Journal articles: 'Crystalline properties'

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Savkina, R. K. "Properties of the crystalline silicon strained via cavitation impact." Semiconductor Physics Quantum Electronics and Optoelectronics 16, no. 1 (February 28, 2013): 43–47. http://dx.doi.org/10.15407/spqeo16.01.043.

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Nachbar, Mario, Denis Duft, and Thomas Leisner. "The vapor pressure over nano-crystalline ice." Atmospheric Chemistry and Physics 18, no. 5 (March 8, 2018): 3419–31. http://dx.doi.org/10.5194/acp-18-3419-2018.

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Abstract. The crystallization of amorphous solid water (ASW) is known to form nano-crystalline ice. The influence of the nanoscale crystallite size on physical properties like the vapor pressure is relevant for processes in which the crystallization of amorphous ices occurs, e.g., in interstellar ices or cold ice cloud formation in planetary atmospheres, but up to now is not well understood. Here, we present laboratory measurements on the saturation vapor pressure over ice crystallized from ASW between 135 and 190 K. Below 160 K, where the crystallization of ASW is known to form nano-crystalline ice, we obtain a saturation vapor pressure that is 100 to 200 % higher compared to stable hexagonal ice. This elevated vapor pressure is in striking contrast to the vapor pressure of stacking disordered ice which is expected to be the prevailing ice polymorph at these temperatures with a vapor pressure at most 18 % higher than that of hexagonal ice. This apparent discrepancy can be reconciled by assuming that nanoscale crystallites form in the crystallization process of ASW. The high curvature of the nano-crystallites results in a vapor pressure increase that can be described by the Kelvin equation. Our measurements are consistent with the assumption that ASW is the first solid form of ice deposited from the vapor phase at temperatures up to 160 K. Nano-crystalline ice with a mean diameter between 7 and 19 nm forms thereafter by crystallization within the ASW matrix. The estimated crystal sizes are in agreement with reported crystal size measurements and remain stable for hours below 160 K. Thus, this ice polymorph may be regarded as an independent phase for many atmospheric processes below 160 K and we parameterize its vapor pressure using a constant Gibbs free energy difference of (982 ± 182) J mol−1 relative to hexagonal ice.

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Majerová, Melinda, Martin Škrátek, Branislav Hruška, Andrej Dvurečenskij, Peter Švančárek, Anna Prnová, Jozef Kraxner, Els Bruneel, Klaartje De Buysser, and Dušan Galusek. "Structure and magnetic properties of Bi-doped calcium aluminosilicate glass microspheres." Pure and Applied Chemistry 94, no. 2 (January 6, 2022): 197–213. http://dx.doi.org/10.1515/pac-2021-0703.

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Abstract Bi-doped CaO–Al2O3–SiO2 glass microspheres with Ca2Al2SiO7 (gehlenite) composition were prepared by combination of solid-state reaction and flame synthesis. The concentration of Bi was 0.0, 0.5, 1 and 3 mol%. The chemical composition of prepared glass microspheres was determined by X-ray fluorescence (XRF). The structural and magnetic properties of prepared glass microspheres and their polycrystalline analogues were studied by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Raman spectroscopy and SQUID magnetometry. The closer inspection of glass microspheres surface by SEM confirmed smooth surface and revealed no features indicating presence of crystalline phases. All Bi-doped microspheres are X-ray amorphous, however in case of undoped microspheres XRD detected traces of crystalline gehlenite. XRD analysis of samples crystallized at 1273 K for 10 h revealed the presence of gehlenite as the main crystalline phase. The presence of gehlenite in crystallized samples were also confirmed by Raman spectroscopy. All samples (glass microspheres and their crystalline analogues) showed diamagnetic or weak ferromagnetic behavior at room temperature, whereas paramagnetic or weak ferromagnetic behavior was observed at 2 K.

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Wang, Xiao, Zhihua Shen, Jie Li, and Shengli Wu. "Preparation and Properties of Crystalline IGZO Thin Films." Membranes 11, no. 2 (February 14, 2021): 134. http://dx.doi.org/10.3390/membranes11020134.

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IGZO thin films can be used as active layers of thin-film transistors and have been widely studied. However, amorphous indium gallium zinc oxide (IGZO) fabricated at room temperature is vulnerable in subsequent manufacturing processes, such as etching and sputtering; this limits IGZO thin film transistors’ (TFTs) use in commercial products. In this paper, we prepared a c-axis crystallized IGZO thin film by Radio Frequency (RF) sputtering at 180 °C, with a 50% O2 ratio and 110 W power. XRD images show that the crystallized film has an obvious diffraction peak near 31°, and the spacing between the crystal surfaces was calculated to be ≈0.29 nm. The HRTEM map confirmed the above results. The stability of IGZO thin films was investigated by etching them with an acid solution. The crystalline IGZO films exhibited better acid corrosion resistance, and their anticorrosion performance was 74% higher than that of amorphous IGZO (a-IGZO) films, indicating the crystalline IGZO film can provide more stable performance in applications.

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Dhaouadi, Hassouna, Ouassim Ghodbane, Faouzi Hosni, and Fathi Touati. "Mn3O4 Nanoparticles: Synthesis, Characterization, and Dielectric Properties." ISRN Spectroscopy 2012 (February 15, 2012): 1–8. http://dx.doi.org/10.5402/2012/706398.

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Mn3O4 nanoparticles were prepared by a simple chemical route using cetyltetramethylammonium bromide (CTAB) as a template agent. Mn3O4 nanocrystals present an octahedral shape, and their crystallite size varies between 20 and 80 nm. They were characterized by XRD, SEM, DTA/TG, and IR spectroscopy. XRD studies confirm the presence of a highly crystalline Mn3O4 phase. The Rietveld refinement of the X-ray diffraction data confirms that Mn3O4 nanoparticles crystallize in the tetragonal system with space group I41/amd. DTA/TG and XRD measurements demonstrate the phase transition toward a spinel structure between 25 and 700∘C. The electrical conductivity increases between 80 and 300∘C, suggesting a semiconducting behaviour of Mn3O4. Both dielectric dispersion (ε′) and dielectric loss (ε′′) were investigated from 80 and 300∘C in the frequency range of 10 Hz–13 MHz. The dielectric properties showed typical dielectric dispersion based on the Maxwell-Wagner model.

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Mosquera, Edgar Eduardo, Daniela Herrera-Molina, and Jesús Diosa. "Structural and optical properties of TiO2 nanoparticles and their photocatalytic behavior under visible light." INGENIERÍA Y COMPETITIVIDAD 23, no. 2 (May 18, 2021): e21310965. http://dx.doi.org/10.25100/iyc.v23i2.10965.

