Academic literature on the topic 'Crystalline fraction'

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Journal articles on the topic "Crystalline fraction"

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Schmidt, K. J., Y. Lin, M. Beaudoin, G. Xia, S. K. O’Leary, G. Yue, and B. Yan. "The mean crystallite size within a hydrogenated nanocrystalline silicon based photovoltaic solar cell and its role in determining the corresponding crystalline volume fraction." Canadian Journal of Physics 92, no. 7/8 (July 2014): 857–61. http://dx.doi.org/10.1139/cjp-2013-0526.

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We examine the dependence of the crystalline volume fraction on the mean crystallite size for hydrogenated nanocrystalline silicon based photovoltaic solar cells; this work builds upon an earlier study by Schmidt et al. (Mater. Res. Soc. Symp. Proc. 1536 (2013)). For each photovoltaic solar cell considered, the X-ray diffraction and Raman spectra are measured. Through the application of Scherrer’s equation, the X-ray diffraction results are used to determine the corresponding mean crystallite sizes. Through peak decomposition, the Raman results are used to estimate the corresponding crystalline volume fraction. Plotting the crystalline volume fraction as a function of the mean crystallite size, it is found that larger mean crystallite sizes tend to favor reduced crystalline volume fractions. The ability to randomly pack smaller crystallites with a greater packing fraction than their larger counterparts was suggested as a possible explanation for this observation.
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Schmidt, K. J., Y. Lin, M. Beaudoin, G. Xia, S. K. O'Leary, G. Yue, and B. Yan. "The dependence of the crystalline volume fraction on the crystallite size for hydrogenated nanocrystalline silicon based solar cells." MRS Proceedings 1536 (2013): 113–18. http://dx.doi.org/10.1557/opl.2013.599.

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ABSTRACTWe have performed an analysis on three hydrogenated nanocrystalline silicon (nc-Si:H) based solar cells. In order to determine the impact that impurities play in shaping the material properties, the XRD and Raman spectra corresponding to all three samples were measured. The XRD results, which displayed a number of crystalline silicon-based peaks, were used in order to approximate the mean crystallite sizes through Scherrer's equation. Through a peak decomposition process, the Raman results were used to estimate the corresponding crystalline volume fraction. It was noted that small crystallite sizes appear to favor larger crystalline volume fractions. This dependence seems to be related to the oxygen impurity concentration level within the intrinsic nc-Si:H layers.
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Li, J., A. W. Rate, and R. J. Gilkes. "Fractionation of trace elements in some non-agricultural Australian soils." Soil Research 41, no. 7 (2003): 1389. http://dx.doi.org/10.1071/sr02146.

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The fractionation of Ag, Ba, Co, Cr, Cu, Ni, Pb, V, and Zn in highly weathered soils was investigated using 5 operationally defined fractions: exchangeable, organic, amorphous Fe oxides, crystalline Fe oxides, and residual fraction. Crystalline Fe oxide and residual phases were the dominant hosts of Ag in the original soils, but for soils to which soluble Ag was added, much Ag was in the crystalline Fe oxide fractions and only a relatively small proportion of Ag was in the residual fraction. Crystalline Fe oxides and the residual fraction were also the major hosts to Co, Cr, Cu, Ni, Pb, V, and Zn.
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Wang, Fei Peng, Zheng Yong Huang, and Jian Li. "Stretching Induced Crystalline-Phase Transition in Energy-Conversion Poly(Vinylidene Fluoride) (PVDF) Films." Advanced Materials Research 1070-1072 (December 2014): 589–93. http://dx.doi.org/10.4028/www.scientific.net/amr.1070-1072.589.

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Commercial poly (vinylidene fluoride) (PVDF) films are uniaxially stretched with varying rates at 110 °C in order to endow PVDF piezo-and pyroelectric by crystalline-phase transition from α to β during the stretching. The crystalline phases are determined by infrared spectroscopy. The β-phase content and its fraction in films increase as a result of stretching with high rates. In addition, higher stretching rates yield a slight increase of γ phase. The crystallite size is evaluated by means of X-ray diffraction. It is found that the β-phase crystallites become smaller with fast stretching, whereas the α-phase crystallites are cracked and disappear at high-speed stretching of 2.5 /min.
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Agbo, Solomon, Pavol Sutta, Pavel Calta, Rana Biswas, and Bicai Pan. "Crystallized silicon nanostructures — experimental characterization and atomistic simulations." Canadian Journal of Physics 92, no. 7/8 (July 2014): 783–88. http://dx.doi.org/10.1139/cjp-2013-0442.

