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Articles 6961 - 6990 of 30003

Full-Text Articles in Mechanical Engineering

Design, Operation And Maintenance Of Direct And Indirect Evaporative Cooling Systems In Data Center Thermal Management, Ashwin Siddarth Aug 2021

Design, Operation And Maintenance Of Direct And Indirect Evaporative Cooling Systems In Data Center Thermal Management, Ashwin Siddarth

Mechanical and Aerospace Engineering Dissertations - Archive

Evaporative cooling is an alternative data center cooling solution that presents significant energy cost savings in acquisition and operation when compared to conventional air conditioning and mechanical refrigeration systems. This research focuses on developing a deeper understanding in implementing, operating and maintaining evaporative cooling systems integrated with air-side economization to realize the energy savings potential in data center cooling. The goal of the research is to develop a comprehensive guide to assess and contrast different approaches of evaporative cooling being used in data center cooling and provide guidance in improving water and energy efficiency. An air handling unit (AHU) serves …


Design Of Streamline-Traced Inlets And Their Integration With Rotating Detonation Engines, Malcolm Lee Branch Aug 2021

Design Of Streamline-Traced Inlets And Their Integration With Rotating Detonation Engines, Malcolm Lee Branch

Mechanical and Aerospace Engineering Theses - Archive

This thesis has two parts: 1) design of the streamline-traced inlets (STIs); and 2) integration of STIs with rotating detonation engines (RDEs). The STI design starts with a two-dimensional, isentropic compression flowfield as the parent flowfield. The method of characteristics was used to generate the flowfield throughout the entire STI. For a given flight altitude 18 km, freestream Mach number M?=3.0, and inlet exit-plane Mach number M?=1.2, a parametric sweep of the initial deflection angle ?1=4.0--11.0 deg and the Mach number at the entrance of the internal compression system M3=1.3--1.7 was performed to determine the STI performance sensitivity as a …


Haptic Interface Optimization For Virtual Anastomosis Surgery Training, Kangji Huang Aug 2021

Haptic Interface Optimization For Virtual Anastomosis Surgery Training, Kangji Huang

Mechanical and Aerospace Engineering Theses - Archive

Virtual anastomosis surgery study allows surgeons to perform or practice suturing in virtual reality using a commercial haptic device. The haptic device can generate force feedback so that the user can feel the real touch sensation of the object in virtual reality. The virtual anastomosis surgery study has two requirements which are that the haptic device must be fixed on the operating table and haptic device location must be suitable for different surgeons. The goal is to use a commercially available haptic device for this purpose, rather than design a new device for each possible surgery that must be performed. …


Design And Cfd Analysis Of Bimetallic Based Passive Dynamic Cold Plate For High Power Direct-To-Chip Liquid Cooling, Apurv Pravin Deshmukh Aug 2021

Design And Cfd Analysis Of Bimetallic Based Passive Dynamic Cold Plate For High Power Direct-To-Chip Liquid Cooling, Apurv Pravin Deshmukh

Mechanical and Aerospace Engineering Theses - Archive

Rising demand for high-performance chips results in the need for advanced and efficient cooling technologies like direct to chip liquid cooling. Cold plates based utilizing direct liquid cooling is one of the most efficient and the most investigated cooling technology since the 1980s. Major data services and cloud providers like IBM, Microsoft, and Google had already started a shift towards liquid-cooled data centers for their high computational servers. At the chip level nowadays, the processors are divided into several cores and each of these cores continuously works at varying computational demands. This creates a non-uniform heat distribution across the processor, …


Simulation Of A Soft Body Non-Grasp Manipulator Using A Spring-Mass-Damper Cloth Model, Cristian Almendariz Aug 2021

Simulation Of A Soft Body Non-Grasp Manipulator Using A Spring-Mass-Damper Cloth Model, Cristian Almendariz

Mechanical and Aerospace Engineering Theses - Archive

Simulation and modeling are well known and important tools in the field of robotics, being used to validate design and in the development of robotic control systems. Traditionally, robotic systems have been primarily rigid body systems and used in well controlled environments where interactions are highly predictable, and exceptions are minimized. With the ever-increasing adoption of robotics in the medical field, typical robotic environments are becoming highly unpredictable and requiring the modeling and simulation of not only rigid body systems but soft systems and interactions between the two. This work addresses model improvement of a “soft and hard” robotic system …


Development Of Virtual Simulation For Evaluation Of Robotic Assistive Environment, Shubham Raosaheb Gunjal Aug 2021

