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Process Characterization of the Transesterification of Rapeseed Oil to Biodiesel Using Design of Experiments and Infrared Spectroscopy
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作者 Tobias Drieschner Andreas Kandelbauer +1 位作者 Bernd Hitzmann Karsten Rebner 《Journal of Renewable Materials》 SCIE EI 2023年第4期1643-1660,共18页
For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the proc... For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the process and results in a mathematical description of the process behavior as a simple function based on the most important process factors can help to achieve higher production efficiency and quality.The present study aims at characterizing a well-known industrial process,the transesterification reaction of rapeseed oil with methanol to produce fatty acid methyl esters(FAME)for usage as biodiesel in a continuous micro reactor set-up.To this end,a design of experiment approach is applied,where the effects of two process factors,the molar ratio and the total flow rate of the reactants,are investigated.The optimized process target response is the FAME mass fraction in the purified nonpolar phase of the product as a measure of reaction yield.The quantification is performed using attenuated total reflection infrared spectroscopy in combination with partial least squares regression.The data retrieved during the conduction of the DoE experimental plan were used for statistical analysis.A non-linear model indicating a synergistic interaction between the studied factors describes the reactor behavior with a high coefficient of determination(R^(2))of 0.9608.Thus,we applied a PAT approach to generate further insight into this established industrial process. 展开更多
关键词 Process analytical technology TRANSESTERIFICATION design of experiment attenuated total reflection infrared spectroscopy partial least square regression
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Feasibility assessment of phenotyping cotton fiber maturity using infrared spectroscopy and algorithms for genotyping analyses 被引量:1
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作者 KIM Hee Jin LIU Yongliang +1 位作者 FANG David D. DELHOM Christopher D. 《Journal of Cotton Research》 2019年第1期44-55,共12页
Background:Cotton fiber maturity is an important property that partially determines the processing and performance of cotton.Due to difficulties of obtaining fiber maturity values accurately from every plant of a gene... Background:Cotton fiber maturity is an important property that partially determines the processing and performance of cotton.Due to difficulties of obtaining fiber maturity values accurately from every plant of a genetic population,cotton geneticists often use micronaire(MIC) and/or lint percentage for classifying immature phenotypes from mature fiber phenotyp es although they are complex fiber traits.The recent development of an algorithm for determining cotton