亲水性低黄变氨基改性硅微乳的合成

以D4和改性氨基硅烷偶联剂为原料，采用磺酸类催化剂和非离子型复合乳化剂，通过将预乳液滴入催化剂的水溶液的方法，制成了氨基改性硅微乳。预乳液的滴加速度对产品的透明度有很大影响；硅微乳具有良好的酸、碱、阴离子表面活性剂、离心、热稳定性，并可与荧光增白剂、还原性染料、活性染料同浴使用；用其整理的织物具有良好的亲水性和低黄变性。     

多波束修正母线新型偏轴旋转反射面天线

以抛物线为母线的偏轴旋转抛面天线可以在锥面上或平面上实现宽角域扫描，或形成多束波天线，但沿性面和垂直之间的中间平面，子波束孔径上光程差很大，导致天线性能降低，本文以新型母线取代抛物线，创立新型偏轴旋转反射面天线，使天线性能得到显著改善。     

M-Estimation for regressions with integrated regressors and arma errors

Abstract.  General M -estimation is developed for regression models with integrated regressors and autoregressive moving average (ARMA) errors, in which the ARMA parameters are jointly estimated with the regression parameters. The large sample distribution of the M -estimator is derived. Allowing the regressors to be dependent on the error terms, a parametric 'fully modified' (FM) M -estimator is proposed. In cases of ARMA errors, a Monte-Carlo experiment reveals superiority of the parametric estimators over the semiparametric FM M -estimator of Phillips Econometric Theory 11 (1995, p 912) in terms of empirical mean squared error.     

Detection of GMO in food products in Brazil: the INCQS experience

Regulations for the use and labeling of genetically modified organism products and derived ingredients are being implemented worldwide, what demands reliable and accurate methods to detect genetically modified organisms (GMO) in raw materials and food products. This study aimed at monitoring products derived from GMO in the Brazilian market using detection methods for the presence of Roundup Ready soybean, Bt176 and MON 810 maize. The results demonstrate for the first time the presence of GM-soy in Brazilian food products, reinforcing the need for the development of accurate quantitative methods in routine analyses.     

各向异性压电陶瓷材料

本工作制备了添有少量Pb(Zn_(1/3) Nb_(2/3))O_3,Bi(Zn_(1/2) Ti_(1/2))O_3和MnO_2的高电阻率,高密度的改性(PbCa)TiO_3压电陶瓷。这种陶瓷在150℃和施加40—50kV/cm电场条件下极化之后显示出大的各向异性压电特性。它具有高的厚度扩张模式机电藕合系数Kt,高的机械品质因素Qm低的介电常数,而平面耦合系数Kp值极小。于是,这种新的压电材料适于制作高频陶瓷滤波器超声换能器,金属探伤检测器,以及声表面波器件等。     

海洋大气近地层折射指数模式及其在蒸发波导分析上的应用

利用Ｍｏｎｉｎ－Ｏｂｕｋｈｏｖ相似理论给出了不同大气结条件下海洋大气近地层折射指数模式，并利用这些模式分析了蒸发波导内可能存在的波导模，给出了确定蒸发波导所能捕获最大电磁波波长及相应最低频率的计算式并对其在不同大气层结条件下的计算结果进行了比较，发现在不稳定、中性和近中性层结条件下，其计算结果比较接近，但在强稳定层结条件下，差异显著，最后给出了射线追踪方程，并通过用多层线性模式来近似蒸发波导内大气     

SBS改性沥青低温延度影响因素分析

阐述了SBS改性沥青低温延度的主要影响因素。通过对基质沥青针入度、反应温度、循环剪切时间及储存条件等进行优化和控制，可提高产品低温延度质量，延缓产品的老化，储存周期明显改善。     

Remeshing for metal forming simulations—Part I: Two‐dimensional quadrilateral remeshing

In this paper, a general framework of practical two‐dimensional quadrilateral remeshing, which includes the determination of remeshing time, automatic quadrilateral mesh generation, and data transfer process, will be formulated. In particular, the current work contains new algorithms of mesh density specification according to the distribution of effective strain‐rate gradients, mesh density smoothing by fast Fourier transform (FFT) and low‐pass filtering techniques, coarsening it by node placement scheme, and a modified Laplacian mesh smoothing technique. The efficiency of the developed remeshing scheme was tested through three practical two‐dimensional metal forming simulations. The results clearly indicate that the algorithms proposed in this study make it possible to simulate two‐dimensional metal forming problems efficiently and automatically. Copyright © 2002 John Wiley & Sons, Ltd.     

一点法产能评价的改进方法

一点法试井操作简单方便,但其测试时间短,计算结果误差较大。针对上述问题,从气井渗流理论出发,利用单井储层特征参数,推导计算气井达到拟稳态的时间,再利用该时间计算气井的产能及无阻流量。应用此方法对西部某气田的一点法测试进行了校正,结果准确可靠,为以后的开采配产作业提供依据。     

Application of high-order quadrature rules to time-domain boundary element analysis of viscoelasticity

This paper presents an accurate and efficient method for the treatment of time integrals in time-domain boundary integral equations for viscoelastic problems. First, the integral equations in space and time are derived for linear viscoelastic and thermo-viscoelastic problems. Then various quadrature rules are discussed for the computation of time integrals. A modified Simpson's rule is proposed as an effective integration scheme. The proposed procedure requires a small computational effort and it is applicable even in time-domain boundary element analysis of many different problems. Numerical results of example problems show the accuracy and effectiveness of the proposed method.