Relevant bibliographies by topics / Thermic and spectroscopic technique

Academic literature on the topic 'Thermic and spectroscopic technique'

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Published: 10 March 2023

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Journal articles on the topic "Thermic and spectroscopic technique"

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K, Niyati. "Thermal Lens Technique as a Potential Optical Tool." International Journal for Research in Applied Science and Engineering Technology 9, no. 11 (November 30, 2021): 918–23. http://dx.doi.org/10.22214/ijraset.2021.38878.

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Abstract: The spectroscopic characterization of materials involves the use of various optical tools. Spectrometers, interferometers etc, are some of the examples of optical tools. Thermal lens technique is one of the potential optical tools for the thermal characterization of different materials. The thermal lens effect is a photothermal effect which results when energy from a laser beam is absorbed by a sample, causing heating of the sample along the beam path. In this paper an overview of thermal lensing, its significance as potential optical tool and its applications are discussed. Index Terms: Optical tool, Photothermal spectroscopy, TLS application, Thermal diffusivity
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Halenka, J., and H. Janus. "An Efficient Spectroscopic Control — Technique of the Parameters of Thermic Plasmas Produced under the Condition of a Variable Current." Beiträge aus der Plasmaphysik 26, no. 1 (1986): 53–56. http://dx.doi.org/10.1002/ctpp.19860260107.

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Alrooqi, Arwa, Zahra M. Al-Amshany, Laila M. Al-Harbi, Tariq A. Altalhi, Moamen S. Refat, Ali M. Hassanien, Gaber A. M. Mersal, and Ahmed A. Atta. "Spectroscopic and Physicochemical Studies on 1,2,4-Triazine Derivative." Coatings 12, no. 5 (May 23, 2022): 714. http://dx.doi.org/10.3390/coatings12050714.

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A novel 5-(5-Bromo-2-hydroxybenzylidene)-6-oxo-3-phenyl-5,6-dihydro-1,2,4-triazine-2(1H)-carbothioamide (4) “compound 4” was synthesized. The chemical structure of compound 4 was confirmed with spectroscopic techniques. Thermal analysis (TGA/dTGA) studies were conducted for identifying the kinetic thermodynamic parameters and the thermal stability of the synthesized compound 4. Cyclic voltammetric studies were performed for recognizing electrochemical characteristics of the synthesized compound 4. The calculated highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), and the band gap were found to be −3.61, −5.32, and 1.97 eV, respectively. Using a diffused reflectance spectroscopy (DRS) technique, the estimated values of the optical band transitions of compound 4 in powder form were found to be 2.07 and 2.67 eV. The structural properties of thermally evaporated compound 4 thin films were analyzed using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. It was found that compound 4 has a triclinic crystal structure. The optical transitions and the optical dispersion factors of compound 4 thin films were investigated using a UV-Vis spectroscopy technique. From the UV-Vis spectroscopy technique, Egind=3.6 V was estimated for both the as-deposited and annealed thin films. For the as-deposited film, there were two photoluminescence (PL) emission peaks centered at 473 and 490 nm with a shoulder at 422 nm. For the annealed film at 423 K, there were five PL emission peaks centered at 274, 416, 439, 464, and 707 nm with a shoulder at 548 nm. The dark electrical conduction of compound 4 thin film was through a thermally activated process with activation energy equaling 0.88 eV.
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Garces, Viviana, Angélica García-Quintero, Tulio A. Lerma, Manuel Palencia, Enrique M. Combatt, and Álvaro A. Arrieta. "Characterization of Cassava Starch and Its Structural Changes Resulting of Thermal Stress by Functionally-Enhanced Derivative Spectroscopy (FEDS)." Polysaccharides 2, no. 4 (November 3, 2021): 866–77. http://dx.doi.org/10.3390/polysaccharides2040052.

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Starch is one of the biopolymers that has been recognized as promising for its application as an eco-friendly substitute for conventional polymers due to its biodegradable nature, low cost, and considerable abundance from renewable vegetal-type resources. In particular, the use of cassava starch as raw material in the manufacture of packaging materials has increased in recent years. Consequently, the analytical study of the quality and features of starch and its derivatives throughout their entire life cycle have gained importance, with non-destructive sample methods being of particular interest. Among these, spectroscopic methods stand out. The aim of this study was evaluated using spectroscopic techniques (i.e., mid-infrared spectroscopy (MIRS) and functional-enhanced derivative spectroscopy (FEDS)) for the monitoring of the effect of the thermal stress of starch in conjunction with computational tools such as density-functional theory (DFT). It is concluded that the FEDS technique in conjunction with DFT calculations can be a useful tool for the high-precision spectral analysis of polymers subjected to small thermal perturbations. In addition, it is demonstrated that small changes produced by thermal stress can be monitored by infrared spectroscopy in conjunction with FEDS at wavenumber range between 3800 and 3000 cm−1, which would allow for the implementation of spectral techniques instead of thermal techniques for out-lab evaluations and for the study of the thermal stress of biomaterials.
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Thomas, R. L., and L. D. Favro. "From Photoacoustic Microscopy to Thermal-Wave Imaging." MRS Bulletin 21, no. 10 (October 1996): 47–52. http://dx.doi.org/10.1557/s088376940003164x.

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Photoacoustic spectroscopy is a technique in which the absorption of periodically intensity-modulated light is detected by the sound that it produces at the (acoustic) modulation frequency in a closed volume of gas or liquid in thermal contact with the material absorbing the light. The spectroscopic aspect of the technique relies on the ability to scan the wavelength of the light that stimulates the sound. Thus one can determine the absorption as a function of wavelength through the conversion of absorbed energy to heat and thence to sound. The acoustic detection is carried out synchronously with respect to the imposed intensity-modulation frequency on the light, making it possible to use narrow-band noise reduction. The existence of this technique for detecting sound generated by the absorption of light led Wong and co-workers to investigate the possibility of using the same techniques for microscopy.
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Caccamo, Maria T., and Antonio Cannuli. "PEG Acoustic Levitation Treatment for Historic Wood Preservation Investigated by Means of FTIR Spectroscopy and Wavelets." Current Chemical Biology 13, no. 1 (February 8, 2019): 60–72. http://dx.doi.org/10.2174/2212796812666180511115839.

