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2021

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Articles 451 - 480 of 708

Full-Text Articles in Materials Science and Engineering

Initial Assessment Of Liquefied Scrap Tire Concrete, Abdulkareem Kuaryouti, Christopher D. Eamon Feb 2021

Initial Assessment Of Liquefied Scrap Tire Concrete, Abdulkareem Kuaryouti, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

A new approach to incorporate scrap tire material into concrete was investigated, where two reclaimed waste tire components, carbon black and fuel oil, were used to replace a portion of water. The effect of “liquid tire” content to water ratios from 5-40% on an otherwise typical concrete mix were assessed, where compressive and flexural strength, flexural toughness, modulus of elasticity, and several fresh concrete properties were determined. Results were compared to typically expected results of traditional shredded tire mixes with equivalent tire content. It was found that the liquid tire mixes experienced significantly less losses of compressive strength and workability …

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Development Of Preparations Based On Local Components For Dust Suppression On Quarry Roads, Olikulov Fakhriyor, Mukhiddinov Bakhоdir, Vapoev Khusniddin, Zhurayev Shokhruh Feb 2021

Development Of Preparations Based On Local Components For Dust Suppression On Quarry Roads, Olikulov Fakhriyor, Mukhiddinov Bakhоdir, Vapoev Khusniddin, Zhurayev Shokhruh

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the work is to develop dust-collecting preparations based on local raw materials for the suppression of man-made dust formed on quarry paths. For this purpose, 4 types of the drug were created in the laboratory on the basis of domestic raw materials for dust suppression. The dependence of the viscosity and density of the created preparations on the concentration of components and temperature is studied. For the preparation of the solution of the created drug, a semi-industrial installation is created, which presents the general view and the process of preparing the solution. The spray of the prepared …

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Synthesis And Research Of Chelate Forming Sorbent Based On Carbamide, Formaldehyde, Ditizone, Chorieva Nigora, Ermuratova Nilufar, Turaev Khayit, Kasimov Sherzod Feb 2021

Synthesis And Research Of Chelate Forming Sorbent Based On Carbamide, Formaldehyde, Ditizone, Chorieva Nigora, Ermuratova Nilufar, Turaev Khayit, Kasimov Sherzod

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this study is the synthesis and study of a chelating sorbent for the extraction of ions of non-ferrous and noble metals. To achieve this goal, a sulfur-containing chelating sorbent based on carbamide, formaldehyde, and dithizone was synthesized and studied. The optimal conditions for the synthesis of the sorbent have been determined and studies have been carried out on the influence of the molar ratios of the starting materials on the composition, and physicochemical properties of the synthesized sorbent. The optimum temperature of polycondensation was taken as 90 °C, the reaction time is 2.5-3 hours, as a result, …

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Synthesis And Spectroscopic Study Of Complex Compounds Of Mn(Ii), Co(Ii), Ni(Ii), Cu(Ii) And Zn(Ii) Acetates With 2-Aminobenzimidazole, Gapurova Lobar, Kadirova Shakhnoza, Rakhmonоva Dilnoza, Olimova Manzura Feb 2021

Synthesis And Spectroscopic Study Of Complex Compounds Of Mn(Ii), Co(Ii), Ni(Ii), Cu(Ii) And Zn(Ii) Acetates With 2-Aminobenzimidazole, Gapurova Lobar, Kadirova Shakhnoza, Rakhmonоva Dilnoza, Olimova Manzura

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the work is to develop a synthesis procedure and obtain new complex compounds of transition metal acetates with 2-aminobenzimidazole (L), to study the composition and structure of the synthesized compounds by elemental, thermal, X-ray phase analysis and IR spectroscopy. A procedure for the synthesis of new complex compounds of Mn(II), Cо(II), Ni(II), Cu(II) and Zn acetates with 2-aminobenzimidazole was developed and the composition and structure of the synthesized complex compounds were studied using modern physicochemical methods. Coordination competing donor centers, electronic and geometric structures of the ligand molecule were studied on the basis of a quantum-chemical calculation …

