scholarly journals SYNTHESIS OF ALLOYS OF THE Sb2Se3-CuCr2Te4 SYSTEM AND PHYSICO-CHEMICAL PROPERTIES

Author(s):  
E. Mamedov ◽  
I. Aliev ◽  
L. Masieva

The interaction in the quasi-ternary system Sb2Se3-CuTe-Cr2Te3 along the Sb2Se3-CuCr2Te4 section was studied by methods of physicochemical analysis: differential thermal (DTA), X-ray phase (XRD), microstructure (MSA), as well as by measuring the density and its microhardness and plotted. The phase diagram of the system is quasi-binary, eutectic type. The composition of the double eutectic formed in the system is 20 mol % CuCr2Te4 and a temperature of 490°C. As a result of the analysis of the microstructure, it was determined that there are single-phase fields based on the original components. It was found that at room temperature, solid solutions based on Sb2Se3 extend to 5 mol % CuCr2Te4, and on the basis of CuCr2Te4 solid solutions reach 13 mol % Sb2Se3.

2020 ◽  
Vol 3 (11(80)) ◽  
pp. 57-62
Author(s):  
F. Sadygov ◽  
N. Mamedova

The chemical interactions in the Bi2Te3-Ho2Te3 system are investigated by methods of physicochemical analysis (DTA, XRD, MSA, microhardness measurements and density determination), a state diagram is constructed. As a result, it was revealed that the system state diagram is a quasi-binary eutectic type. In the Bi2Te3Ho2Te3 system, in a 1: 1 ratio of components, one ternary compound of the HoBiTe3 composition, incongruently melting at 610°C, is formed. According to the results of X-ray phase analysis, it was found that the HoBiTe3 compound crystallizes in the tetragonal system with lattice parameters: a = 19.99; c = 13.82 Å, Z = 3, density ρpikn. = 7.30 g/cm3 ρrent. = 7.35 g/cm3.On the basis of the initial components, regions of solid solutions were found, which on the basis of Bi2Te3 reach 5 mol % Ho2Te3, and on the basis of Ho2Te3 -3 mol % Bi2Te3. Compounds Bi2Te3 and Ho2Te3 form a eutectic with a composition of 20 mol % Ho2Te3 and a temperature of 465°C.


2013 ◽  
Vol 832 ◽  
pp. 589-595 ◽  
Author(s):  
N.A. Edama ◽  
A. Sulaiman ◽  
K.H. Ku Hamid ◽  
M.N. Muhd Rodhi ◽  
Mohibah Musa ◽  
...  

This study analyzed the effects of sulphuric acid (H2SO4) treatment on pysico-chemical properties and morphological changes of clay obtained from Sg. Sayong, Perak. The clay was ground and sieved to <150μm and treated with different concentrations of H2SO4. The treatment was completed by refluxing the clay with different concentration of H2SO4 (1M, 5M and 10M ) at 100 °C for 4 hours and followed by calcination at 500 °C for 1 hour. The physic-chemical properties and morphological changes of the untreated and treated clay were compared using Surface Area Analyser, X-Ray Diffraction (XRD), Field Emission Scanning Electron Micrograph (FESEM), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The results showed that acid treatment of 5M increased the surface area from 25 m2/g to 75 m2/g and the pore volume increased from 0.1518 cc/g to 0.3546 cc/g. The nanopore size of the clay decreased from 24.8 nm to 19.4 nm after treated with acid. This can be explained due to the elimination of the exchangeable cations and generation of microporosity. The results of XRF showed SiO2 increased from 58.34% to 74.52% and Al2O3 reduced from 34.6% to 18.31%. The mineral oxides such as Fe2O3, MgO, CaO, K2O and TiO2 also reduced. This concluded that H2SO4 treatment has led to significant removal of octahedral Al3+, Fe3+ cations and other impurities. In conclusion, this study showed the physico-chemical properties and morphology of Sayong clay were improved once treated with H2SO4 and therefore suggests better supporting material for enzyme immobilization.


