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1.
Two new Hofmann-type complexes, M (1,3-thiazolidine-2-thione)2 Ni(CN)4 (where M = Ni and Cd), were synthesized and characterized by elemental analysis, magnetic susceptibility data, IR and Raman Spectroscopy. Their structure consist of planar infinite polymeric layers of {M-NI(CN)4}∞. 1,3-thiazolidine-2-thione coordinated to M atom above and below this layers is monodentate and S-bonded in these complexes.  相似文献   

2.
ABSTRACT

New Hofmann–Td-type clathrates of the forms Cd(CPA)2M(CN)4.C6H6 (CPA = cyclopropylamine; M?Cd or Hg) prepared in powder form and characterized by FT-IR, FT-Raman, far-IR spectra, X-ray diffraction, and elemental analyses are reported. Vibrational assignments are proposed for the bands of the host lattice and guest molecule. It is shown that the spectra are consistent with a proposed crystal structure for the compounds derived from X-ray diffraction measurements. The C, H, and N analyses were carried out for all the compounds. All the vibrational modes of coordinated CPA are characterized. The spectral features suggest that these compounds are similar in structure to the Hofmann–Td-type clathrates.  相似文献   

3.
Infrared and Raman spectra of seven new metal (II) 3,4-lutidine tetracyanonickelate complexes, M(3,4 L)2 Ni(CN)4 [where 3,4 L = 3,4 - dimethyl-pyridine or 3,4-lutidine; M = Mn, Fe, Co, Zn, Ni, Cu or Cd] (abbreviated to M - Ni - 3,4 L) have been investigated. Spectroscopic and magnetic susceptibility measurements indicate that the compounds have the structure of Hofmann-type complexes. The copper complex has spectral features different from the other compounds.  相似文献   

4.
The characteristic changes in UV-visible and Raman spectra of lithocholic acid on E-2-Butenal for antiglioma are the maximum absorption peak of E-2-Butenal from 302 to 319 nm, the decreases of Raman signal of 1688 cm?1 and 1641 cm?1 in E-2-Butenal by lithocholic acid with the phenomenon of 1688 cm?1 splitting, and the disappearance of the band at 932 cm?1, which clearly displays the change of wagging in methyl. In the presence of mitochondrial protein deriving from glioma, the above mentioned effects of lithocholic acid on E-2-Butenal are more significant by Raman spectra detections. The molecular targets of lithocholic acid on E-2-Butenal are carbonyl group, conjugated double bonds, and methyl, respectively. The study concludes that the interaction between lithocholic acid and E-2-Butenal decreases the carbonyl group bond strength in E-2-Butenal and then changes the structure and function of E-2-Butenal. The internal cause of the interaction between lithocholic acid and E-2-Butenal leading to the change of the carbonyl group bond strength is the electronic delocalization near the carbonyl group bond in E-2-Butenal. Since E-2-Butenal derives from glioma in the process of lipid peroxidation of mitochondria, our investigation significantly contributes to understanding the mechanism of action of lithocholic acid as a potential antiglioma drug.  相似文献   

5.
Fast atom bombardment mass spectrometry (FAB-MS) and high resolution (400 Mz) proton nuclear magnetic resonance (NMR spectroscopy) on the competitive angiotensin II antagonist, |Sar1, Tyr(Me)4 (ANGII (Sarmesin) and its he-ptapeptide homolog, [Tyr(Me)3 |ANGIII, yield spectra which provide confirmation of structure and molecular weight. The characteristics of the spectra are discussed and compared with the spectra of natural ANG II, ANG III and |Sar1|ANG II. The NMR data are suggestive of interactions in angiotensin between: 1) the phenolic hydroxyl group and the imidazole ring, and 2) the N-terminal amino group and the Tyrring. These interactions may be important for the formation of the proposed charge transfer system in angiotensin II involving the phenoxyl and α-carboxylate groups.  相似文献   

6.
光谱法研究普利沙星与小牛胸腺DNA的结合作用   总被引:2,自引:1,他引:2  
利用紫外光谱,荧光光谱及流体动力学方法,研究了普利沙星与小牛胸腺DNA的作用机理。讨论了不同浓度普利沙星与DNA作用的紫外光谱,荧光光谱,磷酸盐效应以及离子强度对两者相互作用的影响,测量了DNA的热变性温度和粘度。从紫外光谱图上看出DNA发生了明显的减色效应, 说明普利沙星可能与DNA发生作用。普利沙星的荧光光谱发生了有规律的猝灭,最大发射峰发生红移, 猝灭常数为3.1×104 L·mol-1, 为静态猝灭,表明普利沙星与DNA结合生成了二元复合物。磷酸盐效应表明普利沙星与DNA的磷酸基团不发生静电作用。普利沙星引起了DNA的热变性温度略微升高(≤7℃)和DNA粘度略微下降, 表明普利沙星与DNA之间不存在插入作用, 只是在DNA的外部发生沟槽作用。  相似文献   

