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Effect of squeeze casting process on microstructures and flow stress behavior of Al-17.5Si-4Cu-0.5Mg alloy

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Journal of Iron and Steel Research International 2017年第9期24卷 957-965页

作者： yuan-ji shi Lan-ji Liu Lei Zhang Li-jun Zhang Li Zheng Run-xia Li Bao-yi Yu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina

The effects of squeeze casting process on microstructure and flow stress behavior of Al-17.5Si-4Cu-0.5Mg alloy were investigated and the hot-compression tests of gravity casting and squeeze casting alloy were carried out at 350-500°C and *** results show that microstructures of Al-17.5Si-4Cu-0.5Mg alloys were obviously improved by squeeze *** to the decrease of coarse primary Si particles,softα-Al dendrite as well as the fine microstructures appeared,and the mechanical properties of squeeze casting alloys were ***,when the strain rate rises or the deformation temperature decreases,the flow stress increases and it was proved that the alloy is a positive strain rate sensitive *** was deduced that compared with the gravity casting alloy,squeeze casting alloy（solidified at 632 MPa）is more difficult to deform since the flow stress of squeeze casting alloy is higher than that of gravity casting alloy when the deformation temperature exceeds 400°*** stress behavior of Al-17.5Si-4Cu-0.5Mg alloy can be described by a hyperbolic sine form with Zener-Hollomon parameter,and the average hot deformation activation energy Q of gravity casting alloy and squeeze casting alloy is 278.97 and 308.77kJ/mol,respectively.

关键词： Squeeze casting Al-Si-Cu-Mg alloy Hot compression deformation Flow stress Constitutive equation

Nanoindentation behavior and creep-induced cracking of long-term crept austenitic steel at 650℃

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Journal of Iron and Steel Research International 2024年第2期31卷 464-474页

作者： Zhen Zhang Yu-hang Duan Shuai Wang jin-shan Chen An-zhe Wang Xiang-yang Mao yuan-ji shi jie Zhang Ming Liu Zheng-fei Hu School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing211167JiangsuChina jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing211167JiangsuChina jiangsu Wind Power Engineering Technology Center Nanjing210023JiangsuChina Nanjing Vocational University of Industry Technology Nanjing210023JiangsuChina Baoshan Iron&Steel Co. Ltd.Shanghai201900China Fujian Provincial Key Laboratory of Terahertz Functional Devices and Intelligent Sensing School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116FujianChina School of Materials Science and Engineering Tongji UniversityShanghai201804China

The grain boundary(GB)damage of long-term crept HR3C(25Cr–20Ni–Nb–N)austenitic steel with solid solution state was investigated by nanoindentation test accompanied with in-situ electron back-scattered *** corresponding microstructure was characterized by scanning electron microscopy and transmission electron *** show that the increase in nanoindentation hardness at the GBs and triple grain junctions may be related to the dislocation accumulation and carbide growth during the *** M23C6 and dislocations piling-up at the GB accelerate the nucleation and coalescence of creep cavity along the *** nanoindentation hardness in grains varies with orientation of the stress *** orientation difference of neighbor grains may induce local high geometrically necessary dislocation densities and strain gradients near the GB,consequently causing stress concentration and subsequent crack growth at specific GBs.

关键词： Austenitic steel Creep Nanoindentation Grain orientation Creep-induced cracking

基于状态空间模型的雷达目标一维散射中心参数估计

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系统工程与电子技术 2011年第4期33卷 779-782页

作者：袁仕继高勋章金光虎王宏强国防科学技术大学电子科学与工程学院中国人民解放军63888部队

复杂雷达目标回波可看成是多散射中心回波的合成。首先建立了雷达目标回波的状态空间模型,然后利用超分辨方法估计一维散射中心的参数。在此基础上提出了一种基于状态空间的散射点数估计方法,该方法能够嵌入状态空间分析方法中,在进行... 详细信息

复杂雷达目标回波可看成是多散射中心回波的合成。首先建立了雷达目标回波的状态空间模型,然后利用超分辨方法估计一维散射中心的参数。在此基础上提出了一种基于状态空间的散射点数估计方法,该方法能够嵌入状态空间分析方法中,在进行超分辨分析的同时获取目标散射点数的精确估计,最后利用经典雷达回波模型对该方法进行了仿真实验验证。仿真结果表明,该方法能有效地提取一维散射中心参数并估计出散射点数,且具有良好的抗噪性。

