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2020

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Articles 5701 - 5730 of 10651

Full-Text Articles in Engineering

Method Of Calendar Planning Of Construction Of The Complex At The Early Stage Of Design, M Mirakhmedov, M. Rasulmukhamedov, L.S. Yusupova May 2020

Method Of Calendar Planning Of Construction Of The Complex At The Early Stage Of Design, M Mirakhmedov, M. Rasulmukhamedov, L.S. Yusupova

Journal of Tashkent Institute of Railway Engineers

The construction schedule developed in the construction organization project does not meet the requirements of the reserve for construction, is not based on the choice of construction and technological schemes and the method of construction organization, therefore, it is not sufficiently reliable, the evidence base stored in the project archive is not confirmed by calculations and Therefore, it cannot be subjected to reliable examination. To eliminate this drawback, a technique is proposed that takes into account the lack of information. The methodology is based on the graphanalytic model of the flow organization of the construction of the complex, which allows …

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Adhesion Strength Of Modified Plaster Solutions For Restoration Of Rchitectural Monuments Of Bukhara, M.M. Vaxitov, A.A. Tulaganov, I.I. Tojiev May 2020

Adhesion Strength Of Modified Plaster Solutions For Restoration Of Rchitectural Monuments Of Bukhara, M.M. Vaxitov, A.A. Tulaganov, I.I. Tojiev

Journal of Tashkent Institute of Railway Engineers

In this work, the strength of historical mortars of brickwork of the Ismail Somoni mausoleum, the monument of architecture of the Kalyan minaret, the building of the Abdulazizkhan madrasah and the mausoleum of Abdukholik Gizhduvani were determined, and the compressive, tensile, bending and adhesion strengths of the developed modified gypsum mortars for restoration of the above architectural monuments were studied. It is shown that the adhesion strengths of modified gypsum mortars also meet the requirements of KMK 2-01-03-96.

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Formation Of A Calculation Model, Study Of Stress-Strain State And Vibrations Of Composite Shell Constructions From Composite Materials, A Abdusattarov, Z.Z. Ergashev, F.E. Abdukadirov May 2020

Formation Of A Calculation Model, Study Of Stress-Strain State And Vibrations Of Composite Shell Constructions From Composite Materials, A Abdusattarov, Z.Z. Ergashev, F.E. Abdukadirov

Journal of Tashkent Institute of Railway Engineers

The article gives geometric and physical relationships for shell and ring elements. At the same time, it is assumed that the physical properties of the material of the shell element are described by equations of a viscoelastic medium, taking into account the influence of damage accumulation. Using an approximate method, namely, the “freeze” procedure, a canonical system of equations is obtained - in the form of first-order differential equations with complex coefficients. To solve boundary value problems, the Godunov matrix sweep method is used.

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Research Deplanacion Cross-Section, Related To Them Size Under Torsion Fluctuation, Muradov Rustam Muradov, Abduvakhidov Mutakhkhirkhon Abduvakhidov May 2020

Research Deplanacion Cross-Section, Related To Them Size Under Torsion Fluctuation, Muradov Rustam Muradov, Abduvakhidov Mutakhkhirkhon Abduvakhidov

Journal of Tashkent Institute of Railway Engineers

In this work, the problem of torsional vibrations of rotating working bodies in the form of shafts is studied in case of violation of the assumption of flat sections under torsional strains associated with the peculiarities of torsion deformation of relatively short bodies. During torsional deformation caused by torsional vibrations, the initially rectilinear generators of the cylindrical surfaces of the shaft turn into screw curves of equal length. This causes the longitudinal displacements of their points and, as a result, the appearance of two types of deplanation of its cross sections. The first type of deplanation is associated with the …

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Technology For Preparing A Fiber Filler From Rice Straw And Analysis Of Its Interaction With A Modified Gypsum Matrix, Anvar Ishanovich Adilkhodjayev, B.G. Igamberdiev May 2020

Technology For Preparing A Fiber Filler From Rice Straw And Analysis Of Its Interaction With A Modified Gypsum Matrix, Anvar Ishanovich Adilkhodjayev, B.G. Igamberdiev

Journal of Tashkent Institute of Railway Engineers

The article presents research data on a composite material based on rice straw and construction gypsum. An overview of a method for preparing rice straw to increase the dispersion-reinforcing effect of the fiber filler is given. The results of the study of the synergistic effect of the “FremNanogis” modifying additive on the formation of the structure are presented.

