scholarly journals New Mixed Y0.5R0.5VO4 and RVO4:Bi Materials: Synthesis, Crystal Structure and Some Luminescence Properties

Inorganics ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 94 ◽  
Author(s):  
Leonid Vasylechko ◽  
Andrii Tupys ◽  
Vasyl Hreb ◽  
Volodymyr Tsiumra ◽  
Iryna Lutsiuk ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Binary Systems ◽  
Materials Synthesis ◽  
Lattice Constants ◽  
Cation Radius ◽  
Photoluminescence Studies ◽  
The Impact ◽  
Structure And Microstructure ◽  
Cell Volumes

The results are reported on a precise crystal structure and microstructure determination of new mixed YVO4-based orthovanadates of Y0.5R0.5VO4 (R = Sm, Tb, Dy, Ho, Tm, Yb, Lu) as well as some Bi3+-doped RVO4 (R = La, Gd, Y, Lu) nano- (submicro-) materials. The formation of continuous solid solutions in the YVO4–RVO4 pseudo-binary systems (R = Sm, Tb, Dy, Ho, Tm, Yb, Lu) has been proved. The lattice constants and unit cell volumes of the new mixed orthovanadates were analyzed as a function of R3+ cation radius. The impact of crystal structure parameters on the energy band gap of the materials was studied by means of photoluminescence studies of the Bi3+-doped compounds.

Effect of Errors in Temperature Measurement on the Accuracy of Composition of the Liquid-Vapour Phases and Their Impact on the Calculated Number of Theoretical Stages of Rectification Columns

1992 ◽  
Vol 57 (9) ◽  
pp. 1867-1878
Author(s):  
Ján Dojčanský ◽  
Soňa Bafrncová ◽  
Július Surový
Keyword(s):  
Phase Composition ◽  
Binary Systems ◽  
Equilibrium Temperature ◽  
Systematic Errors ◽  
Operating Conditions ◽  
Rectification Column ◽  
Relative Volatility ◽  
The Impact ◽  
Calculated Number

The effect of random and systematic errors in the determination of the equilibrium temperature on the phase composition in isobaric L-G equilibria was simulated on five binary systems with different size and relative volatility. The impact of the inaccuracies on the calculated number of theoretical stages of a continuously operating rectification column is discussed with respect to the different operating conditions of the separatory process.

Aluminiumbromid-Pyridiniumbromid-Verbindung: Kristallstruktur Kristallstrukturbestimmung von [Tris(pyridinium)bromid]bis(tetrabromoaluminat(III))/ Aluminiumbromide-Pyridiniumbromide Compounds: Crystal Structure Crystal Structure Determination of [Tris(pyridinium)bromide]bis(tetrabromoaluminate(III))

1988 ◽  
Vol 43 (8) ◽  
pp. 963-965 ◽  
Author(s):  
Harald Burger ◽  
Karl Hensen ◽  
Peter Pickel
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Structure Determination ◽  
Crystal Structure Determination ◽  
Orthorhombic Space Group ◽  
Pyridinium Bromide ◽  
Space Group ◽  
Lattice Constants ◽  
Bromide Ion

AbstractThe compound [(PyH)3Br][AlBr4]2 is formed by melting stoichiometric amounts of AlBr/PyHBr in a ratio of 2:3. It crystallizes in the orthorhombic space group Pbca with lattice constants a = 1365.5(2), b = 1616.0(2), c = 2783.7(3) pm, Z = 8, Dc = 2.21 g/cm3. The structure was solved from 2810 diffractometer measured intensities (Cu -Kα radiation) and refined to Rw (F) = 0.071. The cation shows three pyridinium ions attached via N - H - Br hydrogen bonds to a central bromide ion. The N - Br distances are 321(1), 321(2) and 332(2) pm.

Ternäre Silicide des Lithiums mit Yttrium oder Neodym mit modifizierter U3Si2-Struktur /Ternary Silieides of Lithium with Yttrium or Neodymium in a Modified U3Si2-Type Structure

1979 ◽  
Vol 34 (9) ◽  
pp. 1237-1239 ◽  
Author(s):  
Gunter Steinberg ◽  
Hans-Uwe Schuster
Keyword(s):  
Crystal Structure ◽  
Structure Determination ◽  
Type Structure ◽  
Crystal Structure Determination ◽  
X Ray ◽  
Lattice Constants ◽  
Ray Methods

The two isotypic compounds LiY2Si2 and LiNd2Si2 were prepared and chemically characterized. The crystal structure determination of LiY2Si2 by means of X-ray methods revealed a modified U3Si2-structure. The lattice constants of the tetragonal cells are:LiY2Si2: a = 710.5 pm, c = 414.4 pm.LiNd2Si2 : a = 737.0 pm, c = 424.2 pm.

