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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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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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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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Estimation of Postmortem Interval Using Attenuated Total Reflectance:Fourier Transform Infrared Spectroscopy in Adipose Tissues
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作者 Haohui Zhang Qi Wang +3 位作者 Kai Zhang Ruina Liu Shuanliang Fan Zhenyuan Wang 《Journal of Forensic Science and Medicine》 2019年第1期7-12,共6页
Estimation of postmortem interval(PMI)is vitally important in forensic investigations.Although many studies have examined the chemical changes of various tissues over time,no reports using spectroscopic methods in adi... Estimation of postmortem interval(PMI)is vitally important in forensic investigations.Although many studies have examined the chemical changes of various tissues over time,no reports using spectroscopic methods in adipose tissue are available.In this study,attenuated total reflectance-Fourier transform infrared(ATR-FTIR)spectroscopy was utilized to collect comprehensive biochemical information from human adipose tissues in vitro at different times.Thereafter,mice were used as samples for in vivo experiments for more detailed studies on PMI.Then,partial least squares(PLS)model for PMI estimation was established based on the acquired spectral dataset of mouse samples.The spectral variable associated with C=O arising from lipids and free fatty acids was most susceptible to PMI.Moreover,the PLS model appeared to achieve a satisfactory prediction with a root mean square error of cross‑validation of 1.78 days,and the reliability of the model was determined in an external validation set with a root mean square error of prediction of 1.87 days.The study shows the possibility of application of ATR-FTIR methods in PMI estimation using adipose tissue. 展开更多
关键词 Adipose tissue attenuated total reflectance-Fourier transform infrared CHEMOMETRICS postmortem interval
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应用衰减全反射红外光谱无损鉴别中国传统手工纸的方法研究
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作者 吕淑贤 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第9期2450-2458,共9页
