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Infrared spectroscopic analysis of O-H bond dynamics in one-dimensional confined water and bulk water
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作者 ZHANG Lei WANG Tian-Qi FAN Yan-Ping 《红外与毫米波学报》 北大核心 2025年第1期78-85,共8页
In sub nanometer carbon nanotubes,water exhibits unique dynamic characteristics,and in the high-frequency region of the infrared spectrum,where the stretching vibrations of the internal oxygen-hydrogen(O-H)bonds are c... In sub nanometer carbon nanotubes,water exhibits unique dynamic characteristics,and in the high-frequency region of the infrared spectrum,where the stretching vibrations of the internal oxygen-hydrogen(O-H)bonds are closely related to the hydrogen bonds(H-bonds)network between water molecules.Therefore,it is crucial to analyze the relationship between these two aspects.In this paper,the infrared spectrum and motion characteristics of the stretching vibrations of the O-H bonds in one-dimensional confined water(1DCW)and bulk water(BW)in(6,6)single-walled carbon nanotubes(SWNT)are studied by molecular dynamics simulations.The results show that the stretching vibrations of the two O-H bonds in 1DCW exhibit different frequencies in the infrared spectrum,while the O-H bonds in BW display two identical main frequency peaks.Further analysis using the spring oscillator model reveals that the difference in the stretching amplitude of the O-H bonds is the main factor causing the change in vibration frequency,where an increase in stretching amplitude leads to a decrease in spring stiffness and,consequently,a lower vibration frequency.A more in-depth study found that the interaction of H-bonds between water molecules is the fundamental cause of the increased stretching amplitude and decreased vibration frequency of the O-H bonds.Finally,by analyzing the motion trajectory of the H atoms,the dynamic differences between 1DCW and BW are clearly revealed.These findings provide a new perspective for understanding the behavior of water molecules at the nanoscale and are of significant importance in advancing the development of infrared spectroscopy detection technology. 展开更多
关键词 one-dimensional confined water infrared spectroscopy hydrogen bonds
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Rapid Non-destructive Detection for Molds Colony of Paddy Rice Based on Near Infrared Spectroscopy 被引量:4
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作者 Zhang Qiang Liu Cheng-hai +4 位作者 Sun Jing-kun Cui Yi-juan Li Qun Jia Fu-guo Zheng Xian-zhe 《Journal of Northeast Agricultural University(English Edition)》 CAS 2014年第4期54-60,共7页
Near infrared spectrometer technology under a wavelength range of 918-1045 nm was used to rapidly detect paddy rice that was stored at 5℃, 15℃ and 25℃. A total of 121 paddy rice samples were collected from artifici... Near infrared spectrometer technology under a wavelength range of 918-1045 nm was used to rapidly detect paddy rice that was stored at 5℃, 15℃ and 25℃. A total of 121 paddy rice samples were collected from artificial infection with moulds to build the calibration models to calculate the total number colony of moulds based on the principal