PVP改性水性聚氨酯的合成及应用

为改善涂层织物的防水透湿性,采用乳液聚合法制备聚乙烯吡咯烷酮(PVP)/水性聚氨酯(WPU)乳液。利用红外光谱对PVP/WPU膜进行结构表征,考察PVP质量分数和相对分子质量对PVP/WPU乳液性能及胶膜性能的影响,并与未改性水性聚氨酯涂层性能进行对比。结果表明:PVP和水性聚氨酯之间存在氢键作用。当PVP相对分子质量为8 000,质量分数为10%时,制备的改性乳液粒径小、存储稳定性好,成膜后仍较好地保留聚氨酯原有的弹性和力学性能;使用该改性乳液作为织物涂层剂,涂层织物静水压为393 mm H2O,透湿量为2 237 g/m2·24 h,与未改性水性聚氨酯涂层织物相比,静水压值和透湿量分别提高了17%和8%,显著改善了涂层织物的防水透湿性。     

纳米二氧化硅改性水性聚氨酯防水透湿涂层织物的制备及其性能

为提升水性聚氨酯涂层织物的防水透湿功能,采用R972疏水型气相纳米二氧化硅对水性聚氨酯进行共混改性,以涂层的方式对纯棉针织物进行整理。利用红外光谱仪、扫描电子显微镜和超景深显微镜对纳米二氧化硅水性聚氨酯复合涂层的结构和形貌进行表征。研究了纳米二氧化硅质量分数对织物防水透湿性能的影响。结果表明:疏水型气相纳米二氧化硅可以在水性聚氨酯体系中发挥良好的纳米效应,并且对水性聚氨酯涂层膜的结构并无较大影响;当纳米二氧化硅质量分数为1.5%时,涂层膜的吸水率降低55.4%,涂层织物的透湿量增加54.7%,耐静水压和接触角分别增大86%和131.4%,同时复合涂层的力学性能也得到了显著改善。     

热敏变色储能涂层织物的性能

采用传统的涂层工艺,选取水性聚氨酯涂层剂与溶剂型聚氨酯涂层剂将自制的热敏变色储能材料整理到织物上,并对涂层整理后织物进行变色效果、储能效果、拉伸断裂性能以及防水透湿性能等测试。结果表明,涂层整理后织物变色效果显著;水性涂层织物的储能性能比溶剂型聚氨酯涂层织物的储能性能好;涂层整理可以增加织物的强力,从而增加了织物的耐久性;溶剂型聚氨酯涂层织物和水性聚氨酯涂层织物的透湿性不是很好;涂层织物具有较好的防水性能。     

结晶性织物防水透湿整理剂的制备及应用

采用亲水性聚醚型形状记忆聚氨酯整理剂对织物进行防水透湿整理 ,试验结果表明 ,采用这种聚氨酯涂层的织物透湿量达到 3 5 0 0 g/m2 ·2 4h以上 ,防水性接近耐 4～ 5kPa水压 ,被水润湿的速度约为 15°/min ,对环境温度的响应范围是 11～ 2 1℃。对使用该涂层剂研制“智能型”防水透湿织物的可能性进行了分析     

改性羧甲基纤维素(MCMC)对聚氨酯PU防水透湿织物性能的影响研究

在用湿法生产高档防水透湿织物时,为改善成品性能,降低成本,经常要在涂覆液中添加一定量的填料如木粉、纸浆、纤维等产品.为了提高该产品透湿防水性.本实验采用改性羧甲基纤维素(MCMC)作为填充剂,制成聚氨酯PU微孔膜织物,并利用透湿杯、FX3000、TEXTESTAG测试透湿量、耐静水压等,探讨了改性羧甲基纤维素对聚氨酯PU微孔膜织物性能的影响.结果表明:以改性羧甲基纤维素为填充剂可改善织物的防水透湿性能.     

功能性防水透湿涂层织物性能及其影响因素

制造防水透湿织物的方法一般有高密织物生产路线和涂层整理生产路线。介绍了国内外防水透湿织物的开发过程、性能要求、防水透湿整理原理、透湿性的测试及计算方法,并对这两种路线生产的织物的透湿性进行比较;重点分析了亲水型防水透湿涂层织物性能的优越性及影响因素。     

聚氨酯涂层类防水透湿织物研究进展

文章介绍了防水透湿织物的性能特征和基本分类,以及聚氨酯涂层类防水透湿织物的研究现状;综述了聚氨酯织物涂层的最新改性方法。     

织物防水透湿整理技术近况(一)

防水透湿织物是近20—30年来陆续开发的高附加值产品之一。制造防水透湿织物的方法一般有高密织物路线和涂层整理路线。文章介绍防水透湿织物的开发过程、性能要求、防水透湿整理原理、透湿性的简易测试方法、防水透湿整理工艺(即层压法、湿法涂层、干法微孔涂层、干法元孔涂层)以及五种防水透湿织物适用性比较。     

