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Articles 1 - 30 of 179
Full-Text Articles in Engineering
Synthesis Of Acetylene Diols With The Participation Of The Bu4noh/Dmso/H2o Catalytic Systems, Muyassar K. Salieva, Odiljon E. Ziyadullayev, Guzal K. Otamukhamedova, Rifkat F. Talipov, Lochin K. Ablakulov
Synthesis Of Acetylene Diols With The Participation Of The Bu4noh/Dmso/H2o Catalytic Systems, Muyassar K. Salieva, Odiljon E. Ziyadullayev, Guzal K. Otamukhamedova, Rifkat F. Talipov, Lochin K. Ablakulov
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of this work in this study, acetylene alcohols containing heteroatomic substituents in their molecular composition- 2-(-thiophen-2-yl)but-3-yn-2-ol, 2-(3-methylthiophen-2-yl)but-3-yn-2-ol, 2-(furan-2-yl)but-3yn-2-ol, 2-(pyridin-4-yl)but-3-yn-2-ol, 2-(5-chlorothiophen-2-yl)but-3-yn-2-ol, 2-(5-bromothiophen-2yl)but-3-yn-2-ol acetylene diols were synthesized based on the reaction with acetone in a dimethyl sulfoxide solvent in the presence of the Bu4NOH/DMSO/H2O catalytic system. The influence of the molar ratio of starting materials, reaction duration, temperature, nature of the catalyst and solvents on the product yield was systematically studied. The composition, purity and structure of the new generation of synthesized acetylenediols have been confirmed by modern physicochemical methods. The mechanism of the reaction process …
Synthesis Of High Molecular Mass Resins Based On Furfuryl Alcohol, Boysayid U. Sayidov, Latif E. Jumanov, Muzaffar G. Alimukhamedov, Sherali A. Umarov, Farhod A. Magrupov
Synthesis Of High Molecular Mass Resins Based On Furfuryl Alcohol, Boysayid U. Sayidov, Latif E. Jumanov, Muzaffar G. Alimukhamedov, Sherali A. Umarov, Farhod A. Magrupov
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of the work is to study the process of synthesis of furfuryl oligomers with high molecular weight at various ratios of furfuryl alcohol and hydroxyl-containing polyether polyol. The influence of the process method on the yield of high-molecular furfuryl oligomer is shown - with a one-step synthesis method with an increase in the amount of furfuryl alcohol from 20 to 50 moles per 1 mole of polyether polyol, the yield of the final product decreases from 75% to 56%, apparently due to high exothermic effects, causing gelation systems. In contrast to the one-time introduction of the catalyst, its …
Synthesis And Technology Of Vinyl Esters Of Aromatic Carboxylic Acids Based On Vinyl Acetate, Askar B. Parmanov, Suvonkul E. Nurmanov, Saida S. Abdurakhmanova, Sarvinoz I. Tirkasheva, Begzod F. Adashev
Synthesis And Technology Of Vinyl Esters Of Aromatic Carboxylic Acids Based On Vinyl Acetate, Askar B. Parmanov, Suvonkul E. Nurmanov, Saida S. Abdurakhmanova, Sarvinoz I. Tirkasheva, Begzod F. Adashev
CHEMISTRY AND CHEMICAL ENGINEERING
In this work the vinylation reactions of aromatic carboxylic acids with vinyl acetate, which contain various substituents, in the presence of 2-chloro-4,6-dimethoxy-1,3,5-triazine were studied for the first time. The influence of the nature of the starting materials, temperature, reaction duration, solvent and reagents - zinc triflate (Zn(OTf)2, 3,3-diphenylbinaphthol (3,3'-Ph2BINOL-2Li), tertiary potassium butylate (KOtrBu), butyllithium (BuLi) for the synthesis of vinyl esters. The synthesis of vinyl esters of aromatic carboxylic acids was carried out: benzoiс, 2-phenylacetic, 4-methylbenzoic, 4-methoxybenzoic, 3,4-dimethoxybenzoic, 2-brombenzoic, 4-brombenzoic, 4-fluorobenzoic, 3-nitrobenzoic, 4-nitrobenzoic, 4-tertiary butylbenzoic, 2-chlorobenzoic, 4-chlorobenzoic, 3-hydroxybenzoic and 4-hydroxybenzoic acids has been studied. …
Synthesis Of Internal Acetylene Alcohols Based On The Sonogashira Reaction Of Terminal Acetylene Alcohols And Benzolchloride, Guzal K. Otamukhamedova, Odiljon E. Ziyadullayev, Abduvahob Ikramov, Sarvinoz I. Tirkasheva
