Composition of highly concentrated silicate electrolytes and ultrasound influencing the plasma electrolytic oxidation of magnesium

Science.gov (United States)

Simchen, F.; Rymer, L.-M.; Sieber, M.; Lampke, T.

2017-03-01

Magnesium and its alloys are increasingly in use as lightweight construction materials. However, their inappropriate corrosion and wear resistance often prevent their direct practical use. The plasma electrolytic oxidation (PEO) is a promising, environmentally friendly method to improve the surface characteristics of magnesium materials by the formation of oxide coatings. These PEO layers contain components of the applied electrolyte and can be shifted in their composition by increasing the concentration of the electrolyte constituents. Therefore, in contrast to the use of conventional low concentrated electrolytes, the process results in more stable protective coatings, in which electrolyte species are the dominating constitutes. In the present work, the influence of the composition of highly concentrated alkaline silicate electrolytes with additives of phosphate and glycerol on the quality of PEO layers on the magnesium alloy AZ31 was examined. The effect of ultrasound coupled into the electrolyte bath was also considered. The process was monitored by recording the electrical process variables with a transient recorder and by observation of the discharge phenomena on the sample surface with a camera. The study was conducted on the basis of a design of experiments. The effects of the process parameter variation are considered with regard to the coatings thickness, hardness and corrosion resistance. Information about the statistical significance of the effects of the parameters on the considered properties is obtained by an analysis of variance (ANOVA).

Pulsed nanocrystalline plasma electrolytic boriding as a novel ...

Indian Academy of Sciences (India)

Potentiodynamic polarization and electrochemical impedance spectroscopy were employed to test borided CP-Ti, treated by a relatively new method called pulsed plasma electrolytic boriding. The results show excellent corrosion resistance for modified CP-Ti. The effect of frequency and duty cycle of pulsed current was ...

Research of plasma-electrolyte discharge in the processes of obtaining metallic powders

Science.gov (United States)

Kashapov, R. N.; Kashapov, L. N.; Kashapov, N. F.

2017-11-01

The use of the plasma electrolyte process has never been considered as a simple, cheap and fast method of obtaining powders used in selective laser melting processes. Therefore, the adaptation of the plasma-electrolyte process to the production of metal powders used in additive production is an urgent task. The paper presents the results of studies of gas discharge parameters between a metal and liquid electrode in the processes of obtaining metallic iron powders. The discharge combustion conditions necessary for the formation of metal powders of micron size are determined. A possible mechanism for the formation of powder particles in a discharge plasma is proposed.

XPS and GDOES Characterization of Porous Coating Enriched with Copper and Calcium Obtained on Tantalum via Plasma Electrolytic Oxidation

Directory of Open Access Journals (Sweden)

Krzysztof Rokosz

2016-01-01

Full Text Available XPS and GDOES characterizations of porous coatings on tantalum after Plasma Electrolytic Oxidation (PEO at 450 V for 3 minutes in electrolyte containing concentrated (85% phosphoric acid with calcium nitrate and copper (II nitrate are described. Based on the obtained data, it may be concluded that the PEO coating consists of tantalum (Ta5+, calcium (Ca2+, copper (Cu2+  and Cu+, and phosphates (PO43-. It has to be pointed out that copper and calcium are distributed throughout the volume. The authors also propose a new model of PEO, based on the derivative of GDOES signals with sputtering time.

Effect of hypovolemia, infusion, and oral rehydration on plasma electrolytes, ADH, renin activity, and +G/z/ tolerance

Science.gov (United States)

Greenleaf, J. E.; Brock, P. J.; Haines, R. F.; Rositano, S. A.; Montgomery, L. D.; Keil, L. C.

1977-01-01

Effects on plasma volume, electrolyte shifts, and +G(z) tolerance induced by: (1) blood withdrawal; (2) blood infusion; and (3) oral fluid intake, were determined at 0.5 G/min in centrifugation tests of six ambulatory male patients, aged 21 to 27 yrs. Hypovolemia induced by withdrawal of 400 ml blood, blood infusion followed by repeated centrifugation, effects of consuming an isotonic drink (0.9% NaCl) to achieve oral rehydration, and donning of red adaptation goggles were studied for effects on acceleration tolerance, pre-acceleration and post-acceleration plasma renin activity (PRA) and plasma vasopressin levels. No significant changes in post-acceleration PRA compared to pre-acceleration PRA were found, and administration of oral rehydration is found as effective as blood replacement in counteracting hypovolemic effects.

