scholarly journals Synthesis, structure and physical properties of the new layered oxyselenides Bi 2 LnO 4 Cu 2 Se 2 (Ln = rare earth)

2020 ◽  
Vol 7 (10) ◽  
pp. 201078
Author(s):  
Shugang Tan ◽  
Chenhao Gao ◽  
Cao Wang ◽  
Qiang Jing ◽  
Tong Zhou ◽  
...  
Keyword(s):  
Physical Properties ◽  
Dft Calculation ◽  
Layered Compounds ◽  
Electric Transport ◽  
X Ray Diffraction ◽  
Iron Based Superconductors ◽  
Principle Calculation ◽  
First Principle Calculation ◽  
X Ray ◽  
Bulk Magnetization

We have synthesized a new series of layered oxyselenides Bi 2 LnO 4 Cu 2 Se 2 (Ln=Nd, Sm, Eu, Dy, Er, Yb). Their crystal structures and physical properties were studied through X-ray diffraction, electric transport measurements, bulk magnetization and first-principle calculation. All these compounds have a tetragonal structure with space group I4/mmm. They exhibit hole-type metallic behaviours which is also verified by the DFT calculation. The new Bi 2 LnO 4 -type block in these compounds may give people some enlightenment in synthesizing new iron-based superconductors or other layered compounds.

Microstructure and Physical Properties of Clay-Polymer Composites

2000 ◽  
Vol 628 ◽  
Author(s):  
T.N. Blanton ◽  
D. Majumdar ◽  
S.M. Melpolder
Keyword(s):  
Composite Materials ◽  
Physical Properties ◽  
Polymer Composites ◽  
Basal Plane ◽  
X Ray Diffraction ◽  
X Ray ◽  
Layered Clay

ABSTRACTClay-polymer nanoparticulate composite materials are evaluated by the X-ray diffraction technique. The basal plane spacing provided information about the degree of intercalation and exfoliation of the 2: 1 layered clay structure. Both intercalation and exfoliation are controlled by the identity of the polymer and the clay:polymer ratio.

scholarly journals Thermal, Structural, and Physical Properties of Freeze Dried Tropical Fruit Powder

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
K. A. Athmaselvi ◽  
C. Kumar ◽  
M. Balasubramanian ◽  
Ishita Roy
Keyword(s):  
Particle Size ◽  
Physical Properties ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Tropical Fruit ◽  
X Ray ◽  
Freeze Dried ◽  
Fruit Powder ◽  
Lcr Meter

This study evaluates the physical properties of freeze dried tropical (guava, sapota, and papaya) fruit powders. Thermal stability and weight loss were evaluated using TGA-DSC and IR, which showed pectin as the main solid constituent. LCR meter measured electrical conductivity, dielectric constant, and dielectric loss factor. Functional groups assessed by FTIR showed presence of chlorides, and O–H and N–H bonds in guava, chloride and C–H bond in papaya, and chlorides, and C=O and C–H bonds in sapota. Particle size and type of starch were evaluated by X-ray diffraction and microstructure through scanning electronic microscopy. A semicrystalline profile and average particle size of the fruit powders were evidenced by X-ray diffraction and lamellar/spherical morphologies by SEM. Presence of A-type starch was observed in all three fruits. Dependence of electric and dielectric properties on frequency and temperature was observed.

Lithofacies Analysis and Qualitative Minerology of the Sediments of #3 Well in the Greater Ughelli Depobelt, Niger Delta Basin

2021 ◽  
Vol 13 (2) ◽  
pp. 601-610
Author(s):  
K. Itiowe ◽  
R. Oghonyon ◽  
B. K. Kurah
Keyword(s):  
Physical Properties ◽  
Clay Minerals ◽  
Niger Delta ◽  
Reservoir Quality ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sandy Shale ◽  
Heterogeneous Nature ◽  
Niger Delta Basin ◽  
Shaly Sandstone

