如何加强产品质量管理工作的探讨

从人员质量意识、产品设计质量、原材料/元器件的控制、人员操作质量、产品评审力度等方面,分析质量管理工作中存在的难点,并提出相应的解决措施.     

真空钙热还原炉渣的综合利用研究

研究了从真空钙热还原炉渣中回收稀土的工艺条件；采用本工艺得到的合格稀土溶液，其回收率达65．41％；副产品氟化钙用作炼硅铁合金的助熔剂，使钙热还原炉渣得到综合利用。     

An inverse solution methodology for estimating the diffusion coefficient of gases in Athabasca bitumen from pressure-decay data

An inverse solution methodology is developed for the estimation of diffusion coefficient of gases in highly viscous, oil-sands bitumens from isothermal, pressure-decay measurements. The approach involves modeling the rate of change in pressure using the diffusion equation for the liquid phase coupled with a mass balance equation for the gas phase. The inverse solution framework is utilized to arrive at two graphical techniques for estimating the diffusion coefficient. Both techniques involve the determination of the slope of a straight line resulting from plotting the experimental data in accordance with the developed model. An advantage of the proposed techniques is that the diffusion coefficient is estimated directly, i.e. without making it an adjustable parameter. The novelty of the proposed method is in its simplicity as well as its ability to isolate portions of the pressure-decay data affected by experimental fluctuations. The effect of the initial pressure on the predicted diffusion coefficient and pressure-decay profile was also investigated. The diffusion coefficients of CO₂, CH₄, C₂H₆ and N₂ in Athabasca bitumen at 50–90 °C and about 8 MPa were estimated and compared with literature values.     

开放的ladder型无反转激光系统的稳定性分析

利用开放的ladder型无反转激光系统的密度矩阵运动方程组的定态解和激光场运动方程分析了系统的稳定性。结果表明：如果增益大于激光腔损耗，则零解是不稳定的；如果增益小于激光腔损耗，则零解是稳定的；如果增益大于激光腔损耗，则非零解是稳定的。     

一种新的混合相位反褶积方法

在地震资料处理中,常用预测反褶积方法提高地震资料的分辨率,它具有两个基本的假设条件:①地震子波是最小相位;②反射系数序列是随机过程。上述假设条件与实际地震子波的混合相位存在较大差别。为此,笔者在借鉴前人研究的基础上,提出了一种新的混合相位反褶积方法。其实现过程为:①根据地震记录的自相关和地震子波自相关之间的关系,由最小二乘法拟合出地震子波的振幅谱,进而计算出地震子波的自相关;②利用计算出来的地震子波自相关设计一个最小相位滤波器,然后加一个延迟量于自相关函数的主对角线上,将最小相位反滤波器分解为一个长度很短的滤波器,再与一个长度较长的滤波器进行褶积,可得到一系列的混合相位子波和混合相位滤波器;③将得到的混合相位滤波器和原始地震道进行褶积,选取一定的判别准则,以选出最佳的混合相位滤波器以及相应的混合相位子波。通过模型试算和实际资料处理可知,分时窗反褶积的效果要好于单时窗反褶积,混合相位反褶积效果好于最小相位反褶积。在分时窗求取地震子波时,为了得到更好的反褶积效果,要注意时窗宽度与算子长度之间的关系。     

Boundary knot method for 2D and 3D Helmholtz and convection–diffusion problems under complicated geometry

The boundary knot method (BKM) of very recent origin is an inherently meshless, integration‐free, boundary‐type, radial basis function collocation technique for the numerical discretization of general partial differential equation systems. Unlike the method of fundamental solutions, the use of non‐singular general solution in the BKM avoids the unnecessary requirement of constructing a controversial artificial boundary outside the physical domain. The purpose of this paper is to extend the BKM to solve 2D Helmholtz and convection–diffusion problems under rather complicated irregular geometry. The method is also first applied to 3D problems. Numerical experiments validate that the BKM can produce highly accurate solutions using a relatively small number of knots. For inhomogeneous cases, some inner knots are found necessary to guarantee accuracy and stability. The stability and convergence of the BKM are numerically illustrated and the completeness issue is also discussed. Copyright © 2003 John Wiley & Sons, Ltd.     

一种抗干扰能力极强的计算机通信接口电路

设计了一种结构简单，抗干扰能力极强的计算机通信接口电路。该电路利用模拟开关实现了全数字二态电平（1，0）与三态电平(1，0，-1)之间的相互转换；利用模拟开关导通电阻的动态效应以及MOS晶体管开启电压Vτ的衬偏效应，提高了接收电路的抗干扰能力，提出了一种与共模干扰无关的模拟数字混合接收电路。     

A new bubble-point-pressure correlation for the binary LiBr/H2O solution

In accord with the increasing concern about the global environmental issues, the absorption refrigeration heat-pump systems are currently being considered very promising and attractive. For the purpose of supporting the advanced R&D technology in this area, we have developed a novel correlation to represent the bubble-point pressures of LiBr H₂O solutions. The developed correlation covers the most extensive range of validity ever proposed: 273–483 K for temperatures, 0.05 kPa to 1.0 MPa for pressures. and 29 76 wt% LiBr for concentrations.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994. Boulder, Colorado, U.S.A.     

Substituted uracils as corrosion inhibitors for copper in 3% NaCl solution

Substituted uracils were tested as corrosion inhibitors of copper in 3% NaCl medium using electrochemical polarisation, impedance measurements and non-electrochemical techniques (weight loss, IR and UV-visible). This study permitted to follow the evolution of the inhibitory effect of the uracil derivatives, according to their substituents, on copper in 3% NaCl medium. Comparison of results showed that dithiouracil (DTUr) was the best inhibitor. The maximum inhibition efficiency reached 98% at 10⁻³ M. DTUr adsorbs on the copper surface according to the Frumkin isotherm model.     

具有偏差变元的Volterra型系统的周期正解

利用Mawhin重合度理论研究了一类具有偏差变元的Volterra型系统周期正解的存在性问题，得到了一个新的存在性定理。