Synthesis Of Internal Acetylene Alcohols Based On The Sonogashira Reaction Of Terminal Acetylene Alcohols And Benzolchloride, Guzal K. Otamukhamedova, Odiljon E. Ziyadullayev, Abduvahob Ikramov, Sarvinoz I. Tirkasheva
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of the study is to develop a new catalytic system for the synthesis of internal acetylene alcohols from the Sonogastric coupling reaction of terminal acetylene alcohols and benzolchloride. For the first time in this work, internal acetylene alcohols have been synthesized based on reactions of some terminal acetylene alcohols – 3,4-dimethylpentin-1-ol-3, 3,4,4-trimethylpentin-1-ol-3, 1-ethynylcyclohexanol-1, 2-ethynyladamantanol-2, 2-phenylbutin-3-ol-2, 2-(naphthyl-2)butyn-3-ol-2, 2-(furanyl-2)butyn-3-ol-2 and 2-(pyridinyl-4)butyn-3-ol-2 with chloridebenzene. In order to achieve high product productivity in the Sonogashira reaction, alternative conditions have been identified by studying the molar ratios, spatial structure, induction effects of substituents, solvent and catalyst nature, as well as temperature, reaction duration …
Study Of The Influence Of B2o3 Oxide On The Physical And Technical Properties Of Ground Enamel Obtained Based On Local Raw Material Components, Shoxrux B. Naimov, Mastura Kh. Aripova
Study Of The Influence Of B2o3 Oxide On The Physical And Technical Properties Of Ground Enamel Obtained Based On Local Raw Material Components, Shoxrux B. Naimov, Mastura Kh. Aripova
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of the study was to obtain ground enamel based on local raw materials and to study the effect of boron oxide. The selection of local raw materials for producing ground enamel showed that the resulting glass compositions are in the SiO2–Al2O3–Na2O–K2O–CaO–B2O3 system. To adjust the properties, additives of nickel oxide and cobalt oxide were used. The properties of the developed compositions of primer enamels meet the requirements of GOST 24405-80. It has been determined that the addition of boron and an increase in its amount …
Formation Of Luminescent Coatings With The Use Of Low Melting Glass, Eygeniy N. Poddenezhny, Ekaterina E. Trusova, Andrei A. Boiko, Ekaterina R. Kravcova, Olga V. Davydova
Formation Of Luminescent Coatings With The Use Of Low Melting Glass, Eygeniy N. Poddenezhny, Ekaterina E. Trusova, Andrei A. Boiko, Ekaterina R. Kravcova, Olga V. Davydova
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of the present research is to develop compounds and technologies for applying the luminous vitrocrystalline compounds to smooth and ribbed glass substrates in LED lamp structure with a remote photoconverter that contains oxide low melting glass as the base and nanostructured cerium–doped yttrium–aluminum garnet powder as the luminophore. The luminescent coatings based on nanostructured cerium doped yttrium-aluminum garnet powder and low melting glass of composition BaO-Bi2O3-B2O3-K2O-SiO2 where prepared. YAG:Ce3+ powder was synthesized by the method of thermochemical reaction. Silica glass powder was introduced into the composition …
Anomalous Of Resistance And Magnetic Susceptibility At 280-310 K And Ambient Pressure In Bismuth Cuprates Synthesized By Solar Energy, Dilbara Dj. Gulamova, Elyor B. Eshonkulov, Valeriya R. Li, Grigor I. Mamniashvili, Timur I. Gulamov
Anomalous Of Resistance And Magnetic Susceptibility At 280-310 K And Ambient Pressure In Bismuth Cuprates Synthesized By Solar Energy, Dilbara Dj. Gulamova, Elyor B. Eshonkulov, Valeriya R. Li, Grigor I. Mamniashvili, Timur I. Gulamov
CHEMISTRY AND CHEMICAL ENGINEERING
In order to obtain the full content of high-temperature superconducting phases using the “Super Fast Alloys Quenching” technology in the Large Solar Furnace (Parkent), precursors of bismuth cuprates of the series Bi1,7Pb0,3Sr2Ca(n-1)CunOy, n=3-30 were synthesized. Methods for study the properties of precursors are presented. The oriented nano-sized microstructure and layered structure of nanocrystalline nuclei are shown. The phase composition of the precursors at the beginning of the series (n=3-5) is represented by X-ray amorphous and crystalline phases. An increase in the content of CaO and CuO destabilizes the …
