Engineering Commons^™

Short Review On Electrochemical Energy Storage, Hong Li, Ying-Chun Lyu

Journal of Electrochemistry

Energy storage is a critical supporting technology in many fields such as energy, information, transportation, and healthcare, aerospace, advanced manufacture, advanced equipment, national security. Electrochemical energy storage technique has been widely applied and is developing continuously. In this article, the energy storage mechanism, technical indicators and technology ready level in electrochemical energy storage are summarized. Mainly based on lithium ion batteries, untraditional electrochemical issues in electrochemical energy storage devices are described from the perspective of fundamental science. These issues deal mainly with thermodynamics, kinetics, size effect, asymmetric system, asymmetric reaction path, surface phenomenon, hybrid ion transportation, and solid state battery. …

Research Progress Of Secondary Sodium-Air Batteries, San-Pei Zhang, Zhao-Yin Wen, Jun Jin, Xiang-Wei Wu, Ying-Ying Hu, Mei-Fen Wu

Journal of Electrochemistry

Rechargeable sodium-air batteries have been the focus in the fields of batteries and energy storage recently, owing to their high specific energy density (1600 Wh·kg^-1), an equilibrium discharge potential of 2.3 V and earth-abundant sodium element However, research on sodium-air cells is still in an infant age and presents many scientific issues. Based on recently reported work and our own experience on sodium-based batteries, this review summarizes the research progress related to the critical scientific is sues of secondary sodium-air batteries and the application prospect of sodium-air battery.

Preparations And Properties Of Polybenzimidazole/Polyvinylbenzyl Crosslinked Composite Membranes For High Temperature Proton Exchange Membrane Fuel Cells, Jin-Kai Hao, Yong-Yi Jiang, Zhen Wang, Xiao-Jin Li, Zhi-Gang Shao, Bao-Lian Yi

Journal of Electrochemistry

In order to increase the chemical stability of polybenzimidazole (PBl) membrane, a highly stable polymer, poly vinyl. benzyl chloride (PVBC), was chosen as the macromolecular crosslinker, and 1H-1,2,4-triazol was adopted to prepare the crosslinked PBI-based membranes. The influence of the PVBC amount on membrane characteristic was investigated in detail. The results indi. cated that the crosslinked structure of the membrane effectively improved the chemical stability, and at the same time, the mem. brane presented good mechanical property and proton conductivity. The fuel cell performance for the membrane was tested with hy. drogen and oxygen single cell without humidification at 150 …

Development Of Proton Conduction Membranes In Application Of Vanadium Flow Battery, Le-Tu Qingge, Wei-Nan Guo, Ping Liu, Bao-Guo Wang

Journal of Electrochemistry

The polymeric hydrophilic/hydrophobic interactions into membrane formation were introduced. A general and straightforward strategy for preparing membranes with nanometer-scale pores was suggested by utilization of hydrophilic/hydrophobic interactions to generate phase separation and removal of polyion aggregates through water immersion. Poly(vinylidene fluoride) (PVDF) and sodium allyl sulfonate (SAS) serve as the membrane material and pore-generator, respectively, resulting in chemically stable and oxidation-resistant membranes with various potential applications. Following the same procedure invented to produce the laboratory-scale membranes, the scale-up process to manufacture large-area membranes was completed. The obtained membrane exhibited the conductivity of 3.5×10^-2 S•cm^-1, thickness of 100 …

Review For Applications Of "Lead Carbon" Batteries In Energy Storage System, Yong-Quan Ma, Ke Ke, Da-Ming Gu

Journal of Electrochemistry

Three types of “lead carbon” batteries are introduced by comparing their advantages and disadvantages. Then their applications in energy storage system (ESS), especially in the field of renewable energy power generation, are discussed. The prospects and potential applications of “lead carbon” batteries in EES for electric power supply system are analyzed by combining the state-of-the-art techniques in this field.

Characterization Of The Separator With Thermal-Shutdown Layer For Use In Lithium Batteries, Li Bai, Yong-Jian Huai, Xin-Ping Ai, Hai Jia

Journal of Electrochemistry

In this paper, the lithium ion battery coated with the thermal-shutdown functional layer has been introduced. The shutdown temperature of the separator could be decreased by using the melting point of thermal-shutdown functional layer. When the internal battery environment reached a critical temperature, the functional layer melted and coated the anode/separator with a non-conductive barrier, halting Li-ion transport and shutting down the cell permanently. The results showed that the functional layer did not affect the resistance, rate performance and cycle life. It was found the functional layer can significantly improve the safety of the battery when misused.