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We have synthesized silicon nanocrystalline structures from thermal annealing of thin film amorphous silicon-based multilayers. The annealing procedure that was carried out in vacuum at temperatures up to 1100 °C is integrated in a X-ray diffraction (XRD) setup for real-time monitoring of the formation phases of the nanostructures. The microstructure of the crystallized films is investigated through experimental measurements combined with atomistic simulations of realistic nanocrystalline silicon (nc-Si) models. The multilayers consisting of uniformly alternating thicknesses of hydrogenated amorphous silicon and silicon oxide (SiO2) were deposited by plasma enhanced chemical vapor deposition on crystalline silicon and Corning glass substrates. The crystallized structure consisting of nc-Si structures embedded in an amorphous matrix were further characterized through XRD, Raman spectroscopy, and Fourier transform infrared measurements. We are able to show the different stages of nanostructure formation and how the sizes and the crystallized mass fraction can be controlled in our experimental synthesis. The crystallized silicon structures with large crystalline filling fractions exceeding 50% have been simulated with a robust classical molecular dynamics technique. The crystalline filling fractions and structural order of nc-Si obtained from this simulation are compared with our Raman and XRD measurements.
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Anwer, Afzana, S. Eilidh Bedford, Richard J. Spontak, and Alan H. Windle. "Electron microscopy of crystalline structure in thermotropic random copolymers." Proceedings, annual meeting, Electron Microscopy Society of America 49 (August 1991): 1054–55. http://dx.doi.org/10.1017/s0424820100089585.

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Random copolyesters composed of wholly aromatic monomers such as p-oxybenzoate (B) and 2,6-oxynaphthoate (N) are known to exhibit liquid crystalline characteristics at elevated temperatures and over a broad composition range. Previous studies employing techniques such as X-ray diffractometry (XRD) and differential scanning calorimetry (DSC) have conclusively proven that these thermotropic copolymers can possess a significant crystalline fraction, depending on molecular characteristics and processing history, despite the fact that the copolymer chains possess random intramolecular sequencing. Consequently, the nature of the crystalline structure that develops when these materials are processed in their mesophases and subsequently annealed has recently received considerable attention. A model that has been consistent with all experimental observations involves the Non-Periodic Layer (NPL) crystallite, which occurs when identical monomer sequences enter into register between adjacent chains. The objective of this work is to employ electron microscopy to identify and characterize these crystallites.
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Gatos, Konstantinos G., Chrysa Minogianni, and Costas Galiotis. "Quantifying Crystalline Fraction within Polymer Spherulites." Macromolecules 40, no. 4 (February 2007): 786–89. http://dx.doi.org/10.1021/ma0623284.

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Tsuchikawa, T., H. Kaneda, S. Oyabu, T. Kokusho, H. Kobayashi, M. Yamagishi, and Y. Toba. "A systematic study of silicate absorption features in heavily obscured AGNs observed by Spitzer/IRS." Astronomy & Astrophysics 651 (July 2021): A117. http://dx.doi.org/10.1051/0004-6361/202140483.

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Context. Heavily obscured active galactic nuclei (AGNs) are known to show deep silicate absorption features in the mid-infrared (mid-IR) wavelength range of 10–20 μm. The detailed profiles of the features reflect the properties of silicate dust, which are likely to include information on AGN activities obscured by large amounts of dust. Aims. We reveal AGN activities obscured by large amounts of dust through the silicate dust properties obtained from the mid-IR spectral bands. Methods. We selected 115 mid-IR spectra of heavily obscured AGNs observed by Spitzer/IRS and systematically analyzed the composition of silicate dust by spectral fitting using the 10 μm amorphous and 23 μm crystalline bands. Results. We find that the main component of the silicate dust obscuring AGNs is amorphous olivine, the median mass column density of which is one order of magnitude higher than those of the minor components of amorphous pyroxene and crystalline forsterite. The median mass fraction of the amorphous pyroxene, ∼2%, is significantly lower than that of the diffuse interstellar medium (ISM) dust in our Galaxy, while the median mass fraction of the crystalline forsterite, ∼6%, is higher than that of the diffuse ISM dust. We also find that the mass fractions of the amorphous pyroxene and the crystalline forsterite positively correlate with each other. Conclusions. The low mass fraction of the amorphous pyroxene suggests that the obscuring silicate dust is newly formed, originating from starburst activities. The relatively high mass fraction of crystalline forsterite implies that the silicate dust is processed in the high temperature environment close to the nucleus and transported to outer cooler regions by molecular outflows. The positive correlation between the mass fractions can be naturally explained considering that amorphous pyroxene is transformed from crystalline forsterite by ion bombardments. We also find that spectra with high ratios of the H2O ice absorption to silicate mass column density tend to indicate low mass fractions of amorphous pyroxene and crystalline forsterite, which is consistent with the scenario of the thermal dust processing close to the nucleus.
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Baser, T. A., M. Baricco, S. Enzo, G. Vaughan, and A. R. Yavari. "Analysis of crystallization behavior of Fe48Cr15Mo14Y2C15B6 bulk metallic glass by synchrotron radiation." Journal of Materials Research 23, no. 8 (August 2008): 2166–73. http://dx.doi.org/10.1557/jmr.2008.0264.

