电荷转移配合物薄膜制备方法和结构表征的研究进展

回顾了与Langmuir-Blodgett(LB)技术有关的电荷转移配合物薄膜的各类制备方法、结构表征结果,并比较了制备方法对薄膜结构的影响.例如,将LB膜C18H37TCNQ(电子受体)插入到电子给体3,3’,5,5’-tetramethylbenzidine(四甲基联苯胺, TMB)的石油醚溶液中进行掺杂,制备了TMB•C18H37TCNQ电荷转移配合物薄膜.在这种薄膜中,给体和受体以面对面的方式堆积,两者的环平面与基片平面接近垂直.而采用硬脂酸和C18H37TCNQ的混合LB膜通过类似的掺杂路线制备的TMB•C18H37TCNQ薄膜的结构发生了一些变化,例如其长的烃链C18H37更加垂直于基片平面.通过比较以前的各种实验结果可以得出以下结论:电荷转移配合物的结构可以通过制备方法得到控制.     

聚(ε-己内酯)薄膜结晶形貌及分子取向研究

用匀胶机通过溶液铸膜方法在硅片和铝箔基板上分别制备具有不同厚度的聚(ε-己内酯)(PCL)薄膜. 通过原子力显微镜(AFM)和偏光衰减全反射傅里叶红外光谱(ATR-FTIR)对薄膜中PCL的结晶形貌、 片晶生长方式及分子链取向进行了研究. AFM结果表明, 在200 nm或更厚的薄膜中, PCL主要以侧立(edge-on)片晶的方式生长; 对于厚度小于200 nm的薄膜, PCL片晶更倾向于以平躺(flat-on)的方式生长. 这种片晶生长方式的改变在硅片和铝箔基板上都表现出同样的倾向. 此外, 在15 nm或更薄的薄膜中, PCL结晶由通常的球晶结构变为树枝状晶体. 偏光ATR-FTIR结果表明, 当膜厚小于200 nm时, 薄膜结晶中PCL分子链沿垂直于基板表面方向取向, 并且膜越薄, 取向程度越高, 与AFM的观测结果一致.     

2-烷基-苯并咪唑在硝酸银亚相上的Langmuir膜及LB膜

对不同链长的2-烷基-苯并咪唑衍生物（BzCn,烷基链长从C5到C15）在硝酸银亚相上的成膜行为及形成的LB膜的结构进行了研究.表面压－面积曲线的结果表明，短链(C5～C9)的2-烷基-苯并咪唑可在银离子亚相上形成稳定的单分子膜，而长链(C13和C15)衍生物则形成多层膜.利用LB技术可将上述Langmuir膜转移到固体基板上形成LB膜，其吸收光谱的结果说明了苯并咪唑和银离子配位.利用AFM、XRD及FT-IR等技术研究了烷基链长对LB膜结构的影响.实验结果表明,除了BzC15，其余的衍生物都可形成规整的层状结构.短链衍生物的单层LB膜具有均一、平整的形貌；而对于BzC15，观察到多层结构.     

两种不同取代结构C_(60)-苯乙烯共聚物薄膜微摩擦性能的研究

用自由基聚合法合成星状C6 0 苯乙烯共聚物和用原子转移自由基聚合法 (ATRP)合成单取代C6 0 苯乙烯共聚物 ,利用LB技术考察了它们的成膜性能并制备了多层薄膜 ,运用原子力显微镜 摩擦力显微镜(AFM FFM)初步研究比较这两种不同取代结构C6 0 苯乙烯共聚物薄膜的表面形貌和在极轻载荷下的微摩擦性能 .研究结果显示了星状C6 0 苯乙烯共聚物相对具有较好的润滑性能     

Cu掺杂TiO_2薄膜的摩擦学性能

采用溶胶-凝胶法在普通玻璃基底上制备了纯TiO2和Cu掺杂的TiO2(Cu-TiO2)纳米结构薄膜,利用X射线光电子能谱(XPS)、原子力显微镜(AFM)、粉末X射线衍射(XRD)及UMT-3摩擦磨损试验机考察了Cu掺杂量对薄膜组成、结构、表面形貌及摩擦学性能的影响.结果表明,相比于纯TiO2薄膜,Cu掺杂TiO2纳米薄膜平整、均匀,具有较好的耐磨减摩性能.Cu掺杂量的多少直接影响Cu-TiO2薄膜的减摩抗磨性能,当Cu掺杂量为5%(摩尔分数)时,Cu-TiO2膜具有最佳的耐磨寿命和最低的摩擦系数.     