Development Of Virtual Simulation For Evaluation Of Robotic Assistive Environment, Shubham Raosaheb Gunjal

Mechanical and Aerospace Engineering Theses - Archive

Robotics research in virtual simulation has the advantage of reduced testing time, verification of algorithms on different systems before implementation, and cost-saving. Today’s simulation softwares are capable of providing the physics of the simulation such as torque requirements of the joints which aid in the selection of appropriate hardware. In this research, Webots, an open-source physics-based simulation, and visualization software is evaluated and then used to study and evaluate the performance of two robotic systems for a robotic assistive environment for persons with upper limb disabilities. This includes a wheelchair, a table with objects, and two robotic arms attached to …


Investigating A Finite Element Model Updating Methodology For Characterizing Mechanical Properties Of Ncf Composites, Pasworn Chanchai Aug 2021

Investigating A Finite Element Model Updating Methodology For Characterizing Mechanical Properties Of Ncf Composites, Pasworn Chanchai

Mechanical and Aerospace Engineering Theses - Archive

Composite materials have been a key breakthrough in developing aircraft structures. Their superior strength and stiffness-to-density ratio, which are unmatched by no other materials, allow engineers to create high strength and ultra-lightweight aircraft structures. Recently, non-Crimp Fabric (NCF) composites have emerged as attractive alternatives to traditional autoclave pre-impregnated composites allowing for lower production costs, better handling and improved shelf life while maintaining excellent in-plane mechanical properties compared to other types of textile composites. NCF out-of-plane mechanical properties can also be enhanced by stitching a high tensile strength yarn throughout their entire laminate thickness, improving the resistance to delamination. However, stitch-reinforced …


Characterization And Enhancement Of Mechanical Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Rhugdhrivya Rane Aug 2021

Characterization And Enhancement Of Mechanical Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Rhugdhrivya Rane

Mechanical and Aerospace Engineering Dissertations - Archive

Fused filament fabrication is one of the most common and widely used additive manufacturing techniques. Owing to its ease of use, availability and cheap feedstock it provides a significant advantage over other AM techniques. But these advantages are overshadowed by the fact that FFF parts show high anisotropy and reduced mechanical properties as compared to conventional manufacturing techniques. Literature review of previous research works show multiple approaches to enhance the mechanical properties of FFF parts but each of these techniques have limitations to either the geometries that can be printed or involve complex expensive setups. In one such technique a …


Shape Modeling, Attitude Estimation, And Classification Of Artificial Resident Space Objects (Rso) Using Photometric Light Curves, Katiyayni Balachandran Aug 2021

Shape Modeling, Attitude Estimation, And Classification Of Artificial Resident Space Objects (Rso) Using Photometric Light Curves, Katiyayni Balachandran

Mechanical and Aerospace Engineering Dissertations - Archive

Light curve inversion (LCI) has proven valuable in using photometric measurements to optimize various physical parameters of a resident space object (RSO) such as rotational period about its own spin axis, pole orientation and others. Other characteristics such as shape and size are dependent on the surface brightness. To accurately determine size, shape, spin rate, or attitude information of an unresolved resident space object, photometry is required to capture the relatively rapid changes in brightness that these objects can exhibit. LCI has been developed significantly for asteroids, although not fool-proof for artificial RSOs. Satellites and space debris, unlike asteroids, are …


Theoretical And Experimental Analysis And Optimization Of Thermal Conduction In Electrochemical And Latent Heat Energy Storage Systems, Amirhossein Mostafavi Aug 2021

Theoretical And Experimental Analysis And Optimization Of Thermal Conduction In Electrochemical And Latent Heat Energy Storage Systems, Amirhossein Mostafavi

Mechanical and Aerospace Engineering Dissertations - Archive

Phase change materials (PCMs) are used commonly for energy storage purposes. Thermal energy can be stored in a PCM with a variety of configurations such as PCM slabs, cartesian and cylindrical finned systems. Heat transfer in PCM storage systems can be from a heat transfer fluid (HTF) or a heat source at constant temperature to adjacent PCM. The rate of heat transfer is limited by thermal properties. Fin insertion can improve the heat transfer inside the PCM. Chapters 2 and 3 derive and solve the governing energy equations to determine the transient temperature distribution in the PCM due to the …


