共查询到20条相似文献,搜索用时 62 毫秒
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一、前言 1928年印度物理学家C.V.拉曼(Raman)发现了拉曼效应。拉曼光谱学是以拉曼效应为基础发展起来的。拉曼光谱发展的前十年,在结构化学、分子光谱学的研究中发挥了重要作用。在这十年中间共发表了二千多篇文章,报导了四千余种化合物的拉曼光谱图。由于技术上的原因,拉曼光谱在实验技术和应用上都有相当的局限性。例如,样品用量大(通常要几十毫升)、曝光时间长(有时需数小时到几十小时)、并且仅限于做无色液体样品、受荧光干扰大等。然而,在六十年代初期,激光被用作拉曼光谱的激发光源之后,由于激光的优越性(能量大而集中,单色性好,偏振性能强),克 相似文献
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论述了激光拉曼光谱对高分子结构、结晶形态和表征,反应动力学过程和取向的研究,还介绍了纵向声学模、共振、高温高压、光波导和付里叶拉曼光谱在高分子研究中的最新进展。 相似文献
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激光、CCD检测器和光纤探针等相关技术的发展使激光拉曼光谱在生物医学领域中的研究进展日新月异,本文将从器官组织、细胞两方面进行分别阐述.前者立足于疾病诊断,探讨各种器官正常与病变组织的光谱差异及活体研究的现状及前景;后者以细胞为检测对象,介绍拉曼光谱的新方法和新进展. 相似文献
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首次从猪肝中提取、分离和纯化了二氢蝶啶还原酶(DHPR),并对猪肝二氢蝶啶还原酶冻干固体水溶液和重水溶液进行了激光拉曼光谱研究,测量了它们的拉曼光谱,对其主要拉曼特征频率进行初步指认,按照Lippert方法计算了它的α螺旋、β折叠和无序结构的相对百分含量。 相似文献
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在253K和16MPa的压力下,于实验室内合成了氮气水合物,用显微共焦拉曼光谱对其N-N和O-H键伸缩振动的光谱特征进行了研究.结果表明,氮气水合物中的N-N和O—H键的拉曼峰分别为2322.4和3092.1cm^-1,与天然的空气水合物中的数据十分接近.另外,还测定了液氮和溶解于水中的氮分子中N—N键的拉曼峰值,分别为2326.6和2325.0cm^-1.氮气笼型水合物分解的拉曼谱图表明,氮分子同时进入水合物的大笼和小笼中,但由于氮分子在大、小笼中的环境氛围十分接近,其拉曼位移相差不大,故拉曼谱图只能显示N—N键伸缩振动一个峰. 相似文献
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本文采用显微激光拉曼光谱对马氏珍珠贝和三角帆蚌贝壳进行了研究,结果表明,三角帆蚌贝壳珍珠层与棱柱层中的无机相皆与文石相,其中的有机相为类胡萝卜素类,马氏珍珠棱柱层中的无机相为方解石相,两种贝壳棱柱层晶体间的有机质中皆可能存在超微细的碳酸钙无机相。 相似文献
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Hong Shui-Li 《结构化学》1994,(1)
RamanSpectraofLaserCrystalsNABandNYABandtheLigandVibrationsofTheirActiveIons¥HongShui-Li(DepartmentofPhysics,FuzhouUniversity... 相似文献
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Raman spectra of liquid nitromethane were measured in single-shock experiments using transient Raman scattering system with high sensitivity. The measurement system was combined with a two-stage light gas gun to interrogate the vibrational mode-dependent behaviors of shock-compressed nitromethane molecules. Up to 12 GPa, all Raman peaks were able to be clearly detected, and showed the shock-induced shifting and broadening, but no signs of chemical changes occurred in the sample. Thus, it is concluded that chemical reactions could not be initiated in singly-shocked nitromethane below 12 GPa. 相似文献
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激光拉曼光谱内标法直接测定乙醇浓度 总被引:8,自引:3,他引:8
采用激光拉曼光谱对醇类样品中的乙醇含量进行直接测定。通过不同浓度乙醇的拉曼光谱特征峰(CCO面内伸缩振动884cm-1)与本底水峰组成相对强度比,建立线性回归方程,结果表明,线性范围为4%~40%,线性相关系数为0.9975;检出限为1.02%;回收率为82.0%~105.0%。对白酒、清酒、杨梅酒和医用酒精棉进行了测定,其乙醇平均浓度分别为36.1%、15.5%、23.7%和79.1%;RSD分别为0.22%、1.75%、2.49%和2.76%。此方法具有快速、简便、直接、绿色、对样品无损等优点,适用于白酒类、医用酒精等乙醇含量的检测。 相似文献
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The Raman spectra of 13 different carbohydrates are investigated by a laser Raman spectrometer. It is found the C—H stretching vibrations around 3000 cm−1 is the best region for qualitative analysis of these compounds. All compounds show an O—H stretching vibration around 3370 cm−1 which was not mentioned by earlier works. Excessive background noise appears in many spectra, probably due to their amorphous stuctures. 相似文献
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The polarized Raman spectra of naphthalene single crystal are recorded with a laser Raman spectrometer. Relative intensites of Raman lines in various polarizations are accurately measured by photon-counting technique. All the strong lines are polarized in the c′c′ and bb polarizations, and the polarization data alone are not sufficient to decide the symmetry of a Raman active vibration. The oriented gas model is found not adequate to fully understand the results. The polarization data have to be interpreted in terms of the electronic spectrum of naphthalene. 相似文献
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测量了不同温度下CCl4液芯光纤喇曼光谱强度,实验结果表明,光谱强度随着温度的变化存在着一个极大值,对影响光纤喇曼光谱强度的几个主要因素进行了估算,理论与实验结果符合较好。 相似文献
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While the halogen bond has been recognised and studied for over a hundred years, it is only in more recent times that chemists have begun to apply it and see its possibilities as another supramolecular interaction that can be deployed in the preparation of materials. This review takes one of those areas, liquid crystals, and considers examples of motifs that have been deployed successfully to generate new mesogens. In particular, rather than attempting to be comprehensive, the article reviews critically data from well-characterised systems and seeks to first make some comparisons with analogous hydrogen-bonded materials, before considering how the lability and flexibility of the halogen bond expresses itself in liquid crystal behaviour. 相似文献