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TiO2 nanoparticles were successfully synthesized using a facile and scalable sol-gel method and their structural and optical properties studied. XRD ad FTIR was used to identify the phase, crystallite size, and functional groups present in the nanoparticles. The prepared samples crystallize in the anatase structure with highly crystalline order. TEM/EDX shows that the nanoparticles are pure, spherical, and with an average particle size of 15 ± 2 nm. The bandgap energy was 3.59, 3.79, and 3.64 eV, respectively. PL emission is attributed to oxygen vacancies (Vo). The calcination temperature at 450 °C suggests a better photocatalytic performance under visible light compared with other sample's thermal treatments.

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Liang, Yuan-Chang, and Che-Wei Chang. "Preparation of Orthorhombic WO3 Thin Films and Their Crystal Quality-Dependent Dye Photodegradation Ability." Coatings 9, no. 2 (February 2, 2019): 90. http://dx.doi.org/10.3390/coatings9020090.

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Direct current (DC) magnetron sputtering deposited WO3 films with different crystalline qualities were synthesized by postannealing at various temperatures. The in-situ DC sputtering deposited WO3 thin film at 375 °C exhibited an amorphous structure. The as-grown WO3 films were crystallized after annealing at temperatures of 400–600 °C in ambient air. Structural analyses revealed that the crystalline WO3 films have an orthorhombic structure. Moreover, the crystallite size of the WO3 film exhibited an explosive coarsening behavior at an annealing temperature above 600 °C. The density of oxygen vacancy of the WO3 films was substantially lowered through a high temperature annealing procedure. The optical bandgap values of the WO3 films are highly associated with the degree of crystalline quality. The annealing-induced variation of microstructures, crystallinity, and bandgap of the amorphous WO3 thin films explained the various photoactivated properties of the films in this study.

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Ebnalwaled, A. A., and M. Abou Zied. "Microstructure and Mechanical Properties of Nano-Crystalline Al-Mg-Mn System." Journal of Nano Research 9 (February 2010): 61–68. http://dx.doi.org/10.4028/www.scientific.net/jnanor.9.61.

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Nano - crystalline Al-Mg-Mn was synthesized by ball milling technique. Microstructure of these alloys has been studied from X-ray line broadening. The crystallite size of nano - crystalline Al-Mg-Mn system decreases by increasing the Mg content, While the micro-strain, median diameter,, and geometrical standard deviations,  increases by increasing the Mg content. Micro-hardness of our system has been investigated by Vickers hardness test. The hardness increases by increasing the Mg content.

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Sheu, Hwo-Shuenn, Chung-Kai Chang, Yu-Chun Chuang, Wei-Tsung Chuang, Chun-Yu Chen, Sean Blamires, Chen-Pan Liao, and I.-Min Tso. "Nutrient and Wind Effects on Dragline Properties: Perspectives from WAXS & SAXS." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1322. http://dx.doi.org/10.1107/s205327331408677x.

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Spider dragline silk is one of the strongest nature fibers and some of their features are even better than those of the best synthetic fibers. Understanding the mechanisms inducing silk variability may have implications for biomimetics and the synthesis of environmentally responsive materials. Dragline silk contains both elasticity (amorphous) and crystalline regions. Our previous studies had demonstrated that spiders might vary the protein composition and thus physical properties of silks when experiencing food with different nutrient level. In this study we fed Nephila pilipes with high, low and no protein foods and collected their dragline silks for synchrotron Radiation (SR) wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS) examinations. The WAXS data showed a significant difference in crystalline fractions of dragline silks produced by N. pilipes experiencing different food treatments. In addition, the orientation of crystallines also varied considerably among silks produced by spiders in three treatment groups. The SAXS data, obtained with the beam incident along and perpendicular to the fiber axis revealed a mesostructure comprising nano crystallites (beta sheets) stack spirally along the spider fibril axis. Such results indicate that spiders experiencing different nutrient stress level might produce dragline silks of different physical properties due to variations in crystalline density, orientation and the meso-phase structures in nano scale. Furthermore, varying environmental wind strength leads to changes in tensile mechanics of spider dragline silk hence produced. Exposing the spider Cyclosa mulmeinensis to controlled stress from constant airflow, we found correlated changes in (i) amino acid composition, (ii) tensile mechanics and (iii) crystallinity, of the dragline silk; which results suggest that protein variation and/or post secretion crystalline variations are associated with the mechanical properties of the spider silks.

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Safari, Maryam, Itziar Otaegi, Nora Aramburu, Gonzalo Guerrica-Echevarria, Antxon de Ilarduya, Haritz Sardon, and Alejandro Müller. "Synthesis, Structure, Crystallization and Mechanical Properties of Isodimorphic PBS-ran-PCL Copolyesters." Polymers 13, no. 14 (July 9, 2021): 2263. http://dx.doi.org/10.3390/polym13142263.

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Isodimorphic behavior is determined by partial inclusion of comonomer segments within the crystalline structure and arises from the comparatively similar repeating chain units of the parental homopolymers. Isodimorphic random copolymers are able to crystallize irrespective of their composition and exhibit a pseudo-eutectic behavior when their melting point values are plotted as a function of comonomer content. At the pseudo-eutectic point or region, two crystalline phases can coexist. On the right-hand and the left-hand side of the pseudo-eutectic point or region, only one single crystalline phase can form which is very similar to the crystalline structures of the parent homopolymers. This article aims to study the synthesis method, structure, crystallization behavior and mechanical properties of isodimorphic random PBS-ran-PCL copolyesters. Moreover, this study provides a comprehensive analysis of our main recent results on PBS-ran-PCL random copolyesters with three different molecular weights. The results show that the comonomer composition and crystallization conditions are the major factors responsible for the crystalline morphology, crystallization kinetics and mechanical performance of isodimorphic random copolyesters. Our studies demonstrate that in the pseudo-eutectic region, where both crystalline phases can coexist, the crystallization conditions determine the crystalline phase or phases of the copolymer. The relationships between the comonomer composition and mechanical properties are also addressed in this work.

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Ramesh, K., Pumlianmunga, R. Venkatesh, N. Naresh, and E. S. R. Gopal. "Phase Change Properties of Chalcogenide Glasses - Some Interesting Observations." Key Engineering Materials 702 (July 2016): 37–42. http://dx.doi.org/10.4028/www.scientific.net/kem.702.37.