Waste Utilization In Korean Cement Plants, Geun-Seong Lee, Zebo Abdullaevna Babakhanova, Mastura Khikmatovna Aripova
Waste Utilization In Korean Cement Plants, Geun-Seong Lee, Zebo Abdullaevna Babakhanova, Mastura Khikmatovna Aripova
CHEMISTRY AND CHEMICAL ENGINEERING
The kiln process in cement plant has the advantage of completely and effectively destroying and burning all organic substances due to high temperature and long residence time, oxygen atmosphere and excellent mixing effect, alkaline conditions of raw materials, and incorporation of trace metals into clinker, and plays a role as a pollutant emission barrier during waste utilization. Waste utilization technology is now proven and successful in cement plants. The waste utilization in Korean cement plants are greatly expanding in the view of energy and material recoveries, and economics as well as environmental preservation. Research on waste utilization in the Korean …
Study Of Kinetics Of Hydrocarbon Gas Purification With Composite Absorbents, Oybek Aripdjanov, Shavkat Nurullaev, Shodiyakhon Azimova
Study Of Kinetics Of Hydrocarbon Gas Purification With Composite Absorbents, Oybek Aripdjanov, Shavkat Nurullaev, Shodiyakhon Azimova
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of the work is to improve the process of natural gas purification from acidic components using a composite absorbent. To study the sorption of acidic components in the gas composition, a chromatographic analysis method was used. The kinetics and rate of corrosion of carbon steel grade st.10 when using composite absorbents MDEA +DEA + AVRP have been studied. The results of the study show that the volume of absorption increased from 0.55 mol/mol to 0.65 mol/mol, and the amount of H2S in the purified gas decreased from 0.022 g/m3 to 0.014 g/m3. Corrosion …
Study Of Reactive Distillation Equipment For Eterification Process, Abbos Elmanov, Abdulaziz Bakhtiyorov, Adham Norkobilov, Olimjon Maksudov, Zarif Oripov
Study Of Reactive Distillation Equipment For Eterification Process, Abbos Elmanov, Abdulaziz Bakhtiyorov, Adham Norkobilov, Olimjon Maksudov, Zarif Oripov
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of this work is to study the chemical technological processes for eterification processes, and the reactive distillation unit, which carries out the reaction and separation process in one device, was chosen as the object of research. А reаctive distillаtion system is exаmined to produce for the production of Ethyl Acetate (EtAc) viа eterificаtion of acetic acid (HAc) with ethаnol. Optimizаtion methods using sensitivity analysis аre аlso conducted. Cаlculаtion of vаpor liquid equilibrium of the mixture system is done using UNIFАC model. Heat integration from the distillate stream of the column to the acid feed stream and from bottom …
Modeling And Performance Analysis Of Solid Oxide Fuel Cell, Mariya Pecherskaya, Khakimjan Butanov, Suhrob A. Ibodullaev, Olim Ruzimuradov, Shavkat Mamatkulov
Modeling And Performance Analysis Of Solid Oxide Fuel Cell, Mariya Pecherskaya, Khakimjan Butanov, Suhrob A. Ibodullaev, Olim Ruzimuradov, Shavkat Mamatkulov
CHEMISTRY AND CHEMICAL ENGINEERING
A three-dimensional numerical model of the system configurations of various types of solid oxide fuel cells (SOFCs) is used and the effect of parameters on SOFC performance is numerically investigated using COMSOL Multiphysics. The effect of parameters such as support layer thickness, operating temperature, and electrode porosity are shown in the polarization and power curves for each model. The results of the study showed the advantages of the anode-supported SOFC compared to cathode- and electrolyte-supported SOFC.
