检索结果-南通市图书馆

Science China(Technological Sciences) 2020年第2期63卷 341-356页

作者： xiong guojun CHEN JinJian LI MingGuang Li YaoLiang State Key Laboratory of Ocean Engineering Department of Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Foundation Engineering Group Co. LtdShanghai 200433China

Existing solutions for axisymmetric active earth pressure are based on certain hypotheses of the circumferential stress, lacking of strict basis. This article presents a technique for deriving the actual circumferential stress according to the circumferential geometric condition, the Drucker-Prager criterion and incremental theory. Based on the actual circumferential stress, a new characteristics method for determining the axisymmetric active earth pressure in plastic flow is developed in this article. In this new method, the inclined angle of boundaries, interface friction of contact interface, dilatation effect and flow velocity of soil are considered at the same time. The validity of the new method is confirmed using several sets of experimental data from the literature. The pressure coefficients are investigated individually in detail, and some different conclusions are found. Finally, a practical formula for calculating axisymmetric active earth pressure is presented based on the linear superposition principle, and related tables of coefficients are also provided for engineering application.

关键词： axisymmetric active earth pressure characteristics method practical calculation formula earth pressure coefficients dilatation effect the Drucker-Prager yield criterion

基于泥浆平衡地压的桩孔稳定性分析及支护建议

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上海交通大学学报 2021年第9期55卷 1108-1115页

作者：熊国军王建华陈锦剑上海交通大学船舶海洋与建筑工程学院上海200240

基于泥浆压力平衡地压的原理,建立一种分析桩孔稳定的力学模型,分析无支护开挖、泥浆护壁成孔、硬支护成孔3种施工方式的应用条件与使用范围,给出无支护成孔最大深度、护壁泥浆下限容重的确定办法与实用表格.研究结果表明:土体的摩擦角... 详细信息

基于泥浆压力平衡地压的原理,建立一种分析桩孔稳定的力学模型,分析无支护开挖、泥浆护壁成孔、硬支护成孔3种施工方式的应用条件与使用范围,给出无支护成孔最大深度、护壁泥浆下限容重的确定办法与实用表格.研究结果表明:土体的摩擦角、黏聚力与泥浆容重是维持桩孔稳定的基本要素;当成孔深度小于无支护成孔最大深度时,可采用无支护开挖,否则须采用泥浆护壁辅助成孔,且泥浆重度不得小于场地土要求的护壁泥浆下限容重;当摩擦角大于25°时,可任意选择泥浆重度;当查表计算所得的护壁泥浆下限容重大于规范给定的最大泥浆容重时,则需采用套管等硬支护措施.

关键词：桩孔稳定护壁泥浆泥浆重度无支护临界深度

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国医大师伍炳彩异病同治验案分析

江西中医药 2024年第2期55卷 37-39页

作者：熊国军伍建光江西中医药大学研究生院南昌330004 江西中医药大学附属医院南昌330006

异病同治是中医治疗的重要原则,不仅体现了中医临床特色,还彰显了辨证论治的精髓。国医大师伍炳彩临床擅用银翘马勃散合酸枣仁汤,认为其所治病证病机特点为“湿热闭阻上焦,肝郁血虚”。通过分析伍炳彩临床使用该方治疗失眠、心悸、闭经... 详细信息

异病同治是中医治疗的重要原则,不仅体现了中医临床特色,还彰显了辨证论治的精髓。国医大师伍炳彩临床擅用银翘马勃散合酸枣仁汤,认为其所治病证病机特点为“湿热闭阻上焦,肝郁血虚”。通过分析伍炳彩临床使用该方治疗失眠、心悸、闭经等3个病案,体现该方临床辨证要点,体现了中医异病同治的精妙。

关键词：伍炳彩银翘马勃散酸枣仁汤异病同治验案

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伍建光教授治疗失眠验案三则

亚太传统医药 2024年第8期20卷 141-144页

作者：熊国军伍建光江西中医药大学江西南昌330004 江西中医药大学附属医院心血管病科江西南昌330006

伍建光教授论治失眠,病因侧重于痰湿,病位多从肝立足,临床见虚实夹杂之证常以经方合用,谨守病机,屡获佳效。介绍伍建光教授临床3例失眠验案,总结其诊治失眠的经验,供临床参考。

关键词：失眠伍建光中医治疗

Elevated temperature endurance and creep properties of extruded 2D70 Al alloy rods

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Rare Metals 2011年第3期30卷 310-315页

作者： WANG guojun xiong Baiqing ZHANG Yong＇an LI Zhihui State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals Beijing 100088 China Northeast Light Alloy Co. Ltd. Harbin 150060 China

