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1
Nybacka, Louise. "FTIR spectroscopy of glucose." Thesis, Uppsala universitet, Fasta tillståndets elektronik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-306952.
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Approximately 450 000 people have diabetes in Sweden today, and the number of diabetics only rises. Monitoring blood sugar several times a day is a fundamental part of managing the disease, and reducing the risks of complications. Today’s glucose monitoring devices are invasive and require small needle sticks for a measurement. Providing a painless method of monitoring the blood sugar level would relieve the lives of diabetics world-wide. The objective of this project was to investigate the absorption spectra of aqueous glucose concentrations (100 to 5000 mg/dl) in the mid infrared region with Fourier Transform spectroscopy (FTIR), and finally implementing a hand-held monochromatic spectrometer to demonstrate a non-invasive concept. The method chosen for implementing the hand-held demo is due to the commercial availability of diodes and detectors at those wavelengths. The results from the FTIR showed a trend among concentrations in all wavelengths, in between 1180 to 980 cm-1, specifically at 1035 cm-1, but also in the region 2920 to 2850 cm-1. The hand-held spectrometer did not register any transmittance of the glucose samples. For future implementations, 1035 cm-1 should be investigated more in-depth for a hand-held device.
2
Finch, D. C. "FTIR spectroscopy of electron irradiated polymers." Thesis, Brunel University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381899.
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Baisitse, Tshepiso Revonia. "Characterisation of InAs-based epilayers by FTIR spectroscopy." Thesis, Nelson Mandela Metropolitan University, 2007. http://hdl.handle.net/10948/474.
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This study focuses on the characterization of InAs and InAs1-xSbx epitaxial layers by infrared reflectance and transmittance spectroscopy and Hall measurements. Reflectance measurements were performed in order to obtain the dielectric parameters and to extract from these information about the electrical properties (mobility and carrier concentration) of this important III-V material system. The transmittance measurements were used to determine the bandgap of InAsSb. Infrared reflectivity and transmittance measurements were performed in the wavelength range 200 – 2000 cm-1 on InAs and InAsSb layers grown on three types of substrates. A classical two oscillator model that takes into account both the free carriers and the lattice, was used to analyse the reflectance data using the BMDP® computer curve fitting software. The dielectric parameters and the electrical properties (carrier concentration and mobility) were extracted from the simulations. Due to the low free carrier concentration in the epitaxial structures, the plasma resonance frequency (ωp) values obtained from the simulations of reflectance spectra measured above 200 cm-1, were in the order of 20-30 cm-1. These low values were confirmed by direct measurements of ωp in reflectance spectra obtained in the range 15-200 cm-1. The simulated carrier concentration and mobility values determined optically were compared to the values determined by Hall measurements at room temperature and previously reported values by other researchers. The simulated values obtained were in reasonable agreement with the Hall values. The simulated and measured carrier concentrations obtained for InAs layers were significantly higher than the intrinsic carrier concentration for InAs at room temperature, indicating notable concentrations of donors resulting from the growth process.
4
Becker, Edo. "FTIR-Emissionsspektroskopische Untersuchungen der arktischen Atmosphäre = Investigations of the arctic atmosphere by FTIR-Emission spectroscopy /." Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1998. http://www.gbv.de/dms/bs/toc/247022616.pdf.
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Memon, Khalida Perveen. "Solid fat index determination by Fourier transform (FTIR) spectroscopy." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=24028.
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This work describes an investigation of the development of a Fourier Transform Infrared (FTIR) spectroscopic method for the determination of Solid Fat Index (SFI) of fats as a possible replacement of the traditional dilatometric procedure. The initial approach considered was the use of an existing FTIR analytical package which was designed to measure iodine value (IV), saponification number (SN), and cis and trans content. It was hypothesized that these measures could be related to SFI using multiple linear regression (MLR), thereby allowing the existing analytical package to simultaneously make SFI measures. It was found that there was a strong relationship between SN/cis/trans measurements and SFI, especially in sequentially hydrogenated oils. The MLR relationships, however, did not reproduce the dilatometric SFI values with sufficient accuracy in the general case, and this approach had to be abandoned. Subsequently, a partial least squares (PLS) calibration approach was investigated, relating the dilatometric SFI data directly to the spectral characteristics of the melted fats. It was found that suitable PLS calibrations could be developed for soybean and Canola oils. Based on these results, an FTIR system was programmed to determine SFI and the performance of the system validated using pre-analyzed "unknowns". It was shown that the SFI of either soybean or Canola oils could be determined to within $ pm$ 1.0 SFI. As configured, the FTIR system is capable of determining the SFI of a neat and clear, melted fat sample at 80$ sp circ$C in less than two minutes, providing four SFI values, representing the solids content at 50, 70, 80 and 92$ sp circ$F. In contrast to the standard dilatometric method, which takes over two hours to carry out, the FTIR approach provides a rapid means of determining SFI, the technique being suitable for routine quality control applications in the fats and oils industry.
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Garip, Sebnem. "The Characterization Of Bacteria With Fourier Transform Infrared(ftir) Spectroscopy." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606673/index.pdf.
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New and rapid techniques for the characterization and identification of
bacteria would have an important role in clinical microbiology and in food
analysis because of an increasing prevalence of infectious diseases and
In this work we carried out two approaches. In the first study the
characterization and differentiation of mesophilic and thermophilic
bacteria were investigated by using Fourier Transform Infrared (FTIR)
Spectroscopic technique. In the second study, we investigated the
characterization and identification of 3 Bacillus and Micrococcus species
Our results from first approach show that there was a dramatic
difference between mesophilic and thermophilic bacteria. The protein
concentration was high, lipid concentration, the level of triglycerides and the unsaturated acyl chains decreased in thermophilic bacteria. We
found that in thermophilic bacteria PO-
2 groups become hydrogen
bounded. In addition, our results suggest that the cellular DNA content
was low in thermophilic bacteria.
Moreover there were characteristic peaks for both mesophilic and
thermophilic bacteria and these peaks can be used for the differentiation
of these two bacteria group. There were also some specific peaks that
can be used for the differentiation of Escherichia coli and Lactobacillus
plantarum at species level.
In the second approach, our results show that there were significant
spectral differences between Bacillus and Micrococcus species such as
the proportion of unsaturated acyl chains in triglycerides were higher in
Micrococcus species. Moreover we observed different bands that may
be explained by an acetate oxidation via the tricarboxylic acid cycle and
an exopolymer formation in Micrococcus species. In addition to that
another band similar to glycogen, may be explained by a glycogen-like
storage material in Micrococcus species. Also there are characteristic
peaks that can be used for identification of Micrococcus spp.
7
Crowley, J. N. "A study of reaction mechanism by matrix isolation / FTIR spectroscopy." Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378892.
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LUZ, ELAINE ROCHA DA. "PREDICTION OF PROPERTIES OF GASOLINE USING FTIR SPECTROSCOPY AND PLS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4432@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORDiversas propriedades físico-químicas de gasolinas (teores de álcool, benzeno, aromáticos, saturados e olefinas, densidade, MON, RON e temperaturas de destilação) foram estimadas simultaneamente por espectroscopia na região do infravermelho médio (FTIR) acoplada à regressão por mínimos quadrados parciais (PLS). Os métodos de referência utilizados incluíram métodos ASTM, ABNT e o equipamento IROX, baseado em espectroscopia na região do infravermelho próximo. Embora o erro médio da predição (RMSEP) tenha sido o principal parâmetro considerado para selecionar o melhor modelo de predição para cada propriedade, a repetibilidade e a reprodutibilidade também foram avaliados. As propriedades que tiveram como método de referência o equipamento IROX (todos os teores, MON e RON) apresentaram, em geral, resultados mais pobres, sendo o pior resultado o encontrado para o teor de olefinas (21,3 +- 2,4) e o melhor para MON (82,5 +- 0,5). No caso das propriedades que tiveram como referência métodos ASTM ou ABNT (teor de álcool, densidade e temperaturas de destilação) o pior resultado encontrado foi para o teor de álcool (23,9 +- 0,7) e o melhor para a densidade (0,7556 +- 0,0025). No entanto, mesmo quando os valores de RMSEP encontrados através da regressão PLS foram considerados pequenos, os coeficientes de correlação (R2) entre os valores preditos e os de referência, para um conjunto de amostras independentes da calibração, foram menores que 0,70, para todas as propriedades. Isso se deve, principalmente, a pouca variação nos valores de algumas propriedades, como MON, por exemplo, que em todas as gasolinas analisadas apresentou valores entre 81,4 e 83,8. Ainda assim, o método FTIR-PLS mostrou-se bastante promissor como uma alternativa para a análise de gasolinas, podendo ser melhorado com a utilização de maior número de amostras de calibração e/ou com a utilização de um conjunto de amostras mais representativo, além da utilização de métodos de referência padrão.
