DMTD在Ti-DLC自配副摩擦界面的吸附及摩擦学行为的研究

采用非平衡磁控溅射技术制备了Ti掺杂的类金刚石(Ti-DLC)薄膜,用X射线衍射仪(XRD)和扫描电子显微镜(SEM)分别对薄膜结构和断面致密度进行了分析.用球盘式往复摩擦试验机考察了薄膜与以聚a-烯烃(PAO)为基础油,2,5-二巯基-1,3,4-噻二唑(DMTD)衍生物作为添加剂复合后的摩擦学性能,同时采用X射线光电子能谱(XPS)对摩擦后的磨痕进行元素分析,并进行动力学计算.结果表明:添加剂分子DMTD分子以巯基S作为吸附点吸附在摩擦界面,扩散是吸附的控制因素,吸附过程跟表面的覆盖度无关,符合Langmuir吸附模型.最后讨论了液体添加剂分子在DLC表面的吸附过程和气体分子吸附过程不同的可能原因.     

含硫化氢喷气燃料中噻二唑衍生物的缓蚀性能

研究了2,5-二巯基-1,3,4-噻二唑（ DMTD ）和5-甲基-2-巯基-1,3,4-噻二唑（ MMTD）在含H2 S喷气燃料中的缓蚀性能．银片腐蚀试验表明：对比未加剂喷气燃料,加入40 mg/L噻二唑衍生物后,银片的抗腐蚀性能显著增强．电化学测试表明：添加噻二唑衍生物明显降低了阴、阳极极化腐蚀电流密度,且MMTD的缓蚀效果优于DMTD．非接触式三维表面轮廓仪和扫描电子显微镜分别分析了银片在未加剂和加剂溶液中腐蚀表面,可明显的看出,噻二唑衍生物在银片表面形成了保护膜,有效阻止H2 S与银片的接触,从而减缓腐蚀．     

表面增强拉曼散射峰相对强度与温度的关系(英文)

用近红外傅立叶变换表面增强拉曼散射技术研究了 2 ,5_二巯基_1,3,4_噻二唑 (DMTD)在银表面的吸附与键合行为 .峰的相对强度随温度呈现出规律性的变化 ,表明DMTD异构体的相互转变或表面膜中DMTD分子的重新排布     

一种二相码信号多普勒补偿方法的研究与实现

针对相位编码信号脉冲压缩技术中存在的多普勒失配问题,提出并实现一种基于数字动目标检测(DMTD)的二相码信号多普勒补偿方法.该方法通过DM TD分离不同速度目标的回波,然后对不同速度通道的回波信号进行相应的多普勒补偿,矫正了多普勒失配问题.对速度模糊情况下的多普勒补偿进行了研究,进一步扩展了多普勒补偿的频率范围.该方法已应用于某新型雷达信号处理机的研制,其有效性得到证实.     

Synthesis of High Performance Thiophene–Aromatic Polyesters from Bio-Sourced Organic Acids and Polysaccharide-Derived Diol: Characterization and Degradability Studies

In this work, the feasibility of replacing petroleum-based poly(ethylene terephthalate) (PET) with fully bio-based copolyesters derived from dimethyl 2,5-thiophenedicarboxylate (DMTD), dimethyl 2,5-dimethoxyterephthalate (DMDMT), and polysaccharide-derived 1,6-hexanediol (HDO) was investigated. A systematic study of structure-property relationship revealed that the properties of these poly(thiophene–aromatic) copolyesters (PHS(20–90)) can be tailored by varying the ratio of diester monomers in the reaction, whereby an increase in DMTD content noticeably shortened the reaction time in the transesterification step due to its higher reactivity as compared with DMDMT. The copolyesters had weight-average molar masses (Mw) between 27,500 and 38,800 g/mol, and dispersity Đ of 2.0–2.5. The different polarity and stability of heterocyclic DMTD provided an efficient mean to tailor the crystallization ability of the copolyesters, which in turn affected the thermal and mechanical performance. The glass transition temperature (T_g) could be tuned from 70–100 °C, while the tensile strength was in a range of 23–80 MPa. The obtained results confirmed that the co-monomers were successfully inserted into the copolyester chains. As compared with commercial poly(ethylene terephthalate), the copolyesters displayed not only enhanced susceptibility to hydrolysis, but also appreciable biodegradability by lipases, with weight losses of up to 16% by weight after 28 weeks of incubation.     

The adsorption of 2,5-dimer-capto-1,3,4-thiadiazole (DMTD) on copper surface and its binding behavior

The interaction mechanism of 2,5-dimercapto- 1,3,4-thiadiazole (DMTD) on copper surface was studied by surface-enhanced Raman scattering (SERS), infrared (IR) and X-ray photoelectron spectroscopy (XPS) techniques. The SERS spectra were obtained. We found that DMTD bound with the copper via its two-excocyclic mercapto groups. The monosulphide salt was formed. At the same time, DMTD coordinated with the Cu⁺ ion through the excocyclic mercapto groups and polymerized via the Cu⁺ ion into a one- dimensional polymer chain on the copper surface.