Impact Of Water Content On The Performance Of Lifepo4 Based Lithium-Ion Battery, Jun-Ting Niu, Lin Sun, Shu-Wen Kang, Zhen-Wei Zhao, Zi-Feng Ma

Journal of Electrochemistry

Through different dry conditions and measuring by moisture test instrument, cathode pole pieces with different water contents of 0.3‰ ~ 0.7‰ were obtained to prepare lithium-ion batteries. Cycling performance and high rate performance at 1C ~ 5C discharge rates were tested. Moreover, ASR performances of LiFePO4 base lithium-ion batteries after 200 cycles with different water contents were investigated by EIS. The results showed that the cycle performance and rate performance were closely related to the water content of the electrode. When the water content went up to 0.6‰ the cycle stability and rate performance fell. Meanwhile, the internal resistance and …

Effects Of Microstructures Of Active Material On Performance Of Vrla Battery, Lei Jiang, Shou-Zhong Yi

Journal of Electrochemistry

The structure, morphology and content of the as-prepared and the processed samples were characterized by the means of SEM and XRD. The discharge capacities and cycle life performances of the as-prepared and the processed samples were tested by electrochemical measurements with different rates. The results indicated that the 4BS technology which can affect the plate design, deep cycle capability and cycle life is a basic technology for the VRLA batteries. It was also confirmed that the contents and structures of α-PbO₂ and β-PbO₂ formed with different processing conditions can affect the performance of the VRLA batteries, suggesting that …

Preparation And Performance Of Lithium-Rich Manganese Layered Materialsâ 0.6li[Li1/3Mn2/3]O2·0.4liniXMnYCo1-X-YO2(X < 0.6, Y > 0), Hai-Lan Feng, Ya-Fei Liu, Yan-Bin Chen

Journal of Electrochemistry

Lithium-rich manganese based cathode materials 0.6Li[Li_1/3Mn_2/3]O₂⋅0.4LiNi_xMn_yCo_1-x-yO₂ (x < 0.6, y > 0) were synthesized by carbonate co-precipitation and high temperature solid-state reaction. The structures and morphologies of the as-prepared materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM). The results of high temperature in-situ XRD test show that the lattice parameters change significantly with increasing temperature and Ni content. The cation mixing gets serious and the spinel phase appears in the high Ni content samples when the temperature is up to 800 oC. Under voltages ranging from 2.0 to …

Tackling Salinity In The Colorado River One Ion At A Time | Biological Engineering, Usu College Of Engineering

College of Engineering News

10/27/2015 - It’s one of the most overtaxed waterways on the planet, and its shrinking flow is only part of the problem.

The Colorado River travels 1,500 miles through seven U.S. states before reaching the Gulf of California. Throughout its long journey the river supplies water for approximately 40 million people and is used to irrigate more than five million acres of land in the Western U.S. and Mexico.

Electrical & Computer Engineering News, Georgia Southern University

Electrical & Computer Engineering: News & Publications (2014-2023)

• GS Undergraduate Research: Robotic Arm for Mimicking Human Arm Movements

Smartphone Based 3d Printed Colorimeter For Biomedical Applications, Karthik Raj Konnaiyan

USF Tampa Graduate Theses and Dissertations

Here we present a novel Smartphone-based colorimeter and demonstrate its application to the measurements of glucose and protein concentrations in biological samples. The key innovation of our approach was to combine powerful image processing encoded into a mobile phone application with a low cost 3D printed sample holder that allowed to control lighting conditions and significantly improved sensitivity. Different solutions with protein and glucose concentrations ranging from 0 to 2000 mg/dL were prepared and analyzed using our system. The Smartphone-based colorimeter always correctly classified the corresponding reagent strip pads, what confirms that it can be used as a low cost …

Process Optimization To Enhance Quality And Quantity Of Transiently Expressed Proteins | Biological Engineering, Usu College Of Engineering

College of Engineering News

Transient transfection is a method to introduce foreign DNA into a healthy cell population. Transient transfection can be accomplished by chemical, mechanical, and electrical delivery. Although foreign DNA is not incorporated into the host cell genome, host cell machinery is used to transcribe and translate the gene of interest. This presentation will illustrate the enhancement of transgene production through reagent optimization and feeds and show benefits of transient work, such as, eliminating the need for generation of a stable engineered cell line; allowing the process scaleability; and decreasing the time for generation of comparable amounts of product.