fiber maturity(MIR)from Fourier transform infrared(FT-IR)spectra explores a novel way to measure fiber maturity efficiently and accurately.However,the algorithm has not been tested with a genetic population consisting of a large number of progeny pla,nts.Results:The merits and limits of the MIC-or lint percentage-bas ed phenotyping method were demonstrated by comparing the observed phenotypes with the predicted phenotypes based on their DNA marker genotypes in a genetic population consisting of 708 F2 plants with various fiber maturity.The observed MIC-based fiber phenotypes matched to the predicted phenotypes better than the observed lint percenta ge-based fiber phenotypes.The lint percentage was obtained from each of F2 plants,whereas the MIC values were unable to be obtained from the entire population since certain F2 plants produced insufficient fiber mass for their measurements.To test the feasibiility of cotton fiber infrared maturity(MIR)as a viable phenotyping tool for genetic analyses,we me asured FT-IR spectra from the second population composed of 80 F2 plants with various fiber maturities,determined MIR values using the algorithms,and compared them with their genotypes in addition to other fiber phenotypes.The results showed that MIR values were successfully obtained from each of the F2 plants,and the observed MIR-based phenotypes fit well to the predicted phenotypes based on their DNA marker genotypes as well as the observed phenotypes based on a combination of MIC and lint percentage.Conclusions:The M,R value obtained from FT-IR spectra of cotton fibers is able to accurately assess fiber maturity of all plants of a population in a quantitative way.The technique provides an option for cotton geneticists to determine fiber maturity rapidly and efficiently. 展开更多
关键词 attenuated total reflection Fourier transform infrared spectroscopy Cotton FIBER MATURITY CRYSTALLINITY IMMATURE FIBER (im) mutant
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Evaluation of Fourier Transform Infrared Spectroscopy for Diagnosis of Peroxisomal Diseases with Abnormal Very-Long-Chain Fatty Acid Metabolism
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作者 Minori Isogawa Satoshi Yoshida Nobuyuki Shimozawa 《American Journal of Analytical Chemistry》 2014年第6期359-366,共8页
Very long chain fatty acids (VLCFAs) are accumulated in cells and blood in patients with peroxisomal diseases, such as adrenoleukodystrophy (ALD) and Zellwger Syndrome (ZS). The purpose of this study is to investigate... Very long chain fatty acids (VLCFAs) are accumulated in cells and blood in patients with peroxisomal diseases, such as adrenoleukodystrophy (ALD) and Zellwger Syndrome (ZS). The purpose of this study is to investigate usefulness of Fourier transform infrared spectroscopy (FTIR) with attenuated total reflection (ATR) analysis method for clinical diagnosis of those diseases, thereby we measured the infrared spectra of the sera of patients and healthy