共查询到20条相似文献,搜索用时 140 毫秒
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《化学研究》2021,32(3)
拉曼光谱因非接触、无损、指纹光谱特性,广泛应用于科学研究领域,主要集中于定性研究,拉曼光谱定量分析较为缺乏,尤其在液体中的定量分析研究明显不足。因此,有必要进一步开展水中拉曼光谱定量分析研究。探讨了将拉曼积分球应用于液体拉曼光谱定量分析技术,对水中SO_4~(2-)和HCO~-_3进行了定量分析可行性研究。定量分析基于内标法,选取水在~1 640 cm~(-1)附近的H-O-H的弯曲振动作为参照。实验结果表明,使用拉曼积分球的液相拉曼光谱定量分析技术有效地降低了SO_4~(2-)(0.1 mmol·L~(-1))和HCO~-_3(10 mmol·L~(-1))的检测限且具有良好的精度,可以用于定量分析水中的硫酸根与碳酸氢根浓度。 相似文献
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《理化检验(化学分册)》2010,(5)
综述了近年中应用光谱学方法研究小分子与牛血清白蛋白之间相互作用的进展,主要涉及紫外-可见吸收光谱法、傅里叶变换红外光谱法、分子荧光光谱法、拉曼光谱等方法的应用。还分析了这些方法各自的优势和今后的研究趋势(引用文献63篇)。 相似文献
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激光拉曼光谱内标法直接测定甲醇含量 总被引:1,自引:0,他引:1
《理化检验(化学分册)》2015,(4)
<正>激光拉曼光谱法作为一种新型无损检测技术,广泛应用于样品的定性、定量分析[1-3]。目前,样品中甲醇的定量分析方法常用的有气相色谱法[4]、分光光度法[5]和传感器法[6]等。本工作通过不同浓度的甲醇拉曼光谱特征峰(1 016.46cm-1)与乙醇的拉曼光谱特征峰(877.95cm-1)组成相对强度比,建立线性回归方程。本法具有测定简单、操作方便,无需添加其他化学试剂,可用于甲醇含量的直接检测。 相似文献
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《化学研究与应用》2017,(9)
应用拉曼光谱法并结合聚类分析对26种不同品牌、厂家、型号的塑钢窗进行了深入的检验研究。采用显微激光拉曼光谱分析技术分别对样品进行检测,得到在780nm激光光源的一阶导数扩展拉曼光谱中,塑钢窗的光谱形态差异显著,荧光背景干扰弱,重叠的谱峰得到有效的分离,可构建具有高鉴别能力的聚类分析模型,采集光谱数据将其定量化,选择离差平方和法作为类间距离,采用欧氏距离作为度量区间表征样品之间的亲疏程度,进行系统聚类分析,同时结合多种方法验证衡量聚类效果,成功将26种塑钢窗样本分为了18类,实现了基于全波段光谱信息结合系统聚类分析建立模型用于准确鉴定塑钢窗种类的目的,为现场物证的区分检验方法提供了一定的理论依据。 相似文献
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采用直流电弧法制备单壁碳纳米管样品,用457.5和632.8nm两种不同的激发光分别测得单壁碳纳米管的正常拉曼光谱和共振拉曼光谱.通过理论分析得到了单壁碳纳米管的直径分布,进一步推测了其类型及结构参数;对单壁碳纳米管的正切拉伸模的成分进行了归属.在632.8nm激发波长下得到了IG/ID值随激光功率变化的曲线,认为在2.5mW时,单壁碳纳米管缺陷的结构可能发生了改变.在用457.5nm波长激发的单壁碳纳米管的拉曼光谱中,首次发现了1421cm-1的拉曼谱峰. 相似文献
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应用激光拉曼光谱法对掺入其它植物油(如大豆油、花生油、玉米油、棕榈油或棉籽油)的核桃油进行检测。从上述6种纯植物油的拉曼光谱图中取6个主峰的相对拉曼光谱强度为变量进行主成分分析,从所得的二维散点图可知核桃油与其它5种油均分处于图的不同区域;对掺杂不同比例(质量分数)其它油品的核桃油,在其散点图中也可见两者分处不同区域,据此可对掺杂其它油品的核桃油作出定性鉴别。利用波数为1 256cm-1处拉曼光谱相对强度与掺杂油品的含量(w%)之间的线性关系及其所建立的线性回归方程,对掺杂的样品进行了定量分析。在纯核桃油中分别掺入质量分数从8%~95%的棕榈油制备了10份试样,按上述方法进行定量分析,结果表明预测值与已知值的相对误差在1.01%~2.35%之间。 相似文献
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Comparisons between LIBS and ICP/OES 总被引:3,自引:0,他引:3
In the framework of the development of new techniques, the ability of laser-induced breakdown spectroscopy (LIBS) to analyse
remotely complex aqueous solutions was investigated. The jet configuration with a collimated gas stream was chosen because
it appeared to be the most promising method for the LIBS probe, particularly in terms of sensitivity and repeatability. For
emission collection, the echelle spectrometer offers a simultaneously recorded wavelength range from the UV to the near IR
and is interesting for multielemental analysis for LIBS and also for inductively coupled plasma (ICP) optical emission spectroscopy
(OES). The importance of parameters influencing the quantitative results of LIBS such as multispecies analysis, sheath gas,
use of an internal standard and temporal parameters for analysis is described. LIBS quantitative data have been directly compared
with results from the more standard ICP/OES technique. 相似文献
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The performance indicators for a quantitative analysis (random and systematic uncertainties) are defined, and their origin in SIMS (secondary ion mass spectrometry) is discussed. The different methods for quantitative SIMS analysis: calibration curve approach, implanted standard method, relative sensitivity factor (RSF) method, are discussed. Examples are given for successful quantitative SIMS analyses of epilayers, implanted depth profiles and interface (IF) impurity distribution. In conclusion, a comparison is made between SIMS and other advanced techniques for thin film analysis. 相似文献
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雷宏田 《中国无机分析化学》2012,2(1):70-73
讨论了采用电感耦合等离子体发射光谱法测定铜合金中锆量分析结果不确定度产生的原因。建立了数学模型,对测量重复性,标准溶液,标准曲线变动,试液体积,试样称量,数字修约等引起的不确定分量进行评定,计算了合成标准不确定度和扩展不确定度,并给出铜合金中锆量测定结果的报告。评定结果表明:测量重复性,标准曲线线性回归引起的不确定度对总不确定度影响最大。所以在测定中应进行多次平行测定,特别注意标准曲线的校正和绘制校准曲线所用标准样品的选择。 相似文献
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Roberto-Jesús Lasheras Cristina Bello-Gálvez Miguel Escudero Jorge Cáceres 《Analytical letters》2017,50(8):1325-1334
In recent decades, numerous analytical techniques have been used for the analysis of archeological samples. Laser-induced breakdown spectroscopy (LIBS) is a promising technique due to its practically nondestructive nature and minimal sample preparation. In this work, LIBS was used for the qualitative and quantitative elemental analyses of pottery manufactured in ancient settlements of Rome. The qualitative study showed that the ceramics were composed of Fe, Ca, and Mg. For quantitative analysis, calibration curves of Fe, Ca, and Mg were constructed with reference samples of each element in a KBr matrix with zinc as an internal standard. The results obtained by LIBS were compared with values obtained by atomic absorption. 相似文献
