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1
Summerfield, Stephen. "Near infrared fluorescence spectroscopy." Thesis, Loughborough University, 1993. https://dspace.lboro.ac.uk/2134/10601.
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Fluorimetry in the very near infrared region ca. 600-1000nm is a new approach to photochemical analysis. The advantages include greatly reduced background fluorescence signals from important sample matrices (such as blood serum), reduced scattering, and reduced probability of sample decomposition. Also, the availability of low cost, efficient, stable and robust optical components (e.g. laser diodes and light emitting diodes), solid state detectors (e.g. single silicon photodiodes and diode arrays) and fibre optics, allows the construction of an inexpensive fluorimeter. In the near infrared region, there are some very bright fluorophores that can be adapted for use as fluorescent probes, labels for immunoassay, and as ion-pair agents. The advantageous performance of most types of fluorimetric analysis now undertaken In the ultraviolet and visible region of the spectrum may therefore be extended into the longer wavelength region. Excellent limits of detection are attainable, and some near infrared fluorophores show invaluable fluorescence probe properties, such as Nile Red. The most useful of the dye groups investigated were the phenoxazines and thiazines. Reactive derivatives of these dyes show great potential as fluorescent labels for Immunoassay. These dyes have also been used as probes due to their solvatochromism and sensitivity to pH.
2
Wruck, Eric Michael. "Applying near-infrared spectroscopy (nirs)." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2386.
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Over recent decades, much has been learned about the perceptual capacity that
enables infants to recognize and understand language. However, not until very recently
have the neural mechanisms that are the substance of language learning been
investigated. A recently developed optical imaging technique called near-infrared
spectroscopy (NIRS) shows promise for being an acceptable alternative to invasive
imaging techniques. NIRS measures correlates of neural activity by assessing
hemoglobin concentration changes in the infant brain. The research presented here
investigates neural activation in the left temporal and occipital cortex regions during
exposure to speech and visual stimuli. As hypothesized, hemodynamic reaction was
observed in both areas. Results indicate a significant activation in response to speech in
the left temporal region, and an intriguing difference between uni- and bi-modally
presented speech stimuli. These results have interesting implications for future multimodal
studies of infant speech perception.
3
Ennico, Kimberly Ann. "Near infrared faint object spectroscopy." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.625052.
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Angus, Caroline. "Near infrared spectroscopy and exercise." Thesis, University of Essex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274298.
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Prestwich, Andrea Heather. "Near infrared spectroscopy of galaxies." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47622.
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Williams, David James. "Near infrared spectroscopy in cerebrovascular disease." Thesis, University of Bath, 2002. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426180.
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7
Todd, Stephen Peter. "Near-infrared integral field spectroscopy with UIST." Thesis, University of Edinburgh, 2004. http://hdl.handle.net/1842/27542.
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UIST is a facility class near-infrared imager and spectrometer, built at the UK Astronomy Technology Centre (UKATC) in Edinburgh, and now in use at the UK Infrared Telescope (UKIRT). UIST operates at wavelengths of 1-5 μm, providing a variety of imaging and spectrometry modes. UIST is the first instrument to include a cryogenic deployable integral field unit (IFU), allowing integral field spectroscopy to be carried out over a 3.3 x 6.0 arcsec field of view using any of the grisms available for spectroscopy in UIST. The optical components of the image slicing IFU were tested and aligned on the bench before the IFU was integrated into UIST for cryogenic tests in the laboratory in Edinburgh and on the telescope. These tests included measurements of the image quality produced by the IFU and the transmission of the IFU relative to a slit of equivalent width as a function of wavelength, found to increase from 0.4 at 1 μm to 0.62 at 2.5 μm. When the seeing is poor and high spectral resolution is required the loss of light in the IFU may be significantly less than the slit-losses from a conventional slit. The conditions under which use of the IFU may be preferable to use of a silt are discussed. The data reduction methods used to automatically combine IFU observations with arc-lamp spectra, flat-field frames and standard-star spectra in order to transform the two-dimensional output of the IFU into a calibrated (x, y, l) datacube in near real-time and the procedures required to obtain the necessary calibration data are outlined. An example of one type of observation made possible by the IFU is shown by observations of H2 lines excited in bow-shocks in the outflow from a young star in the vicinity of the ultra-compact H II region G25.65-1.05, allowing measurement of the spatial variation of the excitation temperature in these shocks.
8
Casselgren, Johan. "Road surface classification using near infrared spectroscopy." Licentiate thesis, Luleå : Luleå University of Technology, 2007. http://epubl.ltu.se/1402-1757/2007/42/LTU-LIC-0742-SE.pdf.
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9
Kelly, Douglas Michael. "Near-infrared spectroscopy as an astrophysical tool." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185983.
