Co,Mn,Ni的联苯酸配合物的合成及光谱研究

合成了联苯酸 ,并以其和吡啶为配体 ,制备了第一过渡系金属离子Co(Ⅱ ) ,Mn(Ⅱ ) ,Ni(Ⅱ )的 3种配合物 ,并通过元素分析、IR及UV等手段对配合物进行了表征 ,推测了可能的组成和结构。     

氨基酸官能团的太赫兹振动模式研究

对比于氨基酸的红外分析法,太赫兹波的电子能量更低,可实现无损检测。氨基酸分子内原子振动、分子间氢键的作用、以及晶体中晶格的低频振动均处于太赫兹波段,使其在太赫兹波段具有吸收峰,且不同的氨基酸分子太赫兹吸收峰不同,故可用氨基酸在太赫兹波段的这种“指纹特性”实现氨基酸类物质的定性分析。量子化学分析方法可以应用量子力学的基本原理和方法,研究稳定和不稳定分子的结构、性能及其之间的关系,还可以针对分子与分子间的相互作用、相互碰撞及相互反应等问题进行研究。通过量子化学计算方法计算氨基酸分子的太赫兹吸收谱,可以为氨基酸分子的太赫兹吸收峰匹配分子振动模式,对氨基酸定性分析有一定参考性与指向性,并为实验获取的样品太赫兹时域光谱提供理论支撑,在实验获得太赫兹吸收谱的基础上进行量子化学计算,还能为实验结果进行验证。首先利用太赫兹时域光谱技术获取了谷氨酰胺、苏氨酸、组氨酸的太赫兹吸收谱,分别构建这三种氨基酸样品在实物中以两性离子形式存在的单分子构型,利用量子化学计算方法在完成结构优化后进行太赫兹吸收谱模拟计算。计算结果表明三种氨基酸单分子的太赫兹吸收谱计算结果与实验获取的太赫兹吸收谱差异较大,但在高频段吸收峰峰位基本吻合。通过GaussView分别查看了这三种氨基酸分子在太赫兹段内的吸收峰对应频率处的振转情况,发现在高频段内三种氨基酸分子官能团均只发生转动而未见振动,并且转动模式基本一致。通过对氨基酸官能团的太赫兹吸收谱进行量子化学计算,将官能团在高频段内吸收峰对应频率处的振转模式与三种氨基酸分子在该段内吸收峰对应频率处的振转模式做了对比。研究表明,在氨基酸单分子构型下由量子化学方法计算所得的太赫兹吸收谱中,高频段内计算得出的模拟吸收峰与实验获取的太赫兹吸收峰基本吻合;振转模式分析发现,谷氨酰胺、苏氨酸、组氨酸在太赫兹高频段内的氨基酸官能团振转模式相同,三种氨基酸分子在高频段内的吸收峰主要来源于氨基酸官能团。因此,结合量子化学计算与太赫兹吸收谱可以实现氨基酸类物质的定性分析。     

航天诱变番茄花粉的红外光谱研究

应用傅里叶红外光谱(FTIR),测试分析了4种番茄花粉样品的一维红外谱和二阶导数谱。结果表明,番茄花粉富含蛋白质、氨基酸和碳水化合物类成分;航天诱变选育番茄花粉的图谱与普通系统选育花粉的图谱基本类似,但在个别峰位处发生了变异。2种航天诱变选育花粉产生的共同变异是CH₃和C—O振动峰增强;不同的是大小番茄航天诱变选育花粉分别在酰胺Ⅰ带和酰胺Ⅱ带处的吸收增加。     

Effect of intravenous laser irradiation on the molecular structure of blood and blood components

We present the results of a spectral study of the effect of low-intensity laser radiation on the molecular structure of blood and blood components. Analysis of the Fourier transform IR absorption spectra of blood confirmed the changes we observed previously in the oxygen transport characteristics of blood with intravenous exposure to the emission from a He-Ne laser. We show that structural and conformational changes in the hemoglobin tetramer, initiated by laser-induced photoreactions between Hb and oxygen, lead to characteristic changes in the shape and intensity of the IR bands for NH stretching vibrations, and also the amide I and amide II absorption bands. In the IR spectra of irradiated blood samples, we note increased absorption in the bands for stretching vibrations of the phosphate groups (945–1280 cm⁻¹), which is evidence for an increase in the nucleic acid content (DNA, RNA). In the spectra of plasma and erythrocytes prepared from irradiated blood, there are no changes in this region of the IR spectrum. At the same time, in the IR spectra of samples of irradiated plasma, the intensity of the bands for stretching vibrations of the CH₂ groups increases substantially. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 1, pp. 106–112, January–February, 2006.     

