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深冷处理对Cr7V钢高温耐磨性与位错密度的影响

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金属热处理 2019年第1期44卷 40-44页

作者：马治军刘亿吴斌斌林建平上海赛科利汽车模具技术应用有限公司上海汽车车身先进制造工程技术研究中心上海201209 同济大学机械与能源工程学院上海201804

对Cr7V模具钢进行了(1030℃×0. 5 h)淬火+(-196℃×3,6,12 h)深冷处理+(560℃×2 h)三次回火处理,通过销盘摩擦磨损试验研究了深冷处理工艺参数对其高温耐磨性的影响。通过XRD获得不同热处理工艺下的衍射图谱,并通过X射线线形分析法研... 详细信息

对Cr7V模具钢进行了(1030℃×0. 5 h)淬火+(-196℃×3,6,12 h)深冷处理+(560℃×2 h)三次回火处理,通过销盘摩擦磨损试验研究了深冷处理工艺参数对其高温耐磨性的影响。通过XRD获得不同热处理工艺下的衍射图谱,并通过X射线线形分析法研究深冷处理不同工艺参数对Cr7V模具钢位错密度的影响。结果表明:深冷处理对Cr7V模具钢高温耐磨性和位错密度的影响规律一致,随保温时间的延长,高温耐磨性和位错密度的提升程度均呈现先升后降的趋势,其中深冷保温6 h后试样磨损量为87. 6 mg,位错密度为1. 4295×10^(16)m^(-2),表现出最好的性能,其高温耐磨性较未深冷处理试样提高了53%,位错密度提高约28%。

关键词：深冷处理耐磨性位错密度 XRD Cr7V模具钢

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药用植物丛枝菌根研究进展

中草药 2009年第1期40卷 156-160页

作者：程俐陶刘作易郭巧生朱国胜南京农业大学中药材研究所江苏南京210095 贵州省农业科学院生物技术重点实验室贵州贵阳550006

进入21世纪以来,随着现代科技发展和研究水平不断提高,发现药用植物丛枝菌根(AM)真菌与其寄主植物有着紧密关系,表现在可促进寄主植物生长发育、提高抗性、影响次生代谢产物积累等方面,人们开始高度重视药用植物的作用,并开展了相关领... 详细信息

进入21世纪以来,随着现代科技发展和研究水平不断提高,发现药用植物丛枝菌根(AM)真菌与其寄主植物有着紧密关系,表现在可促进寄主植物生长发育、提高抗性、影响次生代谢产物积累等方面,人们开始高度重视药用植物的作用,并开展了相关领域的研究工作。将AM真菌做成菌剂使用,是提高栽培药用植物产量及质量、稳定药效与药源的新方法之一。着重介绍国内外药用植物AM真菌种类多样性、形态解剖特点、AM真菌的效应及其机制等方面的进展。

关键词：药用植物从枝菌根半夏

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退火温度对硅基GaN薄膜质量的影响

固体电子学研究与进展 2007年第4期27卷 472-475页

作者：吴玉新薛成山庄惠照田德恒刘亦安何建廷艾玉杰孙莉莉王福学山东师范大学半导体研究所

采用电泳沉积法在Si(111)衬底上制备GaN薄膜,并研究退火温度对GaN薄膜晶体质量、表面形貌和发光特性的影响。傅立叶红外吸收谱(FTIR)、X射线衍射(XRD)和扫描电镜(SEM)的测试结果表明所得样品为六方纤锌矿结构的GaN多晶薄膜,随退火温度... 详细信息

采用电泳沉积法在Si(111)衬底上制备GaN薄膜,并研究退火温度对GaN薄膜晶体质量、表面形貌和发光特性的影响。傅立叶红外吸收谱(FTIR)、X射线衍射(XRD)和扫描电镜(SEM)的测试结果表明所得样品为六方纤锌矿结构的GaN多晶薄膜,随退火温度的升高,晶粒尺寸增大,结晶化程度提高。室温下光致发光谱的测试发现了位于367 nm处的强发光峰和437 nm处的弱发光峰,其发光强度随退火温度的升高而增强,但发光峰的位置并不发生移动。