controls. Correlation coefficients between 2nd derivative FTIR spectra of the serum samples and the VLCFA content ratio which is used as a clinical parameter to date were comprehensively calculated to investigate which wavenumber showed high correlation with the VLCFA ratio. Multiple regression analysis using the serum FTIR spectra showed that high correlations were observed with VLCFA ratios (C26:0/C22:0 ratio), and we could construct a suitable regression model (R2 = 0.97, p ﹣19). In addition, the model system using various VLCFAs in newborn bovine serum also showed that several FTIR peaks in 800 ~ 900 cm﹣1 region were found to have good correlation with VLCFA ratios. Our results support that FTIR analysis is useful for diagnosis of peroxisomal diseases. 展开更多
关键词 Fourier Transform infrared spectroscopy attenuated total reflection Very Long Chain FATTY ACIDS Peroxisomal DISEASES Multiple Regression Analysis
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LESS-INVASIVE LASER THERAPY AND DIAGNOSIS USING A TABLETOP MID-INFRARED TUNABLE LASER
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作者 HISANAO HAZAMA KATSUNORI ISHII KUNIO AWAZU 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2010年第4期285-292,共8页
Since numerous characteristic absorption lines caused by molecular vibration exist in the midinfrared(MIR)wavelength region,selective excitation or selective dissociation of molecules is possible by tuning the laser w... Since numerous characteristic absorption lines caused by molecular vibration exist in the midinfrared(MIR)wavelength region,selective excitation or selective dissociation of molecules is possible by tuning the laser wavelength to the characteristic absorption lines of target molecules.By applying this feature to the medical fields,less-invasive treatment and non-destructive diagnosis with absorption spectroscopy are possible using tunable MIR lasers.A high-energy nanosecond pulsed MIR tunable laser was obtained with difference-frequency generation(DFG)between a Nd:YAG and a tunable Cr:forsterite lasers.The MIR-DFG laser was tunable in a wavelength range of 5.5–10μm and generated laser pulses with energy of up to 1.4mJ,a pulse width of 5 ns,and a pulse repetition rate of 10 Hz.Selective removal of atherosclerotic lesion was successfully demonstrated with the MIR-DFG laser tuned at a wavelength of 5.75μm,which corresponds to the characteristic absorption of the ester bond in cholesterol esters in the atherosclerotic lesions.We have developed a non-destructive diagnostic probe with an attenuated total reflection(ATR)prism and two hollow optical fibers.An absorption spectrum of cholesterol was measured with the ATR probe by scanning the wavelength of the MIR-DFG laser,and the spectrum was in good agreement with that measured with a commercial Fourier transform infrared spectrometer. 展开更多
关键词 Mid-infrared tunable laser difference-frequency generation selective treatment attenuated total reflection spectroscopy hollow optical fiber
