MOSFET亚阈特性分析与低温按比例缩小理论的研究

器件尺寸按比例缩小是实现超大规模集成电路的有效途径，但寄生和二级效应却将器件限在一定的水平，本文在对比分析常温与低温下小尺寸器件效应的基础上，重点研究了ＭＯＳ器件亚阈特性对器件性能及按比例缩小的影响，并根据低温工作的特点，提出了ＭＯＳ器件一种低温按比例缩小规则，该原则对低温器的优化设计，从而更大程度在提高电路与系统性能具有重要的指导意义。     

HT－7托卡马克的八管弹丸注入器

介绍了用于ＨＴ－７托卡马克的的八管弹丸注入器的物理、工程设计原理和结构特点及配置的各种诊断手段。注入器采用气动发射技术，弹丸为１ｍｍ×１ｍｍ，１．２ｍｍ×１．２ｍｍ，１．５ｍｍ×ｌ．５ｍｍ圆柱体氢丸，丸速０．８～１．５ｋｍ／ｓ工作频率１～８Ｈｚ。     

A method to estimate entropies and heat capacities applied to alkali oxides

We present a method that is useful in the estimate and assessment of heat capacity data. The approach is based on an analysis of the logarithmic average of the phonon frequencies. In this quantity, that may be easily derived from experimental data on the vibrational entropy, the influence of atomic masses can be exactly accounted for even in polyatomic solids. Our method is applied to Li₂O, Na₂O, K₂O, Rb₂O, and Cs₂O. In particular, literature data for K₂O are critically examined.     

Evolution of BET internal surface area in glassy carbon powder during thermal oxidation

It is demonstrated that glassy carbon powder can be thermochemically activated. During activation, a film with open pores is created on the glassy carbon particles. This film has a large internal surface area, which is accessible to liquids and gases. A simple model for the evolution of the internal surface area in glassy carbon powder during thermochemical gas-phase oxidation is also presented and compared with experimental data. Experimental results are in qualitative agreement with the model. We found that a sharp particle size distribution is desirable with regard to potential technical applications.     

砷化镓声电荷转移延迟线的设计与工艺研究

由于声电荷转移(ACT)这一新颖的高速缓冲抽样技术的发明,使得新一代高速高频信号处理器件的实现成为可能。本文研究了第二代平面结构的ACT器件转移沟道的电位分布特性,给出了平面结构ACT延迟线的设计,并研究了ACT器件的工艺实现。     

NUMERICAL SIMULATION OF STREAMBED HEAT TRANSFER

１．　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｓｉｍｕｌａｔｉｏｎｏｆｓｔｒｅａｍｗａｔｅｒｔｅｍｐｅｒａｔｕｒｅｉｓｓｉｇｎｉｆｉｃａｎｔｌｙｉｍｐｏｒｔａｎｔｆｏｒｔｈｅｓｔｕｄｙｏｆｎｕｍｅｒｉｃａｌｍｏｄｅｌｉｎｇｏｆｒｉｖｅｒｉｃｅｐｒｏｃｅｓｓｅｓ［１］　．Ｈｉｓｔｏｒｉｃａｌｌｙ，ｔｈｅｍａｔｈｅｍａｔｉｃａｌｍｏｄｅｌｉｎｇｏｆｔｈｅｔｒａｎｓｐｏｒｔａｎｄｆａｔｅｏｆｈｅａｔｉｎａｗａｔｅｒｂｏｄｙｈａｓｂｅｅｎｔｈｅｓｕｂｊｅｃｔｏｆｅｘｔｅｎｓｉｖｅｓｔｕｄｙｆｏｒｖａｒｉｏｕｓｒｅ…     

Fatigue behaviour of a phenolic matrix composite

This paper presents results of a fatigue life investigations carried out in plate specimens of a fibre-glass-reinforced phenolic matrix composite. Tensile and Young's modulus data were obtained at four different testing temperatures (room temperature, 100, 150 and 200 °C). The fatigue S−N data were obtained at room temperature only and for two stress ratio values (R=0 and 0.4). Fatigue and tensile behaviour was assesesed in the composite with the fibres aligned in the longitudinal loading direction. The results were obtained for two values of volume fraction (0.28 and 0.42) and three different glass surface treatments. A detailed comparison of fatigue results is given taking into account several fatigue parameters and also the testing variables. Results of observations of SEM fracture surfaces are also presented.     

Cure reaction for modified diallylbisphenol A/diaminodiphenylsulfone/bismaleimide

The glass‐transition temperature as a function of curing conversion for a modified diallylbisphenol A/diaminodiphenylsulfone/bismaleimide (BMI) resin was investigated at different temperature regimes and modeled using a modified Di Benedetto equation. Although the relationship between the glass‐transition temperature and conversion of the BMI system conforms to the Di Benedetto equation for α < 0.6 and at lower cure temperatures, at higher cure temperatures the results deviated significantly from the equation; thus, it was an inadequate model for the system. Fourier transform IR analysis showed that the major crosslinking reactions did not occur during cure for the modified BMI at and below 150°C. However, as the cure temperature was increased, the crosslinking reactions responsible for 3‐dimensional network structures became more dominant. At 190°C the C? N? C_stretch vibration of the uncured maleimide ring converted into succinimide rings in the curing process. Simultaneously, a decrease was observed for the absorbance bands of ? C? H_bending (maleimide). The higher cure temperatures induced a significantly faster initial crosslinking rate and also resulted in a shorter period of time after which further crosslinking was retarded, because the increase in the crosslinks also physically slowed further crosslinking activity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 227–235, 2002     

片式多层电容电阻复合元件的研制

采用低温共烧陶瓷(LTCC)技术将电容、电阻元件集成在多层陶瓷基板里,构成了一种新型的片式多层复合元件,并研究了其制造工艺性能和频率特性。结果表明,片式多层电容电阻复合元件制造工艺适合批量化生产,并为片式多层LC滤波器、LTCC基板及器件的研发提供了极好的参考价值。     

A new approach to the mechanism of chlorine evolution: Separate examination of the kinetic steps using ac impedance on a rotating thin ring electrode

In the absence of a bulk diffusion effect, it is shown for the first time that the impedance spectra for the chlorine evolution reaction on a rotating thin ring electrode comprise three consecutive semicircles in the capacitive half of the complex plane. The first (highest frequency) semicircle is due to the charge-transfer resistance for chloride discharge and the simultaneous chlorine adsorption coupled to the double-layer capacitance. The second semicircle (around 5 Hz) is due to the adsorption and desorption of a chlorine intermediate. The third (lowest frequency, around 0.5 Hz) semicircle is due to the relaxation of surface oxygen species. The impedance data allow the steps of the overall reaction to be examined individually. On a Pt surface the rate of chloride discharge and simultaneous chlorine adsorption (the admittance of the first semicircle) is first order with respect to chloride concentration and has a potential-dependence close to 58 mV/decade. The rate of the adsorption and desorption process (the admittance of the second semicircle) is second order with respect to chloride concentration, and has a potential dependence close to 30 mV/decade. The time constant for the adsorption/desorption processes is ca 20 ms, independent of electrode potential in the range studied. These features are consistent with a mechanism in which a faster discharge reaction (Cl⁻ Cl_ad + e) is followed by a slower surface combination reaction (2Cl_ad → Cl₂), but inconsistent with mechanisms in which ion + atom desorption is predominant, the initial chloride discharge is slow, or a unipositively charged chlorine species is involved.