Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

164,155 Full-Text Articles 195,368 Authors 56,080,941 Downloads 330 Institutions

All Articles in Engineering

Faceted Search

164,155 full-text articles. Page 6 of 4931.

Configuration And Competitive Reactivity Of Ligands In Mixed Ligand Complexes Of Dialkylditiophosphates And Aminobenbenzimidazole (Part I: Au, Pt, Ag), ESBERGENOVA Botakoz, DAMINOVA Shakhlo, KADIROVA Zuhra, SHARIPOV Khasan 2020 State Enterprise “Uzbek-Japanese Youth Innovation Center”

Configuration And Competitive Reactivity Of Ligands In Mixed Ligand Complexes Of Dialkylditiophosphates And Aminobenbenzimidazole (Part I: Au, Pt, Ag), Esbergenova Botakoz, Daminova Shakhlo, Kadirova Zuhra, Sharipov Khasan

CHEMISTRY AND CHEMICAL ENGINEERING

With the aim of determination of electronic and geometrical structures of mixed-ligand complexes, theoretical modeling of the structures of coordination compounds of transition metals with dialkyldithiophosphate chelating ligands with aminobenzimidazoles carried out using quantum chemical methods. Using BIOVIA Materials Accelrys Studio 2017 software packages, the geometry, electron density distribution, and frontier orbitals calculated for the mixed ligand complexes of Au(III), Pt(II), Ag(I), Cu(II), Ni(II), Fe(III), which are necessary for understanding the electronic structure of coordination compounds with chelating ligands.


Educational Cluster - Foundation Of The National Economy And Regional Innovation System, USMONOV Botir, KUSHIEV Khabibjon 2020 Tashkent Chemical-Technological Institute

Educational Cluster - Foundation Of The National Economy And Regional Innovation System, Usmonov Botir, Kushiev Khabibjon

CHEMISTRY AND CHEMICAL ENGINEERING

The paper analyzes the available resources for the creation of a cluster approach to the integration of education, science and industry in order to create a mechanism to bring the development of the economy to the level of modern requirements. The article describes the collaboration of science, education and industry through the clustering process. Ways to introduce clustering in the national innovation system are described. At the same time, the role of the integration of education, science and industry with the elements of the National Innovation System is analyzed. In conclusion, the role of the education cluster in the regional ...


Study Of Recombinant Protein Fractions From The Bombyx Mori And Pichia Pastoris Using "Native Page" Method, Abdurhakhmanov aloliddin, Sasmakov Sobirdjan, Khasanov Shuhrat, Ashirov Оybek 2020 Institute of the Chemistry of Plant Substances

Study Of Recombinant Protein Fractions From The Bombyx Mori And Pichia Pastoris Using "Native Page" Method, Abdurhakhmanov Aloliddin, Sasmakov Sobirdjan, Khasanov Shuhrat, Ashirov Оybek

CHEMISTRY AND CHEMICAL ENGINEERING

We have studied the recombinant protein fractions of ? 24-34 kDa obtained from Bombyx mori - silkworm larvae and yeast Pichia pastoris. Fractions, containing the recombinant proteins by gel-electrophoresis using the “Native PAGE” method, which allows for differentiation of proteins according to their natural (surface) charge and conformational properties were studied. The results showed that the recombinant protein fraction from Bombyx mori (? 34 kDa) consisted of four components and fraction from Pichia pastoris (? 24 kDa) consisted one component. The most optimal conditions for the “Native PAGE”- the main gel: Tris HCl (pH-8.8) 244 mM, Bis-Acrylamide 10%, TEMED 0.08%, APS 0 ...


Pressure-Compensated Temperature Control In Rectification Column, Norkobilov Adham, Turakulov Zafar, Kamolov Azizbek, Talipov Hojiakbar 2020 Shahrisabz Branch of the Tashkent Institute of Chemical Technology

Pressure-Compensated Temperature Control In Rectification Column, Norkobilov Adham, Turakulov Zafar, Kamolov Azizbek, Talipov Hojiakbar

CHEMISTRY AND CHEMICAL ENGINEERING

The focus of this work is to study the control of a rectification column (RC) for separating n-butane (nC4) and n-pentane (nC5) mixtures. Two control structures based on conventional temperature control (TC) and pressure-compensated control (PTC) structures are studied and compared using Aspentech software. The control performance of TC and PTC are investigated in terms of the control of component purities in both distillate and bottoms streams, under various disturbances in feed and pressure conditions. Due to pressure compensation, PTC is superior to TC in terms of purity and impurity control under disturbances in feed and pressure conditions. Accordingly, simulation ...