关键词：氮化镓薄膜电泳沉积退火温度光致发光

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基于增材制造的设计理论和方法研究现状

新技术新工艺 2017年第10期 31-35页

作者：王震巩维艳祁俊峰陈怡刘婷婷北京卫星制造厂北京100094

介绍了增材制造(3D打印)的概念和特点,并结合该技术的发展背景,从增材制造设计理念的形成、增材制造设计的基础晶胞单元结构研究和增材制造拓扑优化设计分析软件及应用等3个主要研究领域,详细介绍了基于增材制造的设计技术在国内外的发... 详细信息

介绍了增材制造(3D打印)的概念和特点,并结合该技术的发展背景,从增材制造设计理念的形成、增材制造设计的基础晶胞单元结构研究和增材制造拓扑优化设计分析软件及应用等3个主要研究领域,详细介绍了基于增材制造的设计技术在国内外的发展现状及趋势,并结合我国航空航天产品的结构特点和发展趋势,对基于增材制造设计的研究方向提出了几点建议。

关键词：增材制造 3D打印设计结构

Relativistic transformation between τ and TCG for Mars missions under iau Resolutions

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Research in Astronomy and Astrophysics 2014年第2期14卷 233-240页

作者： Jun-Yang Pan yi Xie Department of Astronomy Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of Education

Considering the fact that the general theory of relativity has become an in- extricable part of deep space missions, we investigate the relativistic transformation between the proper time of an onboard clock τ and the Geocentric Coordinate Time （TCG） for Mars missions. By connecting τ with this local timescale associated with the Earth, we extend previous works which focus on the transformation between τ and the Barycentric Coordinate Time （TCB）. （TCB is the global coordinate time for the whole solar system.） For practical convenience, the relation between τ and TCG is recast to directly depend on quantities which can be read from ephemerides. We find that the difference between τ and TCG can reach the level of about 0.2 seconds in a year. To distinguish various sources in the transformation, we numerically calculate the contributions caused by the Sun, eight planets, three large asteroids and the space- craft. It is found that if the threshold of 1 microsecond is adopted, this transformation must include effects due to the Sun, Venus, the Moon, Mars, Jupiter, Saturn and the velocities of the spacecraft and Earth.

关键词： reference systems -- time -- method: numerical -- space vehicles

Relativistic algorithm for time transfer in Mars missions under iau Resolutions: an analytic approach

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Research in Astronomy and Astrophysics 2015年第2期15卷 281-292页

作者： Jun-Yang Pan yi Xie School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education

With tremendous advances in modem techniques, Einstein＇s general rela- tivity has become an inevitable part of deep space missions. We investigate the rela- tivistic algorithm for time transfer between the proper time - of the onboard clock and the Geocentric Coordinate Time, which extends some previous works by including the effects of propagation of electromagnetic signals. In order to evaluate the implicit algebraic equations and integrals in the model, we take an analytic approach to work out their approximate values. This analytic model might be used in an onboard com- puter because of its limited capability to perform calculations. Taking an orbiter like yinghuo-1 as an example, we find that the contributions of the Sun, the ground station and the spacecraft dominate the outcomes of the relativistic corrections to the model.

关键词： reference systems—time—method:analytical—space vehicles

Relativistic time transfer for a Mars lander:from proper time to Areocentric Coordinate Time

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Research in Astronomy and Astrophysics 2016年第10期16卷 45-54页

作者： De-Wang Xu Qing-Shan Yu yi Xie School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Shanghai Key Laboratory of Space Navigation and Position Techniques Shanghai 200030China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of EducationNanjing 210093China