Several gasoline properties (alcohol, benzene, aromatics, saturated and olefin contents, density, MON, RON and distillation temperatures) have been predicted simultaneously by spectroscopy in the region of the mid infrared (FTIR) and partial least squares regression (PLS). The methods used as reference have included ASTM and ABNT methods and the IROX equipment, based on spectroscopy in the region of the near infrared. Although the standard error of the prediction (RMSEP) has been the main considered parameter to select the best model of prediction for each property, the repeatability and the reproducibility have also been evaluated. In general, the properties determined by IROX as the reference method (all the constituents, MON and RON) have presented poor results, the worst one found being the olefins content (21,3 +- 2,4) and the best one MON (82,5 +- 0,5). In the case of the properties that had ASTM or ABNT methods as reference (alcohol content, density and distillation temperatures) the worst results were found for the alcohol content (23,9 +- 0,7) and the best one for the density (0,7556 +- 0,0025). However, even values of RMSEP found by PLS regression had been considered small, the correlation coefficients (R2) between the predicted values and reference values, for a set of samples independent of the calibration, have been shown to be below 0,70, for all the properties. This fact can be explained by the small variation in the values of some properties, as MON, that in all gasoline samples presented values between 81,4 and 83,8. FTIR-PLS method revealed promising as an alternative for gasoline analysis. This method could be improved with the use of a greater set of calibration samples and/or with the use of a more representative sample set, beyond the use of standard reference methods.
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Muthudoss, Prakash. "Application of FTIR imaging and spectroscopy to solid dosage formulations." Thesis, Sheffield Hallam University, 2011. http://shura.shu.ac.uk/20107/.
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The preparation of solid dispersions, in this study felodipine/polyvinyl pyrrolidone solid dispersion, is a multifaceted phenomenon. In order to understand the formation of solid dispersions two different mixed solvent system, three different temperatures and different drug loadings were selected and monitored in real time using Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy. 50 mul of the prepared solution was placed onto a pre-heated ATR crystal. The effect of PVP/API ratio, molecular interactions and effect of temperature (30°C, 40°C and 50°C) on the rate of film formation (solid dispersions) was evaluated. The changes in the peak positions, peak intensities and peak width as a function of time was monitored. The data were then analysed using peak height measurements, statistical and chemometric data analytical tools. It was shown that the nature of the solvent, the working temperature, presence of polymer and low drug loading was found to influence the rate of evaporation of solvent, molecular interactions and quality of the final product. Moreover, using thermogravimetric techniques it was complemented that the residual solvent within the systems was within the studied limits. The spatial arrangement or distribution of components within solid dispersion was found to influence the physical stability, phase behaviour, dissolution and bioavailability. Mid infrared spectroscopic imaging has been shown to be useful and has provided unique insights in to various fields. However, it has very limited applications in analysing the pharmaceutical materials. This work aims to evaluate various image processing tools in extracting process related information. Three model systems with varying chemical composition were selected. The chemical images from the regions of interest were collected using a Varian 620 FTIR Imaging instrument equipped with 64 x 64 MCT-Focal Plane Array (FPA) detector. Firstly we showed the impact of optical artefacts on the quality of the acquired image. The data was then pre-processed to remove baseline effects, pathlength variations and image processed to extract distribution maps. Agreement between the data generated using peak height measurements, compare correlation, principal component analysis and multivariate curve resolution was obtained only with the simple systems, the advantage with the latter being that the supervised and unsupervised chemometric approaches do not require any prior information about the sample and does not suffer from any physical or chemical interferences. The success of MCR-ALS over compare correlation and PCA methods is that it does not require any pure materials library and provides chemical information respectively. Moreover, implementation and data extraction is easy using MCR-ALS. It was then showed that once the optical artefacts are separated and chemically significant information is extracted, the benefits of infrared imaging was multitude. The optimised procedures were then applied to other samples to expand the applications of mid infrared imaging. There is no established paper to date describing the application of FTIR imaging to study the solvent induced phase separation in solid dispersions. One of the aims of this work is to study the impact of two different solvents on the phase behaviour of felodipine/polyvinyl pyrrolidone solid dispersions cast from different binary solvent systems. The temperature induced phase separation and degradation have been studied using differential scanning calorimetry, scanning electron microscopy, thermogravimetric etc, however we have shown the application of FTIR imaging in assessing the temperature induced degradation complemented and supported by in situ ATR-FTIR spectroscopy and thermogravimetric analysis.
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Yushchenko, Tetyana [Verfasser]. "PolyQ aggregation studied by ATR-FTIR difference spectroscopy / Tetyana Yushchenko." Konstanz : Bibliothek der Universität Konstanz, 2017. http://d-nb.info/1141576317/34.
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SuleÌ-Suso, Josep. "Autologous cell approaches to diagnosis and therapy in oncology." Thesis, Keele University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252570.
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Dong, Jun. "Development of Fourier transform infrared, FTIR, spectroscopy for determining oil quality." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0001/MQ29683.pdf.
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Ma, Kangming. "Peroxide value and trans analyses by Fourier transform infrared (FTIR) spectroscopy." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0032/NQ64609.pdf.
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Ma, Kangming 1965. "Peroxide value and trans analyses by Fourier transform infrared (FTIR) spectroscopy." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36643.
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New Fourier transform infrared (FTIR) approaches for the quantitative determination of peroxide value (PV) and isolated trans analyses were investigated and developed. The FTIR-PV methods investigated were all based on the stoichiometric reaction of hydroperoxides and triphenylphosphine (TPP) which converts TPP to triphenylphosphine oxide (TPPO). A reference transmission cell (100 mum) method was developed based on the use of a unique TPPO absorption at 542 cm-1. This method covered PV values from 0--15 PV and was shown to be superior in accuracy and reproducibility to the standard American Oil Chemists Society (AOCS) iodometric method. Subsequently, the utility of disposable polyethylene cards, normally used only for qualitative analyses, was investigated for quantitative PV determination. A quantitative IR card method was successfully developed and shown to serve as a very simple, rapid and alternative means of carrying out PV analyses. TPP-impregnated cards were able to reproduce the transmission cell PV results to +/-1.12 PV, while the unimpregnated card was slightly more accurate (+/-0.92 PV). A third FTIR-PV method was developed specifically for the at-line monitoring of high PV fatliquors and employed a germanium attenuated total reflectance sample handling accessory. This method hinged on the use of a TPPO absorption band at 1118 cm-1, normally off scale when pathlengths of >3 mum are used, but is suited to the analysis of oils having very high PVs (>250). The successful quantitative use of the disposable polyethylene IR card to PV led to its study for the quantitative FTIR determination of the isolated trans content of fats and oils and margarines. The polyethylene card was shown to unique and useful properties, tending to inhibit fat crystallization and its inability to retain moisture. These two properties allowed trans determination to be carried out on melted, high trans fats, without heating the polyethylene substrate and also to analyze margarines
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Dong, Jun 1971. "Development of Fourier transform infrared (FTIR) spectroscopy for determining oil quality." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27308.
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In this work, a rapid Fourier transform near infrared (FT-NIR) spectroscopic peroxide value (PV) method was developed and a prototype Continuous Oil Analysis and Treatment (COAT) system was assessed for monitoring and analytical purposes. High erucic acid rapeseed oil, a principle representative of triglyceride based oils suitable for biodegradable lubricating applications and mineral oil were used to test the methodology developed.The FT-NIR PV method is based on a well defined stoichiometric reaction of triphenylphospine (TPP) with hydroperoxides to form triphenylphospine oxide (TPPO). A partial least squares calibration model for the prediction of PV was developed using the NIR spectral region where TPP and TPPO co-absorb. The resulting calibration was highly linear over the analytical range of 100PV. Validation of the method carried out by comparing the PV of PLS prediction to the results of AOCS iodometric procedures indicated an excellent concurrence between the two methods. By programming the FT-NIR spectrometer, the analytical procedure simply consists of the addition of TPP stock solution to oil sample, mixing, taking its spectrum and predicting PV value. Through selected testing procedures, the prototype COAT system utilizing FTIR spectroscopy, advanced sample handling system designs, and computer programming was proved to be effective in monitoring the oil quality and behavior of antioxidants in real time.