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Calculation Of Operational Suitability And Reliability Of Structures, Nodira Ziyayevna Saatova, Abdurakhman Asimovich Ishankhodjaev May 2020

Calculation Of Operational Suitability And Reliability Of Structures, Nodira Ziyayevna Saatova, Abdurakhman Asimovich Ishankhodjaev

Journal of Tashkent Institute of Railway Engineers

With the acquisition of independence of our Republic in the system of transport communications, great importance was attached to the qualitative improvement of the design, construction, and operation of aboveground structures. Many tasks have been performed to increase the reliability and strength analysis of these bridges. Along with these, improving methods for calculating the resource of artificial structures in the system of transport communications are required. The Strategy for the Further Development of the Republic of Uzbekistan, including the following tasks: "... implementation of targeted programs for the development and modernization of road transport, engineering, communication, and social infrastructures, ...". …

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Estimation Of The Influence Of Cold Bridges On The Heat-Shielding Properties Of The External Walls Of Residential Buildings, Elena Vladimirovna Shchipacheva, Rakhmatullo Pirmatov, Makhina Turdalieva May 2020

Estimation Of The Influence Of Cold Bridges On The Heat-Shielding Properties Of The External Walls Of Residential Buildings, Elena Vladimirovna Shchipacheva, Rakhmatullo Pirmatov, Makhina Turdalieva

Journal of Tashkent Institute of Railway Engineers

Most of the existing multi-apartment residential buildings in Uzbekistan have external enclose structures with thermal performance that do not meet modern requirements. This is due to the design features of encloses in seismic areas of construction, necessarily including monolithic elements - anti-seismic belts, cores, frame elements and stiffeners. These elements, providing strength, rigidity and stability of structures, are at the same time powerful heat-conducting inclusions in warmer wall masonry materials. The article presents the results of theoretical and experimental studies on the estimation of the influence of cold bridges on the heat-shielding properties of external heat-technical inhomogeneous walls of civil …

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About The Influence Of Some Recipe-Technological Factors On The Properties Of Non-Autoclave Gas Concrete, Anvar Ishanovich Adilkhodjayev, S.S. Shaumarov May 2020

About The Influence Of Some Recipe-Technological Factors On The Properties Of Non-Autoclave Gas Concrete, Anvar Ishanovich Adilkhodjayev, S.S. Shaumarov

Journal of Tashkent Institute of Railway Engineers

This article presents the results of experimental studies on the production of cellular concrete with increased strength properties and improved indicators of the coefficient of structural quality. The use of the proposed composition will allow you to dispose of waste concrete and reduce production costs.

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Research Of The Possibility Of Using Waste Of Paint And Varnish Materials For Anti-Corrosion Protection Of Metal Parts Of Transport Equipment, Aida Barxanadjyan, Ravshan Hakimov, Botir Ibragimov May 2020

Research Of The Possibility Of Using Waste Of Paint And Varnish Materials For Anti-Corrosion Protection Of Metal Parts Of Transport Equipment, Aida Barxanadjyan, Ravshan Hakimov, Botir Ibragimov

Journal of Tashkent Institute of Railway Engineers

This work is devoted to the corrosion protection of metal parts of transport equipment. The purpose of this study is the use of waste paint and varnish materials (PVM) to obtain anti-corrosion coatings of metal parts. PVMwaste is the loss of paints obtained when painting automobiles. The epoxy polyurethane oligomer synthesized by us was used as a binder resin. During the research, the physicochemical properties of the waste were studied the components were selected to obtain anticorrosive mastic. The resulting mastic was tested in laboratory conditions in accordance with the standards for adhesion, chemical resistance, film strength in bending and …

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Production Of Building Materials Based On Waste Industry, Uchqun Abdullayevich Gaziyev May 2020

Production Of Building Materials Based On Waste Industry, Uchqun Abdullayevich Gaziyev

Journal of Tashkent Institute of Railway Engineers

The article describes the production technology of building materials based on industrial waste. Innovative technologies in the production of building materials, using industrial waste, are fully consistent with the research carried out at the Department of Technology of Building Materials, Products and Structures of the Tashkent Architectural and Construction Institute under the scientific supervision of the author of this article. Scientific developments in innovative technologies were carried out in several areas in the field of building materials and products. Based on the waste from the Angren coal deposit and local rocks, quartzite and dacitic porphyry, a gravel-like porous aggregate has …

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Technology Of Application Of Mechanical Joints Of Reinforcement In The Construction Of Towers Made Of Monolithic Reinforced Concrete, Kadir Karimovich Akhmedov May 2020