Plasma electrolytic oxidation of Titanium Aluminides

International Nuclear Information System (INIS)

Morgenstern, R; Sieber, M; Lampke, T; Grund, T; Wielage, B

2016-01-01

Due to their outstanding specific mechanical and high-temperature properties, titanium aluminides exhibit a high potential for lightweight components exposed to high temperatures. However, their application is limited through their low wear resistance and the increasing high-temperature oxidation starting from about 750 °C. By the use of oxide ceramic coatings, these constraints can be set aside and the possible applications of titanium aluminides can be extended. The plasma electrolytic oxidation (PEO) represents a process for the generation of oxide ceramic conversion coatings with high thickness. The current work aims at the clarification of different electrolyte components’ influences on the oxide layer evolution on alloy TNM-B1 (Ti43.5Al4Nb1Mo0.1B) and the creation of compact and wear resistant coatings. Model experiments were applied using a ramp-wise increase of the anodic potential in order to show the influence of electrolyte components on the discharge initiation and the early stage of the oxide layer growth. The production of PEO layers with technically relevant thicknesses close to 100 μm was conducted in alkaline electrolytes with varying amounts of Na 2 SiO 3 ·5H 2 O and K 4 P 2 O 7 under symmetrically pulsed current conditions. Coating properties were evaluated with regard to morphology, chemical composition, hardness and wear resistance. The addition of phosphates and silicates leads to an increasing substrate passivation and the growth of compact oxide layers with higher thicknesses. Optimal electrolyte compositions for maximum coating hardness and thickness were identified by statistical analysis. Under these conditions, a homogeneous inner layer with low porosity can be achieved. The frictional wear behavior of the compact coating layer is superior to a hard anodized layer on aluminum. (paper)

Effect upon biocompatibility and biocorrosion properties of plasma electrolytic oxidation in trisodium phosphate electrolytes.

Science.gov (United States)

Kim, Yu-Kyoung; Park, Il-Song; Lee, Kwang-Bok; Bae, Tae-Sung; Jang, Yong-Seok; Oh, Young-Min; Lee, Min-Ho

2016-03-01

Surface modification to improve the corrosion resistance and biocompatibility of the Mg-Al-Zn-Ca alloy was conducted via plasma electrolytic oxidation (PEO) in an electrolyte that included phosphate. Calcium phosphate can be easily induced on the surface of a PEO coating that includes phosphate in a physiological environment because Ca(2+) ions in body fluids can be combined with PO4 (3-). Cytotoxicity of the PEO coating formed in electrolytes with various amounts of Na3PO4 was identified. In particular, the effects that PEO films have upon oxidative stress and differentiation of osteoblast activity were studied. As the concentration of Na3PO4 in the electrolyte increased, the oxide layer was found to become thicker, which increased corrosion resistance. However, the PEO coating formed in electrolytes with over 0.2 M of added Na3PO4 exhibited more microcracks and larger pores than those formed in smaller Na3PO4 concentrations owing to a large spark discharge. A nonuniform oxide film that included more phosphate caused more cytotoxicity and oxidative stress, and overabundant phosphate content in the oxide layer interrupted the differentiation of osteoblasts. The corrosion resistance of the magnesium alloy and the thickness of the oxide layer were increased by the addition of Na3PO4 in the electrolyte for PEO treatment. However, excessive phosphate content in the oxide layer led to oxidative stress, which resulted in reduced cell viability and activity.

Plasma electrolytic liquefaction of cellulosic biomass

Science.gov (United States)

Dingliang, TANG; Xianhui, ZHANG; Si-ze, YANG

2018-04-01

In this paper, the rapid liquefaction of a corncob was achieved by plasma electrolysis, providing a new method for cellulosic biomass liquefaction. The liquefaction rate of the corncob was 95% after 5 min with polyethylene glycol and glycerol as the liquefying agent. The experiments not only showed that H+ ions catalyzed the liquefaction of the corncob, but also that using accelerated H+ ions, which were accelerated by an electric field, could effectively improve the liquefaction efficiency. There was an obvious discharge phenomenon, in which the generated radicals efficiently heated the solution and liquefied the biomass, in the process of plasma electrolytic liquefaction. Finally, the optimum parameters of the corncob liquefaction were obtained by experimentation, and the liquefaction products were analyzed.

Role of electrolyte composition on structural, morphological and in-vitro biological properties of plasma electrolytic oxidation films formed on zirconium

International Nuclear Information System (INIS)

