C－BN衬底上金刚石的异质外延生长研究

用热灯丝ＣＶＤ方法在Ｃ－ＢＮ单晶衬底上制备出金刚石膜，并且在Ｃ－ＢＮ（１００）面上观察到金刚石的异质外延。     

Crack Branching in All-Oxide Ceramic Composites

The existence of oxidation embrittlement in previously developed ceramic-matrix composite (CMC) systems at intermediate temperatures (500–900°C) has motivated the development of all-oxide CMCs. Studies of the damage tolerance of an all-oxide CMC suggest that it relies on distributing fiber bundles heterogeneously in a porous matrix with a thin matrix-only region surrounding each bundle. For such composites, loading in the direction of the fibers causes cracks to first commence in the fiber bundles, breaching both the matrix and fibers within each bundle. These fiber-bundle cracks then branch in the matrix-rich region, parallel to the load, forming stable H-shaped cracks. The mechanics behind one mechanism controlling the competition between branching and continued extension of a preexistent fiber-bundle crack in a unidirectional all-oxide CMC are provided in this paper. Both plane-strain and axisymmetric cases are studied using an integral equation method as well as a numerical method based on finite elements. With no elastic mismatch assumed between the fiber and matrix, a single nondimensional combination, E Ω/σ_∞, emerges as the key parameter that governs the tendency of the crack to branch (where E is Young's modulus, Ω is the thermal misfit strain between the fiber bundle and matrix, and σ_∞ is the stress applied parallel to the fiber axis). Quantitative estimates of the conditions under which the branching of the bundle crack is favored are presented.     

Direct imaging of a high-power diode laser cavity using a transparent indium-tin-oxide (ITO) contact

We describe a novel "see-through" indium-tin-oxide contact on the n-side of a high power unstable resonator semiconductor laser (URSL) that allows direct observation of the cavity during high power operation. Under optimized annealing conditions this transparent ITO contact has a low enough specific contact resistivity to permit normal high power CW operation of the URSL and allows the observation of filamentation. This contact scheme is applicable to a wide range of semiconductor lasers and is especially appropriate for high power devices. The same structure can also be used to obtain a 2-D thermal map of the laser cavity.     

Effects of oxide additives on sheet resistance of W thick-film conductor

A multilayer AIN-W cofired body has been developed using the pressless sintering technique. Effects of additives, such as Y₂O₃, CaO, La₂O₃, MgO, Al₂O₃ and SiO₂, on the sheet resistance of W conductor were studied. The sheet resistance of the W conductor increases with increasing additives in the W paste. However, the oxides can be divided into two groups. The effect of the first group on sheet resistance is different from that of the second group.     

PTCR热敏电阻新原料的探讨EI

研究了以工业生产中间产物偏钛酸为原料生产ＰＴＣＲ（正温度系数热敏电阻）的一些问题。其中主要包括偏钛酸作为生产ＰＴＣＲ热敏电阻原料的适宜煅烧温度、原材料的预磨情况等对合成瓷料性能的影响。结果表明：瓷料半导化的条件与偏钛酸的煅烧温度及原料预磨情况密切相关。低于８００℃的一定温度范围内预先对偏钛酸球磨后煅烧或８００℃以上直接煅烧，均可实现瓷料的半导化。     

用光相关光谱研究乳液粒度的浓度依赖性

利用光相关光谱测定了不同浓度的聚丙烯酸酯核／壳乳液和聚苯乙烯标样乳液在室温下的粒度，确定了两体系可测粒度的浓度范围，随粒度多分散性增加，可测粒度的浓度范围减小，且浓度范围与试样粒度有关。测定结果进一步表明，随测定试样的浓度增加，粒度下降，根据Ｓｔｏｋｅｓ－Ｅｉｎｓｔｅｉｎ公式，求出了粒子移动扩散系数，以及浓度为零时的粒子移动扩散系数。     

三脉冲不等强度激光片光源的研制及应用

本文报道了最近研制成功三脉冲不等强度调Q红宝石激光片光源系统.利用小颗粒对片光源90°方向的散射光对动态颗粒场进行高速摄影,从底片中能够精确直观地判断微小颗粒的瞬时分布、运动方向、速度和加速度情况.     

用PSD检测长直导轨准直度

介绍了用光电位置传感器（ＰＳＤ）检测长直导轨的原理和方法。利用ＰＳＤ作为位置传感的检测系统能实时、连续地对被测件三维空间准直度进行检测，更好地解决了以往移动桥板分段测量、人工读数（数格）局部检测的方法存在的问题。     

低温下液体饱和蒸气压的测试

着重介绍了静态法测试低温下（－１００～５０℃）液体饱和蒸气压的原理及方法，给出了低温下液体全氟三乙胺饱和蒸气压的测试结果，并进行了讨论。