Technology Of Application Of Mechanical Joints Of Reinforcement In The Construction Of Towers Made Of Monolithic Reinforced Concrete, Kadir Karimovich Akhmedov

Journal of Tashkent Institute of Railway Engineers

Today, more than 3,000 skyscrapers have been built in the world, a third of which were built in China (including Hong Kong and Macao). The rest are located in the United States, Japan, the UAE and other countries, and every year more and more countries join the “sky club”. Uzbekistan also seeks to join this club and construction of the first NEST ONE skyscraper in Tashkent has begun. High-grade steel, concrete and a safe elevator are the true creators of the high-rise boom. In particular, reinforced concrete and the development of technologies for working with it contributed to the increase …

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Metal Wooden Spatial Rod Construction From Composition Wooden Elements, Narimonjon Sultanbaevich Tursunov, Sobirjon Juraevich Razzakov May 2020

Metal Wooden Spatial Rod Construction From Composition Wooden Elements, Narimonjon Sultanbaevich Tursunov, Sobirjon Juraevich Razzakov

Journal of Tashkent Institute of Railway Engineers

Metal wooden spatial core structure, including upper and lower grids, braces, combining the nodes of the upper and lower grids, and vertical strands, characterized in that, in order to ensure redistribution of forces and uniform load of structural elements and giving additional stiffness compressive composite small-sized boards of the upper belt and the lower metal belt with a special tensile nut to give the building a structural lift, are displaced in plan relative to each other by 45 °, while the braces in the nodes of the grids are located mutually perpendicular and in one direction they are made descending, …

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Structure Formation Of A Cement Stone With A Zeolite Containing Filler (Natrolite) And A Superplastificator, Anvar Ishanovich Adilkhodjayev, Ilkhom Abdullaevich Kadyrov, Kadyr Saparbaevich Umarov May 2020

Structure Formation Of A Cement Stone With A Zeolite Containing Filler (Natrolite) And A Superplastificator, Anvar Ishanovich Adilkhodjayev, Ilkhom Abdullaevich Kadyrov, Kadyr Saparbaevich Umarov

Journal of Tashkent Institute of Railway Engineers

The article presents the results of studies of the hydration process of the compositions "cement + zeolite-containing rock + superplasticizer" using the methods of IR spectrometry, differential thermal analysis. The scientific and practical significance of the work results for building materials science and the construction industry is to establish the effectiveness of the use of complex additives in the preparation of cement concrete.

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State And Prospects Of Production And Operation Of Synthetic Woven Belts (Table) For Load-Handling Devices (Hd) In The Republic Of Uzbekistan, Ibrohim Numanovich Abdullaev, Zhamoldin Dzhalalovich Akhmedov, Bakhodir Kushakovich Rakhmanov, Ruzikhon Toyirzhanovna Zhurabaeva May 2020

State And Prospects Of Production And Operation Of Synthetic Woven Belts (Table) For Load-Handling Devices (Hd) In The Republic Of Uzbekistan, Ibrohim Numanovich Abdullaev, Zhamoldin Dzhalalovich Akhmedov, Bakhodir Kushakovich Rakhmanov, Ruzikhon Toyirzhanovna Zhurabaeva

Journal of Tashkent Institute of Railway Engineers

In the world, the use of synthetic woven tapes (SWT) is increasing in various areas of life, including in construction. In particular, thanks to the development of production of high-strength synthetic fibers in such developed countries as Russia, USA, Germany, progress has been made in the creation and manufacture of heavy-duty lifting slings from STL, and on this basis to improve ergonomics and safety of installers, the safety of transported goods, the reduction of labor input and material on the load capacity.

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Investigation Of The Longitudinal Hijacking Force From Friction Braking, Makhamadjan Mirakhmedovich Mirakhmedov, Gali-Askar Rustamovich Khalfin May 2020

Investigation Of The Longitudinal Hijacking Force From Friction Braking, Makhamadjan Mirakhmedovich Mirakhmedov, Gali-Askar Rustamovich Khalfin

Journal of Tashkent Institute of Railway Engineers

On the elements of the longitudinal profile, when the train is decelerated from friction, an additional force of theft occurs. By modeling the braking process, the dependence of the driving forces on the braking friction is close to linear. The result of theft also depends on the power of the anti-theft system, namely, the force of pressing the fastening terminal to the rail, the weakness of which can subsequently affect the safety of trains and cause the track to be thrown out.