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The amorphous-to-crystalline transformation behavior of Fe48Cr15Mo14Y2C15B6 bulk metallic glasses was first investigated by high-temperature differential scanning calorimetry. Three events were detected with onset temperatures at 922, 975, and 1036 K, respectively. In situ synchrotron radiation x-ray diffraction patterns were collected during continuous heating and analyzed with the Rietveld approach. To describe simultaneously the amorphous fraction and crystallization products as a function of temperature, a paracrystalline structure-factor model was developed. It was included for quantitative evaluation of the amorphous phase, together with the structure factor of Cr23C6- and Fe3Mo3C-type phases observed during crystallization. Volume fractions of phases as well as lattice parameters, average lattice disorder, and crystallite size of the crystallized phases have been followed as a function of temperature. In this way, the structure evolution and thermal events have been closely inspected and accounted for by a crystallization mechanism.
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MacDonald, Malcolm J., Donna L. Hartley, and Marilyn K. Speedie. "Location of cellulolytic enzyme activity in the marine fungus Trichocladium achrasporum." Canadian Journal of Microbiology 31, no. 2 (February 1, 1985): 145–48. http://dx.doi.org/10.1139/m85-028.

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Cellulase activity in Trichocladium achrasporum was demonstrated by its ability to produce cell-associated and extracellular cellulolytic enzymes when grown on a crystalline cellulose substrate. In addition, azure dye was solubilized from dyed crystalline cellulose, appearing in the growth medium during the phase of cell lysis. Exoglucanase activity was highest in the culture filtrate, with slight activity in the cell fractions, while endoglucanase was associated only with the mycelium. No desorbable exoglucanase nor endoglucanase activity could be released by sonication of residual cellulose particles removed from actively growing cultures. β-Glucosidase activity was located only in the cell-associated fractions during active growth. All enzymes had optimal activity at 50 °C; in the particulate fraction β-glucosidase exhibited a second optimum at 30 °C. In the filtrate, soluble intracellular and particulate fractions optimal exoglucanase activity occurred at pH 6.4, 7.0, and 5.8, respectively. Endoglucanase activity was optimal at pH 5.8 in the soluble cell fraction, and at pH 5.4 in the particulate fraction.
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Dissertations / Theses on the topic "Crystalline fraction"

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Bouillonnec, Jonathan. "Elaboration et étude des propriétés mécaniques et thermiques de matériaux constitués de nanotubes de carbone verticalement alignés." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30228/document.

