Open Access. Powered by Scholars. Published by Universities.®

Engineering Science and Materials Commons™

Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 661 - 690 of 2132

Full-Text Articles in Engineering Science and Materials

Superhydrophobic Surface On Aluminum Alloy By Hydrothermal Method And Its Electrochemical Performance, Xiao-Hang Chen, Mo-Jing Chen, Yu-Lin Min, Qun-Jie Xu Feb 2018

Superhydrophobic Surface On Aluminum Alloy By Hydrothermal Method And Its Electrochemical Performance, Xiao-Hang Chen, Mo-Jing Chen, Yu-Lin Min, Qun-Jie Xu

Journal of Electrochemistry

Superhydrophobic film formed on a metal surface is an effective way for corrosion protection. In this paper, the superhydrophobic film was prepared on the surfaces of aluminum alloy by hydrothermally treating with a solution containing CeCl3·7H2O and CO(NH2)2 , and a self-assemble process. The electrochemical measurements and surface morphology results confirmed that the best superhydrophobicity and electrochemical performance could be achieved with the contact angle of 155.5o after six hours of hydrothermal reaction. Furthermore, the inhibition efficiency of 99.6% was obtained in 3.5 wt% NaCl aqueous solution, indicating the excellent corrosion resistance …

Go to article

Intrinsic Kinetic Properties Of Ternary Material For Lithium Ion Batteries Assessed By Single Particle Microelectrode, Yi-Min Wei Feb 2018

Intrinsic Kinetic Properties Of Ternary Material For Lithium Ion Batteries Assessed By Single Particle Microelectrode, Yi-Min Wei

Journal of Electrochemistry

Electrochemical performances such as capacity, rate, cycle and thermal stability of the nickel (Ni), cobalt (Co) and manganese (Mn) ternary cathode material, LiNixCoyMnzO2 (x + y + z = 1), are significantly influenced by the proportion of Ni, Co, and Mn elements. To obtain higher specific capacity, LiNi0.6Co0.2Mn 0.2O2 (NCM622) and LiNi0.8Co0.1Mn0.1O2 (NCM811) with high amounts of Ni element were employed for the lithium ion batteries. By now, many studies have been focusing on the thermal and cycling stabilities of …

Go to article

Preparation And Electrocatalytic Activity Of Nitrogen-Doping Tungsten Carbide Catalyst, Pian-Pian Yang, Li-Zhen Huang, Ying-Ying Li, Mei-Qin Shi, Chun-An Ma Feb 2018

Preparation And Electrocatalytic Activity Of Nitrogen-Doping Tungsten Carbide Catalyst, Pian-Pian Yang, Li-Zhen Huang, Ying-Ying Li, Mei-Qin Shi, Chun-An Ma

Journal of Electrochemistry

Tungsten carbide (WC) is a promising electrocatalyst, however, its electrocatalytic activity is far inferior to Pt and Pt-group metal. In this work, nitrogen-doping tungsten carbide (WN|WC) catalysts with a nanoplate morphology were prepared via the tungsten nitride (WN) as the precursor and sodium tungstate as the tungsten source. The SEM and TEM results indicated that carbon atoms entered into the WN lattice to form the hexagonal close packed WC phase. In this way, an atomic scale heterostructure involving the closely linked interfaces between WN and WC was created . The XRD data confirmed that the cubic crystal structure of WN …

Go to article

Deposition Mechanism And Coating Characterization For The Trivalent Chromium Electrodeposition In Sulphate Electrolyte, Hui Yan, Shuai-Shuai Huang, Fang-Zu Yang, Zhong-Qun Tian, Shao-Min Zhou Feb 2018

Deposition Mechanism And Coating Characterization For The Trivalent Chromium Electrodeposition In Sulphate Electrolyte, Hui Yan, Shuai-Shuai Huang, Fang-Zu Yang, Zhong-Qun Tian, Shao-Min Zhou

