Contact Angle Measurement Using A Hele-Shaw Cell: A
Proof-Of-Concept Study,
2021
University of Nebraska-Lincoln
Contact Angle Measurement Using A Hele-Shaw Cell: A Proof-Of-Concept Study, Haipeng Zhang, Jacob Gottberg, Sangjin Ryu
Department of Mechanical and Materials Engineering: Faculty Publications
Contact angle is an important property to quantify the wettability of a solid surface with a liquid, which characterizes interactions of the solid-liquid pair. Generally, to measure contact angle, special instruments such as a goniometer are necessary, but they are not readily available in certain research settings. In this study, an alternative method to measure contact angle based on a Hele-Shaw cell, microscopy imaging, and image processing is suggested. In this method, a liquid drop is injected into a transparent Hele-Shaw cell, the meniscus of the drop is captured in the top or bottom view using a brightfield microscope, and …
Yо‘L Harakatini Tashkil Etish Sohasidagi Mavjud Muammolar, Ularning Oqibatlari, Bartaraf Etishga Doir Vazifalar Va Takliflar,
2021
Tashkent State transport University (Tashkent, Uzbekistan)
Yо‘L Harakatini Tashkil Etish Sohasidagi Mavjud Muammolar, Ularning Oqibatlari, Bartaraf Etishga Doir Vazifalar Va Takliflar, I.S. Sodiqov, А.A. Sattorov
The Scientific Journal of Vehicles and Roads
Avtotransport vositalari sonining oshib borayotganligi ularning xavfsizligini ta’minlash va yо‘l harakatini tashkil etishning davr talablariga muvofiq bо‘lgan normativ-huquqiy bazasini ham birdek takomillashtirib borishni taqozo etadi. О‘zbekiston Respublikasida yо‘l harakati xavfsizligi sohasidagi munosabatlar О‘zbekiston Respublikasining “Yо‘l harakati xavfsizligi tо‘g’risida”gi qonuni normalari asosida tartibga solingan
Qattiq Maishiy Chiqindilarni Tekislashda Buldozer Otvalining Samaradorlik Kо‘Rsatkichini Aniqlash,
2021
Tashkent State transport University (Tashkent, Uzbekistan)
Qattiq Maishiy Chiqindilarni Tekislashda Buldozer Otvalining Samaradorlik Kо‘Rsatkichini Aniqlash, N.R. Aslonov, S.M. Mirxoliqov
The Scientific Journal of Vehicles and Roads
Qattiq chiqindilarni utilizasiyalashtirish, kо‘plab rivojlangan va rivojlanayotgan mamlakatlarning shaharlarida ham, qishloq tumanlarida ham juda muhim va keng tarqalgan muammo hisoblanadi. Qattiq maishiy chiqindilarni yig’ish va utilizasiyalashtirish bugungi kunda jahonning kо‘plab mamlakatlarini shahar muhitining asosiy muammolaridan biri. Qattiq maishiy chiqindilarni boshqarish bо‘yicha qarorlar moliyaviy turg’un, texnik amalga oshiriluvchan, ijtimoiy, yuridik maqbul va ekologik toza bо‘lishi kerak. Qattiq chiqindilarni boshqarish masalasi, ham kichik, ham katta shaharlarning xokimiyatlari uchun juda katta muammo hisoblanadi.