Both approaches offer combined advantages of speed, accuracy, low labor cost, automation, and environmental friendliness mainly derived from FTIR spectroscopy, and can serve as convenient means for routine quality control applications in oils and fats industry. Potential application based on the joint usage of the two methods in the obtaining of true value of oil stability was also presented in this text. (Abstract shortened by UMI.)
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Jawurek, Michael [Verfasser]. "Protein-membrane interactions investigated with time-resolved FTIR spectroscopy / Michael Jawurek." Konstanz : Bibliothek der Universität Konstanz, 2017. http://d-nb.info/1151957127/34.
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SPRIGGS, LAURA S. "EXAMINATION OF THE AMMONIA - SULFUR DIOXIDE - WATER SYSTEM USING FTIR SPECTROSCOPY." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1022590722.
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Hallinan, Daniel T. Jr Elabd Yossef A. "Transport in polymer electrolyte membranes using time-resolved FTIR-ATR spectroscopy /." Philadelphia, Pa. : Drexel University, 2009. http://hdl.handle.net/1860/3055.
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Schönborn, Matthias [Verfasser]. "Time-resolved step-scan FTIR spectroscopy on photosystem II / Matthias Schönborn." Berlin : Freie Universität Berlin, 2018. http://d-nb.info/115023802X/34.
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Martí, Aluja Idoia. "Analysis of polymerisation / aggregation processes by nir chemical imaging and ftir spectroscopy." Doctoral thesis, Universitat Rovira i Virgili, 2013. http://hdl.handle.net/10803/125668.
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El principal objectiu d’aquesta tesi és desenvolupar mètodes analítics basats en la combinació entre l’espectroscòpia d’infraroig i tècniques quimiomètriques per analitzar in situ un procés de polimerització i l’agregació de la insulina. El procés de polimerització es va monitoritzar mitjançant la tècnica de near-infraredchemicalimaging (NIR-CI). L’anàlisi quimiomètric de les dades obtingudes ha permès evidenciar la presència d’un equilibri tautomèric d’un dels reactius. El segon procés estudiat ha estat l’agregació de la insulina, establint diverses metodologies basades en l’espectroscòpia d’infraroig (IR). Aquestes metodologies han permès, per una banda, avaluar l’efecte de fàrmacs antiretrovirals en el procés; i per altra banda, la influència de les tres variables bioquímiques més importants (temperatura, pH i força iònica) en el procés.The overall objective of this thesis is to develop analytical methods based on infrared spectroscopy and chemometric techniques to analyse two different processes that involve a state change from a liquid to a solid. The first studied process is a polymerisation process and it was followed by near-infrared chemical imaging (NIR-CI). The chemometric treatment of the images acquired allowed evidencing a tautomer’s equilibrium of one of the reagents. The second studied process was insulin aggregation. Aggregation process was monitored infrared spectroscopy (IR), and different methods were established which allowed on the one hand the assessment of the effect of antiretroviral drugs on the process; and on the other hand, the influence of biochemical variables on the process.
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Li, Liang. "In-line monitoring of styrene1,3 butadiene emulsion polymerization by ATR-FTIR spectroscopy." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28415.
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Synthetic rubber is a highly valuable commodity polymer. One important synthetic rubber product is styrene-butadiene rubber (SBR). It is principally made via the emulsion copolymerization of styrene and butadiene monomers and the product is referred to as emulsion polymerized SBR or E-SBR. It is one of the most widely used polymers in the world today. Typical E-SBR applications include pneumatic tires and tubes; heels and soles for footwear; and gaskets.
This study focused on demonstrating and validating the use of Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy to the in-line monitoring of E-SBR copolymerization. Based on this objective, a series of styrene/1, butadiene emulsion copolymerizations of different monomer feed ratios were carried out in a 12L stainless steel reactor using a typical industrial recipe. A special sample-taking valve was developed to account for the presence of the 1,3 butadiene (a gaseous monomer at atmospheric conditions). Monomer conversion was monitored off-line using gravimetry combined with proton nuclear magnetic resonance (1H-NMR) spectroscopy and in-line using ATR-FTIR spectroscopy.
The in-line ATR-FTIR monitoring was accomplished with a ReactIR(TM) 1000 probe. It was found that a multivariate statistical analysis (Partial Least Squares) was necessary to achieve good results. A comparison of the off-line and in-line results was made and it was demonstrated that no significant differences existed between the two methods. This confirmed the reliability of ATR-FTIR as a tool for monitoring monomer conversion and polymer composition for the E-SBR process.
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Dong, Jun 1971. "Quantitative condition monitoring of lubricating oils by Fourier transform infrared (FTIR) spectroscopy." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36915.
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Three new quantitative Fourier transform infrared (FTIR) spectroscopic methods were developed to measure key lubricant condition monitoring parameters; total acid number (TAN), total base number (TBN), and moisture (H2O). All methods employ a common sample-handling accessory and are based on the addition of specific reagents designed to react stoichiometrically with target species in oils, with quantification being carried out using differential FTIR spectroscopy. The combined use of a stoichiometric reaction and differential spectroscopy overcomes the need for a reference oil, which has traditionally hindered quantitative analysis of lubricants by FTIR spectroscopy. Potassium hydroxide, trifluoroacetic acid (TFA) and 2,2-dimethoxypropane (DMP) were the stoichiometric reagents used to develop the FTIR TAN, TBN and H2 O methods, respectively. Calibrations were developed using either peak height measurements or partial least squares (PLS) regression and the methods were validated using standard addition techniques, as the ASTM (American Society of Testing and Materials) standard methods were not sufficiently reproducible to make valid comparisons. Validation of the methods indicated that the TAN, TBN and H2O methods had accuracies of +/-0.095 mg KOH/g, +/-0.5 mg KOH/g and +/-32ppm respectively and corresponding reproducibilities of +/-0.05 mg KOH/g, +/-0.17 mg KOH/g and +/-22 ppm. The TAN, TBN and H2O methods were implemented on a Continuous Oil Analysis and Treatment (COATRTM) System, integrating instrumentation, software and sample handling so as to provide packaged, user and environmentally friendly analytical methods that are alternatives to conventional ASTM wet chemical methods.
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Campbell, Richard Antony. "External reflection FTIR spectroscopy of surfactants at the dynamic air-water interface." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418813.
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Lee-Montiel, Felipe, Kelly Reynolds, and Mark Riley. "Detection and quantification of poliovirus infection using FTIR spectroscopy and cell culture." BioMed Central, 2011. http://hdl.handle.net/10150/610169.
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BACKGROUND:In a globalized word, prevention of infectious diseases is a major challenge. Rapid detection of viable virus particles in water and other environmental samples is essential to public health risk assessment, homeland security and environmental protection. Current virus detection methods, especially assessing viral infectivity, are complex and time-consuming, making point-of-care detection a challenge. Faster, more sensitive, highly specific methods are needed to quantify potentially hazardous viral pathogens and to determine if suspected materials contain viable viral particles. Fourier transform infrared (FTIR) spectroscopy combined with cellular-based sensing, may offer a precise way to detect specific viruses. This approach utilizes infrared light to monitor changes in molecular components of cells by tracking changes in absorbance patterns produced following virus infection. In this work poliovirus (PV1) was used to evaluate the utility of FTIR spectroscopy with cell culture for rapid detection of infective virus particles.RESULTS:Buffalo green monkey kidney (BGMK) cells infected with different virus titers were studied at 1 - 12 hours post-infection (h.p.i.). A partial least squares (PLS) regression method was used to analyze and model cellular responses to different infection titers and times post-infection. The model performs best at 8 h.p.i., resulting in an estimated root mean square error of cross validation (RMSECV) of 17 plaque forming units (PFU)/ml when using low titers of infection of 10 and 100 PFU/ml. Higher titers, from 103 to 106 PFU/ml, could also be reliably detected.CONCLUSIONS:This approach to poliovirus detection and quantification using FTIR spectroscopy and cell culture could potentially be extended to compare biochemical cell responses to infection with different viruses. This virus detection method could feasibly be adapted to an automated scheme for use in areas such as water safety monitoring and medical diagnostics.