聚3-羟基丁酸酯薄膜结晶的ATR-FTIR研究

使用匀胶机(spincoater),通过溶液铸膜的方法,在铝箔基板上制备出具有不同厚度的聚3羟基丁酸酯(PHB)薄膜.20℃室温条件下,通过衰减全反射傅立叶红外光谱(ATRFTIR)原位观测了不同厚度薄膜的结晶过程,并通过偏光ATRFTIR对薄膜中PHB分子的取向进行了研究.ATRFTIR原位观测结果显示,PHB在薄膜中的结晶速率以及结晶度均随着薄膜厚度的减小而逐渐降低;同时,偏光ATRFTIR测试结果表明,随膜厚减小,薄膜中结晶部分的PHB分子逐渐倾向于沿垂直于基板表面方向取向,膜越薄,倾向越明显.可以认为,PHB分子与基板间的相互作用以及扩散控制结晶导致了上述现象的产生.     

非两亲性四硫代富瓦烯导电LB膜的研究

近年来，利用LB技术制备电活性的有机超薄膜受到广泛的关注．导电LB膜的膜材料主要是含有受体化合物7，7’，8，8’-四氰基二亚甲基苯醌（TCNQ）的电荷转移复合物[1~3]以及给体分子[4，5]，特别是四硫代富瓦烯（TTF）衍生物[6~8]．尽管LB膜多由带长链的两亲性分子组装而成，但是对非两亲性TTF衍生物LB膜的研究[9~11]结果表明，引入长链烷基并非制备TTF类电荷转移复合物LB膜的先决条件．该结果极大地拓展了LB膜材料的研究范围．本文报道非两亲性TTF衍生物与花生酸混合导电LB膜的制备、结构表征与导电性能研究．1实验部分利用亚磷…     

Langmuir-Blodgett方法构建聚合物仿细胞外层膜结构涂层

以盖玻片为基质,采用Langmuir-Blodgett(LB)方法制备含磷酰胆碱基团的两亲性无规共聚物聚(2-甲基丙烯酰氧基乙基磷酰胆碱(MPC)-甲基丙烯酸十八烷基酯(SMA)-γ-甲基丙烯酰氧丙基三甲氧基硅(TSMA)(简称PMST)的单层、双层和三层薄膜.薄膜的表面亲疏水性和表面形貌分别用动态接触角(DCA)和原子力显微镜(AFM)进行测试.结果表明,PMST在盖玻片表面形成了致密的膜层,薄膜的致密程度随层数而增加.在水中前进/后退测试DCA过程中,聚合物薄膜在气相/水相界面存在基团的迁移取向,且膜层内会发生交联.双层膜具有仿细胞外层膜结构,单层和三层膜具有反细胞外层膜结构;双层膜的亲水性比单层和三层膜的要好.     

溶胶-凝胶-水热晶化法制备锐钛矿TiO2纳米膜的耐蚀性能

以钛酸正丁酯为前驱体, 采用溶胶-凝胶-水热晶化法在不锈钢(SS)表面制备TiO₂纳米膜. 利用X射线衍射(XRD)、Raman光谱、场发射扫描电子显微镜(SEM)、原子力显微镜(AFM)和俄歇电子能谱(AES)表征了TiO₂纳米膜的晶型、表面形貌和表面化学组成. 通过极化曲线和电化学阻抗谱(EIS)研究了TiO₂纳米膜的耐蚀性能. 170 °C下水热晶化制备的锐钛矿TiO₂与450 °C焙烧制备的锐钛矿TiO₂的结晶度类似, 但两种TiO₂薄膜的表面结构存在明显差异, 水热晶化法制备的TiO₂纳米膜在3.5% (w) NaCl溶液中的耐蚀性能优于焙烧法制备的.     