稀土夹心双酞菁铥的LB膜及其光谱特性

采用表面压-面积(π～A)等温曲线和紫外-可见吸收光谱研究了稀土夹心双酞菁铥(TmPc2)分子在Langmuir膜及其Langmuir-Blodgett(LB)膜中分子的排列状态和光谱特性。发现TmPc2分子在纯膜中以edge-on方式面对面的排列,在与花生酸(AA)的混合膜中TmPc2分子以face-on方式平躺排列。纯的TmPc2分子在亚相表面可以形成稳定的Langmuir膜,但不易转移到固体基片上,加入花生酸混合后不仅可以在亚相表面形成稳定的Langmuir膜,而且可以较好地转移到固体基片上,制成多层LB膜。TmPc2氯仿溶液和LB膜的紫外-可见吸收光谱具有明显的Soret吸收带和Q吸收带,Soret吸收带有2个吸收峰,分别对应184—187*和178—186的轨道电子跃迁。而Q吸收带有4个吸收峰,分别对应于186—189*,190*和185—187*,188*的轨道电子跃迁。由于分子间的相互作用,TmPc2分子在LB膜中紫外-可见吸收谱的各个吸收峰与氯仿溶液中的吸收峰相比较都发生了红移。层内分子的相互作用比层间分子的相互作用强。     

脉冲升温纳秒时间分辨中红外光谱研究氨基酸重水溶液的分子间氢键

应用变温傅立叶变换红外光谱和脉冲升温纳秒时间分辨红外差谱研究了组氨酸和甘氨酸的重水溶液的羧基负离子的振动．结果表明不仅氨基酸分子之间形成氢键，而且氨基酸分子和溶剂分子之间也形成氢键．当温度升高时，羧基负离子在1600?1610 cm?1 附近的反对称伸缩振动发生蓝移，说明高温使氢键减弱．温度从10℃突然升高到20℃，组氨酸的时间分辨瞬态光谱出现两个漂白峰，一个在1604 cm?1，指认为形成氨基酸分子间氢键的羧基负离子的峰；另一个在1612 cm?1，指认为氨基酸分子和溶剂分子形成氢键的羧基负离子的峰．前     

pH诱导牛血清白蛋白芳香氨基酸残基微环境变化的光谱分析

用荧光光谱和紫外吸收光谱研究了ｐＨ＝２．３～１１．３范围内牛血清白蛋白（ＢＳＡ）芳香氨基酸残基微环境的变化,以此推断蛋白质构象的变化,并讨论蛋白质表面疏水性变化的趋热。与中性环境相比,ｐＨ为２．３时,色氨酸微环境的疏水性增强,蛋白质局部表面疏水降低;ｐＨ为１１．３时,部分Ｐｈｅ残基微环境的极性增强,表明碱诱导蛋白质分子变性使蛋白质分子充分伸展,将更多疏水性氨基酸残基暴露于溶剂中。     

Isotope shift in the spectrum of multiquantum absorption of nitromethane molecule in intense IR fields

The effect of isotope shift has been revealed in the spectra of absorption and dissociation of polyatomic molecules in an intense IR field, with no isotope shift present in the spectrum of linear absorption of a vibration being excited. The effect has been applied to separation of nitrogen isotopes in the nitromethane molecule. The effect considered increases considerably the number of molecules suitable for isotope separation by IR laser radiation.     

Calculation of infrared spectra for conformers of a dimeric fragment of the 2,6-hydroxyethylcellulose macromolecule in aqueous solution

Based on both a complete calculation of normal vibration frequencies and absolute IR absorption band intensities of a dimeric fragment of the 2,6-hydroxyethylcellulose macromolecule and a comparison of the results with the corresponding experimental data, a detailed interpretation of the IR spectrum (1200–960 cm^–1) of this polymer is given for the first time. Its conformational characteristics in aqueous solution at 20 and 70°C were determined by the molecular dynamics method. It is shown that the changes observed in IR spectra of hydroxyethylcellulose in aqueous solutions upon heating may be connected with conformational transitions of the ether side groups.     

