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Use of Fourier-transform infrared spectroscopy to rapidly diagnose gastric endoscopic biopsies 被引量:1
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作者 Qing-BoLi Xue-JunSun +5 位作者 Yi-ZhuangXu Li-MinYang Yuan-FuZhang Shi-FuWeng Jing-SenShi Jin-GuangWu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第25期3842-3845,共4页
AIM: To determine if Fourier-transform infrared (FT-IR)spectroscopy of endoscopic biopsies could accurately diagnose gastritis and malignancy.METHODS: A total of 123 gastroscopic samples, including 11 cases of cancero... AIM: To determine if Fourier-transform infrared (FT-IR)spectroscopy of endoscopic biopsies could accurately diagnose gastritis and malignancy.METHODS: A total of 123 gastroscopic samples, including 11 cases of cancerous tissues, 63 cases of chronic atrophic gastritis tissues, 47 cases of chronic superficial gastritis tissues and 2 cases of normal tissues, were obtained from the First Hospital of Xi'an Jiaotong University, China. A modified attenuated total reflectance (ATR) accessory was linked to a WQD-500 FT-IR spectrometer for spectral measurement followed by submission of the samples for pathologic analysis. The spectral characteristics for different types of gastroscopic tissues were summarized and correlated with the corresponding pathologic results.RESULTS: Distinct differences were observed in the FTIR spectra of normal, atrophic gastritis, superficial gastritis and malignant gastric tissues. The sensitivity of FT-IR for detection of gastric cancer, chronic atrophic gastritis and superficial gastritis was 90.9%, 82.5%, 91.5%, and specificity was 97.3%, 91.7%, 89.5% respectively.CONCLUSION: FT-IR spectroscopy can distinguish gastric inflammation from malignancy. 展开更多
关键词 fourier-transform infrared spectroscopy Gastric endoscope Gastric cancer Chronic gastritis Spectral analysis infrared detection
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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 active sites for hydrogenation over Ru/SBA-15 using in situ Fourier-transform infrared spectroscopy
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作者 Hangjia Shen Xianyuan Wu +2 位作者 Dahao Jiang Xiaonian Li Jun Ni 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第9期1597-1602,共6页
The active sites for hydrogenation over Ru/SBA‐15catalysts were identified using in situ Fourier‐transform infrared spectroscopy.The amount of active sites was proportional to the interfacial circumference of the Ru... The active sites for hydrogenation over Ru/SBA‐15catalysts were identified using in situ Fourier‐transform infrared spectroscopy.The amount of active sites was proportional to the interfacial circumference of the Ru particles.In contrast,the rate of hydrogen spillover from Ru to the support was inversely proportional to the size of the Ru metal particles.Consequently,a catalyst with small Ru metal particles has a high rate of hydrogen spillover but a low density of active sites,whereas one with large Ru particles has a low rate of hydrogen spillover but a high density of active sites.The formation of these active sites is probably an intermediate step in hydrogen spillover. 展开更多
关键词 Ru/SBA‐15 catalyst In‐situ Fourier‐transform infrared spectroscopy HYDROGENATION Active site Hydrogen spillover
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The evolving role of Fourier-transform midinfrared spectroscopy in genetic improvement of dairy cattle 被引量:3
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作者 K.M.Tiplady T.J.Lopdell +1 位作者 M.D.Littlejohn D.J.Garrick 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第3期626-638,共13页
Over the last 100 years,significant advances have been made in the characterisation of milk composition for dairy cattle improvement programs.Technological progress has enabled a shift from labour intensive,on-farm co... Over the last 100 years,significant advances have been made in the characterisation of milk composition for dairy cattle improvement programs.Technological progress has enabled a shift from labour intensive,on-farm collection and processing of samples that assess yield and fat levels in milk,to large-scale processing of samples through centralised laboratories,with the scope extended to include quantification of other traits.Fourier-transform midinfrared(FT-MIR)spectroscopy has had a significant role in the transformation of milk composition phenotyping,with spectral-based predictions of major milk components already being widely used in milk payment and animal evaluation systems globally.Increasingly,there is