scholarly journals Research of the dynamics of condensed product deposition

2014 ◽  
pp. 109
Author(s):  
S. V. Tsaplin ◽  
S. A. Bolychev
Keyword(s):  
Condensed Product

Apatite-staffelite ore flotation efficiency improvement using two-stage slurry thickening

2022 ◽  
pp. 121-131
Author(s):  
Valery Morozov ◽  
Polivanskaya Valeriya
Keyword(s):  
Caustic Soda ◽  
Liquid Glass ◽  
Efficiency Improvement ◽  
Selective Flocculation ◽  
Two Stage ◽  
Flotation Process ◽  
Apatite Concentrate ◽  
P2o5 Content ◽  
Condensed Product ◽  
Mode A

The studies were performed suggesting that the cause of P2O5 losses during apatite-staffelite ores (ASO) treatment are due to non-selective flocculation of fine classes during flotation. When using strong flocculants, special preparation of condensed slurries is necessary, ensuring their deflocculation before the flotation process. A scheme and mode of preparation of fine classes for the flotation process have been developed, including thickening of the classification overflows using strong anionic flocculants and deflocculation of the thickened product before the flotation process with reagents-dispersants used in the basic flotation mode. A mode of preparation of slimes of ASO ores for flotation is proposed, including thickening of the discharge of the classification operation using the anionic flocculant “Praestol-2540”, conditioning of the condensed product with additions of liquid glass and caustic soda in a ratio of 1 : 1, dilution and re-thickening of deflocculated slimes, consolidation and flotation thickened sludge and sand. The big laboratory tests have shown that the application of the developed regime provides a total increase in the extraction of P2O5 from ore from 70,1 to 71,5 % with an increase in the P2O5 content in apatite concentrate from 37,1 to 37,8 %, which makes the developed technology promising for processing refractory ASO at Kovdorsky GOK.

scholarly journals Thermodynamic simulation of oxidation process of the Moss-Mo3Si hypoeutectic alloy, doped with scandium or neodymium

2019 ◽  
Vol 57 (2) ◽  
pp. 90-100
Author(s):  
Alexey V. Larionov ◽  
◽  
Ludmila Y. Udoeva ◽  
Vladimir M. Chumarev ◽  
◽  
...  
Keyword(s):  
Oxidation Process ◽  
Thermodynamic Simulation ◽  
Oxidation Products ◽  
Hypoeutectic Alloy ◽  
Protective Film ◽  
Chemical Transformations ◽  
Reaction Products ◽  
Moist Air ◽  
Condensed Product ◽  
Hsc Chemistry

In order to study the effect of yttrium additives on the oxidation of molybdenum silicide alloys, thermodynamic modeling of the interaction in Mo-Mo3Si-Sc5Si3 и Mo-Mo3Si-NdSi systems with dry and moist air was performed in the temperature range 25-2000 °C. The calculations were performed using the HSC Chemistry 6.12 software, into the database of which the calculated missing thermochemical characteristics silicates, molybdates of scandium and neodymium were entered. Based on the obtained dependences of the composition of phases on temperature and charge of the oxidant (air or vapor-air mixture), the sequence of phase formation was determined and the compositions of oxidation products were estimated. It is shown that, under equilibrium conditions, the oxidation process with dry and moist air proceeds almost equally, since the interaction of the components of the alloy with oxygen is thermodynamically preferable than with water vapor. According to the obtained thermodynamic models, the oxidation process of the Mo-5Si-3(Sc, Nd) (wt.%) alloys involves a sequence of the following chemical transformations: at the beginning Mo and Sc (Nd) silicides oxidize forming Sc2O3 ( Nd2O3), SiO2 and elemental Mo, then molybdenum is oxidized to MoO2 and Sc2O3 or Nd2O3 interacts with SiO2 with the formation of appropriate silicates Sc2Si2O7 или Nd2Si2O7. As a result of the complete oxidation of the alloy, MoO3 and Sc2(MoO4)3 or Nd2Mo4O15 are added to the condensed product, and molybdenum oxide (MoO3)n vapor appears in the gas phase. In addition, the formation of Nd2Mo2O7 and Nd2 (MoO4)3 is possible. During the oxidation of the Mo-5Si-3Nd alloy at T> 1700 oC, Nd(OH)3 can be formed in the condensed reaction products. According to the results of complete thermodynamic analysis, the formation of silicates and molybdates of scandium and neodymium can promote to the formation of a protective film on the surface of the alloys, which limits the diffusion of oxygen in them, and as a result, the oxidation resistance of alloys should increase.

Effect of Molecular Structure of Polyols with Different Molecular Characteristics on Synthesis of Boron Carbide Powder

2013 ◽  
Vol 534 ◽  
pp. 61-65 ◽  
Author(s):  
Masaki Kakiage ◽  
Naoki Tahara ◽  
Yusuke Tominaga ◽  
Satomi Yanagidani ◽  
Ikuo Yanase ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Thermal Decomposition ◽  
Boron Carbide ◽  
Carbothermal Reduction ◽  
Poly Vinyl Alcohol ◽  
Molecular Characteristics ◽  
Carbide Powder ◽  
Excess Carbon ◽  
Condensed Product ◽  
Crystalline Boron

Crystalline boron carbide (B4C) powder was synthesized by the carbothermal reduction of condensed products formed from boric acid (H3BO3) and polyols with different molecular characteristics, i.e., glycerin, mannitol, and poly (vinyl alcohol) (PVA). The effect of the molecular structure of the polyol on the thermal decomposition conditions and the obtained morphology of the B4C powder was discussed in this study. The thermal decomposition in air of each condensed product was performed before the carbothermal reduction in order to eliminate the excess carbon, where the decomposition conditions varied with the type of polyol. Crystalline B4C powder with less residual free carbon was synthesized from the thermally decomposed products by heating at 1250 °C for 5 h in an Ar flow. The thermal decomposition conditions and the particle size of the obtained B4C powder reflected the molecular characteristics of the polyols.

