scholarly journals Processes of structure and phase formation of aerated concrete of non-autoclave hardening containing ferrosilicon as a gasifier

2021 ◽  
pp. 45-50
Author(s):  
A.O. Musina ◽  
◽  
O.O. Sihunov ◽  
O.P. Ryzhova ◽  
O.S. Sverdlikovska ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Phase Composition ◽  
Porous Structure ◽  
Dicalcium Silicate ◽  
X Ray ◽  
Calcium Hydrosilicates ◽  
Aerated Concrete ◽  
Differential Thermal Analysis Analysis ◽  
Ray Patterns

The paper deals with the structure and phase composition of non-autoclave aerated concrete with a density of 600–800 kg m–3 using ferrosilicon as a gasifier. The conditions of formation of porous structure of aerated concrete and preparation of calcium hydrosilicates were considered. Phase composition of the samples was investigated by means of X-ray phase analysis and differential thermal analysis. Analysis of X-ray patterns showed that the test samples contained tobermorite 11.3 Å (5CaO6SiO25.5H2O), xonotlite (6CaO6SiO2H2O) and -dicalcium silicate hydrate (2CaOSiO2H2O) as a binder. It was established that there is an increase in the content of hydrosilicate phases with an increase in the content of gasifier in the vast majority of cases. The obtained data were confirmed by the results of differential thermal analysis.

scholarly journals The devitrification of PbO-B2O3-ZnO glass doped with Li2O

2000 ◽  
Vol 65 (12) ◽  
pp. 891-898 ◽  
Author(s):  
Vladimir Zivanovic ◽  
Nikola Blagojevic ◽  
Snezana Grujic ◽  
Ljiljana Karanovic ◽  
Branislava Bozovic
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Phase Composition ◽  
Powder Diffraction ◽  
Crystalline Phase ◽  
Crystallization Behavior ◽  
X Ray ◽  
Crystallization Ability ◽  
Lower Temperature ◽  
Xrpd Analysis

In this paper the effect of the addition of Li2O on the crystallization behavior of PbO-B2O3-ZnO glass was investigated by the differential thermal analysis (DTA) and X-ray powder diffraction (XRPD) methods. The crystallization ability, as well as the crystalline phases which develop during devitrification of the glass were examined. The results of DTA and XRPD analysis showed that the addition of Li2O varies the sequence of the crystallization as well as the phase composition of the crystalline phase. The glasses with Li2O crystallize at a lower temperature (360?C) with 4Li2O.4ZnO.3B2O3 as the major crystalline phase. The base PbO-B2O3-ZnO glass crystallizes at 480?C with PbO.2ZnO.B2O2 as the major crystalline phase.

scholarly journals LaCoO3 perovskite-type catalysts in syngas conversion

2020 ◽  
Vol 18 (1) ◽  
pp. 482-487
Author(s):  
Gulim Danebaevna Jetpisbayeva ◽  
Eugene Vladimirovich Dokuchits ◽  
Angelina Nikolaevna Tafilevich ◽  
Tatyana Petrovna Minyukova ◽  
Bakytgul Kabykenovna Massalimova ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Phase Composition ◽  
Coal Sample ◽  
X Ray Diffraction ◽  
Subsequent Reduction ◽  
X Ray ◽  
Syngas Conversion ◽  
Liquid Products ◽  
Perovskite Type

AbstractLaCoO3 samples were obtained by the hydrothermal and citrate methods. The dynamics of the phase transformations of the initial hydroxo compounds into the oxide state and the subsequent reduction in a hydrogen-containing mixture were studied by the differential thermal analysis and X-ray diffraction methods. The results of the catalytic tests in the syngas conversion showed that the path of conversion depends on the phase composition of the catalyst in the oxide state. In contrast to the standard CoAl sample, alcohols prevail in the liquid products formed on LaCoO3 catalysts.

scholarly journals Synthesis and study of a novel 9P-type mixed layered tetradymite-like GeBi4Te4 compound in the Ge-Te-Bi system

2021 ◽  
Vol 22 (3) ◽  
pp. 401-406
Author(s):  
F.R. Aliyev
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Phase Composition ◽  
Lattice Parameter ◽  
The Novel ◽  
Layered Chalcogenides ◽  
X Ray ◽  
Parameter Values ◽  
Scanning Electron

