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Development of NIR spectroscopy models for starch content prediction and ethanol production from mutant grain sorghumSaul, Kaelin E. January 1900 (has links)
Master of Science / Biological & Agricultural Engineering / Donghai Wang / The growing demands for renewable energy sources have led researchers to investigate other biomass sources, aside from maize. Grain sorghum is comparable to maize in its starch content and can be grown in regions with drier climates, where maize is a less suitable crop for these areas. In attempts to increase yield prior to harvest and for ethanol production, this study focuses on mutant grain sorghum. One hundred and nine mutant grain sorghum samples were analyzed for their chemical and physical properties and fermented into ethanol. The current method for starch analysis is time-consuming and tedious. Near infrared spectroscopy (NIR) models were developed as fast, cost-effective, and non-destructive methods for grain sorghum starch content analysis. Each mutated grain sorghum sample was scanned in a wavelength range from 4,000 to 10,000 cmˉ¹ as a whole grain and in flour form. Partial Least Squares (PLS) regression method was used for NIR model development. The coefficients of determination (R²) of 0.77 and 0.90 were achieved for starch content calibration and prediction models, respectively. This model demonstrates the possibility of a positive correlation between the actual and calculated values for starch content. Another PLS first derivative model with R² = 0.95 for calibration and a reduced wavelength range (4,000-5,176 cmˉ¹), using 39 of the original 109 samples (27 for calibration and 8 for validation), was created to predict the fermentation efficiency.
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Desenvolvimento de um analisador de processo por espectroscopia no infravermelho próximo (NIR) para previsão de propriedades de derivados de petróleo / Development of a near-infrared process analyzer for the prediction of properties of petroleum productsBueno, Aerenton Ferreira 18 August 2018 (has links)
Orientador: Célio Pasquini / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-18T09:40:06Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: O trabalho trata do desenvolvimento de um analisador de processo utilizando a espectroscopia no infravermelho próximo (NIR) para prever propriedades de derivados de petróleo, como gasolina e querosene de aviação. O instrumento foi projetado para ser instalado diretamente em uma linha de processo numa unidade industrial, realizando, de maneira automatizada, a coleta, análise e descarte da amostra, envio dos resultados obtidos, além de operações como limpeza da célula e diagnósticos funcionais. Um protótipo de um espectrofotômetro NIR de bancada foi construído, a partir do qual, foi montado um espectrofotômetro de laboratório plenamente funcional. O espectrofotômetro foi instalado num gabinete com sistema de pressurização (para estar de acordo com a classificação da área industrial), controlador de temperatura e dispositivos para a seleção da amostra e limpeza da célula, tornando-se, assim, um analisador de processo. Um programa de computador em linguagem Visual Basic foi desenvolvido para a operação automatizada do analisador. Foram obtidos espectros e desenvolvidos modelos de calibração multivariados para prever uma série de parâmetros de qualidade de gasolina (como destilação, octanagem e concentrações de aromáticos, olefinas e saturados) e querosene de aviação (massa específica e ponto de congelamento), que apresentaram resultados compatíveis com os valores de precisão dos métodos de referência utilizados. O analisador foi instalado num sistema de mistura para produção de gasolina de uma refinaria de petróleo, visando prever, em tempo real, vários parâmetros de qualidade desse produto, para a otimização do processo produtivo / Abstract: The work deals with the development of a process analyzer using near infrared spectroscopy (NIR) to predict properties of petroleum products like gasoline and jet fuel. The instrument was designed to be mounted directly on a line in an industrial process, performing automatically the collection, analysis and disposal of the sample, transmission of results, as well as operations such as cleaning the cell and functional diagnosis. A prototype of a benchtop NIR spectrometer was built, from which a fully functional laboratory spectrophotometer was assembled. The spectrophotometer was installed in a cabinet with a pressurization system (to be consistent with the classification of the industrial area), temperature controller and devices for sample selection and cleaning of the cell, becoming thus a process analyzer. A computer program written in Visual Basic was developed for the automated operation of the analyzer. Spectra were acquired and multivariate calibration models were developed to predict a series of gasoline (such as distillation, octane and concentrations of aromatics, olefins and saturated) and jet fuel quality parameters (specific gravity and freezing point), who presented results compatible with the precision values of the reference methods used. The analyzer was installed in a blending system for production of gasoline in an oil refinery, aimed to provide, in real time, various quality parameters of the product, to optimize the production process / Doutorado / Quimica Analitica / Doutor em Ciências
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Determinação dos parametros de qualidade de detergentes em po utilizando espectroscopia no infravermelho proximo / Determination of the parameters of quality of powder detergents using near infrared spectroscopyPovia, Giovana Soato 30 May 2007 (has links)
