稀土长余辉发光材料在纺织上的应用

介绍稀土长余辉发光材料的种类和发光原理,对发光纤维和印花发光织物的生产和产品性能做了简要描述,并对发光纺织品的应用现状进行了概述。     

静电纺制备稀土铝酸锶长余辉纤维膜的工艺研究

采用静电纺丝法制备了稀土铝酸锶长余辉纤维膜,详细介绍了纤维膜的制备过程、最佳的制备工艺,并对制得的纤维膜进行了表征。实验结果表明：纺丝液质量分数为10％-15％时,稀土铝酸锶长余辉发光材料浓度在5％～15％左右,纺丝电压为12～15kV,纺丝液流速在1．333ml／h左右,接受屏距离在l2cm左右,可制得性状良好的长余辉纤维膜。     

高速熔融纺丝中涤纶纤维的染色性能

1　前　言　　涤纶纤维是纺织工业中应用最为广泛的合成纤维之一。涤纶纤维传统的生产方法包括两道工序 :纺丝和拉伸。但在高速纺丝工艺中 ,这两道工序可以同步进行。涤纶纤维在高速纺丝的过程中会发生诱导取向结晶。结晶速度受高速纺丝条件的影响 ,如纺丝温度、卷绕速度、环境温度和熔融聚合物的挤压速度。因此 ,涤纶纤维的微结构可通过改变以上条件而得到控制。本文主要探讨通过高速熔融纺丝得到的具有不同结构的涤纶纤维的染色性能。2　实　验　　熔融聚合物从直径为 1 mm的喷丝头中以一定速度挤出后卷绕在位于喷丝头下 330 cm处的卷绕装…     

蓄光型稀土长余辉聚酯长丝的性能研究

研究测试了蓄光型稀土长余辉聚酯长丝的发光性能、断裂强力、断裂伸长和热收缩性能与稀土长余辉化合物添加量的关系。结果表明:随着稀土长余辉化合物添加量的增加,余辉性能显著提高,但断裂强力明显降低,断裂伸长提高,长丝的抱合力和可织造性能也降低。     

长余辉发光再生纤维素纤维的制备

对稀土铝酸锶长余辉粉末采用硅烷偶联剂进行包覆处理,增强了稀土铝酸锶粉末在水性溶液中的稳定性。以包覆处理过的稀土铝酸锶粉末为添加剂,以新型碱体系制备的再生纤维素为基材,通过湿法纺丝,制备出长余辉发光再生纤维素纤维。借助傅里叶红外光谱仪、扫描电镜、X射线衍射仪、单纤维强力测试仪、余辉亮度测试仪对样品的性能进行表征,结果表明:偶联剂通过化学键Si—O—Al包覆在稀土铝酸锶粉末上;经过偶联剂处理后,发光纤维的外观形貌较为光滑,直径约为60μm;纤维中稀土铝酸锶结构和纤维素Ⅱ结构同时出现,二者没有相互影响;纤维力学强度提高了10%;余辉初始亮度为0.82 cd/m~2。     

具光致变色功能的长余辉发光织物的制备研究

采用无水印花方法将1,3,3-三甲基-9'-羟基螺{2H-吲哚-2,3'-[3H]萘并[2,1-b](1,4)嗪}光致变色化合物处理到纯棉织物上,通过对其光致变色性进行检测和对比,筛选出了较适于制备光致变色织物的粘合剂为脂肪族聚氨酯PUI-112.通过先制备光致变色色浆而后采用类似于颜料印花的方法将其印在纯棉织物上,获得了很好的光致变色效果.研究并探讨了粘合剂种类、用量及焙烘条件和长余辉夜光印花浆的使用对光致变色效果的影响,确定了制备具光致变色功能的长余辉发光织物的最佳工艺.     

稀土硅酸镁锶聚丙烯夜光纤维的构相与余辉性能

采用高温固相法制备了Sr2MgSi207：Eu2+,Dy3+长余辉发光材料,并通过熔融纺丝制备出含有该发光材料的聚丙烯夜光纤维;对该夜光纤维的微观形貌、物相结构、光谱特征及余辉性能进行了测试和表征分析,结果显示,该纤维具有Sr2MgSi207：Eu2+,Dy3+发光材料和聚丙烯基材两者独立叠加的物相特征,激发光范围为250～450nm,能发出波长460nm的蓝色余辉,余辉初始强度大于600mcd/m2,寿命达7h,余辉衰减过程由快、慢两个阶段组成。     