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Background: The combination of Fourier Transform InfraRed and levitation techniques, both on levitated water mixtures of Polyethylene Glycols (PEG)s and on wood finds, allows to follow the polymeric drying process as a function of time through the O-H and C-H stretching contributions and to investigate the wood thermal response. Objective: The aim of this paper is to report the FTIR investigations on wood fines, extracted from a 700’ dated wooden crucifix. Methods: At first, different acoustically levitated Polyethylene Glycol (PEG) aqueous solutions were investigated by FTIR in order to characterize the levitation induced dehydration process; then the wood fines, after having been treated by immerging them into the PEG aqueous solutions, were acoustically levitated and investigated; finally the treated fines were again studied by IR spectroscopy through a thermic cycle in the 25 ÷ 350 °C temperature range. Levitation technique furnishes an innovative approach to sample treatment allowing, in the case of solutions, to obtain highly concentrated mixtures starting from diluted solutions while, in the case of wood find treatments, to increase the polymer solution penetration within the wood matrix. Results: It clearly emerges that, in the PEG200/PEG600 comparison, the lighter polymer shows a higher effectiveness in terms of thermal restraint. Conclusion: Acoustic levitation, in combination with IR spectroscopy, reveals to be a very powerful technique in many applications concerning wood preservation and conservation. It clearly emerges that, in the comparison with PEG600, PEG200 shows a higher effectiveness in terms of thermal restraint.
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Li, Bingcheng, Yanzhuo Deng, and Jieke Cheng. "Pulsed Photothermal Deflection Spectroscopy with Optically Dense Samples." Applied Spectroscopy 49, no. 3 (March 1995): 279–85. http://dx.doi.org/10.1366/0003702953963436.

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The pulsed photothermal deflection spectroscopy (PTDS) method to determine the large optical absorption coefficient from the transverse PTDS magnitude and to measure spectroscopic data of optically dense sample from the normal-to-transverse magnitude ratio of the PTDS signal is presented and has been examined both theoretically and experimentally. Saturation at high absorption, effects of thermal inhomogeneity of the sample, and energy or power fluctuation of both the excitation and probe beams are avoided by this method. Together with the transverse PTDS technique, the dynamic range of spectroscopic measurement is over 9 to 10 orders of magnitude. This technique can be used with sample which is transparent or semitransparent to the probe beam.
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Hassoun, Abdo, Karsten Heia, Stein-Kato Lindberg, and Heidi Nilsen. "Spectroscopic Techniques for Monitoring Thermal Treatments in Fish and Other Seafood: A Review of Recent Developments and Applications." Foods 9, no. 6 (June 10, 2020): 767. http://dx.doi.org/10.3390/foods9060767.

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Cooking is an important processing method, that has been used since ancient times in order to both ensure microbiological safety and give desired organoleptic properties to the cooked food. Fish and other seafood products are highly sensitive to thermal treatments and the application of severe heat can result in negative consequences on sensory and nutritional parameters, as well as other quality attributes of the thermally processed products. To avoid such undesired effects and to extend the shelf life of these perishable products, both the heat processing methods and the assessment techniques used to monitor the process should be optimized. In this review paper, the most common cooking methods and some innovative ones will first be presented with a brief discussion of their impact on seafood quality. The main methods used for monitoring heat treatments will then be reviewed with a special focus on spectroscopic techniques, which are known to be rapid and non-destructive methods compared to traditional approaches. Finally, viewpoints of the current challenges will be discussed and possible directions for future applications and research will be suggested. The literature presented in this review clearly demonstrates the potential of spectroscopic techniques, coupled with chemometric tools, for online monitoring of heat-induced changes resulting from the application of thermal treatments of seafood. The use of fluorescence hyperspectral imaging is especially promising, as the technique combines the merits of both fluorescence spectroscopy (high sensitivity and selectivity) and hyperspectral imaging (spatial dimension). With further research and investigation, the few current limitations of monitoring thermal treatments by spectroscopy can be addressed, thus enabling the use of spectroscopic techniques as a routine tool in the seafood industry.
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Kwietniewski, N., Krystyna Gołaszewska, T. T. Piotrowski, W. Rzodkiewicz, Tomasz Gutt, M. Sochacki, Jan Szmidt, and Anna Piotrowska. "Oxidation Process of SiC by RTP Technique." Materials Science Forum 615-617 (March 2009): 529–32. http://dx.doi.org/10.4028/www.scientific.net/msf.615-617.529.

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The kinetics of 4H-SiC thermal oxidation by RTP technique and the properties of thin thermal oxide was reported. The thickness of the thermal oxide was determined by spectroscopic ellipsometry and confirmed by electrical measurements. The conductance method was applied to analyse the surface states parameters. The lifetime, density and cross-section of the surface traps were extracted for as-fabricated MOS capacitors and after thermal annealing processes.
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Thomas, Jeena, Prakash Perikaruppan, Vinoy Thomas, Jancy John, Raji Mary Mathew, Joice Thomas, Ibrahimkutty Rejeena, Sebastian Mathew, and Abdulhassan Mujeeb. "Green Synthesized Plasmonic Silver Systems for Potential Non-Linear Optical Applications: Optical Limiting and Dual Beam Mode Matched Thermal Lensing." Australian Journal of Chemistry 72, no. 6 (2019): 460. http://dx.doi.org/10.1071/ch18617.

