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Effects of the two-step ageing treatment on the microstructure and properties of 7B04 alloy pre-stretched thick plates

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Rare Metals 2007年第3期26卷 193-199页

作者： LI Zhihui XIONG Baiqing zhang yong ＇an zhu Baohong WANG Feng LIU Hongwei State Key Laboratory for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Beijing 100088 China

The effects of the two-step ageing parameters （temperature and time） on the mechanical properties and electrical conductivity of 7B04 （A1-Zn-Mg-Cu） pre-stretched thick plates were studied. The results reveal that the initial T1 ageing contributes a major increase of the tensile strength, and the 0.2% proof stress value reaches 482 MPa after ageing for 7 h at 115℃. Behavioral differences in the tensile properties of the alloy after the two-step ageing treatment were less with the first-step ageing at 115~C for different time periods （7, 14, and 21 h）. The effects of the second ageing parameters on the properties and microstructure of the 7B04 alloy were remarkable. TEM analysis of the samples aged at Temper I （7 h at 115℃ ＋ 12 h at 160℃） and Temper II （7 h at 115℃ ＋ 16 h at 165℃） indicates that two kinds of phases, i.e. 11＇ and 11 phases, precipitate from the matrix and efficiently improve the tensile strength of the alloy, and the grain boundary precipitates are coarse and discrete. There are obvious precipitate free zones （PFZs） along the grain boundary in the microstructure of the alloy after the two-step ageing treatment.

关键词： 7B04 alloy two-step ageing mechanical properties electrical conductivity microstructure

Identification of thermal effects involved in DSC experiment on Al-Cu-Mg-Ag alloys with high Cu:Mg ratio

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 671-675页

作者： Jian-bo zhang yong-an zhang Bao-hong zhu Feng Wang Zhi-hui Li Xi-wu Li Bai-qing Xiong State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Non-ferrous Metals Beijing 100088 China

Precipitation reactions in the differential scanning calorimetry （DSC） of an Al-Cu-Mg-Ag alloy were identified by analyzing the results from hardness test,electrical conductivity test,and transmission electron microscope （TEM） *** is discovered that thermal effects can be identified through selected area electron diffraction and bright-field *** reaction peaks around 171,231,and 276℃ can be attributed to a structural rearrangement of coherent zones,to the precipitation of Ω phases,and to the precipitation of Ω and θ＇ and possible combination with the transition of θ＇→θ,*** addition,the hardness and electrical conductivity of the alloy change proportionately with the progression of reactions during the heating *** phenomenon can be attributed to the evolution of the micro-structure.

关键词： aluminum alloys thermal effects identification differential scanning calorimetry microstructure

Functional reconstruction of ischemic contracture in the lower limb

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Chinese Journal of Traumatology 2011年第2期14卷 96-99页

作者： TANG Hao zhang Shao-cheng TAN zhang-yong zhu Hong-wei zhang Qiu-lin LI Ming Department of Orthopedics Changhai Hospital Second Military University Shanghai 200433 China

Objective： To discuss the method of functional reconstruction of ischemic contracture in the lower limb and propose a classification protocol for ischemic contracture in the lower limb based on its severity and prognosis. Methods： Atotal of 42 patients with ischemic contracture in the lower limb were included in this study. According to different types of disturbance and degrees of severity, surgical reconstructions consisting of nerve decompression, tendon lengthening or transfer, intrinsic foot muscle release and sural-tibial nerve anastomosis were performed in every patient. Results： Postoperatively, all patients were able to walk on flat ground. Drop foot was corrected in 10 patients, and 5 patients still felt some difficulty during stair activity. Split Achilles tendon transfer to flexor hallucis longus tendon was performed in 12 patients, and their walking stability was improved. Seven patients accepted ipsilateral suraltibial nerve anastomosis, and sensitivity recovery reached to S2 in 2 patients and S3 in 5 patients. Conclusions： Iscbemic contracture in the lower limb is a devastating complication after lower limb trauma. The prevention of contracture is much more important than the treatment of an established contracture. Split Achilles tendon transfer to flexor hallucis longus tendon and sural-tibial nerve anastomosis, which was initially implemented by us, could improve the functional recovery of ischemic contracture in lower limbs, and thus provides a new alternative for functional reconstruction of ischemic contracture in the lower limb.

关键词： Ischemic contracture Classification Recovery of function

Lagging and Its Kinetic Mechanism of Hydrocarbon Re-generation from Organic Matters in Coal

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Journal of Earth Science 2000年第1期19卷 86-90页

作者： Qin yong zhang Yousheng zhu Yanming Fan Bingheng Jiang Bo Li Tianzhong College of Mineral Resources and Environment Science, China University of Mining and Technology, Xuzhou 221008

Based on the composite analysis of the coal sample series with natural and artificial maturation, the lagging and its kinetic mechanism of the hydrocarbon re-generation from the organic matters in coals were studied using the Rock-Eval gas chromatogram (PyGC) method. The results show that the maturation at the hydrocarbon regeneration peak shifts regularly forward with increasing the starting maturation and the deadline of the hydrocarbon regeneration lies about at 4.0% R o. The difference value between the peak and starting maturation of the hydrocarbon re-generation develops in a parabolalike pattern with increasing the starting maturation, and the resolute and relative laggings evolve in stage, from which the lagging depth could be predicted. The peak halfwidth of the hydrocarbon re-generation curve develops as the starting maturation increases, which might indicate that the hydrocarbonderived rocks with the starting maturation lied about at oilgenerated peak might be relatively high in the hydrocarbonregenerated amount. In the meantime, the mean reactivated energy of the coal samples with starting maturation develops in four stages that are highly consistent with those of the hydrocarbonregenerated amount and lagging, which indicated that the hydrocarbon re-generation is strictly controlled by the geochemical mechanism of the reactive kinetics.

