microstructure and Toughness of Seeded Hot-Pressed Si_3N_4 Ceramics
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作者 D.Bucevac S.Boskovic +1 位作者 M.Vlajic V.Krstic 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第3期241-244,共4页
Densification, phase transformation and fracture toughness were studied in hot-pressed Si_3N_4 seeded by in-houseproduced large, elongated β-Si_3N_4 seeds. A mixture of Y_2O_3-Al_2O_3 was used as the sintering aid. C... Densification, phase transformation and fracture toughness were studied in hot-pressed Si_3N_4 seeded by in-houseproduced large, elongated β-Si_3N_4 seeds. A mixture of Y_2O_3-Al_2O_3 was used as the sintering aid. Concentration ofseeds were varied from 0 to 6 wt pct and the sintering time at 1700℃ was varied from 1 to 4 h. Maximum fracturetoughness of 9.0 MPam^(1/2) was measured in samples containing 5 wt pct seeds, hot pressed at 1700℃ for 4 h. 展开更多
关键词 In-situ composites SEEDS hot-pressING Silicon nitride
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Preparation of Fe-As alloys by mechanical alloying and vacuum hot-pressed sintering:microstructure evolution,mechanical properties,and mechanisms
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作者 Fei Chai Fei-Ping Zhao +7 位作者 Zhan Hu Shi-Yi Wen Ben-Hammouda Samia Ze-Lin Fu Xin-Ting Lai Yan-Jie Liang Xiao-Bo Min Li-Yuan Chai 《Rare Metals》 SCIE EI CAS CSCD 2024年第8期3876-3892,共17页
Arsenic materials have attracted great attention due to their unique properties.However,research concerning iron-arsenic(Fe-As) alloys is very scarce due to the volatility of As at low temperature and the high melting... Arsenic materials have attracted great attention due to their unique properties.However,research concerning iron-arsenic(Fe-As) alloys is very scarce due to the volatility of As at low temperature and the high melting point of Fe.Herein,a new Fe-As alloy was obtained by mechanical alloying(MA) followed by vacuum hot-pressed sintering(VHPS).Moreover,a systematic study was carried out on the microstructural evolution,phase composition,leaching toxicity of As,and physical and mechanical properties of Fe-As alloys with varying weight fractions of As(20%,25%,30%,35%,45%,55%,65%,and 75%).The results showed that pre-alloyed metallic powders(PAMPs) have a fine grain size and specific supersaturated solid solution after MA,which could effectively improve the mechanical properties of Fe-As alloys by VHPS.A high density(> 7.350 g·cm^(-3)),low toxicity,and excellent mechanical properties could be obtained for FeAs alloys sintered via VHPS by adding an appropriate amount of As,which is more valuable than commercial Fe-As products.The Fe-25% As alloy with low toxicity and a relatively high density(7.635 g·cm^(-3)) provides an ultra-high compressive strength(1989.19 MPa),while the Fe-65% As alloy owns the maximum Vickers hardness(HVo.5 899.41).After leaching by the toxicity characteristic leaching procedure(TCLP),these alloys could still maintain good mechanical performance,and the strengthening mechanisms of Fe-As alloys before and after leaching were clarified.Changes in the grain size,micro structure,and phase distribution induced significant differences in the compressive strength and hardness. 展开更多
关键词 Mechanical alloying Vacuum hot-pressed sintering High-pressure Arsenic-iron alloys Mechanical properties
