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Near Infrared Spectroscopy (NIRS) Model-Based Prediction for Protein Content in Cowpea
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作者 Kavera Biradar Waltram Ravelombola +1 位作者 Aurora Manley Caroline Ruhl 《American Journal of Plant Sciences》 CAS 2024年第3期145-160,共16页
Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models... Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models to estimate protein content in cowpea. A total of 116 cowpea breeding lines with a wide range of protein contents (19.28 % to 32.04%) were selected to build the model using whole seed and ground seed samples. Partial least-squares discriminant analysis (PLS-DA) regression technique with different pre-treatments (derivatives, standard normal variate, and multiplicative scatter correction) were carried out to develop the protein prediction model. Results showed: 1) spectral plots of both the whole seed and ground seed showed higher spectral scatter at higher wavelengths (>1450 nm), 2) data pre-processing affects prediction accuracy for bot whole seed and ground seed samples, 3) prediction using ground seed samples (0.64 R<sup>2</sup> 0.85) is better than the whole seed (0.33 R<sup>2</sup> 0.78), and 4) the data pre-processing second derivative with standard normal variate has the best prediction (R<sup>2</sup>_whole seed = 0.78, R<sup>2</sup>_ground seed = 0.85). The results will be of interest in cowpea breeding programs aimed at improving total seed protein content. 展开更多
关键词 COWPEA GERMPLASM PROTEIN near-infrared Spectroscopy (nirs) Partial Least Squares (PLS)
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Noninvasive Detection of Cerebral Blood Flow and Blood Oxygen Based on Inductive Sensing Technology and Near Infrared Spectroscopy
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作者 Cheng Zhou Zexiang Lyu +6 位作者 Maoting Zhang Xin Zou Liang Wei Feng Wang Mingxin Qin Jia Xu Jian Sun 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期204-212,共9页
The synchronous monitoring of cerebral blood flow and blood oxygen levels plays a pivotal role in the prevention,diagnosis,and treatment of cerebrovascular diseases.This study introduces a novel noninvasive device uti... The synchronous monitoring of cerebral blood flow and blood oxygen levels plays a pivotal role in the prevention,diagnosis,and treatment of cerebrovascular diseases.This study introduces a novel noninvasive device utilizing inductive sensing and near-infrared spectroscopy technology to facilitate simultaneous monitoring of cerebral blood flow and blood oxygen levels.The device consists of modules for cerebral blood flow monitoring,cerebral blood oxygen monitoring,control,communication,and a host machine.Through experiments conducted on healthy subjects,it was confirmed that the device can effectively achieve synchronous monitoring and recording of cerebral blood flow and blood oxygen signals.The results demonstrate the device’s capability to accurately measure these signals simultaneously.This technology enables dynamic monitoring of cerebral blood flow and blood oxygen signals with potential clinical applications in preventing,diagnosing,treating cerebrovascular diseases while reducing their associated harm. 展开更多
关键词 cerebrovascular disease synchronous monitoring inductive sensing near infrared spec-troscopy(nirs)
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Evaluation of Expression Recognition Function in Autism Spectrum Disorder Using Near-Infrared Spectroscopy 被引量:1
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作者 Kaoru Furukawa Kenji Mori +4 位作者 Keiko Mori Saori Nakano Kumi Takahashi Hiroko Hashimoto Tetsuya Tanioka 《Open Journal of Psychiatry》 2018年第1期35-49,共15页