Research Of Kinetic Characteristics Of The Process Of Decomposition Of Zinc Concentrate With Hydrochloric Acid, Rosilov Mansur, Deng Tianlong, Usmanov Ilham, Samadiy Murodjon 2020 Tashkent Chemical Technological Institute

Research Of Kinetic Characteristics Of The Process Of Decomposition Of Zinc Concentrate With Hydrochloric Acid, Rosilov Mansur, Deng Tianlong, Usmanov Ilham, Samadiy Murodjon

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study was the theoretical justification of the kinetic characteristics of the process of producing zinc chloride from zinc concentrate of the Khandiza deposit. For this, the effect of temperature and duration of the process of autoclave zinc extraction in a 28% hydrochloric acid solution was studied at a ratio of Zn: HCI = 1:1.1. Variable parameters were the temperature of 70, 80 and 90 °C and the duration of the leaching process of 6, 8 and 10 hours. The optimal parameters for the production of zinc chloride were determined.


The Study Of The Component Composition Of The Reaction Mixture Containing Formaldehyde Reaction Products, Hurramov Lochinbek, Alimukhamedova Nozima, Adilov Ravshan, Alimukhamedov Muzafar 2020 Tashkent Chemical-Technological Institute

The Study Of The Component Composition Of The Reaction Mixture Containing Formaldehyde Reaction Products, Hurramov Lochinbek, Alimukhamedova Nozima, Adilov Ravshan, Alimukhamedov Muzafar

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to study the effect of the conditions of the reaction of monoethanolamine (Meol) with formaldehyde (FD) on the composition of the reaction mixture. Interaction of monoethanolamine with formaldehyde leads to the formation of N,N’,N”-tris(β-oxyethyl) hexahydro-S-triazine or N,N-bisoxazolidine. The type of final product was determined by the conditions of the reaction and the molar ratio of aminoalcohol:formaldehyde. The chromatogram of the vacuum-distilled final product obtained at the molar ratio of monoethanolamine:formaldehyde=1:1 shows on an individual compound with a retention time of 4.173 s. With increase ...


Obtaining Microcrystalline Cellulose From Melon Crops And Studying Its Structure, Umarova Vasila, Mardonov Asror, Khamdamova Dilnoza, Akmalova Guzal 2020 Tashkent Chemical-Technological Institute

Obtaining Microcrystalline Cellulose From Melon Crops And Studying Its Structure, Umarova Vasila, Mardonov Asror, Khamdamova Dilnoza, Akmalova Guzal

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study was to obtain microcrystalline cellulose from gourds. Cellulose was isolated from the stems of watermelon and pumpkin by acid and alkaline heat treatment. Microcrystalline cellulose was obtained from cellulose by hydrolysis. Cellulose was hydrolyzed in a mixture of sulfuric acid and hydrogen peroxide. The optical parameters of the microcrystalline cellulose sample, ash content, bulk density, water swelling, and moisture sorption were determined. The structural features of the obtained microcrystalline cellulose were studied by IR spectroscopy. The functional groups present under various conditions for the production of microcrystalline cellulose were determined. The influence of the duration ...


Radiopaque Activity Of Iodine Containing Methylene-Bis-Carbamate, Baltabaev Ubaydulla, Djuraev Abdukahhor, Abduvakilov Jahongir, Abdullaeva Matluba 2020 Tashkent state dental institute

Radiopaque Activity Of Iodine Containing Methylene-Bis-Carbamate, Baltabaev Ubaydulla, Djuraev Abdukahhor, Abduvakilov Jahongir, Abdullaeva Matluba

CHEMISTRY AND CHEMICAL ENGINEERING

Considering that many derivatives of bis carbamates have different biological activity, it was intuitive to produce a targeted synthesis of new derivatives of bis carbamates by the interaction of hexamethylene diisocyanate with 3,5-diode-4-hydroxybenzoic acid and 2,4,6-triiodophenol (1: 2 mol, respectively) in freshly distilled dry pyridine at 95-110 оC for 6 hours, the corresponding derivatives were obtained - methylene bis carbamates. Experimental studies have been conducted to identify the acute toxicity and radiopaque properties of the synthesized new N, -hexamethylene bis (2,6-diode-4-carboxyphenylcarbamate).