关键词： coal organic matter hydrocarbon re-generation lagging kinetics.

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong zhang Zhiying Chen Yinyi Xiong Qin Zhou Ling-Qiang zhu Dan Liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang Clinical Precision Medicine Research Center JiujiangJiangxi ProvinceChina Center for Cognitive Science and Transdisciplinary Studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia

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彩色多普勒超声对睾丸扭转的诊断价值

复旦学报（医学版） 2002年第3期29卷 223-224,F002页

作者：陈海蛟顾勇主张立叶传忠张永康复旦大学附属中山医院泌尿外科上海200032 复旦大学附属中山医院泌超声科上海200032

目的　评价彩色多普勒超声 (CDFI)对睾丸扭转诊断的临床应用价值。方法　本院自 1 996年 5月至2 0 0 1年 3月的 1 7例睾丸肿痛患者 ,经CDFI检查 ,通过观察阴囊内容物的形态、回声及血流变化 ,最大收缩期流速 (υmax)、舒张末期最小流速 ... 详细信息

目的　评价彩色多普勒超声 (CDFI)对睾丸扭转诊断的临床应用价值。方法　本院自 1 996年 5月至2 0 0 1年 3月的 1 7例睾丸肿痛患者 ,经CDFI检查 ,通过观察阴囊内容物的形态、回声及血流变化 ,最大收缩期流速 (υmax)、舒张末期最小流速 (υmin)和阻力指数 (RI)诊断为睾丸扭转 ,除 1例手法复位外 ,余进一步行手术探查。对照组为 1 7位无阴囊疾病者。结果　 1例手法复位后CDFI复查 ,血流恢复正常 ,症状缓解 ,余 1 6例经手术及病理均确诊为睾丸扭转。两组睾丸动脉υmax、舒张末期υmin和RI数值经统计学检查差别有显著意义 (P <0 .0 5)。

关键词：睾丸扭转彩色多普勒超声诊断

Structural and microwave absorption properties of CoFe_(2)O_(4)/residual carbon composites

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 221-232页

作者： Yuanchun zhang Shengtao Gao Xingzhao zhang Dacheng Ma Chuanlei zhu Jun He Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining Anhui University of Science and TechnologyHuainan 232001China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

Electromagnetic interference,which necessitates the rapid advancement of substances with exceptional capabilities for bsorbing electromagnetic waves,is of urgent concern in contemporary *** this work,CoFe_(2)O_(4)/residual carbon from coal gasification fine slag(CFO/RC)composites were created using a novel hydrothermal *** mechanisms for microwave absorption,including conductive loss,natural resonance,interfacial dipole polarization,and magnetic flux loss,are involved in these ***,compared with pure residual carbon materials,this composite offers superior capabilities in microwave *** 7.76GHz,the CFO/RC-2 composite achieves an impressive minimum reflection loss(RL_(min))of-43.99 dB with a thickness of 2.44 ***,CFO/RC-3 demonstrates an effective absorption bandwidth(EAB)of up to 4.16 GHz,accompanied by a thickness of *** study revealed the remarkable capability of the composite to diminish electromagnetic waves,providing a new generation method for microwave absorbing materials of superior quality.

关键词： coal gasification slag residual carbon hydrothermal method microwave absorption CoFe_(2)O_(4)

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保险“理赔难”的原因及解决对策

金融理论与实践 2005年第11期 65-67页

作者：孙大俊张永珠中国太平洋财产保险股份有限公司河南分公司河南郑州450053

探讨保险“理赔难”的原因所在,并从保监会、投保人和保险人以及行业发展方向等各方面入手,思考如何解决保险“理赔难”的问题。

关键词：保险理赔历年制赔付率满期保费理赔文化保险公估

基于区位氧势硫势梯度变化下铜富氧底吹熔池熔炼非稳态多相平衡过程

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中国有色金属学报 2015年第4期25卷 1072-1079页

作者：郭学益王亲猛田庆华张永柱中南大学冶金与环境学院长沙410083

结合富氧底吹熔池熔炼机理模型和Cu-Fe-S-O-Si O2系氧势-硫势热力学优势图,研究底吹熔炼过程中的多相平衡状态及炉内不同空间位点的氧势-硫势分布规律。结果表明:铜富氧底吹熔池熔炼是烟气-炉渣-铜锍三相共存体系,随着连续加料、连续鼓... 详细信息

结合富氧底吹熔池熔炼机理模型和Cu-Fe-S-O-Si O2系氧势-硫势热力学优势图,研究底吹熔炼过程中的多相平衡状态及炉内不同空间位点的氧势-硫势分布规律。结果表明:铜富氧底吹熔池熔炼是烟气-炉渣-铜锍三相共存体系,随着连续加料、连续鼓氧及放渣和放锍操作的进行,体系远未达到平衡,而是处于动态的非稳态近似多相平衡状态,炉内不同空间位点的氧势-硫势不同,存在着梯度变化。反应区、分离过渡区及液相澄清区由下到上氧势逐渐降低,而硫势逐渐升高,其中反应区的氧势-硫势差梯度较大,氧和硫的传质较快。通过调节熔炼过程工艺参数,使炉内不同空间位点的氧势-硫势控制在更为合理的范围,可提高底吹熔炼能力。

关键词：铜冶炼富氧底吹熔炼机理氧势硫势非稳态多相平衡