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Chalcogenide glasses switches from a high-resistance (OFF) state to a low-resistance (ON) state at a threshold voltage (Vth) under high electric fields. This electrical switching is of two types: (i) Threshold switching and (i) memory switching. Threshold switching device revert back to the OFF state immediately upon the removal of the applied voltage, whereas a memory device retains the ON state even after the removal of the applied voltage. Due to Joule heating, a filament is formed between the electrodes and the current is confined within this filament and there is an increase in current density. This increases the temperature inside the filament and there is a transition from high resistive amorphous/glass phase to a low resistive crystalline phase in memory switching materials. In the threshold switching glasses electronic processes like space charge, Poole-Frenkel effect, etc., are responsible. The structural transitions are irreversible whereas the electronic processes are reversible and hence the threshold glasses regain their original state (OFF) and memory glasses remain in the ON state.Interestingly, differential scanning calorimetric studies (DSC) show that both the threshold and memory switching glasses exhibit crystallization (structural transition). Accordingly, glasses which crystallize upon heating should exhibit memory switching behaviour. But the switching experiments indicate that among the glasses which undergo structural transition (crystallization) some show threshold switching and some show memory switching. To understand this, Cu-As-Se, Al-As-Te, Ge-As-Se-Te, Al-As-Se-Te glasses were thermally crystallized under vacuum in two ways: (i) by annealing at their respective crystallization temperatures (Tc) and (ii) heated up to their melting temperatures (Tm) and cooled back to room temperature. Interestingly, most of the threshold switching glasses shows amorphous nature or a huge amorphous background with crystalline peaks when cooled from their melting temperatures. The memory switching glasses crystallize in both the cases.We propose that both threshold and memory glasses undergo phase change and the crystalline phases formed from the melt state are responsible for switching to occur. Hence, at the time of switching the sample in between the electrodes undergo phase change by glass → melt → crystal transformation and not by the direct glass → crystal transformation.

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Кравец, В. А., Е. В. Иванова, К. Н. Орехова, Г. А. Гусев, В. В. Васькевич, М. И. Москвичёв, and М. В. Заморянская. "Низкотемпературный синтез стеклокерамики с кристаллитами YNbO-=SUB=-4-=/SUB=- : Eu-=SUP=-3+-=/SUP=-." Оптика и спектроскопия 129, no. 2 (2021): 207. http://dx.doi.org/10.21883/os.2021.02.50559.179-20.

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The main purpose of this work was to carry out a low-temperature synthesis of glass ceramics containing YNbO4:Eu3+ crystallites and to study the structural and luminescent properties of the obtained samples. Within the framework of this work, the inclusions that crystallized under the conditions of low-temperature synthesis in the systems of SiO2-Na2O-K2O-Y2O3-Nb2O5-Eu2O3 (SiNaK) and B2O5-Na2O-Y2O3-Nb2O5-Eu2O3 (BNa) were investigated for the first time. It was shown that YNbO4: Eu3+ crystallized in both considered systems. In the SiNaK system the crystallization of SiO2 also occurred (quartz, crisstabolite, and tridymite) under the selected conditions. The BNa system proved to be the most promising for the synthesis of activated glass-ceramics with YNbO4, since the required crystallites crystallized only in ithis system. The luminescent properties of crystalline inclusions were investigated using the local cathodoluminescence technique. The composition and structure of glass ceramics were studied by electron-probe microanalysis and X-ray diffraction phase analysis.

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Gonzáles, Sergio, P. Pérez, G. Garcés, and P. Adeva. "Effect of RE Elements and Ni Contents on the Microstructure and Mechanical Properties of Rapidly Solidified Mg Ribbons." Materials Science Forum 539-543 (March 2007): 1662–68. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.1662.

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The effect of the concentration of Ni, Y and La-rich mischmetal on the thermal stability, microstructure and mechanical properties of ribbons tested in the temperature range 25-350°C have been evaluated. The low-alloyed materials were crystalline or partially crystalline while high-alloyed materials were amorphous. The amorphous alloys experienced numerous transformations during heating above 170°C. A transition in the amorphous state was observed in all alloys prior to the crystallization stage. The alloy composition determines the sequence of phase transformations during crystallization. In general, the structure of crystallised amorphous, even at high temperatures, is much finer than that of crystalline materials. A MgxREy intermetallic matrix with other intermetallic phases homogeneously distributed was observed in the crystallised ribbons with high RE contents. However, a magnesium matrix embedding other intermetallic phases was the microstructure observed for low-alloyed materials. The amorphous Mg-10Ni-2.5Y2.5-2.5La(MM) showed the higher tensile strength values up to 200 °C The crystalline Mg-2Ni-1Y-1La(MM) ribbon and the partially crystalline Mg-3Ni-1.5Y-1.5La(MM) alloy also exhibited high mechanical resistance levels which were maintained up to 250 °C. MgNi10Y2.5La(MM)2.5 amorphous and MgNi3Y1.5La(MM)1.5 crystalline broken above 500 and 400 MPa, respectively, at 100°C

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González, Julio, Lifang Chen, and Jin An Wang. "Crystalline structure, oxygen defects and textural properties of the CeO₂/SBA-15 nanomaterials." Journal of Physics: Conference Series 2307, no. 1 (September 1, 2022): 012038. http://dx.doi.org/10.1088/1742-6596/2307/1/012038.

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Abstract In this study, a series of CeO2/SBA-15 nanomaterials were synthesized by varying the CeO2 content. These materials were characterized by different techniques to determine their textural, surface chemical and crystalline properties. Crystallite size and oxygen defects were determined by Microanalysis Using X-Ray Diffraction (MAUD) software based on the Rietveld refinement method. The results showed that the crystallite size slightly increased from 5.6 to 8.4 nm and the surface area decreased from 620 to 370 m2/g as CeO2 content increased from 5 to 10, 15 to 20wt%. The oxygen occupancy that was associated with oxygen defects was found in the crystalline structure of CeO2. The defect concentration was between 6.18 and 14.42%, depending on the ceria content and dispersion. This study confirmed that the CeO2/SBA-15 nanomaterials have larger surface area, highly dispersed CeO2 nanoparticles, and a big number of oxygen defects in the crystalline structure, which can be used in different catalytic reactions.

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HARTRIDGE, A., M. GHANASHYAM KRISHNA, and A. K. BHATTACHARYA. "STRUCTURE AND OPTICAL PROPERTIES OF NANOCRYSTALLINE ERBIA DOPED ZIRCONIA THIN FILMS." International Journal of Modern Physics B 14, no. 11 (May 10, 2000): 1239–48. http://dx.doi.org/10.1142/s0217979200000984.

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Thin films of zirconia doped with erbia in the concentration range of 5 to 15% have been prepared on quartz substrates by an inorganic and aqueous sol–gel method. The films were crystalline, continuous and single phase as deposited, with a cubic fluorite structure and crystallite sizes of 8–10 nm as shown by X-ray diffraction. The films were annealed to 600 and 1050°C after deposition and found to be transparent in the region between 400 to 1100 nm, the crystalline structure becoming tetragonal at 1050°C with crystallite sizes of around 30–40 nm. The refractive index increased with increase in annealing temperature. There is a peak in the refractive index at a dopant concentration of 10% where it achieves a value of 1.88 at 700 nm. The optical absorption edge shows a similar peak at the same dopant concentration with a value of 5.65 eV.