Chemical State of Nitrogen in Nitrogen-Doped Hydroxyapatite Ceramics with Enhanced Bioactivity

2016 ◽  
Vol 720 ◽  
pp. 215-218
Author(s):  
Ryota Namiki ◽  
Takuya Suyama ◽  
Chihiro Izawa ◽  
Tomoko Ikeda-Fukazawa ◽  
Michiyo Honda ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Chemical State ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lattice Constants ◽  
Hydroxyapatite Ceramics ◽  
N Doping ◽  
Ft Ir ◽  
Temperature Programmed

The chemical state of nitrogen which was induced into crystal structure of hydroxyapatite by nitrogen-doping method (N-doping method) was examined. Determination of lattice constants by powder X-ray diffraction (XRD) showed that the nitrogen species induced by N-doping method substituted the OH- ion in the crystal structure of hydroxyapatite. In addition, Fourier transform infrared spectroscopy (FT-IR) and temperature programmed desorption-mass spectroscopy (TPD-MS) determined that the chemical state of nitrogen induced by N-doping method was N2O.

The crystal structure of eugaAl

1992 ◽  
Vol 50 (2) ◽  
pp. 1452-1453
Author(s):  
H. Brigitte Krause ◽  
Yonglin Qian
Keyword(s):  
Crystal Structure ◽  
Electron Microscope ◽  
Zone Axis ◽  
Unit Cell ◽  
Polycrystalline Specimen ◽  
Lattice Constants

A polycrystalline specimen of nominal formula EuGaAl with unknown crystal structure was investigated by various electron microscope techniques; EDS-, SED-, and CBED data were taken on a Philips 400 electron microscope operated at 100kV, HREM data on a Hitachi 9000 microscope operated at 300kV. The EDS data confirmed the composition for the bulk of the material but, in addition, revealed particles with other fractions of the elements. Only the EuGaAl particles were further investigated. The unit cell was determined to be orthorhombic with a ratio: a/b=0.969(2) , a/c=0.234(2) and b/c=0.234(2). The lattice constants are a=4.54(5)Ȧ, b=4.68Ȧ and c=19.97(20)Ȧ. Based on systematic extinctions for hkl reflections with h+l=2n+l, the unit cell was found to be b-centered. CBED patterns of the [001], [100], and [010] zone axes are shown in Fig. 1. The zone axis patterns are in agreement with the above stated data except for diffused (2m+l,2n+l,0)- reflections, not compatible with the above stated systematic absences. But these occurred only occasionally in conjunction with a complicated noncommensurate superlattice pattern.

Assessment of sensitivity of the efficiency of regional tax spending towards investment attractiveness of the types of economic activity carried out by the residents of advanced development territory

2020 ◽  
pp. 98-110
Author(s):  
Evgeniya Mikhailovna Popova ◽  
Guzel Mukhtarovna Guseinova ◽  
Sergei Borisovich Milov
Keyword(s):  
Economic Activity ◽  
Socioeconomic Development ◽  
Federal District ◽  
Tax Incentives ◽  
Capital Investments ◽  
The Subject ◽  
Investment Process ◽  
The Impact ◽  
Advanced Development

The deficit of subnational budgets and deceleration capital investments in multiple Russian regions increase the relevance of research aimed at improvement of tax incentivizing practice of the regional investment process. The studies focused on determination of the impact of socioeconomic and institutional factors upon the efficiency of investment tax expenses obtained wide circulation within the foreign scientific literature. The subject of this article is the assessment of sensitivity of the efficiency of regional tax expanses towards investment attractiveness of the types of economic activity carried out by the residents of territories of advanced socioeconomic development, created in the subjects of Far Easter Federal District. The scientific novelty and practical values of this research consists in substantiation of the reasonableness of assessment of investment attractiveness of the types of economic activity that are stimulated by tax incentives. Methodology for assessing investment attractiveness is proposed and tested. The conclusion is made that in case of low investment attractiveness of the type of economic activity, which was planned to support by tax incentives, it is required to conduct and additional analysis to avoid unjustified tax expanses.

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

Method development for the determination of textural properties of sugar beet roots

2019 ◽  
pp. 392-400 ◽  
Author(s):  
Gunnar Kleuker ◽  
Christa M. Hoffmann
Keyword(s):  
Sugar Beet ◽  
Compression Test ◽  
Storage Period ◽  
Textural Properties ◽  
Small Sample ◽  
Root Tip ◽  
Flexural Test ◽  
Sample Distribution ◽  
The Impact

The harvest of sugar beet leads to root tip breakage and surface damage through mechanical impacts, which increase storage losses. For the determination of textural properties of sugar beet roots with a texture analyzer a reliable method description is missing. This study aimed to evaluate the impact of washing, soil tare, storage period from washing until measurement, sample distribution and number of roots on puncture and compression measurements. For this purpose, in 2017 comprehensive tests were conducted with sugar beet roots grown in a greenhouse. In a second step these tests were carried out with different Beta varieties from a field trial, and in addition, a flexural test was included. Results show that the storage period after washing and the sample distribution had an influence on the puncture and compression strength. It is suggested to wash the roots by hand before the measurement and to determine the strength no later than 48 h after washing. For reliable and comparable results a radial distribution of measurement points around the widest circumference of the root is recommended for the puncture test. The sample position of the compression test had an influence on the compressive strength and therefore, needs to be clearly defined. For the puncture and the compression test it was possible to achieve stable results with a small sample size, but with increasing heterogeneity of the plant stand a higher number of roots is required. The flexural test showed a high variability and is, therefore, not recommended for the analysis of sugar beet textural properties.

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