Theoretical calculations demonstrate the highest output power density in the anode-supported SOFC at 900 ℃, and reach a value of 0.585 W cm-2 …
Alkynylation Of Benzaldehyde And Its R-Substituted Derivatives Based On Lithium Phenylacetylenide, Sanat B. Samatov, Odiljon E. Ziyadullayev, Abduvakhab Ikramov
Alkynylation Of Benzaldehyde And Its R-Substituted Derivatives Based On Lithium Phenylacetylenide, Sanat B. Samatov, Odiljon E. Ziyadullayev, Abduvakhab Ikramov
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of this research work is for the first time the synthesis of the corresponding acetylene alcohols based on the alkynylation reaction of isolated benzaldehyde and its R-substituted derivatives in the BuLi/TGF system. The study proposed the reaction stages for the synthesis of acetylene alcohols in the selected BuLi/TGF system, the influence of factors influencing the process, including temperature, reaction duration and nature selected solvents. The structure of the synthesized acetylene alcohols was confirmed by modern methods of physicochemical analysis (1H NMR, 13C NMR). In addition, the effect of substituents in benzaldehyde and its R-substituted derivatives …
Numerical Calculation Of The Flame Spreading Over A Methane Hydrate Surface, Otabek Nigmatov, Oksana Ismailova
Numerical Calculation Of The Flame Spreading Over A Methane Hydrate Surface, Otabek Nigmatov, Oksana Ismailova
CHEMISTRY AND CHEMICAL ENGINEERING
The Methane Hydrate is expected as an energy source and is being as a medium distance transport means of natural gas alternative of LNG (Liquefied Natural Gas). During the natural gas transportation, fire accidents are concerned. In the present study, the flame spreading over a methane hydrate surface has been studied numerically as a function of hydrate surface temperature, Ts. When Ts = 173 K (-100℃), lower than the dissociation temperature (Td = 183 K (-90℃)), the flame spreading speed is around 6.5 mm/s, while the flame spreading speed at Ts = 193 K (-80℃), …
Dft Study Of Quantum Chemical Parameters Of 4-Amino-2-Mercaptobenzimidazole And Their Tautomeric Forms, Dilnoza Rahmonova, Alisher Eshimbetov, Lobar Gapurova, Zuhra Ch. Kadirova, Shakhnoza Kadirova
Dft Study Of Quantum Chemical Parameters Of 4-Amino-2-Mercaptobenzimidazole And Their Tautomeric Forms, Dilnoza Rahmonova, Alisher Eshimbetov, Lobar Gapurova, Zuhra Ch. Kadirova, Shakhnoza Kadirova
CHEMISTRY AND CHEMICAL ENGINEERING
Coordination competing donor centers, electronic and geometric structures of the 4-amino-2-mercaptobenzimidazole ligand molecule were studied using quantum chemical calculation by the DFT / 6-31G method (d, p). It was shown that during the formation of the metal complex, the ligand is coordinated through the localized nitrogen atom of the imidazole ring. In this study, the total energies (Etot) of 4-amino-2-mercaptobenzimidazole (1) and its tautomeric forms (2 and 3) were calculated. And also, the energies of boundary molecular orbitals, the energy gap between boundary MOs (ΔE) and the distribution of the total charge on atoms and boundary orbitals were determined. In …
The Effect Of Hydrogen Peroxide And Potassium Amylxanthate On The Surface Properties Of Chalcocite And Enargite, Berdakh T. Daniyarov, Hajime Miki, Daminbek A. Ziyatov, Shahlo Daminova
The Effect Of Hydrogen Peroxide And Potassium Amylxanthate On The Surface Properties Of Chalcocite And Enargite, Berdakh T. Daniyarov, Hajime Miki, Daminbek A. Ziyatov, Shahlo Daminova