纤维种类鉴别是古代纸张保护的重要基础工作。探究中国传统手工纸的无损纤维鉴别的方法对中国古籍、档案及纸质文物的研究和保护具有重要意义。该研究应用衰减全反射傅里叶变换红外光谱(ATRFTIR)对已知纤维成分的17类64种中国传统手工... 纤维种类鉴别是古代纸张保护的重要基础工作。探究中国传统手工纸的无损纤维鉴别的方法对中国古籍、档案及纸质文物的研究和保护具有重要意义。该研究应用衰减全反射傅里叶变换红外光谱(ATRFTIR)对已知纤维成分的17类64种中国传统手工纸标准样品进行了无损分析,参考纤维素和木质素的红外峰位及部分纸样的X射线衍射(XRD)分析结果确认纸样中的所有红外谱峰归属;并采用分波段比较分析的方法对相似度极高的谱图进行比对分析,分别总结各类纸张在4000~1800、1800~1500、1500~1200和1200~600cm^(-1)四个波段的谱图特征;同时对4cm^(-1)精度的谱图进行二阶导数处理,分别总结各类纸张在1500~1200和1200~900cm^(-1)两个波段的二阶导数谱图特征;最后通过红外结晶指数及其他峰高和峰面积比值计算结果实现对纸类更细致的区分。应用上述方法对16个盲测样品进行了有效性测试,红外分析结果与显微纤维鉴别结果一致,初步证明了该方法在中国传统手工纸无损纤维鉴别上的可行性和有效性。实验结果表明,应用ATR-FTIR无损分析法可对麻、桑构皮、檀皮、瑞香皮和竹几大类原料的传统手工纸纤维类型作出快速而准确的鉴别,对于混料的宣纸也同样适用;但对于显微分析也难以鉴别的亲缘关系较近的植物原料如桑、构皮之间的精细鉴别仍有一定局限性。 展开更多
关键词 衰减全反射傅里叶变换红外光谱 二阶导数红外光谱 中国传统手工纸 纤维鉴别 无损分析
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基于近红外光谱特征的冷冻小龙虾鲜度快速检测方法 被引量:1
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作者 占可 陈季旺 +3 位作者 徐言 倪杨帆 刘言 邹圣碧 《食品科学》 EI CAS CSCD 北大核心 2024年第2期299-307,共9页
为建立快速检测冷冻小龙虾鲜度的近红外光谱模型,采集解冻的小龙虾虾尾、虾仁及虾糜的近红外光谱,分别利用一阶导数、多元散射校正、小波变换(wavelet transform,WT)和标准正态变换进行预处理,并利用偏最小二乘(partial least squares,P... 为建立快速检测冷冻小龙虾鲜度的近红外光谱模型,采集解冻的小龙虾虾尾、虾仁及虾糜的近红外光谱,分别利用一阶导数、多元散射校正、小波变换(wavelet transform,WT)和标准正态变换进行预处理,并利用偏最小二乘(partial least squares,PLS)与卷积神经网络(convolutional neural network,CNN)算法将预处理前后的光谱数据分别与总挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量关联,构建定量预测模型并比较建模效果,选取较佳模型,探究模型预测准确度和适用性。结果显示,预处理方法明显影响了建立模型的精度,光谱经预处理建立的CNN模型与PLS模型相比,具备更好地预测小龙虾TVB-N含量的能力。其中,虾仁光谱经WT预处理建立的CNN模型对验证集的预测准确度最高,校正集与验证集的相关系数分别为0.97、0.96,校正集与验证集的均方根误差分别为1.26、0.93mg/100g。近红外光谱的准确度、精密度与灵敏度均在合理范围内,方法学验证结果良好。综合考虑实际应用中快速、准确、低损伤等需求,确定WT-CNN-虾仁模型为预测冷冻小龙虾中TVB-N含量的最优模型。这些结果表明,WT-CNN-虾仁模型在预测冷冻小龙虾TVB-N含量、快速评价新鲜度方面具有巨大潜力。 展开更多
关键词 近红外光谱 小龙虾 总挥发性盐基氮 快速检测 卷积神经网络 小波变换
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原位衰减全反射表面增强红外光谱示踪单原子催化二氧化碳电还原反应中间体的研究进展
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作者 严靖 倪嘉琪 +2 位作者 孙宏丽 苏陈良 刘彬 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第7期32-52,共21页
电催化二氧化碳还原反应(CO_(2)RR)涉及多个电子和质子转移,动态演变过程复杂.具有结构简单性和均匀性的单原子催化剂(SACs)是研究上述复杂过程的理想模型催化剂,有利于理解催化构效关系.原位衰减全反射表面增强红外光谱技术为识别单原... 电催化二氧化碳还原反应(CO_(2)RR)涉及多个电子和质子转移,动态演变过程复杂.具有结构简单性和均匀性的单原子催化剂(SACs)是研究上述复杂过程的理想模型催化剂,有利于理解催化构效关系.原位衰减全反射表面增强红外光谱技术为识别单原子催化CO_(2)RR的动态演变过程提供了有利方法.本文总结了原位红外光谱在电催化CO_(2)RR研究中的应用:首先,简要介绍了电化学衰减全反射表面增强红外光谱的表面增强机制;详细探讨了原位衰减全反射表面增强红外光谱技术在研究原子级金属催化剂催化CO_(2)/CORR反应动态演变过程的关键作用;简述了原位红外谱图确定界面水的相关信息以及电极局部pH值的定量方法.原位电化学红外光谱技术加深了对CO_(2)RR反应机制的理解,揭示了催化剂结构、电解质种类、分子吸附方式等对反应活性和选择性的调控规律.尽管研究已取得较大进展,但由于电催化CO_(2)RR的复杂性,学者对该反应的认知仍不够全面和深入,面临的机遇和挑战如下:(1)精准辨识CO_(2)RR关键中间体/生成物.特别是当中间体/生成物的特征峰与其他峰重叠时,精准识别相关特征峰将极具挑战.一方面,需进一步提高原位光谱技术分辨率;另一方面,近年来深度学习算法在光谱分析领域的应用为中间体/生成物混合特征峰的精准识别提供了有效方案,此类算法能建立变量之间的关系,实现光谱中特征信息的智能、精准提取;(2)深入解析CO_(2)RR机理和复杂的反应路径.