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Bioactive compound functionalized plasmonic systems are evolving as a promising branch of nanotechnology. In this communication the synthesis of bioactive compound mimosine-based silver nanoparticles (AgNPs) and their non-linear optical and thermo-optic properties are presented. UV-Visible spectroscopy, optical bandgap measurement, fluorescence spectroscopy, and high-resolution transmission electron microscopy (HRTEM) techniques were used to characterize the synthesized AgNPs. An open aperture z-scan technique was used to determine the non-linear optical parameters. A very strong reverse saturable absorption (RSA) and low optical limiting threshold were observed for the present mimosine decorated AgNP system. The thermo-optic property of the present system was evaluated using a highly sensitive dual beam mode matched thermal lensing spectroscopic technique. A comparison of the low limiting threshold (242MWcm−2) and thermo-optic property (thermal diffusivity, D=1.13×10−7m2s−1) with similar systems proves its capability for non-linear optical and thermo-optic applications.
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Dissertations / Theses on the topic "Thermic and spectroscopic technique"

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Natarajan, Shweta. "Thermal metrology techniques for ultraviolet light emitting diodes." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45891.

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AlₓGa₁₋ₓN (x>0.6) based Ultraviolet Light Emitting Diodes (UV LEDs) emit in the UV C range of 200 - 290 nm and suffer from low external quantum efficiencies (EQEs) of less than 3%. This low EQE is representative of a large number of non-radiative recombination events in the multiple quantum well (MQW) layers, which leads to high device temperatures due to self-heating at the device junction. Knowledge of the device temperature is essential to implement and evaluate appropriate thermal management techniques, in order to mitigate optical degradation and lifetime reduction due to thermal overstress. The micro-scale nature of these devices and the presence of large temperature gradients in the multilayered device structure merit the use of several indirect temperature measurement techniques to resolve device temperatures. This work will study UV LEDs with AlₓGa₁₋ₓN active layers, grown on sapphire or AlN growth substrates, and flip-chip mounted onto submounts and package configurations with different thermal properties. Thermal metrology results will be presented for devices with different electrode geometries (i.e., interdigitated and micropixel), for bulk and thinned growth substrates. The body of this work will present a comparative study of optical techniques such as Infrared (IR), micro-Raman and Electroluminescence (EL) spectroscopy for the thermal metrology of UV LEDs. The presence of horizontal and vertical temperature gradients within the device layers will be studied using micro-Raman spectroscopy, while the occurrence of thermal anomalies such as hotspots and shorting paths will be studied using IR spectroscopy. The Forward Voltage (Vf) method, an electrical junction temperature measurement technique, will also be investigated. The Vf method will be applied to the Thermal Resistance Analysis by Induced Transient (TRAIT) procedure, whereby electrical data at short time scales from an operational device will be used to discretize the junction-to- package thermal resistance pathway from the total junction- to-ambient heat path. The TRAIT procedure will be conducted on several LEDs, for comparison. The scope and applicability of each thermal metrology technique will be examined, and the merits and demerits of each technique will be exhibited.
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Appadoo, Dominique R. T. (Dominique Rupert Thierry) 1964. "Spectral simplification techniques for high resolution fourier transform spectroscopic studies." Monash University, School of Chemistry, 2002. http://arrow.monash.edu.au/hdl/1959.1/7746.

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Piskorz, Danielle, Björn Benneke, Nathan R. Crockett, Alexandra C. Lockwood, Geoffrey A. Blake, Travis S. Barman, Chad F. Bender, John S. Carr, and John A. Johnson. "Detection of Water Vapor in the Thermal Spectrum of the Non-transiting Hot Jupiter Upsilon Andromedae b." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/625300.

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The Upsilon Andromedae system was the first multi-planet system discovered orbiting a main-sequence star. We describe the detection of water vapor in the atmosphere of the innermost non-transiting gas giant ups. And. b by treating the star-planet system as a spectroscopic binary with high-resolution, ground-based spectroscopy. We resolve the signal of the planet's motion and break the mass-inclination degeneracy for this non-transiting planet via deep combined flux observations of the star and the planet. In total, seven epochs of Keck NIRSPEC L band observations, three epochs of Keck NIRSPEC short-wavelength K band observations, and three epochs of Keck NIRSPEC long wavelength K band observations of the ups. And. system were obtained. We perform a multi-epoch cross-correlation of the full data set with an atmospheric model. We measure the radial projection of the Keplerian velocity (K-P = 55 +/- 9 km s(-1)), true mass (M-b = 1.7(-0.24)(+0.33)M(J)), and orbital inclination (i(b) 24 degrees +/- 4 degrees), and determine that the planet's opacity structure is dominated by water vapor at the probed wavelengths. Dynamical simulations of the planets in the ups. And. system with these orbital elements for ups. And. b show that stable, long-term (100 Myr) orbital configurations exist. These measurements will inform future studies of the stability and evolution of the ups. And. system, as well as the atmospheric structure and composition of the hot Jupiter.
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Piskorz, Danielle, Björn Benneke, Nathan R. Crockett, Alexandra C. Lockwood, Geoffrey A. Blake, Travis S. Barman, Chad F. Bender, et al. "EVIDENCE FOR THE DIRECT DETECTION OF THE THERMAL SPECTRUM OF THE NON-TRANSITING HOT GAS GIANT HD 88133 b." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/622450.

