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Effects of strain rates on dynamic deformation behavior of Cu-20Ag alloy

Journal of Materials Science & Technology 2021年第20期79卷 75-87页

作者： Kexing Song yongfeng geng Yijie Ban Yi Zhang Zhou Li Xujun Mi Jun Cao Yanjun Zhou Xuebin Zhang School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang471023China Provincial and Ministerial Co-Construction of Collaborative Innovation Center for Non-Ferrous Metal New Materials and Advanced Processing Technology Henan ProvinceLuoyang471023China Henan Province Key Laboratory of Nonferrous Materials Science and Processing Technology Luoyang471023China School of Materials Science and Engineering Central South UniversityChangsha410083China General Research Institute for Nonferrous Metals Beijing100088China Henan Polytechnic University Henan ProvinceJiaozuo454010China

Copper alloy is widely used in high-speed railway,aerospace and other fields due to its excellent electrical conductivity and mechanical properties.High speed deformation and dynamic loading under impact load is a complex service condition,which widely exists in the field of national defense,military and industrial application.Therefore,the dynamic deformation behavior of the Cu-20Ag alloy was investigated by Split Hopkinson Pressure Bar(SHPB)with the strain rates of 1000-25000 s^(-1),high-speed hydraulic servo material testing machine with the strain rates of 1-500 s^(-1).The effect of strain rate on flow stress and adiabatic shear sensitivity was analyzed.The results show that the increase of strain rate will increase the flow stress and critical strain,that is to say,the increase of strain rate will reduce the adiabatic shear sensitivity of the Cu-20Ag alloy.The Cu-Ag interface has obvious orientation relationship with;(111)_(Cu)//(111)_(Ag):(^(-)111)_(Cu)//(^(-)111)_(Ag):(^(-)200)_(Cu)//(^(-)200)_(Ag) and [0^(-)11]_(Cu)//[0^(-)11]_(Ag) with the increase of strain rate.The increase of strain rate promotes the precipitation of Ag and increases the number of interfaces in the microstructure,which hinders the movement of dislocations and improves the stress and yield strength of the Cu-20Ag alloy.The concentration and distribution density of dislocations and the precipitation of Ag were the main reasons improve the flow stress and yield strength of the Cu-20Ag alloy.

关键词： Cu-20Ag alloy Dynamic deformation Split Hopkinson Pressure Bar Adiabatic shear sensitivity

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Properties and precipitates of the high strength and electrical conductivity Cu-Ni-Co-Si-Cr alloy

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Journal of Materials Science & Technology 2021年第34期93卷 1-6页

作者： Yijie Ban yongfeng geng Jinrui Hou Yi Zhang Meng Zhou Yanlin Jia Baohong Tiana Yong Liua Xu Li Alex A.Volinsky School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology Luoyang 471023China Henan Key Laboratory of Nonferrous Materials Science and Processing Technology Luoyang 471023China School of Materials Science and Engineering Central South UniversityChangsha 410083China Center for Advanced Measurement Science National Institute of MetrologyBeijing 100029China epartment of Mechanical Engineering University of South Florida4202 E.Fowler Ave.ENG030Tampa 33620United States

In this paper,a novel Cu-1.5 Ni-1.1 Co-0.6 Si-0.1 Cr(wt.%)alloy with high strength and electrical conductivity was designed.After aging,excellent properties of 857±12 MPa yield strength,300±8 HV microhardness,42.8±2.5%IACS conductivity,and 7±0.5%elongation were obtained.According to the atomic structure,part of Ni atoms in Ni_(2)Si can be replaced by Co atoms to form nano-precipitates(Ni,Co)_(2)Si.The alloy’s high strength and conductivity are mainly attributed to the fine and uniformly distributed(Ni,Co)_(2)Si and Cr nano precipitates.The alloy strength was also enhanced by twins,dislocations,and grain refining strengthening.Based on the investigations of deformation microstructure and the orientation relationship between the(Ni,Co)_(2)Si precipitates and the Cu matrix,the main reason for elongation increase is attributed to the formation of deformation twins and the small lattice mismatch strain at the coherent interfaces of precipitates and the Cu matrix.