One of the characteristics of Autism Spectrum Disorder (ASD) is social disorder. The specificity of facial and expression recognition for people with ASD is gathering attention as a factor of this social disorder. The... One of the characteristics of Autism Spectrum Disorder (ASD) is social disorder. The specificity of facial and expression recognition for people with ASD is gathering attention as a factor of this social disorder. The study examined the hemodynamic activities in the prefrontal cortex using near-infrared spectroscopy (NIRS) when a person with ASD performed an expression recognition task. The subjects were twenty males (18 - 22 years old) with ASD and without intellectual disabilities. Forty-five healthy males matched for age and sex were included as a control group. In both groups, the degree of autistic tendencies was evaluated using the Autism-Spectrum Quotient (AQ). Using eight standard emotional expressions of Japanese people, two expression recognition tasks were set. An NIRS was used to measure the prefrontal cortex blood mobilization during the expression-processing process. The AQ was significantly higher in the ASD group, while the rate of overall correct expression response was significantly lower (p &rho;= &minus;0.40 p < 0.001). In the automatic expression-processing task, no activation in the prefrontal cortex was found in either the ASD or the control group. In the conscious expression-processing task, the activation of the left and right lateral prefrontal cortex was weaker in the ASD group compared to the control group. Unlike in the control group, a mild activation of posterior prefrontal cortex was found in the ASD group. The expression-processing process of the ASD group was found to be different from that of the control group. NIRS was effective in detecting a brain function disorder in people with ASD during an expression-processing process. 展开更多
关键词 AUTISM spectrum Disorder near-infrared Spectroscopy Autism-spectrum QUOTIENT FACIAL Expression Recognition PREFRONTAL CORTEX
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Detection of Chlorpyrifos Residues in Akesu Red Fuji Apple based on Near Infrared Spectrum
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作者 Zhang Nannan Zhang Xiao 《Plant Diseases and Pests》 CAS 2018年第2期28-32,42,共6页
[Objective] The paper was to explore a method for detecting chlorpyrifos residues in red Fuji apple. [Method] The original spectral data of apple samples sprayed with different volume fractions of chlorpyrifos were co... [Objective] The paper was to explore a method for detecting chlorpyrifos residues in red Fuji apple. [Method] The original spectral data of apple samples sprayed with different volume fractions of chlorpyrifos were collected using near infrared spectrometer at the band of 4 000-10 000 cm^(-1). The original spectra were pre-treated by a variety of methods, and partial least squares(PLS) model was established for predictive analysis. [Result] Near infrared spectrum showed sensitivity to apple samples sprayed with different volume fractions of chlorpyrifos, but had low precision on pesticide-free samples. Data of blank control group were further eliminated for modeling prediction. The results showed that the results were the best when pre-treated with first derivative(FD): R=0.987 9; the square error of prediction(SEP) was 0.173 6; the root-mean-square error of cross-validation(RMSECV) was 0.120 5; and the precision was 0.923 4. [Conclusion] Near infrared spectrum can better predict chlorpyrifos residue, providing a new method for detecting chlorpyrifos residues in Akesu red Fuji apple. 展开更多
关键词 near infrared spectrum Akesu red Fuji apple CHLORPYRIFOS Pesticide residue Partial least squares (PLS)
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Simulation and Modelling of near Infrared Spectroscopy (NIRS) as Brain Monitor
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作者 Mohamed Shaaban Ali 《Spectral Analysis Review》 2014年第2期3-5,共3页
Near infrared spectroscopy (NIRS) is a method for non-invasive monitoring of cerebral oxygenation and haemodynamics. Different devices provide information on changes of oxygenated (HbO2) and deoxygenated haemoglobin (... Near infrared spectroscopy (NIRS) is a method for non-invasive monitoring of cerebral oxygenation and haemodynamics. Different devices provide information on changes of oxygenated (HbO2) and deoxygenated haemoglobin (HHb), oxidized cytochrome aa3 (CytOx) or regional oxygen saturation (rSO2). NIRS has been used during adult and paediatric cardiac surgery. 展开更多
关键词 near infrared SPECTROSCOPY (nirs)
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Investigation of Prefrontal Cortex Activity in University Students with Presenteeism: A Near-Infrared Spectroscopy (NIRS) Study
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作者 Masateru Matsushita Schuhei Yamamura Manabu Ikeda 《Journal of Behavioral and Brain Science》 2015年第9期339-347,共9页