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We target the thermal emission spectrum of the non-transiting gas giant HD 88133 b with high-resolution near-infrared spectroscopy, by treating the planet and its host star as a spectroscopic binary. For sufficiently deep summed flux observations of the star and planet across multiple epochs, it is possible to resolve the signal of the hot gas giant's atmosphere compared to the brighter stellar spectrum, at a level consistent with the aggregate shot noise of the full data set. To do this, we first perform a principal component analysis to remove the contribution of the Earth's atmosphere to the observed spectra. Then, we use a cross-correlation analysis to tease out the spectra of the host star and HD 88133 b to determine its orbit and identify key sources of atmospheric opacity. In total, six epochs of Keck NIRSPEC L-band observations and three epochs of Keck NIRSPEC K-band observations of the HD 88133 system were obtained. Based on an analysis of the maximum likelihood curves calculated from the multi-epoch cross-correlation of the full data set with two atmospheric models, we report the direct detection of the emission spectrum of the non-transiting exoplanet HD 88133 b and measure a radial projection of the Keplerian orbital velocity of 40 +/- 15 km s(-1), a true mass of 1.02(-0.28)(+0.61) M-J, a nearly face-on orbital inclination of 15(-5)(+60), and an atmosphere opacity structure at high dispersion dominated by water vapor. This, combined with 11 years of radial velocity measurements of the system, provides the most up-to-date ephemeris for HD 88133.
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Grisedale, Louise Clare. "The Development of Thermal and Spectroscopic Characterisation Techniques for the Study of Amorphous Pharmaceutical Materials." Thesis, University of East Anglia, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.514322.

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In recent years there has been an increased interest in the use of amorphous materials in the pharmaceutical industry because of their enhanced thermodynamic properties owing to their greater molecular mobility. Pharmaceutically, formulating with an amorphous material can improve the dissolution and bioavailability of a drug. It can also be used in the stabilisation of another formulation component. However, any potential benefits of an amorphous pharmaceutical are counterbalanced by their metastable nature and tendency to recrystallise spontaneously to their, more stable, crystalline state. The work presented here details the development of thermal and spectroscopic characterisation techniques to study pharmaceutical materials in partially and fully amorphous states. This thesis focuses on the characterisation of a single pharmaceutical material, salbutamol sulphate, nevertheless the experimental research involved highlights the complexities of a "real" amorphous material. Throughout this work numerous difficulties were encountered in characterising the amorphous phase. Specifically the close proximity of the decomposition temperature of amorphous salbutamol sulphate to its glass transition temperature proved eventful and differences seen in both the recrystallisation kinetics and physical stability associated with the preparation method were intriguing. In general, the interaction of water with the amorphous phase further complicates its behaviour. Progress was made towards understanding this relationship and this work has identified and detailed several questions and possible future areas of research. Of the newly developed techniques to study amorphous materials, photothermal microspectroscopy was identified as having the potential to differentiate morphological, chemical and physical differences spatially between the amorphous and crystalline forms. Thermally stimulated current spectroscopy was, however, found to be less reliable at determining the relaxation behaviour of the amorphous sample. To conclude, the research carried out and detailed within this thesis used existing and newly developed thermal and spectroscopic characterisation techniques to further our understanding of amorphous materials and their associated complexities.
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Schueler, Robert M. "Terahertz Spectroscopic Breath Analysis as a Viable Analytical Chemical Sensing Technique." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1464170300.

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Smith, Paul. "Sharp Polarimetric Eyes: More Trees than Forest?" MDPI AG, 2016. http://hdl.handle.net/10150/621985.

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The Fermi Gamma-ray Space Telescope (Fermi) has focused the intensive multi-wavelength and international observational effort on blazars since it was launched in 2008. Part of this effort involves systematic monitoring of the highly variable polarization of the continuum emission from these objects. These observations are valuable in that they provide direct information on the degree of ordering and orientation on the sky of the magnetic field within the non-thermal emission region(s). Unfortunately, it is not yet possible to measure the polarization of the inverse-Compton continuum, only that of the lower-energy synchrotron emission. The inability to directly compare the polarization of the two dominant continuum sources in blazars is a drawback and leads to more ambiguities in determining their relative locations. There are many compelling examples of strong connections between -ray, X-ray, UV/optical/IR, and radio behavior in blazars that suggest the same region produces much of the observed emission at all wavelengths at least some of the time. However, the wealth of polarization behavior seen relative to flux changes invariably results in a complex situation that is difficult to interpret and model. The long-term blazar monitoring program undertaken at Steward Observatory is designed to primarily obtain accurate optical polarimetry of -ray-bright blazars during the Fermi mission with the goal of gaining important insights into the jet structure and physics of these objects. Data from this program are available to all researchers as soon as reductions are completed. I briefly detail the current status and progress of the program and the data products available. Although the wide variety of polarization behavior in blazars adds another layer of complexity to an already difficult problem, I summarize several important conclusions that can be drawn from the polarization information gathered during the Fermi era.
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Venumuddala, Hareesha Reddy. "Study of Drug Delivery Behavior Through Biomembranes Using Thermal And Bioanalytical Techniques." Cleveland State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=csu1295472144.

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Kolbe, G. "Three level spectroscopic technique applied to collision rate and line shape determination in a plasma." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37746.

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Bostrom, Gregory A. "Development of a Portable Cavity Ring-Down Spectroscopic Technique for Measuring Stable Isotopes in Atmospheric Methane." PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/51.

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Trace gases can have a significant impact on the Earth's climate, and the analysis of changes in these gases and an understanding of how much of these changes are a result of human activity is important for understanding global climate change. Methane (CH4) is the second only to CO2 in radiative forcing over the last 200 years, and its concentration in the atmosphere has more than doubled since 1750. Sources and sinks of CH4 have characteristic isotopic effects, which shift the relative concentration of the methane isotopologues. Spectroscopic techniques for of analysis the isotopic composition of methane have been evolving since the early 1990's, and promise real-time, in-situ measurements that would provide unprecedented information on the methane atmospheric cycle. Here we present our development and results of a new optical spectroscopic isotope ratio instrument using cavity ringdown spectroscopy in the near IR region using the ν2+2ν3 overtone band. This region has limited interference from other molecules, and an advantageous juxtaposition of a 13CH4 triplet, and a single 12CH4 peak, allowing near-simultaneous measurement of both isotopologues. We present the results of two datasets showing high linearity over a wide range of isotope ratios, which achieved a precision of ±4 /. We present analysis of the data and consider the effects of temperature and molecular interference.
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Books on the topic "Thermic and spectroscopic technique"

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Beth, Opila, and NASA Glenn Research Center, eds. Investigation into spectroscopic techniques for thermal barrier coating spall detection. [Cleveland, Ohio]: National Aeronautics and Space Administration, Glenn Research Center, 2001.