7.
The ESI and FAB mass spectral fragmentations of seven bis-quinolizidine alkaloids were investigated. Fragmentation pathways, elucidation of which was assisted by FAB/CID mass spectra measurements, are discussed. The data create the basis for distinguishing stereoisomers and metamers.  相似文献   

8.
氧化低密度脂蛋白(oxidized low density lipoprotein,oxLDI)被认为是动脉硬化的关键致病因素.文章综合运用紫外吸收光谱、荧光光谱、同步荧光光谱及圆二色(circular diclaro‘lsm.CD)光谱研究了(好'诱导不同时间的U)IJ体外氧化过程.随着氧化时间的增加.生成的丙二醛(malonaldehyde,MDA)的量逐渐增加,其相对应的430 nm 处的荧光强度也随之加强,氧化过程中生成了新的氧化产物.氧化低密度脂蛋白紫外吸收增强;表征氨基酸残基信息的特征荧光强度和同步荧光强度降低;载脂蛋白B-100(apolipoproteinB-100,apoB-100)α-螺旋含量减少.实验结果表明,LDL氧化过程中Cu2+不仅诱导了氧化产物的生成,而且改变了apoB-100的构象进而导致了生色基团的微环境的变化.  相似文献   

9.
The complexes [Coiii(LH2)3]X3 (LH2 = dithiooxamide, N-methyldithiooxamide, N,N′-dimethyldithiooxamide; X = Cl, Br, l) and [CoiiL]n have been prepared. They were characterized by analyses, thermal techniques, magnetic susceptibilities and spectroscopic (ligand-field, 13C-NMR, FT-IR) methods. The vibrational analysis of the prepared complexes is given using NH/ND and CH3/CD3 isotopic substitutions. The neutral dithiooxamides exhibit a bidentate chelating S,S-coordination, while the doubly deprotonated dithiooxamido anions act as bis-bidentate bridging S,N/N,S-ligands giving trans polymeric structures. The Co(III) complexes are octahedral with CoIIIS6 coordination spheres. A square planar geometry around Co(II) is assigned for the polymeric compounds.  相似文献   

10.
含纳米棒银溶胶的制备及其光谱性质研究   总被引:1,自引:0,他引:1  
以CTAB表面活性剂胶束为模板用化学还原法制备出含有银纳米棒的银胶体,用透射电镜(TEM)对颗 粒形貌进行了表征.UV Vis吸收谱显示,含银纳米棒溶胶有两个吸收蜂,其中长波长吸收峰位置随胶粒长径比增 加迅速红移和宽化.用多尺寸统计平均的Mie散射模型计算了纳米棒银胶体的吸收谱,较好地解释了长波长吸收 峰的宽化.以此胶体为衬底材料,测量了染料分子的表面增强拉曼散射(SERS),结果显示,SERS强度随胶体中 所含纳米棒长径比的增加呈现先显著增强后缓慢减弱的变化规律,用电磁增强理论对有关现象进行了分析.  相似文献   

11.
The contributions of the M++ and (M - Het·)+ ions in the mass spectra of bipyridyl and biquinolyl derivatives have been determined. Studies were also made of triply charged molecular ions and of the mass spectrum of 8,8′-biquinolyl.  相似文献   

12.
人肺组织与肺癌组织FTIR光谱的统计分析   总被引:4,自引:1,他引:3  
本文应用统计方法分析了人肺正常组织和肺癌组织的FTIR光谱 ,选择光谱谱型参数 ;峰位、峰高、峰位差、峰高比进行比较分析 ,发现有多个变量可以显示两类光谱的差异 ,选择峰高比参数建立了Logistic预测方程为光谱的应用进行了探索。结果表明可以借助数学方法对组织光谱进行数据转换和分析 ,为了研究大量的组织光谱提供思路。  相似文献   

13.
本文用拉曼光谱法测定了天花粉蛋白在pH为1.9~11.5范围内二级结构的变化。结果表明,随pH值的增加,α-螺旋略有减少,β-折叠略有增加,而无序结构没有明显变化。  相似文献   