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Method For Evaluating The Residual Resource Of Long Designs, Sergey Vladimirovich Chizhov, Ulugbek Zabixullayevich Shermuxamedov, Sharofat Shavkatovna Kadirova May 2020

Method For Evaluating The Residual Resource Of Long Designs, Sergey Vladimirovich Chizhov, Ulugbek Zabixullayevich Shermuxamedov, Sharofat Shavkatovna Kadirova

Journal of Tashkent Institute of Railway Engineers

The article describes a method for calculating the safety of extended structures, in particular tunnels. The probabilistic approach to solving the problem is analyzed using the reliability of the structure with the probability of failure-free operation and assessment of the residual life of the structure. These characteristics make it possible to predict the residual life of the structure within a time value until the design has exhausted its ultimate state. An assessment of the operational reliability of the structure is carried out by measuring and establishing existing structural defects. Based on the data obtained, an analysis was carried out and …

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About The Technology Of Making Reinforced Concrete Sleep By Heating Concrete At Low Temperature, Turgunbaev Urinbek Jamolovich, Movluda Umirova May 2020

About The Technology Of Making Reinforced Concrete Sleep By Heating Concrete At Low Temperature, Turgunbaev Urinbek Jamolovich, Movluda Umirova

Journal of Tashkent Institute of Railway Engineers

The article discusses the properties of cement stone with the use of complex chemical additives to improve the technology for the production of sleepers from prestressed concrete. With the use of superplasticizer, the volume of intergranular space and, consequently, capillary porosity, which is a determining factor for both strength and frost resistance and corrosion resistance of concrete, are significantly reduced. Also, during thermo-wet processing, at a temperature of 40 ° C, there was no decrease in the strength of cement stone and sufficient strength at the initial stage of the curing period, 36 MPa with the addition of Glenium 27 …

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About Properties Of Modified Gypsum Compositions With Slag Filler And Chemical Additive, Jumagul Raximberdievna Turgunbaeva May 2020

About Properties Of Modified Gypsum Compositions With Slag Filler And Chemical Additive, Jumagul Raximberdievna Turgunbaeva

Journal of Tashkent Institute of Railway Engineers

The article presents the results of experiments to assess the effect of slag filler and chemical additives on the physical properties of the modified gypsum composition. In particular, it was shown that the water demand of building gypsum increases with an increase in the content of metallurgical slag in the composition. With its constant amount, an increase in the proportion of GLENIUM 27S superplasticizer additive does not affect the normal density value of the gypsum dough. This suggests that the presence of a plasticizing effect from the introduction of superplasticizer GLENIUM 27S. In addition, filling gypsum with metallurgical slag with …

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Experimental Research Methodology For The Crack Resistance Of Large-Panel Buildings In Seismic Areas, Nigmat Baxramovich Shaumarov, Ulugbek Xakimovich Abdullayev May 2020

Experimental Research Methodology For The Crack Resistance Of Large-Panel Buildings In Seismic Areas, Nigmat Baxramovich Shaumarov, Ulugbek Xakimovich Abdullayev

Journal of Tashkent Institute of Railway Engineers

The experience of the Tashkent, Spitak, Kyrgyz and Kamchatka earthquakes of recent years has led to the conclusion that there is a sufficient good seismic resistance of large-panel buildings with a narrow step of transverse load-bearing walls. One of the distinguishing structural features of buildings is considered to be the overlapping of individual multi-hollow panels with their support on special cantilevered outlets along the lateral surfaces of the transverse walls. Elements of the outer walls were made of expanded clay concrete with a compressive strength of about 200 kg / cm2. All structures were reinforced with flat welded frames made …

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Investigation Of Way Embankment Stability On Movement Of High Speed Trains, Mirzakhid Khamitovich Miralimov, Shakhboz Ulugbekovich Normurodov May 2020

Investigation Of Way Embankment Stability On Movement Of High Speed Trains, Mirzakhid Khamitovich Miralimov, Shakhboz Ulugbekovich Normurodov

Journal of Tashkent Institute of Railway Engineers

In this paper is considered the problem related with a stressed state of railway embankments taking into account of dynamic loadings from high-speed trains. In the offered technical method is giving wave nature transmissions of dynamic loading from the passenger trains and their interaction of soil layers with various parameters. The design procedure gives a clear physical and mathematical pattern, where all formulas are in detail shown and simple for understanding. Calculation is conducted numerically in two stages. Considering from classical principles of structural mechanics, the first calculation stage of the railway structures includes deformation of the railway sleepers taking …

