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Effects of Solution Temperature on Tensile Properties ofSiC_w/2024Al Composite

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journal of Materials Science & Technology 1995年第4期11卷 291-294页

作者： MA, ZY LU, YX LUO, M bi, j ZHANG, YZ NE UNIV TECHNOL SHENYANG 110006PEOPLES R CHINA

The effects of solution (quench) temperature on the properties of SiCW/Al composite have been investigated using tensile tests. The experiments indicate that the solution temperature of the composite fabricated by P/M technique can be raised to 560 degrees C. The tensile strength of the composite is obviously dependent on solution (quench) temperature and the composite solutionized at 540 degrees C exhibits a maximum of tensile strength and elongation-to-failure. These results can be accounted for by the variation of the dislocation density in the composite.

关键词： Metallic matrix composites

Microstructure of TiB Whisker Reinforced Ti Matrix Composite

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journal of Materials Science & Technology 1997年第1期13卷 41-44页

作者： Lu, YX Li, DX Ping, DH bi, j Ma, ZY Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The composite of Ti matrix with TiB whisker reinforcement has been successfully fabricated. The content of TiB whisker in Ti matrix can reach about 30 vol. pet. Metallographic examination, morphology and microstructure of TiB whisker, interface structure between TiB whisker and Ti matrix were investigated using optical microscope, SEM, TEM and HREM technology. The diameter distribution of TiB whisker is from 0.1 mu m to 3.5 mu m and the aspect ratio of TiB whisker is from 10 to 20. The cross-section of whisker is generally polygon. Because of good compatibility between TiB whisker and Ti matrix it is identified that there is no obvious interaction of Ti matrix with TiB reinforcement and TiB whisker reinforced Ti matrix composites have excellent elevated properties.

关键词： Fiber reinforced materials

Microstructure and mechanical behavior of laser aided additive manufactured low carbon interstitial Fe_(49.5)Mn_(30)Co_(10)Cr_(10)C_(0.5)multicomponent alloy

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journal of Materials Science & Technology 2021年第18期77卷 38-46页

作者： Y.Chew Z.G.Zhu F.Weng S.B.Gao F.L.Ng B.Y Lee G.j.bi Singapore Institute of Manufacturing Technology 73 Nanyang Drive637662Singapore School of Mechanical Aerospace Engineering Nanyang Technological University50 N any ang Avenue639798Singapore

Laser aided additive manufacturing(LAAM)was used to fabricate bulk Fe_(49.5)Mn_(30)Co_(10)Cr_(10)C_(0.5)interstitial multicomponent alloy using pre-alloyed *** room temperature yield strength(σ_y),ultimate tensile strength(σ_(UTS))and elongation(ε_(UTS))were 645 MPa,917 MPa and 27.0%*** asbuilt sample consisted of equiaxed and dendritic cellular structures formed by elemental *** cellular structures together with oxide particle inclusions were deemed to strengthen the *** other contributing components include dislocation strengthening,friction stress and grain boundary *** highε_(UTS)was attributed to dislocation motion and activation of both twinning and transformation-induced plasticity(TWIP and TRIP).Tensile tests performed at-40℃and-130℃demonstrated superior tensile strength of 1041 MPa and 1267 MPa ***,almost no twinning was observed in the fractured sample tested at-40℃and-130℃.Instead,higher fraction of strain-induced hexagonal close-packed(HCP)εphase transformation of 21.2%were observed for fractured sample tested at-40℃,compared with 6.3%in fractured room temperature sample.

关键词： Multicomponent alloys Laser aided additive manufacturing Additive manufacturing Microstructure Mechanical property

Eutectic Solidification in Near-eutectic Al-Si Casting Alloys

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journal of Materials Science & Technology 2010年第12期26卷 1089-1097页

作者： H.C.Liao,M.Zhang,j.j.bi,K.Ding,X.Xi and S.Q.Wu School of Materials Science and Engineering,Southeast University jiangsu Key Laboratory for Advanced Metallic Materials,Nanjing 211198,China [a] School of Materials Science and Engineering Southeast University jiangsu Key Laboratory for Advanced Metallic Materials Nanjing 211198 China