Presenteeism refers to impaired performance attributed to attending work with health problems. There has been no study examining the state of presenteeism with objective measures. We compared cerebral hemodynamic chan... Presenteeism refers to impaired performance attributed to attending work with health problems. There has been no study examining the state of presenteeism with objective measures. We compared cerebral hemodynamic changes, measured by near-infrared spectroscopy (NIRS), during neuropsychological tests conducted by university students with presenteeism and healthy controls. Twenty-two university students participated in the study;11 of them with impaired performance caused by mental health problem were allocated to the presenteeism group and 11 without health problems to the control group. Presenteeism was assessed by the Presenteeism Scale for Students. To evoke hemodynamics changes, the participants completed a Word Fluency Test (WFT) and a Trail Making Test (TMT). The NIRS probes were located over the bilateral prefrontal area. Students with presenteeism had significantly higher incidences of depression than controls. However, there was no significant difference in behavioral performance examinations between the two groups. With regard to hemodynamics changes, the repeated measures analysis of covariance of the NIRS signals revealed significant interactions between group and task activation. Although we observed a significant increase in oxygenated hemoglobin concentration during the WFT among controls (simple main effect;left channel, F(1, 19) = 27.34, P F(1, 19) = 22.05, P < 0.001), no changes were found in students with presenteeism during either the WFT (simple main effect;left channel, F(1, 19) = 0.12, P F(1, 19) = 0.08, P t = ﹣0.94, P with Bonferroni correction = 0.745;right channel, t = ﹣2.19, P with Bonferroni correction < 0.113). This is the first study to reveal differences in activity in the cerebral cortex associated with presenteeism. The fact that students with presenteeism have prefrontal dysfunction might reinforce the concept of presenteeism. 展开更多
关键词 ABSENTEEISM ADOLESCENT Health near-infrared Spectroscopy (nirs) PRESENTEEISM School REFUSAL
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Correlation of prefrontal activity measured by near-infrared spectroscopy (NIRS) with mood, BDNF genotype and serum BDNF level in healthy individuals
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作者 Daisuke Matsuzawa Kotaro Takeda +8 位作者 Hiroyuki Ohtsuka Jun Takasugi Takashi Watanabe Junko Maeda Saeka Nagakubo Chihiro Sutoh Ichiro Shimoyama Ken Nakazawa Eiji Shimizu 《Open Journal of Psychiatry》 2012年第3期194-203,共10页
Depression has been known to reduce the prefrontal activity associated with the execution of certain cognitive tasks, although whether a temporarily depressed or anxious mood in healthy individuals affects the prefron... Depression has been known to reduce the prefrontal activity associated with the execution of certain cognitive tasks, although whether a temporarily depressed or anxious mood in healthy individuals affects the prefrontal blood oxygen level during cognitive tasks is unknown. Combining the measurement of prefrontal activity with near-infrared spectroscopy (NIRS) and the two cognitive tasks, namely the letter version of the verbal fluency test (VFT-l) and the Stroop test, we measured the effect of a depressed or anxious mood and gender on the changes in the prefrontal oxygenated hemoglobin (Oxy-Hb) levels during those cognitive tests in healthy individuals. Depressed mood or anxious mood was assessed by the Hospital Anxiety and Depression Scale (HADS). Thereby we aimed to explore the possibility of NIRS measurement for detecting the early subclinical manifestation of major depression. Moreover, we examined the possible relationships between prefrontal activation and the functional Val66Met polymorphisms of the brain derived neurotropic factor (BDNF) gene and serum BDNF level. As a result, the increased prefrontal Oxy-Hb levels during cognitive tasks were significantly correlated with the severity of depressed mood in males. The course of the prefrontal Oxy-Hb increase was different depending on the cognitive tasks, i.e., the VFT-l or the Stroop test, in both genders. Correlations of BDNF genotype and serum BDNF level with the prefrontal Oxy-Hb levels during those cognitive tasks were negative. Our results suggest that the early subclinical manifestation of depressed mood in males might be detected by the NIRS measurement, which is not correlated with the individual properties of BDNF. 展开更多