Rotor Performance Model (Rpm), Chadwick Scott Balfantz Aug 2021

Rotor Performance Model (Rpm), Chadwick Scott Balfantz

Mechanical and Aerospace Engineering Theses - Archive

Rotorcraft performance modeling is of high interest with multiple industry codes in existence, many of which are high-fidelity and are comprehensive in the analyses that are achievable. Along with the high-fidelity and the comprehensive nature of the industry codes comes an equally high level of complexity in the inputs required to extract meaningful results. The ever-increasing fidelity in the existing codes creates a need for an analysis code that is built to be highly flexible, designed from the top down and implemented from the bottom up in a structured format. The Rotor Performance Model (RPM) was developed to provide high-fidelity …


Towards Real-Time Energy Efficiency Analysis Of A Hydraulic System, Montasir Mamun Mithu Aug 2021

Towards Real-Time Energy Efficiency Analysis Of A Hydraulic System, Montasir Mamun Mithu

Masters Theses

The study aims at developing a real-time data analysis system for the energy efficiency study of hydraulic systems. It also aims at implementing automation for hydraulic systems so that energy efficiency can be improved using the real-time approach. This research uses a system-level experimental methodology. A linear push system hydraulic prototype is developed for the study. The prototype contains hydraulic actuator, shock absorber, electronic flow control valve, and electronic sensor. This prototype is used to experiment with different operating conditions to characterize hydraulic system behavior. A real-time data analysis system is developed using LabVIEW and an Open Platform Communication (OPC) …


Surrogate Optimization Model For An Integrated Regenerative Methanol Transcritical Cycle, Yili Zhang Aug 2021

Surrogate Optimization Model For An Integrated Regenerative Methanol Transcritical Cycle, Yili Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In order to reduce the cost ($) per megawatts hour (MWh) of electrical energy generated by a nuclear power cycle with a novel small modular reactor (SMR), a new SMR-based nuclear power cycle with Methanol as working fluid was designed. It was built virtually with the Python & Coolprop software based on all components’ physical properties, and it is therefore called the physics-based model. The physics-based model would require seven user-defined values as input for the seven free design parameters, respectively. The physics-based model outcomes include LCOE (the cost per megawatts hour of electrical energy generated by the …


Nonlinear Model Development And Validation For Ball And Plate Control System, Zachary Richter Aug 2021

Nonlinear Model Development And Validation For Ball And Plate Control System, Zachary Richter

Master's Theses

Ball and plate balancing control systems are commonly studied due to the complex dynamics associated with the instability of the system in open-loop. For simplicity, mathematical models describing the ball and plate dynamics are often linearized and the effects of complex motion are assumed to be negligible. These assumptions are rarely backed with evidence or explanations validating the simplified form of the dynamical equations of motion. This thesis focuses on developing a nonlinear model that more accurately defines the dynamics of the system, in order to quantify the error of linear and nonlinear models when compared to a Simscape physical …


Micro Scalable Graphene Oxide Productions Using Controlled Parameters In Bench Reactor, Carolina S. Andrade, Anna Paula Godoy, Marcos Antônio Gimenes Benega, Ricardo J. E. Andrade, Rafael Cardoso Andrade, Wellington Marcos Silva, Josué Marciano De Oliveira Cremonezzi, Waldemar Augusto De Almeida Macedo, Hélio Ribeiro, Jaime Taha-Tijerina Aug 2021

Micro Scalable Graphene Oxide Productions Using Controlled Parameters In Bench Reactor, Carolina S. Andrade, Anna Paula Godoy, Marcos Antônio Gimenes Benega, Ricardo J. E. Andrade, Rafael Cardoso Andrade, Wellington Marcos Silva, Josué Marciano De Oliveira Cremonezzi, Waldemar Augusto De Almeida Macedo, Hélio Ribeiro, Jaime Taha-Tijerina

Manufacturing & Industrial Engineering Faculty Publications

The detailed study of graphene oxide (GO) synthesis by changing the graphite/oxidizing reagents mass ratios (mG/mROxi), provided GO nanosheets production with good yield, structural quality, and process savings. Three initial samples containing different amounts of graphite (3.0 g, 4.5 g, and 6.0 g) were produced using a bench reactor under strictly controlled conditions to guarantee the process reproducibility. The produced samples were analyzed by Raman spectroscopy, atomic force microscopy (AFM), x-ray diffraction (XDR), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR) and thermogravimetry (TGA) techniques. The results showed that the major GO product comprised of nanosheets containing between 1–5 layers, …


Combustion Of Hydroxylammonium Nitrate Based Monopropellants, Robert Edwin Ferguson Aug 2021