The sediment of #3 Well of the Greater Ughelli Depobelt are represented by sand and shale intercalation. In this study, lithofacies analysis and X-ray diffraction technique were used to characterize the sediments from the well. The lithofacies analysis was based on the physical properties of the sediments encountered from the ditch cuttings.  Five lithofacies types of mainly sandstone, clayey sandstone, shaly sandstone, sandy shale and shale and 53 lithofacies zones were identified from 15 ft to 11295 ft. The result of the X-ray diffraction analysis identified that the following clay minerals – kaolinite, illite/muscovite, sepiolite, chlorite, calcite, dolomite; with kaolinite in greater percentage. The non-clay minerals include quartz, pyrite, anatase, gypsum, plagioclase, microcline, jarosite, barite and fluorite; with quartz having the highest percentage. Therefore, due to the high percentage of kaolinite in #3 well, the pore filing kaolinite may have more effect on the reservoir quality than illite/muscovite, chlorite and sepiolite. By considering the physical properties, homogenous and heterogeneous nature of the #3 Well, it would be concluded that #3 Well has some prospect for petroleum and gas exploration.

scholarly journals Solvent Concentration Effect on Powder X-Ray Diffraction and Dissolution Profiles of Acyclovir-Nicotinamide Cocrystals

2017 ◽  
Vol 7 (04) ◽  
Author(s):  
Setyawan D. ◽  
Siswandono Siswandono ◽  
Winantari A. N. ◽  
Zu’aimah K.
Keyword(s):  
Physical Properties ◽  
Oral Bioavailability ◽  
Ethanol Concentration ◽  
Antiviral Agent ◽  
X Ray Diffraction ◽  
Solvent Concentration ◽  
Solubility In Water ◽  
X Ray ◽  
Dissolution Properties ◽  
Slurry Method

Objective : Acyclovir (ACV) is well-known antiviral agent that has absorption problem, mainly due to its poor solubility in water and oral bioavailability. To improve acyclovir physical properties, especially dissolution properties, acyclovirnicotinamide(NCT) cocrystal was formed. Methods : ACV-NCT cocrystal was prepared using slurry method using ethanol as solvent with different concentration. The ACV-NCT cocrystal from each sample groups was characterized using powder X-ray diffraction (PXRD), and then dissolution properties evaluated. Results : Each ACV-NCT cocrystals prepared from slurry method with different ethanol concentrations have different PXRD profile. Dissolution analysis (ED15) showed that ACV-NCT cocrystallization using slurry methods with 10,0 ml/g as ethanol concentration significantly increase ED15 values compared to acyclovir and acyclovir-nicotinamide physical mixture (α=0,05). Conclusion : ACV-NCT cocrystal successfully formed using slurry method with 10,0 ml/g as optimal ethanol concentration.

Effects of Electron Beam on Structure and Physical Properties of Natural Colorless Topaz

2015 ◽  
Vol 1125 ◽  
pp. 60-63
Author(s):  
Chutharat Paikaew ◽  
Juthamas Inthanont ◽  
Adisak Punyanut ◽  
Ekachai Hoonnivathana ◽  
Pichet Limsuwan ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Electron Beam ◽  
Physical Properties ◽  
Orthorhombic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Spin Resonance ◽  
Function Group ◽  
And Function ◽  
Beam Dose

The purpose of this research was to investigate physical properties, configuration and color of topaz. Topazes were irradiated with electron beam linear accelerator at different dose from 40 to 180 MGy. The color of topaz was analyzed by UV-vis and it was shown that the color of topaz was becoming strong color with increased electron beam dose. Crystal structure and function group of topaz were characterized by X- ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The results showed that the topaz has orthorhombic structure and no other crystalline. After irradiated, topaz released OH indicating higher crystallinity of topaz and this was confirmed with the results of electron spin resonance (ESR). Electron beam dose response of topaz was investigated. ESR results showed that the Al3+ ion was substituted in Si4+ site and Ti3+ impurity in Al4+ site and this result corresponds to the results of FTIR. The experiment result indicated that electron beam could be making defect on crystal structure and color enhancement of topaz.