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1939-, Provder Theodore, Urban Marek W. 1953-, Barth Howard G, American Chemical Society. Division of Polymeric Materials: Science and Engineering., American Chemical Society. Division of Analytical Chemistry., and American Chemical Society Meeting, eds. Hyphenated techniques in polymer characterization: Thermal-spectroscopic and other methods. Washington, DC: American Chemical Society, 1994.

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M, Loew Leslie, ed. Spectroscopic membrane probes. Boca Raton, Fla: CRC Press, 1988.

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J, McNamara Bernard, Lerner Jeremy M, University of New Mexico, Society of Photo-optical Instrumentation Engineers., and American Astronomical Society, eds. Optical spectroscopic instrumentation and techniques for the 1990s: Applications in astronomy, chemistry, and physics, 4-6 June 1990, Las Cruces, New Mexico. Bellingham, Wash: SPIE, 1990.

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Jinxue, Wang, Hays Paul B, and Society of Photo-optical Instrumentation Engineers., eds. Optical spectroscopic techniques and instrumentation for atmospheric and space research II: 5-6 August 1996, Denver, Colorado. Bellingham, Wash: SPIE, 1996.

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M, Larar Allen, and Society of Photo-optical Instrumentation Engineers., eds. Optical spectroscopic techniques and instrumentation for atmospheric and space research III: 19-21 July 1999, Denver, Colorado. Bellingham, Wash: SPIE, 1999.

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1944-, Denton M. Bonner, and Royal Society of Chemistry (Great Britain), eds. Further developments in scientific optical imaging. Cambridge: Royal Society of Chemistry, 2000.

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M, Larar Allen, Mlynczak Martin G, Langley Research Center, and Society of Photo-optical Instrumentation Engineers., eds. Optical spectroscopic techniques, remote sensing, and instrumentation for atmospheric and space research IV: 30 July-2 August 2001, San Diego, USA. Bellingham, Wash: SPIE, 2002.

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Michael, Cox, Srinivasan Vijayakumar, and United States. National Aeronautics and Space Administration., eds. Development of processing techniques for advanced thermal protection materials: (NASA-Ames grant no. NAG2-848) : semi-annual progress report : June 1, 1997-November 30, 1997. [Washington, DC: National Aeronautics and Space Administration, 1997.

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United States. National Aeronautics and Space Administration., ed. Development of processing techniques for advanced thermal protection materials: Annual report for the period June 1, 1993 through May 31, 1994. [Washington, DC: National Aeronautics and Space Administration, 1994.

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Book chapters on the topic "Thermic and spectroscopic technique"

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Collins, Robert W. "Measurement Technique of Ellipsometry." In Spectroscopic Ellipsometry for Photovoltaics, 19–58. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-75377-5_2.

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Meyer-Vernet, Nicole, Sang Hoang, Karine Issautier, Milan Maksimovic, Robert Manning, Michel Moncuquet, and Robert G. Stone. "Measuring plasma parameters with thermal noise spectroscopy." In Measurement Techniques in Space Plasmas: Fields, 205–10. Washington, D. C.: American Geophysical Union, 1998. http://dx.doi.org/10.1029/gm103p0205.

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Cao, Bingqiang, Haibo Gong, Haibo Zeng, Weiping Cai, Kaushal Kumar, Luigi Sanguigno, Filippo Causa, Paolo Antonio Netti, and Yashashchandra Dwivedi. "Photolumniscence/Fluorescence Spectroscopic Technique for Nanomaterials Characterizations." In Nanomaterials, 555–620. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2012. http://dx.doi.org/10.1002/9783527646821.ch9.

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Thomas, Robert J. "What Atomic Spectroscopic Technique Is Right for Your Lab?" In Measuring Heavy Metal Contaminants in Cannabis and Hemp, 377–86. First edition. | Boca Raton : Taylor and Francis, 2020.: CRC Press, 2020. http://dx.doi.org/10.1201/9781003004158-28.

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Robert, Thomas. "What Atomic Spectroscopic Technique is Right for Your Lab?" In Measuring Elemental Impurities in Pharmaceuticals, 321–34. Boca Raton : Taylor & Francis, 2018. | Series: Practical spectroscopy ; [v. 40]: CRC Press, 2018. http://dx.doi.org/10.1201/b21952-23.

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Allen, G. M., and K. F. Drain. "Comparison of Thermal, Mechanical, and Spectroscopic Techniques for Characterization of Radiation-Cured Adhesives." In ACS Symposium Series, 242–57. Washington, DC: American Chemical Society, 1990. http://dx.doi.org/10.1021/bk-1990-0417.ch018.

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Beltran, Shirley Susana Cruz, Zasha Vazquez-Colon, Torrey D. Baines, and Kevin J. Sullivan. "Central Nervous System Near-Infrared Spectroscopic Monitoring: Technique and Clinical Application." In Koht, Sloan, Toleikis's Monitoring the Nervous System for Anesthesiologists and Other Health Care Professionals, 227–63. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-09719-5_11.

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Kapadia, A. J. "Neutron Stimulated Emission Computed Tomography: A New Technique for Spectroscopic Medical Imaging." In Neutron Imaging and Applications, 265–88. Boston, MA: Springer US, 2009. http://dx.doi.org/10.1007/978-0-387-78693-3_15.

