Importance Of Creating A System Of Land And Cadastral Data For Subjects Of Agriculture,
2020
Tashkent Institute of Irrigation and Agricultural Mechanization Engineers
Importance Of Creating A System Of Land And Cadastral Data For Subjects Of Agriculture, К. Rakhmonov
Irrigation and Melioration
The generation of electronic data using the land plot scheme while maintaining the land cadastre provides significant convenience for users. Based on this concept, the author explains the conditions, factors and elements of the formation of the contours of land within the land, which plays an important role in the land cadastral work. In particular, the elements of the contour of the earth, that is, the conditions and composition of the border, the area and the order of formation of numbers, are reflected in a separate figure. It is known that the composition of agricultural land plays an important role …
Me-Em Enewsbrief, March 2020,
2020
Michigan Technological University
Me-Em Enewsbrief, March 2020, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University
Department of Mechanical and Aerospace Engineering eNewsBrief
No abstract provided.
Structural Dynamic And Inherent Damping Characterization Of Additively Manufactured Airfoil Components,
2020
Air Force Institute of Technology
Structural Dynamic And Inherent Damping Characterization Of Additively Manufactured Airfoil Components, Andrew W. Goldin
Theses and Dissertations
The push for low cost and higher performance/efficient turbine engines have introduced a new demand for novel technologies to improve robustness to vibrations resulting in High Cycle Fatigue (HCF). There have been many proposed solutions to this, some passive and some active. With the advent of Additive Manufacturing (AM), new damping techniques can now be incorporated directly into the design and manufacture process to suppress the vibrations that create HCF. In this study, this novel unfused pocket damping technology is applied to a blade structure and the resulting damping effectiveness is quantified. The application of this technology to complex geometries …
Fatigue Behavior Of An Advanced Melt-Infiltrated Sic/Sic Composite With Environmental Barrier Coating At 1200°C In Air And In Steam,
2020
Air Force Institute of Technology
Fatigue Behavior Of An Advanced Melt-Infiltrated Sic/Sic Composite With Environmental Barrier Coating At 1200°C In Air And In Steam, Thaddeus M. Williams
Theses and Dissertations
Advanced aerospace applications such as aircraft turbine engine components, hypersonic flight vehicles, and spacecraft reentry thermal protection systems require structural materials that have superior long-term mechanical properties under high temperature, high pressure, and varying environmental factors, such as moisture. Because of their low density, high strength and fracture toughness at high temperatures SiC fiber-reinforced SiC matrix composites are being evaluated for aircraft engine hot-section components. In these applications the composites will be subjected to various types of mechanical loadings at elevated temperatures in oxidizing environments. Because their constituents are intrinsically oxidation-prone, the most significant problem hindering SiC/SiC composites is oxidation …
Structures And Electrochemical Properties Of Sn-Cl Co-Doped Li2Mno3 As Positive Materials For Lithium Ion Batteries,
2020
1. Powder Metallurgy Research Institute, Central South University, Changsha 410083, China;2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
Structures And Electrochemical Properties Of Sn-Cl Co-Doped Li2Mno3 As Positive Materials For Lithium Ion Batteries, Fei Wang, Huan-Huan Zhai, Du-Dan Wang, Yu-Peng Li, Kang-Hua Chen
Journal of Electrochemistry
Positive material Li2MnO3 shows the highest ratio of lithium to manganese among lithium-rich materials and exhibites the theoretical capacity up to 458 mAh·g-1, making it one of the most promising cathode materials. However, this material has the intrinsic low electrical conductivity and poor cycle stability. In this paper, Li2MnO3, the lithium-rich positive material, was prepared by sol-gel method using acetate as raw material and citric acid as a complexing agent. By using SnC2O4 as a tin source, Sn4+ instead of Mn4+ was introduced to obtain the …
Electrochemical Preparations And Applications Of Nano-Catalysts With High-Index Facets,
2020
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry,College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Electrochemical Preparations And Applications Of Nano-Catalysts With High-Index Facets, Chi Xiao, Na Tian, Zhi-You Zhou, Shi-Gang Sun
Journal of Electrochemistry
The performance of catalysts highly depends on their surface structure and composition. Nanocrystals bounded by high-index facets usually exhibit high catalytic activity due to their high-density low-coordinated step atoms with high reactivity. In this paper, we have reviewed the preparations of noble metals (e.g., Pt, Pd and Rh) nanocatalysts with high-index facets by electrochemical square-wave potential method developed in our group. The square-wave potential method includes a nucleation procedure to generate nuclei, followed by a square-wave potential procedure for a certain period of time for the growth of nuclei into nanocrystals. The formation mechanism of high-index facets is also discussed. …