interest in analysing the individual FT-MIR wavenumbers,and in utilising the FT-MIR data to predict other novel traits of importance to breeding programs.This includes traits related to the nutritional value of milk,the processability of milk into products such as cheese,and traits relevant to animal health and the environment.The ability to successfully incorporate these traits into breeding programs is dependent on the heritability of the FT-MIR predicted traits,and the genetic correlations between the FT-MIR predicted and actual trait values.Linking FT-MIR predicted traits to the underlying mutations responsible for their variation can be difficult because the phenotypic expression of these traits are a function of a diverse range of molecular and biological mechanisms that can obscure their genetic basis.The individual FT-MIR wavenumbers give insights into the chemical composition of milk and provide an additional layer of granularity that may assist with establishing causal links between the genome and observed phenotypes.Additionally,there are other molecular phenotypes such as those related to the metabolome,chromatin accessibility,and RNA editing that could improve our understanding of the underlying biological systems controlling traits of interest.Here we review topics of importance to phenotyping and genetic applications of FT-MIR spectra datasets,and discuss opportunities for consolidating FT-MIR datasets with other genomic and molecular data sources to improve future dairy cattle breeding programs. 展开更多
关键词 Bovine milk Cattle breeding genetics fourier-transform infrared spectroscopy Trait prediction
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An economical and flexible chip using surface-enhanced infrared absorption spectroscopy for pharmaceutical detection:Combining qualitative analysis and quantitative detection 被引量:1
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作者 Jikai Wang Pengfei Zeng +3 位作者 Haitao Xie Suisui He Xilin Xiao Cuiyun Yu 《Journal of Pharmaceutical Analysis》 2025年第2期474-476,共3页
Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challeng... Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challenge emerges from the misalignment between the mid-IR light wavelength range and molecular dimensions,culminating in a constrained absorption cross-section and diminished vibrational absorption coefficients(Supplementary data). 展开更多
关键词 pharmaceutical detection quantitative detection structural analysis surface enhanced infrared absorption spectroscopy qualitative analysis chemical signatures infrared spectroscopy molecular vibrational spectroscopyfurnishes
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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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Oxidative Degradation of Plastic Bottle Tops in an Arid, Terrestrial Environment—Identifying Oxidative Degradation by Infrared Spectroscopy
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作者 Mahra Al Kaabi Vijo Poulose Thies Thiemann 《Journal of Environmental Protection》 2025年第2期66-86,共21页
This communication looks at the photo-oxidation of polythene and polypropylene plastic bottle tops that are placed on soil in a hot arid environment. The degree of oxidation of the plastic is monitored by FT-IR spectr... This communication looks at the photo-oxidation of polythene and polypropylene plastic bottle tops that are placed on soil in a hot arid environment. The degree of oxidation of the plastic is monitored by FT-IR spectroscopy. It is noted that while different bottle top types photo-oxidize at different rates, all show an appreciable level of oxidation after half a year of exposure to the environment. The oxidation leads to brittleness of the plastic, which leads to fissure formation in bottle tops of little thickness. This leads to fragmentation of the material upon impact, making plastic bottle tops an appreciable source of microplastics. 展开更多
关键词 PLASTICS Polythene POLYPROPYLENE Plastic Bottle Tops FRAGMENTATION Microplastics infrared spectroscopy Oxidation Index
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Determination of the kidney stone composition using infrared spectroscopy in Iran at a national referral center during 2019-2023
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作者 Abbas Basiri Azin Tahvildari +2 位作者 Mohammad Naji Pardis Ziaeefar Amir H.Kashi 《Asian Journal of Urology》 2025年第1期72-78,共7页
