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1.
用SIMOX(Separationby Implanted Oxygen,即氧注入隔离)技术制备SOI-CMOS用的SOI(Silicon OnInsu lator,即绝缘体上长单晶硅膜)样品;对SOI样品红外吸收光谱的分析,从而计算了SOI结构材料中SiO2埋层的厚度;测试样品不同点的红外吸收光谱,可考察样品SiO2埋层厚度的不均匀性,据此,并可分析与之相关的SOI样品的质量参数.这种分析方法,是一种无损的检测手段,具有实用价值.  相似文献   

2.
研究SOI-SIMOX(Silicon On Insulation-Separation by Implanted Oxygen)材料及SIMOX-CMOS器件.高能大剂量(170keV,1.5×1018/cm2)氧离子注入到P型(100)单晶Si衬底,再经高温长时间(1300℃,6h)退火,形成SIMOX结构材料.经测试,SIMOX表层单晶硅膜反型为N型,研究表明,这是由于在制备SIMOX的工艺中,残留在SIMOX表层硅膜内的氧离子起施主作用所致,并计算出氧杂质在硅中的施主电离能,其值为0.15eV.采用SIMOX材料研制了MOSFET及CMOS三3输入端与非门电路,并介绍了研制SIMOX-CMOS器件的主要工艺.  相似文献   

3.
美国“地球观测系统”卫星参数见表1。表1 “地球观测系统”参数表卫星EOS-AMEOS-PMEOS-COLOREOS-AEROEOS-ALTEOS-CHEM科学用途测量地表、云、气溶胶和辐射收支特性测量云、降水和辐射收支、地面雪和海冰、海面温度和海洋生产率研究海洋生物量和生产率观测大气和气溶胶测量海平面高度、洋流和冰层质量测量大气化学成分及其传输过程、海洋现象有效载荷ASTER,CERES,MODIS,MISR,MOPITTAIRS/AMSU/MHS,MODIS,CERES,MIMRSeaWIF…  相似文献   

4.
介绍了晶体振荡器在国内外的广泛应用和MCXO晶振的原理方案及其较之TCXO晶振的各种优越性。MCXO晶体振荡器结合了SC切等特殊晶体的特性及微型计算机技术,对晶体振荡器和高准确度频率源的长远发展有重要意义。  相似文献   

5.
杨照德 《国际太空》1994,(2):26-28,32
从轨道上向地面自由地发送、接收宽频带图像信号的光通信系统已十分引人注目。而卫星间光通信(OISL)将是人类在大气层外或在卫星轨道上支持多种活动的基础。美国、欧洲、日本都在长期进行OISL技术的开发,现将研究状况及未来动向概述如下:1.美国以航宇局(NASA)、马萨诸塞工业大学(MIT)等为中心进行OISL的研究。喷气推进实验室(JPL)主要目标是从事深空通信应用方面的研究。①NASANASA的哥达德空间飞行中心(GSFC)正进行有关强度调制/直接检波(IM/DD)方式为主体的OISL研究。按照传…  相似文献   

6.
介绍了第二届亚洲计算机视觉会议(SECOND ASIAN CONFER-ENCE ON COMPUTER VISION,ACCV’95)的一些情况;回顾了在该领域及相关学科的研究成果,讨论了当前计算机视觉所面临的理论与实际应用问题,并对中国空间技术研究院这一学科的发展提出看法。  相似文献   

7.
空间扫描     
科学家们争抢使用红外观测平台(ISO)1000名科学家就欧空局的ISO使用时间分配问题提出2500多条建议。ISO定于1995年9月发射。俄罗斯批准建立低地轨道卫星系统将建立一个由36颗小卫星组成的低地轨道星座,进行电视图像传输。马来西亚第一颗国家卫星Measat将于1995年升空它由阿里安-4火箭发射,是休斯公司造的HS-376型卫星,重量不到1400千克,能为马来西亚、菲律宾和印度南部提供电信和直播电视业务。美商业部第一次将出口许可证发给用俄罗斯火箭发射的美国卫星该星是美国基尔特兰空军基地菲…  相似文献   

8.
研究了在紫铜基材上用离子束增强沉积法(IBED)沉积TiB2薄膜后,在600,700和800℃的空气中氧化的动力学曲线;在INH2SO4溶液中,用动电位扫描法测定了其极化曲线和极化阻力,用SEM观察了其形貌,用俄歇电子谱仪(AES)分析了膜的成份,用X-射线衍射仪(XRD)研究了膜的微观结构;讨论了TiB2薄膜具有优良耐蚀性的机理。  相似文献   

9.
日本宇宙开发事业团就有关预定于1994年7月进行的第2次国际微重力实验室(IML-2)的计划内容以及准备情况概述如下。1.IML-2计划概要IML-2计划是以美航宇局(NASA)为中心,通过国际合作实施的空间实验计划。由参加的各国将各自准备的实验装置,搭载在哥伦比亚号航天飞机的空间实验室上,利用微重力环境进行各种生命科学和材料科学实验。(1)推动计划的办事处:NASA生命、材料科学应用局(OLMSA)(2)计划实施综合中心:NASA马歇尔空间飞行中心(MSFC)(3)任务梗概:任务时间 13天(…  相似文献   

10.
介绍了第二届亚洲计算机视觉会议(SECONDASIANCONFERENCEONCOMPUTERVISION,ACCV’95)的一些情况;回顾了在该领域及相关学科的研究成果;讨论了当前计算机视觉所面临的理论与实际应用问题,并对中国空间技术研究院这一学科的发展提出看法。  相似文献   