关键词 near-infrared Spectroscopy (nirs) Depression ANXIETY Brain Derived Neurotropic Factor (BDNF)
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NIRS-XRF联用的煤炭发热量高稳定检测 被引量:5
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作者 宋健超 张雷 +2 位作者 马维光 尹王保 贾锁堂 《光学精密工程》 EI CAS CSCD 北大核心 2023年第13期1880-1889,共10页
实时获知煤炭发热量对于及时调整电站锅炉风粉配比和提高煤炭燃烧效率具有重要意义,为了实现电力生产中发热量的稳定快速检测,提出了一种近红外光谱(Near Infrared Spectroscopy, NIRS)与X射线荧光光谱(X-ray Fluorescence, XRF)联用的... 实时获知煤炭发热量对于及时调整电站锅炉风粉配比和提高煤炭燃烧效率具有重要意义,为了实现电力生产中发热量的稳定快速检测,提出了一种近红外光谱(Near Infrared Spectroscopy, NIRS)与X射线荧光光谱(X-ray Fluorescence, XRF)联用的煤炭发热量高稳定检测方法,它结合了NIRS能高稳定检测煤中与发热量正相关的有机基团的优势与XRF能高稳定检测与发热量负相关的成灰元素的特点,大大提高了对煤炭发热量的测量重复性。在光谱预处理中,先将两套光谱融合作为偏最小二乘回归的输入变量进行全谱初步建模,依据回归系数选择NIRS光谱中的有效波段,再将它与XRF光谱中的成灰元素谱线一并融合进行归一化处理。建模时将预处理后的融合光谱数据作为输入变量,利用偏最小二乘回归对煤炭发热量进行建模。实验结果表明,NIRS-XRF联用方法对定标集煤样发热量预测的线性相关度系数(R^(2))为0.995,对验证集煤样发热量预测的最小均方根误差、平均相对误差和标准偏差分别为0.24 MJ/kg,0.61%和0.05 MJ/kg,测量重复性满足小于0.12 MJ/kg的国家标准。NIRS-XRF联用的煤炭发热量高稳定检测方法有望推广应用于火力发电、煤化工、冶金、水泥和焦化等“高碳”行业,助力我国按期实现碳中和目标。 展开更多
关键词 近红外光谱 X射线荧光光谱 光谱融合 煤炭发热量 高稳定检测
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Determination of Protein and Starch Content in Whole Maize Kernel by Near Infrared Reflectance Spectroscopy 被引量:2
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作者 WEILiang-ming YANYan-lu DAIJing-rui 《Agricultural Sciences in China》 CAS CSCD 2004年第7期490-495,共6页
Using 128 bulk-kernel samples of inbred lines and hybrids, a study was conducted toinvestigate the feasibility and method of measuring protein and starch contents inintact seeds of maize by near infrared reflectance s... Using 128 bulk-kernel samples of inbred lines and hybrids, a study was conducted toinvestigate the feasibility and method of measuring protein and starch contents inintact seeds of maize by near infrared reflectance spectroscopy (NIRS). The chemometricalgorithms of partial least square (PLS) regression was used. The results indicated thatthe calibration models developed by the spectral data pretreatment of firstderivative+multivariate scattering correction within the spectral region of 10000-4000cm-1, and first derivative + straight line subtraction in 9000-4000cm-1 were thebest for protein and starch, respectively. All these models yielded coefficients ofdetermination of calibration (R2cal) above 0.97, while R2cv and R2val of cross and externalvalidation ranged from 0.92 to 0.95, respectively; however, the root of mean squareerrors of calibration, cross and external validation (RMSEE, RMSECV and RMSEP) werebelow 1(ranged 0.3-0.7),respectively. This study demonstrated that it is feasible touse NIRS as a rapid, accurate, and none-destructive technique to predict protein andstarch contents of whole kernel in the maize quality improvement program. 展开更多
关键词 MAIZE near infrared reflectance spectroscopy (nirs) Protein and starch CALIBRATION model
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Electronic structure and infrared spectrum of a W_n C^(0,±) (n = 1-6) cluster 被引量:1
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作者 张秀荣 康张李 郭文录 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期204-211,共8页
WnC0'± (n= 1-6) clusters are investigated by using the density functional theory (DFT) at the B3LYP/LANL2DZ level. We find that the neutral, anionic and cationic ground state structures are similar within th... WnC0'± (n= 1-6) clusters are investigated by using the density functional theory (DFT) at the B3LYP/LANL2DZ level. We find that the neutral, anionic and cationic ground state structures are similar within the same size, and constituted by substituting a C atom for one W atom in the structures of Wn+1 clusters. The natural bond orbital (NBO) charge analyses indicate that the direction of electron transfer is from the W atom to the 2p orbital of the C atom. In addition, the calculated infrared spectra of the WnC0'± (n= 2-6) clusters manifest that the vibrational frequencies of neutral, anionic and cationic clusters are similar in a range of 80 cm-1-864 cm-1. The high frequency, strong peak modes are found to be an almost stretched deformation of the carbide atom. Finally, the polarizabilities of WnC0'± (n= 1-6) clusters are also discussed. 展开更多
关键词 WnC0'± (n= 1-6) clusters electronic structure infrared spectrum density functionaltheory