Orientador: Celio Pasquini / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-09T09:59:17Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: Este trabalho visa o desenvolvimento de um método analítico para a determinação dos parâmetros de qualidade em detergentes em pó utilizando a Espectroscopia de Infravermelho Próximo (NIR) e técnicas de calibração multivariada. Foram utilizados dois conjuntos de amostras: o primeiro para as análises quantitativas e o segundo para análises qualitativas. As amostras do primeiro conjunto tiveram os parâmetros de qualidade determinados pelos respectivos métodos de referência. A técnica estatística utilizada para as calibrações foi o PLS. Foram desenvolvidos modelos de calibrações para a previsão do teor de umidade, matéria ativa e densidade. O desempenho dos modelos de calibrações foi avaliado por meio de validação externa. A determinação do teor de umidade apresentou RMSEP = 0,29% (m/m). O valor de RMSEP para a determinação da matéria ativa foi de 0,37% (m/m) e para a determinação da densidade o valor de RMSEP = 14 g L . Os modelos construídos apresentaram resultados satisfatórios e os erros encontrados são aceitáveis para a faixa de controle utilizada na indústria. O segundo conjunto é composto de 4 grupos, que apresentam características distintas. Foram avaliados dois métodos de classificação: SIMCA e PLS DA. É possível observar que ocorre a discriminação das amostras que apresentam teor de matéria ativa mais elevado, no entanto, os outros grupos não puderam ser discriminados. Os dois métodos de classificação avaliados apresentaram resultados semelhantes, com acerto de 100% na classificação de amostras externas somente em seus respectivos grupos / Abstract: This work aims the development of an analytical method for the determination of quality parameters on powder detergents using the near infrared spectroscopy (NIR) and multivariate calibration techniques. Two sets of samples were used: the first one for the quantitative analysis and the second one for qualitative analysis. The samples of the first set had the quality parameters determined by their respective methods of reference. The chemometric technique used for calibration was the PLS1. Calibrations for the prediction of de moisture content, active matter and density were developed. The performance of the calibration models was evaluated through external validation. The determination of the moisture content presented a RMSEP = 0,29% (w/w). The value of RMSEP for the determination of the active matter was 0,37% (w/w) and for the determination of moisture the value of RMSEP was 14 g L. The constructed models presented satisfactory results and the errors that were found are acceptable for the control range used in industry. The second set is composed of four groups of power detergents which present different characteristics. Two methods of classification were evaluated: SIMCA and PLS DA. It was possible to observe the discrimination of the samples which presents higher active matter content. However, the other groups could not be discriminated. Both methods of classifications evaluated presented similar results, with 100% correcte results of the classification of samples only in their respective groups / Mestrado / Quimica Analitica / Mestre em Química
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Espectroscopia de infravermelho-próximo em madeiras neotropicais: aplicação na identificação e predição de propriedades físicas / Near-infrared spectroscopy in neotropical woods: application to identification and prediction of physical propertiesRaphael Jaquier Bossler Pigozzo 06 May 2011 (has links)
A madeira é uma excelente matéria-prima renovável, sendo empregada como fonte de celulose e na construção civil, e sendo usada ainda como combustível. Contudo, as propriedades da madeira variam muito entre as espécies. Logo, saber a qual espécie pertence a madeira, assim como algumas de suas propriedades é essencial para um planejamento adequado de sua aplicação, evitando desperdícios e melhorando a qualidade dos produtos derivados do material. No presente estudo, analisou-se a aplicação da espectroscopia de infravermelho-próximo (NIR) na identificação e predição de propriedades físicas de madeiras nativas ou plantadas no Brasil, as quais apresentam grande variação entre suas propriedades e características anatômicas. Primeiramente, foi verificada a relação do espectro NIR com a densidade básica e algumas das características anatômicas importantes para identificação de madeiras, em especial aquelas ligadas aos raios parênquimáticos. Em seguida, com a espectroscopia NIR, foram desenvolvidos modelos para predição da densidade básica em madeiras de várias espécies brasileiras. Por fim, aplicou-se a espectroscopia NIR para discriminação entre as madeiras de Dalbergia nigra e D. spruceana, as quais são muito semelhantes em aspecto e características anatômicas. Os resultados sugerem que a espectroscopia de infravermelho-próximo é uma potencial ferramenta para classificação das diferentes madeiras brasileiras de acordo com suas propriedades físicas. Os resultados sugerem ainda uma metodologia auxiliar no processo de identificação pela anatomia do lenho. / Wood is an excellent renewable raw material, used as fuel, pulp and as building material. However, the properties of wood vary widely among species. Therefore, knowing the wood species as well as some of its properties is essential for proper planning of its application, avoiding waste and improving the quality of wood based products. In this study it was analysed the application of the near infrared spectroscopy (NIR) to identification and prediction of physical properties of native or planted timbers from Brazil, which show great variation on their properties and anatomical features. First, it was verified the relationship between the NIR spectrum and the basic density as well as some important anatomical features for wood identification, especially those related to ray parenchyma. Then, using NIR spectroscopy, models were developed to predict the wood basic density from various Brazilian species. It was also applied NIR spectroscopy to separate the woods from Dalbergia nigra and D. spruceana, two woods that are very similar in appearance and anatomical features. The results suggest that near-infrared spectroscopy is a potential tool for classification of various Brazilian woods based on their physical properties, as well as an auxiliary method in wood anatomy identification.