目前,研究者尚难以通过直接实验手段明确CO_(2)RR路径.原位电化学红外光谱技术结合密度泛函理论(DFT)是明确CO_(2)RR中间体和反应途径的可行方案,能够进一步指导反应条件优化和催化剂结构设计;(3)建立工况下的原位CO_(2)RR机理研究方案.膜电极组件(MEA)电解槽通过使用膜直接连接阴极气体扩散电极和阳极,有效解决了H型反应器的局限性,具有工业应用前景.然而,基于MEA的工况条件CO_(2)RR机制研究鲜有报道.因此,需要开发工况条件下的原位电化学光谱技术,以探究三相界面分子尺度关键中间体/生成物动态演变,并建立工况条件的CO_(2)RR催化构效关系,这将有助于提高工况下的选择性、转化效率,以及实现更高价值的多碳产品的规模生产,并进一步指导高效反应器设计.综上,本文详细综述了原位红外光谱在电化学CO_(2)RR研究中的应用,并对电催化CO_(2)RR目前遇到的问题提出了解决方案,希望对广大科研工作者利用原位红外光谱进一步深入研究电催化CO_(2)RR提供参考和借鉴. 展开更多
关键词 二氧化碳电还原 单原子催化剂 电化学原位衰减全反射表面增强红外光谱 反应动态演变过程 界面水
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红外光谱快速检测生物降解聚酯的研究
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作者 殷茂峰 王晓珂 +5 位作者 孙国华 张信 李鹏鹏 马劲松 肖军 侯连龙 《中国塑料》 CAS CSCD 北大核心 2024年第9期94-100,共7页
首先,利用衰减全反射红外光谱法采集常见生物降解塑料的红外光谱图,标记其特征官能团。随后,通过熔融共混和溶液共混得到了生物降解塑料和非降解塑料的共混物。结果表明,基于红外光谱的快速检测方法在生物降解塑料的分析中具有高效性和... 首先,利用衰减全反射红外光谱法采集常见生物降解塑料的红外光谱图,标记其特征官能团。随后,通过熔融共混和溶液共混得到了生物降解塑料和非降解塑料的共混物。结果表明,基于红外光谱的快速检测方法在生物降解塑料的分析中具有高效性和准确性,为推动生物降解塑料的发展以及对塑料污染的治理提供了有益的参考。 展开更多
关键词 生物降解塑料 红外光谱 衰减全反射 快速检测 共混
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傅里叶变换衰减全反射红外光谱检测血液样本在疾病筛查及诊断的应用进展
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作者 吴忻禹 张陆成 黎永青 《诊断学理论与实践》 2024年第3期335-340,共6页
傅里叶变换衰减全反射红外(attenuated total reflection Fourier transform infrared,ATR-FTIR)光谱技术以其快速、准确、无创的特点,在生物医学领域尤其是临床血液学检验中显示出巨大潜力。该技术记录样本中分子的振动光谱,提供生物... 傅里叶变换衰减全反射红外(attenuated total reflection Fourier transform infrared,ATR-FTIR)光谱技术以其快速、准确、无创的特点,在生物医学领域尤其是临床血液学检验中显示出巨大潜力。该技术记录样本中分子的振动光谱,提供生物样品内核酸、蛋白质和脂质的化学结构信息,可用于疾病筛查和诊断。ATR-FTIR光谱技术在地中海贫血、艾滋病毒感染、乳腺癌、卵巢癌和脑瘤等疾病中的研究现状和发展情况,提示该技术结合化学计量学方法可实现疾病的快速筛查、诊断与鉴别诊断。ATR-FTIR光谱技术与偏最小二乘法回归模型相结合,以定量法分析人外周血样品中平均红细胞血红蛋白含量、平均红细胞体积和血红蛋白等地中海贫血筛查指标,筛查地中海贫血的灵敏度、特异度分别达到100.0%和95.3%。采用ATR-FTIR光谱技术,基于遗传算法的线性判别分析法,分析血液样本红外图谱中1653 cm-1(酰胺Ⅰ带)、1558 cm-1(酰胺Ⅱ带)、1506 cm-1(环基)和901 cm-1(磷酸二酯伸缩带)处的特征峰,对人类免疫缺陷病毒(human immunodeficiency virus,HIV)感染孕妇血液样本的辨别准确率为89%,灵敏度、特异度分别为83%、92%。采用主成分回归(principal component regression)法对乳腺患者血液ATRFTIR光谱进行识别,其灵敏度与特异度高达92.3%与87.1%此外,ATR-FTIR光谱技术还可应用于生物医学领域的其他方面,如细胞和组织学样本的检测、疾病严重程度的分类等。ATR-FTIR光谱技术展现出广阔的应用前景,但仍面临环境干扰、样本污染等挑战。未来,随着ATR-FTIR光谱技术的优化、发展,其有望在更多疾病的临床血液学检验中发挥重要作用。 展开更多
关键词 红外光谱 傅里叶变换衰减全反射红外光谱 临床血液学
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比较教学法在红外光谱分析实验教学中的探索与应用
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作者 况婷 罗海健 +1 位作者 宋琳琳 柯丁宁 《实验科学与技术》 2024年第4期108-112,共5页
紧密结合实验特性和教学目的,提出将比较教学法应用于实验课堂,深入探讨了其在红外光谱分析实验教学中的应用与实践。通过实施这种教学方法,学生不仅能深入理解透射法与衰减全反射红外光谱分析法的异同点,而且能掌握这两种方法的实际应... 紧密结合实验特性和教学目的,提出将比较教学法应用于实验课堂,深入探讨了其在红外光谱分析实验教学中的应用与实践。通过实施这种教学方法,学生不仅能深入理解透射法与衰减全反射红外光谱分析法的异同点,而且能掌握这两种方法的实际应用技巧。实践表明,比较学习法有效推动了高分子材料分析实验的教学改革和质量的提升,有助于强化学生实践操作能力,激发他们的科研兴趣,为培养未来的科研人才奠定坚实基础。 展开更多