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Moisture content in raw rubber sheet analyzed by transflectance near infrared spectroscppy 被引量:1
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作者 Ronnarit Rittiron Worapa Seehalak 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2014年第4期51-56,共6页
Moisture content is an important trait for rubber sheet trading system.Therefore,a calibrationequation for predicting moisture content was created by near infrared(NIR)technique in order todevelop a more fair trading ... Moisture content is an important trait for rubber sheet trading system.Therefore,a calibrationequation for predicting moisture content was created by near infrared(NIR)technique in order todevelop a more fair trading system in Thailand.Spectra were recorded in two systems.One wasmeasurement on each rubber sheet and the other was on a pile of sheets.Both were[measured by ahandheld NIR spectrometer in the short wavelength region(700-1100 nm)in the transflectancemode using Teflon as a diffuse refector.The spectra showed the peak at about 900 nm whichbelongs to isoprene,the major component of rubber sheet.Pretreatment with second derivativewas applied to remove baseline shift effect occurring due to thickness differences on each rubber sheet.From validation results,moisture contents predicted by single sheet system were moreaccurate than a pile of sheet system with standard error of prediction(SEP)=0.39 %and bias of-0.07%,and they were not significantly diferent from the actual values at 95%confidence.As aresult,determining moisture content in each rubber sheet by a handheld NIR,spectrometerprovided accurate values,easy and rapid operation. 展开更多
关键词 NIR QUALITY rubber sheet:trading system handheld near infrared spectrometer
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Quantitative Analysis of Berberine in Processed Coptis by Near-Infrared Diffuse Reflectance Spectroscopy 被引量:4
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作者 ZHANG Yong XIE Yun-fei +3 位作者 SONG Feng-rui LIU Zhi-qiang CONG Qian ZHAO Bing 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第6期717-721,共5页
The near-infrared(NIR) diffuse reflectance spectroscopy was used to study the content of Berberine in the processed Coptis. The allocated proportions of Coptis to ginger, yellow liquor or Evodia rutaecarpa changed a... The near-infrared(NIR) diffuse reflectance spectroscopy was used to study the content of Berberine in the processed Coptis. The allocated proportions of Coptis to ginger, yellow liquor or Evodia rutaecarpa changed according to the results of orthogonal design as well as the temperature. For as withdrawing the full and effective information from the spectral data as possible, the spectral data was preprocessed through first derivative and multiplicative scatter correetion(MSC) according to the optimization results of different preprocessing methods. Firstly, the model was established by partial least squares(PLS); the coefficient of determination(R2) of the prediction was 0.839, the root mean squared error of prediction(RMSEP) was 0.1422, and the mean relative error(RME) was 0.0276. Secondly, for reducing the dimension and removing noise, the spectral variables were highly effectively compressed via the wavelet transformation(WT) technology and the Haar wavelet was selected to decompose the spectral signals. After the wavelet coefficients from WT were input into the artificial neural network(ANN) instead of the spectra signal, the quantitative analysis model of Berberine in processed Coptis was established. The R^2 of the model was 0.9153, the RMSEP was 0.0444, and the RME was 0.0091. The values of appraisal index, namely R^2, RMSECV, and RME, indicate that the generalization ability and prediction precision of ANN are superior to those of PLS. The overall results show that NIR spectroscopy combined with ANN can be efficiently utilized for the rapid and accurate analysis of routine chemical compositions in Coptis. Accordingly, the result can provide technical support for the further analysis of Berberine and other components in processed Coptis. Simultaneously, the research can also offer the foundation of quantitative analysis of other NIR application. 展开更多
关键词 near-infrared(NIR) spectroscopy Partial least squares Artificial neural network Wavelet transformation BERBERINE