Recent Progress In The Mechanistic Understanding Of Co2 Reduction On Copper,
2020
Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China;
Recent Progress In The Mechanistic Understanding Of Co2 Reduction On Copper, Matthew M Sartin, Wei Chen, Fan He, Yan-Xia Chen
Journal of Electrochemistry
In this review, we present the major developments in the understanding of the mechanisms of the electrochemical reduction of CO2 from a historical perspective. Most of the work discussed in this review was carried out at copper electrodes, as this is the only material at which hydrocarbons are produced in reasonable quantities. The emphasis focuses on the differentiation of mechanisms for the generation of C1 and C2 products as well as factors and methods for controlling the product selectivity of CO2 reduction. We have highlighted ambiguities, assumptions, and important methodologies, such as differential electrochemical mass spectrometry and electrochemical …
Effect Of Nitrogen Content In Catalyst Precursor On Activity Of Fen/C Catalyst For Oxygen Reduction Reaction,
2020
Scchool of Chemistry and Materials Science, Guizhou Normal University, Guiyang 550000, China;
Effect Of Nitrogen Content In Catalyst Precursor On Activity Of Fen/C Catalyst For Oxygen Reduction Reaction, Zhi Yang, Ya-Yun Shen, E Zhou, Cheng-Ling Wei, Hao-Li Qin, Juan Tian
Journal of Electrochemistry
Non-noble metal catalysts with high activity and low cost have attracted increasing interest as potential catalysts for oxygen reduction reaction (ORR) to replace Pt-based catalysts. In this paper, the effect of nitrogen content in catalyst precursor on ORR activity of FeN/C catalyst was investigated by X-ray diffraction (XRD), Brunauer-Emmet-Teller (BET) surface area and pore size distribution measurements, transmission electron microscope (TEM), thermogravimetric analysis (TGA), and rotating disk electrode (RDE) techniques. The results show that the most active catalyst was obtained by pyrolysis in argon at 1050 °C with a catalyst precursor containing 20wt% 1,10-phenanthroline, 1wt% Fe and Black Pearl 2000. …
Lithium Storage Performance Of High Capacity Material Si@CPzs In Lithium Ion Batteries,
2020
1. Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China;2. University of Chinese Academy of Sciences, Beijing 100080, China;
Lithium Storage Performance Of High Capacity Material Si@CPzs In Lithium Ion Batteries, Qing-Nuan Zhang, Fang-Fang Zhang, Hong-Xia Li, Bing-Jun Yang, Xiao-Cheng Li, Juan Yang
Journal of Electrochemistry
Carbon layers with different thicknesses were introduced into the surfaces of silicon (Si) nanoparticles by sol-gel method using poly (cyclotriphosphazene-co-4, 4'-sulfonyldiphenol) as the carbon source. Technologies of X-ray diffraction, thermo-gravimetric analysis, Brunauer-Emmett-Teller and transmission electron microscopy were employed to analyze the structures and components of the as-prepared Si@CPZS composites. Electrochemical performance of Si@CPZS with different carbon thicknesses was studied. The results showed that Si@CPZS with carbon thickness of 10 nm possessed the best performance. Its capacity remained 940 mAh·g-1 after 290 cycles under 500 mA·g-1. As the addictive, the graphite-based anode contained 30% of …
Research Progresses In Ni-Co-Mn/Al Ternary Concentration Gradient Cathode Materials For Li-Ion Batteries,
2020
1. College of Energy, Xiamen University, Xiamen 361102, Fujian, China;
Research Progresses In Ni-Co-Mn/Al Ternary Concentration Gradient Cathode Materials For Li-Ion Batteries, Chun-Fang Zhang, Wen-Gao Zhao, Shi-Yao Zheng, Yi-Xiao Li, Zheng-Liang Gong, Zhong-Ru Zhang, Yong Yang
Journal of Electrochemistry
Nickel-rich ternary materials with large reversible capacity as well as high operating voltage are considered as the most promising candidate for next generation lithium-ion batteries (LIBs). However, the inferior cycle stability and thermal stability have limited their widely commercial applications. Concentration gradient design of Ni-Co-Mn/Al ternary concentration gradient materials have been extensively studied in the past decade, which can ensure high cycle capacity while maintaining excellent cycle stability. In this paper, the latest research progresses in Ni-Co-Mn/Al ternary concentration gradient materials for LIBs are reviewed. Firstly, we summarize the different synthesis methods of ternary concentration-gradient materials, especially focusing on the …
Challenges In The Activity And Stability Of Pt-Based Catalysts Toward Orr,
2020
1. School of Applied Chemistry and Engineering University of Science and Technology of China,Hefei 230026, Anhui ,China;2. State Key Laboratory of Electroanalytica Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences University of Chinese Academy of Sciences, Changchun 130022, Jilin, China;
Challenges In The Activity And Stability Of Pt-Based Catalysts Toward Orr, Tuo Zhao, Er-Gui Luo, Xian Wang, Jun-Jie Ge, Chang-Peng Liu, Wei Xing
Journal of Electrochemistry