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Effect Of Light On The Resistance Of Bi/Pb Superconductors Synthesized By Solar Energy, Gulamova Dilbara, Echonkulov Elyor, Jalilov Dilshod, Bobokulov Sirojiddin Feb 2021

Effect Of Light On The Resistance Of Bi/Pb Superconductors Synthesized By Solar Energy, Gulamova Dilbara, Echonkulov Elyor, Jalilov Dilshod, Bobokulov Sirojiddin

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the work is to expand the capabilities of solar technologies and areas of practical use of superconductors. The effect of white light on the interaction of superconducting ceramics with a magnet at room temperature was investigated. It has been established that the magnet is “ejected” by ceramic samples of nominal Bi1,7Pb0,3Sr2Ca(n-1)CunOy, (n = 5-20) under the influence of white light and there is no effect in the dark. The resistance of Bi/Pb superconducting ceramics is reduced by exposure to light compared to resistance in the dark. The resistance of ceramics containing higher superconducting higher superconducting phases Tc …

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Spectrophotometric Color Determination Of Ceramic Pigments For Construction Ceramics And Regional Innovation System, Kadyrova Dilorom, Mansurov Yulbarskhon, Abdusattarov Shakirjan Feb 2021

Spectrophotometric Color Determination Of Ceramic Pigments For Construction Ceramics And Regional Innovation System, Kadyrova Dilorom, Mansurov Yulbarskhon, Abdusattarov Shakirjan

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work is the spectrophotometric determination of the color of ceramic pigments for the development of technology for the production of high-quality ceramic paints of a wide color palette for decorating building ceramics, porcelain and faience products. In this regard, using the principles of heterovalent isomorphic substitution of atoms in crystals, the compositions of ceramic pigments were designed on the basis of the anorthite derivatives containing transition elements with the general formula Са1-хMexAl2+xSi2-xО8, where calcium and silicon ions were replaced by aluminum and transition element, Ме – Cо, Ni, Fe, Cr. The color characteristics were taken on …

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Characterization, Immobilization, And Polymer Related Applications Of Watermelon Seed Powder, A Practical Source Of Urease Enzyme, Anthony Quan Quoc Mai Feb 2021

Characterization, Immobilization, And Polymer Related Applications Of Watermelon Seed Powder, A Practical Source Of Urease Enzyme, Anthony Quan Quoc Mai

LSU Doctoral Dissertations

Urease enzyme was crystallized almost a century ago, and to this day its intrinsic stability is not ideal for everyday applications. This work introduces a new process by which a naturally encapsulated material, watermelon seed powder (WMSP), is characterized for its stability and activity. WMSP enzymatic activity has been measured for over a year at various storage conditions—exposed to ambient atmosphere for a year, WMSP retained above 90% activity. In aqueous conditions, the enzyme maintained above 60% activity after two months; with the addition of a preservative that number stays at about 90%. There is a pH shift of the …

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Fluid Separation And Network Deformation In Wetting Of Soft And Swollen Surfaces, Zhuoyun Cai, Artem Skabeev, Svetlana Morozova, Jonathan T. Pham Feb 2021

Fluid Separation And Network Deformation In Wetting Of Soft And Swollen Surfaces, Zhuoyun Cai, Artem Skabeev, Svetlana Morozova, Jonathan T. Pham

Chemical and Materials Engineering Faculty Publications

When a water drop is placed onto a soft polymer network, a wetting ridge develops at the drop periphery. The height of this wetting ridge is typically governed by the drop surface tension balanced by elastic restoring forces of the polymer network. However, the situation is more complex when the network is swollen with fluid, because the fluid may separate from the network at the contact line. Here we study the fluid separation and network deformation at the contact line of a soft polydimethylsiloxane (PDMS) network, swollen with silicone oil. By controlling both the degrees of crosslinking and swelling, we …