Modification Of Lithium Lubricants, Azimova Shodiyakhon, Arslanov Sharafutdin, Aripdjanov Oybek, Azimov Dilmurod 2020 Tashkent Chemical-Technological institute

Modification Of Lithium Lubricants, Azimova Shodiyakhon, Arslanov Sharafutdin, Aripdjanov Oybek, Azimov Dilmurod

CHEMISTRY AND CHEMICAL ENGINEERING

The aim is to study the effect of the presence of free alkalis and acids on the properties of the complex lithium greases and the choice of the optimal dispersion medium, which provides the required physicochemical characteristics of the developed grease. The dispersed phase of lithium greases studied in the polyalphaolefin oils media. It was found that the use of a mixture of polyalphaolefin oil-4 and polyalphaolefin oil-40 as a percentage of 23/77 with a total content of 83.0% provides a relatively low effective viscosity of the lubricant at low temperatures and a relatively high tensile strength at ...


Effective Oil Extraction From Bombyx Mori Silkworm Pupae And Its Structural Characteristics, Avazova Oynavod, Yugai Sveta, Rashidova Sayora 2020 Institute of Chemistry and Physics of Polymers

Effective Oil Extraction From Bombyx Mori Silkworm Pupae And Its Structural Characteristics, Avazova Oynavod, Yugai Sveta, Rashidova Sayora

CHEMISTRY AND CHEMICAL ENGINEERING

The conditions for the effective isolation of oil from the silkworm Bombyx mori pupae, based on the extraction of extracted oil with organic reagents, have been studied. The quantitative content of oil was determined in the samples. It is revealed that the oils extracted using gasoline have a high fat-wax composition compared with ethyl alcohol and hexane. When dried pupae processed with gasoline, it is possible to extract up to 16% of fatty substances as much as possible. Physical-chemical characteristics of the oil from silkworm pupae are characterized by high quality indicators. In particular, the presence of unsaturated fatty acids ...


Composition Of Liquid Paraffins For Flotation Enrichment Of Potassium Chloride, Vaqqosov Sobir, Xolmuratov Shamsitdin, Buxarov Shuhrat, Kodirov Orifjon 2020 Jizzakh Polytechnic Institute

Composition Of Liquid Paraffins For Flotation Enrichment Of Potassium Chloride, Vaqqosov Sobir, Xolmuratov Shamsitdin, Buxarov Shuhrat, Kodirov Orifjon

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work is to determine the source of liquid paraffins from secondary products of the local chemical industry, compare the performance properties and use the resulting products as apolar co-reagents in silvinite flotation. The experiments were conducted with secondary used hexane and pyrocondensation. To improve the efficiency of flotation, the dependences of the order of reagent’s supply into the process and the time of action were studied. Experiments have shown that when adding tetradecane and pentadecane in an amount of 2.5 to 7.5% to hexane liquid paraffins, it is possible to reduce the tail ...


Influence Of Technological Parameters On The Chemical Composition Of Calcium Polyphosphates From Phosphorites Central Kyzylkum, Ulugberdieva Ziyada, Khujamberdiev Sherzod, Mirzakulov Kholtura, Usmanov Ilkham 2020 Tashkent Chemical-Technological Institute

Influence Of Technological Parameters On The Chemical Composition Of Calcium Polyphosphates From Phosphorites Central Kyzylkum, Ulugberdieva Ziyada, Khujamberdiev Sherzod, Mirzakulov Kholtura, Usmanov Ilkham

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the research was to study the effect of temperature, the ratio of P2O5EPA:P2O5PRM and the duration of calcination on the content of various forms of P2O5 in calcium polyphosphate. The effect of calcination temperature from 150 to 300 °C, the ratio of P2O5EPA:P2O5FRM from 2,15 to 4,50 and the duration of the process from 20 to 120 minutes on the changes in various forms of P2O5 were studied. It was shown that with increasing temperature to 200-250 °C the content of the total (ortho + poly) assimilable form of Р2О5 increases and then decreases ...