component regression method and multiple linear regression method. The results of statistical analysis indicated that multiple linear regression method was applicable to the detection of the total number colony of moulds. The correlation of calibration data set was 0.943. The correlation of prediction data set was 0.897. Therefore, the result showed that near infrared spectroscopy could be a useful instrumental method for determining the total number colony of moulds in paddy rice. The near infrared spectroscopy methodology could be applied for monitoring mould contamination in postharvest paddy rice during storage and might become a powerful tool for monitoring the safety of the grain. 展开更多
关键词 near infrared spectroscopy paddy rice MOULDS multiple linear regression principal component analysis
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Infrared Spectroscopy and Morphological Assessments on the Nutritional Value of Prickly Pear Fruit 被引量:1
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作者 Moamen SRefat Amnah MAlsuhaibani Mo hamed Nagaty 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2021年第2期648-653,共6页
The prickly pear fruit helps in combating viral based infections.It is used to treat diabetes and declared to possess hypoglycemic effects.There is also record of the usage of the fruit in the olden days as a remedy f... The prickly pear fruit helps in combating viral based infections.It is used to treat diabetes and declared to possess hypoglycemic effects.There is also record of the usage of the fruit in the olden days as a remedy for diabetes,lipid disorders,inflammation,ulcers,and pharmacologic side effects.The chemical composition and nutritional values of skin,flesh and seed of prickly pear fruit were investigated and discussed on a dry weight situation.The infrared spectra as well as scanning electron microscopy(SEM)techniques were used to identify the functional groups of carbohydrates,amino acids,and protein.The infrared spectral data of all three(skin,flesh,and seeds)species were recorded and assigned to the presence of distinguish peaks that referred to the three different sugars(glucose,fructose and saccharose)and cyclic aliphatic hydrocarbons moieties.On the other hand,the SEM is a powerful tool to investigate the morphological features of the components.SEM assays were examined on the surfaces of skin,flesh and seed branches showing a small particle that tends to form clusters with different shapes compared to each other.The Energy-dispersive X-ray spectroscopy(EDX)is an analytical technique used for the elemental analysis or chemical characterization of a sample.The EDX spectral technique of the skin,flesh and seeds were confirmed the presence of different essential and useful elements such as carbon,oxygen,magnesium,calcium,potassium,sulfur,aluminum,silicon,chloride,and phosphorus. 展开更多
关键词 infrared spectroscopy SEM EDX Prickly pear fruit SKIN FLESH SEED
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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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Study on the Hydrogen Bond Interaction Between Soy Protein Isolate and Glycerol Using Two-Dimensional Correlation Fourier-Transform Infrared Spectroscopy
