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1.
本文对高山红景天提取物中的一种新化合物进行了红外和拉曼光谱的测定,并对主要谱带进行了归属和讨论。  相似文献   

2.
振动光谱(红外光谱和拉曼光谱)技术与化学计量学相结合的方法对微生物进行分类、鉴定和无损检测,该方法快速简便、准确度高、仅需微量样品和少量化学试剂、对样品本身没有损害。介绍了振动光谱技术在微生物鉴定检测中的工作原理、关键技术和应用,并对该方法存在的问题和研究前景进行了分析和展望。  相似文献   

3.
稀土(镧、镨、钕)氯化物与苯并咪唑配合物的光谱特性   总被引:1,自引:1,他引:0  
用傅里叶变换红外光谱、喇曼光谱、紫外光谱、荧光光谱和X粉晶衍射等多种光谱手段对氯化稀土(La、Pr、Nd)与苯并咪唑(Bim)配合物进行了分析,对配合物的光谱特性和结构进行了讨论和表征.  相似文献   

4.
锗等离子体远紫外光谱研究   总被引:2,自引:0,他引:2       下载免费PDF全文
测量了线聚焦激光加热锗等离子体发射的远紫外光谱,对GeXX-GeXXVI谱线进行了辨认和分类。给出了谱线波长和相对强度;计算了辐射跃迁概率和吸收振子强度;并;与其他实验室有关结果进行了比较。 关键词:  相似文献   

5.
作为一种快速、无损的分析技术,近红外光谱分析在许多领域中被广泛应用,其中液体样品是其应用最为广泛的分析对象之一.由于水等常用溶剂在近红外波段的温度敏感性极高,因而不能忽视温度对溶液的近红外光谱测量带来的影响.文章以朗伯-比尔定律为基础,在理论上推导出了温度变化对溶液透射光谱的影响,并提出利用纯溶剂在不同温度下的吸光度变化量作为温度校正量,对样品光谱进行修正.文章还在不同温度下,对葡萄糖水溶液和白蛋白水溶液进行了光谱测量,建立了30℃下的校正模型,并以纯水的吸光度变化量为温度校正量,将不同温度下的预测样品光谱修正至对应于30℃的光谱.实验结果表明,对光谱进行温度修正后,有效消除了温度对光谱的影响,葡萄糖和白蛋白的浓度预测误差得到了明显的降低.  相似文献   

6.
本文对鬼臼毒素及其衍生物的吸收光谱进行了详细研究,分别运用了紫外法,荧光法,脉冲辐解法,激光光解法。对一些瞬态中间体进行理论和实验的推测,从而对鬼臼素及其衍生物的抗肿瘤活性和毒性的研究提供了有力证据,为进一步合成具有高抗肿瘤活性,低毒性的新物质指明了方向和提供了理论基础。  相似文献   

7.
本文对新型有机光学非线性晶体LAP的晶格振动进行了群论分析.并记录了各种几何配置下LAP单晶及其氘化物DLAP单晶在50~3700cm~(-1)范围的偏振喇曼光谱及偏振红外反射光谱.对谱图进行了识别.对LAP和DLAP单晶中NH_3~+,PO_4~(3-),COO~-基团的内振动进行了比较.实验结果表明DLAP单晶和LAP单晶具有相同的对称性.氘化使晶体的通光范围向红外方向扩展.  相似文献   

8.
通过重氮化偶联反应制备了一种既含偶氮基团又含咔唑基团的光折变材料,并通过红外、紫外和拉曼光谱对其进行了结构鉴定和分析.  相似文献   

9.
ZnO纳米棒的拉曼和发光光谱研究(英文)   总被引:1,自引:0,他引:1  
本文对采用湿化学方法合成的ZnO纳米棒样品的拉曼光谱和发光光谱进行了研究。由扫描电镜结果可知,合成的ZnO纳米棒具有很好的尺寸发布均匀性,直径在30 nm左右,长度大于1微米。采用显微拉曼光谱技术,得到了632.8 nm波长激发的拉曼光谱,并和体相样品的拉曼光谱进行了对比分析;由325 nm激光波长激发得到的荧光光谱可知样品具有很好的紫外发光性质。  相似文献   

