微量pH电位滴定测定氨基酸、二肽和三肽与锌(Ⅱ)、镉(Ⅱ)配合物的稳定常数

His、Gly-His、Ala-His、Gly-Gly和Gly-Gly-Gly与锌、镉的配合物的稳定常数已有报道,由于不同作者的实验方法和数据处理方法不同,测定结果也不尽一致.有些数据是用手算方法进行数据处理的,求得的稳定常数可能不够精确.本工作采用文献推荐的微量pH电位滴定技术,对上述配体与Zn(Ⅱ)、Cd(Ⅱ)配合物稳定常数进行了测定.     

Immanant positivity for Catalan-Stieltjes matrices

We give some sufficient conditions for the nonnegativity of immanants of square submatrices of Catalan-Stieltjes matrices and their corresponding Hankel matrices. To obtain these sufficient conditions, we construct new planar networks with a recursive nature for Catalan-Stieltjes matrices. As applications, we provide a unified way to produce inequalities for many combinatorial polynomials, such as the Eulerian polynomials, Schröder polynomials, and Narayana polynomials.     

华北地磁测量

民国廿一年七月四日,至九月六日著者等偕助手唐復初,蒙中央研究院物理研究所及美国C.I.W.之地磁研究所之委托,分途至河北,河南,山西,陕西,张家口等处测验地磁之平横力,偏角,及倾角。茲蒙二所长之允许,特将尚未修改之结果露布,并附中西地名对照表以供参考(结果见本刊第九十一页至九十四页)。     

基于C^N^N三齿配体以及苯乙炔基或苯基的环金属化铂磷光络合物的比较研究（英文）

合成了两个系列的以2-芳基-6-(1H-砒唑-1-基)砒啶[芳基=苯基(L1),2,4-二氟苯基(L2),3,5-二甲基苯(L3),3-甲氧基苯基(L4),2-噻吩基(L5),2-苯并噻吩基(L6)]为环金属化配体,以苯乙炔基或苯基为辅助配体的铂化合物1a~6a和1b~6b.其中2b,3b和5b的结构用X射线晶体衍射方法进行了测定.结果表明,辅助基团苯基与配位平面采取一种扭曲的构型.Pt—C(苯基)键较Pt—C(炔基)键弱.对铂化合物的光物理性质包括吸收和发射光谱进行了研究.苯乙炔基取代的铂化合物1a~6a在室温溶液里发射较强的磷光,而苯基取代的确铂化合物1b~3b仅发射很弱的光.但是,化合物4b~6b发射比较强的光,尽管发光效率还是比相应的4a~6a低.这一现象表明4b~6b和4a~6a的激发态可能定域在三齿环金属化配体上.化合物1a~6a表现的较高发光效率可能是因为较强的和刚性的炔基配体.     

气相色谱法探究聚醚醚酮的热降解及热氧化降解（英文）

Poly(ether ether ketone)(PEEK)was synthesized via polycondensation of hydroquinone with 4,4′-difluorobenzophenone at 320℃for 5 h.Thermal and thermo-oxidative degradation of PEEK was studied over a wide range of temperatures.In an inert medium,decomposition of the polymer occurred in one stage,with the formation of a coke residue accounting for approximately 50%of the original polymer mass.In air,the mass loss curve exhibited two distinct stages.The first stage involved breakdown of the main polymer chain,the speed of which indicated a radical chain failure mechanism.In the second stage,the rate of mass loss clearly decreased,indicating a transition from the radical chain failure mechanism to simple combustion reactions(wherein the polymer combusted completely).To further investigate the nature of the processes occurring during the pyrolysis of PEEK,the investigations were carried out using gas chromatograph under isothermal conditions.It was concluded that during thermal degradation,the decomposition of the polymer starts with the rupture of ketone and ether bonds and proceeds to destruction of the benzene ring at higher temperatures,which is accompanied by the formation of H2O and CH4.Above 500℃,the polymer degradation further involved thermohydrolysis.The thermo-oxidation of PEEK,which was accompanied mainly by the formation ofH2,was noticeable beginning at 325℃.The total yield of the latter indicated oxidation of fragments of the benzene ring.     

单核锇配合物的合成、晶体结构及其与DNA的作用

使用溶剂热合成法,以p-bitmb配体(1,4-二(1-咪唑基-亚甲基)-2,3,5,6-四甲基苯)与[(η6-cymene)Os(μ-Cl)Cl]2或[(η6-bip)Os(μ-Cl)Cl]2为原料,合成了2种单核芳基锇配合物,并利用核磁、质谱、元素分析和X射线单晶衍射等手段对配合物进行了表征。配合物1属于单斜晶系,P21/c空间群,为一个单核锇的结构。中心锇原子与2个配体p-bitmb上的氮原子以及氯原子进行配位,2个配体的另一个咪唑基团通过一个亚甲基碳原子进行连接形成咪唑嗡离子,形成一个类似"碗"状的结构。一个氯离子通过氢键装载在结构的空腔内。利用核磁共振氢谱研究了结构中亚甲基的来源,并研究了配合物在缓冲溶液中的稳定性。用紫外吸收光谱、圆二色谱以及粘度法研究了配合物与DNA的相互作用,结果表明,配合物中的亚甲基来自于溶剂二氯甲烷。配合物以嵌入的方式与CT-DNA相互作用,结合常数分别为3.222×10~4 L·mol-1 (1)和1.53×10~4 L·mol-1 (2),同时配合物会减弱DNA的碱基堆积作用并可以使DNA发生解旋。     

Diamine anchored molecular junctions of oligo(phenylene ethynylene) cruciform

Using diamine as anchoring group, the self-assembled monolayers (SAMs) based on oligo(phenylene ethynylene)s (OPEs) and cruciform OPEs with an extended tetrathiafulvalene (TTF) (OPE3 and OPE3-TTF) were successfully formed on the Au substrate and then utilized in molecular junctions by conductingprobe atomic force microscopy (CP-AFM).     

Strong optical nonlinearities of self-assembled polymorphic microstructures of phenylethynyl functionalized fluorenones

The polymorphs of a phenylethynyl functionalized fluorenone derivative, and their controlled self-assembly for microstructures with different morphologies have been studied. These polymorphic microcrystals exhibit very distinctive NLO properties, which are highly correlated to their electronic and supramolecular structures.     

Methods for engineering therapeutic peptides

This review discussed recent advancements related to therapeutic peptide engineering.     

Red-emitting salicylaldehyde Schiff base with AIE behaviour and large Stokes shift

Three salicylaldehyde Schiff base (SSB) with AIE behavior were designed and facilely synthesized through a condensation reaction. In solid and aggregation states, these SSB dyes exhibited yellow to red emission with large Stokes shift. One of SSB dyes could specifically stain lipid droplets in living cells.