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W. Demtr?der 《Fresenius' Journal of Analytical Chemistry》1990,337(7):830-834
Summary A review is given on different techniques in laser spectroscopy of atoms and molecules, which allow high spectral resolution and a very high detection sensitivity of small samples. Analytical applications of the techniques are discussed for basic scientific research, as well as for environmental problems and technical processes. Possible trends of laser spectroscopy, in particular with respect to applications in biology and medicine are shortly outlined. 相似文献
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《Analytical letters》2012,45(12):2163-2176
Abstract The purpose of the study was the quantitative determination of fluconazole by IR spectrophotometry which was realized by the application of the KBr disc technique. In this study dehydrocholic acid was used as internal standard. The absorption bands at 960 and 675 cm?1 were chosen for fluconazole and 1705 cm?1 for dehydrocholic acid. The concentration range between 0.4–1.6% w/w in KBr disc showed compliance with Beer's law. Besides IR spectroscopy, UV spectroscopy and HPLC methods were also used In the quantitative determinations. In the UV spectroscopy method the absorbance value at 261 nm in MeOH was used for fluconazole. In quantitative determinations which were performed by using HPLC, ketoconazole was the internal standard. Different regression equations were applied for each method in order to complete the quantitative determination. In UV spectroscopy and HPLC methods, relative standards were found as 0.74, 1.04% and in IR spectroscopy (675, 960 cm?1) relative standards were found as 1.1 and 1.51%, respectively. 相似文献
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板蓝根颗粒中蔗糖含量的红外光谱法测定 总被引:1,自引:0,他引:1
A method for rapid quantitative determination of sucrose in isatis-root granules by Fourier Transform Infrared Spectrophotometry(FTIR) was developed. Potassium ferricyanide was chosen as an inside mark material because it has only one strong absorption peak at 2117cm-1 and the peak was chosen as its quantitative peak. The peak at 1283cm-1 is the characteristic absorption of sucrose and was chosen as the quantitative peak of sucrose. The ratio of the two absorbances is I=Ai/As.K3[Fe(CN)6] and sucrose were mixed according to a certain mass ratio m=mi/ms to prepare standard samples. The curve of m versus I is the quantitative working curve. The linear range for sucrose is 5.0~23.0mg/g,the recovery is in the range of 91%~103%,the relative standard deviation is less than 5%. 相似文献
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The use of laser-induced breakdown spectroscopy for chemical analysis in the single-shot regime has been investigated for low-alloyed zinc samples. Several parameters that are important for plasma formation has been investigated and their importance for accurate and precise single-shot measurements are discussed. The standard deviation is compared for measurements performed on a day-to-day basis during four days and for a measurement series consisting of five measurements in one day. It was found that the spread is not larger for a measurement series performed on a single day compared to day-to-day basis. The influence of local spatial inhomogeneities of the alloy elements in the sample concentrations is discussed in this context and the reference samples have been investigated with a scanning electron microscopy and light optical microscopy to verify this. It is found that the relative standard deviation of the signal depends to large extent on the sample homogeneity at low concentrations. The importance of spatial averaging for LIBS when doing calibrations is established in this case. The relative error for single-shot measurements will depend on the slope of the analytical curve and increase at lower concentrations. 相似文献
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Szyszka R Hanton SD Henning D Owens KG 《Journal of the American Society for Mass Spectrometry》2011,22(4):633-640
Measuring the residual polyethylene glycol (PEG) in polyethylene oxide (PEO)-based surfactants is important to fully understanding
the performance of these materials. Traditional methods of quantitating PEG in PEO-based surfactants can be time-consuming
and struggle with low amounts or overlapping molecular mass distributions. This paper describes a matrix-assisted laser desorption/ionization
(MALDI) mass spectrometry method developed to quantitate residual PEG in a series of ethoxylated surfactants. The technique
addresses the difficulties faced in doing quantitative MALDI experiments by utilizing both internal standard and standard
additions protocols. The method produces excellent straight line standard addition plots, and the quantitative results are
verified using both a constructed standard and an independent traditional chromatographic separation. 相似文献