Zn（Ⅱ）与巯基苯并噻唑的次磺酰胺衍生物配合物的合成

本文介绍了Ｚｎ（Ⅱ）与巯基苯并噻唑的次磺酰胺衍生物ＤＭ、ＣＺ的配合物的合成，并进行了ＩＲ、ＵＶ、元素分析等表征研究，指认所合成的化合物为［Ｚｎ（ＤＭ）ＣＬ＿２］（简称ＺＤＭ）、［Ｚｎ（ＣＺ）＿２ＣＬ＿２］（简称ＺＣＺ）。     

Assembly of MHC class I peptide complexes from the perspective of disulfide bond formation

Assembly of functional major histocompatibility complex (MHC) class I peptide complexes within the endoplasmic reticulum is critically important for the development of an adaptive immune response. The highly regulated loading of peptides onto MHC class I molecules is controlled by a multi-component chaperone system called the MHC class I peptide loading complex. The recent identification of the thioredoxin family member ERp57 as a component of the loading complex led to an interesting question: Why is there a thiol-disulfide oxidoreductase inside a complex dedicated to inserting peptides into a receptor binding site? Most recently, specific ERp57-mediated disulfide bond rearrangements have been identified inside the loading complex. What these biochemical events mean for the peptide loading process remains a matter of conjecture. While several important questions wait to be answered, this review intends to summarize our current view of the oxidative folding of MHC class I molecules and addresses the question of how the receptor ligand interaction might be regulated by thiol-based redox reactions.     

POM基MoS_2自润滑复合材料的真空摩擦学特性研究

分别用前驱体分解法与剥层重堆法制备出二硫化钼纳米球(nano-MoS2)与聚甲醛/二硫化钼夹层化合物(MoS2-IC),再利用制备的nano-MoS2、MoS2-IC与微米二硫化钼(micro-MoS2)作为原料制备出POM/MoS2复合材料.在真空摩擦磨损试验机上考察了复合材料的摩擦学性能,结果表明,POM/nano-MoS2复合材料具有最好的摩擦学性能,POM/MoS2-IC复合材料次之,而POM/micro-MoS2复合材料性能与POM比没有改善;SEM分析显示,POM及其复合材料主要发生的是疲劳磨损,POM/nano-MoS2的疲劳磨损最轻,POM/MoS2-IC疲劳磨损最严重,POM与POM/micro-MoS2除了疲劳磨损外,还存在明显的粘着磨损.     

Preparation of Ln3-xEuxS4 （Ln=Ce,Pr, and Nd） ceramics by pressureless sintering

The preparation of ternary rare earth sulfides of Ln3-xEuxS4 （Ln = Ce, Pr, and Nd） ceramics was investigated, and the effect of Eu substitution on Ln3-xEuxS4 ceramics was also studied. Ln3-xEuxS4 powders were synthesized by the sulfurization of their oxide powders using carbon disulfide gas. Ln3-xEuxS4 ceramics were sintered by pressure-less sintering method. All pressureless sintered Ln3-xEuxS4 ceramics crystallized in y-phase. It was found that Eu substitution could improve the density of Ln3-xEuxS4 ceramics. Furthermore, Eu substitution might narrow the optical band gaps of Ln3-xEuxS4 ceramics.     

从生产促进剂M废树脂中制取促进剂DM

以工业生产促进剂M的废树脂为原料,经过打浆,甲苯萃取、碱溶解、双氧水氧化合成了促进剂DM,平均收率8.3%,初熔点167.1℃,达到国标(GB11408-89)一等品标准.考察了不同分散剂对制备促进剂DM收率的影响,挑选脂肪酸聚氧乙烯酯(99#)作为分散剂,考察反应温度、双氧水滴加时间、反应时间等因素对合成促进剂DM的影响,找到合成促进剂DM的最佳工艺条件:反应温度60℃,双氧水滴加时间40min,反应时间2h,分散剂、双氧水、EDTA的质量分数分别为1%,27%,5%,M的质量浓度为0.15g/mL.     

还原型牛胰岛素在疏水界面上的折叠

用疏水色谱（ＨＰＨＩＣ）对还原变性的牛胰岛素在疏水界面上的折叠规律进行了探讨,对于未来原的胍变和脲变ｉｎｓｕｌｉｎ来说,胍变ｉｎｓｕｌｉｎ用ＨＰＨＩＣ法可以完全复性,而脲变ｉｎｓｕｌｉｎ只能部分复性。对于还原变性的ｉｎｓｕｌｉｎＨＰＨＩＣ对胍变、脲变ｉｎｓｕｌｉｎ只能部分复性。在非氧化型流动相中,它们的复性情况较差,而采用氧化型流动相,有助于二硫键的正确对接,可大大提高胍变和脲变ｉｎｓｕｌｉｎ的复     

酸性镀锡液稳定剂的优选

本工作采用加热恒温氧化法、鼓气氧化法和Ｈ＿２Ｏ＿２加速氧化法，研究了酸性镀锡液稳定剂：ＦＳ－１、ＦＰ－型和铈离子（Ｃｅ（４＋））对硫酸型光亮镀锡液的基础镀液稳定性的影响。实验结果表明，稳定剂的稳定效力ＦＳ－１优于ＦＰ－型稳定剂，Ｃｅ￣（４＋）也有一定的稳定作用。由于铈离子还能提高镀锡层的可焊性和抗氧化性、抗腐蚀性能，因此，我们认为：ＦＳ－１＋Ｃｅ￣（４＋）是目前硫酸型光亮镀锡液的最佳组合稳定剂。     

SnO2/n-Si双层结构的湿度敏感性及其物理机制*

在室温下利用直流磁控溅射方法在硅基底上制备了二氧化锡薄膜,得到Sn O2/n-Si双层结构。利用扫描电子显微镜对二氧化锡薄膜的结构进行表征、分析。通过测量双层结构在干燥及湿度环境中的伏安特性,研究了其湿度敏感性。结果表明:双层结构在干燥和湿度环境中均表现出二极管特性,且从干燥环境向湿度环境过渡时,该结构在正向偏压下电流变化明显。基于该结构正向偏压下的伏安特性研究其湿度敏感性,研究发现双层结构在工作电压为0.25 V时,湿度灵敏度最佳。灵敏度随着环境湿度的增大而增大,在相对湿度为67%时,灵敏度达到142%,响应时间和恢复时间分别为550 s和240 s。最后,基于能带理论,揭示了双层结构湿度敏感性的物理机制。该研究对湿度传感器的开发具有一定的指导意义。     

Ultrafast dynamics and dissociative ionization of CS<Subscript>2</Subscript> molecules studied via the femtosecond pump-probe method

The ultrafast dynamics and dissociative ionization of CS2 were studied using the pump-probe method with time-of-flight mass spectroscopy. The transient behavior of both parent ion (CS2+) and fragment ions (S+ and CS+) was observed. It was found that all the ionic signals decay exponentially with lifetimes that were different for delay times, t>0 and t<0, which can be attributed to the evolution of different Rydberg states pumped by 267-nm and 400-nm laser pulses. The lifetimes of two Rydberg states were obtained simultaneously from one fitting of the transients. The fragment ions were produced by the dissociation of CS2+, and it is suggested that the final ionic state is the C2Σg+ state of CS2+ based on the measured S+/CS+ branching ratio. The S+/CS+ ratio is dependent on the delay time of the two lasers, indicating that the dissociation process of CS2+ is related to the evolution of the intermediate Rydberg state.