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作者 YAN Zhi-wei YANG He-li ZHANG Pu-dun 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第S1期85-86,共2页
A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensi... A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensional(PCMW2D)and two-dimensional correlation(2DCOS)analyses were applied to the amideⅠband and thus the hydrogen bond interaction between SPI and Gly was systematically investigated.When Gly concentrations were in the range 0~35%,the hydrogen bond amongβ-sheets was replaced by the one between SPI chain and Gly molecule,which caused these protein chains being changed toα-helix.However,the transformation ofβ-sheet toα-helix was saturated and both of them tend to change to random coil when Gly concentrations were in the range 35%~60%. 展开更多
关键词 Two-dimensional correlation infrared spectroscopy Soy protein isolate GLYCEROL Hydrogen bond interaction
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Identification of Plant-Pathogenic Fungi Using Fourier Transform Infrared Spectroscopy Combined with Chemometric Analyses
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作者 CHAI A-li WANG Yi-kai +3 位作者 ZHU Fa-di SHI Yan-xia XIE Xue-wen LI Bao-ju 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第11期3764-3771,共8页
Identification of plant-pathogenic fungi is time-consuming due to cultivation and microscopic examination and can be influenced by the interpretation of the micro-morphological characters observed.The present investig... Identification of plant-pathogenic fungi is time-consuming due to cultivation and microscopic examination and can be influenced by the interpretation of the micro-morphological characters observed.The present investigation aimed to create a simple but sophisticated method for the identification of plant-pathogenic fungi by Fourier transform infrared(FTIR)spectroscopy.In this study,FTIR-attenuated total reflectance(ATR)spectroscopy was used in combination with chemometric analysis for identification of important pathogenic fungi of horticultural plants.Mixtures of mycelia and spores from 27fungal strains belonging to nine different families were collected from liquid PD or solid PDA media cultures and subjected to FTIR-ATR spectroscopy measurements.The FTIR-ATR spectra ranging from 4 000to 400cm-1 were obtained.To classify the FTIRATR spectra,cluster analysis was compared with canonical vitiate analysis(CVA)in the spectral regions of3 050~2 800and 1 800~900cm-1.Results showed that the identification accuracies achieved 97.53%and99.18%for the cluster analysis and CVA analysis,respectively,demonstrating the high potential of this technique for fungal strain identification. 展开更多
关键词 Fourier transform infrared spectroscopy(FTIR) Plant-pathogenic fungi IDENTIFICATION Cluster analysis Canonical vitiate analysis
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Determination of surface structure and the depth profile of silica glass by infrared spectroscopy
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作者 C. Z. Tan 《光学精密工程》 EI CAS CSCD 北大核心 2005年第4期413-420,共8页