Novel Photothermal Materials And Thermally Engineered Membranes For Solar Desalination,
2021
Washington University in St. Louis
Novel Photothermal Materials And Thermally Engineered Membranes For Solar Desalination, Sisi Cao
McKelvey School of Engineering Graduate Student Theses & Dissertations
Although 71% of earth surface is covered with water, more than 97% of it is saltwater, and freshwater is limited to only about 2.5%. The freshwater shortage has been exacerbated due to the environmental pollution, increased agriculture needs, socio-economic development, and population growth. Among various desalination technologies, membrane distillation has gained wide attention due to its ability to treat highly saline water utilizing waste heat from industrial processes. However, the implementation of conventional membrane distillation is hindered in the remote regions and disaster-struck communities where the low-grade thermal energy from industrial plants and electricity are not readily available. To address …
Metal Oxide Nanoparticles Synthesized By Nonthermal Plasma For Electrochemical Applications,
2021
Washington University in St. Louis
Metal Oxide Nanoparticles Synthesized By Nonthermal Plasma For Electrochemical Applications, Qinyi Chen
McKelvey School of Engineering Graduate Student Theses & Dissertations
Metal oxide nanocrystals can be synthesized by colloidal processing and gas-phase processing routes. High-quality nanocrystals produced by colloidal routes typically have surface ligands. Transport of electrons and ions among nanocrystals is hindered by surface ligand, and degrades related electrical performance. Gas-phase processing, for example combustion and thermal plasma, can make free-standing nanocrystals. However, nanocrystals produced by combustion method are heavily agglomerated, which further limits the usage of nanoparticles in electrochemical applications. Nonthermal plasma, as an emerging attractive route, has been initially focused on the synthesis of elemental group IV materials, and extended to include the synthesis of multicomponent materials, such …
Flexible Electronics For Neurological Electronic Skin With Multiple Sensing Modalities,
2021
Washington University in St. Louis
Flexible Electronics For Neurological Electronic Skin With Multiple Sensing Modalities, Haochuan Wan
McKelvey School of Engineering Graduate Student Theses & Dissertations
The evolution of electronic skin (E-skin) technology in the past decade has resulted in a great variety of flexible electronic devices that mimic the physical and chemical sensing properties of skin for applications in advanced robotics, prosthetics, and health monitoring technologies. The further advancement of E-skin technology demands closer imitation of skin receptors' transduction mechanisms, simultaneous detection of multiple information from different sources, and the study of transmission, processing and memory of the signals among the neurons. Motivated by such demands, this thesis focuses on design, fabrication, characterization of novel flexible electronic devices and integration of individual devices to realize …
Nucleation Studies In Barium Silicate Glasses And Soda-Lime Silicate Glass,
2021
Washington University in St. Louis
Nucleation Studies In Barium Silicate Glasses And Soda-Lime Silicate Glass, Xinsheng Xia
McKelvey School of Engineering Graduate Student Theses & Dissertations
Controlling nucleation is key for the manufacture of glasses and glass-ceramics. It has been observed by different researchers in many silicate glasses that at low temperatures the critical work of cluster formation (i.e. the nucleation barrier) slowly rises rather than decreasing with decreasing temperature. However, this experimental observation is in contradiction with nucleation theories. In this dissertation, crystal nucleation was studied in BaO·2SiO2, 5BaO·8SiO2, and Na2O·2CaO·3SiO2 glasses. The main research topics include measurements of the nucleation rate, the structural evolution of the glass, and the low-temperature nucleation behavior. A special focus is given to the low-temperature nucleation anomaly. In total, …
Structure-Property Relationship In High Strength- High Ductility Combination Austenitic Stainless Steels,
2021
University of Texas at El Paso
Structure-Property Relationship In High Strength- High Ductility Combination Austenitic Stainless Steels, Chengyang Hu