14.
钨酸钇钠晶体中Tm3+的光谱特性   总被引:4,自引:2,他引:2       下载免费PDF全文
测量了Tm3 :NaY(WO4 ) 2 晶体的吸收光谱、发射光谱和激发光谱 ,利用J_O理论计算了钨酸钇钠晶体的强度参数 :Ω2 =7 2 130 4× 10 - 2 0 cm2 ,Ω4 =0 5 0 4 76 6× 10 - 2 0 cm2 ,Ω6 =0 977784× 10 - 2 0 cm2 ,以及Tm3 的光学参数包括各能级的荧光寿命和荧光分支比、积分发射截面等 ,在计算了Tm3 的自发辐射概率时 ,同时考虑了电偶极跃迁和磁偶极跃迁 .研究了其发光特性和跃迁通道 ,发现存在1 D2 3H6 →1 G4 3F4 的交叉弛豫  相似文献   

15.
用高温共焦显微激光Raman光谱仪测定了不同温度下固体和熔融状态的亚硝酸钠的拉曼光谱图,获得了有关固体和熔态NaNO2的结构信息,分析了NaNO2熔化过程中的结构变化。  相似文献   

16.
合成并表征了5-{2-[4-(2-氨基苯并咪唑)丁氧基]}苯基-10,15,20-三苯基卟啉及其铁(Ⅲ)、锰(Ⅲ)、钴(Ⅱ)和锌(Ⅱ)配合物,研究了它们的UV-Vis,IR,FAB,MS及^1H NMR谱,结果表明表明该类配合物中尾端基团配位于金属中心,且这类配合物在过氧化氢存在下,可催化烯烃的氧化。  相似文献   

17.
用红外吸收光谱、紫外吸收光谱、核磁共振(NMR)波谱(包含1H NMR、13C NMR、DEPT-135、COSY、HSQC和HMBC)、质谱、差示扫描量热分析、X-射线粉末衍射和元素分析等方法对卡巴他赛原料药精制品进行了结构确证,对其所有的1H和13C NMR信号进行了归属,同时讨论了质谱主要碎片离子可能的裂解方式和红外特征吸收峰所对应的官能团的振动形式,通过多种波谱技术结合确证了卡巴他赛的结构.  相似文献   

18.
Abstract

The stability of the doped state of conductive polythiophenes under air was investigated by the use of Infrared (IR) and UV-visible (UV) spectroscopies. Poly(3-methyl thiophene) doped with BF3-ethyl ether (BFEE). shows higher stability due to its stereoregularity-chain structure. While the doped polythiophene (PT) degrades easily under the moisture.  相似文献   

19.
亚碲酸铅玻璃微结构的Raman光谱研究   总被引:1,自引:0,他引:1  
测定了亚碲酸铅玻璃的常温及高温Raman光谱。实验表明随着PbO浓度增大,亚碲酸盐玻璃中的四配位与三配位结构单元之间存在转化关系,体系总体非桥氧数增加。当加入的PbO摩尔浓度增大至50%后,四配位结构单元密度相对较少,这时玻璃结构中主要以三配位结构单元形式存在。同时还测定了40PbO·60TeO2玻璃的升温Raman光谱,观察到四配位结构单元桥氧、四配位结构单元非桥氧以及三配位结构单元非桥氧对称伸缩振动的谱峰由于温度升高引起的结晶化过程导致向高频移动,谱峰变得尖锐,强度增大。熔点后,Raman光谱出现展宽效应,强度降低。在玻璃处于熔化状态下,四配位中的微结构单元会进一步向三配位转化,熔体内部微结构单元含量会相对平衡。  相似文献   

20.
Xiaolin Sun  Min Xin  Zhe Li 《光谱学快报》2013,46(8):1073-1082
The effect of solvent on the electronic spectra of some fasciolici-dal o–-hydroxylbenzenesulfonanilides is examined and discussed. It is revealed that in solution these compounds exist in both intramolecular hydrogen bond form and intermolecular hydrogen bond form occurring between solute and solvent molecule. In solutions containing large amount of apolar aprotic solvents such as dioxane, compounds studied are mainly intramolecular hydrogen bond form and exhibit a weak transition band which is presumably attributed to the transition of n-electrons of oxygen atom in the intramolecular hydrogen bonded six-membered ring of the compounds.  相似文献   

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