Preparation of Pb(Zr0.52Ti484848)O3 thin films on silicon-on-insulator substrates by excimer laser deposition combined with rapid thermal annealing

In this paper we report the fabrication of ferroelectric Pb(Zr_0.52Ti_0.48)O₃ (PZT) thin films on Si-on-Insulator (SOI) substrates with and without an electrode by pulsed excimer laser deposition combined with rapid thermal annealing. Based on the structural and interfacial characteristics analysis by X-ray diffraction (XRD), Rutherford backscattering spectroscopy (RBS), cross-sectional transmission electron microscopy (XTEM) and automatic spreading resistance measurement (ASR), the film structure and orientation were revealed to be dependent on the annealing time and annealing temperature as well as deposition temperature. From RBS spectra and XTEM observation it is shown that the PZT thin films did not interact with the top silicon layers of SOI and that the composition of the film was similar to the target. The ASR measurements showed that the electrical properties of PZT/SOI as well as PZT/Pt/SOI were abrupt, and that the electrical properties of the SOI substrates were still good after the PZT growth.     

Non-steady-state model for kinetics of free radical polymerization, 4. Direct thermal initiation

This paper deals with the non-steady-state kinetics of direct thermal initiated polymerization. The initiation is assumed to be a bimolecular reaction of the monomer. The relationship between the radical concentration and the monomer conversion is rigorously derived. In further treatment a few very close approximations are introduced based on the fact that the number of monomer molecules reacting in the initiation step is much less than that consumed in the propagation step for a process producing high polymer, and the value of the rate constant for propagation or chain transfer is much lower than that for chain termination. Expressions for various molecular parameters, such as molecular weight distribution, number-average and weight-average degrees of polymerization, and dispersity, are given. Several numerical examples are provided.     

光纤模式噪声的研究

综述了光纤模式噪声的产生、计算，并介绍了减小它的一些方法。     

Tandem repeating of the expression cartridge--a novel strategy to enhance the expression efficiency of cloned gene in Escherichia coli

The aim of this study was to determine the actual prevalence of diabetes mellitus and to investigate the contribution of various risk factors to the diabetes mellitus among the population in a methyl mercury polluted area. The study was a population based cross sectional mass screening survey. A case-control study was designed to estimate the role of various risk factors including methyl mercury exposure for diabetes mellitus. The study was confined to a small rural town 10 km north of Minamata City; 1,087 persons older than 40 years were examined. Measurement of glucose metabolism was made on the basis of urine and haematological examinations. Data on risk factors were collected by questionnaire, and by measurement of body height and weight (obesity). The prevalence rate of the diabetes mellitus was 8.4% in males and 5.3% in females. The odds ratio of family history was significantly higher, 4.63. The odds ratio of residential history in a methyl mercury high polluted area was 0.58. The prevalence of the diabetes mellitus in this methyl mercury polluted area was not increased, contrary to what was expected based on the pathological findings.     

连续输出20WAlGaAs／GaAs量子阱激光二极管线列阵

采用ＭＯＣＶＤ实现了ＡｌＧａＡｓ／ＧａＡｓ量子阱结构，获得了连续输出２０Ｗ激光二极管线列阵，线列阵长度１．０ｃｍ，激射波长８０８±４ｎｍ。     

GaN的MOVPE生长和m－i－n型蓝光LED的试制

利用自行研制的常压ＭＯＶＰＥ设备和全部国产ＭＯ源，采用低温生长缓冲层技术，在蓝宝石（α－Ａｌ２Ｏ３）衬底上获得了高质量的ＧａＮ外延层。未掺杂的ＧａＮ外延层的室温电子迁移率已达１１４ｃｍ２／Ｖ．ｓ，载流于浓度为２×１０１８。７７Ｋ光致发光谱近带边发射峰波长为３６５ｎｍ，其线宽为４ＤｍｅＶ。Ｘ射线双晶衍射回摆曲线的线宽为３６０ａｒｃｓｅｃ。用Ｚｎ掺杂生长了绝缘的ｉ－ＧａＮ层。在此基础上研制了ｍ－ｉ－ｎ型ＧａＮ的ＬＥＤ，并在室温正向偏压下发出波长为４５５ｎｍ的蓝光。     

Teflon－AF~R──新一代的电子和光电功能聚合物材料

ＴｅｆｌｏｎＡＦ是新一代高性能的Ｔｅｆｌｏｎ氟碳树脂。完全非晶态的ＴｅｆｌｏｎＡＦ具有许多突出优点，如在１９０ｎｍ厚度内的完全透明度，低折射率（１．２９～１．３１）；突出的介电性能（在塑料家族中具有最低的介电常数）；良好的力学性能；宽温区的热性能和优良的化学惰性及在选定的全氟化溶剂内受限制的溶解性等等。ＴｅｆｌｏｎＡＦ在高科技领域中具有广泛的应用前景。如用作在光纤和集成光学方面的重要材料，半导体和工艺材料，介电和释放材料，特殊性能的化学和工业材料以及生物医学材料等。     

神经网络离散变结构控制的算法及其应用

本文首次将自适应线性神经元（Ａｄａｌｉｎｅ）用于离散变结构控制。以滑模面Ｓ（ｋ）＝０作为Ａｄａｌｉｎｅ元的希望输出，作为Ａｄａｌｉｎｅ元的实际输出，通过ＬＭＳ算法在线调整权值可保证滑态可达条件的满足。应用所提出的控制策略对泵控马达速度伺服系统进行控制，仿真表明控制效果是令人满意的。     

Agreement between a frequency-weighted filter for continuous biomechanical measurements of repetitive wrist flexion against a load and published psychophysical data

A previous pilot study demonstrated that a force and frequency-weighted filter network could be developed for processing continuous biomechanical measures of repetitive wrist motions and exertions. The current study achieves the objective by modelling subjective discomfort for repetitive wrist flexion using controlled posture, pace and force. A three-level fractional factorial experiment was conducted involving repetitive wrist flexion (2 s/motion, 6 s/motion, 10 s/motion) from a neutral posture to a given angle (10 degrees, 28 degrees, 45 degrees) against a controlled resistance (5 N, 25 N, 50 N) using a Box Behnken design. Ten subjects participated. Discomfort was reported on a 10 cm visual analogue scale. Results of response surface regression analysis revealed that main effects of force, wrist flexion angle, and repetition were all significant (p < 0.05) and that no second-order effects were observed. Linear regression analysis on these factors established a discomfort model on which the filter characteristics were based. The pure error test model revealed no significant lack of fit (p > 0.05). The continuous model was compared and agreed with discrete psychophysical data from other published studies. The model was used for generating parameters for a force and frequency-weighted digital filter that weighs continuous wrist postural signals with corresponding force in proportion to the equal discomfort function as a function of frequency of repetition. These filters will enable integration of large quantities of biomechanical data in field studies.