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Scale Model Test To Estimate Thermal Damage By Fire In Aircraft Cargo, Jian Gao, Tsuneyoshi Matsuoka, Yuji Nakamura Feb 2021

Scale Model Test To Estimate Thermal Damage By Fire In Aircraft Cargo, Jian Gao, Tsuneyoshi Matsuoka, Yuji Nakamura

Progress in Scale Modeling, an International Journal

The Federal Aviation Administration (FAA) requires fire detectors to alarm within one minute of the start of a fire in cargo compartments of airplanes. To determine whether such alarm timing works, investigations of the thermal damage to ceilings and other structures during the early stage of a fire were accomplished to demonstrate compliance with these FAA regulations. The objective was to test the feasibility of predicting convective heat transfer in early stage of a cargo compartment fire by conducting reduced scale (lab scale) experiments. First, the scaling laws was derived and validated. Then, full-scale and half-scale experiments were performed with …

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Under Pressure: Hydrogel Swelling In A Granular Medium, Jean François Louf, Nancy B. Lu, Margaret G. O'Connell, H. Jeremy Cho, Sujit S. Datta Feb 2021

Under Pressure: Hydrogel Swelling In A Granular Medium, Jean François Louf, Nancy B. Lu, Margaret G. O'Connell, H. Jeremy Cho, Sujit S. Datta

Mechanical Engineering Faculty Research

Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). Hydrogels hold promise in agriculture as reservoirs of water in dry soil, potentially alleviating the burden of irrigation. However, confinement in soil can markedly reduce the ability of hydrogels to absorb water and swell, limiting their widespread adoption. Unfortunately, the underlying reason remains unknown. By directly visualizing the swelling of hydrogels confined in three-dimensional granular media, we demonstrate that the extent of hydrogel swelling is …

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International Journal Of Electrical And Computer Engineering, Fred Lacy Feb 2021

International Journal Of Electrical And Computer Engineering, Fred Lacy

Faculty Publications

A superconductor has the ability to conduct electricity perfectly and exclude magnetic fields from its interior. In order to understand electromagnetic characteristics of superconductors, their material properties need to be examined. To facilitate this understanding, a theoretical model based on concepts of electromagnetics is presented to explain the electrical and magnetic properties of superconductors. The permittivity response is the key aspect of the model and it describes the electrical resistance response and why it vanishes at the material’s critical temperature. The model also explains the behavior of magnetic fields and why they cannot exist inside superconducting materials. The theoretical concepts …

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Discrete Element Modeling Of Hydrogel Extrusion, Rohit Boddu Feb 2021

Discrete Element Modeling Of Hydrogel Extrusion, Rohit Boddu

Theses and Dissertations

Hydrogels are widely used in extrusion bioprinting as bioinks. Understanding how the hydrogel microstructure affects the bioprinting process aids researchers in predicting the behavior of biological components. Current experimental tools are unable to measure internal forces and microstructure variations during the bioprinting process. In this work, discrete element modeling was used to study the internal interactions and the elastic deformation of the molecular chains within hydrogel networks during the extrusion process. Two-dimensional models of hydrogel extrusions were created in Particle Flow Code (PFC; Itasca Co., Minneapolis, MN). For our model's calibration, hydrogel compression testing was used in which a cluster …

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Absorption Of Nitrogen During Pulsed Wave L-Pbf Of 17-4 Ph Steel, Ben Brown, Joseph William Newkirk, Frank W. Liou Feb 2021

Absorption Of Nitrogen During Pulsed Wave L-Pbf Of 17-4 Ph Steel, Ben Brown, Joseph William Newkirk, Frank W. Liou

Materials Science and Engineering Faculty Research & Creative Works

In the fabrication of 17-4 PH by laser powder bed fusion (L-PBF) the well-documented occurrence of large amounts of retained austenite can be attributed to an elevated concentration of nitrogen present in the material. While the effects of continuous wave (CW) laser processing on in-situ nitrogen absorption characteristics have been evaluated, power modulated pulsed wave (PW) laser processing effects have not. In this study the effects of PW L-PBF processing of 17-4 PH on nitrogen absorption, phase composition, and mechanical performance are explored using commercially available PW L-PBF equipment and compared to samples produced by CW L-PBF. PW L-PBF samples …