11.
神舟飞船生长GaMnSb材料过程及性能分析   总被引:1,自引:0,他引:1  
利用神舟3号飞船(SZ-3)上的多样品空间晶体炉制备出GaMnSb材料.所设计的石英安瓿使用氧化铝棉毡和特殊设计制造的氮化硼坩锅进行减震,经受住了严峻的力学环境的考验,完成了材料的空间生长实验,达到了空间生长材料的初步要求.对空间生长的GaMnSb晶体进行了X射线能谱分析和X射线衍射分析,发现空间生长的GaMnSb是多晶结构.对未获得GaMnSb单晶的原因进行了分析,发现空间晶体炉温度的波动和提供能量的不足是导致生成GaMnSb多晶结构的主要原因.由于在晶体生长的初始阶段晶体炉提供的能量不足,使GaSb单晶部分未能熔化,从而导致GaMnSb材料的生长在没有籽晶的情况下进行.  相似文献   

12.
We address the problem of interacting relativistic current sheets in self-consistent kinetic plasma simulations within the framework of the Particle-In-Cell model. The interaction is enforced in head-on collisions of up to 10 current sheets at relativistic bulk speeds. The simulations are motivated by the general problem of Poynting flux dissipation in ‘striped wind’ configurations presumably governing the relativistic outflows pervasive in pulsar winds and gamma-ray bursts. We identify the generation of non-thermal particles and formation of a stable power-law shape in the particle energy distributions f(γ) dγ ∝ γs dγ. In 1D, a spectral index s ∼ 2 is observed and attributed to a stochastic Fermi-type acceleration mechanism. In 2D, the generic index of s ∼ 3–4 is retained as in previous simulations of individual current sheets. Whereas in 2D the high energy cut-off is constrained by the limited dissipation of magnetic energy, in 1D the process converts the bulk motion of current sheets towards directed particle momentum of an exclusive class of non-thermal particles.  相似文献   

13.
Various aerial platforms intended for long endurance survey of the Titan surface are presented. A few novel concepts are introduced, including a heated methane balloon and a balloon with a tethered wind turbine. All the concept options are predicted to have lower scientific payload fractions than the Huygens probe. It is concluded that the selection of the best aerial platform option depends on more accurate mass estimates and a clear decision on whether, or not, in situ surface composition measurements are required in conjunction with aerial remote sensing.  相似文献   

14.
To understand the evolution of organic molecules involved in extraterrestrial environments and with exobiological implications, many experimental programs in the laboratory are devoted to photochemical studies in the gaseous phase as well as in the solid state. The validity of such studies and their applications to extraterrestrial environments can be questioned as long as experiments conducted in space conditions, with the full solar spectrum, especially in the short wavelength domain, have not been implemented. The experiments that are described here will be carried out on a FOTON capsule, using the BIOPAN facility, and on the International Space Station, using the EXPOSE facility. Vented and sealed exposition cells will be used, which will allow us to study the chemical evolution in the gaseous phase as well as heterogeneous processes, such as the degradation of solid compounds and the release of gaseous fragments.  相似文献   

15.
基于LuGre模型的电液加载系统摩擦补偿   总被引:4,自引:2,他引:2  
为了提高电液加载系统控制精度,针对摩擦问题提出了基于LuGre摩擦模型的前馈补偿方法.建立了用于摩擦仿真分析和补偿器设计的电液加载系统数学模型;通过实验获取并分析了相关的摩擦数据;基于实验数据进行LuGre模型参数辨识,把LuGre模型和辨识结果引入电液加载系统数学模型,并进行仿真结果与实际摩擦数据的对照,证明了LuGre摩擦模型的准确性.设计前馈补偿器,进行了实验对比,实验结果表明前馈补偿器可将摩擦产生的控制误差有效地降至未补偿时的30%左右.   相似文献   

16.
The space-borne observatories CoRoT (Convection Rotation and planetary Transits) and Kepler have provided photometric time series data of unprecedented precision for large numbers of stars. These data have revolutionized the fields of transiting exoplanets and asteroseismology. In this review some important asteroseismic results obtained using data from the CoRoT and Kepler space missions concerning stars that show solar-like oscillations are discussed. These results comprise, among others, measurements of the location of the base of the convection zone and helium second-ionization zone in main-sequence stars, the presence (or not) of core-helium burning in red-giant stars, as well as differential rotation in these stars.  相似文献   

17.
The ESA scientific programme has, so far, provided several significant astrophysics experiments and further important missions are scheduled for execution during the next decade. These missions are briefly summarised together with several astrophysics investigations presently under study.  相似文献   

18.
Heliophysics is a new research field that explores the Sun–Solar System Connection; it requires the joint exploitation of solar, heliospheric, magnetospheric and ionospheric observations.  相似文献   

19.
In this report the main results of the study of radioactivity of the solar sistem bodies are considered. The radioactivity of the Moon and planets was measured by means of vehicles in situ. The radioactivity of the lunar samples, brought to the Earth was studied with laboratory equipment.  相似文献   

20.
一种提高螺栓联接强度的新方法   总被引:2,自引:0,他引:2  
根据山本晃教授对螺栓,螺母,螺纹牙受力及其变形研究的成果,导出了该理论条件下受拉螺栓在等载荷受力状态下,当螺栓螺纹采用标准尺寸,螺母螺纹的螺旋线形状,并依据实用性,从螺母螺纹加工方便考虑,提出了近似等负荷螺纹。  相似文献   

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