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BiI_3-nylon11纳米复合材料的XPS及ATR-IR分析 被引量:1
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作者 赵志娟 刘芬 赵良仲 《分析测试技术与仪器》 CAS 2011年第1期42-46,共5页
用X射线光电子能谱法(XPS)测定了BiI3与nylon11作用生成纳米复合材料后聚合物中酰胺基团的N、O内层能级电子结合能变化,同时用衰减全反射红外光谱法(ATR-IR)研究了BiI3-nylon11复合材料中BiI3对尼龙酰胺基团之间氢键作用的影响.结果表明... 用X射线光电子能谱法(XPS)测定了BiI3与nylon11作用生成纳米复合材料后聚合物中酰胺基团的N、O内层能级电子结合能变化,同时用衰减全反射红外光谱法(ATR-IR)研究了BiI3-nylon11复合材料中BiI3对尼龙酰胺基团之间氢键作用的影响.结果表明,与纯nylon11聚合物相比,BiI3-nylon11纳米复合材料中N1s、O1s的结合能要稍高一些;N-H伸缩振动、酰胺I谱带、酰胺Ⅱ谱带振动频率在X射线照射前均发生显著位移,而X射线照射后没有明显的变化,只是谱带变宽.另一方面,无论X射线照射与否,CH2伸缩振动基本不变.实验所得结果对于理解聚合物中氢键相互作用及其对复合材料的结构和性能的影响有一定意义。 展开更多
关键词 纳米复合材料 X射线光电子能谱 衰减全反射红外光谱
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基于衰减全反射LED光谱的g-C_(3)N_(4)对亚甲基蓝表面的吸附
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作者 王思祺 洪雯雯 +3 位作者 卜义夫 邵梦莎 李静怡 刘思乐 《印染助剂》 CAS 2024年第3期32-37,共6页
以SiO_(2)光导纤维为载体,通过溶胶-凝胶法将g-C_(3)N_(4)负载在SiO_(2)光导纤维表面形成一层均匀的薄膜,采用X射线衍射(XRD)、红外光谱(FT-IR)、扫描电镜(SEM)、瞬态荧光光谱(PL)、荧光电镜(LSCM)、Zeta电位等表征技术对样品进行表征... 以SiO_(2)光导纤维为载体,通过溶胶-凝胶法将g-C_(3)N_(4)负载在SiO_(2)光导纤维表面形成一层均匀的薄膜,采用X射线衍射(XRD)、红外光谱(FT-IR)、扫描电镜(SEM)、瞬态荧光光谱(PL)、荧光电镜(LSCM)、Zeta电位等表征技术对样品进行表征。结果表明:g-C_(3)N_(4)均匀分布在SiO_(2)光导纤维表面,吸附亚甲基蓝分子后Zeta电位由-45.35 mV升高到-28.72 mV;FT-IR光谱中700 cm^(-1)处的吸收峰移动到667 cm^(-1)处,600 cm^(-1)处的吸收峰消失;PL光谱典型发射峰明显下降,这都说明了g-C_(3)N_(4)对亚甲基蓝分子有较好的吸附能力。利用SiO_(2)光导纤维对光全反射的特点并借助衰减全反射光谱原理,以红光LED为光源,光电倍增管为检测器,研究了g-C_(3)N_(4)对亚甲基蓝分子的表面吸附,采用Freundlich等温吸附模型和Langmuir等温吸附模型对实验结果进行了拟合。结果表明:g-C_(3)N_(4)对亚甲基蓝分子的吸附更符合Langmuir等温吸附模型,属于单分子层吸附而非多分子层吸附。 展开更多
关键词 衰减全反射LED光谱 g-C_(3)N_(4) SiO_(2)光导纤维 亚甲基蓝 表面吸附
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Chemometric Feature Selection and Classification of <i>Ganoderma lucidum</i>Spores and Fruiting Body Using ATR-FTIR Spectroscopy 被引量:2
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作者 Ying Zhu Augustine Tuck Lee Tan 《American Journal of Analytical Chemistry》 2015年第10期830-840,共11页
Ganoderma lucidum(G. lucidum) spores as a valuable Chinese herbal medicine have vast marketable prospect for its bioactivities and medicinal efficacy. This study aims at the development of an effective and simple anal... Ganoderma lucidum(G. lucidum) spores as a valuable Chinese herbal medicine have vast marketable prospect for its bioactivities and medicinal efficacy. This study aims at the development of an effective and simple analytical method to distinguish G. lucidum spores from its fruiting body, which is of essential importance for the quality control and fast discrimination of raw materials of Chinese herbal medicine. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy combined with the appropriate chemometric methods including penalized discriminant analysis, principal component discriminant analysis and partial least squares discriminant analysis has been proven to be a rapid and powerful tool for discrimination of G. lucidum spores and its fruiting body with classification accuracy of 99%. The model leads to a well-performed selection of informative spectral absorption bands which improve the classification accuracy, reduce the model complexity and enhance the quantitative interpretations of the chemical constituents of G. lucidum spores regarding its anticancer effects. 展开更多