The elevated temperature performances of 2D70 Al alloy hot extrusion rods after two-stage homogenization and intensive deformation were studied by measuring the elevated temperature enduring strength and the creep ultimate strength. The fracture morphology of some selected samples after testing at different elevated temperatures was observed by scanning electron microscopy （SEM）. The results indicate that, as the test temperature increases, the elevated temperature enduring strength of 2D70 Al alloy decreases gradually. In a comparison between 150 C and 240 C, the notch enduring strength drops from 375 to 185 MPa and the smooth enduring strength drops from 337 to 130 MPa. Enduring strength is not sensitive to the notch. The notch sensitivity ratio （NSR） coefficient is in the range of 1.119 to 1.423 from 150 C to 240 C. The creep test results show that, as the test temperature increases from 150 C to 240 C, the creep ultimate strength of 2D70 Al alloy rods drops gradually from 312 to 117 MPa.

关键词： aluminum alloys high temperature properties strength of materials creep notched bar tensile testing

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18例心肌致密化不全患者的临床特征分析

中国心血管杂志 2020年第4期25卷 328-332页

作者：熊国均欧荣华周芳明雷宇兰青邓晓剑德阳市人民医院心内科 618000

目的探讨心肌致密化不全患者的临床特征。方法回顾性分析18例心肌致密化不全患者的临床表现、心电图、心脏磁共振和超声心动图等资料,并随访(17±5)个月。结果 18例心肌致密化不全患者的发病年龄为36~71岁,其中男性10例(55.6%)。临床表... 详细信息

目的探讨心肌致密化不全患者的临床特征。方法回顾性分析18例心肌致密化不全患者的临床表现、心电图、心脏磁共振和超声心动图等资料,并随访(17±5)个月。结果 18例心肌致密化不全患者的发病年龄为36~71岁,其中男性10例(55.6%)。临床表现为心力衰竭15例(83.3%)、心悸8例(44.4%)、心律失常导致黑矇、晕厥2例(11.1%)、胸痛2例(11.1%)和血栓栓塞1例(5.6%),此外无临床症状1例(5.6%)。17例(94.4%)患者有心电图异常,包括室性期前收缩、ST-T改变、左束支传导阻滞、心房颤动、异常Q波、R波递增不良及室性心动过速。超声心动图及心脏磁共振显示,左心室病变17例(94.4%),双心室病变1例(5.6%),最常累及部位为左室心尖部(18例,100%),表现为心脏增大、心室收缩和舒张功能减退及瓣膜关闭不全,14例(77.8%)患者的左室射血分数<50%。随访期间,4例患者出现难治性心力衰竭,1例患者植入心脏再同步治疗除颤器,1例发生心原性猝死。结论心肌致密化不全患者主要表现为心力衰竭、心律失常,临床症状缺乏特异性。超声心动图在其诊断和随访中有重要价值,心脏磁共振是更佳的诊断工具。

关键词：心肌疾病心力衰竭心律失常心肌致密化不全超声心动描记术心脏磁共振

纤维蛋白原与白蛋白比值对多支血管病变性急性心肌梗死患者PCI术后远期预后的预测价值

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疑难病杂志 2019年第12期18卷 1212-1217页

作者：熊国均黄楷森欧荣华陈检雷宇胡丽君四川省德阳市人民医院心血管内科

目的分析纤维蛋白原与白蛋白比值(FAR)对多支血管病变(MVD)性急性心肌梗死(AMI)患者PCI术后远期预后的预测价值。方法选取2012年8月-2014年8月四川省德阳市人民医院心血管内科收治多支血管病变性AMI行PCI术后患者208例作为研究对象(最... 详细信息

目的分析纤维蛋白原与白蛋白比值(FAR)对多支血管病变(MVD)性急性心肌梗死(AMI)患者PCI术后远期预后的预测价值。方法选取2012年8月-2014年8月四川省德阳市人民医院心血管内科收治多支血管病变性AMI行PCI术后患者208例作为研究对象(最终纳入分析200例),根据入院即刻FAR四分位水平分为4组,各组50例,即A组:FAR B组> C组> D组,差异有统计学意义(Z/P=10.006/0.000,12.868/0.000);4组患者全因死亡率和MACE发生率随FAR升高而增加(χ^2/P=8.760/0.033,17.333/0.000),在全因死亡中,4组患者的心源性死亡率比较差异有统计学意义(χ^2/P=9.377/0.025),非心源性死亡率比较差异无统计学意义(P>0.05);在MACE事件中,4组患者心肌梗死发生率差异有统计学意义(χ^2/P=9.255/0.026);R0C曲线显示,FAR预测AMI合并MVD患者PCI术后全因死亡的曲线下面积(AUC)为0.858,最佳临界值为9.72;MACE的AUC为0.782,最佳临界值9.08,均具有较高的诊断价值。结论 FAR是MVD性AMI患者远期预后发生全因死亡和MACE的独立预测因子,且诊断价值较高,具有潜在的临床参考价值。