10.
基于空间特征的光谱分类算法研究   总被引:1,自引:0,他引:1  
随着成像光谱仪器的广泛应用,利用数据立方体进行物质分类与识别成为一项重要的研究内容,分类算法对最终的目标识别准确度与精度具有很大的决定作用。目前常见的分类算法主要利用了光谱维信息,从光谱匹配的角度进行物质分类。由于仪器探测的物质反射光谱不仅反映了物质种类,还与物质表面的几何结构,表面粗糙度等有关,因此仅仅利用物质的反射光谱进行物质分类识别具有一定的误差。该文在利用可见光反射光谱进行分类的基础上,结合图像空间特征,对分类过程进行控制,达到提高分类准确度的目的。利用该分类算法进行真假叶片识别,结果表明其具有较好的空间连续性,很大程度上克服了"麻点"效应,验证了算法的有效性。  相似文献   

11.
银合欢叶成分槲皮素-3-O-鼠李糖甙的FT-IR和FT-Raman光谱   总被引:7,自引:1,他引:6  
本文对银合欢叶中的成分槲皮素 - 3- O-鼠李糖甙进行了红外和拉曼光谱的测定 ,并对测定结果进行了详细的分析和讨论  相似文献   

12.
Fourier transform (FT)‐Raman and Fourier transform infrared (FT‐IR) spectra of 3‐{[(4‐fluorophenyl)methylene]amino}‐2‐phenylquinazolin‐4(3H)‐one were recorded and analyzed. The vibrational wavenumbers of the title compound were computed using the B3LYP/6‐31G* basis and compared with the experimental data. The prepared compound was identified by NMR and mass spectra. The simultaneous IR and Raman activation of the CO stretching mode shows a charge transfer interaction through a π‐conjugated path. The first hyperpolarizability and infrared intensities are reported. The assignments of the normal modes are done by potential energy distribution (PED) calculations. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

13.
Fourier transform infrared (FT‐IR) and Fourier transform (FT) Raman spectra of 3‐{[(2‐hydroxyphenyl)methylene]amino}‐2‐phenylquinazolin‐4(3H)‐one were recorded and analyzed. The vibrational wavenumbers of the title compound were computed using HF/6‐31G* and 6‐311G* basis sets and compared with experimental data. The assignments of the normal modes are done by potential energy distribution (PED)calculations. The prepared compound was identified by nuclear magnetic resonance (NMR) and mass spectra. Optimized geometrical parameters of the title compound are in agreement with reported structures. Shortening of CN bond lengths reveal the effect of resonance. The simultaneous IR and Raman activations of the CO stretching mode shows a charge transfer interaction through a π‐conjugated path. The first hyperpolarizability, infrared intensities and Raman activities are reported. The phenyl C C stretching modes are equally active as strong bands in both IR and Raman spectra, which are responsible for hyperpolarizability enhancement leading to nonlinear optical activity. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

14.
The influence of lithium, sodium, potassium, rubidium, and cesium on the electronic system of the 4‐nitrobenzoic acid molecule was studied. The vibrational (FT‐IR, FT‐Raman) and NMR (1H and 13C) spectra for 4‐nitrobenzoic acid salts of alkali metals were recorded. The assignment of vibrational spectra was done. Characteristic shifts of band wavenumbers and change in band intensities along the metal series were observed. Good correlation between the wavenumbers of the vibrational bands in the IR and Raman spectra for 4‐nitrobenzoates and ionic potential, electronegativity, atomic mass, and affinity of metals were found. The chemical shifts of protons and carbons (1H, 13C NMR) in the series of studied alkali metal 4‐nitrobenzoates were observed too. Optimized geometrical structures of studied compounds were calculated by HF, B3PW91, B3LYP methods using 6‐311++G** basis set. The theoretical IR, Raman, and NMR spectra were obtained. The theoretical vibrational spectra were interpreted by means of potential energy distributions (PEDs) using VEDA 3 program. The calculated parameters were compared to experimental characteristic of studied compounds. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