CHEMISTRY AND CHEMICAL ENGINEERING
The effect on the surface properties and floatability of chalcocite and enargite after oxidative treatment with hydrogen peroxide (H2O2) in the presence and absence of potassium amylxanthate (PAX) as a collector was studied. In this research, flotation tests were carried out on mixed and individual minerals. Oxidative treatment with hydrogen peroxide had a negative effect on the floatability of chalcocite and enargite. PAX adsorption analysis shows that enargite adsorbs PAX faster than chalcocite. Moreover, Fourier transform infrared spectroscopy analysis shows that PAX was adsorbed in the form of copper amylxanthate on chalcocite and enargite surfaces. In …
Influence Of The Amount Of Monoethanolamine On The Physicochemical Properties Of Aminolysis Products, Soxibjon A. Egamberdiyev, Muzaffar G. Alimukhamedov, Juraev Asror, Ravshan Adilov
Influence Of The Amount Of Monoethanolamine On The Physicochemical Properties Of Aminolysis Products, Soxibjon A. Egamberdiyev, Muzaffar G. Alimukhamedov, Juraev Asror, Ravshan Adilov
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of this paper is to investigate the process of aminolysis of secondary polyethylene terephthalate with monoethanolamine at low ratio. The effect of the amount of monoethanolamine on the physical and chemical properties of the aminolysis product of secondary polyethylene terephthalate was studied. With an increase of 1-4 moles of monoethanolamine obtained for synthesis (without the presence of a catalyst), it was observed that the number of amines in the aminolysis product increased from 324 to 503 mgKON/g, and the number of hydroxyls increased from 298 to 491 mgKON/g. The structure of the resulting bis(2-hydroxyethylene)terephthalamide was studied using IR …
Study Of The Structure Of Glass Ionomer Cements Developed Based On Glass System Sio2-Al2o3-Cao-Zno-P2o5-Caf2, Tatyana O. Nam, Mastura X. Aripova, Ripsime V. Mkrtchyan
Study Of The Structure Of Glass Ionomer Cements Developed Based On Glass System Sio2-Al2o3-Cao-Zno-P2o5-Caf2, Tatyana O. Nam, Mastura X. Aripova, Ripsime V. Mkrtchyan
CHEMISTRY AND CHEMICAL ENGINEERING
The goal was to study the structure of glass ionomer cements (GIC) developed on the basis of glasses of the SiO2-Al2O3-CaO-ZnO-P2O5-CaF2 system. Glass powders with sizes less than 50 μm were sealed with a 40% solution of polyacrylic acid and after 72 hours, electron microscopic examination was carried out on a JSM-IT200 scanning microscope (JEOL, Japan). All samples demonstrate a cellular structure consisting of glass particles surrounded by glass elements that have entered into an acid-ion interaction with polyacrylic acid in a polymer matrix. GIC-4 and GIC-6 show the most …
Impact Of Sulfurization On Sputtered Bivo4 Thin Films, Shukur P. Gofurov, Dilbar T. Bozorova, Zuhra Ch, Kadirova, Oksana Ismailova
Impact Of Sulfurization On Sputtered Bivo4 Thin Films, Shukur P. Gofurov, Dilbar T. Bozorova, Zuhra Ch, Kadirova, Oksana Ismailova
CHEMISTRY AND CHEMICAL ENGINEERING
The sulfurization method has been used to decrease the band gap of the BiVO4 structure, reduce the recombination of electrons and holes, and increase the photoelectrochemical performance of this material. It has been observed that incorporation of sulfur into stoichiometric and Vrich BiVO4 is variously affected changing of properties of the structure. Sulfurization can modify Vrich BiVO4 structure rather than stoichiometric BiVO4.