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Chatterton, Logan. "Spectral analysis of petroleum reservoir rock using fourier transform infrared (FTIR) spectroscopy." Thesis, Oklahoma State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10140532.
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Compositional analysis of reservoir rock is a vital aspect of oil exploration and production activities. In a broad sense, knowing the mineral composition of a reservoir can help with characterization and interpretation of depositional environments. On a smaller scale, identifying mineralogy helps calibrate well logs, identify formations, design drilling and completion programs, and screen for intervals with potential problem minerals, such as swelling clays. The petroleum industry utilizes two main methods to find compositional mineralogy, x-ray diffraction (XRD) and thin section analysis. Both methods are time consuming, expensive, and destructive. An alternative method for compositional analysis that includes quantitative mineralogy is a valuable prospect, especially if it had the potential to characterize the total organic content (TOC).
The remote sensing community has been using infrared spectroscopy to analyze mineralogy for years. Within the last ten years, the advancement of infrared spectrometers and processing programs have allowed infrared spectra to be taken and analyzed faster and easier than before. The objective of this study is to apply techniques used in remote sensing for quantitatively finding mineralogy to the petroleum industry. While developing a new methodology to compositionally analyze reservoir rock, a database of infrared spectra of relevant minerals has been compiled. This database was used to unmix spectra using a constrained linear least-squares algorithm that is used in the remote sensing community. A core has been scanned using a hand-held infrared spectrometer. Results of the best method show RMS error from mineral abundance to be under five percent.
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Goldsztein, Andrea. "Development of a new type of biosensors based on ATR-FTIR spectroscopy." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209653.
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Les biosenseurs sont des dispositifs analytiques utilisés pour la détection de reconnaissance moléculaire. Ils consistent en un élément biologique immobilisé en contact intime avec un transducteur approprié qui convertit un signal biochimique en un signal électrique quantifiable. Leur principe est basé sur la reconnaissance d'une ou plusieurs molécules d'intérêt en solution (le ligand), par un composant biologique (le récepteur) étroitement lié au substrat transducteur. Le senseur réagit aux interactions récepteur-ligand et produit un signal mesurable, généralement proportionnel à la concentration du ligand fixé. Les biosenseurs sont déjà utilisés dans beaucoup de domaines différents, notamment dans le domaine médical (diagnostique et thérapeutique), le contrôle de l’environnement, et l’analyse et le monitoring de processus biotechnologiques. La recherche concerne la mise au point d’un nouveau type de biosenseurs polyvalents à haute performance. Ces senseurs utilisent un élément de transduction optique dont la surface a été fonctionnalisée en vue de permettre la détection sélective d'interactions récepteur-ligand ainsi que le dosage des molécules fixées aux récepteurs. La technique utilisée pour la détection et le dosage est celle de la Spectroscopie ATR-FTIR (Spectroscopie Infra Rouge à Transformée de Fourrier en Réflexion Total Atténuée). Le système permet la détection directe, en temps réel, et sans marquage des molécules ciblées. La spectroscopie ATR-FTIR fournit une analyse des molécules sur base de leur empreinte spectrale infra rouge (IR) caractéristique, ce qui offre une mine d'informations pour identifier les ligands. Ce nouveau système de biosenseur, appelé BIA-ATR (Biospecific Interaction Analysis – Attenuated Total Reflection) est original et offre des avantages majeurs par rapport à la plus part des biosenseurs commercialement disponibles. Il fournit à l’utilisateur le spectre IR entier du ligand étudié, permettant non seulement le dosage quantitatif de ce dernier, mais aussi d’identifier sa nature intrinsèque. Un autre avantage est sa grande sensibilité ;le senseur BIA-ATR peut détecter la fixation de petites molécules et dans certains cas, aussi les réactions chimiques associées.
Le potentiel de cette nouvelle technologie de senseur est évalué dans ce travail par son application à plusieurs systèmes d’intérêt biologique et médical :la détection de protéines en milieux complexes, appliquée à la détection du Facteur VIII de coagulation du sang impliqué dans l’hémophilie de type A ;la fixation d’une petite molécule, le phosphate (phosphorylation), sur l’ATPase gastrique, un récepteur protéique de grande taille responsable de la sécrétion d’acide dans l’estomac et la détection et dosage d’un antibiotique, la vancomycine, utilisé en soins intensifs hospitaliers dans les cas d’infections bactériennes sévères à Staphylocoques dorés.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Horikawa, Yoshiki. "Characterization of native cellulose by FTIR spectroscopy combined with deuteration/rehydrogenation technique." Kyoto University, 2008. http://hdl.handle.net/2433/136604.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第13877号
農博第1692号
新制||農||954(附属図書館)
学位論文||H20||N4344(農学部図書室)
UT51-2008-C793
京都大学大学院農学研究科森林科学専攻
(主査)教授 杉山 淳司, 教授 西尾 嘉之, 教授 中野 隆人
学位規則第4条第1項該当
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Saint, Clair Erica C. "FTIR difference and resonance raman spectroscopy of rhodopsins with applications to optogenetics." Thesis, Boston University, 2013. https://hdl.handle.net/2144/11038.
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Thesis (Ph. D.)--Boston UniversityThe major aim of this thesis is to investigate the molecular basis for the function of several types of rhodopsins with special emphasis on their application to the new field of optogenetics. Rhodopsins are transmembrane biophotonic proteins with 7 a-helices and a retinal chromophore. Studies included Archaerhodopsin 3 (AR3), a light driven proton pump similar to the extensively studied bacteriorhodopsin (BR); channelrhodopsins 1 and 2, light-activated ion channels; sensory rhodopsin II (SRII), a light-sensing protein that modulates phototaxis used in archaebacteria; and squid rhodopsins (sRho), the major photopigment in squid vision and a model for human melanopsin, which controls circadian rythms. The primary techniques used in these studies were FTIR difference spectroscopy and resonance Raman spectroscopy. These techniques, in combination with site directed mutagenesis and other biochemical methodologies produced new knowledge regarding the structural changes of the retinal chromophore, the location and function of internal water molecules as well as specific amino acids and peptide backbone. Specialized techniques were developed that allowed rhodopsins to be studied in intact membrane environments and in some cases in vivo measurements were made on rhodopsin heterologously expressed in E. coli thus allowing the effects of interacting proteins and membrane potential to be investigated. Evidence was found that the local environment of one or more internal water molecules in SRII is altered by interaction with its cognate transducer, Htrii, and is also affected by the local lipid environment. In the case of AR3, many of the broad IR continuum absorption changes below 3000 cm-1, assigned to networks of water molecules involved in proton transport through cytoplasmic and extracellular portions in BR, were found to be very similar to BR. Bands assigned to water molecules near the Schiff base postulated to be involved in proton transport were, however, shifted or absent. Structural changes of internal water molecules and possible bands associated with the interaction with ,8-arrestins were also detected in photoactivated squid rhodopsin when transformed to the acid Meta intermediate. Near-IR confocal resonance Raman measurements were performed both on AR3 reconstituted into E. coli polar lipids and in vivo in E. coli expressing AR3 in the absence and presence of a negative transmembrane potential. On the basis of these measurements, a model is proposed which provides a possible explanation for the observed fluorescence dependence of AR3 and other microbial rhodopsins on transmembrane potential.
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Radu, Ionela. "FTIR spectroscopy of the photophobic sensory rhodopsin II-transducer complex from Natronabacterium pharaonis." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=97889426X.
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Toh, Shin Yi. "Conformational and UV photochemistry studies of amino acids in matrix-isolation FTIR spectroscopy." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58582.
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McKendrick, Alexander David. "Thermal emission decay FTIR spectroscopy and phantom studies for in-vivo skin research." Thesis, London South Bank University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336308.
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Chen, Ziyu. "The crystallization of poly(ethylene terephthalate) studied by thermal analysis and FTIR spectroscopy." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4251/.