Modelling of structure and interpretation of IR absorption spectra for crystals of substituted aryl propargyl ethers of phenols

IR absorption spectra of mesogenic crystals based on substituted aryl propargyl ethers of phenols (APEP) are calculated and analyzed using the LADY program. Force constants and interatomic potentials of atoms not covalently bonded adequately describe experimental IR spectra. The corresponding bands in the absorption spectra are interpreted. The influence of the substitution type on the force field of separate molecules in APEP crystals is clarified.     

溶剂对芳香胺红外吸收光谱的影响

对２１种芳香胺在不同溶剂中的红外光谱进行了测定,发现溶剂的极性对芳香胺氨基的红外光谱影响很大。在苯中氨基伸缩振动的频率红移的幅度明显大于在四氯化碳中的红移。由于溶剂和氨基之间形成氢键,在苯和四氯化碳中,氨基的两个吸收峰明显加宽。样品的浓度对吸收峰的频率,峰型及相对吸收强度都没有明显的影响。     

Luminescence and absorption spectra of polyatomic molecules subjected to conformational transitions

A general approach and results of specific calculations of conjugated vibronic absorption and fluorescence spectra of “soft” molecules subjected to conformational transitions are presented. The vibronic spectra of these molecules exhibit significant anomalies such as a large energy gap between the fluorescence and absorption spectra, a strong deviation from the mirror symmetry, etc., which cannot be explained within the framework of the theory of vibronic spectra based on single-well adiabatic potentials.     

氨基酸和羟肟酸混配的VO~(3+)配合物的IR、Raman和UV-Vis光谱研究

本文对四个钒酰配合物 [Vv O( L1- 3) ( bz) ]( H2 L1- 3分别为水杨醛缩合甘氨酸、缬氨酸、甲硫氨酸 ,Hbz为苯甲酰羟肟酸 )和 [Vv O( L4 ) ( bbz) ]( H2 L4 为水杨醛缩合丙氨酸 ,Hbbz为 N-苯基苯甲酰羟肟酸 )进行了 IR、Raman和 UV- Vis光谱研究。结果表明 ,在 IR和 Raman光谱中 ,它们有着相似的振动谱带 ,其νV=O特征振动频率出现在 962～ 976cm- 1之间 ;在 UV- Vis光谱中 ,含有 Hbz的配合物有两个配体场跃迁带 ,而含有 Hbbz的配合物只观测到一个配体场吸收带。     

Calculation and interpretation of IR and resonant raman spectra of 5-halosubstituted uracils

We have used valence optical theory to carry out calculation and analysis of in-plane vibrations and intensities of IR spectra for isolated 5-fluorouracil and 5-bromouracil molecules. We give a complete interpretation of the corresponding bands in the absorption spectra. We have carried out a quantum mechanical calculations of the relative intensities in the resonant Raman spectra of 5-fluorouracil and 5-chlorouracil. The calculated spectra for the molecular models obtained agree quantitatively with the experimental spectra, and reproduce the observed characteristic spectral differences in the series of molecules: uracil, 5-fluorouracil, 5-chlorouracil, and 5-bromouracil. The models obtained for the molecules can be used for calculation and analysis of the spectra of other halosubstituted nucleic acid bases. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 4, pp. 437–442, July–August, 2006.     