2021 ◽  
Vol 14 (5) ◽  
pp. 445-449

Abstract: Spinel ferrites with general formula AB2O4 possess charming magnetic and electrical properties owing to their thermal and chemical steadfastness. Spinel zinc ferrite (ZnFe2O4) nanoparticles have attracted massive attention due to their unusual amalgamation of properties, especially magnetic properties, where these properties are equipped as suitable candidates in the field of electronics. Here, a simple self-combustion technique is made with the assistance of albumen to synthesize nanocrystalline zinc ferrite (ZnFe2O4) particles. The egg white (albumen) that is used in the synthesis process plays the fuel role in the process of combustion. The results of the powder X-ray diffraction (PXRD) and Fourier Transform Infrared Spectroscopy (FTIR) suggested that the synthesized nanoparticles are of single phase and show spinel structure. The photoluminescence studies reported a doublet peak at around 360-380 nm. The functional groups present in the synthesized nanoparticles were revealed from FTIR data. EDX findings give an account of the percentage composition of the elements Fe, Zn and O present in the synthesized sample. High-resolution Scanning Microscope (HRSEM) reveals the agglomerated coalescence nature of ferrite nanoparticles. Keywords: Ferrite, PXRD, FTIR, HRSEM, EDX Albumen.


2021 ◽  
Vol 7 (5(59)) ◽  
pp. 28-31
Author(s):  
ТЕЙМУР МАМЕД ИЛЬЯСЛИ ◽  
ДУНИЯ ТАЛЕХ ГАСАНОВА ◽  
ИМИР ИЛЬЯС АЛИЕВ

To determine the area of glass formation in the system As2S3-ErS were synthesized alloys in the range of concentrations 0-30 mol. % ErS. The methods of physico-chemical analysis of differential-thermal (DTA), X-ray phase (RFA), microstructural (MCA) analyzes, as well as the measurement of microhardness and density determined the area of the glass and studied them physicо-chemical propertes. It is established that in the system As2S3-ErS on the basis of As2S3 during slow cooling the area of the glass reaches 17 mol. % ErS. Alloys in the concentration range 20-30 mol. % ErS are glass-crystalline. In the system at room temperature solid solutions on the basis of As2S3 are distributed up to 2.5 mol.% ErS, and on the basis of solid solutions ErS are practically not installed.


2005 ◽  
Vol 492-493 ◽  
pp. 331-334
Author(s):  
Jin Seok Lee ◽  
Sung Churl Choi

Well-crystallized and nano-sized indium tin oxide (ITO) powders were prepared by a solvothermal process from a mixed solution consisting of indium nitrate and tin chloride. The characteristics of the solvothermally synthesized ITO powders were studied to investigate the contribution of the processing variables on the physico-chemical properties of powders. The results of this study show that the nano-sized blue ITO powders with a single phase could be directly obtained by changing the medium from water to organic solvent.


1990 ◽  
Vol 22 (1-2) ◽  
pp. 1-16 ◽  
Author(s):  
P. G. Rouxhet ◽  
N. Mozes

The thermodynamic approach of adhesion and DLVO theory are complementary to predict initial bacterial adhesion; the interplay between short- and long-range forces, respectively, may be due to surface roughness. Due to the influence of electrical double layer interactions, adhesion can be promoted by treatments leading to modification of the cell or support surface properties. Adhesion is influenced by cell-cell interactions, by the cpresence of polymer molecules on the surface and by the composition of the medium. X-ray photoelectron spectroscopy can be applied to determine the elemental composition of the surface of microorganisms; some information on the chemical functions can also be obtained. The surface composition is related to physico-chemical properties which play a determining role in adhesion and flocculation, in particular the hydrophobicity and the zeta potential.


2019 ◽  
Vol 9 (13) ◽  
pp. 2598 ◽  
Author(s):  
M. J. Hernández-Rodríguez ◽  
R. Santana Rodríguez ◽  
R. Darias ◽  
O. González Díaz ◽  
J. M. Pérez Luzardo ◽  
...  

In this study, mortar specimens were prepared with a cement:sand:water ratio of 1:3:0.5, in accordance with standard EN196-1. Portland CEM I 52.5 R grey (G) and white (W) cements were used, together with normalised sand and distilled water. Different amounts of TiO2 photocatalyst were incorporated in the preparation of the mortar samples. The effect of the addition of TiO2 was studied on mechanical properties of the mortar and cement including compressive and flexural strength, consistency (the flow table test), setting time and carbonation. Characterization techniques, including thermogravimetry, mercury porosimetry and X-ray diffraction spectroscopy (XRD), were applied to study the physico-chemical properties of the mortars. It was shown that adding the photocatalyst to the mortar had no negative effect on its properties and could be used to accelerate the setting process. Specimen photoactivity with the incorporated photocatalyst was tested for NOx oxidation in different conditions of humidity (0% RH and 65% RH) and illumination (Vis or Vis/UV), with the results showing an important activity even under Vis radiation.


