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1.
采用一维红外光谱、二阶导数谱和二维相关红外光谱对溪黄草原药材及其不同溶剂提取物进行了红外光谱研究。结果表明:溪黄草原药材中含有酯类、芳香类和糖苷类等物质,溪黄草水提物中主要为糖类物质,乙醇提取物中主要为黄酮类物质,石油醚提取物中主要为酯类物质。红外光谱能够快速、简便地提供中药及其提取物中主要化学成分的宏观信息,从而为后续的化学成分分析和中药提取分离方法的改进和优化提供有效参考。  相似文献   

2.
红外光谱法对肉苁蓉径向不同部位的分析与评价   总被引:9,自引:0,他引:9  
采用傅里叶变换红外光谱、二阶导数谱和二维相关红外光谱技术对肉苁蓉由表及里3个部位的药材粉末及其水提物和醇提物进行了分析与评价研究.结果表明,肉苁蓉不同部位的一维光谱非常相似,三者相似系数分别为0.9605,0.944和0.976;二阶导数谱中峰位和峰强的差异明显.1430~1700 cm-1范围内的二维相关谱中皮部自动峰有3个,而中部及髓部均为4个,更直观的反映出三者的差异.不同部位水提物和醇提物的分析结果进一步明确了肉苁蓉皮部芳香类、环烯醚萜类及糖苷类物质与中部和髓部存在明显不同,而髓部的水溶性多糖、半乳糖醇和苯乙醇苷类物质均高于其它部位.可见红外光谱法结合二维相关红外光谱技术为同种药材不同部位的细微差异分析和评价提供了一种快速、全面和客观的方法和手段.  相似文献   

3.
变温傅里叶红外光谱技术研究硬脂酸C-H伸缩振动   总被引:1,自引:0,他引:1  
采用傅里叶红外光谱技术研究了温度对于硬脂酸C-H伸缩振动、分子脂肪链构象改变和分子间作用力的影响。运用变温红外技术在293~393K范围内,分别测定了硬脂酸C-H的一维红外光谱、二阶导数红外光谱、四阶导数红外光谱和去卷积红外光谱。结果表明:1在293~333K范围内,一维红外光谱中2 965,2 870cm-1附近的弱吸收谱带分别归属于甲基的不对称伸缩振动模式νas(-CH3)和对称伸缩振动模式νs(-CH3),相应的导数光谱及去卷积红外光谱能提高一维红外谱的分辨率;2在293~333K范围内,硬脂酸脂肪链处于全反式构象,在348~353K范围内,硬脂酸分子脂肪链构象由全反式构象向无序构象转变;3随着测量温度的升高,硬脂酸分子间的作用力不断降低。  相似文献   

4.
采用红外光谱、二阶导数红外光谱和二维相关红外光谱,对四种不同产地的黄芪原药材进行了鉴别研究。结果表明:不同产地黄芪的红外光谱和二阶导数红外谱具有一定的相似度,与淀粉的红外谱图比对,4个不同产地的黄芪均含有淀粉,其中陕西绥德产黄芪的淀粉含量比其它3个产地黄芪的都要高。山西浑源和山西天镇产黄芪谱图的1 510、1 425cm-1木质素特征峰比内蒙古固阳和陕西绥德产黄芪的更为明显,说明前二者产黄芪中木质素含量高于后二者产黄芪。在二维相关红外谱图上,根据4个产地黄芪的相对峰强度的差异,可进行产地的鉴别。研究结果表明对于不同产地黄芪的鉴别,红外三级鉴定法是一种快速有效的新方法。  相似文献   

5.
利用流变学方法, 采用核磁共振和红外光谱技术开展了聚乙烯吡咯烷酮(PVP)和LiCl相互作用研究, PVP/LiCl/DMF浓溶液的表观粘度随着LiCl含量的增加而提高, 溶液的粘流活化能也相应增加. 13C NMR结果表明, 溶液中Li+与PVP的羰基之间存在相互作用, 这种相互作用改变了PVP分子的聚集状态. 红外光谱结果证实了PVP/LiCl复合物中Li+与PVP的羰基存在相互作用.  相似文献   