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Recent improvements in infrared detector arrays make it possible for the first time to conduct detailed spectroscopic studies of a complete range of objects in the 0.9-1.35 μm region. In this dissertation, I examine the 0.9-1.35 μm spectra of planetary and proto-planetary nebulae, M dwarfs, young stellar objects, Seyfert galaxies, an H II region, and a Wolf-Rayet star. Line identifications are made for each of these objects, and extensive line lists are presented. I also investigate what the lines can tell us about each object. The 0.9-1.35 μm spectrum of the proto-planetary nebula AFGL 618 is dominated by recombination lines, low-ionization, shock-excited lines, and thermal and fluorescent H₂ lines. We use ratios of forbidden lines to show that there are two distinct physical regions in the lobes of AFGL 618, including one which must have been excited by shocks. We also show that the H₂ lines in the 0.9-1.35 μm region are ideal for detecting low levels of fluorescent H₂ emission, even when a strong thermal component is present. We present 0.6-1.5 μm spectra for M dwarfs ranging from M2 through M9. These spectra are compared with recent theoretical models, and a temperature scale is determined. In late-M dwarfs, the shape of the infrared spectrum and the depth of the 1.35 μm H₂O feature are good temperature indicators. The temperatures we derive for the M dwarfs are higher than the temperatures found in earlier studies and are in closer agreement with theoretical tracks of the lower main sequence. We present 0.9-1.35 μm spectra for 7 young stellar objects. These objects exhibit a wide variety of behavior, including strong fluorescent emission. We show that the infrared spectra can be used to study all of the regions that are detected with visible and red spectra. As a result, 0.9-1.35 μm spectroscopy should be quite useful for studying heavily embedded sources. The 0.9-1.35 μm spectra of high-excitation objects include a number of distinctive features including He II lines, several high ionization lines, and very strong (S III) lines. We find that the excitation level of a source can be estimated based on these features alone.
10
Gresham, Christopher Allen 1965. "Near-infrared spectroscopy utilizing array detector technology." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282690.
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A near-infrared spectrometer incorporating solid-state design applicable for industrial quantitative/qualitative process monitoring analysis is presented. The solid-state near-infrared spectrometer provides inherent wavelength stability necessary for long term calibration accuracy. The spectrometer consists of a 24 volt, 10 watt quartz-halogen-tungsten regulated source with optical feedback. Wavelength dispersion was accomplished using a 50 μm entrance slit, f/4, 0.25 meter spectrograph equipped with astigmatism correcting toroidal mirrors and a 300 gr/mm plane reflectance ruled grating blazed for 2000 nm peak efficiency. A 1024 element backside- illuminated Schottky-barrier PtSi photodiode array detector with wavelength response from 900-5000 nm and peak quantum efficiency of 8% at 1100 nm was operated using cryogenic cooling to reduce dark response. A readout rate of 31.25 kHz produced 41 msec integration time per array read. The readout was digitized to 16 bit resolution for subsequent data storage. This system demonstrated 1.5 nm spectral bandpass, 3 orders linear dynamic range and typical baseline rms noise level of 10⁻⁴ a.u. Using this system, quantitative/qualitative chemical analyses were performed focusing on industrial analytical chemical applications. Simultaneous quantitative multcomponent xylene isomer mixtures analysis was achieved using the solid-state near-infrared spectrometer coupled with partial least squares regression multivariate data treatment. The results demonstrate an absolute accuracy of ± 0.05, ±0.12 and ±0.09% w/v for o-, m- and p-xylene isomers respectively. In a separate chemical study, qualitative classification analysis of specially denatured alcohol mixtures was successfully performed on 53 validation samples using 35 reference samples belonging to 12 classes. The validation set included mixture sample types used for model calibration as well as others composed of compounds not used for model calibration. The multivariate cluster classification method using principal components was employed to correctly classify 100% of the validations samples analyzed. The solid-state near-infrared spectrometer was also applied for direct reaction monitoring of the O-H overtone absorption band at 1411 nm for the reaction between triisopropyl-chlorosilane and methanol. The results illustrated the utility of near-infrared functional group monitoring of reactions at relatively high concentrations for information elucidation concerning reaction initiation and completion.
11
Miller, Charles Edward. "Analysis of synthetic polymers by near-infrared spectroscopy /." Thesis, Connect to this title online; UW restricted, 1989. http://hdl.handle.net/1773/11580.
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12
Howard, Daryl L., and n/a. "Hydrogen bonding in the near infrared." University of Otago. Department of Chemistry, 2006. http://adt.otago.ac.nz./public/adt-NZDU20060823.150321.
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OH-stretching spectra of various vapour phase species were recorded to investigate hydrogen bonding. The species studied include 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, acetylacetone, hexafluoroacetylacetone and the complex formed in the heterogeneous mixture of methanol and trimethylamine. The spectra range from the infrared, near infrared to visible wavelengths. The main focus of this study is in the near infrared region, in which the OH-stretching overtones are dominant.
The near infrared and visible spectrum of formic acid has been recorded to investigate coupling across bonds, specifically a resonance occurring between OH- and CH-stretching vibrations. The same resonance was also observed in the spectrum of 1,2-ethanediol. The spectra of deuterated isotopomers of formic acid and 1,2-ethanediol were recorded to experimentally verify the resonance.
The inherently weak nature of the vibrational overtone transitions required sensitive spectroscopic techniques to observe the spectra. The spectra were recorded with conventional long path length absorption spectroscopy and intracavity laser photoacoustic spectroscopy.
Anharmonic oscillator local mode calculations of the OH-stretching transitions were performed to simulate the observed spectra. These calculations require calculation of potential energy surfaces and dipole moment functions. Simulated spectra obtained with highly correlated ab initio methods and large basis sets have yielded the best agreement with observation.
13
Taylor, Helen Ruth, University of Western Sydney, and School of Food Sciences. "The evaluation of wort by near infrared spectroscopy." THESIS_FFS_XXX_Taylor_H.xml, 2001. http://handle.uws.edu.au:8081/1959.7/748.