Development Of Clinker And Portland Cement Composition Based On Surkhondaryo Raw Materials, Salohiddin Ramazanov, Abdumalik Nabiyev, Mastura Aripova
Development Of Clinker And Portland Cement Composition Based On Surkhondaryo Raw Materials, Salohiddin Ramazanov, Abdumalik Nabiyev, Mastura Aripova
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of this research work is to develop clinker and Portland cement compositions based on Surkhandarya raw materials for the planned construction of a cement plant, as well as to study their physical and chemical properties. The compositions of clinkers, including limestone, clay from the Yolgizbulok deposit and slag from the Almalyk mining and metallurgical plant, were studied. The optimal clinker composition was selected, on the basis of which Portland cement was obtained. The optimal amount of gypsum addition was determined to achieve a cement stone strength of 43,5 MPa. The developed clinker composition will provide the planned enterprise …
Antibacterial Cerium-Containing Glazes For Ceramic Tiles, Ivan Levitskiy, Mastura Aripova, Mihail Dyadenko, Dar’Ya Kucherova, Artem Golub
Antibacterial Cerium-Containing Glazes For Ceramic Tiles, Ivan Levitskiy, Mastura Aripova, Mihail Dyadenko, Dar’Ya Kucherova, Artem Golub
CHEMISTRY AND CHEMICAL ENGINEERING
The results of research on the production of semi-fritted cerium-containing glazes used for ceramic tiles are presented.
A multicomponent raw material mixture based on dolomite, cerium dioxide CeO2, aluminosilicate multicalcium frit and permanent components including feldspar, alumina and clay components (kaolin and refractory clay) is used to produce glazes.
The characteristics of the obtained coatings were studied: appearance, technological and physico-chemical properties, including antibacterial properties in relation to the strains of Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 6538. The influence of temperature parameters on the formation of glaze coatings, as well as their structure and phase …
Energy And Resource-Saving Method For Enriching The Waste Water Purified Without Sufficient Purification With Oxygen, Dilobar Khurramova, Mukhtor Khurramov, Sharifa Ganieva, Zulqaynar Nazirov
Energy And Resource-Saving Method For Enriching The Waste Water Purified Without Sufficient Purification With Oxygen, Dilobar Khurramova, Mukhtor Khurramov, Sharifa Ganieva, Zulqaynar Nazirov
CHEMISTRY AND CHEMICAL ENGINEERING
In order to implement a reliable and environmentally safe, economically viable method of wastewater enrichment, the goal is to develop an energy- and resource-saving method of oxygen enrichment of wastewater that has not undergone sufficient treatment. Cleaning is carried out in a tank, which is built using rock, which is an algal limestone. Limestone contributes to the improvement of the oxygen regime due to the “conservation” of organic matter in anoxic bottom layers and the acceleration of the process of photosynthesis of unicellular algae. Calcium carbonate is a reagent that provides not only automatic stabilization of water pH at 2/dm …
Kinetics Of Carboxymethylation Reaction Of Cellulose Samples With Different Degree Of Crystallinity, Ilkhom Goyibnazarov, Sherzod Yuldoshov, Abdushukhur Sarimsokov
Kinetics Of Carboxymethylation Reaction Of Cellulose Samples With Different Degree Of Crystallinity, Ilkhom Goyibnazarov, Sherzod Yuldoshov, Abdushukhur Sarimsokov
CHEMISTRY AND CHEMICAL ENGINEERING
No abstract provided.