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Les tapis de nanotubes de carbone verticalement alignés sont des candidats potentiels pour des applications telles que les interconnexions ou les matériaux d'interface thermique. Ce travail de recherche porte sur la synthèse de tapis de nanotubes de carbone alignés selon le procédé de dépôt chimique en phase vapeur (CVD) d'aérosols liquides, sur l'élaboration de nanocomposites constitués de différentes nuances de matrices époxy infiltrées au sein de ces tapis, ainsi que sur l'étude des propriétés mécaniques et thermiques longitudinales et transverses des tapis secs eux-mêmes et des nanocomposites 1D formés. Les conditions de synthèse permettent notamment de faire varier les caractéristiques des tapis telles que leur épaisseur, leur masse volumique, le diamètre externe moyen des nanotubes de carbone (NTC), l'espace intertube et la teneur volumique en NTC, alors que leur structure cristalline peut être modifiée par le biais d'un traitement thermique à haute température. L'objectif principal de ce travail consiste à démontrer et quantifier l'effet de certaines caractéristiques des tapis de nanotubes de carbone sur les propriétés mécaniques et thermiques des différents types de tapis et matériaux composites obtenus. Les deux méthodes d'imprégnation mises en oeuvre, voie liquide et infusion, conduisent à des tapis de NTC alignés denses avec un alignement des NTC conservé et une répartition homogène des NTC au sein du système époxy. La fraction volumique en NTC s'avère être le paramètre-clé permettant d'exacerber, dans la direction longitudinale aux NTC, les propriétés mécaniques et thermiques des nanocomposites. Par ailleurs, les tapis de NTC et les nanocomposites voient leurs propriétés de conduction thermique longitudinale nettement exacerbées lorsque les NTC présentent une amélioration de leur structure cristalline. L'augmentation significative des performances apportées par les tapis de NTC verticalement alignés au sein de ces matériaux nanocomposites anisotropes par rapport aux matrices organiques non chargées est prometteuse et ouvre des pistes de réflexion visant à répondre aux nouvelles exigences de multifonctionnalité des secteurs de l'aéronautique et de l'aérospatial
Vertically aligned carbon nanotube carpets are potential candidates for applications such as interconnections or thermal interface materials (TIMs). This research work deals with the synthesis of aligned carbon nanotube carpets from the aerosol assisted chemical vapour deposition (CVD) technique, with the elaboration of nanocomposites made of different grades of epoxy matrix infiltrated within these carpets, as well as the study of both longitudinal and transverse mechanical and thermal properties of dry carpets themselves and 1D-nanocomposites separately. The synthesis conditions notably enable to vary characteristics of the differents carpets such as their thickness, their density, the mean external diameter of the carbon nanotubes (CNT), the intertube space and the CNT volume fraction, whereas their crystalline structure can be modified with a high temperature thermal treatment. The main goal of this work is to prove and quantify the effect of some of the characteristics of the carbon nanotubes carpets on both mechanical and thermal properties of the different kinds of CNT carpets and resulting composite materials. The two impregnation methods used, liquid way and infusion, lead to dense CNT carpets with a preserved alignment of the CNT and an homogeneous distribution of these latest within the epoxy system. The CNT volume content is evidenced as the key-parameter exacerbating the mechanical and thermal properties mainly in the longitudinal direction compared with the alignment axis of the CNTs. Moreover the mechanical and thermal conduction properties of the CNT carpets and the 1D-nanocomposites are clearly increased when the crystalline structure of the CNT is improved. The significant increasing of the properties brought by the vertically aligned CNT within these anisotropic 1D-nanocomposites compared with the only organic matrixes is promising and opens new pathways aiming to meet the latest specifications related to multifunctionnality in fields such as aeronautics and aerospace
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Simhadri, Dileep. "Determination of Phase Fraction, Lattice Parameters and Crystallite Size in Mechanically Alloyed Fe-Ni Powders." ScholarWorks@UNO, 2003. http://scholarworks.uno.edu/td/56.

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This is the first systematic report on the synthesis of mechanically alloyed Fe-Ni powders ball milled at liquid nitrogen temperature. Pure Fe-Ni samples were ball milled in a SPEX 8000 shaker mill at liquid nitrogen temperature. X-ray diffractometry was used to determine the phase fractions of the bcc and fcc phases in the alloys and to determine the lattice parameters and crystallite size. The main objective of this project is to study how the milling at low temperatures affects the region of two phase co-existence, phase structure and crystallite size. It was found that the composition ranges of the bcc and fcc single phase regions were extended well beyond the equilibrium ranges. The results obtained for the samples ball milled at liquid nitrogen temperature were compared to the previous samples ball milled at room temperature.
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Červený, Ľuboš. "Kinetika neizotermické krystalizace polylaktidu s přídavkem vybraných činidel." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-444212.

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The aim of submitted diploma thesis is the study of non-isothermal crystallization kinetics of polylactide (PLA) with selected agents (1 %) and observation of the emerging crystalline structure under polarizing optical microscope. The agents were talc, a mixture of organic salts with the addition of amorphous SiO2 (HPN 68L) and zinc stearate (HPN 20E) and LAK-301 (potassium salt of 5-dimethylsulfoisophtalate), which is a nucleating agent developer for PLA. The PLA matrix served as a reference. Non-isothermal crystallization took place on a differential scanning calorimeter at cooling rates () 0,3; 0,5; 0,7; 1; 1,5; 2 °C/min After non-isothermal crystallization, the crystalline fraction (Xc) od PLA was evaluated from X-ray diffraction analysis, and the supramolecular structure was observed after chemical degradative etching using confocal laser scanning microscope. The crystallization kinetics were evaluated by the methods of Jeziorny and Mo and the activation energy of the crystallization was determined according to the Friedmann method. All prepared materials were amorphous (Xc 40 % for up to 1,5 °C/min). However, for LAK-301, Xc decreased to 30 % already at the = 2 °C/min and it can be assumed that with increasing its nucleation activity will decrease. A spherulitic structure was observed in all samples, but the number and size of spherulites decreased with increasing and the appearance varied according to the type of agent. Both kinetic models proved to be unsuitable for materials with low Xc and the highest because the rate of crystallization did not change. With the Jeziorny method, it was possible to evaluate the kinetics only for the relative crystallinity Xt = 29–50 % and with the Mo method it was not possible to evaluate the data for the highest for PLA matrix and sample with HPN 68L. The samples with LAK-301 and HPN 68L showed the lowest activation energy.
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Yao, Fang-Hong, and 姚芳弘. "Control of Crystalline Fraction of Hydrogenated Microcrystalline Silicon Films in Catalytic Chemical Vapor deposition." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/41106159717486230080.