Combustion Of Hydroxylammonium Nitrate Based Monopropellants, Robert Edwin Ferguson

Open Access Theses & Dissertations

"Green" monopropellants based on hydroxylammonium nitrate (HAN) are of interest for replacing highly toxic hydrazine in space propulsion systems and for other applications. Further, gelling such propellants may offer additional advantages such as the long-term stability of compositions with added energetic and catalytic particles in suspension. However, the combustion mechanisms of HAN-based monopropellants and the effect of gelling on their combustion characteristics are poorly understood. In the present work, combustion of an aqueous HAN/methanol solution (70.1 wt% HAN and 14.9 wt% methanol) was studied in a strand burner at nitrogen pressures up to 30 MPa. A version gelled with 1 …


Object Classication, Detection And State Estimation Using Yolo V3 Deep Neural Network And Sensor Fusion Of Stereo Camera And Lidar, Kamalkumar Bharatkumar Mehta Aug 2021

Object Classication, Detection And State Estimation Using Yolo V3 Deep Neural Network And Sensor Fusion Of Stereo Camera And Lidar, Kamalkumar Bharatkumar Mehta

Mechanical and Aerospace Engineering Theses - Archive

Real-time object classification, localization, and detection with region-based convolution neural network (R-CNN) require high computational power, or it consumes a tremendous amount of time with the use of the available onboard computer system. Therefore, either of those ways is not practical in real-time object detection. In contrast, the YOLO-v3 network, which stands for you only look once, that uses the YOLO algorithm seems to be practical in live object classification, localization, and detection, since the YOLO algorithm seems to work faster than the sliding window algorithm used by R-CNN. Sensor fusion in this context requires estimation and association of information …


Design, Development, And Testing Of Research Payloads On Various Suborbital Flight-Test Platforms, Vijay Vishal Duraisamy Aug 2021

Design, Development, And Testing Of Research Payloads On Various Suborbital Flight-Test Platforms, Vijay Vishal Duraisamy

Doctoral Dissertations and Master's Theses

With recent advances in the commercial space industry, suborbital payload launches have become more common and accessible to researchers actively seeking solutions for problems involving prolonged space travel and future missions to Moon and Mars. Suborbital payload missions compared to orbital launches are less expensive and offer faster turnaround times; however, the novelty of this domain provides unique challenges. This multidisciplinary research effort aims to tackle some of these challenges by detailing the design, development, and testing techniques followed in the successful launch and recovery of payload experiments in currently active and upcoming suborbital launch vehicles. The research methodology involves …


Investigation Of Different Hatch Strategies On High Entropy Alloy Fabrication By Selective Laser Melting, Joni Chandra Dhar Aug 2021

Investigation Of Different Hatch Strategies On High Entropy Alloy Fabrication By Selective Laser Melting, Joni Chandra Dhar

Theses and Dissertations

This study investigated the synthesis of CuCrFeNiTiAl high entropy alloy (HEA) from pure elements using selective laser melting (SLM). The objectives are to validate the feasibility of the HEA fabrication from elemental powder materials, and to examine the effect of various hatch strategies and energy densities on the microstructures and other materials properties. 3D samples of CuCrFeNiTiAl alloy were fabricated under different energy densities and with different scan vector lengths. The as-built samples were characterized by X-ray diffraction (XRD), and the microstructures were observed using scanning electron microscopy (SEM). The XRD results showed that face centered cubic, and body centered …


Rapid Annealing Of Perovskite Solar Cell Thin Film Materials Through Intense Pulse Light., Amir Hossein Ghahremani Aug 2021

Rapid Annealing Of Perovskite Solar Cell Thin Film Materials Through Intense Pulse Light., Amir Hossein Ghahremani

Electronic Theses and Dissertations

Perovskite solar cells (PSCs) have garnered a great attention due to their rapid efficiency improvement using cheap and solution processable materials that can be adapted for scalable high-speed automated manufacturing. Thin film perovskite photovoltaics (PVs) are typically fabricated in an inert environment, such as nitrogen glovebox, through a set of deposition and annealing steps, each playing a significant role on the power conversion efficiency (PCE), reproducibility, and stability of devices. However, atmospheric processing of PSCs would achieve lucrative commercialization. Therefore, it is necessary to utilize materials and methods that enable successful fabrication of efficient PSCs in the ambient environment. The …


Development Of A Laser Solder Process For Use With Material Extrusion Additive Manufacturing And Rapid Electronics Prototyping In Embedded Sensing Applications, Emerson Roland Armendariz Aug 2021