关键词 比较教学法 傅里叶变化红外光谱法 衰减全反射技术 高分子材料
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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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Quantification of TOC and TN in reservoir sediments using Fourier transform infrared spectroscopy 被引量:1
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作者 Lin Mei Yihong Yue +2 位作者 Yong Qin Xueping Chen Fushun Wang 《Soil Ecology Letters》 CAS 2022年第4期399-408,共10页
This study aims to quantitatively assess the total organic carbon(TOC)and total nitrogen(TN)content of reservoir sediments in southwest China using Fourier transform infrared spectroscopy(FTIRS).FTIRS measurements wer... This study aims to quantitatively assess the total organic carbon(TOC)and total nitrogen(TN)content of reservoir sediments in southwest China using Fourier transform infrared spectroscopy(FTIRS).FTIRS measurements were performed on 187 sediment samples from four reservoirs to develop calibration models that relate FTIR spectral information with conventional property concentrations using partial least squares regression(PLSR).Robust calibration models were established for TOC and TN content.The external validation of these models yielded a significant correlation between FTIR-inferred and conventionally measured concentrations of R^(2)=0.88 for TOC,R^(2)=0.90 for TN.This method can be performed with a small sample size and is non-destructive throughout the simple measurement process.The TOC and TN content in the sediment can be determined with high effectiveness without being overly expensive,making it an advantageous method when measuring a large number of samples. 展开更多
关键词 Fourier transform infrared spectroscopy CHEMOMETRICS total organic carbon total nitrogen Reservoir sediment
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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
Deliquescence and efflorescence are the two most important physicochemical processes of aerosol particles. In deliquescence and efflorescence cycles of aerosol particles, many fundamental problems need to be investiga... Deliquescence and efflorescence are the two most important physicochemical processes of aerosol particles. In deliquescence and efflorescence cycles of aerosol particles, many fundamental problems need to be investigated in detail on the molecular level, including ion