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Yang, J. C., S. Bradley, M. Yeadon, and J. M. Gibson. "Nano-sized metal clusters investigated by a STEM-based mass spectroscopic technique." In Electron Microscopy and Analysis 1997, 383–86. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003063056-99.

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Borchers, W., E. Arnold, W. Neu, R. Neugart, G. Ulm, and K. Wendt. "A New Sensitive Technique for Laser Spectroscopic Studies of Radioactive Rare-Gas Isotopes." In Laser Spectroscopy VIII, 176–77. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-540-47973-4_45.

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Conference papers on the topic "Thermic and spectroscopic technique"

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Svaasand, L. O., E. J. Fiskerstrand, L. T. Norvang, J. S. Nelson, and M. W. Berns. "Spectroscopic Techniques for Diagnosis and Evaluation of Therapeutic Response." In Lasers in Dermatology: Bio-Optics and Treatment of Human Skin. Washington, D.C.: Optica Publishing Group, 1997. http://dx.doi.org/10.1364/lid.1997.fa3.

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Several optical methods have proved useful as a diagnostic tool for characterizing various skin disorders. The techniques vary from non-coherent methods such as, e.g., time independent reflectance spectroscopy and phase resolved photon migration based on evaluating the phase of the envelope of a high frequency amplitude modulated optical beam. A typical example a coherent or interferometric technique is optical coherence tomography where the spatial resolution is determined by the small coherence length a superluminescent diode source. Various infrared or thermal techniques are also important, ranging from imaging of the normal black body emission to time resolved measurements of the surface temperature initiated by transient selective heating of subcutaneous structures, such as, e.g., blood vessels.1-3)
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Gautam, Vivek, and A. K. Gupta. "Spectroscopic Analysis of Fuel Lean Flames for Propulsion Applications." In ASME 2004 Power Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/power2004-52074.

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Chemiluminescence and thermal imaging techniques have been used to examine the chemical and thermal behavior of turbulent flames with practical application to TBCC propulsion systems. The present study examines single swirler using an experimental double concentric swirl burner that simulates one swirler in a practical gas turbine combustor. The optical emission spectroscopy (OES) technique have been used to provide information on selected species in flames that mark the flame reaction zone and heat release rate. The instantaneous images are then integrated to obtain time-averaged information. Spatial distribution of OH, CH, C2 species from within the flames have been obtained at selected wavelengths using an ICCD camera and narrow band interference filters. The vibrational temperature distributions are obtained from the ratio of intensities of two discrete C2 bands of 470nm and 515nm. The time-averaged spatial distribution of flame generated radicals is processed using the Abel Inversion technique to project the initial 2-D image to represent the 3-D distribution of species and temperature in the flame. The results show that swirl distribution affects the shape of the spatial distribution by spreading the high intensity regions radially outwards with increase in swirl strength at inner regions of the fuel injector. Co-swirl distribution in the burner provided decrease in temperature and species intensity due to greater entrainment of the surrounding fluid. Calculated flame thermal strain rates were found to be significantly different for the co- and counter-swirl flames.
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Iijima, Akira, and Hideo Shoji. "A Spectroscopic Analysis of Combustion in Homogeneous Charge Compression Ignition Engine." In ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference collocated with the ASME 2007 InterPACK Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ht2007-32552.

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The principal issues of Homogeneous Charge Compression Ignition (HCCI) combustion that must be addressed include ignition timing control and expansion of the stable operation region. Detailed analyses of ignition and combustion mechanisms must be undertaken to resolve these issues. In this study, spectroscopic technique was used to investigate the effects of the air-fuel ratio (AFR) and residual gas state on ignition and combustion characteristics. Spectroscopic measurement was made of light emission spectra. The results revealed that the distribution profile of the light emission intensity of the hot flame differed substantially depending on the air-fuel ratio (AFR). In high AFR condition, a continuous spectrum attributed to carbon monoxide-oxygen (CO-O) glow is seen between 300–500 nm, but there is no strong light emission such as that from the OH radical. However, decreasing the AFR, a strong light emission is seen a little after the CO-O glow in a wavelength range from visible light to the near-infrared region (500–850 nm). It is also clear that increasing the internal EGR declined the cool flame magnitude, which substantially altered the ignition characteristics of HCCI combustion. Specifically, when a low-octane fuel was used, the heat release rate waveform for HCCI combustion showed two-stage ignition, which was clearly observed in the light emission spectra.
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Ghaderi, M., and A. K. Gupta. "Spectroscopic Analysis of Diffusion Flame Using High Temperature Combustion Air." In ASME 2004 Power Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/power2004-52179.

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Results are presented on the effect of high temperature combustion air on the thermal and chemical behavior of propane-air diffusion flames using spectroscopic diagnostic techniques. The oxygen concentration in air was 21% by volume for both the normal and highly preheated air flames. The temperature distribution within the flames has been obtained for a burning fuel jet using normal temperature and high temperature combustion air. Spatial distribution of C2, CH and OH from within the flames in 2-D has been obtained. An ICCD (image intensified charge coupled device) camera fitted with an appropriate narrow band interference filter provided the spontaneous emission signature of the specific specie produced in the flame. The results show that the intensity level of C2 in the flame with highly preheated air is lower than the corresponding normal temperature air flames. In contrast the intensity level of CH radicals in the flame is higher than corresponding normal air temperature flames. The intensity level of OH radicals with highly preheated air is higher than corresponding normal temperature air flames. They suggest faster chemical reaction and higher heat release rate with high temperature combustion air than the corresponding normal temperature air. These findings are much different than those obtained for low oxygen concentration air flames. The Abel transformation technique was applied to obtain 3-D spatial distribution of selected radicals within the flames. Two emission peaks of C2 radical species have been observed in the visible part of the wavelength. The temperature distribution inside the flame was obtained from the ratio of these two peaks using two-color method. The effect of preheated combustion air on the flame temperature has been determined by analyzing the spectra of spontaneous emission of the C2 radicals at two discrete wavelengths.
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Peters, V., L. Fornasiero, E. Mix, A. Diening, K. Petermann, and G. Huber. "Spectroscopic characterization and diode-pumped laser action at 2.7μm of Er:Lu2O3." In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1998. http://dx.doi.org/10.1364/cleo_europe.1998.cff10.