Practitioner Interview, Ron Anderson

All ECSTATIC Materials

Phone interview with Ron Anderson from LCRA by Paul Block and Ali Mirchi. Interview questions asked inquired about (i) practitioner’s professional background, (ii) practitioner’s personal experience with systems analysis techniques and software in their job, (iii) role, benefits, and challenges in using systems analysis concepts in the water resources engineering profession, and (iv) recommendations for improving education of environmental and water resources systems analysis in universities.

Electrode Kinetics Of Vanadium Flow Batteries: Contrasting Responses Of VIi-VIii And VIv-VV To Electrochemical Pretreatment Of Carbon, A. Bourke, M. A. Miller, R. P. Lynch, Xin Gao, James Landon, J. S. Wainright, R. F. Savinell, D. N. Buckley

Center for Applied Energy Research Faculty and Staff Publications

Electrochemical impedance spectroscopy and cyclic voltammetry were used to investigate the electrode kinetics of V^II-V^III and V^IV-V^V in H₂SO₄ on glassy carbon, carbon paper, carbon xerogel, and carbon fibers. It was shown that, for all carbon materials investigated, the kinetics of V^II-V^III is enhanced by anodic, and inhibited by cathodic, treatment of the electrode; in contrast, the kinetics of V^IV-V^V is inhibited by anodic, and enhanced by cathodic, treatment. The potential region for each of these effects varied only slightly with carbon material. Rate constants …

High Temperature Proton Exchange Membranes With Enhanced Proton Conductivities At Low Humidity And High Temperature Based On Polymer Blends And Block Copolymers Of Poly(1,3-Cyclohexadiene) And Poly(Ethylene Glycol), Shawn Deng, Mohammad K. Hassan, Amol Nalawade, Kelly A. Perry, Karren L. More, Kenneth A. Mauritz, Marshall T. Mcdonnell, David J. Keffer, Jimmy W. Mays

Faculty Publications

Hot (at 120 °C) and dry (20% relative humidity) operating conditions benefit fuel cell designs based on proton exchange membranes (PEMs) and hydrogen due to simplified system design and increasing tolerance to fuel impurities. Presented are preparation, partial characterization, and multi-scale modeling of such PEMs based on cross-linked, sulfonated poly(1,3-cyclohexadiene) (xsPCHD) blends and block copolymers with poly(ethylene glycol) (PEG). These low cost materials have proton conductivities 18 times that of current industry standard Nafion at hot, dry operating conditions. Among the membranes studied, the blend xsPCHD-PEG PEM displayed the highest proton conductivity, which exhibits a morphology with higher connectivity of …

Reconstructing The Natural Hydrology Of The San Francisco Bay - Delta Watershed, P. Fox, P.H. Hutton, D.J. Howes, A.J. Draper, L. Sears

BioResource and Agricultural Engineering

We evaluated the impact of landscape changes on the amount of delta outflow reaching San Francisco Bay. The natural landscape was reconstructed and water balances were used to estimate the long-term annual average delta outflow that would have occurred under natural landscape conditions if the climate from 1922 to 2009 were to repeat itself. These outflows are referred to as natural delta outflows and are the first published estimate of natural delta outflow. These natural delta outflows were then compared with current delta outflows for the same climate and existing landscape, including its re-engineered system of reservoirs, canals, aqueducts, and …

Brigham Young University Honors Usu's Todd Moon | College Of Engineering, Usu College Of Engineering

College of Engineering News

Originally posted Oct. 22, 2015 – Brigham Young University’s department of electrical and computer engineering has named its alumn and current USU professor and department head Todd Moon as a 2015-2016 Honored Alumnus.

The university made the announcement the week of Oct. 19. Dr. Todd K. Moon received his double BS in electrical and computer engineering and mathematics in 1988, and a master's degree in electrical engineering also in 1988 from Brigham Young University.