Taking as a base structural properties of the tetradymite-like layered chalcogenide compounds, a novel ternary GeBi4Te4 phase was predicted and synthesized. The polycrystal of this compound was synthesized and its single-crystal was grown by the vertical Brigman-Stokbarger method. The phase composition of obtained samples was analyzed by differential thermal analysis (DTA), X-ray powder diffraction (XRD), and scanning electron microscope (SEM). It was determined that the novel phase melts peritectially at 538 °C and has the following lattice parameter values in a hexagonal configuration: a=4,4071(6)Å, c=17,384(2)Å (sp. gr P3m1). This crystal structure is considered a derivative of tetradymite-like layered chalcogenides and consists of alternating Bi bilayers and GeBi2Te4 septuple packets.

PENINGKATAN LAJU DISOLUSI ACYCLOVIR DENGAN METODE SISTEM DISPERSI PADAT MENGGUNAKAN POLOXAMER 188

2016 ◽  
Vol 5 (1) ◽  
pp. 6
Author(s):  
Budi Setiawan ◽  
Erizal Zaini ◽  
Salman Umar
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Fourier Transform ◽  
Differential Thermal Analysis ◽  
Fourier Transform Infrared ◽  
X Ray Diffraction ◽  
Poloxamer 188 ◽  
X Ray ◽  
Scanning Electron

Sebuah penelitian tentang sistem dispersi padat dari asiklovir dengan poloxamer 188 telah dilakukan formulasi dengan pencampuran secara fisika dengan rasio 1 : 1, 1 : 3, 1 : 5 dan dispersi padat 1 : 1, 1 : 3, 1 : 5 dan penggilingan 1:1 sebagai pembanding. Dispersi padat dibuat menggunakan metode pencairan (fusi), yang digabung dengan poloxamer 188 pada hotplate kemudian asiklovir dimasukkan ke dalam hasil poloxamer 188 lalu di kocok hingga membentuk masa homogen. Semua formula yang terbentuk termasuk asiklovir poloxamer 188 murni dianalisis karakterisasinya dengan Differential Thermal Analysis (DTA), X-ray Diffraction, Scanning Electron Microscopy (SEM), dan Fourier Transform Infrared (FTIR), kemudian pengambilan dilakukan  (penentuan kadar) mengunakan spektrofotometer UV pada panjang gelombang 257,08 nm dan uji laju disolusi dengan aquadest bebas CO2 menggunakan metode dayung. Hasil pengambilan  (penentuan kadar) menunjukkan bahwa semua formula memenuhi persyaratan farmakope Amerika edisi 30 dan farmakope Indonesia edisi 4 yaitu 95-110%. Sedangkan hasil uji laju disolusi untuk campuran fisik 1: 1, dan dispersi padat 1: 1, dan penggilingan 1: 1 menunjukkan peningkatan yang nyata dibandingkan asiklovir murni. Hal ini juga dapat dilihat dari hasil perhitungan statistik  menggunakan analisis varian satu arah  SPSS 17.

scholarly journals The Potential for Natural Stones from Northeastern Brazil to Be Used in Civil Construction

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 440
Author(s):  
Fabiana Pereira da Costa ◽  
Jucielle Veras Fernandes ◽  
Luiz Ronaldo Lisboa de Melo ◽  
Alisson Mendes Rodrigues ◽  
Romualdo Rodrigues Menezes ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Chemical Resistance ◽  
Mechanical Analysis ◽  
Northeastern Brazil ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Agents ◽  
Natural Stones

Natural stones (limestones, granites, and marble) from mines located in northeastern Brazil were investigated to discover their potential for use in civil construction. The natural stones were characterized by chemical analysis, X-ray diffraction, differential thermal analysis, and optical microscopy. The physical-mechanical properties (apparent density, porosity, water absorption, compressive and flexural strength, impact, and abrasion) and chemical resistance properties were also evaluated. The results of the physical-mechanical analysis indicated that the natural stones investigated have the potential to be used in different environments (interior, exterior), taking into account factors such as people’s circulation and exposure to chemical agents.

scholarly journals X-Ray Investigations of the Low-Temperature Phases of the Organic Metals α- and β-(BEDT-TTF)2I3

1986 ◽  
Vol 41 (11) ◽  
pp. 1319-1324 ◽  
Author(s):  
H. Endres ◽  
H. J. Keller ◽  
R. Swietlik ◽  
D. Schweitzer ◽  
K. Angermund ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Room Temperature ◽  
Unit Cell Volume ◽  
Unit Cell ◽  
Slight Variation ◽  
X Ray ◽  
Organic Metals ◽  
Β Phase ◽  
Α Phase