Objective The national lifetime prevalence of urolithiasis is estimated at 6.6%in Iran.However,reports on the composition of kidney stones have been based on imprecise methods like the chemical analysis.No prior large... Objective The national lifetime prevalence of urolithiasis is estimated at 6.6%in Iran.However,reports on the composition of kidney stones have been based on imprecise methods like the chemical analysis.No prior large-scale study has reported the composition of kidney stones based on the gold-standard methods(X-ray diffraction or infrared spectroscopy)in Iran.This study aimed to provide the composition of kidney stones based on Fourier transform infrared spectroscopy.Methods This is a cross-sectional study assessing urinary stone composition from various cities in Iran at a referral center using infrared spectroscopy from February 2019 to March 2023.Results This study determined the stone composition of 1092 patients from 10 cities in Iran.Overall,the majority of stones were composed of calcium oxalate(n=498;45.6%)and uric acid(UA,n=488;44.7%)followed by cystine(n=49;4.5%)and struvite(n=28;2.6%).Stone composition in Shiraz and Isfahan was roughly similar with a higher percentage of UA stones(53.4%and 53.6%,respectively)while the capital city of Iran(Tehran)had less frequent UA stones(39.9%)with a higher percentage of calcium oxalate stones.The percentage of UA stones increased with age as it was 11.1%in children,42.7%in adults,and 83.3%in geriatric patients(p<0.001).About 29.6%of cystine stones were observed in children.Conclusion The most frequent stone composition among kidney stones in Iran was calcium oxalate and UA stones.This relative frequency of UA stones is considerably higher than many international reports from neighboring as well as distant countries.More cystine stones were observed in children and women.Geriatric patients’stones were mostly composed of UA. 展开更多
关键词 Kidney stone UROLITHIASIS infrared spectroscopy Stone composition
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Revealing the difference of Stark tuning rate between interface and bulk by surface-enhanced infrared absorption spectroscopy
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作者 Manyu Zhu Fei Liang +4 位作者 Lie Wu Zihao Li Chen Wang Shule Liu Xiue Jiang 《Chinese Chemical Letters》 2025年第2期433-436,共4页
Revealing the factors that affect the vibrational frequency of Stark probe at interface is a pre-requirement for evaluating the absolute interfacial electric field.Here using surface-enhanced infrared absorption(SEIRA... Revealing the factors that affect the vibrational frequency of Stark probe at interface is a pre-requirement for evaluating the absolute interfacial electric field.Here using surface-enhanced infrared absorption(SEIRA)spectroscopy,attenuated total reflection(ATR)spectroscopy and molecular dynamics(MD),we reveal the assembled C≡N at gold nanofilm exhibits a reduced Stark tuning rate(STR)referring to the vibrational frequency shift in response to electric field comparing with the bulk which was regulated by the electron transfer between S and Au.These findings lead to a deeper understanding of the vibrational Stark effect at the interface and provide guidance for improving the interface electric field theory. 展开更多
关键词 Surface-enhanced infrared spectroscopy Attenuated total reflection spectroscopy Vibrational stark effect Stark tuning rate Cyano group
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Identification of Blueberry Producing Areas Based on CNN-SE and Near Infrared Spectroscopy
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作者 Guannan WANG Shanshan TANG Na WANG 《Agricultural Biotechnology》 2025年第1期57-61,共5页
[Objectives]This study was conducted to realize the rapid and nondestructive identification of blueberry producing areas and protect benefits of high-quality blueberry brands.[Methods]Five types of blueberries from di... [Objectives]This study was conducted to realize the rapid and nondestructive identification of blueberry producing areas and protect benefits of high-quality blueberry brands.[Methods]Five types of blueberries from different regions were selected as experimental subjects,and spectral analysis techniques were combined with deep learning.Firstly,standard normal variable transform(SNV)and convolutional smoothing(SG)were used to deal with scattering noise and other issues in original spectral data.Secondly,due to a large amount of redundant information and high correlation between adjacent wavelengths in the collected spectra,continuous projection algorithm(SPA)and partial least squares regression(PLS)were combined for screening of features with RMSE as the indicator,and 40 feature variables were obtained.Finally,a convolutional network model CNN-SE integrating a Squeeze and Excitation(SE)attention mechanism module was constructed and compared with convolutional neural network(CNN),support vector machine(SVM),and BP neural network.[Results]The CNN-SE model had the best effect,with the accuracy and precision of the test set reaching 95%and 94.56%,respectively,and the recall and F 1 score reaching 93.94%and 94.24%,respectively.[Conclusions]The CNN-SE convolution network model can realize rapid,nondestructive and high-throughout identification of blueberry producing areas. 展开更多
