Delayed delivery of surviving triplet after fetal reduction and spontaneous abortion

In multiple pregnancies, survival of remaining fetuses after premature death and delivery of one fetus is uncommon. We report a case of a triplet pregnancy that was reduced to twins at the 14th gestational week and then had preterm premature rupture of membranes and intrauterine fetal death of one twin at the 17th gestational week. To save the surviving fetus, delivery of the dead fetus and ligation of the umbilical cord at the cervical level were performed. We also performed McDonald cervical cerclage to keep the placenta of the dead fetus as well as that of the surviving one in the uterine cavity. After a series of aggressive procedures, including immediate administration of tocolytic agents, and antibiotic prophylaxis to prevent infection and preterm labor, the surviving fetus was delivered vaginally 73 days later due to intractable uterine contractions. After a 10-week hospital stay, the infant boy, weighing 2,500 g, was discharged without any sequelae. To our knowledge, this was the longest interval between deliveries in a triplet pregnancy reported in Taiwan. With adequate intensive management, a satisfactory outcome of the fetus and mother in such cases is possible.     

Failure probability evaluation for normally distributed load-strength model with unknown parameters

The failure probability evaluation methods for load-strength interference model are established when both load, L, and strength, S, follow normal distributions, assuming none of the normal distribution parameters are known. Based on Fisher's fiducial analysis, a failure probability evaluation method is obtained for single load application. A numerical integration method is developed to evaluate the failure probability for multiple load applications.     

生物降解型聚碳酸顺丁烯二酸亚乙酯 1、合成和表征

用CO_2、环氧乙烷、顺丁烯二酸酐进行三元共聚首次得到聚碳酸顺丁烯二酸亚乙酯(PECM),并用IR、~1H NMR、DSC等进行了表征,共聚物链中CO_2和MA单元随机分布,不饱和单元可在0～0.5mol分数之间调节。共聚过程不发生双键交联和构型转化。环氧乙烷的转化率可高达到93％。控制PECM链上的双键含量并使之发生自由基加成反应,得到对热较稳定的可溶性产物。     

高频脉冲微束等离子电弧温度场的测试及分析

本文首次采用单波长激光干涉技术，对恒定直流和高频脉冲电流微束等离子电弧温度场进行了测试，并做了分析比较。以电弧温度分布为基础分析了高频脉冲电流微束等离子电弧收缩、稳定的原因。     

内燃机节油率计算的探讨

讨论比较了现有内燃机节油率计算方法的优缺点、产生误差的原因，提出了采用曲线拟合的方法求取率的新方法。文中给出了计算公式和计算步骤，通过编制计算机程序，计算了几种典型发动机的节油率指标，并传统的按度试验数据逐点计算方法进行了对比，证明此方法是一种比较客观、科学的节油率指标计算方法。     

Synthesis of ultrafine LiCoO2 powders by the sol-gel method

Ultrafine high-temperature (HT) LiCoO₂ powders were synthesized by the sol-gel method using polyacrylic acid (PAA) as a chelating agent. The decomposition process of the gel precursor was examined to determine the crystallization temperature and the dependence of the physicochemical properties of HT-LiCoO₂ powders on the PAA quantity was extensively investigated. Polycrystalline HT-LiCoO₂ powders, composed of very uniformly sized ultrafine particulates with an average particle size of 30–50 nm and a specific surface area of 2.3–17 m²g^–1, could be obtained at the lower calcination temperature of 550 °C and the shorter calcination time of 1 h compared to the solid-state reaction.     

DF_4内燃机车柴油机润滑油的热重分析

通过对DF_4内燃机车柴油机润滑油的热重曲线TG和微商热重曲线DTG的分析,探讨了这种润滑油的衰变规律。     

油溶性减阻功能聚合物的研制

介绍了以混合α-烯烃为原料,制备了具有减阻功能的共聚物。讨论了催化剂浓度、聚合温度、预聚合时间、原料单体中杂质含量对共聚物特性粘度和转化率的影响。试验表明,在较低的催化剂浓度和预聚合温度下,能得到较高分子量的聚合物。气相色谱法和DSC法测定其组成和单体混合物的组成基本一致,表明共聚物是一种无规的梳状结构聚合物。该聚合物达到较高特性粘度时,能获得较好的减阻率。