6.
大黄的傅里叶变换红外光谱法快速鉴别   总被引:8,自引:0,他引:8  
利用傅里叶变换红外(FTIR)光谱法对不同的大黄药材进行了分析?结果表明:大黄样品在4000~1800cm^-1区域有相似的红外光谱特征,而在1800~400cm^-1区域不同组系、不同品种的样品又存在很大差异。因此红外光谱法可以快速、简便、直观地对中药材进行质量鉴别。  相似文献   

7.
大豆蛋白的中红外和近红外光谱研究*   总被引:2,自引:0,他引:2  
江艳  武培怡 《化学进展》2009,21(4):705-714
大豆蛋白在各领域的应用已得到广泛的关注,因此大豆蛋白及其改性材料在结构性能方面的研究显得越来越重要。中红外光谱(mid-infrared spectroscopy,MIR)和近红外光谱(near-infrared spectroscopy,NIR)正是对蛋白质进行定性定量分析的有力手段。中红外光谱可以有效地分析大豆蛋白在溶液和薄膜中的二级结构以及大豆衍生材料内蛋白质的结构变化情况。近红外光谱则在蛋白质定量分析方面有着独特的优势。本文介绍了运用这两种光谱技术进行研究的一些工作,这些实例表明了中红外和近红外光谱在大豆蛋白研究领域的重要应用价值。  相似文献   

8.
张力群  李浩然 《物理化学学报》2010,26(11):2877-2889
热力学实验、理论计算以及计算机模拟是离子液体微观结构与相互作用研究中常用的三种手段,但是目前采用这些手段对离子液体结构的认识尚处于初步探索阶段,还没有完全找到离子液体性质随结构变化的规律,尚未完全能够对离子液体进行"设计",这也使得对离子液体的进一步开发和应用受到极大的限制.近年来,谱学方法成为研究溶液结构的重要手段.其中,红外光谱(IR)和拉曼光谱(Raman)等谱学手段在离子液体的结构与相互作用研究中发挥着越来越重要的作用.本文着重概述了红外光谱和拉曼光谱在纯离子液体及离子液体混合溶液结构与相互作用方面的研究进展、挑战以及发展方向.  相似文献   

9.
采用物化性质稳定的单晶硅作为基质,以直流磁控溅射方式轻蒸镀不同厚度的镍、铬混合膜层,实现了中红外波段(500~4000 cm^–1)不同透射比标准物质的研制。研制的中红外光谱透射比标准物质其透射比标称值分别为10%和50%,扩展不确定度优于0.008(k=2)。该标准物质具有量值稳定、光谱平坦等特点,可用于各类傅里叶变换红外光谱设备的透射比校准。  相似文献   

10.
配合物EuxM1-x(TTA)3(H2O)2(M=La,Gd)光致发光特性   总被引:13,自引:0,他引:13  
合成了一系列组成为EuxM1-x(TTA)3(H2O)2(M=La,Gd)的固体配合物,利用红外光谱和荧光光谱研究了配合物结构和发光性质随Eu3+浓度的变化规律.红外光谱的结果表明,配合物的成份为Eu(TTA)3(H2O)2和M(TTA)3(H2O)2,没有新化合物生成.而荧光光谱的结果显示配合物的发光强度与Eu3+浓度不成线性关系,其中不发光的M(TTA)3组分对发光有增益作用.对其可能的发光机制进行了探讨.  相似文献   