关键词 Feature Selection attenuated total reflection Fourier Transform infrared spectroscopy Penalized Linear DISCRIMINANT ANALYSIS Principal Component DISCRIMINANT ANALYSIS Partial Least Squares DISCRIMINANT ANALYSIS
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ATR-IR分析氢氧化钠对水及离子液体/水体系氢键作用的影响
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作者 倪柳芳 余璟 +4 位作者 汪心娉 王俊 曹小霞 曹石林 马晓娟 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2021年第10期3106-3110,共5页
利用衰减全反射红外光谱(ATR-IR)分析NaOH对水及1-乙基-3-甲基咪唑醋酸酯离子液体水溶液(EmimAc/水)氢键网络的影响,研究结果表明,NaOH的加入会影响水分子的氢键对称性和类型,对称性氢键谱带Ⅰ(3218 cm^(-1))和Ⅱ(3375 cm^(-1))随着NaO... 利用衰减全反射红外光谱(ATR-IR)分析NaOH对水及1-乙基-3-甲基咪唑醋酸酯离子液体水溶液(EmimAc/水)氢键网络的影响,研究结果表明,NaOH的加入会影响水分子的氢键对称性和类型,对称性氢键谱带Ⅰ(3218 cm^(-1))和Ⅱ(3375 cm^(-1))随着NaOH浓度的提高而降低。NaOH使水溶液氢键发生极化,产生连续吸收带,连续吸收带随着NaOH浓度的提高而增强。水对EmimAc的阳离子和阴离子均有影响。水分子的OH和EmimAc的COO-产生强的相互作用,在3400~3200 cm^(-1)产生宽的吸收谱带;而水分子的质子和COO-作用使得C=O吸收谱带红移。水的加入使得EmimAc指纹区的谱带蓝移或吸收强度下降,表明水可以破坏EmimAc原有的氢键网络,形成“阴离子…HOH…阴离子”团簇,减弱了离子液体阴、阳离子之间的相互作用。NaOH替代水与EmimAc混合,ATR-IR谱图的变化并不显著,主要表现在谱带的吸收强度上。与EmimAc/水相比,EmimAc/NaOH水溶液的ATR-IR谱的吸收强度更高,表明NaOH水溶液对EmimAc氢键网络的破坏不如水显著。由此可见,可利用EmimAc/NaOH体系降低离子液体体系黏度,并且降低离子液体使用成本,对木质纤维原料预处理有一定的指导意义。 展开更多
关键词 1-乙基-3-甲基咪唑醋酸酯 氢氧化钠溶液 衰减全反射红外光谱
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Deliquescence and Efflorescence Processes of Aerosol Particles Studied by in situ FTIR and Raman Spectroscopy
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作者 Li-jun Zhao Feng Wang +2 位作者 Kun Zhang Qing-xuan Zeng Yun-hong Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第1期1-11,共11页
伞状和开花是喷雾器粒子的二个很重要的物理化学的过程。在伞状和喷雾器粒子的开花周期,许多基本问题需要在分子的水平上详细被调查,包括在使过饱和的喷雾器,可以被形成的亚稳的稳固的阶段,和显微镜的结构和喷雾器粒子的伞状机制的... 伞状和开花是喷雾器粒子的二个很重要的物理化学的过程。在伞状和喷雾器粒子的开花周期,许多基本问题需要在分子的水平上详细被调查,包括在使过饱和的喷雾器,可以被形成的亚稳的稳固的阶段,和显微镜的结构和喷雾器粒子的伞状机制的离子和分子相互作用。这份报纸论述在伞状的最近的调查和喷雾器粒子的开花过程取得由的进步的一篇摘要四普通光谱技术,作为 Raman/electrodynamic 平衡被知道,石英底层上的 Fourier 变换 infrared/aerosol 流动试管, Fourier 变换 infrared/attenuated 总数思考,和共焦的拉曼。 展开更多
关键词 气溶胶 风化 潮解 分子光谱学
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基于滤波器的动植物油光谱信号预处理方法比较及识别分类
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作者 邱薇纶 丁圣 《食品与发酵工业》 CAS CSCD 北大核心 2023年第8期281-288,共8页
为实现对动植物油的快速无损检验,探究滤波器在提高光谱分析模型区分能力方面的可行性,该研究借助衰减全反射-表面增强红外吸收光谱技术,采集了动物油(159份)和植物油(188份)共计347份样本的光谱信息数据,构建了Fisher判别分析、支持向... 为实现对动植物油的快速无损检验,探究滤波器在提高光谱分析模型区分能力方面的可行性,该研究借助衰减全反射-表面增强红外吸收光谱技术,采集了动物油(159份)和植物油(188份)共计347份样本的光谱信息数据,构建了Fisher判别分析、支持向量机和决策树3种分类模型。比较了希尔伯特变换、有限长单位脉冲响应滤波器、无限长冲激响应滤波器、快速傅里叶变换和小波变换5种滤波器对3种分类模型精度的影响,同时考察了滤波器窗函数(矩形窗、汉宁窗、海明窗、布莱克曼窗)、小波基函数(Morlet、Dgauss、Mexhat、Haar、Daubechies、Biorthogonal)、滤波方式(低通、高通、带通、带阻)在动植物油样本区分效果方面的差异性。结果发现,滤波器能显著提升光谱分析模型的准确性,低通和带阻滤波方式,矩形窗和布莱克曼窗函数能有效提升模型对样本的区分能力,相较于其他2种算法,支持向量机对各样本的识别区分能力最好。基于FIR低通/带阻滤波器处理后构建的SVM模型(RBF核函数)可作为动植物油样本识别的最佳模型,其对347份样本实现了100%的“类别-品牌”的两级准确区分。综上,滤波器可有效提升光谱分析模型的准确性,结合ATR-SEIRAS光谱信息数据,可准确区分不同的动植物油样本,这为包括动植物油在内的诸多样本的快速无损分析提供了一定参考,为滤波器在提升光谱分析模型方面的应用提供了一定借鉴。 展开更多