关键词：状态空间模型散射中心散射点数超分辨分析

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中段翻滚目标运动建模及其宽带雷达回波仿真

信息与电子工程 2011年第1期9卷 33-38页

作者：袁仕继许世平博远中国人民解放军63888部队

弹道导弹飞行经历中段时,弹头与诱饵的主要差异是运动方式的不同,而诱饵大都呈现翻滚运动方式。文章从中段翻滚目标的物理、运动和散射特性出发建立了中段翻滚目标的运动模型,推导出了宽带线性调频(LFM)雷达回波的数学表达式。然后对中... 详细信息

弹道导弹飞行经历中段时,弹头与诱饵的主要差异是运动方式的不同,而诱饵大都呈现翻滚运动方式。文章从中段翻滚目标的物理、运动和散射特性出发建立了中段翻滚目标的运动模型,推导出了宽带线性调频(LFM)雷达回波的数学表达式。然后对中段翻滚目标的宽带雷达回波进行了仿真,并利用目标径向尺寸的周期变化估计出目标的翻滚周期。仿真结果表明中段翻滚目标宽带雷达回波与目标的姿态运动参数、形体参数都有较大关系,这将为中段目标的识别提供基础。

关键词：弹道导弹中段周期估计翻滚特征

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无人机作战网络动态联盟协作模型

电光与控制 2015年第1期22卷 11-15,19页

作者：杨会杰袁仕继王烟青中国洛阳电子装备试验中心河南洛阳471003

针对无人机作战网络多任务协作问题,提出一种基于动态联盟的无人机多任务协作模型。根据无人机网络的连通性和任务优先级,建立任务协作消息转发机制,合理控制动态联盟建立规模,以提高联盟的多任务处理效率。在离散事件系统仿真理论的基... 详细信息

针对无人机作战网络多任务协作问题,提出一种基于动态联盟的无人机多任务协作模型。根据无人机网络的连通性和任务优先级,建立任务协作消息转发机制,合理控制动态联盟建立规模,以提高联盟的多任务处理效率。在离散事件系统仿真理论的基础上,建立了一种基于优先级队列的无人机网络多任务协作仿真模型,采用时间步长推进方法,模拟了无人机网络的多任务协作过程。实验结果表明,与原有的动态联盟多任务协作方法和非协作的多任务处理机制相比,改进方法能够减少无人机网络的多任务处理时间,提高无人机作战的多任务处理效率。

关键词：无人机网络多任务协作动态联盟节点度

基于ZigBee技术的无线电台控制系统设计

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合肥工业大学学报（自然科学版） 2013年第4期36卷 440-443,455页

作者：张武袁仕继谢飞张劲心中国人民解放军63888部队

文章针对现有电磁环境构建方式上存在的成本较高、逼真度不足的缺点,提出了一种基于ZigBee技术的无线电台控制系统设计方案。该方案综合了ZigBee无线网络自组网、自愈合等优点,通过对各电台工作状态的实时监控,可在一定地域构建出满足... 详细信息

文章针对现有电磁环境构建方式上存在的成本较高、逼真度不足的缺点,提出了一种基于ZigBee技术的无线电台控制系统设计方案。该方案综合了ZigBee无线网络自组网、自愈合等优点,通过对各电台工作状态的实时监控,可在一定地域构建出满足任务需求的复杂电磁环境。初步试验结果表明,该系统运行稳定可靠,验证了设计的可行性。

关键词：电磁环境构建 ZigBee技术无线电台控制系统

Regulation and function of endoplasmic reticulum autophagy in neurodegenerative diseases

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Neural Regeneration Research 2025年第1期20卷 6-20页

作者： Xiu-Yun Zhao De-En Xu Ming-Lei Wu ji-Chuan Liu Zi-Ling shi Quan-Hong Ma Department of Neurology and Clinical Research Center of Neurological Disease the Second Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Neuroscience&jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases Soochow UniversitySuzhouJiangsu ProvinceChina Department of Neurology Jiangnan University Medical CenterWuxiJiangsu ProvinceChina