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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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PANT, R. P., VINOD KUMAR, S. K. HALDER, S. K. GUPTA, and SUKHVIR SINGH. "INVESTIGATIONS ON NANOCRYSTALLINE SUPERPARAMAGNETIC PARTICLES OF CoFe2O4." International Journal of Nanoscience 06, no. 06 (December 2007): 515–19. http://dx.doi.org/10.1142/s0219581x07004997.

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Superparamagnetic (SP) crystalline cobalt ferrite ( CoFe 2 O 4) nanoparticles are synthesized by chemical co-precipitation method. Grown nanoparticles are annealed in air at various temperatures in the range 373 K to 1173 K to understand the variation in properties in nanoregion. Physical properties are analyzed for crystalline phase, crystallite size, particle size, shape, magnetization and relaxation behavior by using various characterization techniques viz. X-ray diffractometer (XRD), transmission electron microscope (TEM), vibrating sample magnetometer (VSM) and electron paramagnetic resonance (EPR). Annealing effect on various physical properties of particles are investigated. Particles are used in the development of stable ferrofluid.

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GHANASHYAM KRISHNA, M., A. HARTRIDGE, and A. K. BHATTACHARYA. "STRUCTURE AND OPTICAL PROPERTIES OF NANOCRYSTALLINE GADOLINIUM DOPED ZIRCONIA THIN FILMS." International Journal of Modern Physics B 16, no. 26 (October 20, 2002): 4017–25. http://dx.doi.org/10.1142/s0217979202014619.

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Transparent sols of crystalline gadolinium doped zirconia particles with the general formula Zr 1 - x Gd x O 2 - x/2 (where x = 0–0.20), were prepared by a hydrothermal sol-gel method using cheap inorganic precursors. The composition, structure, crystallite size and lattice parameters of the crystalline dried sol particles and heated powders were studied. Thin films were deposited on quartz substrates using a simple dipping process and the structure, composition and crystallite size found to be identical to the powders with respect to the variation in temperature. Spectral transmittance studies showed that the films were transparent in the region between 400 and 1100 nm. The refractive index increased with the increase in annealing temperature, varying between 1.56 and 1.74. Optical band gap calculations gave band of 5.52 to 5.55 eV. Refractive indices and optical band gaps were compared with those of films containing other lanthanide dopants previously reported in the literature.

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Davranov, Kakhramon, Mina J. Tabak, Dzhamil Ch Diyarov, Abdumurod Sattarov, and Kamola A. Gulyamova. "Oospora lactic lipase: Isolation and properties." Collection of Czechoslovak Chemical Communications 55, no. 8 (1990): 2110–17. http://dx.doi.org/10.1135/cccc19902110.

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Lipase (EC 3.1.1.3) of Oospora lactic UzLM-2 was purified by ammonium sulfate (0.40-0.80) fractionation, gel-filtration on Sephadex G-100, column chromatography on DEAE-Sephadex and CM-Sephadex, gel-filtration on Sephadex G-75 and was finally crystallized in concentrated aqueous solution. Crystalline preparation of the enzyme is homogeneous at disc-electrophoresis and ultracentrifugation. Sedimentation coefficient (S20w) is 3.6 S, isoelectric point (pI) at pH 4.2 and molecular mass of the enzyme is 40-43 kD. Amino acid composition analysis showed that none of sulfur-containing amino acids were detected in the crystalline enzyme, but it contains about 8% of carbohydrates and a small amount of lipids. Lipase from Oospora lactic was most active at pH 7.5 and 37 °C in olive oil, stable in the range of pH from 5.7 to 8.0 at 30-40 °C for 18 h and retained stability at 50 °C for 10 min.

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Kayani, Zohra Nazir, Atiqa Aslam, Rabia Ishaque, Syeda Nosheen Zahra, Hifza Hanif, Noor-Ul-Ain Maken, and Hajra Khan. "The effect of the withdrawal speed on properties of nickel oxide thin films." Zeitschrift für Kristallographie - Crystalline Materials 234, no. 10 (October 25, 2019): 647–55. http://dx.doi.org/10.1515/zkri-2019-0028.

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Abstract Nickel oxide thin films have been prepared by sol-gel dip-coating technique on glass substrate. It is shown that nickel oxide thin films have poly crystalline nature. Nickel oxide thin films exhibit high transmission (39–85%) in the wavelength range of 400–900 nm, strong absorption between 300 and 400 nm wavelengths and decrease of band gap values are in the range 3.69–3.27 eV with increase of withdrawal speed. High band gap at low withdrawal speed is because of the small average crystallite size, which decreases with increase in withdrawal speed. The SEM micrograph shows cubic crystallites and surface of thin films become dense, smooth and homogeneous with an increase in withdrawal speed. Assessment of nickel oxide deposition conditions provides gateway for effective and cheap solar cells.

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Halperin, Avi, and David R. M. Williams. "Liquid-crystalline polymers: interfacial properties." Faraday Discussions 98 (1994): 295. http://dx.doi.org/10.1039/fd9949800295.

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Kim, Jeonghan, Bruce M. Novak, and Alan John Waddon. "Liquid Crystalline Properties of Polyguanidines." Macromolecules 37, no. 22 (November 2004): 8286–92. http://dx.doi.org/10.1021/ma0493527.

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Trnovcová, V., M. Kubliha, A. Kokh, P. P. Fedorov, and R. M. Zakalyukin. "Electrical properties of crystalline borates." Russian Journal of Electrochemistry 47, no. 5 (May 2011): 531–36. http://dx.doi.org/10.1134/s1023193511050156.

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Kwon, T. H. "Thermodynamic properties of crystalline KCl." Canadian Journal of Physics 67, no. 7 (July 1, 1989): 664–68. http://dx.doi.org/10.1139/p89-121.

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Thermodynamic functions of crystalline KCl have been evaluated using a localized model characterized by a pseudopotential and direct Brillouin zone sums. Numerical results are compared with available experimental data for adiabatic compressibility, the linear thermal expansion coefficient, specific heat at constant volume, and specific heat at constant pressure. Calculated results show excellent agreement with experimentally observed data.

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Petersen, Anne Ugleholdt, Martyn Jevric, Richard J. Mandle, Martin Drøhse Kilde, Frederik P. Jørgensen, John W. Goodby, and Mogens Brøndsted Nielsen. "Liquid-Crystalline Properties of Thioesters." Australian Journal of Chemistry 71, no. 6 (2018): 422. http://dx.doi.org/10.1071/ch17540.

