结构振动控制中压电阻尼技术研究—压电被动阻尼技术（一）

压电阻尼技术有两种类型：压电被动阻尼技术和压电主动阻尼技术。本文对其中的压电被动阻尼技术进行了研究，结果表明：通过给压电元件并联适当的外部电路，可使压电系统具有与粘弹阻尼材料及动力吸振器相似的物理特性。合理配置电路参数，可以实现最优阻尼比。     

计算机在高炉鼓风机上的应用

本文介绍了捷克和斯洛伐克ＣＫＤ公司的ＭＡＲＫ工业控制计算机构成及其在高炉鼓风机控制系统中的应用，较详细地说明了高炉鼓风机的工艺控制思想。     

A spectrally efficient constant envelope modulation technique forPCS and mobile communications

A newly developed constant envelope FQPSK modem/radio architecture, which employs a modified double-jump (DJ) filter in the cross-correlated FQPSK system, is proposed for personal communications systems (PCS) and mobile radio applications. Power efficiency, spectrum efficiency, BER, and system capacity of this system are investigated in a non-linear amplified (NLA) Rayleigh fading environment. We demonstrate that with the simplest threshold detectors (binary robust eye diagrams in I and Q channels), this system is 4-7 dB more power efficient than the US digital cellular and Japanese Handyphone standard π/4-QPSK, 50%-100% more spectrally efficient than the European standard GMSK, and it almost double the capacity of GMSK     

On contact resistance measurement using four-terminal Kelvinstructures in advanced double-polysilicon bipolar transistor processes

The contact between a polycrystalline silicon (polysilicon) layer and a silicon substrate is investigated for an advanced double-polysilicon bipolar transistor process. Contact resistances are measured using four-terminal cross bridge Kelvin structures. The specific contact resistivity of the interface and the sheet resistance of the doped substrate region directly underneath the contact are extracted using a two-dimensional simulation model originally developed for metal-semiconductor contacts. The extracted sheet resistance values are found to be larger than those measured using van der Pauw structures combined with anodic oxidation and oxide removal. During the fabrication of the contacts, epitaxial realignment of the polysilicon in accordance to the substrate orientation and severe interdiffusion of dopants across the interface take place, which complicate the characterization. The validity of the two-dimensional simulation model applied to the poly-mono silicon contact is discussed     

Calculation of the partial capacitance in a system of conductorswithin the calculable resistor

A method for calculating the partial capacitance (PC) in a multiconductor system (a system of conductors) consisting of n conductors parallel to the shield axis inside earthed cylindrical shields is discussed. Formulas for the PC in SI units are given. The PC is defined as the conductor-to-conductor capacitance and conductor-to-shield capacitance. These methods and formulas are suitable for calculating the PC of Gibbings' resistors with a calculable ac/dc resistance ratio     

电磁测量中误差产生的原因及消除方法

对电磁测量中所产生误差的原因进行分析,提出了消除不同误差所应采取的方法。     

激光远距作用的机制与效应

本文定量分析激光远距作用的机理并对它们在治癌中的作用作简要的论述。     

树脂热解炭制备碳化硅晶须

用自制的配合醛树脂热解和炭源，用ＳＩＯ２超细汾作原，根据碳热还原原理，利用常规加热和微波加热两种方式，分别制备了直径在纳米级的ＳｉＣ晶须，Ｘ射线衍射、透射电检测结果表明：制备工艺和条件对ＳｉＣ晶须的性质有较大的影响。     

Preparation and optical properties of CdxHg1-xTe doped silica glass

In this paper, the Cd_xHg_1-xTe (x=1-0.7) doped silica glass was prepared through two step sol-gel process and in-situ growth technique from tetraethoxysilane (TEOS), cadmium acetate, mercury acetate and telluric acid. The influence of various factors on the glass was studied. The structure of the microcrystals was investigated by XRD. The absorption and transmittance spectrum of the composite showed that the shift of absorption edge was in conformity with the quantum size effect. The third-order nonlinear optical susceptibility χ⁽³⁾ was measured by the degenerate four wave mixing (DFWM). The values of χ⁽³⁾ was in the range of 10^-11-10^-12 MO esu at wavelength of 1.06 μm.     

超高增压柴油机与斯特林发动机复合运行的分析

本文对超高增压柴油机与斯特林发动机的复合运行进行了初步的探讨,陈述了这种复合运行作为未来发动机技术发展方向之一的可能性。