11.
In this study,a convenient method using multi-step infrared spectroscopy,including Fourier transform infrared spectroscopy(FT-IR),second derivative infrared spectroscopy(SD-IR) and two-dimensional correlation infrared spectroscopy(2DCOS-IR),was employed to analyze and discriminate ten marine sponges from two classes collected from the Xisha Islands in the South China Sea.Each sponge had an exclusive macroscopic fingerprint.From the IR spectra,it was noted that the main ingredient of calcareous sponges was calcium carbonate,but that of demosponges was proteins.For sponges from the same genus or having highly similar chemical profile(IR spectral profile),SD-IR and 2DCOS-IR were applied to successfully reveal the tiny differences.It was demonstrated that the multi-step infrared spectroscopy was a feasible and objective approach for marine sponge identification.  相似文献   

12.
通过置换反应在金属铝表面制备了表面没有任何保护剂且具有红外增强作用的钴岛膜,用SEM、XRD和表面增强红外光谱对其形貌和性质进行表征。 结果表明,铝片上沉积出的钴呈岛状结构,钴岛膜由二次钴粒子和一次钴粒子通过密堆积的方式构成;首次发现具有这种特殊结构的钴对吸附于其表面的有机分子的红外吸收光谱有较大的增强作用,用此钴岛膜对1 mmol/L的对巯基苯甲酸的红外光谱研究时得到很好的红外增强信号,使得表面增强红外光谱可以用于痕量分析、检测。  相似文献   

13.
6种燕窝的傅里叶变换红外光谱法原性状快速鉴别   总被引:32,自引:0,他引:32  
首次利用微钻石ATR探头傅里叶变换红外光谱法(FTIR)无损快速鉴别了6种燕窝。结果表明:印尼燕、越南燕、马来西亚燕、泰国血燕、菲律宾草燕和香港市售燕窝均有自己的红外特征谱,据谱图吸收峰的波数位置和相对峰强度的差异可达到燕窝类同和伪品和鉴别。该方法快速、简便、可靠。  相似文献   

14.
草乌中二萜类生物碱的电喷雾串联质谱研究   总被引:10,自引:0,他引:10  
利用电喷雾质谱技术对传统中药草乌中的二萜类生物碱进行直接分析鉴定.通过实验数据并对比文献发现,草乌中含有单酯型、双酯型、三酯型和脂类等共4种类型生物碱,其中三酯型和脂类生物碱在草乌中为首次发现.由于这些生物碱的结构相似,在电喷雾串联质谱中碎裂方式相同,因此根据电喷雾串联质谱结果确定了这些生物碱的结构.  相似文献   

15.
Two-dimensional infrared (2D IR) correlation spectroscopy was applied to study the structural changes occurring in the decomposition of PHEA-co-MMA/SiO2. Complicated absorption spectral changes were observed in the heating process. 2D IR analysis indicates that during heating, covalent bonds, (Si-O-C), between the polymer and the inorganic moiety were formed, which was the main factor in the improvement in thermal properties of the hybrids such as the decomposition temperatures (Td). The thermal stability of the hybrids was also studied by solid-state 29Si MAS NMR spectroscopy and TGA tests. Their results complemented each other well.  相似文献   

16.
36种灵芝产品傅里叶变换红外光谱快速鉴别研究   总被引:23,自引:0,他引:23  
利用傅里叶变换红外光谱法(FTIR)无损快速鉴别了36种灵芝类产品。灵芝、孢子粉和菌丝体的红外谱图差别较显著;不同厂家所生产的灵芝产品由于所选用灵芝的产地不同、所用辅料的种类以及辅料所添加的多少不同,均引起了谱图的相对峰强度和波数位置的改变。结果表明:36种灵芝产品均可以根据红外的特征谱图进行分类鉴别。该方法快速、不需对灵芝产品进行分离提取。  相似文献   