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Pediatric Trans Olecranon Fracture-Dislocation of the Elbow Managed Nonoperatively: A Case Report and Review of Literature
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作者 Khalifa Ababacar Faye Alioune Badara Gueye +4 位作者 Blaise Kega Dieye Ibou Mouhamadou Moustapha Niane Yacine Sock Charles Alain Valerie Kinkpe 《Open Journal of Orthopedics》 2025年第1期41-45,共5页
Elbow dislocations are rare injuries in children due to the resistance of the capsuloligamentous structures. Anterior dislocation is very rare and its combination with an olecranon fracture is unusual. The authors rep... Elbow dislocations are rare injuries in children due to the resistance of the capsuloligamentous structures. Anterior dislocation is very rare and its combination with an olecranon fracture is unusual. The authors report a case of this lesion in a 7-year-old child managed nonoperatively. 展开更多
关键词 elbow Anterior Dislocation CHILDREN
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Comparative analysis of elbow radiographic measurements in patients with supracondylar humerus fractures and healthy controls
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作者 Nuri KÜlgen Batuhan Gencer Özgür Doğan 《World Journal of Orthopedics》 2025年第5期38-43,共6页
BACKGROUND Supracondylar humeral fractures(SCHF)are the second most common fractures in childhood and can lead to short-and long-term complications.Despite their prevalence,the anatomical factors that predispose child... BACKGROUND Supracondylar humeral fractures(SCHF)are the second most common fractures in childhood and can lead to short-and long-term complications.Despite their prevalence,the anatomical factors that predispose children to SCHF remain unclear.This study aimed to determine whether there are significant morpho-logical differences in the elbow by comparing the radiographic angular measure-ments of the contralateral elbows of patients with SCHF to those of patients with distal radius fractures(DRF)and a healthy control group.We sought to explore if these morphological variations contribute to the occurrence of SCHF.Radiographs of 78 SCHF patients were analyzed for angular measurements of the contralateral elbow.Two control groups were used:98 healthy children and 40 patients with DRF.Angular measurements included Baumann angle(BA),hu-meroulnar angle(HUA),humerus metaphysis-diaphysis angle(HMDA),humerus shaft-condylar angle(HSCA),and lateral capitellohumeral angle.Only BA,HUA,and HMDA were measured in the DRF group.Statistical analysis was performed to compare differences among groups.RESULTS Significant differences were found in elbow measurements between SCHF and control groups(P<0.05).However,the mean values for all groups fell within the ranges described in the literature.CONCLUSION While statistically significant differences were found in elbow morphology between SCHF patients and controls,these differences don't translate into clinically meaningful morphological deviations. 展开更多
关键词 Pediatric elbow Supracondylar humerus fractures Distal radius fractures elbow morphology Baumann angle
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Numerical Simulation of Gas-LiquId Flow in a Horizontal Elbow
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作者 Lihui Ma Wei Li +6 位作者 Yuanyuan Wang Pan Zhang Lina Wang Xinying Liu Meiqin Dong Xuewen Cao Jiang Bian 《Fluid Dynamics & Materials Processing》 2025年第1期107-119,共13页