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Thermodynamic Prediction And Experimental Verification Of Multiphase Composition Of Scale Formed On Reheated Alloy Steels, Richard Osei, Semen Naumovich Lekakh, Ronald O'Malley Feb 2021

Thermodynamic Prediction And Experimental Verification Of Multiphase Composition Of Scale Formed On Reheated Alloy Steels, Richard Osei, Semen Naumovich Lekakh, Ronald O'Malley

Materials Science and Engineering Faculty Research & Creative Works

The structure, phase, and composition of scale formed on a continuously cast steel slab during reheating depend on intrinsic factors (steel chemistry, microstructure, and as-cast surface condition) and extrinsic parameters (temperature, time, composition, and velocity of combustion gas atmosphere). The scale that forms on a slab normally has several layers with differing compositions and phases and knowledge of this scale structure is important in subsequent descaling and hot rolling processing steps. Formation of multiphase scale structures on steel during high temperature oxidation in reheat furnace proceeds according to a local thermodynamic equilibrium, while thickness of layers depends on kinetic conditions …

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Impact Of Grain Orientation And Phase On Volta Potential Differences In An Additively Manufactured Titanium Alloy, Jake T. Benzing, Olivia O. Maryon, Nik Hrabe, Paul H. Davis, Michael F. Hurley, Frank W. Delrio Feb 2021

Impact Of Grain Orientation And Phase On Volta Potential Differences In An Additively Manufactured Titanium Alloy, Jake T. Benzing, Olivia O. Maryon, Nik Hrabe, Paul H. Davis, Michael F. Hurley, Frank W. Delrio

Materials Science and Engineering Faculty Publications and Presentations

This work introduces a method for co-localized multi-modal imaging of sub-μm features in an additively manufactured (AM) titanium alloy. Ti-6Al-4V parts manufactured by electron beam melting powder bed fusion were subjected to hot isostatic pressing to seal internal porosity and machined to remove contour–hatch interfaces. Electron microscopy and atomic force microscopy-based techniques (electron backscatter diffraction and scanning Kelvin probe force microscopy) were used to measure and categorize the effects of crystallographic texture, misorientation, and phase content on the relative differences in the Volta potential of α-Ti and β-Ti phases. Given the tunability of additive manufacturing processes, …

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Structural Identification And Damage Detection In Bridges Using Wave Method And Uniform Shear Beam Models: A Feasibility Study, Mehran Rahmani, Manan Naik Feb 2021

Structural Identification And Damage Detection In Bridges Using Wave Method And Uniform Shear Beam Models: A Feasibility Study, Mehran Rahmani, Manan Naik

Mineta Transportation Institute

This report presents a wave method to be used for the structural identification and damage detection of structural components in bridges, e.g., bridge piers. This method has proven to be promising when applied to real structures and large amplitude responses in buildings (e.g., mid-rise and high-rise buildings). This study is the first application of the method to damaged bridge structures. The bridge identification was performed using wave propagation in a simple uniform shear beam model. The method identifies a wave velocity for the structure by fitting an equivalent uniform shear beam model to the impulse response functions of the recorded …

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The Hot Cracking Susceptibility Subjected The Laser Beam Oscillation Welding On 6xxx Aluminum Alloy With A Partial Penetration Joint, Minjung Kang, Jason Cheon, Dong Hyuck Kam, Cheolhee Kim Feb 2021

The Hot Cracking Susceptibility Subjected The Laser Beam Oscillation Welding On 6xxx Aluminum Alloy With A Partial Penetration Joint, Minjung Kang, Jason Cheon, Dong Hyuck Kam, Cheolhee Kim

