离子束辅助淀积低温微光学元件红外宽带增透膜

简要叙述了锗基片微光学元件红外宽带减反膜的设计与制作。着重介绍了离子束辅助淀积制备该膜系的过程，给出了用该方法制作８～１２μｍ波段的减反膜的测试曲线，它具有峰值透过率高，在设计波长范围内的平均透过率大于９７％以上，膜层附着好，可以切割和擦洗，可以在室温和１００Ｋ低温下反复循环使用。     

双短脉冲驱动类镍钐X光激光的模拟

 介绍了模拟产生类镍离子电子碰撞激发X光激光全过程的系列程序。利用它模拟了英国RAL实验室的双短脉冲驱动类镍钐X光激光实验。与实验结果进行了比较。还研究了不同弯曲度的靶及驱动激光功率密度不均匀性对输出激光强度的影响。对驱动激光的脉宽、主脉冲的功率密度以及主脉冲的延迟时间等进行了优化设计。     

Pulsed-Field-Gradient Measurements of Time-Dependent Gas Diffusion

Pulsed-field-gradient NMR techniques are demonstrated for measurements of time-dependent gas diffusion. The standard PGSE technique and variants, applied to a free gas mixture of thermally polarized xenon and O₂, are found to provide a reproducible measure of the xenon diffusion coefficient (5.71 × 10⁻⁶m²s⁻¹for 1 atm of pure xenon), in excellent agreement with previous, non-NMR measurements. The utility of pulsed-field-gradient NMR techniques is demonstrated by the first measurement of time-dependent (i.e., restricted) gas diffusion inside a porous medium (a random pack of glass beads), with results that agree well with theory. Two modified NMR pulse sequences derived from the PGSE technique (named the Pulsed Gradient Echo, or PGE, and the Pulsed Gradient Multiple Spin Echo, or PGMSE) are also applied to measurements of time dependent diffusion of laser polarized xenon gas, with results in good agreement with previous measurements on thermally polarized gas. The PGMSE technique is found to be superior to the PGE method, and to standard PGSE techniques and variants, for efficiently measuring laser polarized noble gas diffusion over a wide range of diffusion times.     

制备工艺对电子俘获材料性能的影响

利用等离子体质谱(ICP-MS)技术测试了硫化助熔剂法和稀土直接掺杂工艺合成电子俘获材料的化学计量比,结果表明,采用稀土直接掺杂工艺合成材料的化学计量比更接近设计值;通过分析电子俘获材料的发光机制和光谱测试结果,讨论了制备工艺条件对电子俘获材料中稀土离子化合价的影响.     

New Silver Halide Sensitized Gelatin Material: Its Processing

ＮｅｗＳｉｌｖｅｒＨａｌｉｄｅＳｅｎｓｉｔｉｚｅｄＧｅｌａｔｉｎＭａｔｅｒｉａｌ：ＩｔｓＰｒｏｃｅｓｉｎｇＰＡＮＧＬｉｎ１ＧＵＯＬｕｒｏｎｇ１ＺＨＡＮＧＷｅｉｐｉｎｇ２ＴＡＮＧＪｉｙｕｅ１ＷＡＮＧＫｅｔａｉ１（１ＩｎｆｏｒｍａｔｉｏｎＯｐｔｉｃｓＩ...     

Growth and structural characterization of semiconducting Ru2Si3

Recent band structure calculations indicate that ruthenium silicide (Ru₂Si₃) is semiconducting with a direct band gap. Electrical measurements lead to a band gap around 0.8 eV which is technologically important for fiber communications. This makes Ru₂Si₃ a promising candidate for silicon based optical devices, namely LEDs. We present first results on the epitaxial growth of ruthenium silicide films on Si(1 0 0) and Si(1 1 1) fabricated by the template method, a special molecular beam epitaxy technique. Orientational relationships on Si(1 1 1) have been determined. We characterized the films by Rutherford Backscattering and Channeling, X-ray diffraction and transmission electron microscopy.     