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The sesquioxide Lu2O3 (Lutetia) is isostructural to the comparatively well examined Y2O3 (Yttria). Therefore the thermal conductivity of Lutetia is assumed to be in the same high range as in Yttria (27 W/mK [1]), which makes Lutetia an interesting host material for high power lasing. Due to its high melting point (around 2500°C) is was impossible to grow Lutetia from crucibles in the past so that size and optical quality of existing samples were limited. We have, for the first time to our knowledge, grown Lutetia doped with RE3+-ions from rhenium crucibles using the Nacken-Kyropoulos technique. First samples show monocrystalline regions with rather low stress induced birefringence.
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Eckart, Sven, Ralph Behrend, and Hartmut Krause. "Microwave influenced laminar premixed hydrocarbon flames: Spectroscopic investigations." In Ampere 2019. Valencia: Universitat Politècnica de València, 2019. http://dx.doi.org/10.4995/ampere2019.2019.9834.

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Low laminar burning velocity’s and slow reactions propagation are among a key problem in combustion processes with low calorific gas mixtures. The mixtures have a laminar burning velocity of 10 cm/s to 15 cm/s or even below which is 37% of natural gas. Thermal use of these gases could save considerable amounts of fossil fuel and reduce CO2 emissions. Due to low burning velocities and low enthalpy of combustion, ignition and stable combustion is complex, often preventing utilization of these gases. Microwave-assisted combustion can help to solve these problems. With microwave assistance, these gas mixtures could be burned with a higher burning velocity without preheating or co-firing. Therefore, this effect could be used for flame stabilization processes in industry applications. Microwaves could also change the combustion properties, for example radical formation and flame thickness. In this paper, we explore a possibility of using microwaves to increase the burning velocity of propane as one component in low calorific gas mixtures and also show higher productions of OH* and CH* radicals with an increase of the input microwave power. Different compositions of low calorific fuels were tested within a range of equivalence ratios from φ= 0.8 to φ= 1.3 for initial temperatures of 298 K and atmospheric conditions and microwave powers from 120 W to 600 W. For the experiments, a standard WR340 waveguide was modified with a port for burner installation and filter elements allowing for flue gas exhaust and optical access from the side. A 2.45 GHz CW magnetron was used as microwave source, microwave measurements were carried out with a 6-port- reflectometer with integrated three stub tuner. An axisymmetric premixed burner was designed to generate a steady conical laminar premixed flame stabilized on the outlet of a contoured nozzle under atmospheric pressure. The burner was operated with a propane mass flow of 0.2-0.4 nl/min at an equivalence ratio of φ= 0.8 to φ= 1.3. The optical techniques used in the current study are based on the flame contours detection by using the OH* chemiluminescence image technique. For every experimental case, 150 pictures were taken and averaged. Additionally, spectroscopic analysis of the flames was undertaken. The results suggest that production of OH* radicals in the flame front increases with microwave power. For evaluation, a picture based OH* chemiluminescence and a spectrographic method was used. In addition, a 9.9% increase of the burning velocity was observed in the premixed propane-air mixture for a 66 Watt absorbed microwave power. This effect is attributed to the increased OH* (~310nm) and CH* (~420nm) radical formation, which also reduces the flame thickness. It was found that absorption of microwaves in flames is generally low, but could be improved by a customized applicator design.
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Das, Saborni, Abhik Hazra, Mousumi Basu, and Ashish Laddha. "Optimized hydel-thermic operative outlining using grey-wolf optimizing technique." In 2017 IEEE International Conference on Power, Control, Signals and Instrumentation Engineering (ICPCSI). IEEE, 2017. http://dx.doi.org/10.1109/icpcsi.2017.8392015.

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Twieg, Robert J., D. Burland, K. Carter, C. Moylan, J. Hedrick, R. D. Miller, M. Staehelin, P. Walsh, and W. Volksen. "Progress in optimization of the magnitude and stability of nonlinearity in poled polymers." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/oam.1992.tua4.

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General issues related to the design and optimization of second order nonlinear optical chromophores and polymers are presented and exemplified by recent work. Nonlinear chromophores have been prepared that contain only thermally stable functionality, their optical nonlinearities β and βo have been evaluated by the EFISH technique, and their thermal stability has been evaluated by a combination of thermogravitimetric, calorimetric, and spectroscopic techniques. These special chromophores have been incorporated into high temperature thermoplastics in both guest/host and covalent configurations, and the anisotropic polar order in thin films of these materials is created by electric field poling (corona or electrode). The magnitude of the optical nonlinearity and the stability at elevated temperatures (>200°C) is evaluated, and the materials design and processing features required for minimization of the relaxation of polar order are described.
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Fukuda, Takeshi, Takashi Takata, Hiroshi Horiike, Nobuyuki Kimura, and Hideaki Kamide. "Direct Observation and Control of Liquid Sodium Flow Dynamics Using VUV-LIF-PIV Technique Under EXB Lorentz Force." In 18th International Conference on Nuclear Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/icone18-29671.