Mathematical Modeling Of Synthesis 4´,4´´-Di-(1-Methyl-1-Hydroxy-2-Phenylethynyl)-Dibenzo-18-Crown-6, Lyubov Kozinskaya, Dilorom Mirkhamitova
Mathematical Modeling Of Synthesis 4´,4´´-Di-(1-Methyl-1-Hydroxy-2-Phenylethynyl)-Dibenzo-18-Crown-6, Lyubov Kozinskaya, Dilorom Mirkhamitova
CHEMISTRY AND CHEMICAL ENGINEERING
The main goal of this study is the mathematical modeling of the optimal conditions for the synthesis of 4´,4´´-di-(1-methyl-1-hydroxy-2-phenylethynyl)-dibenzo-18-crown-6 by the least squares method. In the STAT program, iconograms of mathematical modeling of the synthesis and the dependence of the rate of formation of 4´,4´´-di-(1-methyl-1-hydroxy-2-phenylethynyl)-dibenzo-18-crown-6 on temperature and reaction time were obtained, the corresponding analytical dependencies are determined. Mathematical processing of the results of the synthesis of 4´,4´´-di-(1-methyl-1-hydroxy-2-phenylethynyl)-dibenzo-18-crown-6 was carried out, a system of linear equations was compiled using the matrix method. The average reaction rate and the optimum of the mathematical model were determined, and the experimental and calculated …
Synthesis Of Aromatic Acetylene Alcohols Based On Benzaldehyde And Its Halogenated Products, Sanat Samatov, Abduvakhab Ikramov, Saida Abdurakhmanova, Odiljon Ziyadullayev, Guzal Otamukhamedova
Synthesis Of Aromatic Acetylene Alcohols Based On Benzaldehyde And Its Halogenated Products, Sanat Samatov, Abduvakhab Ikramov, Saida Abdurakhmanova, Odiljon Ziyadullayev, Guzal Otamukhamedova
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of this study is to synthesize the corresponding aromatic acetylenic alcohols by alkylation with phenylacetylene in a complex catalytic system based on Zn(OTf)2 and TBAF·3H2O for the first time with benzaldehyde and some of its halogen derivatives. The selectivity and stability of catalysts used for the yields of reactions for the synthesis of aromatic acetylene alcohols were analyzed. The effect of benzaldehyde and its halogenated derivatives on the product yield was analyzed. The nature, structure, isomerism, spatial structure and other properties influenced to this reactions were studied. Some features of reactions of synthesis of aromatic …
Study Of Sorption Of Some Metal Ions By The Obtained Phosphoric Acid Cation Exchanger Of Polycondensation Type, Malika Berdieva, Rano Nazirova, Alisher Yuldashev, Umida Sharipova, Dilmurod Azimov
Study Of Sorption Of Some Metal Ions By The Obtained Phosphoric Acid Cation Exchanger Of Polycondensation Type, Malika Berdieva, Rano Nazirova, Alisher Yuldashev, Umida Sharipova, Dilmurod Azimov
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of this work is to investigate the sorption of Cu2+, Co2+, Ni2+, UO22+ ions, etc. depending on the ionic form of the cationite and the pH of the medium on phosphoric acid cationite obtained by forsforylation of a polymer based on cubic waste of the Shurtan gas-chemical complex and a secondary product of the hydrolysis industry – furfural. It was found that copper and UO22+ ions are best sorbed by cationite when the cationite is in Na form. The UO22+ ion is sorbed fairly well in …
Thermal Properties Of Polyelectrolyte Complexes Of Bombyx Mori Chitosan With Collagen, Shuhrat Khudoyberdiev, Noira Vokhidova, Mukhitdin Abdurazakov, Sayora Rashidova
Thermal Properties Of Polyelectrolyte Complexes Of Bombyx Mori Chitosan With Collagen, Shuhrat Khudoyberdiev, Noira Vokhidova, Mukhitdin Abdurazakov, Sayora Rashidova
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of the work was to study the thermal behavior of the polyelectrolyte complexes of Bombyx mori ChS with collagen. As a result of the studies, the thermal properties of polyelectrolyte complexes based on Bombyx mori chitosan with collagen in wt. rel. 1:0,1 and 1:0,2 respectively. It has been determined that the most significant weight changes for chitosan with a molecular weight of 15×103 and the degree of deacetylation of 85% occur at a temperature is 270 °C, when the mass loss rate reaches its maximum value. For collagen, the same temperature is 277 °C. For complexes ChS/collagen …
Glass Micro-Beads For Road Markings On The Basis Of Local Raw Materials, Farrukh Erkinov, Mastura Aripova, Jae-Shin Lee
Glass Micro-Beads For Road Markings On The Basis Of Local Raw Materials, Farrukh Erkinov, Mastura Aripova, Jae-Shin Lee
CHEMISTRY AND CHEMICAL ENGINEERING
One of the priorities for the development of chemical and technological processes in the field of road-building materials and their quality is the production of materials for road markup based on glass micro-beads.