关键词 动植物油 衰减全反射-表面增强红外吸收光谱 滤波器 FISHER判别分析 支持向量机 决策树
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ATR-FTIR结合DSC法快速鉴别食品接触用塑料包装制品 被引量:1
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作者 毛月红 刘建涛 张黎明 《塑料包装》 CAS 2023年第2期30-34,共5页
研究了一种衰减全反射红外光谱(ATR-FTIR)结合差示扫描量热法(DSC)快速鉴别食品接触用塑料包装制品单一材质的方法。红外光谱图能准确反应塑料制品的内部结构,结合DSC曲线得出其具体成分。该方法快速、准确且几乎不破坏样品。
关键词 食品接触用塑料包装制品 衰减全反射红外光谱法(ATR-FTIR) 差示扫描量热法(DSC) 鉴别
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基于ATR-FTIR研究药食同源植物多花黄精的产地分布
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作者 蒋芙蓉 江星明 +3 位作者 黄良辉 夏新斌 何雄 袁志鹰 《湖南中医药大学学报》 CAS 2023年第5期864-868,共5页
目的基于傅里叶变换衰减全反射红外光谱(attenuated total reflection-flourier transformed infrared spectroscopy,ATR-FTIR)研究药食同源植物多花黄精的产地分布。方法采用ATR-FTIR技术采集不同产地多花黄精粉末样本的红外光谱数据,... 目的基于傅里叶变换衰减全反射红外光谱(attenuated total reflection-flourier transformed infrared spectroscopy,ATR-FTIR)研究药食同源植物多花黄精的产地分布。方法采用ATR-FTIR技术采集不同产地多花黄精粉末样本的红外光谱数据,通过红外谱图的波数分析其对应的官能团,并进行精密度、重复性、稳定性的方法学考察试验。谱图数据经预处理后,建立主成分分析(principal components analysis,PCA)模型和正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)模型,进行多元统计数据分析。结果不同产地多花黄精ATR-FTIR图谱的峰形、峰位差异微小。运用PCA和OPLS-DA可视化处理不同产地多花黄精的数据,发现7种不同产地多花黄精代谢轮廓差异明显,可对不同产地的多花黄精进行辅助鉴别。结论ATR-FTIR技术操作简单,环保经济,可为多花黄精质量控制提供技术参考。 展开更多
关键词 多花黄精 傅里叶变换衰减全反射红外光谱 正交偏最小二乘判别分析 产地 质量控制
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原油环境下螺杆泵定子材料的化学损伤
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作者 李鸿泰 王超 +1 位作者 张子成 谈金祝 《合成橡胶工业》 CAS 北大核心 2023年第6期482-487,共6页
以氢化丁腈橡胶为原材料制备了螺杆泵定子材料,通过模拟真实采油环境并使用显微镜、衰减全反射傅里叶变换红外光谱仪研究了螺杆泵定子材料在不同温度原油环境下的化学老化损伤情况,探究了螺杆泵定子材料在原油环境下的化学损伤机理。结... 以氢化丁腈橡胶为原材料制备了螺杆泵定子材料,通过模拟真实采油环境并使用显微镜、衰减全反射傅里叶变换红外光谱仪研究了螺杆泵定子材料在不同温度原油环境下的化学老化损伤情况,探究了螺杆泵定子材料在原油环境下的化学损伤机理。结果表明,原油温度和老化时间对氢化丁腈橡胶材料的化学老化损伤有重要影响,在相同老化时间下,螺杆泵定子材料的质量变化率随着原油温度的升高而增加,而在相同老化温度下,螺杆泵定子材料的质量变化率随着老化时间的延长而增加且增速趋缓;螺杆泵定子材料在25℃原油环境下的化学损伤机理主要以分子链的断裂和碳链的氧化交联为主,在60℃原油环境下的化学损伤机理主要包括分子链的断裂、碳链的氧化交联及腈基的氧化交联,而在100℃原油环境下的化学损伤机理主要包括分子链的断裂、碳链的氧化交联反应、腈基的氧化交联反应和腈基间因高温而引发的交联反应。 展开更多
关键词 螺杆泵定子材料 氢化丁腈橡胶 原油环境 质量变化率 衰减全反射傅里叶变换红外光谱 化学老化损伤 损伤机理
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不同采收月份唐古特大黄多元红外光谱判别
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作者 冯丹 龙若兰 +2 位作者 李佩佩 李朵 孙菁 《中成药》 CAS CSCD 北大核心 2023年第3期836-842,共7页
目的建立多元红外光谱条件下不同月份唐古特大黄判别方法,为鉴别大黄药材的采收期提供科学依据。方法以不同采收月份唐古特大黄根部为研究对象,分别采集其中红外光谱(MIR)、衰减全反射红外光谱(ATR)、近红外光谱(NIR),分别建立3种不同... 目的建立多元红外光谱条件下不同月份唐古特大黄判别方法,为鉴别大黄药材的采收期提供科学依据。方法以不同采收月份唐古特大黄根部为研究对象,分别采集其中红外光谱(MIR)、衰减全反射红外光谱(ATR)、近红外光谱(NIR),分别建立3种不同红外光谱信息下的月份判别模型。结果不同月份谱图在峰位置与峰强的差异较大。在不同红外光谱信息下的月份判别模型中,以NIR谱图所建判别模型效果最好,其模型识别率、预测率、总和均达到100%,外部测试集识别率为85.19%。结论利用NIR定性检测模型,可以实现不同月份唐古特大黄药材的快速判别,可用于指导药材的采收。 展开更多
关键词 唐古特大黄 月份判别 近红外光谱 中红外光谱 衰减全反射红外光谱
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Possible Relevance of the Allende Meteorite Conditions in Prebiotic Chemistry: An Insight into the Chondrules and Organic Compounds