Eutectic solidification in near-eutectic Al-13 wt pct Si casting alloys and the effect of trace addition of boron or strontium on it have been investigated using thermal analysis and microstructural characterization. In unmodified alloy, dual eutectic structure has been observed. The coarse eutectic （dendrite-like Al＋ coarse Si flakes） is formed above the equilibrium temperature of eutectic （Al＋Si） reaction （577℃）. The coarse eutectic （CE） grains nucleate from the primary silicon particles formed earlier due to local enrichment of silicon solute and grow in a divorced mode between the dendritic Al phase and large silicon flakes. The fine eutectic （FE） grains nucleate later on other potential sites activated by melt undercooling and grow in coupled-growing mode with the silicon crystals as fine flakes. The formation of the FE grains is favored in the alloys containing boron because of a great number of potential nucleation sites being added from boron-containing particles. Addition of strontium to the alloys restrains completely the formation of primary silicon particles and hence limits the nucleation of the CE. This is because the eutectic point has moved far enough to make the alloy, at this composition （Al-13 wt pct Si）, hypo-eutectic. Local cooling rate during solidification has an important influence on competition formation of these two eutectics.

关键词： Al-Si alloy Eutectic Solidification Dual eutectic grains Grain refinement

Impact of Climate Variability on Water Resources: The Case of Marc Delorme-Cnra Station, Southeast of Ivory Coast

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journal of Water Resource and Protection 2021年第9期13卷 726-749页

作者： Charly Fernand Agoh Tacra Thierry Lekadou Mahaman Bachir Saley bi Trazié jérémie Gala jean Homian Danumah Pierre-Marie janvier Coffi Zadjéhi Eric-Blanchard Koffi bi Tié Albert Goula Laboratory of Water and Environmental Sciences and Techniques (LSTEE) UFR of Earth Sciences and Mineral Resources (STRM) Felix Houphou&euml t Boigny University Abidjan Ivory Coast National Agronomic Research Center Marc Delorme Research Station Abidjan Ivory Coast Laboratory Geosciences and Environment Training and Research Unit of Environmental Sciences and Management (UFR) of Environmental Sciences and Management Nangui Abrogoua University (UNA) Abidjan Ivory Coast Laboratory of biology and Improvement of Plant Productions UFR Sciences de la Nature Peleforo Gon Coulibaly University Korhogo Ivory Coast

This study aims to characterize the climatic variability in the South-East of Ivory Coast and to show its impact on the supply of water resources. To do this, statistical and hydrological methods were applied to climatic data collected at the Marc DELORME Research Station of the CNRA. The statistical trend tests on this data revealed a significant decrease in precipitation and an increase in temperature, insolation and evaporation. Statistical break methods indicate a rainfall break in 1982 which marks a modification of the rainfall regime thus translating a drop in rainfall of 15%, a recession in the frequency of rainy days in general and in particular in rainfall heights between 10 and 30 mm and greater than 50 mm. This break is accompanied by a shortening of the rainy seasons, with average rainfall durations ranging from 54 days (short rainy season) to 104 days (great rainy season). Despite the disturbances in the different seasons of the year, the monthly rainfall regimes in the area have not changed. The assessment of the effects of drought on water resources using the Standardized Precipitation and Evapotranspiration Index (SPEI) for three-time scales (1 month, 3 months and 12 months) indicates a severe drought ranging from 3% to 7% over the period 1961 to 2018. However, despite the presence of this severe drought, the intensity of the drought was found to be moderate on all time scales. The Thorrnthwaite method was used to highlight the impacts of this climatic variability on the region’s water resources. The average annual recharge estimated at 402 mm, has been reduced to 153 mm during a deficit period, a decrease of about 62%. The average annual runoff, which was 294 mm, fells to 257 mm, a decrease of about 13%. This recorded decrease in the water infiltrated after the rainfall break (1983-2018), explains the heterogeneous decrease in the depth of the water table.

关键词： Climate Variability Drought Statistical Tests Water Resource Ivory Coast

利用铝业废渣和副产品作为钢铁工业精炼合成渣

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钢铁 2003年第Z1期38卷 208-212页

作者： Y.-D. Yang I.D. Sommerville A. McLean X. bi j. Hou Dept. Of Materials Science & Engineering University of Toronto Ontario Canada M5S-3E4 Dept. Of Materials Science & Engineering University of Toronto Ontario Canada M5S-3E4 Dept. Of Materials Science & Engineering University of Toronto Ontario Canada M5S-3E4 Dept. of Metallurgy Wuhan University of Science & Technology HuBei China Shandong Aluminum Co. Ltd. Zhibo Shandong China

讨论了利用铝业的废渣和副产品作为钢铁工业的精炼合成渣的可能性和实际结果,介绍了一些将铝业废渣转化为炼钢合成渣的成功工艺,概述了脱硫方面使用铝酸钙为基的合成渣的有关理论.通过合理利用冶金废渣材料,可减少对来自冶金工业的固体... 详细信息

讨论了利用铝业的废渣和副产品作为钢铁工业的精炼合成渣的可能性和实际结果,介绍了一些将铝业废渣转化为炼钢合成渣的成功工艺,概述了脱硫方面使用铝酸钙为基的合成渣的有关理论.通过合理利用冶金废渣材料,可减少对来自冶金工业的固体废渣的总处理量.