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Research Of Properties Of Composite Elastomeric Material Filled With Montmorillonite Of Karakalpakstan With Nanoparticles, Bakhadir Bakhramovich Kakharov, Akhmadjan Ibadullaev, Elmira Ubaydullayevna Teshabaeva, Marziya Begdullayevna Muftullayeva May 2020

Research Of Properties Of Composite Elastomeric Material Filled With Montmorillonite Of Karakalpakstan With Nanoparticles, Bakhadir Bakhramovich Kakharov, Akhmadjan Ibadullaev, Elmira Ubaydullayevna Teshabaeva, Marziya Begdullayevna Muftullayeva

Journal of Tashkent Institute of Railway Engineers

The paper presents the results of studies on the effect of montmorillonite of Karakalpakstan with nanoparticles on the specific properties of composite elastomeric materials based on a mixture of rubbers SKMS-30 ARKM-15 (70%) and SKN-26 (30%). It was found that with an increase in the filler content in rubber, the recoverability of the rubber compound after deformation is significantly reduced. Moreover, the ability of the system to accumulate the energy of elastic deformation, i.e. the swelling of the extrudate (Re), largely depends on the specific geometric surface (Ssp) of montmorillonite of Karakalpakstan. Studies of the properties of rubbers showed that …

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Innovative Technologies For Formless Forming Of Multi-Hollow Floor Slabs, Anvar Ishanovich Adilkhodjayev, V.M. Tsoy, K Umarov May 2020

Innovative Technologies For Formless Forming Of Multi-Hollow Floor Slabs, Anvar Ishanovich Adilkhodjayev, V.M. Tsoy, K Umarov

Journal of Tashkent Institute of Railway Engineers

the article discusses the technology of non-formwork molding and reinforcement of hollow-core floor slabs. Optimal methods of concrete mixture compaction and reduction of cement consumption without loss of the required concrete strength are analyzed. The use of floor slabs developed using no-form molding technology in conditions of increased seismic activity.

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About The Influence Of The Organosilicon Hydrophobizer "Gidrofob" On The Properties Of Non-Autoclave Gas Concrete, V.M. Tsoy, S. Hodjayev May 2020

About The Influence Of The Organosilicon Hydrophobizer "Gidrofob" On The Properties Of Non-Autoclave Gas Concrete, V.M. Tsoy, S. Hodjayev

Journal of Tashkent Institute of Railway Engineers

The article examines the effect of hydrophobizing additives on the normal density and setting time of the cement paste and the strength of the cement stone. We used an organosilicon additive - "Hydrophobe" as a water-repellent additive. As a result of research, it was found that the introduction of a water repellent agent, depending on its dosage, leads to a significant increase in the setting time and insignificantly affects the strength

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Cet 322-450: Construction Regulations And Standards, John Wiggins May 2020

Cet 322-450: Construction Regulations And Standards, John Wiggins

School of Applied Engineering and Technology Syllabi

No abstract provided.

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Design And Research On Semi-Physical Simulation Test System Of Aero Engine, Jingfeng Shen, Chulei Li, Dianliang Wu, Jiaxin Zhang May 2020

Design And Research On Semi-Physical Simulation Test System Of Aero Engine, Jingfeng Shen, Chulei Li, Dianliang Wu, Jiaxin Zhang

Journal of System Simulation

Abstract: Aiming at the high danger and difficulty of the operation in the aero-engine test, a semi-physical simulation test system that integrates the functions of the test-run operation training, process analysis, simulation of the typical engine performance fault is proposed. Based on the fast response, accurate calculation and high human operation simulation of the engine digital model, the key problems of the research and implementation, such as the structural design of the distributed semi-physical simulation system, visualization of the calculation model of the engine subsystem and real-time visualization of the aero-engine test data displaying in the three-dimensional cave automatic …

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Simulation Of Human Body Temperature Distribution Based On New Solution For Heat Conduction Differential Equation, Sina Dang, Hongjun Xue, Xiaoyan Zhang, Chengwen Zhong, Caiyong Tao May 2020

Simulation Of Human Body Temperature Distribution Based On New Solution For Heat Conduction Differential Equation, Sina Dang, Hongjun Xue, Xiaoyan Zhang, Chengwen Zhong, Caiyong Tao