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Estratégias quimiométricas aplicadas ao estudo de imagens químicas : novas possibilidades para caracterização de produtos e processos farmacêuticos / Chemometric strategies applied to the study of chemical imaging : new possibilities for the characterization of pharmaceutical products and processesSabin, Guilherme Post, 1977- 03 November 2013 (has links)
Orientador: Ronei Jesus Poppi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-22T17:44:22Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: A indústria farmacêutica está em constante busca por novas tecnologias analíticas capazes de fornecer informações relevantes sobre produtos e processos industriais. Esta tese sugere novas possibilidades no estudo de medicamentos através de imagens químicas obtidas por microespectroscopia na região do infravermelho próximo e as seguintes ferramentas quimiométricas: MLR, CLS, MCR e PLS. Os trabalhos estão divididos em quatro tópicos e contribuem para o avanço analítico neste campo de conhecimento. Na primeira aplicação, foi realizado um estudo da similaridade entre imagens obtidas por técnicas quimiométricas distintas. O trabalho mostra como estimar limites de confiabilidade para a concentração por pixel de imagem. Assim, foi possível diminuir o tempo de aquisição de imagens mantendo a confiabilidade analítica no estudo de comprimidos de carbamazepina. O segundo estudo mostra uma aplicação onde a vantagem de segunda ordem foi requerida. Este estudo traz uma abordagem nova sobre o reconhecimento de padrões de imagem na caracterização de produtos farmacêuticos. Na terceira aplicação, o objetivo foi acompanhar o desenvolvimento industrial de um produto farmacêutico com baixo teor de ativo, auxiliando no processo de decisão em termos de micro-homogeneidade da formulação. O estudo mostrou que a concentração local pode ser explorada como vantagem analítica. Na quarta aplicação, foi abordado pela primeira vez na literatura, o estudo da estrutura de pellets farmacêuticos através de informações químicas obtidas por espectroscopia de imagem química na região do infravermelho próximo. Este trabalho abre alternativas para o estudo de medicamentos de entrega controlada. / Abstract: The pharmaceutical industry is constantly searching for new analytical technologies capable of providing relevant information about products and industrial processes. This thesis suggests new possibilities in the study of drugs by using chemical images obtained by microspectroscopy in the near infrared region and the following chemometric tools: MLR, CLS, MCR e PLS. The work is divided into four topics and it contributes to the advancement in the field of analytical knowledge. In the first application, a study was performed about the similarity between images obtained by different chemometric techniques. The work demonstrates how to estimate concentration reliability limits per image pixel. Thus, it was possible to shorten the time of image acquisition while maintaining analytical reliability in the study of carbamazepine tablets. The second study presents an application where the advantage of the second order was required. This study presents a new approach to the recognition of image patterns in the characterization of pharmaceuticals. In the third application, the aim was to follow the industrial development of a pharmaceutical product with a low active content, assisting in the decision about the process in terms of micro-homogeneity of the formulation. The study showed that the local concentration can be exploited for analytical advantage. In the fourth application, addressed in a publication for the first time, is the study of the structure of pharmaceutical pellets through chemical information obtained by near infrared chemical imaging. This work opens up alternatives for the study of controlled delivery drugs. / Doutorado / Quimica Analitica / Doutor em Ciências
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Consistency of near-infrared spectroscopy chromophores during a 10-minute vascular occlusion procedure of the thigh over 5 consecutive daysMackintosh, Cameron Eve 07 July 2016 (has links)