关键词：铝业铝酸钙环境铁水脱硫废渣

Robust interface and excellent as-built mechanical properties of Ti–6Al–4V fabricated through laser-aided additive manufacturing with powder and wire

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International journal of Minerals,Metallurgy and Materials 2025年第1期32卷 154-168页

作者： Fei Weng Guijun bi Youxiang Chew Shang Sui Chaolin Tan Zhenglin Du jinlong Su Fern Lan Ng Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong Engineering&Technology Research Center for Superhard MaterialSchool of Materials Science and EngineeringShandong UniversityJinan 250061China Institute of Intelligent Manufacturing Guangdong Academy of SciencesGuangzhou 510095China Singapore Institute of Manufacturing Technology 5 Cleantech Loop636732Singapore

The feasibility of manufacturing Ti-6Al-4V samples through a combination of laser-aided additive manufacturing with powder(LAAM_(p))and wire(LAAM_(w))was explored.A process study was first conducted to successfully circumvent defects in Ti-6Al-4V deposits for LAAM_(p) and LAAM_(w),*** the optimized process parameters,robust interfaces were achieved between powder/wire deposits and the forged substrate,as well as between powder and wire *** characterization results revealed the epitaxial prior β grains in the deposited Ti-6Al-4V,wherein the powder deposit was dominated by a finerα′microstructure and the wire deposit was characterized by lamellar α *** mechanisms of microstructure formation and correlation with mechanical behavior were analyzed and *** mechanical properties of the interfacial samples can meet the requirements of the relevant Aerospace Material Specifications(AMS 6932)even without post heat *** fracture occurred within the interfacial area,further suggesting the robust *** findings of this study highlighted the feasibility of combining LAAM_(p) and LAAM_(w) in the direct manufacturing of Ti-6Al-4V parts in accordance with the required dimensional resolution and deposition rate,together with sound strength and ductility balance in the as-built condition.

关键词： laser-aided additive manufacturing powder deposition wire deposition interfacial characteristic mechanical behavior

Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats

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Neural Regeneration Research 2025年第4期20卷 1164-1177页

作者： Pengfei Wang Yuewei bi Min Li jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang Neurosurgery Center Department of Pediatric NeurosurgeryGuangdong Provincial Key Laboratory on Brain Function Repair and RegenerationZhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

Long-term levodopa administration can lead to the development of levodopa-induced *** oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced ***,studies have reported increased oscillation power in cases of levodopa-induced ***,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced ***,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is *** found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s ***,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma *** of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum ***,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum *** findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia.

关键词： aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials neuromodulation Parkinson’s disease primary motor cortex

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盐酸氨溴索治疗老年肺炎的临床效果

中国当代医药 2015年第28期22卷 128-129,132页

作者：江碧静广东省河源市龙川县中医院内二科广东龙川517300

目的分析盐酸氨溴索治疗老年肺炎的临床效果。方法选取2013年10月~2014年10月我院收治的100例老年肺炎患者作为研究对象,将其随机分为对照组（n=50）和观察组（n=50）。对照组采取常规治疗,观察组在对照组基础上加用盐酸氨溴索进行治疗... 详细信息

目的分析盐酸氨溴索治疗老年肺炎的临床效果。方法选取2013年10月~2014年10月我院收治的100例老年肺炎患者作为研究对象,将其随机分为对照组（n=50）和观察组（n=50）。对照组采取常规治疗,观察组在对照组基础上加用盐酸氨溴索进行治疗。对两组的临床治疗效果和不良反应发生情况进行观察和对比。结果对照组的临床治疗总有效率为80%,低于观察组的94%（P〈0.05）;对照组咳嗽缓解时间、肺啰音消失时间以及体温恢复正常时间均迟于观察组（P〈0.05）;两组患者均未出现严重的不良反应。结论对老年肺炎患者采取常规治疗方法联合盐酸氨溴索,能够有效提高临床治疗效果,加速患者恢复健康,且未出现严重不良反应,值得临床推广应用。

关键词：老年肺炎盐酸氨溴索不良反应