The surface structure and properties are different from those of the bulk, depending on the substrate materials and deposition condition, and playing an important role in precise optical components. The conventional s... The surface structure and properties are different from those of the bulk, depending on the substrate materials and deposition condition, and playing an important role in precise optical components. The conventional spectroscopic methods to monitor the surface structure are restricted only in several layers of molecules. It is known that the penetration depth of the incident light increases with its wavelength and decreases with the angle of incidence. Thus infrared spectroscopy provides a powerful means for determination of surface structure and the depth profile up to micrometers. By recording the reflection spectra at different angles of incidence, the surface structure and its depth profile can be monitored successively. Further, the incident field has the subcomponents parallel and perpendicular to the surface, which excite the transverse and longitudinal optic modes, respectively. Change of the polarization direction of the incident light provides a practical function to study anisotropic property of the surface and the interaction between the transverse and longitudinal optic modes. In this work, infrared spectrophotometer was applied to investigate the depth profile in microstructure of silica glass. Combining with the glass fiber system, this technique can be used for in-situ control of the deposition process. In comparing with ellipsometry, this method reveals both structural and constitutional information. 展开更多
关键词 硅石 光谱 红外线 表面结构 光学材料
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Near-Infrared Imaging Using a High-Speed Monitoring Near Infrared Hyperspectral Camera(Compovision) 被引量:3
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作者 Daitaro Ishikawa Asako Motomura +1 位作者 Yoko Igarashi Yukihiro Ozaki 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2015年第4期865-869,共5页
This review paper reports near-infrared(NIR)imaging studies using a newly-developed NIR camera,Compovision.Compovision can measure a significantly wide area of 150mm×250mm at high speed of between 2and 5s.It enab... This review paper reports near-infrared(NIR)imaging studies using a newly-developed NIR camera,Compovision.Compovision can measure a significantly wide area of 150mm×250mm at high speed of between 2and 5s.It enables a wide spectral region measurement in the 1 000~2 350nm range at 6nm intervals.We investigated the potential of Compovision in the applications to industrial problems such as the evaluation of pharmaceutical tablets and polymers.Our studies have demonstrated that NIR imaging based on Compovision can solve several issues such as long acquisition times and relatively low sensitivity of detection.NIR imaging with Compovision is strongly expected to be applied not only to pharmaceutical tablet monitoring and polymer characterization but also to various applications such as those to food products,biomedical substances and organic and inorganic materials. 展开更多
关键词 Near infrared spectroscopy IMAGING Hyperspectral camera