Journal of Electrochemistry

Linear sweep voltammetry (LSV) and cyclic voltammetry (CV) were used to study the electrodeposition mechanism of trivalent chromium on a copper electrode in the novel sulphate electrolyte for thick trivalent chromium plating. The thickness, morphology, composition, microhardness, and structure, as well as the corrosion resistance in 3.5wt% NaCl solution of the trivalent chromium coatings were investigated by X-ray fluorescence gage, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), microhardness tester, X-ray diffraction (XRD) and Tafel curve measurements. The results showed that the electrodeposition of trivalent chromium involved two consecutive one electron reduction steps. The first step, Cr3+ + e …

Go to article

Applications Of Electrospinning In Lithium-Air Batteries, Yue Fu, Jin Wang, Hai-Yang Yu, Jing-Hua Tian, Rui-Zhi Yang Feb 2018

Applications Of Electrospinning In Lithium-Air Batteries, Yue Fu, Jin Wang, Hai-Yang Yu, Jing-Hua Tian, Rui-Zhi Yang

Journal of Electrochemistry

Lithium-air batteries have received increasing attention as the “ultimate batteries” due to their extremely high theoretical capacity and environment friendly. However, there are still many obstacles hindering the wide applications of the lithium-air batteries owing to the limitations of large charge-discharge over-potentials, poor Columbic efficiency and cycling performance. Exploring of high-efficiency, low-cost and eco-friendly catalysts is one of the vital issues for lithium-air batteries. Meanwhile, electrospinning techniques have been under substantial developments due to its simple fabrication process, high efficiency and production. This paper reviews the recent progresses in fabrications of various novel catalysts for lithium-air batteries with electrospinning techniques, …

Go to article

Numerical Simulation Of Energy Localization In Dynamic Materials, Arkadi Berezovski, Mihhail Berezovski Feb 2018

Numerical Simulation Of Energy Localization In Dynamic Materials, Arkadi Berezovski, Mihhail Berezovski

Publications

Dynamic materials are artificially constructed in such a way that they may vary their characteristic properties in space or in time, or both, by an appropriate arrangement or control. These controlled changes in time can be provided by the application of an external (non-mechanical) field, or through a phase transition. In principle, all materials change their properties with time, but very slowly and smoothly. Changes in properties of dynamic materials should be realized in a short or quasi-nil time lapse and over a sufficiently large material region. Wave propagation is a characteristic feature for dynamic materials because it is also …

Go to article

An Electrochemical Investigation In The Anticorrosive Properties Of Silver Nanoparticles For The Acidic Corrosion Of Aluminium, H. A. Fetouh, B. A. Abd-El-Nabey, Y. M. Goher, M. S. Karam Feb 2018

An Electrochemical Investigation In The Anticorrosive Properties Of Silver Nanoparticles For The Acidic Corrosion Of Aluminium, H. A. Fetouh, B. A. Abd-El-Nabey, Y. M. Goher, M. S. Karam

Journal of Electrochemistry

The mass loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were used for the determinations of the corrosion rates for aluminium in 1.0 mol·L-1 hydrochloric acid (HCl) solutions both in the absence and presence of silver nanoparticles (SNPs) at 30 ℃. The protection efficiency was evaluated to be 96.4% for 0.014 g·L-1 of the SNPs. It has been found that the capacity of the electrical double layer at the aluminium/solution interface was decreased with increasing the concentration of the SNPs, indicating that the SNPs were adsorbed at the aluminium surface. The Langmuir adsorption isotherm and the kinetic-thermodynamic …

Go to article

Screening Algorithm Based On The Color Halftone Fluorescent Printing And Its Application In Packaging Design, Hu Yaojian, Liu Juan, Wang Ruojing, Zhong Yunfei Feb 2018

Screening Algorithm Based On The Color Halftone Fluorescent Printing And Its Application In Packaging Design, Hu Yaojian, Liu Juan, Wang Ruojing, Zhong Yunfei