织物防水透湿整理技术近况(二)

防水透湿织物是近20～30年来陆续开发的高附加值产品之一。制造防水透湿织物的方法一般有高密织物路线和涂层整理路线。文章介绍防水透湿织物的开发过程、性能要求、防水透湿整理原理、透湿性的简易测试方法、防水透湿整理工艺(即层压法、湿法涂层、干法微孔涂层、干法无孔涂层)以及五种防水透湿织物适用性比较。     

聚氨酯转移涂层织物的透湿防水性能

 利用亲水和非亲水性聚氨酯(PU)树脂,经一定的工艺加工成聚氨酯转移涂层织物。测量与分析了织物孔径结构、接触角、透湿量以及耐静水压等参数。结果表明,采用非亲水性PU树脂的涂层织物,仅有微孔透湿,透湿率低,但防水性好;而亲水性PU涂层织物,既有以水蒸气和液态水形式通过“溶解—扩散—吸附”传递;又有通过微孔质扩散,故该类亲水性PU涂层织物具有很好的透湿性能,但防水性不足,达不到PU涂层织物透湿性与防水性和谐统一的要求。     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

常用消毒灭菌法及其机理与应用

介绍了采用消毒灭菌方法,有加热消毒法,紫外线辐射法和化学药剂消毒法。常用化学药剂有醛类、含氯消毒剂、醇类消毒剂以及高锰酸钾、生石灰等,阐释了消毒与灭菌两个概念的区别。     

益生素、益生菌与结肠癌

介绍了益生素和益生菌及其作用机理。在动物模型中，有大量的数据证实益生素和益生菌能够预防癌症．而在人体内还没有直接实验证据。它们抑制癌症的确切机理目前尚不清楚，其抑制机理可能是：肠道菌群代谢活动的改变，肠道理化环境的改变，潜在的致癌物质的黏附和降解，肠道菌群的改变、抗癌或抗诱变物质的形成、提高宿主的免疫应答、影响宿主的生理活动以及发酵不能被消化的食物并形成有益代谢产物。     

European citizen and consumer attitudes and preferences regarding beef and pork

This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries.     

节能节水型印染助剂和设备的现状

从节能、节水、缩短工艺流程和环保的角度出发，介绍了国内外研制开发的一系列新型节能、节水型印染助剂和染整设备。     

原花色素及其开发应用

对原花色素的结构、化学特性、制备、分析方法、应用前景作一综述,并重点讨论其生理功能,为在功能性食品、药物、化妆品等领域的深入研究和开发提供参考。     

天然香精香料与生物技术

天然香精香料是高价值的精细化工产品和食品添加剂,但原料来源有限且提取成本高。利用生物技术生产这类产品具有广阔的前景。简述了发酵工程、酶工程、细胞工程和基因工程在香精香料中的应用,并探讨了生物技术在香精香料中的应用前景。     

毛霉型低盐速成豆豉工业化生产工艺与设备

本文介绍了毛霉型低盐速成豆豉的工业化生产工艺及生产线的关键设备。     

组学技术与果蔬采后质量和安全控制

果蔬可以提供营养, 有利于人类健康, 而果蔬的后熟及其与环境的相互作用会影响果蔬采后的质量和安全。对果蔬生物学过程的了解和掌握是减少果蔬采后损失和保障果蔬采后质量和安全的关键。在过去的10多年, 基于组学技术的系统生物学在了解果蔬后熟及其与环境相互作用的分子机制方面得到了越来越多的应用。本文对此做了细致的总结, 指出了存在的不足, 并提出了未来的发展方向。     

Heritability and correlations for body condition score and dairy form within and across lactation and age

The objectives of the current study were to investigate the relationship between body condition score (BCS) and dairy form and changes in genetic parameters for BCS and dairy form within and across lactations and age. Body condition score and dairy form were obtained from the Holstein Association USA, Inc. Records were edited to include those cows classified between 24 and 60 mo of age and between 0 and 335 d in milk (DIM). A minimum of 20 daughters per sire and 15 cows per herd-classification visit were required. The dataset consisted of 135,178 records from 119,215 cows. Repeatability, multiple trait, and random regression models were used to analyze the data. All models included fixed effects for herd-classification visit, age within lactations 1, 2, and 3 or higher, and 5th-order polynomials for DIM. Random effects included sire and permanent environment for all models. Random regression models included age at classification nested within sire or DIM and lactation number nested within sire. Genetic variance for both BCS and dairy form was lowest in early lactation and highest in midlactation. Genetic correlations within and across lactations were high. The genetic correlation between DIM 0 in lactation 1 and DIM 305 in lactation 3 was estimated to be 0.77 for BCS and 0.60 for dairy form. The genetic correlation estimate between 30 mo of age at classification and 50 mo of age at classification was 0.94 for both dairy form and BCS. The repeatability models appeared to generate accurate evaluations for BCS or dairy form at all ages and stages of lactation.