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Near infrared spectroscopy (NIS) has been used routinely for many years for the measurement of grain protein and moisture in plant breeding programmes. Investigation as to the applicability of NIS to the identification from a barley breeding programme of the progeny with high malting quality potential was carried out over several harvests. The project concentrated on the determination of correlations between Hot Water Extract, Total Soluble Nitrogen, and Free Alpha Amino Nitrogen contents of worts (the extract of malt used to make beer) and NIR transmission data using the multivariate method of partial least squares regression. The correlation coefficients, for both calibration and prediction data sets, were significant and the standard error of prediction was similar to that obtained in the standard methods in the first year, but were unsatisfactory in the second. The instrument chosen for the study gave satisfactory correlations for the purpose of selection in the intermediate generations of the breeding programme with errors similar to the analytical methods, as long as a very wide range of calibration samples were collected from more than one harvest. It was shown that the use of an NIR spectrophotometer as a selection tool for malting quality within a barley breeding programme would not be sufficient to justify investment in this type of instrument for this purpose alone.Master of Science (Hons)
14
Bashir, Zareen. "Applications of near infrared spectroscopy in cerebral monitoring." Thesis, University of Manchester, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488409.
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Assi, Sulaf. "Identification of counterfeit medicines by near-infrared spectroscopy." Thesis, University of London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.528237.
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鄧勇軍 and Yung-kwan Tang. "Application of near-infrared spectroscopy in food compositionanalysis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31219962.
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Abebe, Solomon Befekadu. "Monitoring batch crystallisation processes using near infrared spectroscopy." Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446057.
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Vaidyanathan, Seetharaman. "Monitoring submerged mycelial bioprocesses using near-infrared spectroscopy." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248359.
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19
Sockalingum, Dhruvananda. "Surface enhanced Raman spectroscopy in the near-infrared." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315640.
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20
Torres, Daniel André Gonçalves. "Feasibility of near infrared spectroscopy in stroke patients." Master's thesis, Universidade da Beira Interior, 2012. http://hdl.handle.net/10400.6/1067.
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Introduction
Stroke is the main cause of death in Portugal. It is a severe pathology with a sudden
onset and with a very high demand in both time and money from the families of the affected
patients and from health organizations and social services. Inexpensive and practical
diagnostic tools that will assist in early detection and treatment are the source of numerous
studies.
The physiology behind a stroke is a sudden ischemic event in the brain. Near infrared
spectroscopy (NIRS) is a non-invasive mean of measuring cerebral perfusion in real time. Due
to its rapid and recent development few data exists about its applicability. Since NIRS detects
oxygen levels that are supposedly low due to oligemia in infarcted areas, our study tried to
ascertain the significance of NIRS measurements in stroke patients.
Objectives
-Determine which systemic factors influence rSO2 values.
-Determine NIRS viability in diagnosing and monitoring stroke patients by comparing
their values with those of healthy individuals using the reference value of 60 rSO2.
-Determine if NIRS is capable of influencing therapeutical changes in those monitored.
Methodology
This is a prospective study where we used NIRS EQUANOX® technology with 4 sensors:
2 Frontal 2 supra-auricular to compare cerebral oxygen values of rSO2 in a control sample of
60 healthy persons from two retirement homes from the geographical area of Covilhã,
Portugal and compared them with 128 stroke patients hospitalized in the Centro Hospitalar
Cova da Beira (CHCB). We also collected data consisting of: risk factors, imagiological studies
and vital signs. The hospitalized patients were monitored twice on the first day and then once
daily during the following four consecutive days for a total of five days.
The results were analyzed using SPSS ® software - version 17 for Windows ® and were
considered significant at p < 0.05. We resorted to the tests of independence Chi-square and
Mann Whitney U to analyze the relationships between variables.
Results
Our study revealed that the hospitalized stroke patients had higher rSO2 values than
healthy individuals from retirement homes, and that these higher values decreased along the
week they were hospitalized. We also found that the lesion side diagnosed by CT scan had higher rSO2 values than the contralateral healthy side. We did not find any association
between: stroke risk factors and rSO2 readings, use of thrombolysis and rSO2 measurements,
the imagiological exams and rSO2 readings (CT, TU and CU) and no association between age or
gender with rSO2 levels.
21
Pedrosa, Elisabete Trindade. "Near-infrared spectroscopy for estimating soil burn severity." Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/10708.
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Mestrado em Estudos AmbientaisForest fires are a natural phenomenon and occurred long before human kind was around, serving important ecosystem functions. In the past decades, however, some parts of the world have seen marked increases in the frequency and spatial extent of wildfires. This includes Portugal, where forest fires have, on average, affected 100.000 ha of rural lands per year since the mid1970s. In general, the direct and indirect effects of fires depend strongly on the temperatures to which vegetation and soil are exposed. In the case of wildfires – as opposed to prescribed burning or experimental fires - these temperatures can hardly ever be measured. Therefore, wildfire impacts are commonly assessed using proxies based on the consumption of the vegetation and the colour of the ashes deposited on the soil surface. These so-called burn severity indices typically provide qualitative estimates, distinguishing between low, medium and high severity. Recently, however, near- infrared (NIR) reflectance spectroscopy was successfully applied to estimate the maximum temperatures reached (MTR) by soils heated under laboratory conditions. The present study wanted to explore the potential of NIR for estimating MTR in soils burnt by wildfires. To this end, the work addressed two main topics: (i) spatial variability in the relationships between soil heating temperatures in a muffle and the corresponding NIR-based MTR estimates, both between and within study sites; (ii) the importance of this spatial variability in estimating MTRs of wildfire-burnt soil samples. A number of NIR-based models was constructed and used to predict the known MTR of laboratory-heated soil samples. One of the two long-unburnt study sites revealed marked variability over short distances, whereas the other did not. The models based on larger sample numbers, however, provided robust MTR predictions, even when these models involved samples from the two study sites. This probably reflected the sites comparable parent materials, soils and land cover (eucalypt plantations in schist soils). The best achieved models were used to estimate MTR by soil samples from a wildfire occurred in the central-north of Portugal, in the year 2010.. According to the index proposed in this work and the maximum temperatures reached estimations, the soil burn severity of the studied sites was moderate to high in surface samples, and low to moderate in the sub-surface samples.