Mechanical and Materials Engineering Faculty Publications and Presentations

A laser beam oscillation method using Galvano mirrors, which allows wide weld beads and controls thermal stress distribution, was suggested to suppress the formation of solidification cracks in laser welds. In order to understand the solidification cracking behavior in relation to the bead shape, laser beam oscillation welding was performed under various oscillation widths and frequency conditions. To evaluate the effect of the oscillation parameter on solidification cracking susceptibility, a regression analysis based on the shape of the bead was performed. Stress distribution generated during the laser beam oscillation welding process was also analyzed using finite element modeling simulation. From …

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Substituent Effects On The Solubility And Electronic Properties Of The Cyanine Dye Cy5: Density Functional And Time-Dependent Density Functional Theory Calculations, Austin Biaggne, William B. Knowlton, Bernard Yurke, Jeunghoon Lee, Lan Li Feb 2021

Substituent Effects On The Solubility And Electronic Properties Of The Cyanine Dye Cy5: Density Functional And Time-Dependent Density Functional Theory Calculations, Austin Biaggne, William B. Knowlton, Bernard Yurke, Jeunghoon Lee, Lan Li

Materials Science and Engineering Faculty Publications and Presentations

The aggregation ability and exciton dynamics of dyes are largely affected by properties of the dye monomers. To facilitate aggregation and improve excitonic function, dyes can be engineered with substituents to exhibit optimal key properties, such as hydrophobicity, static dipole moment differences, and transition dipole moments. To determine how electron donating (D) and electron withdrawing (W) substituents impact the solvation, static dipole moments, and transition dipole moments of the pentamethine indocyanine dye Cy5, density functional theory (DFT) and time-dependent (TD-) DFT calculations were performed. The inclusion of substituents had large effects on the solvation energy of Cy5, with pairs of …

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Economics Of Grid-Tied Solar Photovoltaic Systems Coupled To Heat Pumps: The Case Of Northern Climates Of The U.S. And Canada, Joshua M. Pearce, Nelson Sommerfeldt Feb 2021

Economics Of Grid-Tied Solar Photovoltaic Systems Coupled To Heat Pumps: The Case Of Northern Climates Of The U.S. And Canada, Joshua M. Pearce, Nelson Sommerfeldt

Michigan Tech Publications, Part 1

Solar photovoltaic (PV) technology is now a profitable method to decarbonize the grid, but if catastrophic climate change is to be avoided, emissions from transportation and heating must also decarbonize. One approach to renewable heating is leveraging improvements in PV with heat pumps (HPs). To determine the potential for PV+HP systems in northern areas of North America, this study performs numerical simulations and economic analysis using the same loads and climate, but with local electricity and natural gas rates for Sault Ste. Marie, in both Canada and U.S. Ground-mounted, fixed-tilt, grid-tied PV systems are sized to match 100% of electric …

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Photoinduced Trapping Of Charge At Sulfur Vacancies And Copper Ions In Photorefractive Sn2P2S6 Crystals, Timothy D. Gustafson, Eric M. Golden, Elizabeth M. Scherrer, Nancy C. Giles, A. A. Grabar, Sergey A. Basun, Jonathan E. Slagle [*], Larry E. Halliburton Feb 2021

Photoinduced Trapping Of Charge At Sulfur Vacancies And Copper Ions In Photorefractive Sn2P2S6 Crystals, Timothy D. Gustafson, Eric M. Golden, Elizabeth M. Scherrer, Nancy C. Giles, A. A. Grabar, Sergey A. Basun, Jonathan E. Slagle [*], Larry E. Halliburton

Faculty Publications

Electron paramagnetic resonance (EPR) is used to monitor photoinduced changes in the charge states of sulfur vacancies and Cu ions in tin hypothiodiphosphate. A Sn2P2S6 crystal containing Cu+ (3d10) ions at Sn2+ sites was grown by the chemical vapor transport method. Doubly ionized sulfur vacancies (V2+S) are also present in the as-grown crystal (where they serve as charge compensators for the Cu+ ions). For temperatures below 70 K, exposure to 532 or 633 nm laser light produces stable Cu2+ (3d9) ions, as electrons move from Cu+ ions to …