Open Access Theses & Dissertations
Austenitic stainless steels are widely used in our daily life, but their mechanical strength is low. In order to improve their yield strength via grain refinement, an investigation was carried out involving phase reversion annealing concept comprising of severe cold roll reduction followed by annealing at different temperatures for short durations. During annealing reversion of deformation-induced martensite to austenite occurred by shear mechanism, leading to fine-grained structure and high strength-high ductility combination.Nanoscale deformation studies suggested that the deformation mechanism of nanograined structure was different from the coarse-grained counterpart. Post-mortem electron microscopy of plastic zone surrounding the indent indicated that the …
Magnesiothermic Combustion Synthesis Of Nanocrystalline Silicon And Oxidation Kinetics Of Magnesium Particles,
2021
University of Texas at El Paso
Magnesiothermic Combustion Synthesis Of Nanocrystalline Silicon And Oxidation Kinetics Of Magnesium Particles, Sergio Cordova
Open Access Theses & Dissertations
Magnesium (Mg) is a well-known reduction agent in metallurgy (more specifically, in metallothermy). Recently, magnesiothermic reduction of oxides has been used in self-propagating high-temperature synThesis (SHS) of advanced materials such as ultrahigh-temperature ceramics (UHTC). The magnesiothermic SHS has also been used for the conversion of silica (SiO2) to silicon-based materials for thermoelectric applications. However, since oxidation of Mg releases a lot of heat, the direct use of it as the reduction agent leads to excessively high temperatures and undesirable sintering of the products. We have proposed to use magnesium silicide (Mg2Si) instead of Mg in the SHS of nanostructured silicon. …
Study Of Halide Gradient Formation Via Solution–Solid Halide Exchange In Crystalline Ch3Nh3Pbbr3 Thin Films,
2021
University of Nebraska-Lincoln
Study Of Halide Gradient Formation Via Solution–Solid Halide Exchange In Crystalline Ch3Nh3Pbbr3 Thin Films, Behnaz Akbari
Department of Chemistry: Dissertations, Theses, and Student Research
In this thesis, attempts have been made to understand halide exchange and mass transport inside the solid lattice of Lead Halide Perovskites (LHPs). We aim for the transformation of MAPbBr3 using ionic solutions including 1-Butyl-3-methylimidazolium iodide (BMIMI), and 1-Butyl-3-methylimidazolium chloride (BMIMCl) as halide ion sources to observe the halide diffusion across the thin film sample and to have LHPs with a gradient of mixed halides (MAPbBr3-x (I/Cl)x, 0 ≤ x ≤ 3). Successfully, MAPbBr3 single-crystalline thin film was fabricated with different configurations. Surface analysis of the LHPs, elemental composition, halide diffusion, roughness, and size of …
Performance Of Calcium Chloride- Ammonia Adsorption Refrigeration System,
2021
University of Dar-es-Salaam
Performance Of Calcium Chloride- Ammonia Adsorption Refrigeration System, Michael John
Tanzania Journal of Engineering and Technology (TJET)
An experimental study on the performance of calcium chloride-ammonia adsorption system is described. A single bed water cooled condenser adsorption refrigerator prototype, which utilises calcium chloride-ammonia pair has been developed and tested in the laboratory. Experiments have been conducted for desorption temperatures of 100 °C with desorption time varying from 1 to 4 hours. An electric tape heater and a timer were used to perform the experiments. The adsorption temperature profile, adsorption rate and prototype performance have been analysed and discussed. The tested heating and desorption temperature of 100 °C and heating and desorption time of 1 to 4 hours …
Assessment Of The Impacts Of Climate Variability On Hydropower Generation: A Case Study Of The New Pangani Falls, Tanzania,
2021
Department of Chemical and Mining Engineering, University of Dar es Salaam
Assessment Of The Impacts Of Climate Variability On Hydropower Generation: A Case Study Of The New Pangani Falls, Tanzania, Dativa Byarufu
Tanzania Journal of Engineering and Technology (TJET)