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碩士
國立交通大學
顯示科技研究所
98
The crystalline fraction is an important issue for the hydrogenated microcrystalline silicon (μc-Si:H) thin film solar cell. To keep crystalline fraction by catalytic chemical vapor deposition (Cat-CVD), we investigated the controlling of H2 dilution ratio in this study. In addition, the information on microcrystalline silicon bonding configuration was obtained by Fourier Transform Infrared Spectroscopy (FTIR) and we have used photo conductivity and dark conductivity to analyze hydrogenated microcrystalline silicon (μc-Si:H) thin film. In addition, we have proceeded experiment about substrate temperature to deposit hydrogenated microcrystalline silicon thin film. And then we have discussed substrate effect probably influence our experiment, so we will use glass substrate、amorphous silicon / glass substrate and microcrystalline silicon / glass substrate to discuss in this study.
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Simhadri, Dileep Kumar. "Determination of phase fraction, lattice parameters and crystallite size in mechanically alloyed Fe-Ni powders." 2003. http://louisdl.louislibraries.org/u?/NOD,73.

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Thesis (M.S.)--University of New Orleans, 2003.
Title from electronic submission form. "A thesis ... in partial fulfillment of the requirements for the degree of Master of Science in Mechanical Engineering"--Thesis t.p. Vita. Includes bibliographical references.
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Book chapters on the topic "Crystalline fraction"

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Riello, P. "Quantitative Analysis of Amorphous Fraction in the Study of the Microstructure of Semi-crystalline Materials." In Diffraction Analysis of the Microstructure of Materials, 167–84. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-662-06723-9_7.

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Owaki, Shigehiro, Toichi Okada, Sumio Nakahara, and Kiyoshi Sugihara. "Fracto-Emission from Crystalline and Non-Crystalline Materials at Cryogenic Temperatures." In Materials, 397–404. Boston, MA: Springer US, 1992. http://dx.doi.org/10.1007/978-1-4757-9050-4_50.

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Hug, W., and P. R. Sahm. "Effect of the Cooling Rate on the AS-Cast Fraction Crystallized." In Science and Technology of the Undercooled Melt, 240. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4456-5_16.

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Aspnes, D. E., C. E. Bouldin, and E. A. Stern. "Structural and Microstructural Determinations of Crystalline and Amorphous Fractions of Microcrystalline Ge: A Comparison." In Proceedings of the 17th International Conference on the Physics of Semiconductors, 841–44. New York, NY: Springer New York, 1985. http://dx.doi.org/10.1007/978-1-4615-7682-2_187.

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Dosière, M., C. Fougnies, M. H. J. Koch, and J. Roovers. "Lamellar Morphology of Narrow PEEK Fractions Crystallized from the Glassy State and from the Melt." In ACS Symposium Series, 166–86. Washington, DC: American Chemical Society, 1999. http://dx.doi.org/10.1021/bk-2000-0739.ch011.

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Chen, Er-Qiang, Song-Wook Lee, Anqiu Zhang, Bon-Suk Moon, Ian Mann, Frank W. Harris, Stephen Z. D. Cheng, Benjamin S. Hsiao, Fengji Yeh, and Ernst D. von Meerwall. "Isothermal Thickening and Thinning Processes in Low Molecular Weight Poly(ethylene oxide) Fractions Crystallized from the Melt." In ACS Symposium Series, 118–39. Washington, DC: American Chemical Society, 1999. http://dx.doi.org/10.1021/bk-2000-0739.ch008.

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Mauge, F., J. C. Courcelle, Ph Engelhard, P. Gallezot, J. Grosmangin, M. Primet, and B. Trusson. "Hydrothermal Ageing of Cracking Catalysts. I-Evaluation of the Crystalline Fraction of Zeolites." In Studies in Surface Science and Catalysis, 401–9. Elsevier, 1985. http://dx.doi.org/10.1016/s0167-2991(08)65307-0.