Bases Of Development Of Technologies Of Synthesis Of Oxide Materials In Big Solar Furnace (Parkent), Gulamova Dilbara, Baxronov Khayot, Bobokhulov Sirojiddin, Eshonkulov Elyor 2020 Institute of Materials Science

Bases Of Development Of Technologies Of Synthesis Of Oxide Materials In Big Solar Furnace (Parkent), Gulamova Dilbara, Baxronov Khayot, Bobokhulov Sirojiddin, Eshonkulov Elyor

CHEMISTRY AND CHEMICAL ENGINEERING

The advantages of synthesis of complex oxide compounds by solar energy, the possibility of obtaining highly textured nano materials are shown. The development of heliomaterial science, aimed at the synthesis of new materials, is inextricably linked with the use of effective optical energy systems. On the example of obtaining superconducting materials of nominal composition Bi1.7Pb0.3Sr2Ca(n-1)CunOy (n = 3-20), optimization of the parameters of the optical-energy system of the Big Solar Furnace (Parkent) is shown. The ideology of developing heliotechnology for the synthesis of inorganic materials in a solar furnace is presented. The properties of a superconducting material ...


A Polymer Gel Index-Matched To Water Enables Diverse Applications In Fluorescence Microscopy [Preprint], Xiaofei Han, Yijun Su, Hamilton White 2020 Tsinghua University

A Polymer Gel Index-Matched To Water Enables Diverse Applications In Fluorescence Microscopy [Preprint], Xiaofei Han, Yijun Su, Hamilton White

University of Massachusetts Medical School Faculty Publications

We demonstrate diffraction-limited and super-resolution imaging through thick layers (tens-hundreds of microns) of BIO-133, a biocompatible, UV-curable, commercially available polymer with a refractive index (RI) matched to water. We show that cells can be directly grown on BIO-133 substrates without the need for surface passivation and use this capability to perform extended time-lapse volumetric imaging of cellular dynamics 1) at isotropic resolution using dual-view light-sheet microscopy, and 2) at super-resolution using instant structured illumination microscopy. BIO-133 also enables immobilization of 1) Drosophila tissue, allowing us to track membrane puncta in pioneer neurons, and 2) Caenorhabditis elegans, which allows us to ...


A User Study Of A Wearable System To Enhance Bystanders’ Facial Privacy, Alfredo J. Perez, Sherali Zeadally, Scott Griffith, Luis Y. Matos Garcia, Jaouad A. Mouloud 2020 Columbus State University

A User Study Of A Wearable System To Enhance Bystanders’ Facial Privacy, Alfredo J. Perez, Sherali Zeadally, Scott Griffith, Luis Y. Matos Garcia, Jaouad A. Mouloud

Information Science Faculty Publications

The privacy of users and information are becoming increasingly important with the growth and pervasive use of mobile devices such as wearables, mobile phones, drones, and Internet of Things (IoT) devices. Today many of these mobile devices are equipped with cameras which enable users to take pictures and record videos anytime they need to do so. In many such cases, bystanders’ privacy is not a concern, and as a result, audio and video of bystanders are often captured without their consent. We present results from a user study in which 21 participants were asked to use a wearable system called ...


Modeling Land And Hold Short Operations: Balancing Safety And Arrival Rate, Kenneth A. Ward, Heather Owen-Perry 2020 Embry-Riddle Aeronautical University

Modeling Land And Hold Short Operations: Balancing Safety And Arrival Rate, Kenneth A. Ward, Heather Owen-Perry

Journal of Aviation Technology and Engineering

Many airports conduct simultaneous operations on intersecting runways to increase the rate of takeoffs and landings. This requires landing aircraft to hold short of the intersecting runway, which incurs a safety risk of runway incursions in the process. A Monte Carlo simulation was conducted to analyze the traffic load at maximum operational capacity at Charlotte-Douglas International Airport in order to analyze the fleet types and the rate of those landing aircraft unable to stop short of the intersecting runway. The researchers used the actual and four alternative compositions of the subject airline’s aircraft arrivals, interspersed among other airport traffic ...