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This thesis concerns the thermal behaviour and properties, isothermal crystallization kinetics and seeded crystallization study of Poly (ethylene terephthalate) (PET) using thermal analysis Fourier transform infrared (TA-FTIR), two-dimensional infrared correlation spectroscopy (2D-FTIR) and differential scanning calorimetry (DSC). TA-FTIR has been used to characterize phase transitions by a change in the absorbance or peak position with temperature in thermal cycling. It assigns the phase transition temperature to an individual chain segment and observes two different types of thermal behaviours of the functional groups. FTIR finds out that the carbonyl stretching band has an amorphous band and a crystalline band following by analysis of 2D-FTIR. The isothermal crystallization kinetics of PET was measured from 230 to 240\(^o\)C by FTIR focusing on carbonyl ester group. The deconvolution of these two overlapping absorption bands analyzes the kinetics of both primary and secondary crystallization by Avrami equations. Melting behaviour study on DSC observes crystallinity, melting temperature and calculated lamellae thickness of PET increase with the extending time period of isothermal crystallization in secondary process. Seeded crystallization crystallizes polymers at higher temperatures to produce greater lamellae thicknesses and higher melting temperature and to discuss the effect of this morphology on their mechanical and physical properties.
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Smith, Thomas. "Evaluation and application of FTIR spectroscopy for field study of biomass burning emissions." Thesis, King's College London (University of London), 2013. https://kclpure.kcl.ac.uk/portal/en/theses/evaluation-and-application-of-ftir-spectroscopy-for-field-study-of-biomass-burning-emissions(0aaebade-48f6-4707-9978-23f5a2d2d37e).html.
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An average of 3.5-4.5 million square km of vegetation burns in global wildfires each year. The gases and particulates released have substantial chemical and radiative impacts, the magnitude of which depends on the specific makeup and magnitude of the emissions. This research focuses on the development, evaluation and application of field-deployed methods based around Fourier transform infrared (FTIR) spectroscopy for the assessment of the emissions from biomass burning events. In particular, full assessment of the atmospheric effects of biomass burning generally requires spatio-temporally resolved data on the makeup and magnitude of the smoke emissions. This is usually obtained via multiplication of the amount of fuel consumed [M] by an emission factor [EFX], representing the amount of chemical species [x] released per kilogram of dry fuel burned. Emissions factors for many species typically show wide ecosystem variations, and also vary with meteorology and fire type, increasing the uncertainty in this important variable. When compared to established point-sampling methods, OP-FTIR spectroscopy can measure many different gases simultaneously, in situ and near-continuously, and can provide path-integrated amounts. Few studies, however, have investigated the accuracy of the retrievals of the main biomass burning gases (CC>2, CO and CH4), particularly across the broad range of concentrations found in ambient air to biomass burning plumes. Laboratory gas cell experiments were first used to evaluate the accuracy of the FTIR spectrometer and spectral analysis methodology deployed to retrieving concentrations of these gases at open biomass burning sites. The findings suggest that with optimisation of the retrieval parameters, column amounts accurate to within 5% can be confidently derived. During 2009-2011, the FTIR equipment was deployed to a number of experimental fires for the purpose of improving our understanding of emission factors. Three case studies are presented in this thesis: 1. Determining the seasonality of biomass burning emissions in Australian savanna lands - Seasonal (early- and late-dry season) emission factors were measured and compared, revealing no evidence of seasonality of emissions, in contrast to some previous works. Instead, Modified Combustion Efficiency explains most of the variation (e.g. 95% for CH4) in emission factors 2. Building an emissions inventory for UK fuel types - Emission factors for heather (Calluna vulgaris) were measured here for the first time, enabling the first measurement-based estimates of total UK biomass burning emissions for the main carbonaceous gases and selected volatile organic compounds. Typical flaming combustion emission factors for CC>2, CO, CFLt and NH3 are around 1711, 66.2, 2.8 and 0.53 g kg"1 dry fuel combusted, respectively. 3. Determining emission ratios using solar occultation FTIR spectroscopy of lofted plumes from large wildfires in the Northern Territory, Australia, and comparison of total column trace gas amounts with simultaneous and collocated measurements of Aerosol Optical Depth (AOD). The emission ratio of NH3 to CO determined from solar measurements is shown to agree with that measured on the ground using OP-FTIR. A relationship is established between total column amounts of CO and AOD, confirming that satellite-derived measures of AOD could be used as a proxy for trace gas amounts. Further work includes an exploration of the use of field-deployed FTIR in the study of aerosols in biomass burning plumes.
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Carabante, Ivan. "Study of arsenate adsorption on iron oxide by in situ ATR-FTIR spectroscopy." Licentiate thesis, Luleå tekniska universitet, Industriell miljö- och processteknik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26159.
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Stabilization of arsenic contaminated soils by iron oxides has been proposed as a remediation technique to prevent leaching of arsenate into the environment. However, fundamental studies are needed to establish under which conditions the complexes formed are stable. A new method based on ATR-FTIR spectroscopy was adapted to study the adsorption of arsenate species on iron oxides. The measurements required the use of D2O as solvent. The amount of arsenate complexes adsorbed on the iron oxide increased with decreasing pD in the range studied, viz. pD 4-12. Arsenate complexes adsorbed at pD 4 desorbed from the film to some extent as the pD was increased to 8.5 or 12. The stability of arsenate complexes adsorbed on the iron oxide evidently changed with the change in pD, most likely due to the electrostatic repulsion between the negatively charged oxoanion and the more negatively charged iron oxide as the pD increased. From competitive adsorption experiments it was found that arsenate species were more strongly bonded to the iron oxide than phosphate species. Furthermore, it was found that two different phosphate complexes formed on the iron surface at pD 4, one deuterated and the other one de-deuterated. The complexes showed very different stability. The deuterated phosphate complex was desorbed easily from the iron oxide film as arsenate was added to the system whereas the de-deuterated phosphate complex only desorbed slightly from the film upon adding arsenate.This work has increased the fundamental knowledge of the iron oxide/arsenate/phosphate system, which will be of importance for the development of more effective soil remediation techniques.Godkänd; 2009; 20090905 (ivacar); LICENTIATSEMINARIUM Ämnesområde: Kemisk teknologi/Chemical Technology Examinator: Professor Jonas Hedlund, Luleå tekniska universitet Tid: Fredag den 2 oktober 2009 kl 10.00 Plats: C 305, Luleå tekniska universitet
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Vegunta, Vijaya Lakshmi. "A study on the thermal stability of sodium dithionite using ATR-FTIR spectroscopy." Thesis, KTH, Fiber- och polymerteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-197370.
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Sodium dithionite (Na2S2O4) is a powerful reducing agent. It has therefore been suggested to be used as an additive in kraft pulping to improve the yield. However, sodium dithionite easily decomposes and it is thus important to determine the effect of different conditions. The aim of this thesis has been to investigate the thermal stability of sodium dithionite under anaerobic conditions using ATR-FTIR spectroscopy under different conditions, such as heating temperature, concentration of the solution, heating time and pH. The stability of sodium dithionite was found to decrease with increasing heating temperature, concentration of sodium dithionite, heating time and pH. Sodium dithionite was found to be relatively stable at moderate alkaline pH:s 11.5 and 12.5, while a rapid decrease in stability with time was noted at higher heating temperatures and concentrations of sodium dithionite. Based on this study on the thermal stability of sodium dithionite, the following conditions are suggested as the most promising, when adding sodium dithionite to the kraft cooking as an additive; pH 12.5, with 0.4 M concentration of the solution, at a heating temperature of 100 °C.
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Carabante, Martinez Ivan. "Study of arsenate adsorption on iron oxide by in situ ATR-FTIR spectroscopy /." Luleå : Luleå University of Technology, 2009. http://pure.ltu.se/ws/fbspretrieve/3061105.
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Parikh, Sanjai Jagadeep. "A Spectroscopic Study of Bacterial Polymers Mediating Cell Adhesion and Mineral Transformations." Diss., Tucson, Ariz. : University of Arizona, 2006. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1456%5F1%5Fm.pdf&type=application/pdf.
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Carrott, Michael J. "Supercritical fluid chromatography and spectroscopic detection." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388419.