纳米氧化锌改性锦纶6长丝的结构与物理性能北大核心CSCD

选用无机抗菌剂纳米氧化锌(ZnO)对锦纶6长丝改性,通过熔融纺丝法制备纳米ZnO改性锦纶6长丝(ZnO/PA6)。经对抗菌母粒结构与性能的分析,结果表明:ZnO质量分数5%时,ZnO均匀分散于抗菌母粒中,对黏度、灰分与熔点影响较小。经对ZnO/PA6结构与物理性能的分析,结果表明:当抗菌母粒中ZnO质量分数5%、抗菌母粒添加量5%时,ZnO/PA6的白色念珠菌、大肠杆菌与金黄色葡萄球菌抑菌率分别为92%、93%、99%,且ZnO均匀分散于ZnO/PA6中,对力学性能影响较小。     

聚酯纤维低聚物的存在、分析及最小化

着色聚酯纤维在进一步处理加工中的低聚物问题与纤维本身一样古老,至今仍未解决。到目前为止,由于聚酯纤维重要性的持续增长,已成为最重要的合成纤维,依据目前研究水平,应该弄明低聚物问题真相,采取实用分析技术,找出最有效的应对措施。本文正是这一目的,并且为后整理研究工作者了解、分析并控制低聚物提供一种手段。     

Mutant analysis reveals complex regulation of sphingolipid long chain base phosphates and long chain bases during heat stress in yeast

Sphingolipid long chain bases (LCBs) in Saccharomyces cerevisiae, dihydrosphingosine (DHS) and phytosphingosine (PHS) and their phosphates (DHS-P and PHS-P) are thought to play roles in heat stress. However, quantitative studies of LCBs and LCBPs have been limited by analytical methods. A new analytical procedure allowed us to measure changes in all known LCBPs and LCBs in wild-type and mutant cells during heat shock and to correlate the changes with heat stress resistance. All five molecular species of LCBPs increased rapidly but transiently when log and stationary phase cells were heat-stressed and when log-phase cells were induced for thermotolerance, suggesting that LCBPs play a role in heat stress. In support of this hypothesis, cells lacking the minor LCB kinase, Lcb5p, but not the major kinase, Lcb4p, were two-fold less resistant to killing when log-phase cells were induced for thermotolerance. Thus, LCBPs seem to play a minor role in heat-stress resistance. However, their role may be masked by LCBs, which are elevated in mutant strains, such as one lacking Lcb4p. This elevation demonstrates that one function of Lcb4p is to regulate LCB levels. Two new compounds, C(16) DHS and C(16) DHS-P, were identified, with the latter being degraded by the Dpl1p lyase. Our data provide a basis for determining how the basal and heat-induced levels of individual species of LCBs and LCBPs are governed by the Lcb4p and Lcb5p kinases, the Dpl1p lyase and the Lcb3p phosphatase.     

两个链状稀土配位聚合物的合成、结构及热动力学

采用水热法合成两个稀土羧酸配位聚合物{Ln(H2L)(HL)(H2O)}n,{H3L=5-(对羧苄氧基)-1,3-苯二甲酸;Ln=La(1)、Nd(2)}.通过元素分析,红外光谱以及X-射线单晶衍射分析确定配合物的晶体结构.根据普适积分法对配合物的热重图谱进行热动力学分析.结果显示,两个配位聚合物属同构物,均为三斜晶系,P-1空间群.与中心稀土离子参与配位的两个5-(对羧苄氧基)-1,3-苯二甲酸配体中,一个配体中有两个羧基氧参与配位,而另一个配体只有一个羧基参与配位;配位单元LnO9的空间构型为扭曲的三帽三棱柱结构.LnO9通过羧基氧原子桥联成一维链状结构,链状结构之间通过氢键形成三维网络结构.热重分析显示配合物有很高的热稳定性,普适积分法求出配合物两次失重过程的热分解动力学的三因子,并得出决定两个配合物失重过程反应速率的关键步骤为随机成核和随后生长机理.     

Distributions of brine and bacteria in beef primal cuts injected with brine without, or before or after mechanical tenderizing

Eye of round primal cuts of beef were injected with brines containing a dye and Listeria innocua. The amounts of brine in portions of meat were determined from the concentrations of dye in the tissues, and the numbers of L. innocua in the tissues were determined from the numbers of colonies recovered on hydrophobic grid membrane filters incubated on a selective agar. Portions of meat from primals injected with brine after extensive mechanical tenderizing yielded L. innocua at numbers that would be expected from the amounts of brine in the meat. However, portions of meat from primals injected with brine without or before mechanical tenderizing yielded only about 10% of the expected numbers of L. innocua. The numbers of L. innocua recovered from injected meat that was not tenderized, relative to the amount of brine retained by the meat, declined with decreasing brine pressure and increasing strokes per minute of the needle head. When brine was injected at about 5% with low brine pressure and high head speed, the numbers of L. innocua retained in the meat were <1% of the expected numbers. When injected meat was examined microscopically, L. innocua were observed only between the muscle fibres in meat that was not tenderized before injection, but between fibres and in lacunae in tissue damaged by mechanical tenderizing before injection. The distributions of brine and bacteria in injected primals apparently did not alter substantially during storage in vacuum packs, at 2°C, for 2 weeks.