15.
作者对金属硫蛋白 ( MT)进行了分离 ,得到了单一的 MT- 和 MT- 组份 ,并用傅立叶变换拉曼和傅立叶变换红外光谱测定了它们的二级结构。对两者的谱图加以分析 ,发现MT- 和 MT- 的振动光谱在酰胺 带和酰胺 带范围内有较明显的区别 ,而它们在金属簇结构范围内的振动无明显差异  相似文献   

16.
As an important chemosensing material involving hexafluoroisopropanol (HFIP) for detecting nerve agents, para‐HFIP aniline (p‐HFIPA) has been firstly synthesized through a new reaction approach and then characterized by nuclear magnetic resonance and mass spectrometry experiments. Fourier transform infrared absorption spectroscopy (FT‐IR) and FT‐Raman spectra of p‐HFIPA have been obtained in the regions of 4000–500 and 4000–200 cm−1, respectively. Detailed identifications of its fundamental vibrational bands have been given for the first time. Moreover, p‐HFIPA has been optimized and vibrational wavenumber analysis can be subsequently performed via density functional theory (DFT) approach in order to assist these identifications in the experimental FT‐IR and FT‐Raman spectra. The present experimental FT‐IR and FT‐Raman spectra of p‐HFIPA are in good agreement with theoretical FT‐IR and FT‐Raman spectra. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

17.
FT‐IR and FT‐Raman spectra of p‐bromonitrobenzene (p‐BNB) have been recorded in the region 4000–400 cm−1 and 4000–50 cm−1, respectively. The molecular structure, geometry optimization, vibrational wavenumbers have been investigated. The spectra were interpreted with the aid of normal coordinate analysis based on the density functional theory (DFT) using the standard B3LYP/6‐31G method and basis set combination and was scaled using multiple scale factors yielding good agreement between observed and calculated wavenumbers. The results of the calculations are applied to simulate infrared and Raman spectra of the title compound which showed reasonable agreement with the observed spectra. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

18.
Dimethyl 1,3‐dithiole‐2‐thione‐4,5‐dicarboxylate (DDTD) was synthesized and characterized using NMR, Fourier transform (FT)‐Raman, Fourier transform‐infrared (FT‐IR) and UV spectroscopies. Resonance Raman spectra (RRs) were obtained with 341.5, 354.7 and 368.9 nm excitation wavelengths and density functional calculations were carried out to elucidate the π (S C S) →π* (S C S) electronic transitions and the RRs of DDTD in cyclohexane solution. The RRs indicate that the Franck–Condon region photo dynamics have a multidimensional character with motion predominantly along the CS stretch and the C S symmetric stretch modes in the five‐member heterocycle. A preliminary resonance Raman intensity analysis was carried out and the results for DDTD were compared with previously reported results for 1,3‐dithiole‐2‐thione (DTT). Differences and similarities of the spectra in terms of molecular symmetry and electron density are also discussed. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

19.
The nonlinear optical (NLO) compound of interest benzophenone thiosemicarbazone (BTSC) was grown and the molecular structure generated with the aid of density functional theory (DFT). FT‐Raman and IR spectra were recorded and analyzed. The harmonic wavenumbers and IR and Raman intensities were computed with the B3LYP method. The observed vibrational wavenumbers were compared with the calculated results. The assignments of the experimental spectra were made with the help of normal coordinate analysis (NCA) following the scaled quantum mechanical force field (SQMFF) methodology. The electronic structure of the most important molecular fragments is described in terms of natural bond orbital (NBO) analysis. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

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