Development Of A Laser Solder Process For Use With Material Extrusion Additive Manufacturing And Rapid Electronics Prototyping In Embedded Sensing Applications, Emerson Roland Armendariz

Open Access Theses & Dissertations

Industrial and rapid prototyping (RP) trends toward miniaturization of electronic devices containing temperature sensitive electronics and surrounding materials are calling for highly controllable, selective laser soldering technologies. Laser soldering is a non-contact technique that eliminates the risk of marring or damaging sensitive components by precisely focusing a laser beam on a solder filler alloy, leading to a fast and non-destructive electrical joint. Using the benefits of accurate and controlled heat delivery via inexpensive low power laser diodes (LPDL's) in conjunction with ever-increasing additive manufacturing capability in producing complex internal features and geometries, development and testing of a laser application system …


Vapor-Selective Active Membrane Energy Exchanger For High Efficiency Outdoor Air Treatment, Andrew J. Fix, James E. Braun, David M. Warsinger Aug 2021

Vapor-Selective Active Membrane Energy Exchanger For High Efficiency Outdoor Air Treatment, Andrew J. Fix, James E. Braun, David M. Warsinger

School of Mechanical Engineering Faculty Publications

As much as 40% of the total load on air conditioning systems can be attributed to condensation dehumidification. However, new water vapor-selective membranes present a unique opportunity to greatly reduce the power requirements for moisture removal by avoiding phase change and have thus been ranked as a top alternative to traditional HVAC systems. To date, however, all such systems have relied on the assumption of constant temperature, even terming the technology “isothermal dehumidification.” This work proposes a membrane-based air cooling and dehumidification approach, referred to as the Active Membrane Energy Exchanger (AMX), which is the first to provide simultaneous, yet …


Electrical Characterization Of Phytoplankton Suspensions Using Impedance Spectroscopy., Margaret R Jett Aug 2021

Electrical Characterization Of Phytoplankton Suspensions Using Impedance Spectroscopy., Margaret R Jett

Electronic Theses and Dissertations

Phytoplankton are closely monitored because of their important environmental role, and the impacts they have on their local ecosystems. Some phytoplankton respond to stress by producing lipids, which can be harvested for biofuels and other chemicals. Microfluidic devices have been important in improving the portability and throughput of phytoplankton characterization methods, increasing their potential for in situ use. This study utilized a small sample of phytoplankton suspended in a stagnant medium and measured the impedance response using a lab-on-chip and impedance analyzer. The individual cell characteristics were derived from the impedance response of the group. The goal was to characterize …


Force Spun Pvdf And Tpu Nanofiber Based Triboelectric Nanogenerator For Energy Harvesting And Sensor Application, Sk Shamim Hasan Abir Aug 2021

Force Spun Pvdf And Tpu Nanofiber Based Triboelectric Nanogenerator For Energy Harvesting And Sensor Application, Sk Shamim Hasan Abir

Theses and Dissertations

Flexible and stretchable triboelectric nanogenerator (TENG) is the next generation potential candidate for wearable and portable electronics. In this study, we have demonstrated all nanofiber based TENG for energy harvesting and biomechanical sensing applications. The TENG was prepared by force spun polyvinylidene fluoride (PVDF) and gold (Au) sputtered thermoplastic polyurethane (TPU) nanofiber (NF) layer. The experimental characterization of the PVDF-TPU/Au NF-TENG revealed that surface modification by dispersed gold in TPU fiber membrane resulted the maximum open circuit voltage (254 V) and short circuit current (86 μA) output at 240 bpm (beats per minute) load frequency which was respectively 112% and …


Laser-Induced Forward Transfer (Lift) Based Bioprinting Of The Collagen I With Retina Photoreceptor Cells, Md Shakil Arman Aug 2021

Laser-Induced Forward Transfer (Lift) Based Bioprinting Of The Collagen I With Retina Photoreceptor Cells, Md Shakil Arman

Theses and Dissertations

This thesis focuses on the 3D bioprinting of retina cone cells using the laser-induced forward transfer (LIFT) technique. Bioprinting has a great potential to mimic and regenerate the human organoid system, and the LIFT technique has emerged as an efficient method for high resolution micropatterning and microfabrication of biomaterials and cells due to its capability of creating precise, controlled microdroplets. In this research, the parameters for an effective femtosecond laser-based LIFT process for 3D bioprinting of collagen biomaterial were studied. Different concentrations of collagen I solutions were tested to find out the right concentration that can be transferred through the …