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Influence of Transparent Anode on Luminescent Performance of Near-infrared Organic Light-emitting Diodes 被引量:2
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作者 GUAN He-song CHENG Chuan-hui +6 位作者 LI Wan-cheng GENG Dong-feng FAN Zhao-qi CHANG Yu-chun ZHAO Wang GUO Zhen-qiang DU Guo-tong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第6期786-790,共5页
The optical transmission(200--2000 nm), sheet resistance and work functions of indium-tin oxide(ITO)(100 Ω/), ITO(12 Ω/), zinc-oxide(ZnO), aluminum-doped ZnO(AZO) and polyaniline(PANI) films were inves... The optical transmission(200--2000 nm), sheet resistance and work functions of indium-tin oxide(ITO)(100 Ω/), ITO(12 Ω/), zinc-oxide(ZnO), aluminum-doped ZnO(AZO) and polyaniline(PANI) films were investigated. Near-infrared organic light-emitting diodes(NIR-OLEDs) emitting around 1.54 μm based on Er(DBM)3Phen with ITO(100 Ω/), ITO(12 Ω/) and PANI as anodes, respectively, were fabricated. The device structure was anode/4"-tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine(m-MTDATA)/ N,N'-di-l-naphthyl- N,N'-diphenylbenzidine(NPB)/Er(DBM)3Phen/tris-(8-hydroxyquinoline) aluminum(Alq3)/A1. The results suggest that the performance of NIR-OLEDs with ITO(100 Ω/), which has a lower Sn content, as anodes appear to be better than that of NIR-OLEDs with ITO(12 Ω/) and PANI as anodes, respectively. The high N1R transmittance of ITO(100 Ω/) is a major reason for the relatively high NIR EL efficiency. The more balanced holes and electrons in the device based on ITO(100 Ω/) are another reasons. 展开更多
关键词 Transparent electrode near-infrared(NIR) Organic light-emitting diode(OLED)
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On-Line Measurement of the Chemical Oxygen Demand in Wastewater in a Pulp and Paper Mill Using Near Infrared Spectroscopy 被引量:5
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作者 John Dahlbacka Josefina Nystrom +2 位作者 Torgny Mossing Paul Geladi Tom Lillhonga 《Spectral Analysis Review》 2014年第4期19-25,共7页
Although near infrared (NIR) spectroscopy has been evaluated for numerous applications, the number of actual on-line or even on-site industrial applications seems to be very limited. In the present paper, the attempts... Although near infrared (NIR) spectroscopy has been evaluated for numerous applications, the number of actual on-line or even on-site industrial applications seems to be very limited. In the present paper, the attempts to produce online predictions of the chemical oxygen demand (COD) in wastewater from a pulp and paper mill using NIR spectroscopy are described. The task was perceived as very challenging, but with a root mean square error of prediction of 149 mg/l, roughly corresponding to 1/10 of the studied concentration interval, this attempt was deemed as successful. This result was obtained by using partial least squares model regression, interpolated reference values for calibration purposes, and by evenly distributing the calibration data in the concentration space. This work may also represent the first industrial application of online COD measurements in wastewater using NIR spectroscopy. 展开更多
关键词 Chemical Oxygen Demand (COD) Industrial Wastewater near infrared Spectroscopy (NIR) Multivariate Calibration On-Line Measurement
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MODIFICATION OF ABSORPTION SPECTRUM OF GaAs/AlGaAs QUANTUM WELL INFRARED PHOTODETECTOR BY POSTGROWTH ADJUSTMENT 被引量:2
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作者 Y FU YANG Chang-Li 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2006年第1期1-5,共5页
Quantum well intermixing techniques modify the geometric shape of quantum wells to allow postgrowth adjustments.The tuning effect on the optical response property of a GaAs/AlGaAs quantum well infrared photodetector(Q... Quantum well intermixing techniques modify the geometric shape of quantum wells to allow postgrowth adjustments.The tuning effect on the optical response property of a GaAs/AlGaAs quantum well infrared photodetector(QWIP) induced by the interdifussion of Al atoms was studied theoretically.By assuming an improvement of the heterointerface quality and an enhanced Al interdiffusion caused by postgrowth intermixings,the photoluminescence spectrum shows a blue-shifted,narrower and enhanced photoluminescence peak.The infrared optical absorption spectrum also shows the expected redshift of the response wavelength.However,the variation in the absorption peak intensity depends on the boundary conditions of the photo generated carriers.For high-quality QWIP samples,the mean free path of photocarriers is long so that the photocarriers are largely coherent when they transport across quantum wells.In this case,the enhanced Al interdiffusion can significantly degrade the infrared absorption property of the QWIP.Special effects are therefore needed to maintain and/or improve the optical properties of the QWIP device during postgrowth treatments. 展开更多