关键词： Copper Mechanical properties Precipitates Deformation twins

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基于调渣提铁的镍冶炼渣熔化温度调控

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中国有色金属学报 2024年第1期34卷 292-301页

作者：王冠杰赵俊学曹赓郑江华李彬马永峰崔雅茹宗红星西安建筑科技大学冶金工程学院西安710055 金川集团股份有限公司镍钴设计研究院金昌737100

目前,镍渣提铁工艺存在提铁效率低、工艺实施难度大、成本高等问题。本文通过相图分析、单因素和正交实验等方法,研究了炉渣中主要氧化物含量对半球点温度的影响,得到了有利于提铁的炉渣渣型优化方案。结果表明:当CaO含量(质量分数)为25... 详细信息

目前,镍渣提铁工艺存在提铁效率低、工艺实施难度大、成本高等问题。本文通过相图分析、单因素和正交实验等方法,研究了炉渣中主要氧化物含量对半球点温度的影响,得到了有利于提铁的炉渣渣型优化方案。结果表明:当CaO含量(质量分数)为25%、MgO含量为9%、铁硅比为0.8时,该渣型的半球点温度最低。考虑到现行工艺,选择MgO含量为13%、CaO含量为20%、铁硅比为1.0为较优方案,所得炉渣的半球点温度明显低于现行顶吹炉渣的半球点温度。调整后的炉渣中含铁物相由以硅酸亚铁为主转化为以钙铁榴石和铁氧化物为主,有利于后续提铁。

关键词：镍渣半球点温度正交试验渣型

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Metabolic profile differences in ACTH-dependent and ACTH-independent Cushing syndrome

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Chronic Diseases and Translational Medicine 2022年第1期8卷 36-40页

作者： Zhengyang Li Chen Zhang Chong geng yongfeng Song Department of Endocrinology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinanShandong 250021China Institute of Endocrinology and metabolism Shandong Academy of Clinical MedicineJinanShandong 250021China Department of Breast and Thyroid Surgery Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinanShandong 250021China Department of Endocrinology Shandong Provincial Hospital Affiliated to Shandong UniversityJinanShandong 250021China

Background:The most common etiologies of Cushing’’s syndrome(CS)are adrenocorticotropic hormone(ACTH)-producing pituitary adenoma(pitCS)and primary adrenal gland disease(adrCS),both of which burden patients with metabolic disturbance.The aim of this study was to compare the metabolic features of pitCS and adrCS patients.Methods:A retrospective review including 114 patients(64 adrCS and 50 pitCS)diagnosed with CS in 2009-2019 was performed.Metabolic factors were then compared between pitCS and adrCS groups.Results:Regarding sex,females suffered both adrCs(92.2%)and pitCS(88.0%)more frequently than males.Regarding age,patients with pitCS were diagnosed at a younger age(35.40±11.94 vs.39.65±11.37 years,p=0.056)than those with adrCS,although the difference was not statistically significant.Moreover,pitCS patients had much higher ACTH levels and more serious occurrences of hypercortisolemia at all time points(8 AM,4 PM,12 AM)than that in adrCS patients.Conversely,indexes,including body weight,BMI,blood pressure,serum total cholesterol,low density lipoprotein cholesterol(LDL-C),high density lipoprotein cholesterol(HDL-C),triglycerides,fasting plasma glucose,and uric acid,showed no differences between adrCS and pitCS patients.Furthermore,diabetes prevalence was higher in pitCS patients than in adrCS patients;however,there were no significant differences in hypertension or dyslipidemia prevalence between the two.Conclusions:Although adrCS and pitCS had different pathogenetic mechanisms,different severities of hypercortisolemia,and different diabetes prevalences,both etiologies had similar metabolic characteristics.

