铬的污染源及其危害

本文介绍了铬污染的来源并对其危害进行了分析和讨论，从而说明了治理铬污染的必要性和重要性。     

Compatibility and Properties of Biodegradable Blend Films with Gelatin and Poly（vinyl alcohol）

The blend films with gelatin and poly（vinyl alcohol） （PVA） were prepared by a solution casting method. The compatibility between gelatin and PVA in the blend films was investigated. The transmittance, Fourier-transform infrared spectroscopy （FTIR）, x-ray diffraction （XRD）, thermogravimetry analysis （TG）, and differential scanning calorimetry （DSC） were employed to characterize the resultant blend films. According to optic result, the opacity of the blend film at the ratio of 20/80 （w/w, Gel to PVA） was the lowest, indicating the best compatibility between Gel and PVA at the ratio. The results oflR, XRD, DSC, and TG revealed an intensive interaction and good compatibility between them in the blend film at the ratio. The mechanical properties and solubility showed that PVA content in the blend films obviously affected the elongation at break and solubility. The mechanical properties and water resistance of gelatin film may be improved by the introduetion of PVA.     

影响胶原结构与性能的因素研究进展

胶原及胶原基材料广泛应用于生物医用、皮革、食品、日用化学工业等领域。在加工、应用及保存的过程中,胶原常会受到光照、温度及湿度变化、pH值变化、盐溶液浸泡以及细菌和霉菌侵蚀等作用,使材料的结构发生改变,导致性能变化。本文综述了引起胶原结构与性能变化的主要因素,阐述了紫外光照射、酸与碱溶液、盐溶液与有机溶剂及热作用下,胶原的热稳定性能、三股螺旋链结构及聚集态结构的变化。     

环保染色载体OE在涤纶常温染色中的作用及应用

为了降低涤纶织物的染色温度,实现节能环保染色,研究了环保载体OE在涤纶织物上的染色性能及染色工艺.结果表明:环保载体OE对涤纶纤维具有增塑作用,能有效降低涤纶的染色温度,在98℃染色时,染液中加入载体OE与不加载体相比,染色速率和上染百分率显著提高;染料用量为2%(o.w.f)时,载体OE的最佳用量为6%(o.w.f)...     

紫外照射对胶原黄变及结构的影响北大核心

以胶原溶液为研究对象,探索紫外照射(UV)对皮胶原黄变及溶液性质的影响。通过白度仪、紫外可见分光光度计、乌氏黏度计、X-射线衍射等表征手段,对紫外照射前后胶原溶液的物理化学性质进行研究。结果表明:紫外照射可使胶原分子链中的芳香族氨基酸被破坏,导致胶原产生黄变行为,胶原黄变程度随照射时间的延长而增加;胶原溶液黏度随紫外照射时间的增加呈现下降趋势,照射时间大于4h,胶原溶液黏度呈现急剧降低趋势;紫外照射32h后,胶原三股螺旋结构的特征衍射峰消失。结合紫外光作用下胶原黄变情况及其结构变化,证明胶原明显黄变行为主要发生在其三股螺旋结构被严重破坏的阶段。     

皮革中甲醛的研究进展

从皮革中甲醛的危害、来源、检测方法和治理措施方面综述了其研究进展,指出皮革中甲醛主要来源于有机合成鞣剂、固定剂、涂饰剂等化学品,可以通过物理及化学方法去除。并探讨与展望了皮革中甲醛的研究趋势．提出加强不舍及不产生甲醛等有害物质的替代皮革化学品的研制与开发十分必要。     

Electrospinning and rheological behavior of poly (vinyl alcohol)/collagen blended solutions

Poly(vinyl alcohol)/collagen (PVA/COL) micro-nanofibers were successfully prepared by electrospinning process. Water, green, and non-toxic was used as the solvent. The electrospun mats consisted of micro-nanoscale fibers with mean diameter ranging from approximately 363 nm to 179 nm. It was observed that the mean diameters of PVA/COL electrospun fibers decreased with increasing collagen content. The effects of PVA/COL blending ratio on the rheological behavior of PVA/COL blended solutions were investigated by rotate rheometer. It was found that PVA/COL blended solutions behaved as Non-Newtonian fluids. With increasing collagen content, the Non-Newtonian index (n) of PVA/COL blended solutions decreased. Meanwhile, a linear relationship was found between the Non-Newtonian index (n) and the mean diameters of the PVA/COL micronanofibers. The chemical structures of PVA/COL electrospun fibers were also characterized by FTIR.     

汗液对皮革耐热稳定性的影响

采用热台显微镜、热重分析等方法研究了未鞣制皮粉、铬鞣皮粉和戊二醛鞣制皮粉的热收缩和热降解行为，探索了这些试样在受到汗液浸泡作用时热收缩和热降解行为方面所发生的变化，讨论了发生这些变化的机理。     

皮胶原纤维吸附水分动力学

研究了皮胶原纤维对水分的吸附行为。结果表明,皮胶原纤维吸附水分一般在9h后就基本达到平衡,环境湿度越大,达到吸附平衡所需的时间越长。采用Lagergren一级速率模型和二级速率模型分别拟合了皮胶原纤维吸附水分的实验数据,发现二级速率模型与实验数据比较吻合。颗粒内扩散模型的分析结果表明,皮胶原纤维吸附水分的过程包含三个相对独立的阶段,各阶段的吸附速率分别受不同因素的控制。