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An extension of a new method for forming thioesters with mesomorphic properties has been described, whereby the treatment of aryl tert-butylthioethers with long-chain acid chlorides in the presence of bismuth triflate afforded simple derivatives in good yields. This method in the case of 1-cyanoazulenes was, however, complicated by a competitive Friedel–Crafts-type acylation side reaction at the 3-position. Long-chain derivatives of cyanobiphenyl attached through a thioester linkage exhibited mesophases comparable with their ester analogues. The use of shorter chains to decorate the cyanobiphenyl moiety did not produce mesophasic behaviour, unlike their ester analogues. The cyanobiphenyl derivatives showing mesophasic behaviour were studied by small-angle X-ray diffraction, showing alignment for molecules possessing a smectic A phase. It was found that the layer spacing in the smectic A phase was ~1.5 times the length of the molecule, owing to antiparallel pairing arising from π-stacking between neighbouring units. Calculations suggest these derivatives should exhibit large dielectric anisotropy; however, instability made an exact value difficult to determine. For potential use in a liquid crystal display (LCD), the thioester holds some promise, although this may be limited by the relative stability of the thioester functionality.

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Amin, Muhammad, Saadat A. Siddiqi, Ahmad Ashfaq, Murtaza Saleem, Shahid M. Ramay, Asif Mahmood, and Yousef S. Al-Zaghayer. "Study of structural and magnetic properties of melt spun Nd2Fe13.6Zr0.4B ingot and ribbon." Modern Physics Letters B 29, no. 35n36 (December 30, 2015): 1550250. http://dx.doi.org/10.1142/s0217984915502504.

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Nd2Fe[Formula: see text]Zr[Formula: see text]B hard magnetic material were prepared using arc-melting technique on a water-cooled copper hearth kept under argon gas atmosphere. The prepared samples, Nd2Fe[Formula: see text]Zr[Formula: see text]B ingot and ribbon are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) for crystal structure determination and morphological studies, respectively. The magnetic properties of the samples have been explored using vibrating sample magnetometer (VSM). The lattice constants slightly increased due to the difference in the ionic radii of Fe and that of Zr. The bulk density decreased due to smaller molar weight and low density of Zr as compared to that of Fe. Ingot sample shows almost single crystalline phase with larger crystallite sizes whereas ribbon sample shows a mixture of amorphous and crystalline phases with smaller crystallite sizes. The crystallinity of the material was highly affected with high thermal treatments. Magnetic measurements show noticeable variation in magnetic behavior with the change in crystallite size. The sample prepared in ingot type shows soft while ribbon shows hard magnetic behavior.

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Ahvenainen, Patrik, and Ritva Serimaa. "Crystallinity fitting using cellulose crystallite models." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1135. http://dx.doi.org/10.1107/s2053273314088640.

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Cellulose is the most abundant biopolymer on Earth and hence it has enormous potential as a source of renewable energy. The nanoscale properties of cellulose are also import for the wood and papermaking industries. The atomic level structure of naturally occurring cellulose Iβ allomorph is well known [1] and this atomistic model is employed in this study for the cellulose unit cell structure. The cellulose crystallinity cannot be measured directly with scattering methods, but the crystallinity of the sample can be estimated by fitting models of crystalline and amorphous contributions to the sample intensity profile. The crystallinity fitting can be enhanced by improving the cellulose fitting model or the amorphous model. We focus on the cellulose crystallite model. The nanoscale level organization of crystalline cellulose in different plant materials is less well established that the unit cell structure of cellulose Iβ. Information on the texture of the sample is obtained efficiently by measuring the sample with a two-dimensional detector. The two-dimensional diffraction pattern can be used to obtain a wealth of information in one measurement, including the crystallite size, crystallite orientation and the crystallinity of the sample. The small size of cellulose crystallites in the wood cell wall limits the information obtainable from the diffraction pattern as the diffraction peaks widen and overlap. The overlapping of certain diffraction peaks can be studied at least qualitatively by computing the diffraction patterns from crystallite models of varying dimensions. Different models for cellulose crystallite have been suggested in the literature, such as the 36 chain model [2]. We investigate how the crystallinity fitting is influenced by the selected cellulose crystallite model and evaluate the suitability of different models to experimental X-ray scattering data of plant material, wood and highly crystalline cellulose.

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Kushnerov, O. I., and V. F. Bashev. "Structure, thermal and electrical properties of Fe-B-Co-Nb-Ni-Si high-entropy metallic glass." Journal of Physics and Electronics 28, no. 1 (September 10, 2020): 49–54. http://dx.doi.org/10.15421/332009.

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New nanostructured Fe25B17.5Co21.35Nb3.65Ni25Si7.5 high-entropy metallic glass is synthesized by dint of splat-quenching technique. The estimated cooling rate is ~106 K/s. The coherently scattering domain size (crystallite size) of films of Fe 25B17.5Co21.35Nb3.65Ni25Si7.5 high-entropy metallic glass estimated by the Sherer formula is ~ 3 nm. The high-entropy metallic glass shows a high temperature of glass transition Tg ~ 800 K and the initial temperature of crystallization Tx ~ 863 K. After annealing to ~ 1010 K (above the crystallization temperature) and subsequent slow cooling, the amorphous films crystallize with the formation of several crystalline phases. The temperature dependencies of electrical resistivity of the Fe25B17.5Co21.35Nb3.65Ni25Si7.5 films indicate the occurrence of phase transformations. The phase transformation temperature (temperature of crystallization) is ~ 869 K. This value agrees well with the value obtained from the differential thermal analysis.

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UJIIE, Seiji, Yutaka TANAKA, Yumi YANO, Akira MORI, and Kazuyoshi IIMURA. "Thermal and Liquid Crystalline Properties of Ionic Liquid Crystalline Systems." KOBUNSHI RONBUNSHU 63, no. 1 (2006): 11–18. http://dx.doi.org/10.1295/koron.63.11.

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Shyu, Jiin-Jyh, and Hsin-Wei Peng. "Crystallization and dielectric properties of SrO–BaO–Nb2O5–GeO2 tungsten–bronze glass–ceramics." Journal of Materials Research 16, no. 7 (July 2001): 2057–63. http://dx.doi.org/10.1557/jmr.2001.0282.

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The crystallization and dielectric properties of SrO–BaO–Nb2O5–GeO2 glass–ceramics were investigated. One- and two-stage heat-treatment methods were used to convert the parent glass to glass–ceramics. Strontium barium niobate (SBN) with a tetragonal tungsten-bronze structure formed as the major crystalline phase. When the crystallizing temperature/time was increased, the secondary crystalline BaGe2O5 phase coexisted with SBN. BaGe2O5 formed as a surface layer grown from the surface into the interior of the sample. The dendritic morphology of SBN crystals was examined. The glass–ceramics crystallized by two-stage heat treatment have higher dielectric constants than those crystallized by one-stage heat treatment. The highest dielectric constant that was obtained in the present glass–ceramics was 320. The glass–ceramics showed relaxor-type dielectric behavior.