聚酰亚胺LB膜真空热解制备β-SiC膜的STM观察

扫描隧道显微镜 ( STM)是一种基于量子隧道效应对样品进行高分辨无损测试的表面测试技术 [1] ,它可以在原子水平上反映表面分子或原子的排列分布情况 ,在物理、化学、生物和微电子界受到高度的重视 .STM技术以及其后发展起来的原子力显微镜 ( AFM)特别适合 LB膜的研究 ,能直观地反映出 LB膜中分子排列的微观结构以及表面缺陷 [2 ,3] .我们曾通过真空热解沉积在单晶硅片上的聚酰亚胺L B膜制得了准单晶β- Si C超薄膜 [4～ 6 ] .本文利用 STM技术对聚酰亚胺 LB膜以及由它真空热解而成的 Si C膜的表面形态结构进行了初步观察和分析 .…     

Synthesis and structure of hydroxyisoxazolidines and derivatives of hydroxylamine and alkenals

The reactions of N-substituted hydroxylamines with alkenals serve as a method for the synthesis of the corresponding 2-substituted 3(5)-hydroxyisoxazolidines. The reaction pathway is determined by the nature of the substituent attached to the nitrogen atom. Ring-chain isomerism has been detected in these newly obtained compoundsTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1270–1276, September, 1987.     

红霉素9,11-亚胺醚和乙腈分子加合物的合成和晶体结构

通过控制红霉素A (E)肟的贝克曼重排反应条件合成了一种关键中间体红霉素9,11-亚胺醚, 该化合物可与乙腈形成稳定的分子加合物(摩尔比为1∶1), 未见文献报道. 阐述了该化合物的合成、晶体结构、晶体学数据和结构参数. 该化合物为无色透明晶体, 属单斜晶系, 空间群P2₁. 对该加合物和已知化合物红霉素6,9-亚胺醚晶体结构的对照解析, 有助于对重排反应机理、异构化机理和两异构体还原差异性的分析, 对重排反应和还原反应起到积极的指导作用.     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

Sizes of atoms and ions and covalency of bonding in molecules and crystals

A new system of atomic radii for the elements up to barium inclusive is constructed. Values of the radii are chosen so as the dependence between the dissociation energy of diatomic homonuclear molecules and a depth of atom overlapping is monotonous, and the scatter of data is minimal. The depth of overlapping is calculated as a difference between the sum of atomic radii and an experimental interatomic distance. Conclusions are made that: the radii of free atoms and ions are determined by the value of the electron density equal to 0.01 au; they considerably change in molecules and crystals only as a result of the charge transfer from cation to anion; covalent bonding is well described by the overlapping of free atoms (ions), confined by the surface of the given radius, and its energy depends upon the depth of overlapping of valence electron densities of atoms. A method of overlapping atoms is proposed for the approximate estimation of ionic sizes and charges in bound systems.     

四环素-铕与卵磷脂的相互作用及卵磷脂的测定

以四环素(TC)-Eu3 作为荧光探针,提出了新的荧光光度法测量卵磷脂(PC)。在pH 5.7的酸度条件下,扫描不同浓度的PC与TC-Eu3 的荧光光谱。通过优化实验条件,得到了测定PC的最佳条件。卵磷脂能使TC-Eu3 位于612 nm处的特征荧光显著增强且增强的荧光强度与PC的量成正比。测量的线性范围为4.0×10-7~1.4×10-5mol/L,检出限为3.9×10-8mol/L。该方法已用于实际样品的测定。     

Synthesis and Characterization of Chloralose-Derived Thiosemicarbazones and Semicarbazones and Investigation of Their Antimicrobial Properties

Thiosemicarbazones(7–10)/semicarbazones(11–14) were synthesized in good yields via the condensation of α-gluco-, β-gluco-, galacto-, manno- chloralose derived 1,4-furanodialdoses (1-4) with thiosemicarbazide(5)/semicarbazide(6). The structures of all products were characterized by FTIR, NMR spectroscopic methods and elemental analysis. The compounds have been found to display moderate antimicrobial activity against Gram-positive, Gram-negative bacteria and antifungal activity against a Candida albicans. MIC values of the compounds range from 260 to 1510 μg/mL.     