The development of highly efficient oxygen reduction reaction (ORR) catalysts is the key to the commercialization of fuel cells, where the sluggish ORR reaction rate needs to be overcome by adjusting the intermediates adsorption energies on the catalytic surfaces. To-date, platinum (Pt)-based materials are the-state-of-the-art catalysts in terms of both activity and stability in ORR, making them the preferred choice for commercial applications. However, the high cost of Pt-based catalysts limits their widespread use, leading to massive effects paid in reducing Pt loading, improving catalyst activity and stability. This article illustrates the challenges in the ORR reaction and introduces the …
Research Progresses In Polymeric Proton Exchange Membranes For Fuel Cells,
2020
1. Sustainable Energy Laboratory, Faculty of Materials Science and Chemistry, China University of Geosciences Wuhan, Wuhan 430074, China;2. Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology), Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China;
Research Progresses In Polymeric Proton Exchange Membranes For Fuel Cells, Xu-Po Liu, Yun-Feng Zhang, Shao-Feng Deng, De-Li Wang, Han-Song Cheng
Journal of Electrochemistry
Proton exchange membrane (PEM) is one of the key components in PEM fuel cells, which possesses the function of separating the cathode and anode, affording proton transport channels and preventing fuel permeability. The property of PEM significantly influences the performance and service life of fuel cells. Nowadays, the commercially used Nafion membranes have the shortcomings of serious fuel permeability, low proton conductivity at elevated temperature and high price, which limits the rapid development of PEM fuel cells. Therefore, it seems to be urgent to develop novel PEMs with low cost and good comprehensive properties. Polymeric proton exchange membrane is an …
Preparations Of Nickel-Iron Hydroxide/Sulfide And Their Electrocatalytic Performances For Overall Water Splitting,
2020
1. College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China;
Preparations Of Nickel-Iron Hydroxide/Sulfide And Their Electrocatalytic Performances For Overall Water Splitting, Hang-Shuo Lu, Xiao-Bo He, Feng-Xiang Yin, Guo-Ru Li
Journal of Electrochemistry
The Ni-Fe/Ti oxygen evolution electrode was prepared by electrodeposition on a titanium mesh substrate. Then, the as prepared Ni-Fe/Ti electrode was used to derive the Ni-Fe-S/Ti hydrogen evolution electrode through solid phase sulfuration. The effects of the molar ratio of Ni2+ to Fe3+ in the electrolyte and the amount of thiourea on the structures and electrochemical performances of Ni-Fe/Ti and Ni-Fe-S/Ti electrodes were investigated. The results show that the oxygen evolution performance of Ni-Fe/Ti electrode was first increased and then decreased with the increase of nickel ion content in the electrolyte. The Ni9Fe1/Ti electrode exhibited the best oxygen …
Atomic Force Microscopic Characterization Of Solid Electrolyte Interphase In Lithium Ion Batteries,
2020
1. i-Lab, CAS Center for Excellence in Nanoscience, Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences (CAS), Suzhou 215123, China;
Atomic Force Microscopic Characterization Of Solid Electrolyte Interphase In Lithium Ion Batteries, Qing-Yu Dong, Yan-Li Chu, Yan-Bin Shen, Li-Wei Chen
Journal of Electrochemistry
In recent years, the rapid growing in the electric vehicle market has raised higher requirement on the lithium-ion batteries (LIBs) performance towards energy density and safety. However, considering the successful development of LIBs techniques in the past 30 years, there is little room left for improving the LIBs performance on the aspects related to the electrode materials, battery structure design and production processes. It is important to pursue more comprehensive fundamental understanding in the entire system and working principle of LIBs. Solid electrolyte interphase (SEI), existing between the electrode material and the electrolyte, has been proved to be an important …
Preparation And Electrocatalytic Performance Of Nico2O4/Ni Foam For Hydrogen Peroxide Electrooxidation,
2020
College of Material Science and Chemical Engineering, Harbin Engineering University,Harbin 150001, Heilongjiang, China;
Preparation And Electrocatalytic Performance Of Nico2O4/Ni Foam For Hydrogen Peroxide Electrooxidation, Wei-Wei Chen, Fei-Fan Zhang, Jia-Liang Du, Yi Wang, Chun-Lin Zhao, Kai Zhu, Dian-Xue Cao, Gui-Ling Wang
Journal of Electrochemistry
The electrodes of Ni foam supported NiCo2O4 nanowires were prepared by hydrothermal method, followed by a thermal treatment in air, and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that the NiCo2O4 nanowires had a diameter of about 50 nm with a length up to 3 ~ 5 μm. The catalytic performances of the Ni foam supported NiCo2O4 nanowires for H2O2 electrooxidation were studied by cyclic voltammetry and chronoamperometry. The results show that the Ni foam supported NiCo …
Manufacturing And Characterization Of Glass Fiber-Fishnet-Woven Roving And Polyester Composites,
2020
Assistant Professor, Department of EEE, University College of Engineering Nagercoil, Tamilnadu, India.