1988 ◽  
Vol 43 (5) ◽  
pp. 611-615 ◽  
Author(s):  
T. Sogo ◽  
J. Romero ◽  
A. Sousa ◽  
A. de Blas ◽  
M. L. Durán ◽  
...  

Abstract The electrochemical synthesis and physico-chemical properties of neutral zinc(II) complexes of bidentate Schiff bases derived from salicylaldehydes are presented together with the X-ray structure of bis[N-(4-methylphenyl)salicylaldiminato]zinc(II). The crystal is monoclinic, a = 21.877(3), b = 8.801(2), c = 12.027(5) Å, β = 96.55(3)°, space group C2/c. The complex is a monomer, and the zinc atom is tetrahedrally coordinated.


2021 ◽  
Vol 16 ◽  
pp. 1-11
Author(s):  
Nor Farah Hida Othman ◽  
Noor Syafiqah Habdul Latif ◽  
Sheikh Ahmad Izzadin Sheikh Mohd Ghazali ◽  
Erna Normaya Abdullah ◽  
Nur Nadia Dzulkifli

In industrial sectors, pickling and acid cleaning are mutual processes where acid solutions, such as hydrochloric acid (HCl) and sulfuric acid (H2SO4), are used to eliminate the corrosion products yielded on metal surfaces; thus, improving the performance of the machineries. However, the usage of the acid could lead to another metal deterioration. Dithiocarbamate inhibitor is defined as an organic compound that has good corrosion inhibition properties that can work as an inhibitor in an acid environment. Dithiocarbamate (DTC) assists by reducing acid reactiveness which prohibits metal dissolution in the acid. In this study, the Ni(II) N-butylmethyldithiocarbamate (Ni[BuMedtc]2) complex was synthesised by using an in-situ method and characterised by elemental analyser, attenuated total reflection Fourier transform infrared (ATR-FTIR), ultraviolet-visible (UV-Vis) spectroscopy and X-ray crystallographic study, and the chemical properties of the Ni[BuMedtc]2 complex was successfully calculated by the Discrete Fourier Transform (DFT) approach. The experimental results which were obtained through the weight-loss analysis method in two different acids – 1 M HCl and 1 M H2SO4 – indicated that the inhibition efficiency increased as the inhibitor concentration increased. The outcome showed that the Ni[BuMedtc]2 performed better as an inhibitor in 1 M HCl as compared to in1 M H2SO4 to protect the metal exterior because H2SO4 is more corrosive due to the excessive presence of H+.


2020 ◽  
pp. 357-364
Author(s):  
Mikhail Yur'yevich Belash ◽  
Irina Vladimirovna Korol'kova ◽  
Yevgeniya Vladimirovna Veprikova ◽  
Galina Nikolayevna Bondarenko ◽  
Irina Vladimirovna Korol'kova ◽  
...  

The physicochemical properties of the composite material obtained by sequentially impregnating the substrate from aspen bark with water solutions of KH2PO4 and CaCl2 under certain conditions were studied. Using the method of X-ray phase analysis, it was found that the main products of the interaction of KH2PO4 and CaCl2, which flows from the aspen bark on the substrate surface, are CaHPO4 and KCl. In this case, calcium chloride is present in the obtained composite material in the form of a complex compound CaCl2·Ca(OH)2·H2O. Using IR-spectral analysis, it was revealed that there is no interaction between the functional groups of the aspen bark substrate and mineral compounds during the preparation of the composite material. Based on thermal analysis data, the catalytic effect of the mineral components that make up the developed composite material on the decomposition of hemicellulose, cellulose and lignin that make up the substrate from aspen bark is revealed. It was found that the composite material modified with CaHPO4 is characterized by increased water resistance and after treatment with water at room temperature for 24 hours, 9.85% of phosphates are removed from it (from their initial content). This allows one to use the resulting composite material based on aspen bark as a delayed-action fertilizer.


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