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1.
碳酸脱水酶去卷曲构象的FT┐Raman观测左晨周群童宇峰郁鉴源(清华大学化学系北京100084)FT┐RamanSpectroscopicStudyontheConformationofUnfoldedCarbonicAnhydraseZuoChen...  相似文献   

2.
固态六羰基钼的FT┐拉曼光谱研究李淑玲(地矿部岩矿技术研究所北京100037)任玲(北京理工大学化学与材料学院北京100081)FT┐RamanSpectraofSolidMo(CO)6LiShuling(InstituteofRockandMine...  相似文献   

3.
付立叶变换拉曼光谱研究液晶分子结构   总被引:1,自引:0,他引:1  
付立叶变换拉曼光谱研究液晶分子结构姜世梅吴英徐蔚青李伯符(吉林大学国家教委超分子结构与谱学开放实验室长春130023)田颜清赵英英汤心颐(吉林大学化学系长春130023)FT┐RamanSpectroscopicStudiesontheMolecul...  相似文献   

4.
显微拉曼中激光的注入和剔除DaSilvaEdouard,OswaltJoelLaserLightInjectionAndRejectionInMicro┐RamanDasilvaEdouard,OswaltJoel*(InstrumentsS.A.D...  相似文献   

5.
配合物(PP)2Cu和(PP)3Fe的FT┐Raman和FT┐IR光谱研究(PP=2┐(2┐氧基┐苯基)吡啶)王悦姜世梅李艳芹(吉林大学超分子结构与谱学开放实验室长春130021)FT┐RamanandFT┐IRSpectraofCuandFeCom...  相似文献   

6.
竹红菌甲乙素的FT-Raman光谱张自禄胡鑫尧卢为琴周群郁鉴源胡义镇*(清华大学化学系北京100084)(*中科院感光所北京100101)FT-RamanSperctraofHypocrelinAandHypocrelinBZhangZilu,HuX...  相似文献   

7.
铁掺杂的纳米SnO2的拉曼散射吴若(江西师范大学物理系南昌330027)左健(中国技术大学结构分析开放实验室合肥230026)RamanScateringofFe┐dopedNanoscaleSnO2WuRuo(DepartmentofPhysics...  相似文献   

8.
水杨酸分子NIR-FT-SERS与VIS-SERS的比较研究方炎,汪媛,胡凤霞(首都师范大学实验中心,首都师范大学综合所北京100037)TheComparisonofVIS-SERStoNIR-FT-SERSofMoleculesAdsorbedo...  相似文献   

9.
本文通过对近红外激发傅里叶变换拉曼光谱(NIR-FT-Raman)与表面增强拉曼散射(Surface Enhanced Raman Scattering,SERS)技术的联用,没得胆红素及其络合物Na2BR,CaBR与CuBR在银溶胶中的SERS光谱。结果表明,这一类与胆结石密切相关的生物分子络合物具有不同的配位方式,且在银胶表面采取不同的吸附取向,并从配位化学角度初步解释了黑色结石的黑色成因。  相似文献   

10.
Nd:YAG1064nm激发的葡萄糖氧化酶在银胶体系中的FT-Raman谱胡凤霞,张崇起,方炎(首都师范大学综合所物理系实验中心北京100037)FourierTransformSurface-EnhancedRamanSpectroscopyofG...  相似文献   

11.
The interactions of the amino acid side-chains arginine (ARG), aspartic acid (ASP), asparagine (ASN), lysine (LYS) and serine (SER) with nucleic acid base pairs have been investigated using theoretical methods. The interaction energy of the short intermolecular N–H?···?N, N–H?···?O, O–H?···?O, O–H?···?N, C–H?···?O and C–H?···?N hydrogen bonds present in both isolated base pairs and complexes and its role in providing stability to the complexes have been explored. The homonuclear interactions are found to be stronger than the heteronuclear interactions. An improper hydrogen bond has been observed for some of the N–H?···?O and N–H?···?N hydrogen-bond interactions with the contraction of the N–H bond varying from 0.001 to 0.0260?Å and the corresponding blue shift of the stretching frequency by 4–291?cm?1. Localized molecular orbital energy decomposition analysis (LMOEDA) reveals that the major contributions to the energetics are from the long-range polarization (PL) interaction, and the short-range attractive (ES, EX) and repulsive (REP) interactions. The Bader's atoms in molecules (AIM) theory shows good correlation for the electron density and its Laplacian at the bond critical points (BCP) with the N–H?···?N and N–H?···?O hydrogen-bond lengths in the complexes, and gives a proper explanation for the stability of the structure. The charge-transfer from the proton acceptor to the antibonding orbital of the X–H bond in the complexes was studied using natural bond orbital (NBO) analysis.  相似文献   