22
Taylor, Helen Ruth. "The evaluation of wort by near infrared spectroscopy." Thesis, View thesis, 2001. http://handle.uws.edu.au:8081/1959.7/748.
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Near infrared spectroscopy (NIS) has been used routinely for many years for the measurement of grain protein and moisture in plant breeding programmes. Investigation as to the applicability of NIS to the identification from a barley breeding programme of the progeny with high malting quality potential was carried out over several harvests. The project concentrated on the determination of correlations between Hot Water Extract, Total Soluble Nitrogen, and Free Alpha Amino Nitrogen contents of worts (the extract of malt used to make beer) and NIR transmission data using the multivariate method of partial least squares regression. The correlation coefficients, for both calibration and prediction data sets, were significant and the standard error of prediction was similar to that obtained in the standard methods in the first year, but were unsatisfactory in the second. The instrument chosen for the study gave satisfactory correlations for the purpose of selection in the intermediate generations of the breeding programme with errors similar to the analytical methods, as long as a very wide range of calibration samples were collected from more than one harvest. It was shown that the use of an NIR spectrophotometer as a selection tool for malting quality within a barley breeding programme would not be sufficient to justify investment in this type of instrument for this purpose alone.
23
Taylor, Helen Ruth. "The evaluation of wort by near infrared spectroscopy /." View thesis, 2001. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030717.141010/index.html.
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Thesis (M.Sc. (Hons.)) -- University of Western Sydney, 2001."A thesis submitted in partial fulfilment of the requirements for the degree of Master of Science (Honours), University of Western Sydney, Hawkesbury" Bibliography : leaves 60-66.
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Cowley, Richard D. "The clinical applications of near infrared spectroscopy (NIRS)." Thesis, University of Manchester, 2003. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488355.
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Samamad, Nancy Taera Ibraimo. "Cashew apple quality by near infrared spectroscopy technique." Universidade Federal de Viçosa, 2016. http://www.locus.ufv.br/handle/123456789/8350.
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O cajueiro (Anacardium occidentale L.) é uma planta de grande importância econômica para o Nordeste brasileiro, pela diversidade de produtos e quantidade de empregos gerados. A crescente demanda por produtos saudáveis associados ao aumento no consumo do caju de mesa incentivou o desenvolvimento de tecnologias para monitorar os critérios de qualidade. Esses critérios são determinados por meio de análises destrutivas, que são normalmente demoradas, com custos altos e não leva em consideração a variabilidade individual do caju. Visando substituir essas análises, a espectroscopia de infravermelho próximo (NIRS) permite a determinação simultânea e não destrutiva de vários atributos de qualidade. NIRS é uma técnica rápida que correlaciona as propriedades de absorção de energia em regiões do espectro electromagnético com a composição e concentração de moléculas através de modelos de regressão desenvolvidos por meio da quimiometria. O objetivo deste estudo foi desenvolver modelos preditivos em NIRS para o dispositivo de bancada e portátil visando estimar propriedades físico-químicas tais como firmeza, pH, sólidos solúveis totais (TSS), açúcares solúveis (SSC), acidez titulável (TA), sabor, ácido ascórbico (vitamina C), carotenóides, flavonóides totais, polifenóis extraíveis totais (TEP) e atividade antioxidante para o monitoramento da qualidade do pedúnculo de caju. Para o dispositivo de bancada, os modelos foram construídos com 34 amostras de 17 genótipos a partir de espectros coletados no modo de refletância. Os modelos preditivos obtidos para firmeza e pH apresentaram valores de coeficiente de determinação para validação cruzada (R2CV) de 0.92 e 0.84, respectivamente, enquanto que para os coeficientes de determinação para a validação externa (R2P) foram de 0.87 para firmeza e 0.78 para pH. A relação do desempenho do desvio para validação cruzada (RPDCV) apresentaram valores de 3.0 e 2.4 e, para a validação externa (RPDP) se obtiveram valores de 2.4 e 2.2 para firmeza e pH, respectivamente, indicando boa capacidade de predição. Para as variáveis do metabolismo primário, os valores obtidos para o R2CV foram de 0.86 para SSC, 0.83 para TSS, 0.90 para TA e de 0.80 para sabor, sendo que os valores de R2P foram de 0.78, 0.75, 0.85 e 0.73, respectivamente. Os valores apresentados para RPDCV foram, respectivamente, de 2.6, 2.4, 3.1 e 2.1 para SSC, TSS, TA e sabor, enquanto que os valores de RPDP foram de 2.0 para SSC e TSS, 3.0 para TA e 1.8 para sabor. No metabolismo secundário, foram obtidos modelos com valores de 0.87 para R2CV e de 0.85 R2P para vitamina C, apresentando boa capacidade de predição tanto para validação cruzada como para validação externa, com valores de RPDCV e de RPDP de 2.6 e 2.8. Para carotenoides, modelos com R2CV e R2P de 0.89 e 0.79 foram obtidos, com RPDCV e de RPDP 2.9 e 2.0, respectivamente, enquanto que para flavonóides totais, foram obtidos valores de 0.86 para ambos R2CV e R2P e, valores de RPDCV de 2.6 e de 2.0 para RPDP. Modelos obtidos para TEP tiveram valores 0.90 para R2CV e de 0.89 para R2P, bem como valores de RPDCV de 3.2 e 2.5 de RPDP, sendo que para atividade antioxidante foram obtidos modelos com valores de R2CV e R2P de 0.87 e de 0.81, respectivamente, com valores de RPDCV de 2.7 e 2.2 para RPDP. Para o dispositivo portátil, foram obtidos modelos preditivos de 75 amostras provenientes de 21 diferentes genótipos sendo que para firmeza, pH, TSS, TA, sabor e vitamina C os valores de R2CV foram de 0.77, 0.75, 0.90, 0.85, 0.80 e 0.89, respectivamente com a média do erro relativo de -1.1%, 0.2%, 0.5%, -1.3%, 2.6% e 4.9%. Para essas variáveis, foram obtidos valores de coeficientes de determinação para previsão (R2P) de 0.76, 0.72, 0.88, 0.85, 0.82 e 0.83 com os coeficientes de variabilidade do erro padrão de previsão (SEP) de 18.2%, 3.0%, 5.6%, 19.6%, 15.4% e 12.1%. Além destes, realizou-se um experimento de monitoramento de qualidade do caju de mesa refrigerado por NIRS ao longo de nove dias. Foram utilizados quatro genótipos com três repetições onde se avaliou TSS, vitamina C e pH analisados em parcelas subdividida no tempo.