关键词 吸收光谱 量子阱 红外光电探测器 修正
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Geographic Classification of Chinese Grape Wines by Near-Infrared Reflectance Spectroscopy 被引量:1
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作者 赵芳 赵育 +1 位作者 毛文华 战吉宬 《Journal of Donghua University(English Edition)》 EI CAS 2012年第1期40-45,共6页
Near-infrared reflectance spectroscopy (NIRS) was applied to classify grape wines of different geographical origins (Changli, Huailai, and Yantai, China). Near infrared (NIR) spectra were collected in transmission mod... Near-infrared reflectance spectroscopy (NIRS) was applied to classify grape wines of different geographical origins (Changli, Huailai, and Yantai, China). Near infrared (NIR) spectra were collected in transmission mode in the wavelength range of 800-2500 nm. Wines (n=90) were randomly split into two sets, calibration set (n=54) and validation set (n=36). Discriminant analysis models were developed using BP neural network and discriminant partial least-squares discriminant analysis (PLS-DA). The prediction performance of calibration models in different wavelength range was also investigated. BP neural network models and PLS-DA models correctly classified 100% of the wines in calibration set. When used to predict wines in validation set, BP neural network models correctly classified 100%, 81.8%, and 90.9% of the wines from Changli, Huailai, and Yantai respectively, and PLS-DA models correctly classified 100% of all samples. The results demonstrated that NIRS could be used to discriminate Chinese grape wines as a rapid and reliable method. 展开更多
关键词 near-infrared reflectance spectroscopy (nirs) Chinese grape wines discriminant analysis models BP neural network PLS-DA
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Lateralization of Receptive Language Function Using near Infrared Spectroscopy
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作者 Paquette Natacha Gonzalez-Frankenberger Berta +5 位作者 Vannasing Phetsamone Tremblay Julie Florea Olivia Beland Renée Lepore Franco Lassonde Maryse 《Neuroscience & Medicine》 2010年第2期64-70,共7页
In recent decades, functional magnetic resonance imaging (fMRI) has proven to be more effective than the Wada test in the evaluation of language lateralization in special populations such as epileptic patients and chi... In recent decades, functional magnetic resonance imaging (fMRI) has proven to be more effective than the Wada test in the evaluation of language lateralization in special populations such as epileptic patients and children. However, fMRI requires that subjects remain motionless during data acquisition, making the assessment of receptive and expressive language difficult in young children and population with special needs. Near-Infrared spectroscopy (NIRS) is a non- invasive technique that has proven to be more tolerant to motion artifacts. The aim of the present study was to investigate the use of NIRS to assess receptive language patterns using a story listening paradigm. Four native French-speakers listened to stories read aloud by a bilingual speaker in both French and Arabic. To determine if the signal recorded was affected by episodic memory processes, a familiar story and an unknown story were presented. Results showed that listening to stories in French elicited a significantly higher left lateralized response than listening to stories in Arabic, independently of the familiarity of the story. These results confirm that NIRS is a useful non-invasive technique to assess receptive language in adults and can be used to investigate language lateralization among children and epileptic patients slated for epilepsy surgery. 展开更多
关键词 LANGUAGE LATERALIZATION near infrared Spectroscopy (nirs) Optical Imaging BRAIN Mapping EPILEPSY