12.
以Bi(NO3)3.5H2O,Nd(NO3)3.6H2O和Ti(OC4H9)4为原料,加入聚乙烯醇(PVA-124),采用水热法在200℃经48 h合成了铋层状钙钛矿结构掺钕钛酸铋(Bi3.15Nd0.85Ti3O12,BNdT)纳米棒,纳米棒直径约10~200 nm,长度达十几微米。利用Raman散射研究了掺钕对钛酸铋晶格结构的影响。掺钕钛酸铋和钛酸铋的Raman光谱表明,Nd取代了类钙钛矿层中A位的Bi,掺Nd改善了BTO的对称性和减小了TiO6八面体的畸变。利用UV-vis光谱研究了BNdT纳米棒的光吸收特性,BNdT纳米棒存在A(400 nm),B(275 nm),C(210 nm),D(196 nm)四个吸收带,分别对应于电子从Bi3+的基态1S0到激发态3P1,3P2,1P1的跃迁和电子从阴离子团TiO6八面体到带正电的Bi3+离子的跃迁。BNdT的带隙为4.3 eV,大的带隙归因于纳米结构的量子尺寸效应。  相似文献   

13.
用G3B3//B3LYP/6-311G(d,p)方法计算了戊二烯基与氧分子反应的势能面.计算结果显示,反应的第一步为戊二烯基与氧分子结合形成两种过氧化加成物,过氧基分别连结在末端C1位置和中间C3位置.在反应的第二步,两种过氧化加成物分别发生一系列氢转移异构化反应和成环异构化反应.最后,这些氢转移异构体和环化异构体分别经过单分子分解通道,生成不饱和醛酮和羟基.共计算了20个稳定态和14个过渡态的结构和能量,通过比较各反应通道的能垒和反应热,提出以C2H3O和C3H4O为最终产物的通道可能是整个反应的主要通道.此外,计算结果还表明一些过C5H7O2自由基可能作为反应体系的长寿命中间体而存在,这与Zils等人的实验观测结果一致.  相似文献   

14.
在软X射线掠射光学系统筒状反射镜的加工过程中,根据对反射镜内表面镍磷合金镀层的质量要求,采用镍盐还原法对筒状微晶玻璃反射镜的内表面进行了活化,并对在含有30g/LNiSO4.6H2O、30g/LNaH2PO2.H2O、25g/LNa(CH3COO).4H2O、18g/LC6H8O7、10mg/L添加剂的镀液中沉积镍磷合金镀层的工艺方法进行了探索。对得到的镍磷合金镀层的结合力、抗腐蚀能力等进行了测试。结果表明,采用此法镀制的镍磷合金镀层结合力达到4B级,耐蚀性好,能够满足光学精密抛光的要求。  相似文献   

15.
Molecular dynamics simulations have been carried out for glycerol–water–sodium chloride ternary solution due to its important role in cryopreservation engineering. The radial distribution functions for atom pairs potentially related to C–H ··· O and O–H ··· O hydrogen bonds were calculated. The radial distribution functions for the H (connected to C)–O atom pair do not exhibit peaks between 2 and 3 Å, whereas the radial distribution functions for the C–O atom pair exhibit distinct peaks between 3 and 4 Å. The reason for this is because most C–H ··· O geometries are bent and deviate from linearity. The ratios of acceptor to donor numbers for water and glycerol molecules decrease as the solute concentration increases. A characteristic concentration has been found that divides solutions with different mechanisms. Below the characteristic concentration, the melting temperature is linearly related to the ratio of acceptor to donor number for water molecules, whereas above the characteristic concentration, the melting temperature is linearly related to the ratio of acceptor to donor number for glycerol molecules. Further studies indicate that the relations are independent of hydrogen bonding criteria and temperature.  相似文献   