关键词 Near infrared spectroscopy technology BLUEBERRY Deep learning Origin identification
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Functional Near-Infrared Spectroscopy Study on Cortical Reorganisation Induced by Warm Acupuncture and Rehabilitation Training in Patients with Spastic Hemiplegia
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作者 Song Xu Du Qingzhou +3 位作者 Wang Juan Yang Hongbin Huang Jieying Guan Yanfu 《Science International Innovative Medicine》 2025年第1期70-75,共6页
The recovery of motor function in spastic hemiplegia following stroke is closely associated with cortical reorganisation.This study aimed to investigate the effects of warm acupuncture combined with rehabilitation tra... The recovery of motor function in spastic hemiplegia following stroke is closely associated with cortical reorganisation.This study aimed to investigate the effects of warm acupuncture combined with rehabilitation training on cortical activity and upper limb function using functional near-infrared spectroscopy.Ninety patients were randomly assigned to a warm acupuncture group,a rehabilitation training group,or a combined intervention group.After four weeks of intervention,clinical scores and changes in oxyhaemoglobin concentration in the affected motor cortex were assessed.Results demonstrated that the combined intervention group showed significantly greater improvement in Fugl-Meyer scores,reduced muscle tone,and enhanced activation in the affected primary motor cortex compared to the single intervention groups.Furthermore,functional improvement was significantly correlated with cortical activation changes.These findings indicate a synergistic effect between warm acupuncture and rehabilitation training,potentially mediated through promoting functional reorganisation of the affected cerebral cortex.This provides neuroimaging evidence supporting integrated Chinese and Western medicine rehabilitation protocols. 展开更多
关键词 Spastic hemiplegia Warm acupuncture Rehabilitation training Functional near infrared spectroscopy Brain plasticity
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Calculation of the carrier dynamics and impedance spectroscopy model in quantum well infrared photodetectors
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作者 Chenzhe Hu Yuyu Bu +2 位作者 Xianying Dai Fengqiu Jiang Yue Hao 《Journal of Semiconductors》 2025年第3期89-95,共7页
Quantum well infrared photodetectors(QWIPs) based on intersubband transitions hold significant potential for high bandwidth operation. In this work, we establish a carrier transport optimization model incorporating el... Quantum well infrared photodetectors(QWIPs) based on intersubband transitions hold significant potential for high bandwidth operation. In this work, we establish a carrier transport optimization model incorporating electron injection at the emitter to investigate the carrier dynamics time and impedance spectroscopy in GaAs/AlGaAs QWIPs. Our findings provide novel evidence that the escape time of electrons is the key limiting factor for the 3-dB bandwidth of QWIPs. Moreover, to characterize the impact of carrier dynamics time and non-equilibrium space charge region on impedance, we developed an equivalent circuit model where depletion region resistance and capacitance are employed to describe non-equilibrium space charge region. Using this model, we discovered that under illumination, both net charge accumulation caused by variations in carrier dynamics times within quantum wells and changes in width of non-equilibrium space charge region exert different dominant influences on depletion region capacitance at various doping concentrations. 展开更多
关键词 quantum well infrared photodetectors(QWIPs) carrier dynamics time impedance spectroscopy equivalent circuit model 3-dB bandwidth
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Analysis of Protein Content in Panicum miliaceum L. Using Near Infrared Transmittance Spectroscopy 被引量:2
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作者 牛宇 蒙秋霞 +5 位作者 张丽珍 赵婷婷 乔治军 牛伟 刘根科 冯耐红 《Agricultural Science & Technology》 CAS 2012年第5期965-968,共4页
[Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy (NITS) was used to build the mathematical mo... [Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy (NITS) was used to build the mathematical models for the quantitative analy- sis of protein content in the grains. Four combinations of treatment that first derivative and second derivative were respectively combined with partial least squares (PLS) and modified partial least squares (MPLS) were set to compare their effects on the original transmission spectrum. [Result] The predicting effects of the 4 combinations were similar. The optimal combination was first derivative with MPLS, in which the average determination coefficient of validation (RSQ) was 0.880 6, correlation coeffi- cient of cross validation (1-VR) was 0.857 0, standard error of calibration (SEC) was 0.342 4, standard error of cross validation (SECV) was 0.375 1, and the standard er- ror of prediction (SEP) was 0.454. [Conclusion] The constructed NITS model is a rapid way for the determination of protein content in grains of P. miliaceum. 展开更多
关键词 Near infrared transmittance spectroscopy Panicum miliaceum L. PROTEIN Calibration model
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Determination of Melamine by Infrared Spectroscopy Based on Nonlinear Modeling 被引量:1
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作者 张恒 高曼侠 +2 位作者 许兆棠 李文谦 王琪 《Agricultural Science & Technology》 CAS 2010年第8期133-136,共4页
[Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According... [Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According to dynamics,mathematical modeling and optimization theory,linear and nonlinear models were respectively set up by taking an absorption peak of 1 550 cm-1 as characteristic absorption peak. [Result] The correlation coefficient of nonlinear model was 0.922 7 and the recovery was 96%,which showed that the nonlinear model was more accurate than linearity model with correlation coefficient of 0.904 9 and recovery of 557%. [Conclusion] It is feasible to determine melamine content by using the nonlinear model quantitatively. 展开更多
关键词 infrared spectroscopy Quantitative analysis Nonlinear model MELAMINE
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Study on Methanol Oxidation at Pt and PtRu Electrodes by Combining in situ Infrared Spectroscopy and Differential Electrochemical Mass Spectrometry 被引量:1
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作者 陶骞 陈微 +2 位作者 姚瑶 Ammar Bin Yousaf 陈艳霞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第5期541-547,I0003,共8页
Methanol oxidation reaction (MOR) at Pt and Pt electrode surface deposited with various amounts of Ru (denoted as PtxRuy, nominal coverage y is 0.17, 0.27, and 0.44 ML) in 0.1 mol/L HClO4+0.5 mol/L MeOH has been ... Methanol oxidation reaction (MOR) at Pt and Pt electrode surface deposited with various amounts of Ru (denoted as PtxRuy, nominal coverage y is 0.17, 0.27, and 0.44 ML) in 0.1 mol/L HClO4+0.5 mol/L MeOH has been studied under potentiostatic conditions by in situ FTIR spectroscopy in attenuated-total-reflection con guration and di erential electro-chemical mass spectrometry under controlled flow conditions. Results reveal that (i) CO is the only methanol-related adsorbate observed by IR spectroscopy at all the Pt and PtRu electrodes examined at potentials from 0.3 V to 0.6 V (vs. RHE); (ii) at Pt0.56Ru0.44, two IR bands, one from CO adsorbed at Ru islands and the other from COL at Pt substrate are detected, while at other electrodes, only a single band for COL adsorbed at Pt is observed; (iii) MOR activity decreases in the order of Pt0.73Ru0.27〉Pt0.56Ru0.44〉Pt0.83Ru0.17〉Pt; (iv) at 0.5 V, MOR at Pt0.73Ru0.27 reaches a current e ciency of 50% for CO2 production, the turn-over frequency from CH3OH to CO2 is ca. 0.1 molecule/(site sec). Suggestions for further improving of PtRu catalysts for MOR are provided. 展开更多
关键词 Differential electrochemical mass spectrometry Electrochemical in situ infrared spectroscopy Methanol oxidation PtRu electrode Current efficiency
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Detection of Broad Bean Diseases by Fourier Transform Infrared Spectroscopy Combined with Curve Fitting 被引量:1
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作者 汪小华 刘刚 +4 位作者 欧全宏 周湘萍 郝建明 刘剑虹 汪禄祥 《Agricultural Science & Technology》 CAS 2015年第6期1310-1313,共4页