Manufacturing And Characterization Of Glass Fiber-Fishnet-Woven Roving And Polyester Composites, S. Sahaya Elsi, F. Michael Raj, Mary S. Prince, A. Amala Mithin Minther Singh, R. S. Jayaram
Journal of Marine Science and Technology–Taiwan
Glass fibers are imparted as reinforcement material in polyester matrix and still it act as a preferred material for the marine industry. However, it is non-biodegradable material and involves high risk during processing. In this study, new monofilament fishnets were substituted as an alternative material for glass fiber in the polyester matrix. Mechanical properties of these composite specimens such as tensile strength, flexural strength and impact resistance in accordance with ASTM, were evaluated. SEM images of various composites revealed the relations between the reinforced fishnet/glass fiber and woven roving with polyester matrix. The dynamic mechanical analysis of storage modulus, loss …
Cycle-To-Cycle Flow Variations In A Square Duct With A Symmetrically Oscillating Constriction,
2020
University of Nebraska-Lincoln
Cycle-To-Cycle Flow Variations In A Square Duct With A Symmetrically Oscillating Constriction, Erica Sherman, Lori M. Lambert, Bethany White, Michael H. Krane, Timothy Wei
Department of Mechanical and Materials Engineering: Faculty Publications
Spatially and temporally resolved Digital Particle Image Velocimetry (DPIV) measurements are presented of flow complexities in a nominally two-dimensional, symmetric, duct with an oscillating constriction. The motivation for this research lies in advancing the state-of-the-art in applying integral control volume analysis to modeling unsteady internal flows. The specific target is acoustic modeling of human phonation. The integral mass and momentum equations are directly coupled to the acoustic equations and provide quantitative insight into acoustic source strengths in addition to the dynamics of the fluid-structure interactions in the glottis. In this study, a square cross-section duct was constructed with symmetric, computer …
Electromechanics Modelling Of The Effects Of Myocardial Infarction On Left Ventricular Remodelling,
2020
Universiti Malaya
Electromechanics Modelling Of The Effects Of Myocardial Infarction On Left Ventricular Remodelling, Chin Neng Leong
Student Works (2020-2029)
Myocardial infarction (MI) is one of the diseases with the highest mortality rate. Following MI, myocardium experiences abrupt changes in its loading condition due to the presence of infarct. In response to such changes, myocytes undergo adaptations to maintain homeostasis. However, maladaptation can happen and lead to remodelling, in which the left ventricle (LV) gradually loses its function and eventually turns into heart failure. Nevertheless, the mechanisms underlying LV remodelling are still poorly understood. In this study, a generic LV model was developed, incorporating realistic fibre orientation and excitable contracting myocardium. It was demonstrated that the developed model is capable …
Kinematic Analysis Of Forehand Drop Shot And Long Shot Services In Table Tennis,
2020
Universiti Malaya
Kinematic Analysis Of Forehand Drop Shot And Long Shot Services In Table Tennis, Ibrahim Norzuria
Student Works (2020-2029)
Table tennis is one of the most widely played sports in the world. A frequent hand movement is compulsory to execute stroke than other limbs, especially the projection of racket and ball speeds,which can help to improve players’ performance. Until now, research on table tennis serving is limited. Service was assumed important in table tennis because the effective serve may allow the serving player to have advantage and control over the game. The 3D dynamic analysis is the appropriate method to analyze a sport activity such as table tennis. Therefore, the aim of research was to determine the kinematic involved …
Dual-Axis Solar Tracker,
2020
Central Washington University
Dual-Axis Solar Tracker, Bryan Kennedy
All Undergraduate Projects
Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in …