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Feeney, Kevin Anthony. "Expression and characterisation of perfect repeat peptides based on a wheat glutenin protein." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340155.
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Batistuti, Marina Ribeiro. "Classificação de fungos através da espectroscopia no infravermelho por transformada de Fourier." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/59/59135/tde-31012013-094052/.
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A identificação de isolados dentro de algumas espécies de fungos filamentosos é de interesse médico, agrícola e industrial. Dentro do gênero Metarhizium, por exemplo, a identificação de espécies vêm sendo constantemente modificada devido a análise genética. Nesse contexto, o desenvolvimento de novas estratégias para a identificação rápida e confiável de microrganismos de maneira geral, e de fungos especificamente, é desejável. A espectroscopia no infravermelho por transformada de Fourier (FTIR) tornou-se amplamente difundida na medicina e biologia por fornecer rapidamente informações capazes de caracterizar bioquimicamente uma amostra. Assim, o objetivo desta pesquisa foi utilizar a espectroscopia de FTIR para a caracterização e classificação de linhagens e de espécies dos gêneros Aspergillus e Metarhizium, além da comparação entre diferentes metodologias para classificação. Foram selecionadas duas espécies do gênero Aspergillus: Aspergillus nidulans (ATCC 10074); Aspergillus flavus (ATCC 1410) com conídios verde e branco, obtidas da ATCC \"American Type Culture Collection\"(Manassas, VA), e seis espécies do gênero Metarhizium: Metarhizium acridum (ARSEF 324); Metarhizium acridum (ARSEF 3391); Metarhizium acridum (ARSEF 7486); Metarhizium anisopliae (ARSEF 5749); Metarhizium brunmeum (ARSEF 1095) e Metarhizium brunmeum (ARSEF 5626), obtidas da \"USDA-ARSEF collection of Entomopathogenic Fungal Cultures\"(U.S. Plant, Soil and Nutrition Laboratory, Ithaca, NY). O cultivo de todas as espécies foi feito em laboratório. As espécies A. nidulans ATCC 10074 e M. acridum ARSEF324 foram usadas para avaliar a influência da luz e do pH do meio de cultura sobre o crescimento dos fungos. Os valores de pH do meio estudados variaram ente 5 e 8. Para obter os espectros de absorção, os conídios foram delicadamente retirados e depositados sobre o cristal de ATR do espectrômetro do FTIR. Os espectros foram normalizados vetorialmente e subdivididos em quatro intervalos: 910-1178 cm-1 , 1178-1490 cm-1 , 1490-1790 cm-1 e 2810-2990 cm-1 . Parâmetros espectroscópicos como o deslocamento do pico de absorção e as razões entre áreas sob as bandas foram calculadas para todos os espectros coletados. O teste estatístico t-Student foi aplicado a estes parâmetros para diferenciar as amostras. Ambas as análises foram realizadas pelo programa Origin 8.5. A análise de componentes principais e agrupamento foram realizada usando o programa Minitab 16. As técnicas utilizadas para análise foram capazes de diferenciar as amostras de Aspergillus crescidas na presença e na ausência de luz, mas o mesmo não foi possível para o Metarhizium. Dentre os valores de pH do meio de cultura foi possível apenas a diferenciação do pH 8. O A. flavus com conídios brancos e verdes foram diferenciados entre si assim como entre eles e os A. nidulans. Entre as espécies foi possível obter a classificação de acordo com a taxonomia através da região espectral 1178-1490 cm-1. As quatro metodologias foram consideradas adequadas para análise dos espectros de absorção, entretanto o deslocamento de pico e a razão entre as áreas são viáveis apenas para um número pequeno de amostras enquanto o PCA e o cluster são viáveis para um número grande de amostras.The identification of isolates within some species of filamentous fungi has medical, agricultural and industrial interest. Within the genus Metarhizium, for example, species identification is being constantly changed due to genetic analysis. In this context, the development of new strategies for the rapid and reliable identification of microorganisms in general, and specifically of fungi is desirable. Fourier Transform Infrared Spectroscopy (FTIR) has become widespread in medicine and biology by providing information quickly able to biochemically characterize a sample. The aim of this research was to use FTIR spectroscopy for characterization and classification of strains and species of the genera Aspergillus and Metarhizium and compare different methods for classification. We selected two strains of the genus Aspergillus: Aspergillus nidulans (ATCC 10074), Aspergillus flavus (ATCC 1410) with green and white conidia, obtained from ATCC \"American Type Culture Collection\"(Manassas, VA), and six strains of Metarhizium: Metarhizium acridum (ARSEF 324); Metarhizium acridum (ARSEF 3391); Metarhizium acridum (ARSEF 7486), Metarhizium anisopliae (ARSEF 5749); Metarhizium brunmeum (ARSEF 1095) and Metarhizium brunmeum (ARSEF 5626), obtained the \"USDA-ARSEF collection of Entomopathogenic Fungal Cultures \"(U.S. Plant, Soil and Nutrition Laboratory, Ithaca, NY). The cultivation of all species were made in the laboratory. The species A. nidulans (ATCC 10074) and M. acridum (ARSEF 324) were used to evaluate the influence of light and pH of the culture medium on the growth of fungi. The pH values of the medium studied ranged between 5 and 8. To obtain the absorption spectra, the conidia were gently removed and deposited on the ATR crystal of FTIR spectrometer. The absorption spectra were vector normalized and divided in four ranges: 910-1178 cm-1, 1178-1490cm-1, 1490-1790cm-1 and 2810-2990cm-1. Spectroscopic parameters as the displacement of the absorption peak and the ratios of the areas under the bands were calculated for all spectra collected. The statistical test t-Student was applied on these parameters to differentiate the samples. Both analyzes were performed by the program Origin 8.5. The principal component analysis and cluster analysis were performed using Minitab 16. The techniques used for analysis were able to differentiate samples of Aspergillus grown in the presence and absence of light, but it was not possible to Metarhizium. Among the pH of the culture medium was only possible to identify the pH 8. The A. flavus with white and green conidia were differentiated among themselves and between them and the A. nidulans. Among the strains of the same specie it was possible to obtain the correct classification according to the taxonomy through spectral region 1178-1490 cm-1. The four methods were considered appropriate for the analysis of absorption spectra, however displacement of the absorption peak and the ratios of the areas are feasible for a small number of samples and the multivariate analysis are feasible for a large number of samples.
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Benetti, Carolina. "Estudo in-vitro dos efeitos do laser de Er,Cr:YSGG em tecido ósseo por espectroscopia ATR-FTIR." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-02082011-092521/.
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O laser tem se mostrado eficaz no auxílio ao profissional de saúde, sendo extensivamente utilizado em procedimentos médicos e odontológicos nas ultimas décadas. Em particular, os lasers de alta intensidade emissores no infravermelho possuem grande potencial para corte de tecidos biológicos mineralizados, visto que são bastante absorvidos pela hidroxiapatita e água, principais componentes desses tecidos. Em comparação aos instrumentos mecânicos, o laser apresenta uma série de vantagens no corte de tecidos, com possibilidade de menor dano ao tecido remanescente e melhor hemostasia. Entretanto, para uma aplicação eficiente e segura é necessário conhecer os efeitos que a irradiação laser causa ao tecido. A técnica de espectroscopia no Infravermelho por Transformada de Fourier (FTIR) é bastante utilizada no estudo de materiais orgânicos, pois além de permitir a identificação de componentes, possibilita uma análise semiquantitativa. Este trabalho tem como objetivos estabelecer a técnica de ATR-FTIR para caracterização do tecido ósseo natural e irradiado, e verificar as eventuais mudanças químicas e estruturais causadas pela irradiação laser. Primeiramente, foram determinadas as melhores condições instrumentais para a obtenção dos espectros de amostras de osso. Posteriormente foram analisadas as amostras de osso natural e irradiado com o laser de Er,Cr:YSGG (2,78 μm) com diferentes densidades de energia. Verificou-se que a técnica foi eficaz na caracterização do tecido ósseo, sendo possível observar as alterações químicas promovidas pelo aumento de temperatura ocasionado pela irradiação laser. Foi observada a perda gradativa de material orgânico em função do aumento da densidade de energia utilizada. Os resultados obidos são os primeiros passos para a verificação da eficácia do laser de Er,Cr:YSGG quando empregado como uma ferramenta de corte, essencial para sua consolidação na prática clínica.Laser proves to be, more and more, an effective tool for helping health professionals, being intensively used in ophthalmological and odontological procedures. In particular, high-density, infrared emitting lasers have great potential in cutting mineralized biological hard tissues, given their high absorption by hydroxyapatite and water, these tissues main components. In comparison to mechanical instruments, laser presents a series of advantages, namely, smaller damage to the remaining tissue and promotion of homeostatic effect, apart from making it possible to execute procedures in areas with difficult access. However, for an efficient and safe use of this technique, it is necessary to know the effects of the laser irradiation on the tissue. The Fourier transform infrared (FTIR) technique is heavily used in the study of organic materials, because apart from making it possible to identify the materials components, it also allows to prepare a semi quantitative analysis. This work aims to establish the ATR-FTIR technique in the characterization of natural and irradiated osseous tissue, and to verify the possible chemical and structural changes caused by irradiation. Firstly, the best conditions for the obtainment of bone sample spectra were determined. Then, bone samples, irradiated with the Er,Cr:YSGG (2,78 μm) infrared emitting laser (adjusted with different energy densities) were analyzed alongside with natural bone samples. It has been verified that the technique is effective in the bone tissue characterization, and that it is possible to observe the chemical changes caused by the temperature rise due to laser irradiation. It has been observed a gradual organic material loss as the energy density goes up. These results are the first steps in testing the Er,Cr:YSGG laser efficacy as a cutting tool, a pivotal aspect of its consolidation in clinical procedures.
