Nd：YAG激光器中的自锁模

本文报道在Nd:YAG激光器中首次获得的自锁模脉冲序列.自锁模是由于Nd:YAG棒中的自相位调制引起的.在主被动对撞锁模运转情况下,自锁模对脉冲波形有较大的影响.     

Asymptotic speeds of spread and traveling waves for monotone semiflows with applications

The theory of asymptotic speeds of spread and monotone traveling waves is established for a class of monotone discrete and continuous‐time semiflows and is applied to a functional differential equation with diffusion, a time‐delayed lattice population model and a reaction‐diffusion equation in an infinite cylinder. © 2005 Wiley Periodicals, Inc.     

三维内肋管内插入螺旋扭带的强化传热实验

本文分别以水和乙二醇为工质，在Ｒｅ数范围为：６００～４００００，Ｐｒ数范围为：５．５～１１０之间，对四根分别插入三种不同扭率螺旋扭带的三维内助管内的换热和流阻特性进行了实验研究。结果表明：三维内肋管内加装扭带的强化传热技术适用于低Ｒｅ数下高Ｐｒ数工质的管内对流换热强化。根据实验值得到了流阻和换热关联式。     

灰色Verhulst模型的样条插值函数的残差修正

本用样条函数对灰色Verhulst模型的残差序列进行插值拟合，然后作用于二阶线性微分方程，并以此修正原模型，得到一种新的预测模型的数值解，提高了拟合的精确度。     

铜、锌在5-Br-PADAP和表面活性剂体系中的分光光度法同时测定

5一Br—PADAP在阳离子表面活性剂溴代十六烷基三甲胺存在下同时测定Cu^2 和Zn^2 ，找出最佳实验条件，对水和血清测定结果令人满意．     

催化动力学测定痕量砷(Ⅲ)

在醋酸介质中,发现痕量砷(Ⅲ)能灵敏地催化高碘酸钾氧化靛红la褪色的指示反应,研究了该催化反应的最佳条件与动力学参数,建立了一种新的测定痕量砷(Ⅲ)的方法。该法的线性范围0.0-40μg/LAs(Ⅲ),检测限为1.92×10-6g/L,用于环境水样中砷(Ⅲ)的测定,获得了满意的结果。     

聚丙烯酸长链酯的Huggins常数与其分子量的依赖性关系

聚丙烯酸高碳醇酯(PBA)及聚丙烯酸十八醇酯(POA)是具有长烷基侧链的梳状聚合物,在溶剂苯中的Huggins常数(k′)随其分子量(M)的变化而变化.在PBA-苯体系中发现,当M低于某一临界分子量(MLC)时,k′随分子量的降低显著增大;当M大于某临界分子量(MHC)时,k′随分子量的升高而增大;当M在MLC～MHC时,k′基本上保持不变.而在POA-苯体系中发现,当M低于某一临界分子量(MC)时,k′随分子量的降低显著增大;当M大于该临界分子量(MC)时,k′在0.33～0.43变化.文中同时给出了精确算法用来计算PBA-苯体系及POA-苯体系中PBA及POA的特性粘度.当k′＞0.758时,用稀释外推法计算;当0.758＞k′＞0.426时,用一点法公式[η]=ηsp/C(√)ηr计算;当0.426＞k′＞0.334时,用另一一点法公式[η]=(√)2(ηsp-lnηr)/C计算.     

饮食中微量元素砷的分布规律与人体健康关系

采用催化动力学光度法测定了六大类(共三十种)样品中的总砷含量，探讨了砷在食品中的分布规律，建立了砷在人体中的安全系效和积累系效的效学评价公式，用于评价砷与人体健康的关系，这对人们选择食物有一定的指导意义。     

Formation of β‐iPP in isotactic polypropylene/ethylene–propylene rubber blends: Effects of preparation method,composition, and thermal condition

The effects of preparation method, composition, and thermal condition on formation of β‐iPP in isotactic polypropylene/ethylene–propylene rubber (iPP/EPR) blends were studied using modulated differential scanning calorimeter (MDSC), wide angle X‐ray diffraction (WAXD), and phase contrast microscopy (PCM). It was found that the α‐iPP and β‐iPP can simultaneity form in the melt‐blended samples, whereas only α‐iPP exists in the solution‐blended samples. The results show that the formation of β‐iPP in the melt‐blended samples is related to the crystallization temperature and the β‐iPP generally diminishes and finally vanishes when the crystallization temperature moves far from 125 °C. The phenomena that the lower critical temperature of β‐iPP in iPP/EPR obviously increases to 114 °C and the upper critical temperature decreases to 134 °C indicate the narrowing of temperature interval, facilitating the formation of β‐iPP in iPP/EPR. Furthermore, it was found that the amount of β‐iPP in melt‐blended iPP/EPR samples is dependent on the composition and the maximum amount of β‐iPP formed when the composition of iPP/EPR blends is 85:15 in weight. The results through examining the effect of annealing for iPP/EPR samples at melt state indicate that this annealing may eliminate the susceptibility to β‐crystallization of iPP. However, only α‐iPP can be observed in solution‐blended samples subjected to annealing for different time. The PCM images demonstrate that an obvious phase‐separation happens in both melt‐blended and solution‐blended iPP/EPR samples, implying that compared with the disperse degree of EPR in iPP, the preparation method plays a dominant role in formation of β‐iPP. It is suggested that the origin of formation of β‐iPP results from the thermomechanical history of the EPR component in iPP/EPR. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1704–1712, 2007     

白光干涉条纹变密的原因探讨

讨论了在测定透明介质折射率的过程中彩色条纹变密的现象，并在其基础上分析其成因：一是由于媒质折射率加大；二是由于平形板介质平行度不好造成楔形的倾角变大，最后在实验中验证了理论结果。