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Based on a heuristic hypothesis that alkaline metals with one single electron on the outermost shell would little interact with externally applied RF field above plasma frequency, a rudimentary experiment as well as the theoretical estimate of the energy structure been performed to further explore the spectroscopic properties of liquid sodium (Na)[1–3]. Consequently, it was successfully proven that Na is reasonably transparent to the VUV (vacuum ultraviolet) laser radiation, although the liquid Na surface is highly reflective, being like a mirror to human eyes. The impact of this result is that the velocity field information inside the liquid Na can be visualized by implementing the well developed PIV (particle image velocimetry) technique[4, 5]. A large eddy simulation (LES) code has also been developed for comparison with the experimental results[6]. Furthermore, the newly developed Na loop is designed so as to enable the application of electric and magnetic field in the orthogonal direction to each other that vigorous dynamics of vortices inside the liquid Na are resolved in the phase space under the Lorentz force. The results herein obtained contribute not only to the thermal hydraulics in fast reactors[7, 8] but also space physics, such as the spiral galaxy formation[9] and solar flare activities[10].
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Holliday, Keith, Mauro Croci, Eric Vauthey, and Urs P. Wild. "Spectral Hole-Burning and Holography in a Y2SiO5:Pr3+ Crystal." In Spectral Hole-Burning and Luminescence Line Narrowing: Science and Applications. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/shbl.1992.tua4.

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Plane wave holography is a method of producing and detecting weak spectral holes with very low background [1]. Its success relies upon hole-burning materials of excellent optical quality with strongly absorbing zero phonon lines such as dye doped polymers which have been extensively studied [2 and references therein]. Through an extension of this technique, image storage [3] and data manipulation [4] have been demonstrated in such materials. Here, we report the application of plane wave holography to a crystalline material, Y2SiO5:Pr3+, for the first time. Spectroscopic measurements of Y2SiO5:Pr3+ have not previously been reported.
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Reports on the topic "Thermic and spectroscopic technique"

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Yakovlev, V. A., and E. A. Irene. An Interface Enhanced Spectroscopic Ellipsometry Technique: Application to Si-SiO2. Fort Belvoir, VA: Defense Technical Information Center, November 1991. http://dx.doi.org/10.21236/ada242867.

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Tutt, T. E. X-ray spectroscopic technique for energetic electron transport studies in short-pulse laser/plasma interactions. Office of Scientific and Technical Information (OSTI), December 1994. http://dx.doi.org/10.2172/96647.

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Bostrom, Gregory. Development of a Portable Cavity Ring-Down Spectroscopic Technique for Measuring Stable Isotopes in Atmospheric Methane. Portland State University Library, January 2000. http://dx.doi.org/10.15760/etd.51.

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Irudayaraj, Joseph, Ze'ev Schmilovitch, Amos Mizrach, Giora Kritzman, and Chitrita DebRoy. Rapid detection of food borne pathogens and non-pathogens in fresh produce using FT-IRS and raman spectroscopy. United States Department of Agriculture, October 2004. http://dx.doi.org/10.32747/2004.7587221.bard.

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Rapid detection of pathogens and hazardous elements in fresh fruits and vegetables after harvest requires the use of advanced sensor technology at each step in the farm-to-consumer or farm-to-processing sequence. Fourier-transform infrared (FTIR) spectroscopy and the complementary Raman spectroscopy, an advanced optical technique based on light scattering will be investigated for rapid and on-site assessment of produce safety. Paving the way toward the development of this innovative methodology, specific original objectives were to (1) identify and distinguish different serotypes of Escherichia coli, Listeria monocytogenes, Salmonella typhimurium, and Bacillus cereus by FTIR and Raman spectroscopy, (2) develop spectroscopic fingerprint patterns and detection methodology for fungi such as Aspergillus, Rhizopus, Fusarium, and Penicillium (3) to validate a universal spectroscopic procedure to detect foodborne pathogens and non-pathogens in food systems. The original objectives proposed were very ambitious hence modifications were necessary to fit with the funding. Elaborate experiments were conducted for sensitivity, additionally, testing a wide range of pathogens (more than selected list proposed) was also necessary to demonstrate the robustness of the instruments, most crucially, algorithms for differentiating a specific organism of interest in mixed cultures was conceptualized and validated, and finally neural network and chemometric models were tested on a variety of applications. Food systems tested were apple juice and buffer systems. Pathogens tested include Enterococcus faecium, Salmonella enteritidis, Salmonella typhimurium, Bacillus cereus, Yersinia enterocolitis, Shigella boydii, Staphylococus aureus, Serratiamarcescens, Pseudomonas vulgaris, Vibrio cholerae, Hafniaalvei, Enterobacter cloacae, Enterobacter aerogenes, E. coli (O103, O55, O121, O30 and O26), Aspergillus niger (NRRL 326) and Fusarium verticilliodes (NRRL 13586), Saccharomyces cerevisiae (ATCC 24859), Lactobacillus casei (ATCC 11443), Erwinia carotovora pv. carotovora and Clavibacter michiganense. Sensitivity of the FTIR detection was 103CFU/ml and a clear differentiation was obtained between the different organisms both at the species as well as at the strain level for the tested pathogens. A very crucial step in the direction of analyzing mixed cultures was taken. The vector based algorithm was able to identify a target pathogen of interest in a mixture of up to three organisms. Efforts will be made to extend this to 10-12 key pathogens. The experience gained was very helpful in laying the foundations for extracting the true fingerprint of a specific pathogen irrespective of the background substrate. This is very crucial especially when experimenting with solid samples as well as complex food matrices. Spectroscopic techniques, especially FTIR and Raman methods are being pursued by agencies such as DARPA and Department of Defense to combat homeland security. Through the BARD US-3296-02 feasibility grant, the foundations for detection, sample handling, and the needed algorithms and models were developed. Successive efforts will be made in transferring the methodology to fruit surfaces and to other complex food matrices which can be accomplished with creative sampling methods and experimentation. Even a marginal success in this direction will result in a very significant breakthrough because FTIR and Raman methods, in spite of their limitations are still one of most rapid and nondestructive methods available. Continued interest and efforts in improving the components as well as the refinement of the procedures is bound to result in a significant breakthrough in sensor technology for food safety and biosecurity.
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