17.
近红外光谱快速分析青贮饲料pH值和发酵产物   总被引:7,自引:0,他引:7  
刘贤  韩鲁佳  杨增玲  李琼飞 《分析化学》2007,35(9):1285-1289
采用近红外光谱技术,结合偏最小二乘回归法,研究了142个不同种类的秸秆青贮饲料样品的pH值和发酵产物(乳酸、乙酸、丙酸、丁酸和氨态氮),建立了干燥粉碎和新鲜样品的近红外漫反射光谱定量分析模型以及浸提液样品的近红外透射光谱定量分析模型。研究发现,pH值的近红外漫反射光谱和透射光谱的分析效果均较好,校正模型决定系数R2和验证集样品预测值与化学值的相关关系决定系数r2都大于0.80,并且干燥粉碎、新鲜和浸提液样品的RPD值分别为3.44、2.50和2.27;3种状态样品的乳酸、乙酸、丁酸和氨态氮的定量分析模型精度需进一步提高;R2在0.64~0.85之间;RPD值在1.38~1.93之间;丙酸含量的测定结果较差。方差分析显示,3种状态样品的测定结果之间均无显著性差异(P>0.05)。  相似文献   

18.
《Analytical letters》2012,45(16):2597-2609
A multistep infrared macro-fingerprint method was applied to identify two Chinese herbal drugs, Rhizoma Curcumas Longae (RCL) and Radix Curcumae (RC). Fourier transform infrared (FT-IR) spectra of the two were similar to each other and consistent with the 11 peaks of the spectrum of starch. RCL had a characteristic absorption peak at approximately 1514 cm?1 that correlated to the strong peak near 1509 cm?1 of curcumin. Between 900 cm?1–1700 cm?1 of the second derivative infrared (SD-IR) spectra, with higher resolution, RCL, and curcumin had 10 common peaks. In the FT-IR and SD-IR spectra of the ethanol extract, the spectra of the RCL extract and curcumin were similar, but RC was different. According to the fingerprint characteristics of the infrared spectra for RC and its extracts, the strongest peak at 1055 cm?1; the C-O absorption peaks at 1124 cm?1, 1106 cm?1, and 996 cm?1; and the strong methylene peaks at 2925 cm?1 and 2853 cm?1 suggest that RC contains more saccharides. In the range of 1350 cm?1–1700 cm?1, RCL and RC had similar two-dimensional infrared (2D-IR) correlation spectra. Both of them had three autopeaks, but the autopeaks were located at 1458 cm?1, 1560 cm?1, and 1641 cm?1 for RCL and 1458 cm?1, 1560 cm?1, and 1669 cm?1 for RC, suggested that the aromatic components of the two were not identical. The average correlation for the 18 RCL and 18 RC samples were 0.9906 and 0.9878, respectively, and this method achieves a good classification of the sample type.  相似文献   

19.
It is the most pressing task that fast and effective analysis methods monitor the inherent qualities of traditional Chinese medicine (TCM) and its corresponding extract products as a complicated mixture system. Owing to the unique fingerprint character and extensive applicability to test sample, infrared spectral method has been used in many research fields. In recent years, Fourier transform infrared spectroscopy (FT-IR), accompanied with the development of spectroscopic technology and combined with computer science, plays an important role in the TCM research. In this paper, we use FT-IR, second derivative infrared spectroscopy and two-dimensional correlation infrared spectroscopy (2D-IR) step by step to analyze the lipophilic constituents in Angelica extracted by two different extract crafts. As a result, all spectra can not only supply lots of structural information of main constituents in the complicated system, but also can differentiate the tiny differences between the similar systems according to the infrared macro-fingerprint characters. This is a very quick, effective and well repetitive method for monitoring the process of the TCM.  相似文献   

20.
Two-dimensional infrared (2D IR) spectroscopy is used to study atactic polystyrene. 2D IR is a technique based on time-resolved detection of IR signals in response to an external perturbation, such as mechanical strain. Since different chemical functional groups respond to the applied perturbation at unique and often different rates, characteristic time-dependent variations of the IR-band intensities are observed. Correlation analysis of the dynamic variation of the IR signals yields a new spectrum defined by two independent wave numbers. Peaks located on a 2D IR spectral plane imply interactions and connectivities among chemical functional groups. By spreading convoluted IR bands over two dimensions, the spectral resolution is also greatly enhanced.  相似文献   

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