Flow stress of high density polyethylene and nylon 66 at high rates of strain

Measurement of the flow stress of high density polyethylene (HDPE) and nylon 66 at strain rates of 10³ s^?1 using a split Hopkinson pressure bar technique is discussed. The flow stress at a strain of 10% has been determined for both polymers at 20°C. The intrinsic errors involved in this technique are briefly reviewed. The results indicate that the flow stress of HDPE and nylon 66 were 50MPa and 150MPa, respectively, at strain rates of about 10³s^?1.     

Consideration of the BDNF gene in relation to two phenotypes: Hoarding and obesity.

The gene coding for the brain derived neurotrophic factor (BDNF) has emerged as an interesting candidate for multiple brain and brain disorder-related phenomena. The primary aim of the present investigation was to consider the relationship between the BDNF Val66Met variant and two phenotypes: compulsive hoarding as a symptom dimension of obsessive–compulsive disorder (OCD), and body mass index (BMI). We examined the BDNF gene in a large (N = 301) clinical sample of probands with OCD. Participants were classified as hoarding or nonhoarding using a strict, multimeasure grouping approach. Results revealed that the Val/Val genotype was linked with hoarding classification and more severe hoarding behaviors, as well as greater BMI levels. Hoarding status was also associated with greater BMI scores, with individuals in the hoarding group being far more likely to be classified as obese compared with the nonhoarding group. Our findings may provide a distinct avenue through which hoarding and BMI could be linked. These findings are suggestive of a complex gene, body weight, and psychopathology relationship wherein a primitive, survival “thrifty gene” strategy may be conserved and represented in a subgroup of humans manifesting severe hoarding symptoms. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

国外锦纶66帘子线纺丝油剂应用初探

探讨了德国ＰＡＰ－２６０油剂与日本三洋公司ＡＺ－６０油剂在我公司锦纶的帘子线纺丝试产中的应用情况，指出它们各自优劣和改进之处．     

超细特锦纶66及其仿羊绒纱线的性能研究

基于对超细特PA66短纤维与山羊绒在强伸性能、吸湿与电学、热力学等物理性能的研究,分析了超细特PA66短纤维与山羊绒在性能上的相似之处;设计了4种超细特PA66仿羊绒纱线的工艺方案,研究了超细特PA66短纤仿山羊绒纱线的服用性能,为化纤仿真产品开发提供了借鉴。     

静电纺PA6/66纤维膜的稳定性研究

针对染料废水高酸碱度特性及采用化学试剂清洗膜时,对材料的化学稳定性和湿热稳定性的要求,研究了常温下静电纺PA 6/66纤维膜在不同p H值的盐酸和氢氧化钠溶液、去离子水、常用杀菌剂质量分数为1%双氧水和0.5%次氯酸钠溶液中的稳定性,及其在去离子水中的湿热稳定性。结果表明,经90℃湿热处理15 min后的静电纺PA 6/66纤维膜,再在质量分数为1%双氧水和0.5%次氯酸钠溶液中处理4 d后,其形态结构和力学性能遭到严重破坏,而在其他试剂中浸泡处理8 d后仍能保持较好的力学性能。在40℃热水中处理6 d后,纤维表面形态和力学性能保持性较好,而在60℃热水中,随着处理时间增加,纤维表面形态和力学性能遭到严重破坏。     

尼龙66装置工艺气往复压缩机简述

本文对尼龙66盐工程中所用工艺气往复压缩机简况作综合介绍,可以给今后工程中所选用工艺气压缩机借鉴和参考。     

金属基复合材料的摩擦学性能及结合强度试验研究

以聚酰胺66（PA66）、聚苯硫醚(PPS) 及65Mn钢板为主要原料,制备了一系列不同配比的金属基复合材料,并对这些材料进行不同条件下的摩擦学性能试验,最后通过结合强度试验来分析材料间的结合强度。结果表明,复合材料的摩擦因数及磨损速率随着聚酰胺66的增加而降低;同种材料的摩擦系数及磨损速率随着载荷和对摩速度的增加而先增大后减小;结合强度试验表明金属基复合材料的结合强度随着聚苯硫醚的增加而逐渐增大。     

UiO-66膜的制备及对正异丁烷的分离

采用擦涂法在Al2O3支撑体上引入ZrO2层,利用晶种二次生长法在ZrO2层上成功制备了UiO-66膜。通过XRD和SEM测试手段对晶种和膜的结构和形貌进行了表征。在温度为298 K,压力为0.08 MPa下,测试气体分子的渗透性能检测了UiO-66膜的完整性。考察压力和温度对i-C4H10和n-C4H10两种气体在UiO-66膜上的渗透速率的影响,研究了UiO-66膜对i-C4H10和n-C4H10两种气体的渗透选择性能。结果表明,采用多次擦涂法引入ZrO2层后,获得了覆盖度高且膜层厚度均匀的UiO-66膜,膜厚度为5 μm。UiO-66膜对i-C4H10和n-C4H10两种气体具有反向渗透性能,在操作压力为0.08 MPa,温度为298 K时,UiO-66膜对i-C4H10/n-C4H10两种气体的理想渗透选择性达3.60。渗透速率分别为4.39?10-7 mol/(m2?s?Pa)和1.22?10-7 mol/(m2?s?Pa)。     

比色-表面增强拉曼散射双信号输出指示标签对凡纳滨对虾新鲜度的实时监测

目的 开发一种灵敏且稳定的双信号输出指示标签,并实现对凡纳滨对虾（Litopenaeus vannamei）新鲜度的实时监测。方法 基于聚乙烯醇（polyvinyl alcohol, PVA）/琼脂复合基质,结合花青素（anthocyanins, ACNs）、银包金纳米颗粒（Au@AgNPs）与金属有机框架材料UiO-66,通过浇铸法制备双信号输出指示标签。其次,通过储藏稳定性、紫外稳定性以及防迁移性实验考察UiO-66对标签的增稳作用。以氨气、二甲胺和三甲胺为特征挥发性标志物,评估标签的气敏响应性能。最终将其应用于凡纳滨对虾的新鲜度实时监测。结果 相对于未添加UiO-66的标签,UiO-66的加入有效固定了ACNs,提升了标签的紫外稳定性和储藏稳定性。此外,该标签对氨及胺类气体表现出优异的响应能力。在凡纳滨对虾新鲜度监测应用中,指示标签的颜色随凡纳滨对虾新鲜度变化从紫红色逐渐变为浅蓝色。基于表面增强拉曼散射（surface-enhanced Raman scatting, SERS）信号建立的偏最小二乘回归（partial least square regression, PLSR）模型对挥发性盐基氮（total volatile base nitrogen, TVB-N）值的预测性能优异,其中校正集决定系数（calibrated coefficient of determination, R2C）为0.951,交叉验证集决定系数（cross-validated coefficient of determination, R2CV）为0.899,预测集决定系数（predicted coefficient of determination, R2P）为0.966,剩余预测偏差（residual prediction deviation, RPD）为4.765。结论 本研究构建了一种比色-SERS双信号输出指示标签,可同步实现凡纳滨对虾新鲜度可视化鉴别与TVB-N值的高灵敏度预测,为新型的食品智能包装的设计提供了参考。