The cashew tree (Anacardium occidentale L.) is a plant with great economic importance for the Brazilian Northeast, due to diversity of products and the amount of jobs generated. Growing demand for healthy products associated an increase in table cashew consumption encouraged the development of technologies to monitor quality criteria. These criteria are determined by destructive analyses, which are usually time-consuming, with high costs and do not take into account the individual cashew variability. Aiming to replace these analyses, the near-infrared spectroscopy (NIRS) allows simultaneous and nondestructive determination of multiple quality attributes. NIRS is a rapid technique that correlates the energy absorption properties in regions of the electromagnetic spectrum with the composition and concentration of molecules through regression models developed by chemometrics. The aim of this study was to develop predictive models in NIRS for bench top and portable device to estimate physical-chemical properties such as firmness, pH, total soluble solids (TSS), soluble sugars (SSC), titratable acidity (TA), flavor, ascorbic acid (vitamin C), carotenoids, total flavonoids, total extractable polyphenols (TEP) and antioxidant activity for monitoring cashew apple quality. For the bench device, the models were constructed with 34 genotypes of 17 samples collected from the reflectance spectra mode. The predictive models obtained for firmness and pH showed determination coefficient values for cross-validation (R2CV) of 0.92 and 0.84, respectively, while for external validation or prediction, coefficients of determination (R2P) were 0.87 for firmness and 0.78 for pH. The residual prediction deviation of cross-validation (RPDCV) have presented values of 3.0 e 2.4 and for external validation values of 2.4 and 2.2 were obtained for firmness and pH, respectively, indicating a good predictive ability. For variables of primary metabolism, the obtained values for R2CV were 0.86 for SSC, 0.83 for TSS, 0.90 for TA and 0.80 for flavor and the R2P values were respectively of 0.78, 0.75, 0.85 and 0.73. The presented RPDCV values were 2.6, 2.4, 3.1 and 2.1 for SSC, TSS, TA and flavor, while RPDP obtained values were 2.0 for SSC and TSS, 3.0 for TA and 1.8 for flavor. In secondary metabolism, models with 0.87 values for R2CV were obtained with R2P of 0.85 for vitamin C. These models presented good ability to predict both cross-validation and external validation with RPDCV and RPDP values of 2.6 and 2.8, respectively. Carotenoids models presented R2CV and R2P values of 0.89 and 0.79, with RPDCV and RPDP of 2.9 and 2.0, respectively, while for total flavonóides, models were obtained with values of 0.86 for both R2CV and R2P as well as RPDCV values of 2.6 and 2.0 to RPDP. Models obtained for TEP has presented values of 0.90 for R2CV and 0.89 to R2P and RPDCV values of 3.2 as well as 2.5 for RPDP. Antioxidant activity models were obtained with R2CV and R2P values of 0.87 and 0.81, respectively, and RPDCV values of 2.7 and 2.2 for RPDP. For portable device predictive models, 75 samples from 21 different genotypes were collected and evaluated of which firmness, pH, TSS, TA, flavor and vitamin C presented R2CV values of 0.77, 0.75, 0.90, 0.85, 0.80 and 0.89, respectively, with the average relative error of -1.1%, 0.2%, 0.5%, -1.3%, 2.6% and 4.9%. For these variables were obtained coefficients of determination values for prediction (R2P) of 0.76, 0.72, 0.88, 0.85, 0.82 and 0.83 with standard error of prediction (SEP) coefficient of variability of 18.2%, 3.0%, 5.6%, 19.6%, 15.4% and 12.1%. Besides these, a quality monitoring experiment in cold storage was evaluated by NIRS over nine days. Four genotypes were used with tree repetitions for TSS, vitamin C and pH assessment evaluated in split plot in time.
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Ranasinghe, Pathirajage Sanjeewa Rasika K. "Nocturnal hypoglycemic alarm based on near-infrared spectroscopy." Diss., University of Iowa, 2014. https://ir.uiowa.edu/etd/4731.