The use of glass micro-beads ensures the required retro-reflection of road marking and indicators of resistance to external influences, compliance with the requirements of regulatory documents. Therefore, the task of developing research approaches to develop a composition and control of road marking, which provide high performance and reduce accidents is an urgent problem.
For this purpose, on the basis of local raw materials, the theoretical foundations of …
Research Of The Process Of Obtaining Crystalline Monocalcium Phosphate Based On Extraction Phosphoric Acid From Phosphorites Of Central Kyzylkums, Kholtura Mirzakulov, Gavkhar Melikulova, Mohichehra Shaymardanova, Sherzod Khujamberdiev
Research Of The Process Of Obtaining Crystalline Monocalcium Phosphate Based On Extraction Phosphoric Acid From Phosphorites Of Central Kyzylkums, Kholtura Mirzakulov, Gavkhar Melikulova, Mohichehra Shaymardanova, Sherzod Khujamberdiev
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of the research is to establish the optimal parameters of the technological process for the production of feed, crystalline monocalcium phosphate based on defluorinated and desulphated extraction phosphoric acid obtained from phosphorites of the Central Kyzylkum and limestone.
The influence of technological parameters, such as the norms and concentration of phosphoric acid, the process temperature on the filtration rate indicators, the rheological properties of the suspension and the mother liquor, as well as the dependence of the change in the commercial property of crystalline feed monocalcium phosphate, were studied.
It is shown that, regardless of the initial acid …
Investigations Of Roasting Process And Fractional Composition Of Zinc Concentrate Of Khandiza Deposit, Jasur Makhmayorov, Zafar Khakimov, Bakhrom Makhkamov, Murodjon Samadiy
Investigations Of Roasting Process And Fractional Composition Of Zinc Concentrate Of Khandiza Deposit, Jasur Makhmayorov, Zafar Khakimov, Bakhrom Makhkamov, Murodjon Samadiy
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of the study is to study the effect of the process of calcining zinc concentrate from the Khandiza deposit on the degree of zinc extraction and fractional composition. For this, the chemical composition of the concentrate was established and it was shown that the main components are zinc, silicon, potassium, calcium, iron, copper, cadmium, and lead. Titanium, manganese, cobalt, and molybdenum are also contained in small amounts.
Extraction of zinc from a concentrate, calcined at 900 °C for 90 minutes with sulfuric acid with concentration of 18-25% in an autoclave at a temperature of 75 °C, a ratio …
Technology For Producing Alumosilicate Refractory Products Based On Non-Traditional Raw Materials Of Uzbekistan, Ripsime Mkrtchyan
Technology For Producing Alumosilicate Refractory Products Based On Non-Traditional Raw Materials Of Uzbekistan, Ripsime Mkrtchyan
CHEMISTRY AND CHEMICAL ENGINEERING
The aim of the study is to develop a technology for producing aluminosilicate refractory products based on non-traditional raw materials - clay shale from the Jerdanak deposit and quartz-pyrophyllite rock from the Boynaksai deposit. The characteristics of prototypes of refractory materials were studied at different ratios of chamotte and binder. Quartz-pyrophyllite rock in its natural state and clay shale after firing at a relatively low temperature (1000 °C) were used as fireclay. The phase composition of the obtained materials was studied by X-ray diffraction and their fine structure by electron microscopy. Technological schemes for obtaining refractory products based on clay …