Condensation products of pyrrole and hexane-2,5-dione

1968 ◽  
Vol 21 (8) ◽  
pp. 2053 ◽  
Author(s):  
LK Dalton ◽  
T Teitei
Keyword(s):  
Acetic Acid ◽  
Zinc Acetate ◽  
Glacial Acetic Acid ◽  
Condensation Products ◽  
Condensed Product

Pyrrole and hexane-2,b-dione react in glacial acetic acid containing zinc acetate to give 4,7-dimethylindole, 5,8-dimethylindolizine, 1,4,6,8-tetramethyl-carbazole and a more highly condensed product which has been assigned the structure 1,4-bis(4,7-dimethylindol-2-yl)-1,4,5,8-ethyl-l,2,3,4-tetrahydrocarbazole.

scholarly journals Selective labelling of arginine residues engaged in binding sulfatedglycosaminoglycans

2019 ◽  
Author(s):  
Thao P. Bui ◽  
Yong Li ◽  
Quentin M. Nunes ◽  
Mark C. Wilkinson ◽  
David G. Fernig
Keyword(s):  
Affinity Column ◽  
Side Chains ◽  
Heparin Binding ◽  
Reaction Products ◽  
Selective Labelling ◽  
Carboxylate Groups ◽  
Condensed Product ◽  
Ionic Bonds ◽  
Arginine Residues ◽  
Anionic Groups

IAbstractThe activities of hundreds of proteins in the extracellular space are regulated by binding to the glycosaminoglycan heparan sulfate (HS). These interactions are driven by ionic bonds between sulfate and carboxylate groups on the polysaccharide and the side chains of basic residues in the protein. Here we develop a method to selectively label the guanidino side chains of arginine residues in proteins that engage the anionic groups in the sugar. The protein is bound to heparin (a common experimental proxy for HS) on an affinity column. Arginine side chains that are exposed to solvent, and thus involved in binding, are protected by reaction with the dicarbonyl phenylgyoxal (PGO). Elution of the bound proteins then exposes arginine side chains that had directly engaged with anionic groups on the polysaccharide. These are reacted with hydroxyl-phenylglyoxal (HPG). PGO was found to generate three products: a 1:1 product, the 1:1 water condensed product and a 2:1 PGO:arginine product. These three reaction products and that of HPG had distinct masses. Scripts were written to analyse the mass spectra and so identify HPG labelled arginine residues. Proof of principle was acquired on model peptides. The method was then applied to the identification of heparin binding arginine residues in fibroblast growth factors (FGF) 1 and 2. The data demonstrate that four out of eleven arginine residues on FGF2 and five out of six arginine residues of FGF1 engage heparin. Our approach provides a rapid and reliable means to identify arginines involved in functional complexes such as those of proteins with heparin

Tetrahydrocannabinether, A Novel Condensed Product of Δ9-THC from Cannabis sativa

2021 ◽  
Author(s):  
Mudasir A. Tantry ◽  
Shahista Bashir ◽  
Shameen A. Shameem ◽  
Shoaib A. Dar
Keyword(s):  
Cannabis Sativa ◽  
Condensed Product

scholarly journals Nucleation and Condensation of Magnesium Vapor in Argon Carrier

Metals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1441
Author(s):  
Jibiao Han ◽  
Daxue Fu ◽  
Junhua Guo ◽  
Zonghui Ji ◽  
Zhihe Dou ◽  
...  
Keyword(s):  
Heat Source ◽  
Flow Rate ◽  
Vapor Condensation ◽  
Condensation Temperature ◽  
Atomic Collisions ◽  
Condensation Zone ◽  
Source Temperature ◽  
Heat Source Temperature ◽  
Vapor Partial Pressure ◽  
Condensed Product

The nucleation and condensation of Magnesium (Mg) vapor carried by argon gas (Ar) were examined. The condensation of Mg vapor at a heat source temperature of 1273–1473 K and Ar flow rate of 0.1–0.4 m3/h was analyzed. The result indicated that the condensation temperature is affected by the heat source temperature and Ar flow rate, and the condensation temperature of Mg vapor was 1013.3 K at a heat source temperature of 1473 K and Ar flow rate of 0.2 m3/h. The effects of Mg vapor partial pressure and temperature of the condensation zone on the nucleation and condensation of Mg vapor carried by Ar were calculated and analyzed in terms of atomic collisions and critical nucleation radius. Increased vapor oversaturation and decreased condensation temperature were favorable for liquid nucleation growth. The Mg condensation products in Ar flow rate of 0.2 m3/h at a heat source temperature of 1473 K were analyzed by XRD, SEM, and EDS, which indicated that the condensed product was of high purity and not easily oxidized in Ar flow. In this paper, the quality of Mg vapor condensation was controlled, which provided the theoretical and experimental basis for a continuous Mg production process.

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