Journal of Applied Packaging Research

Abstract：This paper analyzed the characteristics of colorless fluorescent ink and the existing color separation theory, so that colored additive method should be used in printing color pattern with colorless fluorescent ink as well as three-color screening separation type (red, green and blue). Considering the exhibition of the tone, this paper selected dot parallel screening method. At the same time, through comparing the properties of different dots, this paper adopted a special method of AM screening, using regular triangle as the basic dot model to a threshold matrix of AM screening. Finally, designing a screening algorithm which best suit the …

Go to article

Automating The Crowd-Mapping Workflow With Deep Learning, Lasith Niroshan Jan 2018

Automating The Crowd-Mapping Workflow With Deep Learning, Lasith Niroshan

Theses

Maintaining updated maps in an ever-changing built environment is important for supporting modern society in many ways. The usage of online crowdsourced maps in particular has gained importance in a wide range of recent location-based applications (route planning/navigation, urban planning, real estate, tourism, etc). However, both traditional map production methods and updating today’s online maps suffer from early obsolescence due to their largely manual map production/update workflows. Significant research efforts have focused on refining techniques to identify changes in raster satellite images, aiming to improve and streamline map production processes. Concurrently, the surge in Internet usage has led to a …

Go to article

Investigation Of Toppling Ball Flight In American Football With A Mechanical Field-Goal Kicker, Chase M Pfeifer, Timothy J. Gay, Jeff A. Hawks, Shane Farritor, Judith M. Burnfield Jan 2018

Investigation Of Toppling Ball Flight In American Football With A Mechanical Field-Goal Kicker, Chase M Pfeifer, Timothy J. Gay, Jeff A. Hawks, Shane Farritor, Judith M. Burnfield

Department of Mechanical and Materials Engineering: Faculty Publications

A mechanical field-goal kicking machine was used to investigate toppling ball flight in American football place-kicking, eliminating a number of uncontrollable impact variables present with a human kicker. Ball flight trajectories were recorded using a triangulation-based projectile tracking system to account for the football’s 3-dimensional position during flight as well as initial launch conditions. The football flights were described using kinematic equations relating to projectile motion including stagnant air drag and were compared to measured trajectories as well as projectile motion equations that exclude stagnant air drag. Measured football flight range deviations from the non-drag equations of projectile motion corresponded …

Go to article

Solvent And Concentration Effects Governing The Hierarchical Organization Of Asphaltenes: A Small-Angle X-Ray Scattering Study, Hasan Rejoanur Rahman Jan 2018

Solvent And Concentration Effects Governing The Hierarchical Organization Of Asphaltenes: A Small-Angle X-Ray Scattering Study, Hasan Rejoanur Rahman

Open Access Theses & Dissertations

Asphaltenes are a group of planar molecules found in crude oil and are prone to aggregation which often causes blockage of pipes along the oil production stream resulting a huge economic downside. In an effort to understand the hierarchical organization of asphaltene in different solvents and concentrations, the solution structure of various asphaltene solutions were studied using small-angle x-ray scattering (SAXS). Solvents were chosen based on miscibility maps. Such maps are generated on the critical value of the solubility parameter difference between asphaltenes or asphaltene components, and a range of solvents. The critical factors that affect asphaltene and asphaltene component …

Go to article

Spectrally-Selective Energy-Harvesting Solar Windows For Public Infrastructure Applications, Mikhail Vasiliev, Kamal Alameh, Mohammad Alam Jan 2018

Spectrally-Selective Energy-Harvesting Solar Windows For Public Infrastructure Applications, Mikhail Vasiliev, Kamal Alameh, Mohammad Alam

Research outputs 2014 to 2021

A study of photovoltaic solar window technologies is reported and it focuses on their structural features, functional materials, system development, and suitability for use in practical field applications including public infrastructures and agricultural installations. Energy generation performance characteristics are summarized and compared to theory-limit predictions. Working examples of pilot-trial solar window-based installations are described. We also report on achieving electric power outputs of about 25 Wp/m2 from clear and transparent large-area glass-based solar windows.