Journal of System Simulation

Abstract: In the traditional rectangular coordinate system, the human body characteristics can not match the differential equation. This leads to the low accuracy of the simulation results. Based on the geometric characteristics of the elliptic cylinder, the differential equation of the heat conduction is transformed from the rectangular coordinate system to the elliptic one, and the finite volume method of the alternating direction full implicit scheme pair is adopted. The improved heat conduction differential equation is applied to the simulation of the human body temperature. The simulation results, compared with the calculated values of the traditional differential equation …

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Hollow-Core Photonic Crystal Fiber Mach–Zehnder Interferometer For Gas Sensing, Kaveh Nazeri, Farid Ahmed, Vahid Ahsani, Hang-Eun Joe, Colin Bradley, Ehsan Toyserkani, Martin B. G. Jun May 2020

Hollow-Core Photonic Crystal Fiber Mach–Zehnder Interferometer For Gas Sensing, Kaveh Nazeri, Farid Ahmed, Vahid Ahsani, Hang-Eun Joe, Colin Bradley, Ehsan Toyserkani, Martin B. G. Jun

Manufacturing & Industrial Engineering Faculty Publications

A novel and compact interferometric refractive index (RI) point sensor is developed using hollow-core photonic crystal fiber (HC-PCF) and experimentally demonstrated for high sensitivity detection and measurement of pure gases. To construct the device, the sensing element fiber (HC-PCF) was placed between two single-mode fibers with airgaps at each side. Great measurement repeatability was shown in the cyclic test for the detection of various gases. The RI sensitivity of 4629 nm/RIU was demonstrated in the RI range of 1.0000347–1.000436 for the sensor with an HC-PCF length of 3.3 mm. The sensitivity of the proposed Mach–Zehnder interferometer (MZI) sensor increases when …

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The Role Of Gene Transcription And Inflammatory Cytokines In Bone Fracture Repair, Brandon Alan Coates May 2020

The Role Of Gene Transcription And Inflammatory Cytokines In Bone Fracture Repair, Brandon Alan Coates

McKelvey School of Engineering Graduate Student Theses & Dissertations

In most instances, the skeleton has a remarkable capacity for repair following injury. However, in 5 to 10% of patients, fractures fail to properly heal resulting in non-union. A need exists for a more comprehensive understanding of the complex biology of fracture repair, which involves the coordinated work of many cell types including osteoblasts, osteoclasts, and immune cells. Depending on the extent of injury, fractures will heal through either intramembranous bone formation, involving the direct formation of bone callus, or endochondral bone formation, featuring a cartilage intermediary prior to bone callus formation. Both processes begin with inflammation, which sets the …

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Development Of Novel Instrumentation And Methods To Investigate The Composition And Phase Partitioning Of Semivolatile And Intermediately Volatile Organic Compounds In Atmospheric Organic Aerosol, Claire Fortenberry May 2020

Development Of Novel Instrumentation And Methods To Investigate The Composition And Phase Partitioning Of Semivolatile And Intermediately Volatile Organic Compounds In Atmospheric Organic Aerosol, Claire Fortenberry

McKelvey School of Engineering Graduate Student Theses & Dissertations

Atmospheric particulate matter (PM) is ubiquitous in both indoor and outdoor air and is generally detrimental to human health. PM composed of particles with aerodynamic diameters less than 2.5 um (PM2.5) are related to adverse health outcomes including heart disease and respiratory disease. Fundamentally, particle physical properties such as size and hygroscopicity are dictated by chemical composition, which can be highly complex, particularly for organic aerosol (OA). In both outdoor and indoor air, OA is composed substantially of intermediately volatile and semivolatile organic compounds (I/SVOCs), which exist in both gas and particle phases under typical atmospheric conditions. The distribution of …

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Nucleation Dynamics For Water Condensation On Hydrophobic Surfaces In The Presence Of Non-Condensable Gases, Xinyu Jiang May 2020

Nucleation Dynamics For Water Condensation On Hydrophobic Surfaces In The Presence Of Non-Condensable Gases, Xinyu Jiang

McKelvey School of Engineering Graduate Student Theses & Dissertations

The density and rate of nucleation (here-in called nucleation density rate) significantly influences the heat transfer performance during dropwise condensation, as more than 70% of the total heat transfer happen for droplets smaller than 10 μm. Based on the classical nucleation theory, supersaturation strongly influences nucleation dynamics. However, the presence of non-condensable gas can strongly reduce the nucleation density rate by forming a vapor-depleted gas diffusion layer. Therefore, this work studied the relationship between nucleation density rate and supersaturation ratio during dropwise condensation on subcooled smooth hydrophobic surfaces with the presence of non-condensable gases in a custom-built condensation chamber. High-speed …

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