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Fourier transform infrared spectral features of plant biomass components during cotton organ development and their biological implications 被引量:1
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作者 HE Zhongqi LIU Yongliang +2 位作者 KIM Hee Jin TEWOLDE Haile ZHANG Hailin 《Journal of Cotton Research》 2022年第2期130-142,共13页
Background:The majority of attenuated total reflection Fourier transform infrared(ATR FT-IR)investigations of cotton are focused on the fiber tissue for biological mechanisms and understanding of fiber development and... Background:The majority of attenuated total reflection Fourier transform infrared(ATR FT-IR)investigations of cotton are focused on the fiber tissue for biological mechanisms and understanding of fiber development and maturity,but rarely on other cotton biomass comp on ents.This work examined in detail the ATR FT-IR spectral features of various cott on tissues/organs at reproductive and maturation stages,an a lyzed and discussed their biological implications.Results:The ATR FT-IR spectra of these tissues/organs were an a lyzed and compared with the focus on the lower wavenumber fingerprinting range.Six outstanding FT-IR bands at 1730,1620,1525,1235,1050 and 895 cm^(-1) represented the major C=O stretching,protein Amide I,Amide II,the O-H/N-H deformation,the total C-O-C stretching and the β-glycosidic linkage in celluloses,respectively,and impacted differently between these organs with the two growth stages.Furthermore,the band intensity at 1620,1525,1235,and 1050 cm^(-1) were exclusively and significantly correlated to the levels of protein(Amide I bond),protein(Amide II bond),cellulose,and hemicellulose,respectively,whereas the band at 1730 cm^(-1) was negatively correlated with ash content.Conclusions:The resulting observations indicated the capability of ATR FT-IR spectroscopy for monitoring changes,transportation,and accumulation of the major chemical components in these tissues over the cotton growth period.In other words,this spectral technology could be an effective tool for physiological,biochemical,and morphological research related to cotton biology and development. 展开更多
关键词 COTTON Fourier transform infrared spectroscopy FIBER CELLULOSE PROTEIN Plant tissue
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Feasibility study of assessing cotton fiber maturity from near infrared hyperspectral imaging technique
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作者 LIU Yongliang TAO Feifei +1 位作者 YAO Haibo KINCAID Russell 《Journal of Cotton Research》 CAS 2023年第4期266-276,共11页
Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laborat... Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laboratories under a controlled environment.There is an increasing need to measure fiber maturity using low-cost(in general less than $20000)and small portable systems.In this study,a laboratory feasibility was performed to assess the ability of the shortwave infrared hyperspectral imaging(SWIR HSI)technique for determining the conditioned fiber maturity,and as a comparison,a bench-top commercial and expensive(in general greater than $60000)near infrared(NIR)instrument was used.Results Although SWIR HSI and NIR represent different