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作者 Alejandro Heredia Barbero Héctor G. Vázquez López +8 位作者 Adriana L. Meléndez López Jorge A. Cruz Castañeda Daniel Luna Laviada Karina E. Cervantes de la Cruz Victor Meza Laguna Vladimir A. Basiuk Ivonne Rosales Chávez Alicia Negrón Mendoza Sergio Ramos Bernal 《Advances in Biological Chemistry》 2023年第3期82-99,共18页
The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the... The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the magnetic minerals present in ordinary and carbonaceous chondrites, providing information on the evolution of magnetic fields. The interaction of organic compounds with magnetic minerals is a possible source of chemical diversity, which is crucial for molecular evolution. Carbon compounds in meteorites are of great scientific interest for a variety of reasons, such as their relevance to the origins of chirality in living organisms. This study presents the characterization of organic and mineral compounds in the Allende meteorite. The structural and physicochemical characterization of the Allende meteorite was accomplished through light microscopy, powder X-ray diffraction with complementary Rietveld refinement, Raman and infrared spectroscopy, mass spectrometry, scanning electron microscopy, and atomic force microscopy using magnetic signal methods to determine the complex structure and the interaction of organic compounds with magnetic Ni-Fe minerals. The presence of Liesegang-like patterns of chondrules in fragments of the Allende structure may also be relevant to understanding how the meteorite was formed. Other observations include the presence of magnetic materials and nanorod-like solids with relatively similar sizes as well as the heterogeneous distribution of carbon in chondrules. Signals observed in the Raman and infrared spectra resemble organic compounds such as carbon nanotubes and peptide-like molecules that have been previously reported in other meteorites, making the Mexican Allende meteorite a feasible sample for the study of the early Earth and exoplanetary bodies. 展开更多
关键词 Allende Meteorite Carbonaceous Chondrite Light Microscopy X-Ray Diffraction with the Rietveld Method Raman spectroscopy attenuated total reflectance infrared spectroscopy Mass Spectrometry Scanning Electron Mi-croscopy Energy Dispersive X-Ray spectroscopy Magnetic Force Microscopy
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衰减全反射红外光谱法鉴定药品包装材料材质
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作者 陈水廷 刘颖玲 聂蕾 《化学分析计量》 CAS 2023年第11期89-93,共5页
利用衰减全反射-红外光谱法对药用高密度聚乙烯瓶、药用聚丙烯瓶、药用聚酯瓶、聚氯乙烯固体药用硬片、注射用丁基橡胶塞5种常见的药品包装材料进行鉴定。对所得图谱中的主要特征峰进行归属,其中高密度聚乙烯瓶主要有2 916、2 848、1 47... 利用衰减全反射-红外光谱法对药用高密度聚乙烯瓶、药用聚丙烯瓶、药用聚酯瓶、聚氯乙烯固体药用硬片、注射用丁基橡胶塞5种常见的药品包装材料进行鉴定。对所得图谱中的主要特征峰进行归属,其中高密度聚乙烯瓶主要有2 916、2 848、1 472、1 462、730、719 cm^(-1)6个特征吸收峰;药用聚丙烯瓶主要有2 950、2 917、2 867、2 837、1 456、1 376、1 359、1 167、997、973、899、841、808 cm^(-1)13个特征吸收峰;药用聚酯瓶主要有1 715、1 409、1 243、1 097、1 017、872、793、723 cm^(-1)8个特征吸收峰;聚氯乙烯固体药用硬片主要有2 962、2 918、2 851、1 733、1 426、1 328、1 253、1 195、1 109、965、832、697 cm^(-1)12个特征吸收峰;注射用丁基橡胶塞有2 950、2 895、1 469、1 389、1 365、1 228、1 086、800 cm^(-1)8个特征吸收峰,从而得到相对应的特征红外图谱。建立了实验室内部的药品包装材料光谱数据库,便于对不能提供其产品红外对照图谱的药品包装材料进行鉴别。 展开更多