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Noninvasive glucose monitoring has been the subject of considerable research because of the high number of diabetes patients who must monitor their glucose levels daily by taking blood samples. Among methods being evaluated for possible use in this application, near-infrared (NIR) spectroscopy has received significant attention because of available glucose absorption bands that can be observed in the presence of the large aqueous background found in tissue spectra. The objective of the research presented here is to evaluate the potential for implementing a noninvasive nocturnal hypoglycemic alarm with NIR spectroscopy. Such an alarm would be used by a diabetic to detect potentially dangerous occurrences of hypoglycemia during sleep.
The approach used is to collect spectra continuously from the patient during the sleep period, followed by the application of pattern recognition methods to determine if a spectrum represents a blood glucose level that exceeds a hypoglycemic threshold. A reference spectrum is collected and a conventional finger-stick glucose concentration measurement is made at the start of the sleep period. The ratio is then taken of each subsequent spectrum to the collected reference, forming a differential spectrum corresponding to the signed difference in concentration relative to the reference. The identification of these differential spectra as "alarm" or "non-alarm" is performed with a classification model computed with piecewise linear discriminant analysis.
This methodology is initially tested with in vitro laboratory data that simulated the glucose excursions that occur during sleep. The performance of the hypoglycemic alarm methodology in the presence of varying levels of urea, glyceryl triacetate, and L-lactate as potential spectral interferents is tested. The robustness of the methodology with respect to time is also evaluated.
The thesis further discusses an experimental procedure to prepare tissue phantoms composed of two main proteins that exist in human skin tissue, keratin and collagen. A new methodology is developed to produce varying-thickness films that allowed the simulation of changes in the content of skin tissue proteins present within the optical path of the NIR measurement. The prepared films are incorporated into in vitro laboratory measurements in which varying levels of glucose, urea, keratin, and collagen are introduced in order to provide a test of the hypoglycemic alarm algorithm that simulates the spectral properties of human tissue.
Finally, the hypoglycemic alarm algorithm is tested with in vivo data collected with rat animal models. Data are presented for single-day experiments performed with anesthetized rats, as well as for multiple-day experiments conducted with awake rats. The results obtained from both the in vitro and in vivo studies confirm that if high-quality spectral data are attainable, the alarm methodology can work effectively to identify hypoglycemic events while exhibiting a low rate of false detections.
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Ding, Haibiao. "Application of near infrared spectroscopy in meat quality assessment /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21021296.
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Tang, Yung-kwan. "Application of near-infrared spectroscopy in food composition analysis /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1973766X.
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丁海標 and Haibiao Ding. "Application of near infrared spectroscopy in meat quality assessment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31238403.
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Balkenhol, Michelle Rose. "Visible and near infrared reflectance spectroscopy of irregular solids /." Thesis, Connect to this title online; UW restricted, 1992. http://hdl.handle.net/1773/8493.
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Sayita, Yusuf. "Classification Of Migraineurs Using Functional Near Infrared Spectroscopy Data." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614184/index.pdf.
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Classification of migraineur and healthy subjects using statistical pattern classifiers on functional Near Infrared Spectroscopy (NIRS) data is the main purpose of this study. Also a statistical comparison between trials that have different type of classifiers, classifier settings and feature sets is done. Features are extracted from raw light measurement data acquired with NIRS device, namely Niroxcope, during two separate previous studies, using Modified Beer-Lambert Law. After feature extraction, Naïve Bayes classifier and k Nearest Neighbor classifier are utilized with and with-out Principal Component Analysis in separate trials. Results obtained are compared within each other using statistical hypothesis tests namely Mc Nemar and Cochran Q.
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Esteve, Agelet Lidia. "Permeation studies of PVC pipes with near infrared spectroscopy." [Ames, Iowa : Iowa State University], 2006.
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Persson, Jan. "Stream monitoring using near-infrared spectroscopy of epilithic material." Licentiate thesis, Umeå : Ecology and Environmental Science, Umeå University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1154.
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Shadgan, Babak. "Monitoring of skeletal muscle ischemia using near infrared spectroscopy." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/32630.
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Early diagnosis of acute limb muscle ischemia (LMI) is essential in order to avoid serious, irreversible local and systemic complications resulting in loss of the limb or even death. To date, techniques for monitoring LMI are limited by lack of a feasible and reliable monitoring method. Purpose: The main purposes of this thesis were to examine the feasibility and convergent validity of conventional and wireless near infrared spectroscopy (NIRS) for continuous monitoring of skeletal muscle oxygenation and hemodynamics during transient and long-term LMI and to investigate the predictive value of NIRS-derived data for evaluation of limb muscle oxidative changes during tourniquet-induced LMI. Methods: Following a complete literature review (Chapter 2), forearm muscle oxygenation and hemodynamics were studied in 10 healthy subjects using wireless NIRS instrumentation during isometric muscle contraction and tourniquet-induced LMI (Chapter 3). In Chapter 4, changes in NIRS-derived leg muscle oxygenation and hemodynamics, in conjunction with muscle oxidative changes, following tourniquet-induced LMI were investigated in 17 patients undergoing surgery for ankle fracture. In Chapter 5, the effect of electromagnetic interference (EMI) from 3 commonly used surgical instruments on NIRS signals were investigated using a mathematical method of signal analysis. Results: Chapter 2: No validated monitoring method for early detection of acute LMI was revealed. Chapters 3-4: Wireless and conventional NIRS data were consistent with muscle ischemia and reperfusion. Chapter 4: An average of 43.2±14.6 minutes of tourniquet-induced ischemia led to a 172.3±145.7% (range: 10.7-363.3%) increase in muscle protein oxidation (P<0.0005). Changes in NIRS-derived muscle oxygenated and total-hemoglobin were both negatively correlated, while reoxygenation-rate was positively correlated (P<0.05) to muscle protein oxidation. Chapter 5: EMI from 3 OR instruments was found to have no effect on NIRS signals (P<0.01). Conclusions: NIRS is a feasible method for continuous monitoring of limb muscle oxygenation and hemodynamics during transient and long-term tourniquet-induced ischemia. Tourniquet-induced LMI of 21-74 minutes leads to oxidative muscle damage. A significant negative association between the extent of tourniquet-induced oxidative damage and changes in NIRS-derived local muscle oxygenated blood volume was found. EMI of commonly used orthopedic surgical instruments does not affect NIRS signals.