measurement technologies,consistent spectral characteristics were observed between the two instruments when they were used to measure the maturity of the locule fiber samples in seed cotton and of the well-defined fiber samples,respectively.Partial least squares(PLS)models were established using different spectral preprocessing parameters to predict fiber maturity.The high prediction precision was observed by a lower root mean square error of prediction(RMSEP)(<0.046),higher R_(p)^(2)(>0.518),and greater percentage(97.0%)of samples within the 95% agreement range in the entire NIR region(1000-2500 nm)without the moisture band at 1940 nm.Conclusion SWIR HSI has a good potential for assessing cotton fiber maturity in a laboratory environment. 展开更多
关键词 Near infrared spectroscopy Near infrared hyperspectral imaging Fiber maturity Seed cotton Partial least squares regression
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Determination of manganese content in cottonseed meal using near-infrared spectrometry and multivariate calibration
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作者 YU En ZHAO Rubing +7 位作者 CAI Yunfei HUANG Jieqiong LI Cheng LI Cong MEI Lei BAO Lisheng CHEN Jinhong ZHU Shuijin 《Journal of Cotton Research》 2019年第2期105-111,共7页
Background:Manga nese(Mn)is an essential microelement in cotton seeds,which is usually determined by the techniques relied on hazardous reagents and complex pretreatment procedures.Therefore a rapid,low-cost,and reage... Background:Manga nese(Mn)is an essential microelement in cotton seeds,which is usually determined by the techniques relied on hazardous reagents and complex pretreatment procedures.Therefore a rapid,low-cost,and reagent-free analytical way is demanded to substitute the traditional analytical method.Results:The Mn content in cottonseed meal was investigated by near-infrared spectroscopy(NIRS)and chemometrics techniques.Standard normal variate(SNV)combined with first derivatives(FD)was the optimal spectra pre-treatment method.Monte Carlo uninformative variable elimination(MCUVE)and successive projections algorithm method(SPA)were employed to extract the informative variables from the full NIR spectra.The lin ear and non linear calibration models for cott on seed Mn content were developed.Finally,the optimal model for cottonseed Mn content was obtained by MCUVE-SPA-LSSVM,with root mean squares error of prediction(RMSEP)of 1.994 6,coefficient of determination(R^2)of 0.949 3,and the residual predictive deviation(RPD)of 4.370 5,respectively.Conclusions:The MCUVE-SPA-LSSVM model is accuracy enough to measure the Mn content in cottonseed meal,which can be used as an alter native way to substitute for traditional analytical method. 展开更多
关键词 COTTONSEED MEAL MANGANESE CONTENT NEAR-infrared spectroscopy MULTIVARIATE calibration
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基于近红外光谱技术快速定量检测香菇面制品中香菇含量的研究 被引量:6
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作者 弓志青 张永琥 +3 位作者 沈小刚 陆秀香 贾凤娟 王文亮 《中国果菜》 2025年第1期8-12,37,共6页