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Chong, Parkson Lee-Gau. "Membrane-Free Volume Variation with Bulky Lipid Concentration by Regular Distribution: A Functionally Important Membrane Property Explored by Pressure Studies of Phosphatidylcholine Bilayers." In High Pressure Effects in Molecular Biophysics and Enzymology. Oxford University Press, 1996. http://dx.doi.org/10.1093/oso/9780195097221.003.0022.

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We have used the dips in the ratio of excimer to monomer fluorescence intensity (E/M) as the index of lipid regular distribution to examine the effect of pressure on lipid lateral organization in the liquid-crystalline state of dimyristoylphosphatidylcholine (DMPC)/1-palmitoyl-2-(10-pyrenyl)decanoyl)-sn-glyceroI-3-phosphatidylcholine (Pyr-PC) bilayers. In the pressure range of 0.001-0.7 kbar at 30 °C, E/M dips remain discernible, suggesting that lipid regular distribution appears favorably in the liquid-crystalline state. In the same pressure range, E/M decreases steadily with increasing pressure at noncritical mole fractions; in contrast, E/M changes little with pressure at critical mole fractions. This result reveals an important physical principle underlying lipid regular distribution—that is, that membrane free volume reaches a local minimum at critical mole fractions of bulky lipids (for example, cholesterol and Pyr-PC). Using the activity of phospholipase A2 and the membrane fluidity inferred from diphenylhexatriene fluorescence polarization, we demonstrate that regular distribution of bulky lipids has a regulatory role in membrane properties or functions. Our data show that the activity of snake venom phospholipase A2 can be significantly modulated by minute changes (for example, 0.5 mol%) in the concentration of bulky lipids on either side of a critical mole fraction as a result of membrane free volume variation. The approach employed in this study illustrates the usefulness of high-pressure fluorescence methodology for obtaining new information about membranes at ambient conditions. High-pressure fluorescence spectroscopy has emerged as a powerful tool in biophysical research during the past 15 years (Paladini & Weber, 1981; Weber, 1992). Previous fluorescence studies of membranes at high pressure were focused on dynamic aspects, particularly on membrane fluidity. These dynamic studies have included probe rotations in lipid membranes (Chong & Weber, 1983; Chong et al., 1983; Mateo et al, 1993 and references cited therein), probe lateral diffusion (Flamm et al, 1982; Muller & Galla, 1983, 1987; Turley & Offen, 1985, 1986; Eisinger & Scarlata, 1987; Macdonald et al., 1988; Kao et al., 1992), spontaneous intermembrane transfer (Mantulin et al., 1984), and the relationship of membrane dynamics to the activity of membrane-bound proteins (Chong et al, 1985; Verjovski-Almeida et al, 1986; Jona & Martonosi, 1991).
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Juo, Anthony S. R., and Kathrin Franzluebbers. "Properties and Management of Oxidic Soils." In Tropical Soils. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195115987.003.0015.

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Oxidic soils are deeply weathered, fine-textured, oxide-rich soils in the tropics. These soils are the second most abundant soils in the tropics. Geographically, oxidic soils are found in Latin America (Brazil, Central America), East and Central Africa (Kenya, Congo, and Cameroon), the Caribbean Basin, and the Pacific Islands. In southeastern Asia, oxidic soils are found in isolated areas of Indonesia, the Philippines, and northern Australia, usually on the volcanic and limestone-dominated geomorphic surfaces. Oxidic soils are oxide-rich, low bulk density Oxisols, Alfisols, and Ultisols according to the Soil Taxonomy classification. In other soil classification schemes, most oxidic soils are classified under Sols Ferallitiques according to the French system, and Ferralsols and Nitosols under the FAO/UNESCO system. Oxidic soils are differentiated into high-base-status and low-base-status soils on the basis of the 70% base saturation limit calculated from effective CEC. The high-base-status oxidic soils generally are enriched with Ca-saturated organic matter in the surface layer and are among the more productive upland soils in the tropics. The low-base-status oxidic soils are acidic, have a low effective CEC, and the degree of exchangeable Al saturation often exceeds 60% in the subsoil horizons. Because of their excellent soil physical properties, oxidic soils are more resistant to soil erosion and therefore better suited to large-scale mechanized agriculture than kaolinitic soils. Although the dominant clay mineral is kaolinite, the presence of moderate amounts of crystalline and amorphous Fe and Al oxides and hydrous oxides (around 5% Fe2O3 or higher) with a high specific surface area (100 m2/g or larger) gives rise to many unique chemical and physical properties, such as a variable surface charge, the formation of microaggregates, low bulk density (0.8-1.2 Mg/ m3), stable soil structure, and high permeability. Most oxidic soils are red or dark red due to the presence of clay-size hematite (Fe2O3) in the soil. The yellowish oxidic soils contain primarily goethite (FeOOH) in the clay fraction and occur in the wetter geomorphic positions of a deeply weathered landscape. Extensive areas of clayey, yellowish oxidic soils are found in the Amazon Basin. Gibbsite (A1OOH) is the major crystalline Al oxide.
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Taitel-Goldman, Nurit, and Vladimir Ezersky. "Nano-Sized Minerals from Lower Cretaceous Sandstones in Israel Observed by Transmission Electron Microscopy (TEM)." In Nanocrystals [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96948.