Go to article

Influence Of Substrate Stage Temperature And Rotation Rate On The Magneto-Optical Quality Of Rf-Sputtered Bi2.1dy0.9fe3.9ga1.1o12 Garnet Thin Films, Mohammad E. Alam, Mikhail Vasiliev, Kamal Alameh Jan 2018

Influence Of Substrate Stage Temperature And Rotation Rate On The Magneto-Optical Quality Of Rf-Sputtered Bi2.1dy0.9fe3.9ga1.1o12 Garnet Thin Films, Mohammad E. Alam, Mikhail Vasiliev, Kamal Alameh

Research outputs 2014 to 2021

Highly bismuth-substituted iron garnet thin films are prepared on quartz substrates by using a radio frequency (RF) magnetron sputtering technique. We study the factors (process parameters associated with the RF magnetron sputter deposition technique) affecting the magneto-optical (MO) properties of ferrite garnet films of composition Bi2.1Dy0.9Fe3.9Ga1.1O12. All films show high MO response across the visible range of wavelengths after being annealed. In particular, the effects of substrate stage temperature and rotation rate on the various properties of films are studied. Experimental results reveal that the characteristics of garnet films of this type can be tuned and optimized for use in …

Go to article

Magnetic And Catalytic Properties Of Transition Metal Doped Mos2 Nanocrystals, Luis Martinez Jan 2018

Magnetic And Catalytic Properties Of Transition Metal Doped Mos2 Nanocrystals, Luis Martinez

Open Access Theses & Dissertations

Magnetism and catalytic activity of nanoscale layered two-dimensional (2D) transition metal dichalcogenides (TMDs) have gained an increasing research interest in the recent past. To broaden the current knowledge and understanding on this subject, in this work, together with my collaborators, I study the magnetic and electrocatalytic properties of hydrothermally grown pristine and transition metal doped (10% of Co, Ni, Fe and Mn) 2H-MoS2 nanosheets/nanocrystals (NCs), with the particle size of 25-30 nm. A broad range of experimental measurements such as x-ray diffraction, transmission electron microscopy, x-ray photo absorption spectroscopy, Raman spectroscopy, magnetic, catalytic and electron spin resonance have been employed …

Go to article

Magneto-Optical Properties Of Thin Permalloy Films: A Study Of The Magneto-Optical Generation Of Light Carrying Angular Momentum, Patrick D. Montgomery Jan 2018

Magneto-Optical Properties Of Thin Permalloy Films: A Study Of The Magneto-Optical Generation Of Light Carrying Angular Momentum, Patrick D. Montgomery

Theses and Dissertations--Electrical and Computer Engineering

Magneto-optical materials such as permalloy can be used to create artificial spin- ice (ASI) lattices with antiferromagnetic ordering. Magneto-optical materials used to create diffraction lattices are known to exhibit magnetic scattering at the half- order Bragg peak while in the ground state. The significant drawbacks of studying the magneto-optical generation of OAM using x-rays are cost, time, and access to proper equipment. In this work, it is shown that the possibility of studying OAM and magneto-optical materials in the spectrum of visible light at or around 2 eV is viable. Using spectroscopic ellipsometry it is possible to detect a change …

Go to article

Consuming Digital Debris In The Plasticene, Stephen R. Parks Jan 2018

Consuming Digital Debris In The Plasticene, Stephen R. Parks

Theses and Dissertations

Claims of customization and control by socio-technical industries are altering the role of consumer and producer. These narratives are often misleading attempts to engage consumers with new forms of technology. By addressing capitalist intent, material, and the reproduction limits of 3-D printed objects’, I observe the aspirational promise of becoming a producer of my own belongings through new networks of production. I am interested in gaining a better understanding of the data consumed that perpetuates hyper-consumptive tendencies for new technological apparatuses. My role as a designer focuses on the resolution of not only the surface of the object through 3-D …