The purpose of this study was to examine the consistency of near-infrared spectroscopy (NIRS) measures associated with a 10 minute vascular occlusion of the thigh during 5 consecutive days. A secondary purpose was to examine if the repeated daily occlusions modify the vascular response to such occlusions. The NIRS chromophores of oxygenated hemoglobin (HbO2), deoxygenated hemoglobin (HHb), total hemoglobin (tHb), hemoglobin difference (HbDiff), and total saturation index (TSI) were monitored at the vastus lateralis muscle during each testing session. Participants were female (age 18-30 yrs) and were randomly assigned to one of two groups. The Test Group (age 23 ± 2yrs) completed an occlusion test every day for 5 consecutive days while the Control Group (age 21 ±1.6yrs) was tested on days 1, 3 and 5. Each testing session involved 10 minutes rest in a supine position, 10 minutes of femoral artery occlusion (preset at 250mmHg), 10 minutes of recovery. At onset of occlusion, the rapid cuff inflation system inflated in 0.3 seconds to the preset 250mmHg. Following the 10 minutes of occlusion, the cuff was deflated in 0.3 seconds. Heart rate was monitored throughout all testing sessions and mean arterial pressure was calculated and compared between groups.
There were no significant group or day main effects found, nor any significant interactions for the following hemoglobin chromophores measures: HbO2, HHb, HbDiff, and TSI. In all participants, the NIRS response pattern to rest, occlusion and recovery was consistent for all testing days regardless of group. The response pattern to the occlusion initiated by the rapid cuff inflation was as follows: HbO2, tHb, HbDiff, and TSI decreased then slowly plateaued over the 10 minutes while HHb increased initially and then plateaued. Following the rapid cuff deflation, HbO2, tHb, HbDiff and TSI increased to their maximum reperfusion levels and then plateaued over the remainder of the 10 minutes of recovery. During that same period, HHb decreased initially upon reperfusion and then plateaued. Unlike the other measures, TSI and tHb demonstrated inconsistencies in their response pattern regardless of group or day.
The consistency of hemoglobin chromophores response pattern to daily 10 minute vascular leg occlusions over 5 consecutive days is an important finding of this study. This response indicates that there is no apparent change in vascular response to repeated occlusions and has implications for exercise studies that use occlusion in their methodology. The study also emphasizes the inconsistency of tHb and TSI as primary hemoglobin response measures to occlusion. Similarly, the results demonstrate the potential misinterpretation of results if only relying on one hemoglobin measure during occlusion. / Graduate
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Use of near-infrared spectroscopy to identify trends in regional cerebral oxygen saturation in horsesMcConnell, Emma Jane January 2013 (has links)
This dissertation focuses on the use of near-infrared spectroscopy (NIRS) to identify trends in regional cerebral oxygen saturation (rSO2) in both conscious and anaesthetised healthy horses.
A cerebral/somatic oximeter sensor recorded rSO2 from the dorsal sagittal sinus of 6 healthy horses. Values for rSO2, arterial and venous oxygen and carbon dioxide tensions (PaO2, PvO2, PaCO2 and PvCO2 respectively), along with arteriovenous oxygen saturations (SavO2) were recorded in unsedated (recording period [RP] 1), sedated (RP2), and anaesthetised horses (RP3-5); and during recovery (RP6-8). During anaesthesia, horses were ventilated to achieve states of normo- (RP3), hyper- (RP4) and hypocapnoea (RP5).
Overall mean ± s.d. values for rSO2, PaO2, PvO2, PaCO2, SavO2 and mean arterial pressure (MAP) varied significantly by RP. Significant decreases in rSO2 were identified between RP1 and the post-anaesthetic periods however no significant differences in rSO2 values were identified between RP1 and the intra-anaesthesia periods. Regional cerebral oxygen saturation was significantly correlated with PaO2, PvO2 and SavO2. No correlation was identified between rSO2 and lactate concentration.