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Dontsova, Tetiana, Anastasiya Kutuzova, and Ahmad Hosseini-Bandegharaei. "Characterization and Properties of Titanium(IV) Oxide, Synthesized by Different Routes." Chemistry & Chemical Technology 15, no. 4 (November 25, 2021): 465–74. http://dx.doi.org/10.23939/chcht15.04.465.

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The article considers the influence of precursor type and sol-gel synthesis conditions of TiO2 on its properties. The obtained TiO2 samples were characterized by X-ray diffraction methods, electron microscopy, as a result of which it was found that all the obtained TiO2 powders have the crystallite size in a nanorange of 2.5–17 nm. It was shown that sorption-photocatalytic properties of TiO2 significantly depend on a phase composition, surface acidity, specific surface area and porosity. It was found that the amorphous TiO2 has improved adsorption properties, while crystalline TiO2 is characterized by enhanced photocatalytic properties. Determined acidic nature of the TiO2 surface explains the better sorption and photocatalysis relative to the cationic dye.

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Li, Guiwei, Ji Zhao, Jerry Ying Hsi Fuh, Wenzheng Wu, Jili Jiang, Tianqi Wang, and Shuai Chang. "Experiments on the Ultrasonic Bonding Additive Manufacturing of Metallic Glass and Crystalline Metal Composite." Materials 12, no. 18 (September 14, 2019): 2975. http://dx.doi.org/10.3390/ma12182975.

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Ultrasonic vibrations were applied to weld Ni-based metallic glass ribbons with Al and Cu ribbons to manufacture high-performance metallic glass and crystalline metal composites with accumulating formation characteristics. The effects of ultrasonic vibration energy on the interfaces of the composite samples were studied. The ultrasonic vibrations enabled solid-state bonding of metallic glass and crystalline metals. No intermetallic compound formed at the interfaces, and the metallic glass did not crystallize. The hardness and modulus of the composites were between the respective values of the metallic glass and the crystalline metals. The ultrasonic bonding additive manufacturing can combine the properties of metallic glass and crystalline metals and broaden the application fields of metallic materials.

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Li, Bing, Xue Mei Qin, and Bao Shan Shi. "Measurement and Analysis on Dynamics Cold Crystallization Parameter of High-Density Polyethylene (HDPE) Sheet by Vibration Force Field." Applied Mechanics and Materials 103 (September 2011): 447–51. http://dx.doi.org/10.4028/www.scientific.net/amm.103.447.

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Physics mechanics properties of polymer materials don’t only depend on their chemical constitution, molecular weight and distribution of molecular weight, but also depend on their agglomerate configuration. The effect of vibration on the microstructure and mechanical properties of high-density polyethylene (HDPE) sheets, obtained through vibration plasticating extruder in low temperature, were studied systematically. Crystalline polymer is analyzed by differential scanning calorimetry(DSC), wide angle X ray diffraction(WAXD). The test result which represents parameters of crystalline structure is helped to judge the outside factors for crystalline structure, such as melting point, crystallinity and heat of fusion by DSC and crystallinity, crystal plane distance and grain size by WAXD, and canning electron microcopy (SEM). The results indicate that the vibration extrudate in low temperature has higher crystallinity, perfect crystallite, and strong inter-spherulite ties.

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Honarvar Nazari, M., Abolghasem Ataie, and S. A. Seyyed Ebrahimi. "Nano-Crystalline Barium Hexaferrite Powders Prepared by Mechanical Alloying Using Acetate Precursor." Key Engineering Materials 368-372 (February 2008): 610–12. http://dx.doi.org/10.4028/www.scientific.net/kem.368-372.610.

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Nano-crystalline barium hexaferrite powders have been prepared by mechanical alloying of nFe2O3+Ba(CH3COO)2 with Fe/Ba molar ratios of 10-12 and subsequent heat treatment. Thermal behavior, phase composition, morphology and magnetic properties of samples were studied using DTA/TGA, XRD, SEM and VSM, respectively. Nano-crystalline Ba-hexaferrite with a mean crystallite size of 46 nm and magnetic properties as high as Ms = 73.9 A.m2/kg and Hci = 334.2 kA/m was formed for mixture of 5.5Fe2O3+Ba(CH3COO)2 which was milled for 48 h and then annealed at 1100 °C.

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Meier, Wolfgang, and Heino Finkelmann. "Liquid Crystal Elastomers with Piezoelectric Properties." MRS Bulletin 16, no. 1 (January 1991): 29–31. http://dx.doi.org/10.1557/s0883769400057870.

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During the last few years, liquid crystalline elastomers (LCEs) have been systematically produced by cross-linking liquid crystalline side-chain polymers. In these networks, a liquid crystalline molecule is fixed at each monomeric unit. LCEs exhibit a novel combination of properties. Due to liquid crystalline groups, they show anisotropic liquid crystalline properties similar to conventional liquid crystals (LCs); but due to the three-dimensional network-structure of the polymer chains, they show typical elastomer properties, such as rubber elasticity or shape stability. One exceptional property of this combination is demonstrated when a mechanical deformation to the LCE causes macroscopically uniform orientation of the long molecular axis of the LC units (the so-called “director”).This response of the LC-phase structure to an applied mechanical field is similar to the effect of electric or magnetic fields on low molecular weight liquid crystals (LMLC), as illustrated in Figure 1. Figure la shows an undeformed LCE. Because of the non-uniform orientation of the director, the sample scatters light strongly so the elastomer is translucent like frosted glass. On the other hand, applying a mechanical field the director becomes uniformly aligned and the sample is transparent (Figure 1b). Such a macroscopically ordered rubber exhibits optical properties very similar to single crystals. These propertie s of LCEs offer new prospects for technical application, e.g., in nonlinear and integrated optics.

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Wang, Wei-Kai, Kuo-Feng Liu, Pi-Chuen Tsai, Yi-Jie Xu, and Shih-Yung Huang. "Influence of Annealing Temperature on the Properties of ZnGa2O4 Thin Films by Magnetron Sputtering." Coatings 9, no. 12 (December 14, 2019): 859. http://dx.doi.org/10.3390/coatings9120859.

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Zinc gallate (ZnGa2O4) thin films were grown on sapphire (0001) substrate using radio frequency (RF) magnetron sputtering. After the thin film deposition process, the grown ZnGa2O4 was annealed at a temperature ranging from 500 to 900 °C at atmospheric conditions. The average crystallite size of the grown ZnGa2O4 thin films increased from 11.94 to 27.05 nm as the annealing temperature rose from 500 to 900 °C. Excess Ga released from ZnGa2O4 during thermal annealing treatment resulted in the appearance of a Ga2O3 phase. High-resolution transmission electron microscope image analysis revealed that the preferential crystallographic orientation of the well-arranged, quasi-single-crystalline ZnGa2O4 (111) plane lattice fringes were formed after the thermal annealing process. The effect of crystallite sizes and lattice strain on the width of the X-ray diffraction peak of the annealed ZnGa2O4 thin films were investigated using Williamson-Hall analysis. The results indicate that the crystalline quality of the deposited ZnGa2O4 thin film improved at higher annealing temperatures.