Climate change poses potential impacts on hydropower generation either positively by increasing or negatively by decreasing river flow. This study assessed the impacts of climate variability on hydropower with a focus on the New Pangani Falls in Tanzania. Rainfall and temperature time series data from 1980-2014 were analyzed in relation to river discharge and associated impacts to hydropower generation. The Man-Kendall test was used to detect trend in both annual and seasonal time series. The results showed a negative trend in annual rainfall with Z= -2.41 at α = 0.05 and the slope Q = -0.964. Seasonal trend analysis showed …
Electrochemical Corrosion Properties Of Ternary Al And Quaternary Zr Added Bell Metal In 0.1m Nacl Solution,
2021
Department of Mechanical Engineering, Bangladesh University of Engineering and Technology, Dhaka, 1000, Bangladesh
Electrochemical Corrosion Properties Of Ternary Al And Quaternary Zr Added Bell Metal In 0.1m Nacl Solution, Sakib Al Razi Khan, Mohammad Ashfaq Hossain, Maglub Al Nur, Mohammad Salim Kaiser
Journal of Mechanical Engineering Science and Technology (JMEST)
The electrochemical corrosion property of ternary Al and quaternary Zr added Bell metal in 0.1M Sodium Chloride solution has been experimentally conducted at room temperature. Electrochemical impedance spectroscopy (EIS) method and Potentiodynamic polarization technique are used to carry out the electrochemical investigation. Microhardness test is also conducted for all three alloys and it reveals that Al addition increases the hardness of bell metal due to the formation of different intermetallic precipitates of Cu and Al. Optical Micrograph as well as Scanning Electron Micrograph have also been studied to characterize their surface condition. It is found that Zr addition refines the …
Evaluating Storage And Effective Moduli Of In Situ Polymerised And Melt Extruded Pa6 Graphite (G) Composites,
2021
Chemical Engineering Department, Kaduna Polytechnic, Nigeria
Evaluating Storage And Effective Moduli Of In Situ Polymerised And Melt Extruded Pa6 Graphite (G) Composites, Muneer Umar, Michael Ikpi Ofem, Auwal Sani Anwar, Muhammad Murtala Usman
Journal of Mechanical Engineering Science and Technology (JMEST)
Four PA6/graphite (G) composites systems were made. Two using in situ polymerisation equivalent in mixing strain and two systems melt extrusion of equivalent processing strain. The effective modulus of the carbons, room temperature storage modulus and storage modulus at 80 ⁰C were evaluated. The composite/unfilled PA6 ratios at E25 and that at E80 for the in situ polymerised system IG 40/10 are 1.37 and 1.63, respectively. For the in situ polymerised system IG 20/20, the same were 1.96 and 2.28, respectively. For the melt-extruded systems, G 100/6 had the best E25 ratio of 1.67 and E80 of 2.03, whereas the …
The Effect Of Thickness And Type Of Material On The Sheared Edge Characteristics Of Keychain Cranioplasty Plate Blanking Product Using Eccentric Press Machine,
2021
Mechanical Engineering, State University of Malang, Indonesia
The Effect Of Thickness And Type Of Material On The Sheared Edge Characteristics Of Keychain Cranioplasty Plate Blanking Product Using Eccentric Press Machine, Didin Zakariya Lubis, Lea Rachmat Indrasepta, Redyarsa Dharma Bintara, Rizky Ramadhan, Agung Budi Darmawan
Journal of Mechanical Engineering Science and Technology (JMEST)
Keychain cranioplasty plate product has the potential to be produced using the blanking process because it is faster, low-cost, and requires low-energy consumption compared to other mechanical operations. This research aimed to find the effect of material thickness and type on the sheared edge characteristics of keychain cranioplasty plate using the blanking process to meet the international health standard. Experimental research conducted using an eccentric press machine with 40 tons capacity. This research’s test material parameters of titanium (Ti-6AL-4V) and stainless steel (SS-316L) were the 0.5 mm, 0.6 mm, and 0.8 mm thickness with a maximum blanking velocity of 3000 …
Effect Of Dcrp And Dcsp Polarity On The Depth Of Penetration Of Smaw On Low Carbon Steel Astm A36 Using E7018 Electrode,
2021
Central for Development of Vocational Serang, Ministry of Manpower, Serang, Indonesia
Effect Of Dcrp And Dcsp Polarity On The Depth Of Penetration Of Smaw On Low Carbon Steel Astm A36 Using E7018 Electrode, Ma'mun Hidayat, Helleni Febnesia, Sulaeman Deni Ramdani
Journal of Mechanical Engineering Science and Technology (JMEST)