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Fine fraction in quartz arenite sandstones from Lower Cretaceous Hatira formation in Israel was observed by Transmission electron microscope (TEM). Samples were collected from Hatira and Ramon craters located in southern part of Israel and from Manara cliff from the northern part of Israel. The additional phases cause yellow, red, dark red and dark violet colors of the layered sandstones. The motivation was to identify the minerals of the fine factions that cause the variations in the colors. The minerals observed were clay minerals, mainly kaolinite (Al4Si4O20(OH)8), some illite (K0.65Al2.0[Al0.65Si3.35O10](OH)2) and smectite. Iron oxides were goethite (FeOOH) and hematite (Fe2O3), Titanium-iron oxides observed was ilmenite (FeTiO3), and Titanium-oxides were rutile (TiO2), and anatase (TiO2). Sulphates observed were jarosite (KFe3(SO4)2(OH)6) and alunite (KAl3(SO4)2(OH)6). Some of the hematite was formed by recrystallization of goethite. Ilmenite disintegrated into small iron oxides mainly hematite. Euhedral to sub-hedral rutile (TiO2) and anatase (TiO2) were preserved in clay-minerals. Crystals of alunite and jarosite were observed in sandstones in both craters. They probably crystallized due to some transgression of the Thetis Sea.
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Conference papers on the topic "Crystalline fraction"

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Lanterne, Adeline, Guilherme Gaspar, Bjørn Haave, Moez Jomâa, Rune Søndenå, Alexander Hupfer, Yu Hu, and Marisa Di Sabatino. "Impact of thermal history on defects formation in the last solid fraction of Cz silicon ingots." In SILICONPV 2018, THE 8TH INTERNATIONAL CONFERENCE ON CRYSTALLINE SILICON PHOTOVOLTAICS. Author(s), 2018. http://dx.doi.org/10.1063/1.5049331.

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Tita, D. L., S. G. Antonio, and C. O. Paiva-Santos. "CRYSTALLOGRAPHIC ANALYSIS OF FUROSEMIDE: IDENTIFICATION AND QUANTIFICATION OF CRYSTALLINE FRACTION ON ACTIVE INGREDIENT." In International Symposium on Crystallography. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/phypro-sic100-069.

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Ning-Yi Yuan, Shu-Bo Wang, Xiu-Qin Wang, Jian-Ning Ding, Feng Ye, Jia-Li Zhang, and Hong-Min Chen. "Simulation research of biphasic silicon thin film solar cell of different crystalline volume fraction." In 2010 International Conference on Optics, Photonics and Energy Engineering (OPEE 2010). IEEE, 2010. http://dx.doi.org/10.1109/opee.2010.5508102.

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4

Chen, Qingdong, and Junping Wang. "Study on Crystalline Volume Fraction and Activation Energy for Silicon Thin Film Prepared by VHF-PECVD." In 2017 6th International Conference on Energy and Environmental Protection (ICEEP 2017). Paris, France: Atlantis Press, 2017. http://dx.doi.org/10.2991/iceep-17.2017.128.

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Liu, F. "The Crystalline Volume Fraction Dependence of Anisotropic Electrical Transport in nc-Si Thin Films—Theoretical and Experimental Studies." In PHYSICS OF SEMICONDUCTORS: 27th International Conference on the Physics of Semiconductors - ICPS-27. AIP, 2005. http://dx.doi.org/10.1063/1.1994368.

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Alvarez-Macias, C., E. Barrera Calva, B. M. Monroy, A. Dutt, and G. Santana. "The role of crystalline fraction on the photoconductive response in polymorphous silicon materials for thin films solar cells." In 2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC). IEEE, 2016. http://dx.doi.org/10.1109/pvsc.2016.7749666.