The structure of single crystals of the organic metals α- and β-(BEDT-TTF)2I3* was determined at 100 K, well below the phase transitions indicated by resistivity and thermopower measurements as well as by differential thermal analysis. In the α-phase no unusual change of the room temperature unit cell but a slight variation in the triiodide network and especially a more pronounced dimerization in one of the two donor stacks have been found. The β-phase develops a superstructure with a unit cell volume three times as large as that at room temperature and with pronounced distortions of the I3--ions.

The Roman Ceramics of Salobrena (Granada-Spain) and their Raw Materials

1992 ◽  
Vol 267 ◽  
Author(s):  
Ana M De Andres ◽  
Isabel MuÑOZ
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Raw Materials ◽  
Third Century ◽  
Western Coast ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Third ◽  
Good Number ◽  
Scanning Electron

ABSTRACTNineteen roman ceramic sherds found near Salobreña (Granada, Spain), in the western coast of the Mediterranean Sea, as well as different ceramic clays from the surroundingsare studied. Both clays and ceramic sherds are characterizad by X-ray diffraction and spectrometry, differential thermal analysis, and scanning electron and optical microscopies. A good number of the ceramic pieces, among which some “Terrae Sigillatae”, have a composition similar to that of the local clays and, thus, have been probably manufactured at Salobreña. Only a few of them have a foreign origin. For most of them, the firing temperature was about 800-850 °C, although some have been produced at 900-1000 °C, and some others at 1000-1100 °C. It is concluded that Salobreña appearsto have been an important settlement just in the third century of the Christian era.

scholarly journals Influence of the Al content on the phase transformations in Cu-Al-Ag alloys

2003 ◽  
Vol 28 (1) ◽  
pp. 33-38 ◽  
Author(s):  
A. T. Adorno ◽  
A. V. Benedetti ◽  
R. A. G. da Silva ◽  
M. Blanco
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Transition Temperature ◽  
Phase Transformations ◽  
Decomposition Reaction ◽  
Phase Decomposition ◽  
Stability Range ◽  
X Ray ◽  
Al Content ◽  
The Stability

The influence of the Al content on the phase transformations in Cu-Al-Ag alloys was studied by classical differential thermal analysis (DTA), optical microscopy (OM) and X-ray diffractometry (XRD). The results indicated that the increase in the Al content and the presence of Ag decrease the rate of the <FONT FACE=Symbol>b</font>1 phase decomposition reaction and contribute for the raise of this transition temperature, thus decreasing the stability range of the perlitic phase resulted from the b1 decomposition reaction.

scholarly journals Silica-Kaolin Mix Effect on Evaporative Pattern Castings Surface Roughness

2016 ◽  
Vol 16 (3) ◽  
pp. 83-88 ◽  
Author(s):  
B.V. Omidiji ◽  
R.H. Khan ◽  
M.S. Abolarin
Keyword(s):  
Thermal Analysis ◽  
Surface Roughness ◽  
Differential Thermal Analysis ◽  
Ratio Method ◽  
Gating System ◽  
X Ray Diffraction ◽  
Pouring Temperature ◽  
Material Loss ◽  
Refractory Coating ◽  
X Ray

Abstract The influence of the refractory coating which is a mixture of silica flour and kaolin on the surface roughness of the plate castings produced using evaporative patterns had been considered in this work. The kaolin was used as a binder and ratio method was employed to form basis for the factorial design of experiment which led to nine runs of experiments. Methyl alcohol at 99% concentration was used as the carrier for the transfer of the coating to the surface of the patterns. Pouring temperature was observed as a process parameter alongside the mix ratios of the coating. Attempts were made to characterize the refractory coating by using two methods; differential thermal analysis (DTA) and X-ray diffraction. Attempt was also made to characterize the casting material. Gating system design was done for the plate casting to determine the correct proportions of the gating parameters in order to construct the gating system properly to avoid turbulence during pouring of liquid metal. A digital profilometer was used to take the measurements of the surface roughness. It was observed that the mix ratio 90% silica flour-10% kaolin produced the lowest value of the surface roughness of the plate castings and had the lowest material loss in the DTA test. The pouring temperature of 650°C produced best casting.

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