As the first step in relativistic time transfer for a Mars lander from its proper time to the time scale at the ground station, we investigate the transformation between proper time and Areocentric Coordinate Time （TCA） in the framework of iau Resolutions. TCA is a local time scale for Mars, which is analogous to the Geocentric Coordinate Time （TCG） for Earth. This transformation contains two contributions： inter- hal and external. The internal contribution comes from the gravitational potential and the rotation of Mars. The external contribution is due to the gravitational fields of other bodies （except Mars） in the Solar System. When the （in）stability of an onboard clock is assumed to be at the level of 10-13, we find that the internal contribution is dominated by the gravitational potential of spherical Mars with necessary corrections asso- ciated with the height of the lander on the areoid, the dynamic form factor of Mars, the flattening of the areoid and the spin rate of Mars. For the external contribution, we find the gravitational effects from other bodies in the Solar System can be safely neglected in this case after calculating their maximum values.

关键词： reference systems -- time -- space vehicles

Relativistic transformations between global and local velocities of an orbiter under iau Resolutions

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Research in Astronomy and Astrophysics 2014年第10期14卷 1343-1350页

作者： Zong-Shui Yang yi-Chen Han Jing-Hao Liu Song-He Qin Zhen Wan Xiao-Yu Wang Ze-Hao Zhong Kai Zhu yi Xie School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of Education

Einstein＇s general relativity （GR） has become an inevitable part of deep space missions. According to the International Astronomical Union （iau） Resolutions which are built in the framework of GR, several time scales and reference systems are recommended to be used in the solar system for control, navigation and scientific op- eration of a spacecraft. Under the iau Resolutions, we derive the transformations be- tween global and local velocities of an arbitrary orbiter. These transformations might be used in orbit determination with Doppler tracking and prediction of Doppler ob- servables for the spacecraft. Taking the yingHuo-1 Mission as a technical example of future Chinese Mars explorations, we evaluate the significance and contributions of various components in the transformations. The largest contribution of the relativistic parts in the transformations can reach the level of ～ 5 × 10-5 m s^-1. This suggests that, for such a spacecraft like we have assumed, if the accuracy of Doppler tracking is better than ～ 5 × 10-5 m s^-1 then the relativistic parts of the transformations of velocities will be required.

关键词： reference systems -- method numerical-- space vehicles -- techniques radial velocities

Effects of 24h ultra-marathon on biochemical and hematological parameters

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World Journal of Gastroenterology 2004年第18期10卷 2711-2714页

作者： Huey-JuneWu Kung-TungChen Bing-WuShee Huan-ChengChang yi-JenHuang Rong-SenYang DepartmentofPhysicalEducation ChineseCultureUniversityTaipei111TaiwanChina DepartmentofGenenalEducation MingHsinUniversityofScienceandTechnologyHsin-chu304TaiwanChina Li-shinhospitalPingjenCity TaoyuanCountyTaiwanChina DepartmentofPhysicalEducation SoochowUniversityTaipeil12TaiwanChina DepartmentofOrthopaedics CollegeofMedicineNationalTaiwanUniversity&HospitalTaipei10043TaiwanChina

AIM: To analyze detailed changes in hematology and biochemistry tests parameters before and after a longdistance race in ultramarathon ***: Blood samples of 11 participants were obtained for standard analysis before, immediately after, two days after and nine days after the 2002 International Ultramarathon 24 h Race and the International Association of Ultrarunners (iau) Asia 24 h ***: Total bilirubin (BIL-T), direct bilirubin (BIL-D),alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) increased statistically significantly(P<0.05) the race. Significant declines (P<0.05) in red blood cell (RBC), hemoglobin (Hb) and hematocrit (Hct)were detected two days and nine days d after the race.2 d after the race, total protein (TP), concentration of albumin and globulin decreased significantly. While BIL, BIL-D and ALP recovered to their original levels. High-density lipoprotein cholesterol (HDL-C) remained unchanged immediately after the race, but it was significantly decreased on the second and ninth days after the ***: Ultra-marathon running is associated with a wide range of significant changes in hematological parameters, several of which are injury related. To provide appropriate health care and intervention, the man who receives athletes on high frequent training program high intensity training programs must monitor their liver and gallbladder function.

关键词： 24h 过激耐力生物化学血液学参数长跑