Fourier transform infrared (FTIR) spectroscopy was used to study diseased leaves in broad bean. Results showed that the infrared spectra of different broad bean diseased leaves were similar, which were mainly made u... Fourier transform infrared (FTIR) spectroscopy was used to study diseased leaves in broad bean. Results showed that the infrared spectra of different broad bean diseased leaves were similar, which were mainly made up of the vibrational absorption bands of protein,lipid and polysaccharide.There were minor differences in-cluding the spectral peak position, peak shape and the absorption intensity in the range of 1 800-1 300 cm-1. There were obvious differences among their second derivative spectra in the range of 1 800-1 300 cm-1. After the procedure of the Fourier self-deconvolution and curve fitting of health bean leaves and broad bean diseased leaves in the range of 1 700-1 500 cm-1, three sub-peaks were obtained at 1 550 cm-1 (protein amide Ⅱ band), 1 605 cm-1 (lignin) and 1 650 cm-1 (protein amide I band).The ratios of relative areas of the bands of amide Ⅱ, lignin, and amide I were 38.86%, 28.68% and 32.47% in the spectra of healthy leaves, respec-tively. It was distinguished from the diseased leaves (chocolate spot leaf: 15.42%, 42.98% and 41.61%, ring spot leaf:32.39%, 35.63% and 31.98%, rust leaf: 13.97%, 46.40% and 39.65%, yel owing leaf curl disease leaf: 24.01%,36.55% and 39.44%). For sub-peak area ratios (A1 563/A1 605, A1 650/A1 605 and A1 563/A1 654), those of four kinds of diseased leaves were smal er than that of healthy leaves, and there were also differences among four kinds of diseased leaves. The results proved that FTIR combining with curve fitting might be a potential y useful tool for detecting different kinds of broad bean diseases. 展开更多
关键词 Fourier transform infrared (FTIR) spectroscopy Broad bean diseases Second derivative spectra Curve fitting
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Rapid Detection on Quinoa Fiber Based on Near Infrared Spectroscopy
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作者 曹晓宁 田翔 +5 位作者 王君杰 刘思辰 穆志新 陆平 陶梅 乔治军 《Agricultural Science & Technology》 CAS 2016年第10期2383-2385,2422,共4页
[Objective] To explore a rapid determination method for fiber content in grains of quinoa. [Method] Near infrared spectra of 100 quinoa samples were collected. The predicted models for quantitative analysis of fiber c... [Objective] To explore a rapid determination method for fiber content in grains of quinoa. [Method] Near infrared spectra of 100 quinoa samples were collected. The predicted models for quantitative analysis of fiber contents in the grains were built using near infrared transmittance spectroscopy (NITS). [Result] In the wavelength range of 10 000-4 000 cm-1, the near infrared quantitative model of quinoa crude fiber was set up via first derivative + vector normalization preprocessing and combining with the data from chemical methods. The calibration and prediction effect were best, and then the cross validation determination coefficient (FFcv) and external validation determination coefficient (FFval) of fiber by near in- frared quantitative model were 0.884 8 and 0.876 1, respectively. [Conclusion] the model of NITS about complete grains quinoa fiber can be available for fast detecting quinoa fiber content. 展开更多
关键词 Chenopodium quinoa Willd FIBER Near infrared spectroscopy
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The Study of Using Near-infrared Diffuse Reflectance Spectroscopy Rapid Identify Wheat Drought Resistance-Ⅱ 被引量:3
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作者 吴少辉 冯伟森 +5 位作者 谷运红 焦珍 张学品 杨洪强 王卫东 张灿军 《Agricultural Science & Technology》 CAS 2013年第10期1507-1512,共6页
[Objective] The aim was to build an evaluation method rapidly identifying wheat drought tolerance with near infrared diffuse reflectance spectroscopy. [Method] In the research, 36 wheat varieties in 2007-2009 were cho... [Objective] The aim was to build an evaluation method rapidly identifying wheat drought tolerance with near infrared diffuse reflectance spectroscopy. [Method] In the research, 36 wheat varieties in 2007-2009 were chosen and drought-tolerance degrees of wheat were graded and identified according to Winter-wheat Drought Tol- erance Evaluation Technical Standards (GB/T 21127-2007), and harvest wheat grains underwent spectrum collection, with a full-spectrum analyzer, to establish a database. [Result] Based on qualitative analysis and full-spectrum correlation research, the coef- ficient of determination (RSQ) and cross-validation coefficient of determination (1-VR) were concluded at 0.697 5 and 0.600 2, showing near-infrared diffuse reflectance spectroscopy is of significant differences among wheat varieties and of significant or extremely significant correlation with drought-tolerance indices. [Conclusion] The re- search indicates that to evaluate drought-tolerance of wheat with near-infrared diffuse reflectance spectroscopy is a rapid and feasible way, which is simple, convenient without damages on grains, and of practical values for construction wheat drought-tol- erance evaluation index system and identification of breeding materials. 展开更多