丙酮酸稀土配合物的红外光谱研究

研究了Ｙ,Ｌａ,Ｃｅ,Ｐｒ,Ｎｄ,Ｓｍ,Ｅｕ,Ｇｄ,Ｄｙ和Ｈｏ等１０种丙酮酸稀土配合物的ＦＴ－ＩＲ光谱;对４００～２０００ｃｍ＾－１的主要红外吸收谱峰进行了归属;２００～４－ｃｍ＾－１有３个随稀土原子序数递增峰位向高波数位移的谱带,可指认为ＲＥ－Ｏ伸缩振动吸收。红外光谱表明,丙酮酸以酸根形式采用螯合桥式三齿方式与稀土配位,某些谱峰有裂分或拓宽现象。配位键以离子键成分为主。     

Dynamic and Electro-Optical Nonequivalence of the NH Bonds of the Amino Group in Complexes of Dichloro-Substituted Anilines

The IR spectra of 1:1 and 1:2 complexes of dichloro-substituted anilines with various proton acceptors have been investigated and the parameters of the absorption bands of the stretching and deformation vibrations of their amino group have been determined. Vibrational and electro-optical problems have been solved for free and H-bonded molecules of the studied amines within the framework of the R-NH₂ model of a valence-free field. The geometric, dynamic, and electro-optical parameters of the amino group of dichloro-substituted anilines in complexes of different compositions have been determined. It is shown that the hydrogen bond in 1:1 complexes appears to be stronger than in 1:2 complexes.     

A computer study of the absorption spectra of the water-carbon monoxide disperse system

The IR absorption, emission, and reflectance spectra of (CO) _i (H₂O)₂₀, 1 ≤ i ≤ 10, clusters were calculated using the molecular dynamics model. After the adsorption of CO molecules by clusters, IR radiation absorption and reflection by the system composed of them weakened, whereas thermal radiation power increased. We tracked changes in spectral characteristics as the number of molecules in clusters increased. Growing water clusters decreased absorption and gradually increased IR emission power. The growth of a water cluster with the addition of CO molecules to it as a rule caused the opposite effect. On the whole, clusterization and the entrapment of CO molecules by clusters had an antigreenhouse effect.     

稀土-2, 3-二甲氧基苯甲酸-邻菲咯啉多元混配配合物的合成及表征

在水-乙醇的混合溶剂中,得到了NO-₃参与配位的稀土(RE3+)与2, 3-二甲氧基苯甲酸(2, 3-DMOBAH)及1,10-邻菲咯啉(Phen)的多元混配配合物。通过元素分析确定其组成为RE(2, 3-DMOBA)₂NO₃Phen(RE=La, Nd, Eu, Dy)。并利用红外吸收光谱,紫外吸收光谱,TG-DTA等对配合物进行了表征。     

Isotope shifts in spectra of molecular liquids

In the IR absorption spectra of low-temperature molecular liquids, we have observed anomalously large isotope shifts of frequencies of vibrational bands that are strong in the dipole absorption. The same effect has also been observed in their Raman spectra. At the same time, in the spectra of cryosolutions, the isotope shifts of the same bands coincide with a high accuracy (±(0.1–0.5) cm^–1) with the shifts that are observed in the spectra of the gas phase. The difference between the spectra of examined low-temperature systems is caused by the occurrence of resonant dipole–dipole interactions between spectrally active identical molecules. The calculation of the band contour in the spectrum of liquid freon that we have performed in this work taking into account the resonant interaction between states of simultaneous transitions in isotopically substituted molecules can explain this effect.     

Ultrasonic spectroscopy in bovine serum albumin solutions

Ultrasonic absorption and velocity spectra in bovine serum albumin (BSA) aqueous solutions have been measured at 20 degrees C over the broad frequency range 0.1-1600 MHz in the pH range 1.5-13.2. Five different techniques were used: the plano-concave resonator, plano-plano resonator, pulse-echo overlap, Bragg reflection, and high-resolution Bragg reflection methods. The absorption spectrum at neutral pH was well fitted to the relaxation curve assuming a distribution of relaxation frequency with a high-frequency cutoff and long low-frequency tail. The relaxation behavior was interpreted in terms of various degrees of hydration of BSA molecules. At acid pH's, excess absorption over that at pH 7 was explained by double relaxation. The pH dependences of the relaxation frequency and maximum absorption per wavelength showed that the relaxation at about 200 kHz was related to the expansion of molecules and that at 2 MHz resulted from the proton transfer reaction of carboxyl group. At alkaline pH's, the excess absorption was explained by triple relaxation. The relaxation at about 200 kHz was associated with a helix-coil transition, and the two relaxations at 2 and 15 MHz were attributed to the proton transfer reactions of phenolic and amino groups, respectively. The rate constants and volume changes associated with these processes were estimated.