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Nanoengineered Materials For Energy Conversion & Storage Applications: A Density Functional Theory Study, Ahmed Biby Jan 2021

Nanoengineered Materials For Energy Conversion & Storage Applications: A Density Functional Theory Study, Ahmed Biby

Theses and Dissertations

The conventional approach for the development of novel materials has become long relative to the desired product development cycle. Thus, the sluggish pace of the development of materials within the conventional approach hinders the rapid transformation of the scientific outcomes into useful technological products. To this end, the field of hierarchical materials informatics evolved to bridge this gap. In this field, the multiscale material internal structure is considered the starting point and the core of this approach. This being said, the density functional theory (DFT) was used to generate useful materials data for the advancement of the hierarchical materials data-bases …

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Assessment Of Heavy Metal Concentration In Soils Around Geita The Gold Mine, Tanzania, Mariam G. Mgendi, Mkabwa L. K Manoko, W.J.S. Mwegoha, C. Southway C. Southway Jan 2021

Assessment Of Heavy Metal Concentration In Soils Around Geita The Gold Mine, Tanzania, Mariam G. Mgendi, Mkabwa L. K Manoko, W.J.S. Mwegoha, C. Southway C. Southway

Journal of Humanities and Social Sciences

Health issues related to gold mining cannot be underestimated. Gold mining produce acid mine drainage (AMD), which in turn releases heavy metals into the nearby environment, hence causing environmental pollution. Heavy metals are naturally very toxic, thus pose a great health concern especially when their concentration exceeds the recommended permissible limits. In this study, concentrations of five heavy metals—including Pb, Ni, Cr, Cu and Zn—were assessed in the soil around Geita Gold Mine (GGM). A total of 17 sampling sites were established from which the soil samples were collected at 0-15cm and 15-30cm soil depth. The concentration of both total …

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Multifunctional Polydopamine Nanomaterials For Biomedical And Environmental Applications, Hamed Gholami Derami Jan 2021

Multifunctional Polydopamine Nanomaterials For Biomedical And Environmental Applications, Hamed Gholami Derami

McKelvey School of Engineering Graduate Student Theses & Dissertations

Polydopamine (PDA), a synthetic and organic material, has emerged as a promising materialplatform for various applications in energy, environmental, and biomedical fields. PDA, formed by self-polymerization of dopamine, is rich in catechol and amine groups, which facilitate covalent conjugation and/or other non-covalent interactions with organic and inorganic materials. It is highly biocompatible, biodegradable, has broadband light absorption spectrum and excellent light-to-heat conversion efficiency. Also, it is easy to synthesize and functionalize. The combination of excellent characteristics of polydopamine-based nanomaterials, make them a promising adsorbent agent for environmental wastewater treatment and photothermal agent for biomedical applications. In the first half of …

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Mechanical Strength Of Germanium Doped Low Oxygen Concentration Czochralski Silicon And The Effect Of Oxygen On Nitrogen Dissociation In Silicon, Junnan Wu Jan 2021

Mechanical Strength Of Germanium Doped Low Oxygen Concentration Czochralski Silicon And The Effect Of Oxygen On Nitrogen Dissociation In Silicon, Junnan Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