关键词 Near infrared diffuse reflectance spectroscopy of wheat drought resis- tance screening index
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Recognition of wood surface defects with near infrared spectroscopy and machine vision 被引量:20
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作者 Huiling Yu Yuliang Liang +1 位作者 Hao Liang Yizhuo Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2379-2386,共8页
To improve the accuracy in recognizing defects on wood surfaces,a method fusing near infrared spectroscopy(NIR)and machine vision was examined.Larix gmelinii was selected as the raw material,and the experiments focuse... To improve the accuracy in recognizing defects on wood surfaces,a method fusing near infrared spectroscopy(NIR)and machine vision was examined.Larix gmelinii was selected as the raw material,and the experiments focused on the ability of the model to sort defects into four types:live knots,dead knots,pinholes,and cracks.Sample images were taken using an industrial camera,and a morphological algorithm was applied to locate the position of the defects.A portable near infrared spectrometer(900–1800 nm)collected the spectra of these positions.In addition,principal component analysis was utilized on these variables from spectral information and principal component vectors were extracted as the inputs of the model.The results show that a back propagation neural network model exhibited better discrimination accuracy of 92.7%for the training set and 92.0%for the test set.The research reveals that the NIR fusing machine vision is a feasible tool for detecting defects on board surfaces. 展开更多
关键词 WOOD BOARD surface DEFECTS Near infrared spectroscopy Machine VISION Accuracy of RECOGNITION
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Infrared Spectroscopic Study of Fistular Onion (Allium fistulosum) and Garlic (Allium sativum) Rust Leaves
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作者 何志遥 刘海丽 +4 位作者 吴秋娟 周湘萍 刘刚 董勤 俞帆 《Plant Diseases and Pests》 CAS 2011年第4期21-23,共3页
[ Objective] Fourier transform infrared spectroscopy was used to study fistular onion (Alliumfistulosum) and garlic (Allium sativum) rust leaves, so as to explore the application potential of mid-infrared spectros... [ Objective] Fourier transform infrared spectroscopy was used to study fistular onion (Alliumfistulosum) and garlic (Allium sativum) rust leaves, so as to explore the application potential of mid-infrared spectroscopy in the diagnosis of crop disease. [ Method] The normal green leaves and rust leaves of fistular onion and garlic were tested using fourier transform infrared spectroscopy, and their spectral differences were analyzed. [ Result] The infrared spectra of green leaves of fistular onion and garlic are mainly composed of the vibrational bands of polysaccharides, protein and ester. Normal and rust leaves exhibited differences in the fin- gerprint interval of 1 800 -900 cm-1 , in which the band at 1 640 cm-1 in the spectrum of flstular onion rust leaf became stronger, and the band at 1 103 cm-1 was not obvious compared with the spectrum of normal leaf. The absorbance ratios A1640/A1063, A1640/A1736, A1640/A2924, and A1063/A2924 of onion rust leaf were larger than the corresponding ratios A1638/A1 059, A1738/A1 38, A2921/A1638, and A2 92l/A1059 in the spectrum of normal leaf. The band of polysaccharides at 1 056 cm-1 in the spectrmn of garlic normal leaf was the strongest in fingerprint area, while the band at 1 634 cm-1 in the spectrum of garlic rust leaf was the strongest in that are- a. The absorbance ratios A1634/A1069 , A1634/A1099 , A1409/A2923 , and A1634/A737 of garlic rust leaf were larger than the corresponding ratios A1627/A1056 , A1623/A1104 , A1411/A2920 and A1627/A1740 of normal leaves. While the ratios A1634/A2923, A1059/A2923, and A1737/A2923 of garlic rust leaf were less than the corresponding values of A1627/A2920, A1056/A2920, and A1 740/A2920 of normal leaf. [ Conclusion] Rust leaf and normal leaf could be distinguished according to the differences in infrared spectra, and infrared spectroscopy could be developed as the detection method for crop diseases. 展开更多
关键词 Fistular Onion leaf Garlic leaf Rust disease Fourier transform infrared spectroscopy China
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