and molecule interactions in supersaturated aerosols, metastable solid phases that may be formed, and microscopic structures and deliquescence mechanisms of aerosol particles. This paper presents a summary of the progress made in recent investigations of deliquescence and efflorescence processes of aerosol particles by four common spectral techniques, which are known as Raman/electrodynamic balance, Fourier transform infrared/aerosol flow tube, Fourier transform infrared/attenuated total reftection, and confocal Raman on a quartz substrate. 展开更多
关键词 AEROSOL DELIQUESCENCE EFFLORESCENCE Raman/electrodynamic balance Fourier transform infrared/aerosol flow tube Fourier transform infrared/attenuated total reflection Confocal Raman
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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 被引量:1
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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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烟叶总还原糖近红外光谱稳健模型的建立及其在多台仪器的长期应用 被引量:1
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作者 束茹欣 居雷 +4 位作者 吴圣超 倪力军 王文俊 栾绍嵘 张立国 《分析测试学报》 CAS CSCD 北大核心 2023年第11期1479-1487,共9页
该文使用基于光谱图像特征抽提的尺度不变特征变换(SIFT)的多步波长筛选方法建立了烟叶总还原糖(TRS)的近红外光谱(NIRS)稳健模型,实现了其在多台仪器的直接共享和长期应用。首先采用SIFT方法根据代表性主机样品光谱挑选特征光谱点集合... 该文使用基于光谱图像特征抽提的尺度不变特征变换(SIFT)的多步波长筛选方法建立了烟叶总还原糖(TRS)的近红外光谱(NIRS)稳健模型,实现了其在多台仪器的直接共享和长期应用。首先采用SIFT方法根据代表性主机样品光谱挑选特征光谱点集合Uc,然后从Uc中剔除样本光谱标准方差(SDSS)过低的点,挑选重要特征光谱点集合Uic,此两步波长筛选法简称为SIFT-SDSS。随后进一步从Uic中挑选对水分不敏感(Mois⁃ture-unsensitive,MUS)的波长点,得到重要且稳定的光谱点集合Uisc,此3步波长筛选法简称为SIFT-SDSSMUS。从2011~2013年采集的292个主机烟叶样品中按TRS浓度区间选择80%样品作为建模集,建立不同波长集合下烟叶TRS的偏最小二乘回归(PLSR)校正模型。结果表明,基于SIFT-SDSS两步波长筛选的光谱点建立的TRS模型传递到6台从机预测另外77个2011~2013年样品的TRS时,所有从机样品的平均相对误差绝对值(MARE)均小于6%,满足企业内控要求。该模型对5台近红外仪上2014~2020年各年度样品、1台近红外仪上2014~2019年各年度样品的MARE均小于6%。而全波长模型及SIFT波长筛选方法所建模型在7台仪器上对多个不同年份下样品中TRS的MARE大于6%,难以实现长期应用。SIFT-SDSS-MUS方法所建TRS模型变量最少,但其模型传递能力和长期应用能力略逊于SIFT-SDSS模型。SIFT-SDSS所建TRS模型稳健性好、可解释性强、运算速度快,可在7台同型号近红外仪上直接共享、在6台仪器上连续应用至少6年,大大减少了烟叶TRS近红外光谱模型维护及传递的工作量。 展开更多
关键词 多步波长筛选 近红外光谱模型传递 模型寿命 烟叶 总还原糖 尺度不变特征变换
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不同采收月份唐古特大黄多元红外光谱判别 被引量:1
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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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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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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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