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Kosmulski, Marek, Edward Mączka, and Leszek Ruchomski. "Synthesis and Properties of SBA-15 Modified with Non-Noble Metals." Colloids and Interfaces 2, no. 4 (November 14, 2018): 59. http://dx.doi.org/10.3390/colloids2040059.

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Modification of SBA-15 with non-noble metal leads to functional materials, which can be applied as gas sensors, adsorbents, and catalysts of various reactions. The new materials contain up to four various metals, which are deposited consecutively or simultaneously at various concentrations ranging from a fraction of 1% to an amount that is comparable with the mass of silica-support. These materials contain metals at various oxidation levels, usually as oxides, which occur in crystalline form (a typical crystallite size of about 10 nm matches the width of the SBA-15 channels), but in a few other materials, crystalline metal compounds have not been detected. Many researchers have provided detailed physico- chemical characteristics of SBA-15 modified with non-noble metals by the means of various microscopic and spectroscopic techniques.

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Mandelkern, Leo. "THE ROLE OF ELASTOMERS IN THE STUDY OF POLYMER CRYSTALLIZATION." Rubber Chemistry and Technology 66, no. 3 (July 1, 1993): G61—G75. http://dx.doi.org/10.5254/0035-9475-66.3.g61.

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Abstract Crystallization in polymers involves the development of three-dimensional order in the system. In this respect crystalline polymers resemble very closely the crystalline state of monomeric systems. In contrast to low molecular weight systems, however1 polymers never crystallize completely. The crystallinity level can vary from a few to 90% depending on the molecular constitution of the polymer chains and the external crystallization conditions. Consequently, a polycrystalline system having a complex morphology develops. When a polymer system crystallizes, either quiescently, or when held in a deformed state, there are major changes in properties from the typical rubber-like elasticity of noncrystalline (amorphous) polymers. These changes are particularly evident in many physical and mechanical properties. Therefore, it is important to understand the nature of the crystallization process and the structure and morphology that evolves. In addition to their intrinsic scientific interest these factors have great bearing on properties and the end-uses of polymeric substances. In this connection, elastomers, particularly natural rubber, have played a vital role that has led to our present understanding of the crystallization behavior of polymers, and the properties of the crystalline state. The significance of these pioneering contributions has not been generally recognized in today's study of the diverse number of crystalline polymers that constitute the present world of commerce.

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Awang, Ainun Jariah, Husin Wagiran, and Abd Khamim Ismail. "Structural Properties of Al₂O₃:C:Mg Thin Films by RF Magnetron Sputtering." Advanced Materials Research 1107 (June 2015): 661–66. http://dx.doi.org/10.4028/www.scientific.net/amr.1107.661.

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Carbon doped aluminum oxide co-doped with magnesium (Al2O3:C:Mg) thin films were deposited using radio frequency magnetron sputtering method on Si (100) substrates. The deposition chamber temperature was manipulated to allow control over the crystalline phase. The crystalline phase of deposited thin films were determined by x-ray diffraction (XRD) technique. Slight change in crystallite size was observed with respect to the increasing deposition chamber temperature. Fourier transform infrared (FTIR) analyses indicated a negligible interfacial SiO2 growth during deposition. Transmission spectra of FTIR showed the bond and functional group of deposited thin films.

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40

Huang, T. C. "Correlations Between X-Ray Microstructures and Magnetic Properties of CoCrTa Alloy thin Films." Advances in X-ray Analysis 31 (1987): 107–12. http://dx.doi.org/10.1154/s037603080002190x.

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AbstractThin film structures determined by X-ray reflection and transmission diffractometer methods has been used to co rrelate with th e magnetic p roperties of CoCrTa thin films. Well-crystallized CoCrTa alloy particles with strong h.c.p. c-axis preferred oriented normal to the film surfaces were found to be mainly responsible for the perpendicular magnetic anisotropy observed in specimens IL and 8L, whereas poorly crystallized CoCrTa particles in the 150Å thick magnetic layers of a third specimen 33L have led to an observed longitudinal magnetization. Microstrains generated by the crystalline - amorphous interface stresses induced an enhanced perpendicular magnetic anisotropy in specimen 8L. Values of crystallite size D determined from the Warren-Averbach analysis were correlated with the coercivities He. Analysis of the He vs. D curve indicated th a t the critical particle size for a magnetic multi- to single-domain transition was 270± 25Å. The retention in coercivity (Hc=175 Oe) at a small particle size (D=75Å) in specimen 8L suggested that strong interparticle interactions existed among the wellcrystallized CoCrTa particles. A much smaller retention in coercivity (Hc=90 Oe) at D=70Å of specimen 33L indicated the inter particle interactions in poorly crystallized CoCrTa layers were relatively weak.

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41

Ketoja, Jukka, Sami Paavilainen, James Liam McWhirter, Tomasz Róg, Juha Järvinen, and Ilpo Vattulainen. "Mechanical properties of cellulose nanofibrils determined through atomistic molecular dynamics simulations." Nordic Pulp & Paper Research Journal 27, no. 2 (May 1, 2012): 282–86. http://dx.doi.org/10.3183/npprj-2012-27-02-p282-286.

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Abstract We have carried out atomistic molecular dynamics simulations to study the mechanical properties of cellulose nanofibrils in water and ethanol. The studied elementary fibrils consisted of regions having 34 or 36 cellulose chains whose cross-sectional diameter across the fibril was roughly 3.4 nm. The models used in simulations included both crystalline and non-crystalline regions, where the latter were designed to describe the essentials parts of amorphous cellulose nanofibrils. We examined different numbers of connecting chains between the crystallites, and found out that the elastic constants, inelastic deformations, and strength of the fibril depend on this number. For example, the elastic modulus for the whole fibril can be estimated to increase by 4 GPa for each additional connecting chain.

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42

Deraz, N. M., and A. Alarifi. "Structural, Surface and Catalytic Properties of Nano-Sized Ceria Catalysts." Adsorption Science & Technology 27, no. 4 (May 2009): 413–22. http://dx.doi.org/10.1260/026361709790252605.

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Well-dispersed uniform spheres of crystalline CeO2 were prepared by calcining precursor particles obtained by heating ammonium cerium nitrate for 4 h. These spherical substrates were examined using XRD and TEM methods, and by nitrogen adsorption studies at −196 °C. Subsequently, such cerium oxide particles prepared by calcination at 400–600 °C were used as catalysts for the conversion of isopropanol at 250–450 °C, using a flow method. The results obtained showed that increasing the heating temperature of the system investigated from 400 °C to 600 °C stimulated the formation of a well-crystallized CeO2 phase having a crystallite size varying between 10 and 20 nm. Both the surface area and catalytic activity of cerium oxide were found to decrease on increasing the calcination temperature. All solids investigated behaved as dehydrogenation catalysts which were selective towards the formation of acetone. The heat treatment did not alter the mechanism of dehydrogenation of isopropanol, but changed the concentration of active sites involved in the catalyzed reaction without altering their energetic nature.