关键词： adrenal Cushing’s Cushing’s syndrome metabolic disturbance pituitary Cushing’s

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Repeating fast radio bursts from collapses of the crust of a strange star

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The Innovation 2021年第4期2卷 5-10页

作者： Jinjun geng Bing Li yongfeng Huang Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Particle Astrophysics Division Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210023China

Strange stars(SSs)are compact objects made of deconfined quarks.It is hard to distinguish SSs from neutron stars as a thin crust composed of normal hadronic matter may exist and obscure the whole surface of the SS.Here we suggest that the intriguing repeating fast radio bursts(FRBs)are produced by the intermittent fractional collapses of the crust of an SS induced by refilling of materials accreted from its low-mass companion.The periodic/sporadic/clustered temporal behaviors of FRBs could be well understood in our scenario.Especially,the periodicity is attributed to the modulation of accretion rate through the disk instabilities.To account for a~16-day periodicity of the repeating FRB source of 180916.J0158+65,a Shakura-Sunyaev disk with a viscosity parameter of 0.004 and an accretion rate of 3×10^(16)gs^(-1) is invoked.Our scenario,if favored by future observations,will serve as indirect evidence for the strange quark matter hypothesis.

关键词： accretion compact objects radio bursts degenerate matter low-mass X-ray binary stars

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磁悬浮左心室辅助装置植入术后患者Ⅰ期心脏康复的护理

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中华急危重症护理杂志 2024年第3期5卷 211-213页

作者：管玉珍陆艳艳王蔚云耿丹丹陈晴晴张伟邵永丰南京医科大学第一附属医院心脏大血管外科ICU 南京市210029

总结7例磁悬浮左心室辅助装置植入术患者Ⅰ期心脏康复的护理体会。针对患者在磁悬浮左心室辅助装置植入术后病情较重、运动能力下降、设备管理复杂等问题,采取心脏康复前评估、呼吸功能及运动功能训练、设备参数及安全管理、心电及平均... 详细信息

总结7例磁悬浮左心室辅助装置植入术患者Ⅰ期心脏康复的护理体会。针对患者在磁悬浮左心室辅助装置植入术后病情较重、运动能力下降、设备管理复杂等问题,采取心脏康复前评估、呼吸功能及运动功能训练、设备参数及安全管理、心电及平均动脉压监测、经皮线缆切口管理等措施。该组患者经35~61 d的积极治疗与护理后,痊愈出院,出院后随访3个月,患者恢复情况良好。

关键词：磁悬浮左心室辅助装置危重病护理心脏康复手术后医护

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宁夏畜禽粪污肥料化利用现状、存在问题及发展思路

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现代畜牧科技 2024年第5期 113-117页

作者：王明国耿荣崔勇王旭敏丁永峰李志广王晓媛张战胜宁夏农业技术推广总站宁夏银川750001 宁夏青铜峡市农业技术和农机化推广服务中心宁夏吴忠751600 宁夏固原市泾源县农业技术推广服务中心宁夏固原756400

畜禽粪污处理问题是制约宁夏乃至全国畜禽养殖业发展的瓶颈。该文在深入调查宁夏畜牧业发展及畜禽粪污肥料化利用情况的基础上,阐述了畜禽粪污资源及养殖业粪污处理现状,分析了养殖业粪污处理存在的困难与问题,以期为今后开展畜禽粪污... 详细信息

畜禽粪污处理问题是制约宁夏乃至全国畜禽养殖业发展的瓶颈。该文在深入调查宁夏畜牧业发展及畜禽粪污肥料化利用情况的基础上,阐述了畜禽粪污资源及养殖业粪污处理现状,分析了养殖业粪污处理存在的困难与问题,以期为今后开展畜禽粪污处理工作提供参考。

关键词：畜禽粪污肥料利用

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RESEARCH ON TECHNOLOGY OF CONTROLLED SOURCE RADIO MAGNETOTELLURIC SYSTEM'S TRANSMITTER

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Journal of Electronics(China) 2014年第6期31卷 609-618页

作者： Xu yongfeng Liu Lihua Wu Kai geng Zhi Fang Guangyou Key Laboratory of Electromagnetic Radiation and Sensing Technology Chinese Academy of Sciences University of Chinese Academy of Sciences

The basic theory and principle of the artificial Controlled Source Radio Magneto Telluric(CSRMT) method is studied and a novel CSRMT transmitter in kH z frequency band is designed. The specific circuit and measured results of some key modules in transmitter are presented, and some outdoor experimental tests have been carried out, which shows that the completed prototype of transmitter can generate a continuous sine current with frequency up to 35.33 k Hz, peak-to-peak amplitude up to 40 A, and realize a reliable transmitting mode with multi-frequency and high-current. The transmitter has a wide operating band, large magnetic moment and high waveform fidelity, and can meet the requirements of shallow geological exploration with high-resolution.

