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Mathematical Modeling Of Synthesis 4´,4´´-Di-(1-Methyl-1-Hydroxy-2-Phenylethynyl)-Dibenzo-18-Crown-6, Lyubov Kozinskaya, Dilorom Mirkhamitova May 2022

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 May 2022

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 May 2022

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 May 2022

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 May 2022

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 May 2022

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 May 2022

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 May 2022

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 …


Administrative Appeal Decision - Watson, Gregory (2018-12-28) May 2022

Administrative Appeal Decision - Watson, Gregory (2018-12-28)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Westfall, Kevin (2019-02-27) May 2022

Administrative Appeal Decision - Westfall, Kevin (2019-02-27)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Fuller, Fitzalbert (2019-01-31) May 2022

Administrative Appeal Decision - Fuller, Fitzalbert (2019-01-31)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Green, Francis (2019-02-06) May 2022

Administrative Appeal Decision - Green, Francis (2019-02-06)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Pelton, Gregory (2019-01-11) May 2022

Administrative Appeal Decision - Pelton, Gregory (2019-01-11)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Jones, William (2018-12-28) May 2022

Administrative Appeal Decision - Jones, William (2018-12-28)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Pagan, Xavier (2019-01-19) May 2022

Administrative Appeal Decision - Pagan, Xavier (2019-01-19)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Rivera, Raul (2019-01-31) May 2022

Administrative Appeal Decision - Rivera, Raul (2019-01-31)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Hassenbein, Neil (2018-12-28) May 2022

Administrative Appeal Decision - Hassenbein, Neil (2018-12-28)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Puente, Orlando (2018-12-28) May 2022

Administrative Appeal Decision - Puente, Orlando (2018-12-28)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Pough, Kevin (2018-12-28) May 2022

Administrative Appeal Decision - Pough, Kevin (2018-12-28)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Stanley, Jules (2018-12-28) May 2022

Administrative Appeal Decision - Stanley, Jules (2018-12-28)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Velez, Jose (2019-01-31) May 2022

Administrative Appeal Decision - Velez, Jose (2019-01-31)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Vanalstine, David (2019-02-06) May 2022

Administrative Appeal Decision - Vanalstine, David (2019-02-06)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Blyther, Derrick (2019-02-06) May 2022

Administrative Appeal Decision - Blyther, Derrick (2019-02-06)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Chatman, Corey (2018-12-28) May 2022

Administrative Appeal Decision - Chatman, Corey (2018-12-28)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Morales, Carmelo (2019-01-30) May 2022

Administrative Appeal Decision - Morales, Carmelo (2019-01-30)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Bucknor, Cornelius (2019-01-31) May 2022

Administrative Appeal Decision - Bucknor, Cornelius (2019-01-31)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Kirkland, Anthony (2019-01-11) May 2022

Administrative Appeal Decision - Kirkland, Anthony (2019-01-11)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Howard, Stanley (2019-02-27) May 2022

Administrative Appeal Decision - Howard, Stanley (2019-02-27)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Woods, Perry (2019-02-27) May 2022

Administrative Appeal Decision - Woods, Perry (2019-02-27)

Parole Administrative Appeal Decisions

No abstract provided.


Administrative Appeal Decision - Power, Sidney (2019-02-27) May 2022

Administrative Appeal Decision - Power, Sidney (2019-02-27)

Parole Administrative Appeal Decisions

No abstract provided.