Go to article

Magnetron Sputtering Of Nb3Sn For Srf Cavities, Md. N. Sayeed, H. Elsayed-Ali, G. V. Eremeev, M. J. Kelley, U. Pudasaini, C. E. Reece Jan 2018

Magnetron Sputtering Of Nb3Sn For Srf Cavities, Md. N. Sayeed, H. Elsayed-Ali, G. V. Eremeev, M. J. Kelley, U. Pudasaini, C. E. Reece

Electrical & Computer Engineering Faculty Publications

Nb3Sn is a potential candidate for surface material of SRF cavities since it can enable the cavity to operate at higher temperatures with high quality factor and at an increased accelerating gradient. Nb-Sn films were deposited using magnetron sputtering of individual Nb and Sn targets onto Nb and sapphire substrates. The as-deposited films were annealed at 1200 °C for 3 hours. The films were characterized for their structure by X-ray Diffraction (XRD), morphology by Field Emission Scanning Electron Microscopy (FESEM), and composition by Energy Dispersive X-ray Spectroscopy (EDS) and Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS). The …

Go to article

Preparation Of Nis2 Nanosheet And Its Application In Asymmetric Supercapacitor, Yuan-You Wang, Ya-Nan Liu, Dang-Qin Jin Dec 2017

Preparation Of Nis2 Nanosheet And Its Application In Asymmetric Supercapacitor, Yuan-You Wang, Ya-Nan Liu, Dang-Qin Jin

Journal of Electrochemistry

In this work, the NiS2 nanosheets have been synthesized using Ni(OH)2  as a precursor through a sacrificial template method. The microstructure and chemical composition of as-prepared NiS2 were characterized by XRD, EDS, BET, SEM and TEM techniques. The results showed that both Ni(OH)2  and NiS2  were composed of nanoplates. The electrochemical tests revealed that NiS2 exhibited the high specific capacitance of 1067.3 F•g-1 at a current density of 1 A•g-1 and excellent rate performance. Furthermore, in order to evaluate the practical application of NiS2, an asymmetric supercapacitor, NiS2 as …

Go to article

Electroactivities Of Pd/Fe3O4-C Catalysts For Electro-Oxidation Of Methanol, Ethanol And Propanol, Tao Zou, Qing-Feng Yi, Yuan-Yuan Zhang, Xiao-Ping Liu, Guo-Rong Xu, Hui-Dong Nie, Xiu-Lin Zhou Dec 2017

Electroactivities Of Pd/Fe3O4-C Catalysts For Electro-Oxidation Of Methanol, Ethanol And Propanol, Tao Zou, Qing-Feng Yi, Yuan-Yuan Zhang, Xiao-Ping Liu, Guo-Rong Xu, Hui-Dong Nie, Xiu-Lin Zhou

Journal of Electrochemistry

Development of palladium (Pd) catalysts with high electroactivity for alcohol oxidation is significant for alcohol fuel cells. In this work, Pd nanoparticles were formed by sodium borohydride (NaBH4) reduction method and subsequently deposited on the surface of carbon supported ferriferrous oxide (Fe3O4/C) composites to obtain the Pd/Fe3O4-C catalysts with different Fe3O4 loadings. Their transmission electron microscopic (TEM) images show that the Pd nanoparticles were uniformly dispersed on the Fe3O4/C. Electroactivities of the prepared Pd/Fe3O4-C catalysts toward oxidations of C1-C3 …

Go to article

Kinetics And Mechanism Toward Electrochemical Reductions Of Sodium Bromide And Methanol Over Iron Electrodes, Qun Liao, Shu-Feng Zhang, Wen-Hua Leng Dec 2017

Kinetics And Mechanism Toward Electrochemical Reductions Of Sodium Bromide And Methanol Over Iron Electrodes, Qun Liao, Shu-Feng Zhang, Wen-Hua Leng