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Mayfield, Angela Raye. "Characterization of textile materials by near-infrared relectance spectroscopy." Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/8616.
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Molavi, Behnam. "Near infrared spectroscopy : novel signal processing methods and applications." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45353.
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Oxygen is a critical component in living organisms and its concentration in tissue is an important parameter indicative of tissue metabolism, level of activity and health condition. As a result, measuring oxygen concentration in the tissue is essential in many clinical and research applications. Near Infrared Spectroscopy (NIRS)
is a non invasive method of measuring tissue oxygenation using diffusion of light in the tissue. NIRS as a safe, non invasive and low cost monitoring technology has been used in a wide range of applications including monitoring muscle and
brain oxygenation, brain computer interface and rehabilitation. The motivation for this thesis has been to develop new signal processing methods and to investigate potential new applications for NIRS.
One major characteristic of NIRS is its sensitivity to movement of the target tissue during the measurement. The effects of movements, known as motion artifacts, have limited clinical applications of NIRS in ambulant patients as well as experimental applications of NIRS monitoring in areas such as exercise science and sports medicine. In this thesis, we present a new method of reducing the effect of motion artifacts on NIRS signal using Discrete Wavelet Transform (DWT).
One of the areas of application which can significantly benefit from reduction of motion artifacts is NIRS-based wearable sensors. In particular, a potential and unexplored application of NIRS is providing a monitoring method for people with bladder control problems, which occurs in a variety of conditions including spinal cord injury and stroke. We investigate the application of NIRS for detection of bladder filling to capacity using a wearable wireless monitoring sensor which can
be used to warn the subject once the bladder content reaches a predefined percentage
of the full capacity. NIRS can be used as a functional neuroimaging method to identify brain activations during practice of a motor/cognitive task. One important question in this field is how the activated brain areas are interconnected. We thus investigate the use of phase information in NIRS channels to identify cortical connections and in particular, show the applicability of this approach in identifying language network
in human infants.
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Manley, Marena. "Wheat hardness by near infrared (NIR) spectroscopy : new insights." Thesis, University of Plymouth, 1995. http://hdl.handle.net/10026.1/2542.
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The determination of wheat hardness by the evaluation of whole wheat grain would be of considerable value to the UK Milling Industry. Until now, accurate whole wheat grain hardness predictions by NIR spectroscopy have only been reported for North American wheats. By the evaluation of selected samples of UK and North American wheats this study showed that the prediction of whole wheat grain hardness by NTR spectroscopy depends only on the scattering properties of the sample and that there is no direct relationship with chemical composition. The scattering effect, in case of whole wheat grain reflectance and transmittance spectra, was found not to be multiplicative as in the case of ground wheat grain spectra. Empirical NIR spectroscopy calibrations are often performed without knowing what is measured or understanding the basis of the measurement. In other words the NIR spectrophotometer is often used as a "black box". Empirical calibrations were performed using three different software packages i.e. lnfrasoft International (ISI) Software, NIRSystems Spectral Analysis Software (NSAS) and UNSCRAMBLER. Successful NIR spectroscopy hardness measurements on ground wheat are based on light scattering. Separating the scattering effect from whole wheat grain spectra mathematically allowed predictions not significantly different to empirical calibrations, with the benefit of a theoretical explanation and fewer terms used. Although hardness predictions for whole wheat grain were not as accurate as in the case of ground wheat grain, it did prove to predict hardness with an acceptable accuracy with practical use as screening methods for grain trading. This study did not completely solve the problem of predicting whole wheat grain hardness by NIR spectroscopy, but new insights were provided which would hopefully encourage further work in this area and lead to a more complete fundamental understanding of the properties of whole wheat grain hardness using NIR spectroscopy.
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Lister, Susan Jane. "Determination of silage composition using near infrared reflectance spectroscopy." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260701.
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Yeung, Ken Shu Ying. "Near infrared spectroscopy technique for bioprocess monitoring and control." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286892.
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Germon, Timothy John. "The validation of cerebral near infrared spectroscopy in adults." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299334.
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Barker, Tom. "The military applications of near infrared spectroscopy in trauma." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6732/.
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This work examines tissue oxygenation (StO2), as measured by near infrared spectroscopy (NIRS), as tool for assessing trauma patients, with particular emphasis on its use in the deployed military environment. Resting StO2 values were examined and found to vary significantly between monitoring sites. Exercise was associated with a significant increase in StO2. Comparing the sensitivities of different NIRS monitoring sites in detecting simulated hypovolaemia, the forearm and deltoid were found be the most sensitive sites. The thenar eminence and brain were not sensitive to mild degrees of hypovolaemia. The administration of morphine was found to attenuate the StO2 response to hypovolaemia at all sites. In a porcine trauma model changes in StO2 recorded from both injured and uninjured muscle sites phase led those of base excess and lactate by 31–37 minutes, and demonstrate that injured monitoring sites can be used to accurately track patients’ response to resuscitation. In the deployed military setting NIRS was found to be a robust, easy to use technique for the initial assessment of patients. Although StO2 was not demonstrable superior to a combination of pulse rate and blood pressure it has several practical advantages that make it a useful adjunct to contemporary trauma care.