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Maciejewski, Adam John Henry. "Remote measurements of volcanic gases : applications of open-path Fourier transform infra-red spectroscopy (OP-FTIR) and Correlation spectroscopy (COSPEC)." Thesis, Open University, 1998. http://oro.open.ac.uk/57874/.
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The composition of volcanic gas plumes depends largely on the chemistry of the degassing magma, the depth of volatile exsolution, and the level of volcanic activity. The ratios between the most common volcanic gases: C02, H2O, SO2, HCl and HF, as measured at the surface, can be used to provide information on the evolution of the magma body. My research on volcanic gases has centred on the use of open-path Fourier transform IR spectroscopy (Op_FTTR) and correlation spectroscopy (COSPEC). I have also used data collected using other direct and remote-sensing techniques. Remote-sensing techniques rely on the characteristic IR or UV absorbances of natural and/or artificial radiation by different gases. The longer range of these techniques enables the analysis of gases in inaccessible plumes; thus reducing the need for operators to enter hazardous areas. As the instruments do not interact with the analysed gases there is no contamination, condensation or secondary reactions. However, the instruments tend to be heavy, expensive, and complex. Environmental factors can complicate analyses; clouds can dissolve and remove analyte rapidly, and variations in wind speed can result in gas fluxes having high errors. It is also much more difficult to analyse specific gas sources remotely as mixing of gases from different sources can occur. Direct-sampling techniques rely on gases being trapped, dissolved or adsorbed before being analysed by traditional methods, e. g. wet-chemistry, colourimetry, and gas chromatography. The capture of gases is best achieved as close to the source as possible, thus increasing the risk to the operator, and may only be possible during periods of low activity. The physical interaction of gases with instrument and collection vessels can lead to contamination and initiation of secondary reactions. Direct-sampling techniques are labour intensive and thus are capable of only generating a relatively small amount of data compared to the more automated remote-sensing techniques. The suitability of an individual technique therefore depends greatly on: the type of gas to be measured; the location of vent or fumamle; the level of volcanic activity; and the environment in which data are collected. I used OP-FrIR on La Fossa di Vulcano to measure the S02: HCI mass ratios of gases emitted from the rim and central crater fumaroles, -4.3 - 6.1 and 0.9 - 2.6 respectively. I attributed the higher crater rim gas ratios to the interaction of the gases with shallow hydrothermal reservoirs, causing scrubbing of the more soluble HCl- At Mt. Etna, my OP-FTIR analysis of gases emitted from the central craters showed that, in 1994, S02: HC1 mass ratios were -4.9 - 5.8. These values lie between those reported for eruptive degassing, >10, and background degassing, < I, and probably relate to refilling of the magma system prior to the 1997 eruption. A comparative study of lava effusion rates and COSPEC-derived SO2 fluxes for the 1991 - 1993 Etna eruption showed that variations were generally synchronous; small scale differences relating to the drainage of degassed magma from beneath the summit craters into the eruptive fissure. I also conducted OP-FT'IR and COSPEC analyses on Montserrat in June 1996 to show the gas plume to be relatively S02 poor, with S02: HC1 mass ratios of < 0.5. The OP-FTIR technique enabled the first remote measurements of SiF4 in volcanic plumes to be made. I have also used HF-SiF4 ratios to estimate gas equilibrium temperatures at La Fossa and Mt. Etna to be --200°C and -250 - 290°C respectively. I have also investigated the structural evolution of the Masaya Volcanic Complex. The visible complex has formed over -1000 years; with average rates of effusion of -0.2 x 106 m3/y, much lower than those required to provide the estimated volume of caldera infill, -2 x 106 m3/y. Historic activity has centred on the twin massifs of Volcän Masaya and Volcän Santiago and is dominated by pit-crater collapses. I propose that the degassing episodes, which occur with no increase in eruptive activity, are related to the convective overturn of magma beneath the craters.
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Aisenbrey, Christopher. "Investigation of the topology of membrane polypeptides by solid state NMR spectroscopy and attenuated total reflection infrared spectroscopy (ATR-FTIR)." Université Louis Pasteur (Strasbourg) (1971-2008), 2003. http://www.theses.fr/2003STR13188.
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Cette thèse est divisée en trois parties qui suivent des approches différentes. Dans la première partie, l'hydrophobicité d'acides amines, propriété bien connue, est déterminée. Un modèle thermodynamique détaillé de la topologie de polypeptides dérivés du LAH4 en fonction du pH a été développé. Ces modifications dans la topologie ont été mises en évidence par la technique de spectroscopie infrarouge de réflexion totale atténuée. (abrégée en anglais ATR-FTIR). Grâce à ces résultats et à un modèle théoretique, nous avons pu déterminer l'enthalpie nécessaire à l'insertion d'acides aminés de la phase aqueuse vers l'intérieur d'une bicouche lipidique. La seconde partie donne une vue d'ensemble (avantages et limites) de l'utilisation de RMN du deutérium sur la 2H3C-alanine. Il est en effet prouvé que cette méthode peut fournir des informations sur la structure et la dynamique des polypeptides membranaires. Bien que la RMN du deutérium ait déjà été utilisée auparavant sur des peptides marqués à l'aide de 2H3C-alanine, l'étude systematique de tels peptides par cette technique éclaire de nouveaux aspects du sujet. Dans la troisième partie, la RMN à l'état solide est appliquée à différents polypeptides et protéines d'origine naturelle. Ainsi, pour la bacteriorhodopsine et la gramicidine A, certains détails de la structure déjà connue du protéine / polypeptide ont été néanmoins élucidés. La structure du ß-peptide amyloide dans sa forme membranaire est quant à elle largement inconnue : nous avons essayé de savoir si la RMN du solide pouvait fournir de plus amples informations. Enfin, pour les protéines colicine E1 et BCL-XL , nous avons testé la validité de modèles disponibles dans la littérature. Dans le cas du domaine formant le canal de la colicine E1, une protéine marquée uniquement à une seule position a été utilisée : les spectres 15N RMN à l'état solide sont parmi les premier mesurés pour une protéine exprimée par bactérie et marquée sur une seule positionThe thesis consists of three different sections, which follow slightly different approaches. In the first part the hydrophobicity a very basic property, of amino acids is determined. For the series of LAH4-like polypeptides a detailed thermodynamic model for the pH dependent topology of the peptides was developed. The topological changes were measured by attenuated total reflection infrared spectroscopy (ATR-FTIR). The results of the measurements and the theoretical model were used to determine the enthalpy for the insertion of some amino acid from water phase into the lipid bilayer interior. The second part gives a detailed overview of the advantages and problems of the application of deuterium NMR using 2H3C-Alanine. It is shown that the method can give valuable information of structure and dynamics of membrane polypeptides. Even thought solid-state NMR on 2H3C-Alanine labelled peptides was used before the systematic investigation of the properties of deuterium NMR on 2H3C-Alanine labelled peptides gives new and important aspects into the topic. In the third part the solid-state NMR method is applied to different natural polypeptides and proteins. For bacteriorhodopsin and gramicidine A solid-state NMR was used to investigate some details of the known structure of the protein/polypeptide. The structure of the membrane associated form of the amyloid b-peptide is widely unknown. It was tested, if solid-state NMR can provide further information of the membrane associated form of the amyloid b-peptide. For the proteins colicin E1 and BCL-XL detailed models are published and the solid-state NMR experiments are used to test these models. For the measurement of the channel-forming domain of colicin E1 a single-side labelled protein was used. The measured spectra belong to the first 15N solid-state NMR spectra of a single-side labelled protein (expressed in bacteria)
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Protsailo, Lesia V. "Characterization of the electrode/SAM/electrolyte interface and intermolecular interactions in solutions using electrochemical impedance spectroscopy and ATR-FTIR spectroscopy /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Gaigneaux, Anthoula. "Determination of diagnostic and prognostic markers in varied tumoral pathologies by ATR-FTIR spectroscopy." Doctoral thesis, Universite Libre de Bruxelles, 2004. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211150.