The endoplasmic reticulum,a key cellular organelle,regulates a wide variety of cellular *** reticulum autophagy,one of the quality control systems of the endoplasmic reticulum,plays a pivotal role in maintaining endoplasmic reticulum homeostasis by controlling endoplasmic reticulum turnover,remodeling,and *** this review,we briefly describe the endoplasmic reticulum quality control system,and subsequently focus on the role of endoplasmic reticulum autophagy,emphasizing the spatial and temporal mechanisms underlying the regulation of endoplasmic reticulum autophagy according to cellular *** also summarize the evidence relating to how defective or abnormal endoplasmic reticulum autophagy contributes to the pathogenesis of neurodegenerative *** summary,this review highlights the mechanisms associated with the regulation of endoplasmic reticulum autophagy and how they influence the pathophysiology of degenerative nerve *** review would help researchers to understand the roles and regulatory mechanisms of endoplasmic reticulum-phagy in neurodegenerative disorders.

关键词： autophagy endoplasmic reticulum endoplasmic reticulum autophagy endoplasmic reticulum quality control system endoplasmic reticulum receptors endoplasmic reticulum-associated degradation neurodegeneration neurodegenerative disease selective autophagy unfolded protein response

Tranylcypromine upregulates Sestrin 2 expression to ameliorate NLRP3-related noise-induced hearing loss

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Neural Regeneration Research 2025年第5期20卷 1483-1494页

作者： Xihang Chen Zhifeng Chen Menghua Li Weiwei Guo Shuolong yuan Liangwei Xu Chang Lin Xi shi Wei Chen shiming Yang Senior Department of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalChinese PLA Medical SchoolBeijingChina State Key Laboratory of Hearing and Balance Science BeijingChina National Clinical Research Center for Otolaryngologic Diseases BeijingChina Key Laboratory of Hearing Science Ministry of EducationBeijingChina Beijing Key Laboratory of Hearing Impairment Prevention and Treatment BeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Otolaryngology Head and Neck Surgery The 940th Hospital of Joint Logistics Support Force of Chinese PLALanzhouGansu ProvinceChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikouHainan ProvinceChina Academician Workstation of Hainan University School of Pharmaceutical SciencesYazhou BaySanyaHainan ProvinceChina

Noise-induced hearing loss is the primary non-genetic factor contributing to auditory ***,there are currently no effective pharmacological interventions for patients with noise-induced hearing ***,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory *** established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 *** found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with *** noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with *** findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell ***,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy *** treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)*** conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing *** findings suggest that inhibiting lysine-specific demethylase 1 is a

关键词： 4-hydroxynonenal apoptosis autophagy cleaved caspase-3 inflammation NOD-like receptor family pyrin domain-containing 3(NLRP3) noise-induced hearing loss oxidative stress Sestrin2 tranylcypromine

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F与CH3F反应的可见化学发光

化学学报 1987年第10期45卷 955-958页

作者：周士康邱元武史济良李方琳胡义华中国科学院安徽光学精密机械研究所激光光谱学实验室中国科学院上海有机化学研究所中国科学院安徽光学精密机械研究所激光光谱学实验室合肥

利用分子束装置研究了F与CH3F反应在可见光范围（450—900nm）的化学发光.观察到HCF（A1A″—X1A′）的七个振动带和HF电子基态振动广频跃迁的四个振动带和它们的强度随反应物流量的变化.求得HF分子的V′=4、5、6能级相对振动布居和V′=... 详细信息

利用分子束装置研究了F与CH3F反应在可见光范围（450—900nm）的化学发光.观察到HCF（A1A″—X1A′）的七个振动带和HF电子基态振动广频跃迁的四个振动带和它们的强度随反应物流量的变化.求得HF分子的V′=4、5、6能级相对振动布居和V′=3的转动温度.分析表明两种光谱都是第二步反应（F+CH2F）引起的,这步反应造成了HF高振动能级的统计性粒子分布和转动能级的玻尔兹曼分布.

关键词：反应物振动带真空室低压室振动布居光谱强度 HCF 化学发光单色仪 CH3F 抽气速率