During the Czochralski growth of silicon, it is inevitable for oxygen to be incorporated into the silicon crystal from the quartz crucible. Interstitial oxygen improves the mechanical strength of silicon by pinning and locking dislocations, but also generates thermal donors during device processes, shifting the electrical resistivity. For silicon wafers used in radio frequency (RF) applications, it is important to ensure the high resistivity of the substrates for good RF characteristics. Therefore, the oxygen level in these high resistivity silicon wafers is kept very low (< 2.5 × 1017 atoms/cm3) by carefully controlling the Czochralski growth conditions, in order to reduce the thermal donor concentration to an acceptable level. Silicon on insulator (SOI) substrates made from high resistivity wafers have been widely used for RF applications. SOI manufacturing includes multiple high temperature thermal cycles (1000 – 1100 °C), during which the high resistivity wafers are prone to slip and warpage. Therefore, it is technologically important to recover some of the lost mechanical strength due to the lack of oxygen by introducing electrically inactive impurities to suppress the dislocation generation and mobility in silicon. Germanium (Ge) as an isovalent impurity is 4% larger in size and forms a solid solution with silicon in the entire concentration range. Previous works have shown Ge doping at high concentrations above 6 × 1019 atoms/cm3 increased mechanical strength of silicon with high oxygen concentration (~ 1 × 1018 atoms/cm3). In this work, we explore the effect of Ge doping (7 - 9 × 1019 atoms/cm3) on the mechanical strength of low oxygen concentration (< 2 × 1017 atoms/cm3) silicon, where the oxygen associated dislocation locking and pinning are very low. A mechanical bending test was used to study the average dislocation migration velocity and the critical shear stress of dislocations motion at 600 – 750 °C for Ge doped, nitrogen doped, and undoped low oxygen samples, as well as nitrogen doped float-zone and un-doped high oxygen concentration samples. Next, we fabricated SOI substrates using these high resistivity wafers and compared their slip generation rates and the slip-free epitaxial grow temperature windows after the high temperature thermal cycles (> 1000 °C). Our results indicate at lower temperature Ge doesn’t affect the dislocation mobility …

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Nanoscale Enhancement Of Photosensitized Radionuclide Stimulated Therapy, Daniel Douglas Lane Jan 2021

Nanoscale Enhancement Of Photosensitized Radionuclide Stimulated Therapy, Daniel Douglas Lane

McKelvey School of Engineering Graduate Student Theses & Dissertations

Photodynamic therapy (PDT) provides efficient tumor killing through the generation of reactive oxygen species (ROS) from the optical excitation of a photosensitizer (PS). Furthermore, this mechanism is highly immune stimulating, providing systemic tumor immunity with a reduction in metastasis. However, these materials had previously been limited by their dependence upon external light sources, allowing treatment of only laser-accessible malignancy. With the recent development of photosensitized radiation stimulated therapy (PRaST) this depth dependence is broken through co-localization of radionuclides and semiconducting photosensitizers. This dissertation focuses on the enhancement of titanium dioxide (TiO2) based PRaST agents through understanding of TiO2 material parameters …

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Flexible Nanopaper Composed Of Wood-Derived Nanofibrillated Cellulose And Graphene Building Blocks, Qing Li, Ming Dai, Xueren Qian, Tian Liu, Zhenbo Liu, Yu Liu, Ming Chen, Wang He, Suqing Zeng, Yu Meng, Chenchen Dai, Jing Shen, Yingtao Liu, Wenshuai Chen, Wenbo Liu, Ping Lu Jan 2021

Flexible Nanopaper Composed Of Wood-Derived Nanofibrillated Cellulose And Graphene Building Blocks, Qing Li, Ming Dai, Xueren Qian, Tian Liu, Zhenbo Liu, Yu Liu, Ming Chen, Wang He, Suqing Zeng, Yu Meng, Chenchen Dai, Jing Shen, Yingtao Liu, Wenshuai Chen, Wenbo Liu, Ping Lu

College of Science & Mathematics Departmental Research

Nanopaper has attracted considerable interest in the fields of films and paper research. However, the challenge of integrating the many advantages of nanopaper still remains. Herein, we developed a facile strategy to fabricate multifunctional nanocomposite paper (NGCP) composed of wood-derived nanofibrillated cellulose (NFC) and graphene as building blocks. NFC suspension was consisted of long and entangled NFCs (10–30 nm in width) and their aggregates. Before NGCP formation, NFC was chemically modified with a silane coupling agent to ensure that it could interact strongly with graphene in NGCP. The resulting NGCP samples were flexible and could be bent repeatedly without any …