Gas-liquid flow(GLF),especially slug and annular flows in oil and gas gathering and transportation pipelines,become particularly complex inside elbows and can easily exacerbate pipeline corrosion and damage.In thisstu... Gas-liquid flow(GLF),especially slug and annular flows in oil and gas gathering and transportation pipelines,become particularly complex inside elbows and can easily exacerbate pipeline corrosion and damage.In thisstudy,FLUENT was used to conduct 3D simulations of slug and annular flow in elbows for different velocitiesto assess the ensuing changes in terms of pressure.In particular,the multifluid VOF(Volume of Fraction)modelwas chosen.The results indicate that under both slug and annular flow conditions,the pressure inside the elbow islower than the outside.As the superficial velocity of liquid and gas increase,the pressure and liquid flow velocityat different positions of the elbow also increase,while the secondary flow weakens.Under annular flow conditions,the liquid film on the outer side of the elbow is thicker than that on the inner side,and the liquid velocityin the main liquid film zone is the lowest. 展开更多
关键词 Gas-liquid flow elbow CFD VOF model
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Winding Pattern Design and Simulation of S-elbow 被引量:3
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作者 王显峰 肖军 文立伟 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第5期573-577,共5页
Aimed at the S-elbow composed of two elbows with different radii, this article proposes a winding pattern design method combined with patch winding method and traditional winding method. It proposes an optimal combina... Aimed at the S-elbow composed of two elbows with different radii, this article proposes a winding pattern design method combined with patch winding method and traditional winding method. It proposes an optimal combination of calculating the tangential point amount and skip point amount to make the pattern distribution even and keep the minimal adjusting angle. The S-elbow overall winding pattem plan and simulation module are designed to verify the combined winding pattern design method and the calculation algorithm of the tangential point amount and skip point amount. From the pattern distribution and the simula- tion effect analysis, it shows that this combined winding pattern design method is a good solution to the S-elbow combined winding pattern design. Aimed at the S-elbow winding pattern based on the patch winding method, it carries out the precision error analysis and points out the correspondence between the error and mesh size. Generally speaking, the bigger the mesh size is, the quicker the program calculation speed is; the smaller the mesh size is, the smaller the winding pattern error is. 展开更多
关键词 S-elbow WINDING MESH COMPOSITE PATTERN
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基于多维特征与聚类分析的铁路物流客户群画像研究
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作者 马睿博 汤银英 +1 位作者 左鹏辉 郭赫臣 《铁道运输与经济》 北大核心 2026年第2期173-180,204,共9页
在“交通强国”和“双碳”战略背景下,针对铁路物流客户画像构建中传统K-means算法存在的特征单一、初始中心敏感等问题,创新性地融合多维特征嵌入与算法优化技术。通过构建动静结合的特征体系,采用肘部法则与轮廓系数优化聚类参数,结... 在“交通强国”和“双碳”战略背景下,针对铁路物流客户画像构建中传统K-means算法存在的特征单一、初始中心敏感等问题,创新性地融合多维特征嵌入与算法优化技术。通过构建动静结合的特征体系,采用肘部法则与轮廓系数优化聚类参数,结合多个评估指标,显著提升了客户分群的准确性,最后应用词云工具等进行客户群特征的可视化呈现。研究成果为铁路物流企业实现精准运力配置和差异化服务提供了有效解决方案,对提升行业数字化运营水平具有重要实践价值。 展开更多
关键词 铁路物流 客户画像 多维特征 肘部法则 轮廓系数