Journal of Electrochemistry

It is of technological value and scientific interest to the electro-synthesis of ferrocene, conversion of carbon dioxide (CO2) and organic electro-synthesis in non-aqueous solutions by investigating the kinetics and mechanism toward electrochemical reductions of sodium bromide (NaBr) and methanol over iron electrodes. However, few reports in the related researches are available. In this article, the kinetics and mechanism toward electrochemical reductions of NaBr and methanol over iron electrodes were examined in detail by carrying out the polarization curve and electrochemical impedance spectroscopic measurements. The results showed that methanol was the reactant, while Na+ ions were functioned only …

Go to article

Effect Of Peg-Coating On Properties Of Lithium-Sulfur Battery Cathode Material Containing Carbon Fiber Conductive Agent, Jie-Cheng Tan, Yan-Hong Tian, Xue-Jun Zhang, Kai-Le Fan Dec 2017

Effect Of Peg-Coating On Properties Of Lithium-Sulfur Battery Cathode Material Containing Carbon Fiber Conductive Agent, Jie-Cheng Tan, Yan-Hong Tian, Xue-Jun Zhang, Kai-Le Fan

Journal of Electrochemistry

The composite materials contained high modulus carbon fiber (HMCF) were successfully prepared by employing a ball-milling process based on the coating treatment of polyethylene glycol (PEG), and their structures and morphologies were characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) techniques．The influences of PEG content on sulfur cathode capacity, cycle stability and rate performance were systematically studied. It was found that by the pre-coating of PEG, the cathode exhibited the high initial discharge specific capacity of 1312.5 mAh⋅g-1 at a current rate of 0.2C, and the reversible discharge capacity of 650 mAh⋅g …

Go to article

Capacity Fading Analyses Of Lini0.5Co0.2Mn0.3O2And Lini0.5Co0.2Mn0.3O2/Lifepo4 Cathode Materials For Lithium-Ion Battery, Yi Hu, Xiang-Zhu He, Zhong-De Deng, Ling-Yong Kong, Wei-Li Shang Dec 2017

Capacity Fading Analyses Of Lini0.5Co0.2Mn0.3O2And Lini0.5Co0.2Mn0.3O2/Lifepo4 Cathode Materials For Lithium-Ion Battery, Yi Hu, Xiang-Zhu He, Zhong-De Deng, Ling-Yong Kong, Wei-Li Shang

Journal of Electrochemistry

The LiNi 0.5Co 0.2Mn 0.3O2/LiFePO4 (NMC532/LFP) composite cathode material for lithium-ion battery was prepared by wet ball-milling. The capacity fading behaviors of LiNi 0.5Co 0.2Mn 0.3O2 (NMC532) and LiNi 0.5Co 0.2Mn 0.3O2/LiFePO4 (NMC532/LFP) were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), charge/discharge and electrochemical impedance spectroscopy (EIS) tests. The results indicated that the capacity retention values of NMC532/LFP were 97.80% and 86.48%, respectively, after 50 cycles and 60℃ high temperature storage. The NMC532/LFP exhibited better cycle performance and high temperature storage performance. …

Go to article

Cobalt-Based Nitrogen-Doped Carbon Non-Noble Metal Catalysts For Oxygen Reduction Reaction, Meng-Xiu Jiang, Jing Zhang, Yue-Hua Li, Rong Zhang Dec 2017

Cobalt-Based Nitrogen-Doped Carbon Non-Noble Metal Catalysts For Oxygen Reduction Reaction, Meng-Xiu Jiang, Jing Zhang, Yue-Hua Li, Rong Zhang

Journal of Electrochemistry

Transition metal-nitrogen co-doped carbon catalysts have attracted significant attention because of their reasonable activity and remarkable selectivity toward oxygen reduction reaction (ORR) as cathodic reaction in fuel cells. However, the role of transition metal in the active sites of the catalysts still is uncertain. In this work, the Cox-Ny/C-T catalysts were prepared with BP2000 as a carbon source, urea (Ur) as a nitrogen source and Co(OAc)2•4H2O as a metal precursor by a simple chemical method. Meanwhile, in order to optimize the ORR activity, the catalysts were synthesized with different amounts of Co …