关键词： Controlled Source Radio Magneto Telluric(CSRMT) Transmitter technology Sine wave source Large current Broadband

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Characteristics of water volatilization and oxides generation by using positive and negative corona

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Plasma Science and Technology 2022年第4期24卷 61-70页

作者：陈可万良淏陈秉岩楚涛耿任悦宋德禹何湘苏巍殷澄单鸣雷蒋永锋 College of Science Hohai UniversityNanjing 210098People's Republic of China Nanjing Suman Plasma Science and Technology Co. LtdNanjing 211162People's Republic of China Jiangsu Key Laboratory of Power Transmission and Distribution Equipment Technology Changzhou 213022People's Republic of China College of Mechanical and Electrical Engineering Hohai UniversityNanjing 210098People's Republic of China

The physical and chemical properties have significant differences for the positive and negative charged particles generated by discharge.In this work,a positive and negative corona discharge system was established,and two discharge reactors for charged particles restraining and acting were designed by a needle electrode covered with a quartz tube and a plate electrode filled with water.The corona discharges happened within the needle-plate electrodes were excited by a positive and negative high voltage source,and the characteristics of both water volatilization and oxides generation were examined within influence of the distances of both quartz tube inside and outside.The results show that the characteristics of both the water volatilization and oxides generation can be affected by the distances of both quartz tube inside and outside.When the distances of tube inside were increased from 5.00 to 13.00 mm,the water volatilizations decreased under negative corona,and increased firstly and declined immediately under positive corona.The maximum value of the water volatilization appeared in the distances of tube inside with 6.00–8.00 mm.In addition,the concentrations of the HNO_(x) and H_(2)O_(2)in treated water decreased with increasing the distances of tube inside.Moreover,with increasing the distances of tube outside from 4.00 to 14.00 mm,the change trends of both the water volatilizations and oxides presented the same as the distances of tube inside,and the maximum value of the water volatilization and oxides appeared in the distance of tube outside with about 9.00 mm.Overall,the positive corona can generate more water volatilizations and oxides in water than negative corona,and non H_(2)O_(2)can be produced by negative corona.The results reflect the difference between positive and negative corona interaction with water,which can provide reference for plasma application.

关键词： positive corona negative corona water volatilization oxides generation

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生物活性物质递送体系下丝素蛋白微胶囊的研究进展

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丝绸 2022年第7期59卷 20-28页

作者：吴建兵耿涵枭顾舒婷孙银银王永峰常熟理工学院纺织服装与设计学院江苏苏州215500 中国科学院苏州纳米技术与纳米仿生所国际实验室江苏苏州215123

药物、香味剂、营养成分等生物活性物质易受到外界环境影响,导致其活性迅速降低。在使用过程中,如何长久稳定其活性是当前亟须解决的问题。丝素蛋白具有出色的生物相容性、安全性及优异的可塑性,基于丝素蛋白材料对生物活性物质具有高... 详细信息

药物、香味剂、营养成分等生物活性物质易受到外界环境影响,导致其活性迅速降低。在使用过程中,如何长久稳定其活性是当前亟须解决的问题。丝素蛋白具有出色的生物相容性、安全性及优异的可塑性,基于丝素蛋白材料对生物活性物质具有高度的亲和性和持久的稳定性。近年来,热点之一的丝素蛋白微胶囊在生物活性物质的装载、稳定和递送等方面已被深入研究。本文从递送体系角度出发,分别从丝素蛋白微胶囊的材料选择、成囊机理、制备方法和理化性能的影响因素及应用现状5个方面进行了综述,并重点比较了丝素蛋白微胶囊的制备方法及理化性能的影响因素。综合分析表明,丝素蛋白微胶囊的研究应着重围绕制备方法的开发、理化性能的提升、生物活性物质长久高效的稳定及特定递送体系下的功能化和智能化等方面入手,为应用于疾病治疗、食品保护、生物传感器等领域提供材料选择。

关键词：微胶囊丝素蛋白生物活性物质递送体系载体基质层层自组装

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