为定量检测香菇面制品中香菇含量,采用近红外光谱扫描添加0.5%~10%的香菇面粉样本,采用偏最小二乘法(PLS)建立含香菇面制品中香菇定量快速无损检测方法。取含香菇的面粉样本120余份,将96个样品作为定标集,24个作为验证集,进行10000 cm^(... 为定量检测香菇面制品中香菇含量,采用近红外光谱扫描添加0.5%~10%的香菇面粉样本,采用偏最小二乘法(PLS)建立含香菇面制品中香菇定量快速无损检测方法。取含香菇的面粉样本120余份,将96个样品作为定标集,24个作为验证集,进行10000 cm^(-1)~4000 cm^(-1)近红外全波长扫描,得到添加含香菇面粉的近红外原始光谱,通过Spectrum Quant软件,利用偏最小二乘法,将光谱预处理后与香菇含量建立近红外模型,并进行模型的验证与预测。结果表明,最优的预处理方法为MSC+平滑点2+二阶导数降噪2预处理,主因子数10,校正集方程与验证集方程的相关性良好(R2>99%),预测性较好(偏差<5%),模型有较好的准确度,为香菇面制品中香菇含量的检测提供了方法基础。 展开更多
关键词 近红外光谱 快速检测 香菇 面制品
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基于双路多尺度卷积的近红外光谱羊绒羊毛纤维预测模型 被引量:1
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作者 陈锦妮 田谷丰 +4 位作者 李云红 朱耀麟 陈鑫 门玉乐 魏小双 《光谱学与光谱分析》 北大核心 2025年第3期678-684,共7页
羊绒具有轻盈舒适、光滑柔软、稀释透气以及保暖好的特点,由于羊绒价格十分昂贵,因此市场上的羊绒产品质量良莠不齐。现有的显微镜法、DNA法、化学溶解法和基于图像的方法具有损坏样本、设备昂贵、主观性强等不足。近红外光谱技术是一... 羊绒具有轻盈舒适、光滑柔软、稀释透气以及保暖好的特点,由于羊绒价格十分昂贵,因此市场上的羊绒产品质量良莠不齐。现有的显微镜法、DNA法、化学溶解法和基于图像的方法具有损坏样本、设备昂贵、主观性强等不足。近红外光谱技术是一种非破坏性、可进行建模操作的快速测量方法。针对传统的建模方法通常无法学习出通用的近红外光谱波段特征,导致泛化能力弱,且羊绒羊毛纤维的近红外光谱波段特征相似,难以区分的问题,本文提出一种基于双路多尺度卷积的近红外光谱羊绒羊毛纤维预测模型。采集了羊绒羊毛样品的近红外光谱波段数据共1170个进行验证,近红外光谱波段数据范围是1300~2500 nm。利用两个并行卷积神经网络来提取近红外光谱波段的特征,采用原始近红外光谱波段数据和降维近红外光谱波段数据同时输入的方式,并利用多尺度特征提取模块进一步提取中间具有贡献力的近红外光谱波段特征,利用路径交流模块用于两路近红外光谱波段特征的信息交流,最后利用类级别融合得到羊绒羊毛纤维预测结果。在实验过程中,将采集的80%近红外光谱波段数据用于模型训练,20%近红外光谱波段数据用于模型测试。模型测试集的平均预测准确率为94.45%,与传统算法中的随机森林、SVM、1D-CNN等算法相比较分别提升了7.33%、5.22%、2.96%,并进行消融实验对所提模型的结构进一步验证。实验结果表明,本文提出的双路多尺度卷积的近红外光谱羊绒羊毛纤维预测模型可实现羊绒羊毛纤维的快速无损预测,为近红外光谱羊绒羊毛纤维预测提供了新的思路。 展开更多
关键词 羊绒羊毛 近红外光谱 深度学习 双路多尺度卷积神经网络
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基于改进一维卷积神经网络模型的蛋清粉近红外光谱真实性检测 被引量:1
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作者 祝志慧 李沃霖 +4 位作者 韩雨彤 金永涛 叶文杰 王巧华 马美湖 《食品科学》 北大核心 2025年第6期245-253,共9页
引入近红外光谱检测技术,构建改进一维卷积神经网络(one-dimensional convolutional neural network,1D-CNN)蛋清粉真实性检测模型。该模型基于1D-CNN模型,无需对光谱数据进行预处理;同时在网络中加入有效通道注意力模块和一维全局平均... 引入近红外光谱检测技术,构建改进一维卷积神经网络(one-dimensional convolutional neural network,1D-CNN)蛋清粉真实性检测模型。该模型基于1D-CNN模型,无需对光谱数据进行预处理;同时在网络中加入有效通道注意力模块和一维全局平均池化层,提高模型提取光谱特征的能力,减少噪声干扰。结果表明,改进后的EG-1D-CNN模型可判别蛋清粉样本的真伪,对于掺假蛋清粉的检测率可达到97.80%,总准确率(AAR)为98.93%,最低检测限(LLRC)在淀粉、大豆分离蛋白、三聚氰胺、尿素和甘氨酸5种单掺杂物质上分别可达到1%、5%、0.1%、1%、5%,在多掺杂中可达到0.1%~1%,平均检测时间(AATS)可达到0.004 4 s。与传统1D-CNN网络结构及其他改进算法相比,改进后的EG-1D-CNN模型在蛋清粉真实性检测上具有更高精度,检测速度快,且模型占用空间小,更适合部署在嵌入式设备中。该研究可为后续开发针对蛋粉质量检测的便携式近红外光谱检测仪提供一定的理论基础。 展开更多
关键词 蛋清粉 近红外光谱 真实性检测 一维卷积神经网络 深度学习
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功能性近红外光谱技术在注意缺陷多动障碍评估中应用的进展(综述) 被引量:1
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作者 杨杰 崔静静 胡珍玉 《中国心理卫生杂志》 北大核心 2025年第6期528-533,共6页
本文回顾了功能性近红外光谱技术(fNIRS)在注意缺陷多动障碍(ADHD)研究中的应用,分析了ADHD患者在任务态和静息态下的皮层激活异常,并探讨了fNIRS在ADHD诊断和治疗评估中的潜力,为未来ADHD研究和临床应用提供了新的方向和理论依据。
关键词 注意缺陷多动障碍 功能性近红外光谱技术 生物标志物 综述
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基于红外光谱技术对不同间隔年限栽培丹参土壤的红外光谱特征分析
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作者 乔璐 刘永红 +5 位作者 徐可可 余焕英 陈园杰 杨林林 董诚明 王磊 《光谱学与光谱分析》 北大核心 2025年第2期483-491,共9页
植物通过根际分泌物介导根际有益菌和病原菌差异性变化导致的连作障碍是制约丹参栽培发展的主要因素。提出一种基于红外光谱技术结合二维相关光谱的方法,快速检测丹参根际分泌物组成及含量变化。采集同一地区本底土(未种植丹参CK)、正... 植物通过根际分泌物介导根际有益菌和病原菌差异性变化导致的连作障碍是制约丹参栽培发展的主要因素。提出一种基于红外光谱技术结合二维相关光谱的方法,快速检测丹参根际分泌物组成及含量变化。采集同一地区本底土(未种植丹参CK)、正在种植丹参(19-ING)、丹参刚采收(19-ED、23-ED)、轮休1年(23-One)、轮休2年(23-Two)、轮休5年(19-Five)等7种丹参土壤样品的光谱,进行平滑降噪、一阶导数等,提取特征图谱,分析土壤化合物指纹图谱。不同间隔年限栽培丹参土壤的红外光谱峰位和峰形相同,主要差异波段在特征吸收峰3622、3380、1638、995、777、693、524和463 cm^(-1)附近,分别表征酚酸中酚羟基—OH、酯类和有机酸类中羰基C=O、亚甲基、苯环的吸收取代、环状酮类等物质的官能团,轮休1年的土壤在各个特征峰处吸光度增强,表明种植过程中酚酸类、酯类等自毒物质不断积累。不同茬次丹参种植土壤2维相关光谱在波段3750~3600、2170~2145、2060~2030和530~585 cm^(-1)处吸收峰的位置、个数、以及颜色都不相同,清晰地表征出官能团的差异。表明采用红外光谱和2D相关光谱相结合的方法能够实现土壤中有机化合物的快速检测和监测土壤化合物动态变化,为探索丹参连作障碍的形成机理及消减机制提供理论依据。 展开更多