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Klesman, Alison J. (Alison June) 1981. "Comet-asteroid differentiation using visible and near-infrared spectroscopy." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28610.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2004.Includes bibliographical references (leaves 40-42).
Comets have historically been defined as objects that experience the formation of a "head" (coma) or "tail" as ice and other volatiles that comprise their chemical makeup vaporize when they near the sun. Comets can lose this ability to form a coma or tail, however, through a variety of dynamical processes, creating objects that could chemically be comets but that do not fit the traditional definition. Thus, a new challenge has arisen to correctly define the properties that differentiate comets and asteroids. In this study, a number of cometary candidates were observed in visible and infrared wavelengths in an attempt to correctly classify them as asteroids or dormant or extinct comets. From this data, two groups of objects were identified: one group of possible cometary candidates, and one group of likely outer asteroid belt origin objects. From this and other studies, a broader picture of solar system dynamics can be achieved that will give much insight into not only the current dynamical processes that control interplanetary bodies, but also processes that were important in the formation and stratification of the solar system at its birth.
by Alison J. Klesman.
S.M.
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Alfeeli, Bassam. "Miniature gas sensing device based on near-infrared spectroscopy." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/35911.
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The identification and quantification of atoms, molecules, or ions concentrations in gaseous samples are in great demand for medical, environmental, industrial, law enforcement and national security applications. These applications require in situ, high-resolution, non-destructive, sensitive, miniature, inexpensive, rapid detection, remotely accessed, real time and continuously operating chemical sensing devices. The aim of this work is to design a miniature optical sensing device that is capable of detecting and measuring chemical species, compatible with being integrated into a large variety of monitoring systems, and durable enough to be used under extreme conditions.
The miniature optical sensor has been realized by employing technologies from the optical communication industry and spectroscopic methods and techniques. Fused silica capillary tubing along with standard communication optical fibers have been utilized to make miniature gas sensor based on near-infrared spectroscopy for acetylene gas detection.
In this work, the basic principles of infrared spectroscopy are reviewed. Also, the principle of operation, fabrication, testing, and analysis of the proposed sensor are discussed in details.Master of Science
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Kopicky, Stephen Edward. "The Use of Near Infrared Spectroscopy in Rubber Quantification." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1406122474.
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Montes, Juan Manuel. "Application of near-infrared spectroscopy in plant breeding programs." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:100-opus-1735.
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Wetterlind, Johanna. "Improved farm soil mapping using near infrared reflection spectroscopy." Uppsala : Dept. of Soil and Environment, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200968.pdf.
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Howell, Ellen Susanna. "Probing asteroid composition using visible and near-infrared spectroscopy." Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187372.
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The compositional distribution of asteroids provides clues to understanding solar system formation and evolutionary processes in the asteroid belt. The surface mineralogy and distribution of volatiles on asteroids is determined using visible and near-infrared spectroscopy. A revised asteroid taxonomy is developed which incorporates compositional information from the near-infrared asteroid spectra. A search is conducted for organic compounds on distant asteroids, thought to be most volatile-rich in composition. Our near-infrared spectroscopy of outer belt asteroids shows a trend of increasing red continuum slope with heliocentric distance. I interpret this trend as a compositional change, possibly due to increasing abundance of complex organic compounds on these more distant objects. I do not observe a CN absorption band near 2.2 $\mu$m, and conclude that the organics present are not primarily CN-bearing solids. The 3-$\mu$m water absorption band is not detected on distant D asteroids, but is seen on main belt D asteroids. This observation is consistent with the idea that D asteroids are volatile-rich, but the object must be heated in order to transform the silicates into hydrated minerals. No evidence of clay minerals is seen on any of the distant asteroids observed. The majority of the Jupiter Trojan asteroids have a uniform spectral appearance in spite of collisional processing, which implies that the dark red surface material is not a thin surface coating, but is representative of the bulk composition. Observations of near-Earth asteroids indicates a wide range of compositions, suggesting a variety of source regions. Two objects are detected which may contain hydrated minerals, a valuable resource in space. Three near-Earth asteroids are studied in detail, revealing a range of pyroxene chemistry and olivine content inconsistent with ordinary chondrite composition. The occurrence of spectral variability, and implied compositional inhomogeneity is approximately 20%, and on spatial scales as small as tens of meters. This observation implies that asteroids are geologically complex, not chemically uniform, as is often assumed in meteorite studies.
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BOBBA, SERENA. "Near-Infrared Spectroscopy for Freeze-Drying: Applications for Pharmaceuticals." Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2957736.
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Mayes, David M. "Applications of a photodiode array spectrophotometer for the short wavelength near-infrared region (700-1100 nm) /." Thesis, Connect to this title online; UW restricted, 1990. http://hdl.handle.net/1773/11567.
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Öztürk, Betül Özerdem Durmuş. "Monitoring the esterification reactions of carboxylic acids with alcohols using near-infrared spectrocopy and multivariate calibration methods/." [s.l.]: [s.n.], 2003. http://library.iyte.edu.tr/tezler/master/kimya/T000277.pdf.
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