16.
The intramolecular С=O→Si coordination in H‐complexes of (acetoxymethyl)trifluorosilane and (benzoyloxymethyl)trifluorosilane with proton donors HCl, PhOH, MeOH, and CHCl3 was investigated by density functional theory and second‐order Møller‐Plesset perturbation theory (MP2) methods. Interrelation and mutual influence of the intramolecular coordination bond С=O→Si and intermolecular hydrogen bonds C=O···H and Si–F···H in H‐complexes was established using the AIM and NBO analyses. The С=O→Si coordination is weakened by the C=O···H hydrogen bonding but enhanced by the Si–Fax···H hydrogen bonding. The structure of H‐complexes of (acetoxymethyl)trifluorosilane with proton donors in solution was determined by comparing the ν(C=O) and ν(Si–F) frequencies calculated using the conductor‐like polarizable continuum model and their experimental Fourier transform infrared values. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

17.
The structure of an H(2)O monolayer bound to atomically smooth hydroxylated amorphous silica is probed under ambient conditions by near-infrared evanescent-wave cavity ring-down absorption spectroscopy. Employing a miniature monolithic optical resonator, we find sharp (approximately 10 cm(-1)) and polarized (>10:1) vibration-combination bands for surface OH and adsorbed H(2)O, which reveal ordered species in distinct local environments. Indicating first-monolayer uniqueness, the absorption bands for adsorbed H(2)O show intensity saturation and line narrowing with completion of one monolayer. Formation of the ordered H(2)O monolayer likely arises from H bonding to a quasicrystalline surface OH network.  相似文献   

18.
二正丁基锡三齿酰腙Schiff碱配合物的合成和红外光谱研究   总被引:7,自引:3,他引:4  
合成了 4种三齿酰腙Schiff碱配体H2 L [H2 L1 :C6 H5C(O)NHN =CHC6 H4OH 2 ,H2 L2 :C6 H5C(O)NHN =CHC6 H3(OH) 2 2 ,4,H2 L3:NC5H4C(O)NHN =CHC6 H4OH 2 ,H2 L4:NC5H4C(O)NHN =CHC6 H3(OH) 2 2 ,4]和它们的二正丁基锡新型配合物 (n Bu) 2 SnL ,通过元素分析确定了这些配合物的组成 ,并对配合物在 4 0 0 0~ 40 0cm- 1范围内的主要红外光谱吸收峰进行了归属和讨论 ,推测出配合物可能的分子结构。  相似文献   

19.
张英兰  金昌根 《发光学报》1989,10(3):219-224
本文首次报导了采用碱式碳酸盐和氟化铵一步合成MeF2:Mn2+长余辉材料新方法。研究了各种条件和Mn2+浓度对荧光粉的影响,所得到的MgF2:Mn2+发射为橙红色,主峰在590nm,色度值为x=0.559,y=0.438,余辉大约200ms。荧光粉呈现均匀圆球状的颗粒,属于四方晶系。  相似文献   

20.
In this work, we present the optimized ground state geometrical structures, electronic excitation energies and corresponding oscillation strengths of the low‐lying electronically excited states for the isolated Tce‐CH3COCOOH and Tce‐CH3C(OH)2COOH as well as their corresponding hydrogen‐bonded dimers Tce‐CH3COCOOH‐H2O and Tce‐CH3C(OH)2COOH‐H2O through time‐dependent density functional theory method. It is found that the intermolecular hydrogen bonds C=O···H‐O are strengthened in the electronically excited states of the hydrogen‐bonded dimers Tce‐CH3COCOOH‐H2O and Tce‐CH3C(OH)2COOH‐H2O, in that the excitation energies of the related excited states for the hydrogen‐bonded dimers are decreased compared with those of the corresponding monomers. The calculated results are consistent with the rules that are first demonstrated by Zhao on the excited‐state hydrogen bonding dynamics. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

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