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Rapid, Non-Destructive, Textile Classification Using SIMCA on Diffuse Near-Infrared Reflectance Spectra 被引量:2
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作者 Christopher B. Davis Kenneth W. Busch +2 位作者 Dennis H. Rabbe Marianna A. Busch Judith R. Lusk 《Journal of Modern Physics》 2015年第6期711-718,共8页
Soft independent modeling of class analogy (SIMCA) was successful in classifying a large library of 758 commercially available, non-blended samples of acetate, cotton, polyester, rayon, silk and wool 89% - 98% of the ... Soft independent modeling of class analogy (SIMCA) was successful in classifying a large library of 758 commercially available, non-blended samples of acetate, cotton, polyester, rayon, silk and wool 89% - 98% of the time at the 95% confidence level (p = 0.05 significance level). In the present study, cotton and silk had a 62% and 24% chance, respectively, of being classified with their own group and also with rayon. SIMCA correctly identified a counterfeit “silk” sample as polyester. When coupled with diffuse NIR reflectance spectroscopy and a large sample library, SIMCA shows considerable promise as a quick, non-destructive, multivariate method for fiber identification. A major advantage is simplicity. No sample pretreatment of any kind was required, and no adjust-ments were made for fiber origin, manufacturing process residues, topical finishes, weave pattern, or dye content. Increasing the sample library should make the models more robust and improve identification rates over those reported in this paper. 展开更多
关键词 DIFFUSE near-infrared (NIR) Reflectance Spectroscopy CHEMOMETRICS Soft Independent Modeling of Class ANALOGY (SIMCA) Pattern Recognition TEXTILE Identification Multivariate Analysis
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Application of Short-wave Near-infrared Reflectance Spectroscopy in Controlling Extract of Fructus Cnidii Using Supercritical Carbon Dioxide 被引量:1
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作者 MI Hong GUO Ye +4 位作者 LI Wen-liang Qu Nan DOU Ying REN Yu-qiu REN Yu-lin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第1期116-119,共4页
Fructus cnidii (Chinese name shechuangzi) is the fruit produced by Cnidium monnieri (L.) Cusson (Umbelliferae). It is a perennial herb that is used to treat skin-related diseases and gynecopathyell. Recent pharm... Fructus cnidii (Chinese name shechuangzi) is the fruit produced by Cnidium monnieri (L.) Cusson (Umbelliferae). It is a perennial herb that is used to treat skin-related diseases and gynecopathyell. Recent pharmacological studies have revealed crude extracts or components isolated from fructus cnidii possess antiallergic, antipruritic, antidermatophytic, antibacterial, antifungal, and antiosteoporotic activities. Osthole and imperatorin are the major compounds present in shechuangzi. They are often used as standards for the evaluation of the quality of shechuangzi products. 展开更多
关键词 Fructus cnidii Supercfitical carbon dioxide Short-wave near-infrared diffuse reflectance spectrum Artificial neural network Degree of approximation
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Preparation of Ultrafine SiO2 Powder from Rice Husk and Properties of Its Infrared Spectrum
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作者 晋日亚 胡双启 谭迎新 《Journal of Measurement Science and Instrumentation》 CAS 2011年第3期226-229,共4页
This paper discussed impact of temperature on the size distribution in preparing ultrafine silica from rice husk.The samples prepared were analyzed with infrared spectrum,and the relation between the particle size and... This paper discussed impact of temperature on the size distribution in preparing ultrafine silica from rice husk.The samples prepared were analyzed with infrared spectrum,and the relation between the particle size and intensity of characteristic absorption peak of IR at center around 1 100 cm-1 was disscussed with the baseline method.Results show that when the temperature is 650 ℃ and roasting time is 11 h,at optimal reaction conditions,the size distribution of the ultrafine silica powder prepared is relatively concentrated,and the average particle size is 199.5 nm.Moreover,the characteristic absorption band of IR is broadening gradually along with particle size decreasing. 展开更多
关键词 rice husk ultrafine powder SIO2 infrared spectrum
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