关键词 丹参土壤 中红外光谱 二维红外光谱 酚酸类 酯类
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基于虚拟样本生成的集成模型提升过期药物光谱识别精度
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作者 谭超 谭成 +4 位作者 程斌 邹琴 陈慧 吴同 林瓒 《分析测试学报》 北大核心 2025年第6期1131-1138,共8页
基于近红外光谱定性识别假药需借助计算机和化学计量学从复杂、重叠、变动的光谱中提取特征信息和建立预测模型。在该类任务中,可能遇到某类样本相对不足的类别不平衡问题。基于生成虚拟样和集成建模,有望提升基于不平衡训练集上所得模... 基于近红外光谱定性识别假药需借助计算机和化学计量学从复杂、重叠、变动的光谱中提取特征信息和建立预测模型。在该类任务中,可能遇到某类样本相对不足的类别不平衡问题。基于生成虚拟样和集成建模,有望提升基于不平衡训练集上所得模型的识别精度。该文以阿奇霉素为研究对象,设计了一组实验样本集,采用基于虚拟样本技术的集成偏最小二乘判别分析模型构建了分类器,用于识别药物过期与否。在10个不同光谱区间上比较了单个模型和集成模型的性能,并讨论了不平衡比率、样本组成和集成规模的影响,集成分类器的灵敏度平均提高了约9%。通过实验确认了该集成策略的优势,在少数类样本过少时,所提出的集成算法更能显示出优势,该方法对其他类型体具有应用潜力。 展开更多
关键词 虚拟样本 集成 近红外光谱 药物 识别
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基于卷积神经网络组合算法的卷烟牌号在线分类识别研究
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作者 李石头 廖付 +8 位作者 吴继忠 张军 徐梦瑶 丁伟 李永生 李淑彪 何文苗 王辉 毕一鸣 《分析测试学报》 北大核心 2025年第3期514-520,共7页
为探究烟丝在线近红外光谱与卷烟牌号间的关系,提出了一种基于ResNeXt18-CNN-LightGBM混合模型的卷烟牌号分类识别方法。首先对采集的烟丝样本在线光谱数据进行预处理,并利用ResNeXt18网络模型对预处理后的光谱进行初次特征提取。然后... 为探究烟丝在线近红外光谱与卷烟牌号间的关系,提出了一种基于ResNeXt18-CNN-LightGBM混合模型的卷烟牌号分类识别方法。首先对采集的烟丝样本在线光谱数据进行预处理,并利用ResNeXt18网络模型对预处理后的光谱进行初次特征提取。然后将提取后的特征输入自定义的3层卷积神经(CNN)网络模型中,进行二次特征提取。最后将CNN提取的特征代入LightGBM分类器进行牌号分类训练。结果表明,ResNeXt18-CNN-LightGBM模型中烟丝牌号分类的准确率达97%。相较于传统的单个化学计量学算法,该文提出的基于卷积神经网络组合算法的卷烟牌号分类识别方法简单易行、准确性高、稳定性好,可应用于卷烟工业生产中卷烟牌号的在线识别,对卷烟品牌管理、生产质量评价及卷烟质量管控具有重要意义。 展开更多
关键词 在线近红外光谱 卷烟牌号 ResNeXt18 LightGBM 分类效果
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可可中可可脂含量近红外光谱模型构建及应用
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作者 伍宝朵 陈燕 +7 位作者 李煜 段良美 陈竹 王睿 白亭玉 吴桂苹 闫林 李付鹏 《中国粮油学报》 北大核心 2025年第5期191-196,共6页
可可脂是可可豆的重要品质指标,为了满足高可可脂可可品种的选育,实现可可豆中可可脂含量快速检测,本研究选取229份可可资源开展了近红外光谱分析,结合可可脂含量的化学值,利用偏最小二乘法及不同光谱预处理,构建了可可脂含量的近红外... 可可脂是可可豆的重要品质指标,为了满足高可可脂可可品种的选育,实现可可豆中可可脂含量快速检测,本研究选取229份可可资源开展了近红外光谱分析,结合可可脂含量的化学值,利用偏最小二乘法及不同光谱预处理,构建了可可脂含量的近红外光谱定标模型。建模结果表明,采用二阶导数(second derivative,SD)+标准正态变量变换(standard normal variate,SNV)对光谱进行预处理,光谱范围为4000~12000 cm-1,主因子数为10时,R 2(决定系数)最高为0.992,校正均方根误差为1.592,预测均方根误差为1.401,相对分析误差为7.731,模型表现最佳。外部验证结果显示,验证集的预测值和实测值具有显著相关性,单因素方差分析表明,实测值与预测值之间无显著差异(P=0.624)。利用新建模型对64份可可资源进行可可脂含量预测获得可可脂质量分数高于50%的资源4份,可可脂质量分数低于40%的资源4份。 展开更多
关键词 可可豆 可可脂 近红外光谱 模型 快速测定
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基于密度泛函理论的乳腺癌内分泌治疗药物的振动光谱研究
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作者 张川云 邓荣琴 +2 位作者 鲁建康 李伦 何建南 《分析科学学报》 北大核心 2025年第4期389-397,共9页
基于密度泛函理论(DFT)对两种乳腺癌内分泌治疗药物他莫昔芬片和来曲唑片的红外和拉曼光谱进行研究。首先采用DFT的B3LYP/6-31G(d,p)基组优化了他莫昔芬和来曲唑分子结构,计算出两种分子的理论红外和拉曼光谱,再与实验采集的他莫昔芬和... 基于密度泛函理论(DFT)对两种乳腺癌内分泌治疗药物他莫昔芬片和来曲唑片的红外和拉曼光谱进行研究。首先采用DFT的B3LYP/6-31G(d,p)基组优化了他莫昔芬和来曲唑分子结构,计算出两种分子的理论红外和拉曼光谱,再与实验采集的他莫昔芬和来曲唑纯品的红外和拉曼光谱进行对比分析,结果显示理论计算与实验采集的谱图吻合较好。其次,测试并分析了他莫昔芬片和来曲唑片的红外和拉曼光谱,发现两种药物的红外光谱主要为辅料乳糖的红外谱峰,而两种药物的拉曼光谱主要由其主要成分(他莫昔芬、来曲唑)与辅料乳糖的拉曼光谱组成,且他莫昔芬、来曲唑的拉曼特征峰明显。这些特征峰可成为进一步利用拉曼光谱对两种药物的主要成分进行定量分析的有效依据。上述研究结果可为发展DFT结合光谱技术在乳腺癌内分泌治疗药物快检方面的应用以及其质量监测新方法提供理论依据和技术参考。 展开更多
关键词 他莫昔芬 来曲唑 密度泛函理论 红外光谱 拉曼光谱
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