The study aims to determine the level of penetration depth using SMAW (Shielded Metal Arc Welding) Process based on the polarity type of DCRP (Direct Current Reverse Polarity) and DCSP (Direct Current Straight Polarity). This research used ASTM A36 low carbon steel plate with thickness of 6 mm and length of 200 mm, Electrode E7018 LB-52-18 ∅ 3.2 mm, and with current parameters of 90 A, 100 A, 110 A, 120 A and 130 A and 70 ° welding arc angle. The method used the experimental research. Data collection techniques applied direct observation techniques and descriptive statistical data analysis techniques. …
Camshaft Failure Simulation With Static Structural Approach,
2021
Mechanical Engineering Department, Universitas Negeri Malang, Indonesia
Camshaft Failure Simulation With Static Structural Approach, Riduwan Prasetya, Andoko Andoko, Suprayitno Suprayitno
Journal of Mechanical Engineering Science and Technology (JMEST)
A failure happens within the camshaft of the minibus when the vehicle is in utilize. The camshaft was a fracture within the bearing between the primary cylinder exhaust valve and the second cylinder suction. This simulation aims to find the causes of camshaft failure utilizing the finite element method with a static structural approach, including simulations of deformation, strain, stress, fatigue life (stress-life and strainlife), and cracks. The method used in this paper is the finite element method with a static structural approach by ANSYS software. The camshaft material is a gray cast iron designed using Solidworks. Pre-processing includes meshing …
The Effect Of Multi-Extrusion Process Of Polylactic Acid On Tensile Strength And Fracture Morphology Of Filament Product,
2021
Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Malang, Indonesia
The Effect Of Multi-Extrusion Process Of Polylactic Acid On Tensile Strength And Fracture Morphology Of Filament Product, Muhamad Syaifuddin, Heru Suryanto, Suprayitno Suprayitno
Journal of Mechanical Engineering Science and Technology (JMEST)
Polylactic acid (PLA) is one of the most used materials in FDM 3D Printing. Large-scale consumption of PLA on an industrial scale could cause environmental and efficiency problems. Thus, PLA waste and industry waste need to be recycled to limit excessive waste. This study aimed to investigate the change in mechanical property, morphology, and structure of mechanically recycled PLA. Recycling was performed 12 times using the extrusion process with an extrusion temperature nozzle of 170°C. The SEM, structural analysis, and amorphous-crystalline analysis used XRD. The results showed a gradual decrease of tensile strength from each recycle with a total of …
Degumming Of Hemp Fibers Using Combined Microwave Energy And Deep Eutectic Solvent,
2021
Louisiana State University and Agricultural and Mechanical College
Degumming Of Hemp Fibers Using Combined Microwave Energy And Deep Eutectic Solvent, Bulbul Ahmed
LSU Master's Theses
Hemp is considered as one of the sustainable agricultural fiber materials. Degumming or surface modification of hemp bast is needed to produce single fibers for ensuing textile and industrial applications. The traditional degumming process necessitates a high amount of alkali, which causes detrimental environmental pollution. This study offers a new method to degum hemp fibers with reduced use of harmful alkali and precious water resources. In this work, hemp bast fibers were degummed by using combined microwave energy and deep eutectic solvent (DES). The properties of hemp fibers manufactured by this method were investigated and compared with the traditional alkali …
Methods , Systems , And Devices
Relating To Surgical End Effectors,
2021
Lincoln , NE
Methods , Systems , And Devices Relating To Surgical End Effectors, Shane M. Farritor, Thomas Frederick, Joe Bartels
Department of Mechanical and Materials Engineering: Faculty Publications
The embodiments disclosed herein relate to various medical device components , including components that can be incorporated into robotic and / or in vivo medical devices, and more specifically including end effectors that can be incorporated into such devices. Certain end effector embodiments include various vessel cautery devices that have rotational movement as well as cautery and cutting functions while maintaining a relatively compact structure. Other end effector embodiments include various end effector devices that have more than one end effector.