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Golebiowski, Dariusz. "High resolution FTIR spectroscopy using a femto-OPO laser source and cavity enhanced absorption." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/221150.
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Dans cette thèse, nous améliorons et utilisons le montage expérimental développé au laboratoire nommé femto/OPO-FT-CEAS. Ce montage combine une source laser femto/OPO, une cavité optique haute finesse et un interféromètre à transformée de Fourier. Il permet d'enregistrer des spectres sur un intervalle de 150 cm-1, avec un coefficient d'absorption minimal de 3x10-9 cm-1, à une résolution de 2x10-2 cm-1 et un temps d’acquisition de 2 heures. Un chemin d'absorption de 20 km a été obtenu dans une cellule de 145 cm. Différents miroirs à hauts indices de réflexion permettent d'accéder à deux gamme spectrales dans le domaine de l'infrarouge proche :6200-6700 cm-1 et 7700-8300 cm-1.Le montage femto/OPO-FT-CEAS a été utilisé afin d'enregistrer des spectres à température ambiante. La molécule OCS a été étudiée dans les gammes spectrales de 6200 à 6700 cm-1 et 7700 à 8300 cm-1. Les nouvelles données rovibrationnelles ont été intégrées au modèle global développé par le Prof. Fayt de l'université catholique de Louvain. Un échantillon de CO2 enrichi en oxygène 17 a également été étudié dans la gamme spectrale de 7700 à 8300 cm-1. Les données ont été traitées avec l'aide du Dr. Lyulin l'institut d'optique atmosphérique de Tomsk, Russie.Le montage femto/OPO-FT-CEAS a également été modifié pour enregistrer des spectres de molécules refroidies au sein d'un jet supersonique. Les molécules de N2O, C2H4 et H12C13CH en abondance isotopique naturelle ont été étudiées. Le montage permet de refroidir les molécules étudiées jusqu'à 10 K et un coefficient de 5x10-8 cm-1 a été obtenu. Ce montage a également permis d'enregistrer des spectres CEAS et CRDS de NH3 à des températures de 17 et 14 K respectivement. L'analyse des spectres aété réalisée avec l'aide des Profs. Fusina et Di Lonardo de l'Université de Bologne, Italie.Une cellule de 145 cm pouvant être refroidie à l'aide de réfrigérants liquides a également été développée en vue de remplacer une cellule à température ambiante de 77 cm utilisée dans le montage femto/OPO-FT-CEAS.Enfin, les montages FANTASIO+ et femto/OPO-FT-CEAS ont été utilisés afin afin d'enregistrer des spectres de HCOOH à température ambiante et à 10 K. Les données ont été traitées avec l'aide du Dr. Perrin de l'Université Paris-Créteil, France.Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Parkes, Stephen. "The isotopic signature of nitrous oxide emitted from agricultural soils measured by FTIR spectroscopy." School of Chemistry, Faculty of Science, 2008. http://ro.uow.edu.au/theses/129.
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Agriculture contributes 16% to Australia’s greenhouse gas emissions, of which 23% are the result of nitrous oxide (N2O) emissions. Global N2O emissions from agricultural activities have increased substantially since the beginning of the industrial revolution. This has been driven by the increase in the amount of nitrogen added to agricultural soils, stimulating the N2O-producing nitrification and denitrification processes. Currently there is a poor quantitative understanding of N2O emissions from nitrification and denitrification and their controlling parameters. This is difficult to quantify since N2O emissions from nitrification and denitrification occur simultaneously. As N2O produced from these microbial processes have different stable isotopic signatures, stable isotope measurements have shown promise as a method to partition N2O emissions. Additionally, the intramolecular 15N site preference of N2O presents a further stable isotopic measurement which can be used for studies of N2O emissions from nitrification and denitrification. In this thesis, the absolute intramolecular 15N site preference of N2O measured using high resolution FTIR. The FTIR system was fully calibrated for site preference measurements of 15N enriched N2O sample. In addition, using the FTIR system the absolute site preference value for the N2O working standard used as a reference for isotopic measurements was determined. Using this absolute site preference value, it was possible to determine a value of 19.9 (±2.1)‰ for the absolute site preference of tropospheric N2O. The absolute site preference value of the N2O working standard was used to report measurements of field collected N2O samples on the absolute scale. To determine the intramolecular site preference of N2O produced from nitrification and denitrification, a 2 week field campaign was completed at a dairy farm in south eastern Australia. Soil plots were treated with 15N-labelled NH4 + or NO3 -, either at application rates of 100 or 50 kg-N.ha-1, followed by irrigation. Following treatment, daily measurements were made of the N2O emissions, isotopic composition of N2O, soil mineral nitrogen concentrations and 15N composition, as well as soil moisture. From the interpretation of the collected data, intramolecular site preference signatures of -17 (±5)‰ was determined for nitrification and a range of 0.5 to 12.3‰ was attributed to denitrification. Using the 15N measurements of N2O, it was possible to estimate the N2O emissions produced from nitrification and denitrification. For all treatments, emissions produced from denitrification far outweighed those from nitrification. These measurements indicated that the reduction of N2O to N2 was a key process controlling N2O emissions. Additionally, there was a clear relationship between the intramolecular site preference of N2O, and the amount of N2O reduced to N2. This relationship was used to estimate that for treatments receiving NH4 +, 5 – 22% of the applied nitrogen was emitted as N2.
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Geara, Charif. "Study of the gelation of whey protein isolate by FTIR spectroscopy and rheological measurements." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ50774.pdf.
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Boddy, Ruth Kathleen. "Probing the early events of protein folding using time-resolved step-scan FTIR spectroscopy." Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414210.
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Hsu, Wei-Chun. "Direct and quantitative broadband absorptance micro/nano spectroscopy using FTIR and bilayer cantilever probes." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/78182.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 85-88).
Optical properties of micro/nano materials are important for many applications in biology, optoelectronics, and energy. In this thesis, a method is described to directly measure the quantitative absorptance spectra of micro/nano-sized structures using Fourier Transform Spectroscopy (FTS). The measurement technique combines optomechanical cantilever probes with a modulated broadband light source from an interferometer for spectroscopic measurements of objects. Previous studies have demonstrated the use of bilayer (or multi-layer) cantilevers as highly sensitive heat flux probes with the capability of resolving power as small as ~4 pW. Fourier Transform Spectroscopy is a well-established method to measure broadband spectra with significant advantages over conventional dispersive spectrometers such as a higher power throughput and large signal-to-noise ratio for a given measurement time. By integrating a bilayer cantilever probe with a Michelson interferometer, the new platform is capable of measuring broadband absorptance spectra from 3prm to 18pm directly and quantitatively with an enhanced sensitivity that enables the characterization of micro- and nanometer-sized samples, which cannot be achieved by using conventional spectroscopic techniques. Besides, a paralleled project of a bi-armed cantilever decouples the sample arm and the probe arm to further enhance the signal-to-noise ratio.
by Wei-Chun Hsu.
S.M.