Resurrection and Reactivation of Acetylcholinesterase and Butyrylcholinesterase

Organophosphorus (OP) nerve agents and pesticides present significant threats to civilian and military populations. OP compounds include the nefarious G and V chemical nerve agents, but more commonly, civilians are exposed to less toxic OP pesticides, resulting in the same negative toxicological effects and thousands of deaths on an annual basis. After decades of research, no new therapeutics have been realized since the mid-1900s. Upon phosphylation of the catalytic serine residue, a process known as inhibition, there is an accumulation of acetylcholine (ACh) in the brain synapses and neuromuscular junctions, leading to a cholinergic crisis and eventually death. Oxime nucleophiles can reactivate select OP-inhibited acetylcholinesterase (AChE). Yet, the fields of reactivation of AChE and butyrylcholinesterase encounter additional challenges as broad-spectrum reactivation of either enzyme is difficult. Additional problems include the ability to cross the blood brain barrier (BBB) and to provide therapy in the central nervous system. Yet another complication arises in a competitive reaction, known as aging, whereby OP-inhibited AChE is converted to an inactive form, which until very recently, had been impossible to reverse to an active, functional form. Evaluations of uncharged oximes and other neutral nucleophiles have been made. Non-oxime reactivators, such as aromatic general bases and Mannich bases, have been developed. The issue of aging, which generates an anionic phosphylated serine residue, has been historically recalcitrant to recovery by any therapeutic approach—that is, until earlier this year. Mannich bases not only serve as reactivators of OP-inhibited AChE, but this class of compounds can also recover activity from the aged form of AChE, a process referred to as resurrection. This review covers the modern efforts to address all of these issues and notes the complexities of therapeutic development along these different lines of research.     

Ni(Ⅱ)和Zn(Ⅱ)的乙基黄原酸盐与吡啶碱配合物的合成及性质的研究

乙基黄原酸基的结构为:(简写为Exan,它是一个双齿配体,能和许多金属离子形成稳定配合物。 本文依据实验结果,对3种Ni(Ⅱ)和2种Zn(Ⅱ)的乙基黄原酸盐混合配合物的性质作一些系统的比较.应用红外光谱讨论这些混合配合物的C—O及C—S键振动频率位移;用热谱讨论它们的热稳定性及失重过程的变化;通过组成分析用电子光谱及磁学方     

Nucleophilicities and Nucleofugalities of Thio- and Selenoethers

Rate constants for the reactions of dialkyl chalcogenides with laser flash photolytically generated benzhydrylium ions have been measured photometrically to integrate them into the comprehensive benzhydrylium-based nucleophilicity scale. Combining these rate constants with the previously reported equilibrium constants for the same reactions provided the corresponding Marcus intrinsic barriers and made it possible to quantify the leaving group abilities (nucleofugalities) of dialkyl sulfides and dimethyl selenide. Due to the low intrinsic barriers, dialkyl chalcogenides are fairly strong nucleophiles (comparable to pyridine and N-methylimidazole) as well as good nucleofuges; this makes them useful group-transfer reagents.     

手性联萘酚的多胺缀合物的合成与表征

以N1-氨基丁基-N1,N4-二叔丁氧羰基-1,4-丁二胺和手性甲酰基联萘酚为原料,经缩合后用NaBH4还原,产物提纯后脱保护,得到目标产物S-6和R-6,所得化合物的结构均经IR、1H NMR、13C NMR和MS测试确认.