Measurement Of Surface Subsidence And Ground Collapse Caused By Underground Mining In The Boleo Copper District, Mexico, Jong-Gwan Kim 2020 Department of Energy and Resources Engineering, Chonnam Nationa University, Korea

Measurement Of Surface Subsidence And Ground Collapse Caused By Underground Mining In The Boleo Copper District, Mexico, Jong-Gwan Kim

Journal of Sustainable Mining

Subsidence and vertical movements in mines are a challenge in mining operations. To qualify as a controlled mine site, ground movements must be measured regularly during mining operations. Boleo Copper District mine was monitored and the movement during mining operations was measured from Oct. 31, 2018 to March 15, 2019. The evaluation of vertical and horizontal movement was determined in four locations in the mine areas M303, M303S, M303 C, and M305. The exploitation area, which measured approximately 80 x 90 m2 with a height of 2.4 m, impacted the surface in the form of cracks. These cracks ...


Recovery And Repurposing Of Thermal Resources In The Mining And Mineral Processing Industry, Shannon H. McLean, Jeffrey Chenier, Sari Muinonen, Corey A. Laamanen, John A. Scott 2020 School of Engineering, Laurentian University, 935 Ramsey Lake Road, Sudbury, ON, Canada

Recovery And Repurposing Of Thermal Resources In The Mining And Mineral Processing Industry, Shannon H. Mclean, Jeffrey Chenier, Sari Muinonen, Corey A. Laamanen, John A. Scott

Journal of Sustainable Mining

The consumption of energy contributes significantly to the overall cost of operations and the environmental impact of the mining and mineral processing industry. However, despite a few notable exceptions, most of the resulting waste heat produced is dissipated, without recovery, into the environment. There is also a lot of stored heat in mine water which can be tapped into long after a mine has closed. There is, therefore, significant opportunity to improve the industry's sustainability through increasing the amount of waste heat recovered and repurposed.


Mineralogical Variations With The Mining Depth In The Congo Copperbelt: Technical And Environmental Challenges In The Hydrometallurgical Processing Of Copper And Cobalt Ores, Michel Shengo Lutandula, W. S. Kitobo, M. B. Kime, M. P. Mambwe, T. K. Nyembo 2020 Inorganic Chemistry Unit, Department of Chemistry, Faculty of the Sciences, University of Lubumbashi, Likasi Avenue, PO BOX 1825, City of Lubumbashi, Haut-Katanga Province, People's Republic of Congo

Mineralogical Variations With The Mining Depth In The Congo Copperbelt: Technical And Environmental Challenges In The Hydrometallurgical Processing Of Copper And Cobalt Ores, Michel Shengo Lutandula, W. S. Kitobo, M. B. Kime, M. P. Mambwe, T. K. Nyembo

Journal of Sustainable Mining

For a long time in the Democratic Republic of Congo, the mining of ores for the production of copper cathodes and salts of cobalt was mostly conducted in the near-surface oxidized mineralization of the Congo Copperbelt. An important part of this mineralization is found in geological settings where copper and cobalt mainly exist as mixtures of oxides and sulfides. With the depletion of surface-rich minerals, mining is taking place at depths where sulfide minerals are prevalent. Using current technologies, the hydrometallurgical processing of ores with high levels of sulfide minerals results in poor metal recovery due to their retention in ...


Alternative Methodology To Determine Effective Coefficient Of Methane Diffusion In Coal, Henryk Koptoń 2020 Experimental Mine 'Barbara', Department of Gas Hazard Control, The Central Mining Institute (Katowice, Poland) ul. Podleska 72, 43- 190, Miko?ów, Poland

Alternative Methodology To Determine Effective Coefficient Of Methane Diffusion In Coal, Henryk Koptoń

Journal of Sustainable Mining

The article presents the results of research in to the development of an alternative method of determining the effective coefficient of methane diffusion in coal, based on a mathematical model following Fick's second law. The research was conducted based on the recorded courses of methane sorption kinetics in coal samples obtained in laboratory conditions with the precise gravimetric sorption system IGA-001. The value of the coefficient was treated as an element tuning the model in such a way that the average relative error of the ex post was as small as possible. Model verification indicated the correctness of its ...


Digital Commons powered by bepress

必威体育官网 <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <蜘蛛词>| <文本链> <文本链> <文本链> <文本链> <文本链> <文本链>