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基于频率响应对比的T(0,1)模态导波管道弯头缺陷检测
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作者 耿海泉 邹刚 +1 位作者 李合 王悦民 《兵器装备工程学报》 北大核心 2026年第1期262-268,共7页
针对超声导波弯头缺陷检测难题,使用数值模拟方法研究了不同频率T(0,1)模态导波对不同位置弯头缺陷的检测能力,并与完好弯头反射进行了对比,根据对比结果提出了一种基于频率响应对比的弯头缺陷检测方法。研究结果表明:T(0,1)模态导波对... 针对超声导波弯头缺陷检测难题,使用数值模拟方法研究了不同频率T(0,1)模态导波对不同位置弯头缺陷的检测能力,并与完好弯头反射进行了对比,根据对比结果提出了一种基于频率响应对比的弯头缺陷检测方法。研究结果表明:T(0,1)模态导波对弯头拱腹缺陷的检测敏感度大于拱背缺陷;随着频率增高,含缺陷弯头反射系数呈增大趋势,而完好弯头反射系数呈减小趋势;提出的基于频率响应对比的弯头缺陷检测方法能够检测出弯头缺陷,并得到数值模拟和实验数据的验证。研究结论将为T(0,1)模态导波管道弯头缺陷检测提供新的思路。 展开更多
关键词 超声导波 T(0 1)模态 弯头缺陷 频率响应对比
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基于冲蚀-动网格耦合的弯管冲蚀形变动态预测研究
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作者 范岳龙 秦晓杰 +4 位作者 贾蕊 张馨桦 裘川 孟阳 张强 《化工自动化及仪表》 2026年第2期300-308,共9页
为实现对弯管冲蚀变形的精准预测,采用冲蚀-动网格耦合数值模拟方法,量化了壁面形变与流场演变的交互作用机制。基于大庆油田压裂管道的实际参数,通过多因素正交实验设计,分析流速、砂比、粒径和曲率比对弯管冲蚀行为的耦合影响。结果表... 为实现对弯管冲蚀变形的精准预测,采用冲蚀-动网格耦合数值模拟方法,量化了壁面形变与流场演变的交互作用机制。基于大庆油田压裂管道的实际参数,通过多因素正交实验设计,分析流速、砂比、粒径和曲率比对弯管冲蚀行为的耦合影响。结果表明:各参数对最大冲蚀变形的影响敏感性排序为流速>曲率比>砂比>粒径;冲蚀损伤在外侧壁面呈中心辐射状分布,且最大冲蚀变形与流速、砂比、粒径呈正相关,与曲率比呈负相关。 展开更多
关键词 数值模拟 弯管冲蚀 冲蚀-动网格耦合 正交实验 敏感性分析
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Summary for experience of FANG Jian-qiao in treating tennis elbow
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作者 陈利芳 《World Journal of Acupuncture-Moxibustion》 2014年第1期51-54,共4页
Prof. FANG Jian-qiao is good at clinical and basic study on acupuncture analgesia. The therapeutic efficacy in treating tennis elbow of Prof. Fang is significant,"needling painful point" on the basis of clarifying c... Prof. FANG Jian-qiao is good at clinical and basic study on acupuncture analgesia. The therapeutic efficacy in treating tennis elbow of Prof. Fang is significant,"needling painful point" on the basis of clarifying causes and pathogenesis of this disease in TCM and western medicine,treat this disease by using encircling needling in combina on with warm needling moxibus on,and it is convenient,safe and eff ec ve. The encircling needling in combina on with warm needling moxibus on has obvious advantages in trea ng external humeral epicondyli s. 展开更多
关键词 tennis elbow experiences of famous doctor
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血液透析患者前臂动静脉内瘘失功能后建立肘部高位动静脉内瘘的临床效果
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作者 沈洁 王小燕 钱慕周 《中国当代医药》 2026年第1期41-45,共5页
目的探讨血液透析患者前臂动静脉内瘘(AVF)失功能后建立肘部高位AVF的临床效果。方法选取2021年1月至2024年10月南通市第四人民医院血液净化中心收治的80例规律透析、前臂AVF失功能的患者作为研究对象,按照不同手术方法分为观察组与对照... 目的探讨血液透析患者前臂动静脉内瘘(AVF)失功能后建立肘部高位AVF的临床效果。方法选取2021年1月至2024年10月南通市第四人民医院血液净化中心收治的80例规律透析、前臂AVF失功能的患者作为研究对象,按照不同手术方法分为观察组与对照组,每组40例。观察组同侧建立肘部高位AVF,对照组同侧前臂重建AVF。两组患者术前均进行血管的物理检查和超声评估,比较两组患者的手术成功率、术后不同时间段AVF血流速度与透析充分性、术后AVF的并发症。结果观察组术后肘部高位AVF血管震颤和搏动可触及,且术后3个月未见肿胀手的发生,观察组手术成功率高于对照组,差异有统计学意义(P<0.05)。观察组术后即刻,术后3、6个月AVF的血流速度高于对照组,差异有统计学意义(P<0.05);两组患者术后即刻,术后3、6个月的尿素清除指数(Kt/V)组间与组内比较,差异无统计学意义(P>0.05)。两组患者随访3个月后均未出现术后短期并发症。结论血液透析患者前臂AVF失功能后建立肘部高位AVF手术成功率高,高位AVF术后血流速度充足确保了患者的透析充分性。 展开更多
关键词 血液透析 前臂动静脉内瘘失功能 肘部高位动静脉内瘘 血流速度 透析充分性
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基于功能性近红外光谱技术观察缺血性脑卒中患者患侧上肢屈肘任务下的皮质激活特征
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作者 蒋金金 王璐怡 +1 位作者 张玉婷 汪杰 《康复学报》 2026年第1期39-45,共7页