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43

Gaba, Eric Worlawoe, Bernard O. Asimeng, Elsie Effah Kaufmann, Solomon Kingsley Katu, E. Johan Foster, and Elvis K. Tiburu. "Mechanical and Structural Characterization of Pineapple Leaf Fiber." Fibers 9, no. 8 (August 6, 2021): 51. http://dx.doi.org/10.3390/fib9080051.

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Evidence-based research had shown that elevated alkali treatment of pineapple leaf fiber (PALF) compromised the mechanical properties of the fiber. In this work, PALF was subjected to differential alkali concentrations: 1, 3, 6, and 9% wt/wt to study the influence on the mechanical and crystal properties of the fiber. The crystalline and mechanical properties of untreated and alkali-treated PALF samples were investigated by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), and tensile testing analysis. The XRD results indicated that crystal properties of the fibers were modified with 6% wt/wt alkali-treated PALF recording the highest crystallinity and crystallite size of 76% and 24 nm, respectively. The FTIR spectra suggested that all alkali-treated PALF samples underwent lignin and hemicellulose removal to varying degrees. An increase in the crystalline properties improved the mechanical properties of the PALF treated with alkali at 6% wt/wt, which has the highest tensile strength (1620 MPa). Although the elevated alkali treatment resulted in decreased mechanical properties of PALF, crystallinity generally increased. The findings revealed that the mechanical properties of PALF not only improve with increasing crystallinity and crystallite size, but are also dependent on the intermediate bond between adjacent cellulose chains.

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Zhou, Xiaoling, and Changqing Chen. "Molecular dynamic simulations of the mechanical properties of crystalline/crystalline and crystalline/amorphous nanolayered pillars." Computational Materials Science 101 (April 2015): 194–200. http://dx.doi.org/10.1016/j.commatsci.2015.01.033.

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45

Atmani, H., S. Grognet, J. Teillet, K. Zellama, and R. Zuberek. "Structural and magnetic properties of nitrided finemet-type ribbons." Canadian Journal of Physics 77, no. 9 (February 1, 2000): 731–36. http://dx.doi.org/10.1139/p99-029.

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Nitriding thermochemical treatment under suitable parameters is used to nano-crystallize Fe73.5Cu1Nb3Si13.5B9 ribbon. This new kind of treatment leads to finer nano-structure and modifies the structural parameters of the α-Fe(Si) phase, obtained during the treatment. The magnetic properties are also improved; specific magnetization at room temperature and Curie temperature of the crystalline phase increase, and the magnetostriction constant becomes smaller. The nitrogenation seems to offer a new way to obtain nanostructured ribbons. PACS No.: 75.70

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46

Berger, C., K. Hasselbach, J. C. Lasjaunias, C. Paulsen, and P. Germi. "Magnetic properties of quasi-crystalline, amorphous and crystalline AlMn(Si) alloys." Journal of the Less Common Metals 145 (December 1988): 565–72. http://dx.doi.org/10.1016/0022-5088(88)90314-1.

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47

Damrawi, G. El. "Â¬Â¬Chromium fluoride-containing bioactive glasses: Structure and properties." JOURNAL OF ADVANCES IN PHYSICS 13, no. 4 (August 1, 2017): 4868–48775. http://dx.doi.org/10.24297/jap.v13i5.6042.

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Bioglasses in the system 24.5Na2O.24.5CaO.6P2O5.xCrF2.(45-x)SiO2 have been studied in the composition region of x= 0-10 mol%. CrF2. Glass of molar ratio (Ca+Na)/SiO2 ~1.1 is the base material for the glasses containing different CrF2 concentrations. X-ray diffraction (XRD), differential scanning calorimetriy (DSC), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and Vicher hardness (Hv) measurements have been carried out. Crystalline feature of the glasses is followed up by XRD spectroscopy. It is found that crystallinity was enhanced via CrF2 addition. More enhancement was confirmed via thermal heat treatment process. Increasing CrF2 and sintering temperature will induce new ordered phases which will be distributed in the main glassy phase. Well formed flouroapatite (Ca5(PO4)3F and wollastonite Ca3Cr2(SiO4)3 phases containing fluorine and chromium ions are evidenced in CrF2 containing glasses. Increasing glass transition temperature Tg and hardness number Hv upon increasing CrF2 concentration was discussed on bases of formation of additional bonds by the effect of CrF2 molecules. The measured temperature window between Tc and Tg was found to have a great influence in material structure. Wide window is a feature of amorphous glass which free from CrF2. The window scale is found to quickly decrease with increasing CrF2, since crystalline phases are already formed in glasses containing CrF2. Formation of crystalline intermediate phases with more shielded silicate and phosphate structural is considered as the main reason for increasing Tg and (Hv) of the glasses. EDS as well as XRD analyzed spectra confirm that crystalline wollastonite of calcium inosilicate mineral (CaSiO3) phase is well formed. The wollastonite species is evidenced to contain small amounts of chromium and fluorine ions which are substituting for calcium cations. Wollastonite phases with Cr/Si=1 is the most dominant type. This ratio is a characteristic feature of crystalline CaSiO3 species. Small concentration from fluorine ions are involved in apatite phases. Presence of both crystalline apatite and wollastonite in the sample matrix promotes its biocompatibility, particularly orthopedic bioactivity. As a consequence, some of investigated glasses are recommended to be applicable in dental field of applications. This depends on its own crystallinity, hardness, its apatite and wollastonite concentration as biocompatible phases in the crystallized glass

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REY, C., A. HINA, S. SOMRANI, M. JEMAL, and M. J. GLIMCHER. "CHEMICAL PROPERTIES OF POORLY CRYSTALLINE APAPITIES." Phosphorus Research Bulletin 6 (1996): 67–70. http://dx.doi.org/10.3363/prb1992.6.0_67.

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von Berlepsch, Hans, Sven Möller, and Lars Dähne. "Optical Properties of Crystalline Pseudoisocyanine (PIC)." Journal of Physical Chemistry B 105, no. 24 (June 2001): 5689–99. http://dx.doi.org/10.1021/jp004581q.

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Yoshii, K., M. Mizumaki, K. Matsumoto, S. Mori, N. Endo, H. Saitoh, D. Matsumura, T. Kambe, and N. Ikeda. "Magnetic properties of single crystalline YbFe2O4." Journal of Physics: Conference Series 428 (April 5, 2013): 012032. http://dx.doi.org/10.1088/1742-6596/428/1/012032.

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Journal articles on the topic 'Crystalline properties'

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