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Research Trend Of Metal Matrix Composites Reinforced With Silica Extracted By Green Route: A Bibliometric Analysis, Rinku Datkhile, Meena Laad, Babaji Ghule Jan 2021

Research Trend Of Metal Matrix Composites Reinforced With Silica Extracted By Green Route: A Bibliometric Analysis, Rinku Datkhile, Meena Laad, Babaji Ghule

Library Philosophy and Practice (e-journal)

Metal Matrix Composites have acquired an important place in the engineering applications due to their distinctive characteristics such as high specific strength, lower specific gravity, improved material stiffness, better durability, enhanced creep and fatigue strength etc. Worldwide scientists are working on the improvement of mechanical properties of composite materials. The present work attempts to summarise all the research carried out on metal matrix composites reinforced with silica extracted by green route and provides up-to-date research material for researchers who are interested in the field of composites with metal matrices. Scopus databases and software such as Gephi Vos Viewer and Table2Net …

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Gas Measurement Device, Megan C. Frost, Weilue He Jan 2021

Gas Measurement Device, Megan C. Frost, Weilue He

Michigan Tech Patents

A device including a first chamber, a second chamber, and a membrane permeable to neutral gases but impermeable to water that is positioned between the first chamber and the second chamber. The membrane includes a first layer including PVDF and PDMS, and the PVDF has a plurality of pores at least partially filled with at least some of the PDMS.

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Corrosion Protective Film Formation On Mg Alloys Az 31 By Exposure To Dilute Selenite Solutions, Zhiyuan Feng, Charles C. Xu, Dadi Zhang, Rudolph Buchheit Jan 2021

Corrosion Protective Film Formation On Mg Alloys Az 31 By Exposure To Dilute Selenite Solutions, Zhiyuan Feng, Charles C. Xu, Dadi Zhang, Rudolph Buchheit

Chemical and Materials Engineering Faculty Publications

The study of protective film formation on Mg alloys by exposure to sodium selenite solutions was conducted. Anodic polarization studies, electrochemical impedance spectroscopy studies, morphological analysis, and Energy-dispersive X-ray spectroscopy were performed on AZ31 Mg alloy after coating treatment in different concentrations of sodium selenite. The corrosion resistance was improved by around 5 times compared with control. Improved resistance to localized corrosion was observed in the coatings treated by 5 mM or 10 mM sodium selenite. The protection mechanism was ascribed to the transformation of selenite to insoluble selenium, the formation of insoluble MgSeO3 hydrate, and polymerization of amorphous …

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Upshot Of Heterogeneous Catalysis In A Nanofluid Flow Over A Rotating Disk With Slip Effects And Entropy Optimization Analysis, Muhammad Ramzan, Saima Riasat, Jae Dong Chung, Yu-Ming Chu, M. Sheikholeslami, Seifedine Kadry, Fares Howari Jan 2021

Upshot Of Heterogeneous Catalysis In A Nanofluid Flow Over A Rotating Disk With Slip Effects And Entropy Optimization Analysis, Muhammad Ramzan, Saima Riasat, Jae Dong Chung, Yu-Ming Chu, M. Sheikholeslami, Seifedine Kadry, Fares Howari

All Works

The present study examines homogeneous (HOM)–heterogeneous (HET) reaction in magnetohydrodynamic flow through a porous media on the surface of a rotating disk. Preceding investigations mainly concentrated on the catalysis for the rotating disk; we modeled the impact of HET catalysis in a permeable media over a rotating disk with slip condition at the boundary. The HOM reaction is followed by isothermal cubic autocatalysis, however, the HET reactions occur on the surface governed by first-order kinetics. Additionally, entropy minimization analysis is also conducted for the envisioned mathematical model. The similarity transformations are employed to convert the envisaged model into a non-dimensional …

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