Hierarchical Equivalent Source Algorithm Based On Relaxed Spherical Equivalence Surface, Xin Fu, Li (Lijun) Jun Jiang, Hong Tat Ewe

Electrical and Computer Engineering Faculty Research & Creative Works

A new hierarchical algorithm based on surface equivalence principle is proposed in this work. The equivalent sources residing on relaxed spherical equivalence surfaces are computed by closed-form integral operators rather than numerical approximations. Consequently, a hierarchical algorithm based on oct-tree is straightforward to implement. Numerical examples validate the accuracy and capability of the proposed algorithm.

A Supercell Based Dual Beam Dielectric Grating Antenna For 60 Ghz Application, Zi Long Ma, Chi Hou Chan, Kung Bo Ng, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

A dual-beam dielectric grating antenna based on the supercell (SC) concept is presented in this paper. Theoretical analysis shows that with the perturbations of different unit cells (UC), two space harmonic modes (m = -1 and m = -2) are excited (above the air line) in the dispersion diagram of the supercell in a certain frequency range. This phenomenon leads to the generation of two radiation beams in the far-field region. At the operating frequency where the phase constants β-1 =β in symmetric directions. In addition, a symmetric SC is proposed and carefully designed to achieve equal performance (beam width …

Calculating The Scattered Fields From The Fock Currents Of The 3-D Convex Scatterers By The Incremental Length Diffraction Technique, Yu Mao Wu, Weng Cho Chew, Tie Jun Cui, Ya Qiu Jin, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, we consider the accuracy improvement of the high frequency scattered fields from the 3-D convex scatterers with the aid of the Fock current and the incremental length diffraction coefficient (ILDC) technique. To efficiently calculate the Fock currents, we adopt the numerical contour deformation method. Then, by using the Fock currents and the ILDC technique, high frequency scattered fields are clearly formulated. Compared to the PO scattered fields from the 3-D convex sphere, numerical results demonstrate significant accuracy enhancement of the scattered field via the Fock current.

Electromagnetic Characterization For Graphene By The Peec Method, Ying S. Cao, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

The electromagnetic (EM) features of graphene are characterized by the partial element equivalent circuit (PEEC) model for the first time with an impedance boundary condition. By incorporating the impedance boundary condition into the PEEC model, a novel surface conductivity circuit is proposed for graphene. Furthermore, the definition of the absorption cross section (σabs) and the scattering cross section (σsca) are revisited to make them feasible for PEEC analysis. The application of the impedance boundary condition significantly alleviates the memory consumption and the CPU time. To validate the proposed algorithm, numerical examples are presented and compared with existing references.

Dynamics Of Non-Circular Finite-Release Gravity Currents, ‪Nadim Zgheib, T. Bonometti, S. Balachandar

Mechanical Engineering Faculty Publications

The present work reports some new aspects of non-axisymmetric gravity currents obtained from laboratory experiments, fully resolved simulations and box models. Following the earlier work of Zgheib et al. (Theor. Comput. Fluid Dyn., vol. 28, 2014, pp. 521–529) which demonstrated that gravity currents initiating from non-axisymmetric cross-sectional geometries do not become axisymmetric, nor do they retain their initial shape during the slumping and inertial phases of spreading, we show that such non-axisymmetric currents eventually reach a self-similar regime during which (i) the local front propagation scales as t1/2 as in circular releases and (ii) the non-axisymmetric front has a self-similar …

Successfully Employing Single-Use Bioreactors For Different Expression Systems, Valentin Jossen, Regine Eibl, Dieter Eibl

Single-Use Technologies: Bridging Polymer Science to Biotechnology Applications

The single-use bioreactor market was estimated to have grown at a CAGR of 20% in 2014. Wave-mixed bioreactors and stirred bioreactors represent the largest segment of today`s single-use bioreactor market, and are preferred by process developers and manufacturers of preclinical and clinical samples when high-value products up to medium scale and products requiring high safety demands are in focus. However, wave-mixed and stirred single-use bioreactors are also becoming increasingly important for commercial biopharmaceutical productions. This is ascribed to the availability of high-productivity cell lines, which require smaller bioreactors. In addition, the availability of bioengineering data and cultivation bags with improved …

Single-Use Bioreactor Technologies For Early Stage Development Of Microalgae Cultivation Processes, Gary Lye, Ebenezer Ojo, Hadiza Auta, Frank Baganz

Single-Use Technologies: Bridging Polymer Science to Biotechnology Applications

This work describes the engineering characterization and evaluation of two novel, single-use photobioreactor technologies for microalgal cultivation. There is currently considerable interest in microalgae as alternative expression systems for the production of value-added chemicals as well as therapeutic proteins and vaccines. In contrast to mammalian expression systems, however, bioreactor platforms to address early stage development challenges are not well established particularly for phototrophic and mixotrophic cultivation strategies.