关键词：心肌梗死,急性多支病变纤维白蛋白白蛋白纤维白蛋白与白蛋白比值

Aging behavior and fatigue crack propagation of high Zn-containing Al-Zn-Mg-Cu alloys with zinc variation

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Progress in Natural Science:Materials International 2017年第2期27卷 217-227页

作者： Kai Wen Yunqiang Fan guojun Wang Longbing Jin Xiwu Li Zhihui Li Yongan Zhang Baiqing xiong State Key Laboratory of Non-ferrous Metals and Processes General Research Institute for Nonferrous Metals Northeast Light Alloy Co. Ltd.

In the present work, the influence of two-step aging treatments on hardness, electrical conductivity and mechanical properties of two high Zn-containing Al-Zn-Mg-Cu alloys with zinc content variation was investigated and the detailed T76 aging parameters were proposed. The microstructure of the precipitates were studied by transmission electron microscopy(TEM) and high-resolution transmission electron microscopy(HREM) and then quantitatively investigated with the aid of an image analysis. The fatigue performances were researched by the fatigue crack propagation(FCP) rate test and fracture morphology was observed with scanning electron microscopy(SEM). The results show that the matrix precipitate size distributions of both alloys had significant difference, so as to fatigue crack propagation rates and fracture appearance. The shear and bypass mechanisms of dislocation-precipitate interactions were employed to explain the difference. Among the shearable precipitates, the proportion of larger size precipitates for the higher zinc content alloy is bigger than that for the lower zinc content alloy. The coarse shearable precipitates hinder the propagation of the fatigue cracks, leading to inferior FCP rate. For both alloys, the shear mechanism possesses the dominant factor, finally causing a preponderance in the FCP resistance for the higher zinc content alloy than the lower one.

关键词： Al-Zn-Mg-Cu alloy Fatigue crack propagation Precipitate Aging treatment

Structural and thermal sensitivity of Cu-Zr-Ti amorphous alloys to tension

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Science China(Physics,Mechanics & Astronomy) 2013年第8期56卷 1606-1610页

作者： CAI AnHui xiong Xiang LIU Yong AN WeiKe ZHOU guojun LUO Yun LI TieLin LI XiaoSong College of Mechanical Engineering Hunan Institute of Science and Technology State Key Laboratory of Powder Metallurgy Central South University

Structural and thermal sensitivity of Cu(60-x)Zr(30+x) Ti 10 (x=0,5,and 10 at%) amorphous alloys to the application of tension was investigated. The structural sensitivity to tension decreases with increasing Cu content. The crystallization enthalpy increases with increasing excess free volume. The characteristic temperatures of the tensile samples can surpass those of the as-cast ones under a critical heating rate which differs in the Cu content. The increase of the excess free volume significantly influences the glass transition and crystallization procedures.

关键词： Cu-based amorphous alloy tension sensitivity

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老年人静脉血栓栓塞症的研究进展

中国普外基础与临床杂志 2018年第8期25卷 1004-1010页

作者：吴洲鹏赵纪春马玉奎黄斌袁丁杨轶曾国军熊飞陈熹阳四川大学华西医院血管外科成都610041

目的总结现阶段老年人静脉血栓栓塞症的研究进展。方法复习近年来国内外有关老年人静脉血栓栓塞症的流行病学、危险因素、诊断、防治及预后方面的文献并进行综述。结果静脉血栓栓塞症对于老年人来说是较为常见的一类心血管系统疾病,其... 详细信息

目的总结现阶段老年人静脉血栓栓塞症的研究进展。方法复习近年来国内外有关老年人静脉血栓栓塞症的流行病学、危险因素、诊断、防治及预后方面的文献并进行综述。结果静脉血栓栓塞症对于老年人来说是较为常见的一类心血管系统疾病,其发生率较高,但老年人对其预防重视程度不够,其临床表现无年轻人明显。对老年人静脉血栓栓塞症,各种检查手段各有其优缺点,治疗以抗凝为主,但需注意出血风险。结论老年人静脉血栓栓塞症的发病率高,诊断措施多样,需要分类对待,治疗过程中的利弊尤其需要注意,加强其专门的研究更有必要。

关键词：静脉血栓栓塞症老年人防治预后