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7

Saavedra Flores, Erick I., Senthil Murugan, Michael I. Friswell, and Eduardo A. de Souza Neto. "Fully Coupled Three-Scale Finite Element Model for the Mechanical Response of a New Bio-Inspired Composite." In ASME 2011 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2011. http://dx.doi.org/10.1115/smasis2011-4946.

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This paper proposes a fully coupled three-scale finite element model for the mechanical description of an alumina/magnesium alloy/epoxy composite inspired in the mechanics and architecture of wood cellulose fibres. The constitutive response of the composite (the large scale continuum) is described by means of a representative volume element (RVE, corresponding to the intermediate scale) in which the fibre is represented as a periodic alternation of alumina and magnesium alloy fractions. Furthermore, at a lower scale the overall constitutive behavior of the alumina/magnesium alloy fibre is modelled as a single material defined by a large number of RVEs (the smallest material scale) at the Gauss point (intermediate) level. Numerical material tests show that the choice of the volume fraction of alumina based on those volume fractions of crystalline cellulose found in wood cells results in a maximisation of toughness in the present bio-inspired composite.
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Katika, Kamal M., and Laurent Pilon. "The Effect of Nanoparticles on the Thermal Conductivity of Crystalline Thin Films at Low Temperatures." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-43466.

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This study is concerned with the prediction of the effective thermal conductivity of nanocomposite thin films consisting of nanoparticles randomly distributed in a solid matrix. Crystalline sodium chloride with embedded monodisperse silver nanoparticles is investigated as a case study for thin films where phonons are the main heat carriers. To the best of our knowledge, the equation for phonon radiative transfer is solved for the first time with an exact scattering transport cross-section of the nanoparticles as a function of frequency which was obtained from the literature. The one-dimensional equation for phonon radiative transfer based on the isotropic scaling approximation is solved on a spectral basis using the discrete ordinates method to predict the temperature profile and the heat flux across the nanocomposite thin films. The thermal conductivity is retrieved at temperatures where the effects of Umklapp and Normal processes can be neglected and scattering by the particles on phonon transport dominates. The method of solution and closure laws were validated with experimental data of thermal conductivity for bulk samples at 2.53, 5.94, and 10.56 K. The effects of the film thickness (1 μm to 2.5 cm), nanoparticle diameter (5 nm to 100 nm) and volume fraction (0.0001 to 0.2) on the thermal conductivity of the nanocomposite thin film are investigated. The results indicate that the thermal conductivity decreases with decreasing particle radius as well as with increasing particle concentration. Finally, a dimensionless analysis revealed a power law relationship between the dimensionless thermal conductivity and a dimensionless length of the order of the acoustic thickness of the medium. These results can be used to design nanocomposite thin films for various low temperature thermal applications by choosing optimal nanoparticle radius and volume fraction, and film thickness.
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Tung, F. C., M. C. Huang, T. S. Chin, Nguyen Chi Lang, P. S. Wu, Edward Yi-Chang, and J. H. Huang. "Control of crystalline volume fraction of μC-Si thin film using 40.68 MHz PECVD system for solar cell application." In 2010 35th IEEE Photovoltaic Specialists Conference (PVSC). IEEE, 2010. http://dx.doi.org/10.1109/pvsc.2010.5616051.

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Prasher, Ravi. "Modification of Planck Black Body Emissive Power and Intensity in Particulate Media Due to Multiple and Dependent Scattering." In ASME 2005 Summer Heat Transfer Conference collocated with the ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems. ASMEDC, 2005. http://dx.doi.org/10.1115/ht2005-72047.

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Dispersion relation for electromagnetic wave is obtained in particulate media using effective field approximation (EFA) and quasi crystalline approximation (QCA). Due to multiple and dependent scattering the density of states, phase velocity and group velocity of photons are modified. Modification of these parameters modifies the Planck black body equilibrium radiation intensity. This modification affects the temperature and the heat flux predictions in multiple and dependent scattering particulate media. Results show that EFA can accurately capture the dependence of density of states, phase velocity and the group velocity on volume fraction of scatterers whereas QCA can capture the dependence of effective attenuation as well as density of states, phase velocity and the group velocity. Comparisons of the temperature, heat flux, and effective attenuation are made between EFA, QCA and work done by C.L Tien and coworkers. Results show that heat flux and temperature predictions made by models in the literature for multiple and dependent scattering are not correct as these models do not take the modification of the equilibrium intensity into account. Finally we introduce a new model called Dependent Effective Field Approximation (DEFA) which accurately captures the effect of volume fraction on the equilibrium intensity, and effective attenuation. All relations derived in the paper are for spherical particles.
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