关键词 衰减全反射-红外光谱法 药品包装材材 特征峰
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基于太赫兹衰减全反射光谱的固体乳糖测试
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作者 刘金鸽 吴玫晓 +4 位作者 刘锋 施杰 王丹 刘友明 杨旻蔚 《太赫兹科学与电子信息学报》 2023年第3期311-316,共6页
利用衰减全反射式太赫兹时域光谱技术研究了固态α-乳糖的光谱特性,首先实验以传统透射式光谱技术为基准,获得了0.53 THz,1.36 THz 2个较强的吸收峰;其次,取剂量分别为1.8 mg+2.56 mg与1.8 mg的α-乳糖,利用衰减全反射式太赫兹时域光谱... 利用衰减全反射式太赫兹时域光谱技术研究了固态α-乳糖的光谱特性,首先实验以传统透射式光谱技术为基准,获得了0.53 THz,1.36 THz 2个较强的吸收峰;其次,取剂量分别为1.8 mg+2.56 mg与1.8 mg的α-乳糖,利用衰减全反射式太赫兹时域光谱系统获得吸收谱线,在0.53 THz,1.36 THz均有较强吸收峰,增加样品剂量对0.53 THz,1.36 THz处吸收强度未产生影响;最后取相同剂量的2份α-乳糖,一份过筛至75μm,另一份未过筛,利用衰减全反射式太赫兹时域光谱系统获得吸收谱线,在0.53 THz,1.36 THz均有较强吸收峰;减小样品颗粒度,在0.53 THz,1.36 THz附近吸收强度增加。 展开更多
关键词 太赫兹时域光谱系统 衰减全反射 α-乳糖
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傅里叶变换衰减全反射红外光谱法的应用与进展 被引量:35
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作者 徐琳 王乃岩 +1 位作者 霸书红 王云龙 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2004年第3期317-319,共3页
随着傅里叶变换红外光谱仪的应用及化学计量学的发展 ,傅里叶变换衰减全反射红外光谱法(ATR FTIR)成为用传统透过法制样效果不理想 (或制样复杂 )的样品及表层结构分析的有利工具和手段。ATR FTIR技术已应用到纺织、质检、公安等各个领... 随着傅里叶变换红外光谱仪的应用及化学计量学的发展 ,傅里叶变换衰减全反射红外光谱法(ATR FTIR)成为用传统透过法制样效果不理想 (或制样复杂 )的样品及表层结构分析的有利工具和手段。ATR FTIR技术已应用到纺织、质检、公安等各个领域。目前 ,人们正在针对ATR FTIR的特性 ,开展应用研究。为此 ,文章主要介绍了国内外应用ATR FTIR技术进行深度剖析的研究 ,对材料表面的定性分析 ,组分的定量分析 ,光学纤维与ATR附件的联用技术 ,以及在其他领域 (如运用ATR FTIR技术考察中空纤维的结构及取向变化 ,研究皮肤促进剂的作用机理 ) 展开更多
关键词 傅里叶变换衰减全反射红外光谱法 ATR-FTIR 高分子材料 定性分析 定量分析 光学纤维
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傅立叶变换拉曼光谱和红外光谱鉴别塑料 被引量:30
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作者 窦艳丽 张万喜 +3 位作者 张玉杰 周华 汪冬梅 徐经伟 《分析化学》 SCIE EI CAS CSCD 北大核心 2006年第11期1615-1618,共4页
用傅立叶变换拉曼光谱、衰减全反射红外光谱和近红外光谱结合OPUS/Ident软件对添加不同填料、不同助剂的塑料进行鉴别分类。结果表明:分子光谱结合化学计量学鉴别塑料是一种快速可靠的方法。其中拉曼光谱和衰减全反射红外光谱能够直接... 用傅立叶变换拉曼光谱、衰减全反射红外光谱和近红外光谱结合OPUS/Ident软件对添加不同填料、不同助剂的塑料进行鉴别分类。结果表明:分子光谱结合化学计量学鉴别塑料是一种快速可靠的方法。其中拉曼光谱和衰减全反射红外光谱能够直接区分样品,而近红外光谱非常类似,不能直接区分。但是用OPUS/Ident软件中的W ard算法处理这3种光谱后,得到的树形图能够将样品准确分类。 展开更多
关键词 傅立叶变换拉曼光谱 衰减全反射红外光谱 近红外光谱 聚类分析 塑料
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中红外、近红外和拉曼光谱法测定商品农药制剂中氰戊菊酯和马拉硫磷的含量 被引量:17
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作者 熊艳梅 唐果 +2 位作者 段佳 李春子 闵顺耕 《分析化学》 SCIE CAS CSCD 北大核心 2012年第9期1434-1438,共5页
利用近红外、中红外和拉曼光谱法定量分析了商品农药制剂中有效成分氰戊菊酯和马拉硫磷的含量。采用偏最小二乘法(Partial least squares,PLS)建立氰戊菊酯和马拉硫磷的定量模型并进行了优化,用独立检验集对模型适应性进行评价。近红外... 利用近红外、中红外和拉曼光谱法定量分析了商品农药制剂中有效成分氰戊菊酯和马拉硫磷的含量。采用偏最小二乘法(Partial least squares,PLS)建立氰戊菊酯和马拉硫磷的定量模型并进行了优化,用独立检验集对模型适应性进行评价。近红外和中红外法测定氰戊菊酯、马拉硫磷定量模型的相关系数分别是0.9981,0.9994和0.9946,0.9998,外部验证集标准差分别是0.082,0.081和0.092,0.075,两种方法的定量效果接近;拉曼法氰戊菊酯和马拉硫磷定量模型的相关系数分别为0.9872和0.9993,外部验证集标准差分别为0.254和0.317,预测精度不及近红外和中红外法高。MIR-ATR,NIR和Raman 3种方法均能满足现场检测农药质量的需要。 展开更多
关键词 近红外光谱 中红外光谱 拉曼光谱 农药制剂 偏最小二乘法 氰戊菊酯 马拉硫磷
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