To support early stage cell line selection and process characterization a single-use, 24-well micro photo-bioreactor (mPBr) was established together with an illuminated and environmentally controlled shaker platform [1]. The same orbital shaker platform …

Challenges And Status: Single-Use Bioreactors For Microbial Processes, Peter Neubauer, Anna Maria Marba Ardebol, Friederike Hillig, Olivia Zakrzewski, Jorn Emmerich, N.M.G. Ooosterhuis, S. Junne

Single-Use Technologies: Bridging Polymer Science to Biotechnology Applications

Nowadays single-use bioreactors are fully accepted in the biopharmaceutical industry. Reactors up to 2000L working volume are commonly used. However, these bioreactors are limited in terms of mass-transfer and mixing capabilities and therefore only suited for application in mammalian cell culture. Single-use processing offers many benefits like cost reduction, flexibility, reduction of contamination risks, etc. These benefits apply for both microbial processes as for mammalian processes.

Additionally, for the use of marine microorganisms the application of single-use bioreactors (SUB) offers a possibility to circumvent problem of corrosion which occurs in steel bioreactors due to the high chloride ion concentration in …

Applying Practices From The Medical Device Industry To Ensure Patient Safety Of Single-Use Products In The Biotechnology Industry, Jan Oberdoerster

Single-Use Technologies: Bridging Polymer Science to Biotechnology Applications

Biocompatibility (i.e., the quality of not having toxic or injurious effects on biological systems) requirements for single-use products in the biotechnology industry can vary depending on point of use. For example, single-use syringes are considered a combination medical device and thus require assessment according to the ISO 10993 standards with test ranging from acute systemic toxicity to genotoxicity to sensitization. Processing equipment (e.g., reaction vessels, tubing, filters, chromatography columns) in contrast, generally requires a USP Class VI designation (a battery of in vivo tests consisting of acute systemic toxicity, intracutaneous reactivity, and muscle implantation) with rigorous requirements for leachates. The …

Homogenizing Biologic Drug Substance Bulk Using Single Use Mixing Systems, Benson Gikanga, Yufei Chen, Oliver Stauch, Yuh-Fun Maa

Single-Use Technologies: Bridging Polymer Science to Biotechnology Applications

Mixing of biologic Drug Substance (DS) is a critical process step during manufacturing of biologic Drug Product (DP). Generally, mixers used are equipped with either bottom-mounted or top-mounted agitators. Bottom-mounted mixers (BMMs), particularly those that are magnetically driven, are preferred because of their associated low risk of contamination, ease of use, and ability to accommodate low minimum mixing volumes. Despite these benefits the mechanical coupling of the rotating impeller and the male bearing on the tank may lead to shearing of monoclonal antibody (mAb) formulations generating elevated amount of particles in the DS or DP solution. This may lead to …

Compose: Compacted Object Sample Extraction A Framework For Semi-Supervised Learning In Nonstationary Environments, Karl Dyer

Theses and Dissertations

An increasing number of real-world applications are associated with streaming data drawn from drifting and nonstationary distributions. These applications demand new algorithms that can learn and adapt to such changes, also known as concept drift. Proper characterization of such data with existing approaches typically requires substantial amount of labeled instances, which may be difficult, expensive, or even impractical to obtain. In this thesis, compacted object sample extraction (COMPOSE) is introduced - a computational geometry-based framework to learn from nonstationary streaming data - where labels are unavailable (or presented very sporadically) after initialization. The feasibility and performance of the algorithm are …

Single Use Polymeric Materials: The Science Of Safety, Mitchell Cheeseman

Single-Use Technologies: Bridging Polymer Science to Biotechnology Applications

No abstract provided.