This is the first study to identify trends in rSO2 in horses using NIRS. A significant positive correlation was identified between rSO2 and PvO2, suggesting that alterations in cerebral oxygenation may be reflected in jugular PvO2. Results of this study demonstrate that NIRS can be used during general anaesthesia to monitor trends in rSO2 in healthy horses, and has the potential to alert clinicians to cerebral desaturation events when used in a clinical setting. / Dissertation (MMedVet)--University of Pretoria, 2013. / gm2014 / Companion Animal Clinical Studies / unrestricted
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Quantitative evaluation of starch determination in feed samples using Near Infra-red ReflectanceMapekula, Nwabisa Nolwazi. January 2012 (has links)
In an attempt to reduce the costs and turn around times experienced with outsourcing starch analysis in finished feed products, the company decided to invest in a NIR instrument to carry out such analyses in house. The particular instrument purchased by the company comes with a build in calibration for specific finished feed products and the main objective of this investigation was to evaluate whether the instrumentation and build in calibration gives reliable analyses of a finished poultry feed. The results obtained showed that : - The NIR results obtained have a positive bias compared to the theoretical (formulation specified value) and also to the value obtained by enzymatic starch analysis. - Despite the positive bias, the starch values were well within the allowable limits - Repeatability measurements on the data generated by two different analysts showed that while the percentage relative standard deviations obtained (< 1.0 percent) were well within the company specifications of percentage RSD < 5.0 percent, the inter sample repeatability showed small, but significant variation. - The results for intermediate precision showed that there is no statistically significant difference between the results obtained by two different analysts, nor was there any difference in the results of the same samples analysed at different time periods. - Reproducibility could not be evaluated due to the lack of another instrument within the company that were similarly set up as the instrument used for the investigation. This investigation has shown that, given the restrictions enforced by the build incalibration of the NIR instrument, the use of NIR for the analyses of the finished feed product is valid, but will require that careful attention be paid to data collection procedures.
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Temporal Mapping and Connectivity using NIRS for Language Related TasksHall, Michael A 09 February 2012 (has links)
Near infrared spectroscopy (NIRS) is an emerging neuroimaging modality with high temporal and good spatial resolution. In this thesis, NIRS was applied to understand functionality of the fronto-temporal cortex in response to language-related tasks. A 32-channel NIRS system (Imagent ISS Inc.) was used to perform experimental studies on 15 right-handed normal adults. Block-design based Word Expression and Word Reception paradigms were independently presented to participants. Activation, functional connectivity and cortical lateralization analyses were performed. From word expression studies, results showed left anterior region (encompassing Broca) is majorly involved over right homologue and posterior regions. From the word reception studies, results showed that right posterior region (encompassing right homologue of Wernicke) is highly involved in language reception, with right anterior region (encompassing right homologue of Broca) also involved. The current study has potential future applications in surgical evaluation of language regions in populations with neurological disorders such as epilepsy, and schizophrenia.
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Evaluating motion processing algorithms for use with fNIRS data from young childrenDelgado Reyes, Lourdes Marielle 01 December 2015 (has links)
Motion artifacts are often a significant component of the measured signal in functional near-infrared spectroscopy (fNIRS) experiments. A variety of methods have been proposed to address this issue, including principal component analyses (PCA), Kalman filtering, correlation-based signal improvement (CBSI), wavelet filtering, spline interpolation, and autoregressive algorithms. The efficacy of these techniques has been compared using simulated data; however, our understanding of how these techniques fare when dealing with task-based cognitive data is limited. Recently, Brigadoi et al. (2014) quantitatively compared 6 motion correction techniques in a sample of adult data measured during a simple cognitive task. Wavelet filtering showed the most promise as an optimal technique for motion correction. Because fNIRS is often used with infants and young children, it is critical to evaluate the effectiveness of motion correction techniques directly with data from these age groups. Here we examined which techniques are most effective with data from young children. The efficacy of each technique was compared quantitatively using objective metrics related to the physiological properties of the hemodynamic response using two different sets of parameters to ensure maximum retention of included trials. Results showed that targeted PCA (tPCA) and CBSI retained a higher number of trials. These techniques also performed well in direct head-to-head comparisons with the other approaches using both quantitative metrics and a qualitative assessment. The CBSI technique corrected many of the artifacts present in our data; however, this technique was highly influenced by the parameters used to detect motion. The tPCA technique, by contrast, was robust across changes in parameters while also performing well across all comparison metrics. We conclude, therefore, that tPCA is an effective technique for the correction of motion artifacts in fNIRS data from young children.
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