Physical properties of glycosyl diacylglycerols. 2. X-ray diffraction studies of a homologous series of 1,2-di-O-acyl-3-O-(.alpha.-D-glucopyranosyl)-sn-glycerols

Biochemistry ◽  
1990 ◽  
Vol 29 (34) ◽  
pp. 7799-7804 ◽  
Author(s):  
Arindam Sen ◽  
Sek Wen Hui ◽  
David A. Mannock ◽  
Ruthven N. A. H. Lewis ◽  
Ronald N. McElhaney
Keyword(s):  
Physical Properties ◽  
Homologous Series ◽  
X Ray Diffraction ◽  
X Ray

The Influence of Argon Pressure on the Structural and Physical Properties of LaB6 Films

2011 ◽  
Vol 55-57 ◽  
pp. 1436-1440 ◽  
Author(s):  
Xiao Hua Zhao ◽  
Guang Hui Min ◽  
Jing Xu ◽  
Jie Lin
Keyword(s):  
Physical Properties ◽  
Elasticity Modulus ◽  
Lanthanum Hexaboride ◽  
Argon Pressure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Amorphous Structures ◽  
Crystallization Degree

Lanthanum hexaboride (LaB6) films were deposited on Si (111) substrates by magnetron sputtering method. The characterization of the films was investigated by means of atom force microscopy (AFM), X-ray diffraction (XRD), four-point probe electrical resistance measurement, scratch tester and nano-indentation tester. Influence of argon pressure on physical properties, such as crystallization degree, conductivity and mechanical properties was studied. All the films were smooth and dense. The film crystallites showed a preferential orientation of (100) plane, but the films which were deposited at 2.0 Pa exhibited amorphous structures. LaB6 films which were deposited below 1.5 Pa had excellent conductivity. The bonding strength of the films which were deposited at 1.0 Pa was higher than the others due to the formation of the nano-sized crystals. The hardness and elastic modulus were investigated in connection with the crystalline of LaB6 films. As a result, the films which were deposited at 1.0 Pa had a maximal value of hardness (16.782 Gpa) and elasticity modulus (193.895 Gpa). In a word, the LaB6 films which were deposited at 1.0 Pa have a higher degree of crystalline and more excellent physical properties in comparison with the others. The obtained results will be used synthesizing LaB6 films for applications in low-temperature thermoelectric devices.

Charge transfer associated with lithium insertion in Mo1−yNbyS2 layered compounds

1984 ◽  
Vol 62 (1) ◽  
pp. 10-14 ◽  
Author(s):  
M. A. Py ◽  
R. R. Haering
Keyword(s):  
Voltage Drop ◽  
Structural Disorder ◽  
Host Lattice ◽  
Layered Compounds ◽  
Electrochemical Cells ◽  
X Ray Diffraction ◽  
Electronic Density ◽  
X Ray ◽  
Critical Composition ◽  
Trigonal Prismatic

The Mo1−yNbyS2 layered compounds form solid solutions. The coordination of the Mo and Nb atoms by S atoms is trigonal prismatic over the entire range of composition, 0 ≤ y ≤ 1. The [Formula: see text] band, separated from the other d-bands by a bandgap of the order of 1 eV, contains y empty states per formula unit. For y ≤ 0.6, Li/LixMo1−yNbyS2 electrochemical cells reveal a sharp voltage drop of V(x) at a critical composition x which is correlated to y by [Formula: see text]. This result clearly establishes the transfer of one electron per intercalated lithium (x ≤ 0.6) to the [Formula: see text] band of the host.Electrochemical cells, made with samples whose X-ray diffraction spectra suggest the presence of structural disorder in the host lattice, show a less abrupt voltage drop near xc, in qualitative agreement with the influence of disorder on the electronic density-of-states distribution N(E) near a band edge. The origin of the voltage drop observed for LixMo0.2Nb0.8S2 is not fully established.

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