Go to article

Core-Shell Pd@Pt Ultrathin Nanowires As Durable Oxygen Reduction Electrocatalysts, Xin Wang, Yun-Jie Xiong, Liang-Liang Zou, Qing-Hong Huang, Zhi-Qing Zou, Hui Yang Dec 2017

Core-Shell Pd@Pt Ultrathin Nanowires As Durable Oxygen Reduction Electrocatalysts, Xin Wang, Yun-Jie Xiong, Liang-Liang Zou, Qing-Hong Huang, Zhi-Qing Zou, Hui Yang

Journal of Electrochemistry

This paper describes a simple CO-assisted reduction approach for the controllable synthesis of ultrathin Pd nanowires along the one-dimensional (1D) direction. Ultrathin Pt films from one to several atomic layers were successfully decorated onto ultrathin Pd nanowires by utilizing Cu UPD deposition, and followed by in-situ redox replacement reaction of UPD Cu by Pt. The core–shell structure and composition of the Pd@Pt ultrathin nanowires have been verified using transmission electron microscopy and energy dispersive X-ray spectrometry. The core–shell Pd@Pt ultrathin nanowires exhibited comparative electrocatalytic activity and improved durability for the oxygen reduction reaction in comparison with commercial Pt black. The …

Go to article

Effect Of Allyl Thiourea On Nickel Electrodeposition From Solution Containing Ammonia And Chloride, Ya-Ning He, Liang Yuan, Zhi-Ying Ding, Shi-Jun Liu Dec 2017

Effect Of Allyl Thiourea On Nickel Electrodeposition From Solution Containing Ammonia And Chloride, Ya-Ning He, Liang Yuan, Zhi-Ying Ding, Shi-Jun Liu

Journal of Electrochemistry

The effects of allylthiourea (ATU) concentration on the cathodic polarization behaviour, nucleation and surface morphology of nickel electrodeposited on the glassy carbon electrode from ammonia-ammonium chloride-water (NH3-NH4Cl-H2O) solutions were investigated by cyclic voltammogry, cathodic polarization and current transient methods. The results revealed that the addition of ATU inhibited nickel deposition, which was enhanced with an increase in ATU concentration from 5 to 50 mg•L-1. The initial deposition kinetics corresponded to a model including instantaneous nucleation and diffusion controlled growth. In the presence of ATU, the initial nucleation of nickel electrocrystallisation remained unchanged. …

Go to article

Effects Of Jet Milling And Classifying Process On The Performance Of Lifepo4/C In Full Batteries, Xing-Liang Liu, Mao-Ping Yang, Wei-Wei Wang, Yong Cao Dec 2017

Effects Of Jet Milling And Classifying Process On The Performance Of Lifepo4/C In Full Batteries, Xing-Liang Liu, Mao-Ping Yang, Wei-Wei Wang, Yong Cao

Journal of Electrochemistry

The carbon coated lithium iron phosphate (LiFePO4/C) composite cathode material was prepared by using iron phosphate process. The effects of jet milling and classifying process on the electrochemical performance of LiFePO4/C cathode material in full batteries were investigted. Scanning electron microscopic analyses suggested that the globose secondary particles were crustily crushed during the jet milling and classifying process, which would further result in lower tap density and carbon content. The LiFeP4/C composite cathode materials with different physical characteristics were further tested in full batteries to evaluate the electrochemical properties. The results showed no obvious …

Go to article

Engineering The Electrochemical Capacitive Properties Of Activated Carbon By Correct Selection Of Ionic-Liquid Electrolytes, Qiu-Hong Zhang, Bao-Shou Shen, Song-Lin Zuo, Xin-Yu Wei Dec 2017

Engineering The Electrochemical Capacitive Properties Of Activated Carbon By Correct Selection Of Ionic-Liquid Electrolytes, Qiu-Hong Zhang, Bao-Shou Shen, Song-Lin Zuo, Xin-Yu Wei