The Processing And Characterization Of Nano Composite Nano Fibers For Various Applications, Md Toukir Hasan Aug 2021

The Processing And Characterization Of Nano Composite Nano Fibers For Various Applications, Md Toukir Hasan

Theses and Dissertations

The study of this thesis focuses on the force spinning of polymer composite nanofibers for antibacterial and energy storage applications. For energy application, Polyacrylonitrile (PAN), Polymethyl methacrylate (PMMA) polymers with active materials (Sn & Ti) and for antibacterial purposes, Polyvinylpyrrolidone (PVP) and Polyethylene-oxide (PEO) polymers along with NPs (Ag and Cu), both were centrifugally spun to get finer nanofibers. The spun produced nanofibers of each types ascertained the percentage of active materials accurately. Antibacterial test on PEO/Ag composite nanofibers exhibited 100% inhibition efficiency against E. coli and B. cereus bacteria while PVP/Cu, PEO/Cu fibrous membranes showed 97.98%, 98.99% respectively. CuNPs …


Fabrication And Characterization Of Polyvinylidene Fluoride Nanofibers For Energy Harvesting Applications, Jui Vitthal Kharade Aug 2021

Fabrication And Characterization Of Polyvinylidene Fluoride Nanofibers For Energy Harvesting Applications, Jui Vitthal Kharade

Theses and Dissertations

Miniaturization of portable devices demand a power source that does not require recharging or replacement. Piezoelectric energy harvesters are devices that harvest mechanical energy from environment and convert it into electrical energy thus being an ideal candidate for replacing batteries in small devices. Objective of this thesis is to fabricate an energy harvester with efficient energy conversion. In this thesis, the effect of fabricating mechanisms, solvents, and composites on polyvinylidene nanofibers are analysed in order to improve the piezoelectric response of the nanofibers. These nanofibers are then used for fabricating an energy harvester. The energy harvester is implemented in a …


Development Of Injection Molding Pressure Monitoring System Using Piezoelectric Sensor, Mostafa Meraj Pasha Aug 2021

Development Of Injection Molding Pressure Monitoring System Using Piezoelectric Sensor, Mostafa Meraj Pasha

Theses and Dissertations

Injection molding is one of the most popular techniques for global plastic production. With this automation technique, the plastic product can be manufactured at a low cost with a complex geometrical shape. A manufacturing process with the high productivity of an injection molding machine depends on molding pressure and temperature inside the mold cavity. In this research, an experimental work is performed to determine a process monitoring system using asynchronous data acquisition, through the incorporation of wired piezo-ceramic sensor to acquire pressure of injection molding system. This piezoelectric sensor is designed in such a way that, a Bluetooth device can …


In-Situ Alloying Of Cucrfenitial High Entropy Alloy Using Spark Plasma Sintering, Yash P. Patil Aug 2021

In-Situ Alloying Of Cucrfenitial High Entropy Alloy Using Spark Plasma Sintering, Yash P. Patil

Theses and Dissertations

Primary objective of this research was to study the correlation between energy parameters (temperature, time and pressure) of spark plasma sintering (SPS) and design/structural properties (uniform distribution of elements, sever lattice distortion, density), indirectly proving consolidation of a stable High-entropy alloy (HEA) that consists of minimum of five elements. Therefore, powders of five principal elements (CuCrFeNiTi) and one minor element (Al) in near equimolar ratios were used for HEA consolidation using SPS but without mechanical alloying. Overall results demonstrated that the HEA was not generated using heterogenous solution of CuCrFeNiTiAl using SPS. This suggests that the mechanical alloying of CuCrFeNiTiAl …


Bioprinting A 3d Tubular Structure With Vascular Smooth Muscle Cells To Observe The Process Compatibility, Taieba Tuba Rahman Aug 2021

Bioprinting A 3d Tubular Structure With Vascular Smooth Muscle Cells To Observe The Process Compatibility, Taieba Tuba Rahman

Theses and Dissertations

Printability is the ability to print a reproducible structure using the bioprinting technique. Constructing the relationships between printability and printing parameters of the extrusion printing process is difficult because of the presence of too many independent and inter-correlated factors. For this reason, it is necessary to identify and limit the number of significantly influential factors. In addition, Scaffold based blood vessel fabrication is a key challenge in 3D Bioprinting. As vascular smooth muscle cell (VSMCs) is a major component of blood vessels, the investigation of the behavior and orientation of VSMCs after printing is required to better understand the 3D …