目的基于功能性近红外光谱技术(fNIRS)观察缺血性脑卒中患者患侧上肢屈肘任务下的皮质激活特征。方法选取2023年1月—2024年6月在首都医科大学附属北京康复医院住院的缺血性脑卒中患者80例,左侧偏瘫和右侧偏瘫各40例。根据Fugl-Meyer运... 目的基于功能性近红外光谱技术(fNIRS)观察缺血性脑卒中患者患侧上肢屈肘任务下的皮质激活特征。方法选取2023年1月—2024年6月在首都医科大学附属北京康复医院住院的缺血性脑卒中患者80例,左侧偏瘫和右侧偏瘫各40例。根据Fugl-Meyer运动功能评定量表上肢部分(FMA-UE)评分将FMA-UE评分>43分患者分为轻度组,将FMA-UE评分≤43分的患者分为重度组,其中左侧偏瘫轻度组、重度组各20例;右侧偏瘫轻度组、重度组各20例;同时纳入20例健康受试者作为对照组。参照Brodmann大脑皮质分区将其划分为双侧背外侧前额叶皮层(DLPFC)、额极区(FPA)、初级运动皮层(M1)、辅助运动区(SMA)、前运动皮层(PMC)、躯体感觉皮层(SMC)和Broca共14个感兴趣区;采用fNIRS仪对患者患侧上肢屈肘任务下fNIRS数据进行采集,频率20 Hz,采用block设计,任务共180 s。采用氧合血红蛋白(HbO2)明确激活通道,并计算通道激活率。采用偏侧化指数(LI)评估在进行特定任务时,左右大脑半球激活优势程度。结果与对照组比较,左侧偏瘫轻度组SMA&PMC所有通道激活率更高(P<0.05),左侧偏瘫重度组全脑通道、SMA&PMC所有通道和右侧半球激活率更高(P<0.05);与左侧偏瘫轻度组比较,左侧偏瘫重度组全脑通道、SMA&PMC所有通道和右侧半球激活率更高(P<0.05);与对照组比较,右侧偏瘫轻度组DLPFC右侧半球激活率更高(P<0.05),右侧偏瘫重度组全脑通道、SMA&PMC所有通道、DLPFC所有通道和右侧半球激活率更高(P<0.05);与右侧偏瘫轻度组比较,右侧偏瘫重度组全脑通道、SMA&PMC所有通道和左侧半球、DLPFC所有通道和右侧半球激活率更高(P<0.05)。与对照组比较,左侧偏瘫轻度组和左侧偏瘫重度组右侧大脑半球激活更强;与左侧偏瘫轻度组比较,左侧偏瘫重度组右侧大脑半球M1区、PMC激活更强;与左侧偏瘫重度组比较,左侧偏瘫轻度组右侧大脑半球DLPFC和SMA激活更强。与对照组比较,右侧偏瘫轻度组和右侧偏瘫重度组两侧半球DLPFC和SMA激活相对平衡;与右侧偏瘫轻度组比较,右侧偏瘫重度组左侧大脑半球M1区激活更强;与右侧偏瘫重度组比较,右侧偏瘫轻度组左侧大脑半球PMC激活更强。右侧偏瘫轻度组各脑区的LI有接近对照组的趋势。结论缺血性脑卒中患者在患侧上肢屈肘任务下,重度患者的SMA&PMC、DLPFC激活率更高,轻度患者的LI更接近对照组,大脑皮质激活的差异与运动功能障碍严重程度、受损半球有关。 展开更多
关键词 缺血性脑卒中 功能性近红外光谱技术 大脑激活 偏侧化指数 上肢屈肘任务
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Effect of flow velocity on corrosion behavior of AZ91D magnesium alloy at elbow of loop system 被引量:7
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作者 田径 黄华良 +1 位作者 潘志权 周红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期2858-2867,共10页
A loop system was used to investigate the effect of flow velocity on corrosion behavior of AZ91 D magnesium alloy at an elbow of loop system based on array electrode technology by polarization, computational fluid dyn... A loop system was used to investigate the effect of flow velocity on corrosion behavior of AZ91 D magnesium alloy at an elbow of loop system based on array electrode technology by polarization, computational fluid dynamics(CFD) simulation and surface analysis. The experimental results showed that the corrosion rate increased with increasing flow velocity, and a critical flow velocity could exist in the corrosion of AZ91 D magnesium alloy. When flow velocity exceeded the critical flow velocity, fluid hydrodynamics was dominant in the corrosion of AZ91 D magnesium alloy. On the contrary, the electrochemical factors were dominant. 展开更多
关键词 magnesium alloy flow velocity elbow computational fluid dynamics(CFD) POLARIZATION
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逐瘀通络法联合微创钢板接骨术治疗肱骨干骨折临床研究
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作者 李浩亮 李东方 《河南中医》 2026年第3期415-420,共6页
目的:观察逐瘀通络法联合微创钢板接骨术治疗肱骨干骨折的临床疗效。方法:将接受微创钢板接骨术治疗的92例肱骨干骨折患者按照随机数字表法分为常规组和试验组,每组46例。常规组术后采用常规治疗,试验组在常规组治疗的基础上联合逐瘀通... 目的:观察逐瘀通络法联合微创钢板接骨术治疗肱骨干骨折的临床疗效。方法:将接受微创钢板接骨术治疗的92例肱骨干骨折患者按照随机数字表法分为常规组和试验组,每组46例。常规组术后采用常规治疗,试验组在常规组治疗的基础上联合逐瘀通络法治疗。观察两组患者手术时间、骨折愈合时间、肿胀消退时间、住院时间、疼痛消失时间、炎症因子[C反应蛋白(C reactive protein,CRP)、白细胞介素(interleukin,IL)-1β、IL-6、肿瘤坏死因子(tumor necrosis factor,TNF)-α]、疼痛视觉模拟评分(visual analogue score,VAS)、肩关节功能Neer评分、肘关节功能Mayo评分以及并发症发生情况。结果:试验组骨折愈合时间、肿胀消退时间、住院时间、疼痛消失时间短于常规组,差异有统计学意义(P<0.05),但试验组手术时间与常规组比较,差异无统计学意义(P>0.05);试验组术后2周CRP、IL-1β、IL-6、TNF-α水平低于常规组,差异有统计学意义(P<0.05);试验组术后2周、4周VAS评分均低于常规组,差异有统计学意义(P<0.05);试验组术后4周、12周肘关节功能Mayo评分、肩关节功能Neer评分高于常规组,差异有统计学意义(P<0.05);试验组并发症发生率为6.51%,常规组并发症发生率为10.86%,两组比较差异无统计学意义(P>0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:逐瘀通络法联合微创钢板接骨术可降低肱骨干骨折患者炎症因子水平,促进疼痛和肿胀消失,改善肘肩关节功能。 展开更多
关键词 肱骨干骨折 逐瘀通络法 微创钢板接骨术 炎症因子 肘关节功能 肩关节功能
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