Journal of Electrochemistry

In order to improve the electrochemical capacitive properties and to apply coconut shell activated carbon (AC) serving as electrode materials in ionic liquid (IL)-based supercapacitor (SC), the coconut shell AC material was re-activated using a steam as an activating agent in this work, forming a secondary AC (W-AC). The results showed that the specific capacitance of the W-AC electrode was much larger than that of the raw activated carbon electrode (R-AC) in 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM]BF4). The electrochemical techniques including cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) measurement, and electrochemical impedance spectroscopy (EIS) were used to systematically study the capacitive …

Go to article

Applications Of N-Methyl-N-Butyl-Pyrrolidinium Bromide And N-Methyl-N-Ethyl-Pyrrolidinium Bromide In Zn-Br Flow Batteries, Qi Zhang, Miao-Miao Zhang, Lin Meng Dec 2017

Applications Of N-Methyl-N-Butyl-Pyrrolidinium Bromide And N-Methyl-N-Ethyl-Pyrrolidinium Bromide In Zn-Br Flow Batteries, Qi Zhang, Miao-Miao Zhang, Lin Meng

Journal of Electrochemistry

It is extremely important for battery performance and safety in Zn-Br flow battery to use quaternary ammonium salts as complex agents for bromine. In this work, the effects of electrolyte compositions and concentrations on the electrode reactions and battery performances were studied in the absence and presences of N-methyl-N-ethyl-pyrrolidinium bromide (MEP) or N-methyl-N-butyl-pyrrolidinium bromide (MBP). The conductivities in the electrolytes containing different constitutions and concentrations were measured by EIS method. The charge-discharge performance for the battery and the complex ability for bromine in different electrolytes were also investigated. The results showed that the electrolyte containing MBP was better than that …

Go to article

Effect Of Fe2+/Fe3+Interconvertion On Reduction Behavior Of Fe3+ In Acidic Electrolytes, Jian-Xin Qin, Feng Lin, Wen-Ping Liu, Chao Chen, Meng-De Ren Dec 2017

Effect Of Fe2+/Fe3+Interconvertion On Reduction Behavior Of Fe3+ In Acidic Electrolytes, Jian-Xin Qin, Feng Lin, Wen-Ping Liu, Chao Chen, Meng-De Ren

Journal of Electrochemistry

The influences of ferrous/ferric (Fe2+/Fe3+) interconvertion on electrochemical reduction and electrode reaction of Fe3+ were investigated by using linear sweep voltammetry, potentiostatic method and cyclic voltammetry (CV) in acidic electrolytes containing chloride ion (Cl-) and sulfate ion (SO42-). It was shown that the reduction process of Fe3+/Fe2+ would take place in two independent stages: (1) the reduction of Fe3+ to Fe2+ at E=0.35V and (2) the co-precipitation of Fe2+ by forming Fe(OH)2 (E≤-0.3 V) instead of Fe. The major effect of Fe2+ …

Go to article

Effect Of Calcium On Atmospheric Corrosion Resistance Of Bridge Steel, Dong-Liang Li, Gui-Qin Fu, Miao-Yong Zhu Dec 2017

Effect Of Calcium On Atmospheric Corrosion Resistance Of Bridge Steel, Dong-Liang Li, Gui-Qin Fu, Miao-Yong Zhu

Journal of Electrochemistry

The corrosion behavior of bridge steel in simulated hot and humid industrial-marine atmosphere was investigated by mass loss analysis, XRD, SEM, electrochemical methods and a wet/dry alternate immersion corrosion test using 0.1 mol•L-1 NaCl+0.01 mol•L-1 NaHSO3 solutions. The corrosion depth (W) of experimental steels before and after calcium treatment versus time (t) curves showed a good agreement with the power function of W=Atn. The corrosion products were mainly composed of amorphous phase and a small amount of crystals including α-FeOOH, β-FeOOH, γ-FeOOH and Fe3O4. Trace calcium could promote the formation of …

Go to article

First Prev Next Last