Near-field optical imaging using force detection with new tip-electrode geometry

We propose a new tip-electrode geometry to detect an (optical) evanescent field using noncontact atomic force microscopy. Using a semi-transparent metal electrode on the prism surface, the force sensitivity due to evanescent field in new tip-electrode geometry was enhanced by a factor of about 1000, comparing with that in old tip-electrode geometry where electrode was located behind the prism. Furthermore, this tip-electrode geometry avoids the electrostatic field caused by the residual charges and contact-electrified charges near the prism surface, which affects the force sensitivity due to evanescent field. We demonstrated the high resolution imaging of the evanescent field on the Au film with 15-nm (λ/33) lateral resolution.     

AlGaN薄膜的微区Raman散射光谱研究

利用微区Ｒａｍａｎ散射技术,对低压ＭＯＣＶＤ生长的不同Ａｌ组分的ＡｌｘＧａ１－ｘＮ薄膜（ｘ＝０,０．０７,０．１５）进行了背散射Ｚ（Ｘ,Ｘ）Ｚ－几何配制下的测量．Ａ１（ＬＯ）模式的声子频移随Ａｌ组分的变化关系为：ω（ＡｌｘＧａ１－ｘＮ）＝（１＋０．２２０ｘ）ω（ＧａＮ）．观察到了Ａ１（ＬＯ）模式由于空间相关效应引起的展宽．Ｅ２模式随Ａｌ组分的的增大产生的移动很微小,但趋于展宽．这被认为是Ｅ２模式的声子频移随Ａｌ组分的增加而增大与其受到的张应力导致的声子频移随Ａｌ组分的增加而减小共同作用的结果．在多种配置下,观察到了Ａｌ０．０７Ｇａ０．９３Ｎ薄膜的Ａ１（ＴＯ）模式、Ａ１（ＬＯ）模式、Ｅ１（ＴＯ）模式和Ｅ２模式．验证了ＡｌｘＧａ１－ｘＮ薄膜的Ｒａｍａｎ选择定则．表明ＡｌｘＧａ１－ｘＮ薄膜具有单模行为．     

Field of a Point Source Within Perfectly Conducting Parallel-Plates in a Homogeneous Biisotropic Medium

The spherical wave scattering response by a perfectly conducting open–ended waveguide in a biisotropic medium is obtained. Interestingly, the vector diffraction problem is reduced to the scattering of a single scalar field, this scalar field being the normal component of either a left–handed or a right–handed Beltrami field. Here, we explicitly consider the scattering of the left–handed field component, that of the other scalar field being analogously tractable. The solution is constructed with the aid of the Wiener–Hopf technique.     

FD-21风洞Ma=10高超声速推进试验技术探索

针对Mach数8以上（Ma>8）冲压发动机地面试验能力不足问题,基于FD-21高能脉冲风洞,开展了吸气式推进试验技术探索,提升了FD-21风洞的重活塞驱动能力,获得了总压18.66 MPa、总温3 950 K、Ma=9.62、静压436.6 Pa、速度3 km/s的高焓大动压模拟流场,同时发展了高时间分辨率吸收光谱测量技术和基于重模型自由飞原理的发动机推阻测量方法.在此基础上,设计了弯曲激波压缩二元发动机,构建了燃料在线供应与喷注控制、模型悬挂与瞬态释放及相关测量一体的试验系统,在所建立的Ma=9.62风洞模拟环境中进行了集成验证试验,定量测得了有/无氢气射流与空气/氮气超声速气流作用下二元发动机的壁面压力、吸收光谱峰值吸收率、轴向力等数据,并利用纹影观测到了进气道唇口与燃烧室部位的波系特征.多次试验所得的壁面压力、峰值吸收率、轴向力随时间变化曲线均存在2 ms以上的平台,表明二元发动机建立了准定常流动.冷热态及氮气对照组对应的壁面压力分布、峰值吸收率、轴向力等数据呈现出了明显不同,且二者规律近似一致,一方面说明所建立的模拟流场、燃烧诊断技术、发动机推阻测量技术是有效的,另一方面也表明二元发动机实现了点火燃烧、获得有效热功转换,为后续相关研究奠定了良好的基础.