M, Sandhyarani; T, Prasadrao; N, Rameshbabu

2014-01-01

Highlights: • Uniform oxide films were formed on zirconium by plasma electrolytic oxidation. • Silicate in electrolyte alter the growth of m-ZrO 2 from (1 ¯ 11) to (2 0 0) orientation. • Addition of KOH to electrolyte improved the corrosion resistance of oxide films. • Silicon incorporated oxide films showed higher surface roughness and wettability. • Human osteosarcoma cells were strongly adhered and spreaded on all the oxide films. - Abstract: Development of oxide films on metallic implants with a good combination of corrosion resistance, bioactivity and cell adhesion can greatly improve its biocompatibility and functionality. Thus, the present work is aimed to fabricate oxide films on metallic Zr by plasma electrolytic oxidation (PEO) in methodically varied concentrations of phosphate, silicate and KOH based electrolyte systems using a pulsed DC power source. The oxide films fabricated on Zr are characterized for its phase composition, surface morphology, chemical composition, roughness, wettability, surface energy, corrosion resistance, apatite forming ability and osteoblast cell adhesion. Uniform films with thickness varying from 6 to 11 μm are formed. XRD patterns of all the PEO films showed the predominance of monoclinic zirconia phase. The film formed in phosphate + KOH electrolyte showed superior corrosion resistance, which can be ascribed to its pore free morphology. The films formed in silicate electrolyte showed higher apatite forming ability with good cell adhesion and spreading over its surface which is attributed to its superior surface roughness and wettability characteristics. Among the five different electrolyte systems employed in the present study, the PEO film formed in an electrolyte system with phosphate + silicate + KOH showed optimum corrosion resistance, apatite forming ability and biocompatibility

Solid polymer electrolyte composite membrane comprising plasma etched porous support

Science.gov (United States)

Liu, Han; LaConti, Anthony B.

2010-10-05

A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a rigid, non-electrically-conducting support, the support preferably being a sheet of polyimide having a thickness of about 7.5 to 15 microns. The support has a plurality of cylindrical pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores, which preferably have a diameter of about 0.1 to 5 microns, are made by plasma etching and preferably are arranged in a defined pattern, for example, with fewer pores located in areas of high membrane stress and more pores located in areas of low membrane stress. The pores are filled with a first solid polymer electrolyte, such as a perfluorosulfonic acid (PFSA) polymer. A second solid polymer electrolyte, which may be the same as or different than the first solid polymer electrolyte, may be deposited over the top and/or bottom of the first solid polymer electrolyte.

Plasma electrolytic oxidation of metals

Directory of Open Access Journals (Sweden)

Stojadinović Stevan

2013-01-01

Full Text Available In this lecture results of the investigation of plasma electrolytic oxidation (PEO process on some metals (aluminum, titanium, tantalum, magnesium, and zirconium were presented. Whole process involves anodizing metals above the dielectric breakdown voltage where numerous micro-discharges are generated continuously over the coating surface. For the characterization of PEO process optical emission spectroscopy and real-time imaging were used. These investigations enabled the determination of electron temperature, electron number density, spatial density of micro-discharges, the active surface covered by micro-discharges, and dimensional distribution of micro-discharges at various stages of PEO process. Special attention was focused on the results of the study of the morphology, chemical, and phase composition of oxide layers obtained by PEO process on aluminum, tantalum, and titanium in electrolytes containing tungsten. Physicochemical methodes: atomic force microscopy (AFM, scanning electron microscopy (SEM-EDS, x-ray diffraction (XRD, x-ray photoelectron spectroscopy (XPS, and Raman spectroscopy served as tools for examining obtained oxide coatings. Also, the application of the obtained oxide coatings, especially the application of TiO2/WO3 coatings in photocatalysis, were discussed.

Preparation and corrosion resistance of a nanocomposite plasma electrolytic oxidation coating on Mg-1%Ca alloy formed in aluminate electrolyte containing titania nano-additives

DEFF Research Database (Denmark)

Daroonparvar, Mohammadreza; Yajid, M. A. M.; Yusof, N. M.

2016-01-01

Titania nanoparticles were utilized as suspension in alkaline aluminate electrolyte to form nanocomposite coatings on magnesium alloy containing 1 wt% calcium by plasma electrolytic oxidation process. Microhardness, wettability, potentiodynamic polarization, wettability, electrochemical impedance...

Characterization of metal-supported axial injection plasma sprayed solid oxide fuel cells with aqueous suspension plasma sprayed electrolyte layers

Science.gov (United States)

Waldbillig, D.; Kesler, O.

A method for manufacturing metal-supported SOFCs with atmospheric plasma spraying (APS) is presented, making use of aqueous suspension feedstock for the electrolyte layer and dry powder feedstock for the anode and cathode layers. The cathode layer was deposited first directly onto a metal support, in order to minimize contact resistance, and to allow the introduction of added porosity. The electrolyte layers produced by suspension plasma spraying (SPS) were characterized in terms of thickness, permeability, and microstructure, and the impact of substrate morphology on electrolyte properties was investigated. Fuel cells produced by APS were electrochemically tested at temperatures ranging from 650 to 750 °C. The substrate morphology had little effect on open circuit voltage, but substrates with finer porosity resulted in lower kinetic losses in the fuel cell polarization.

Characterization of metal-supported axial injection plasma sprayed solid oxide fuel cells with aqueous suspension plasma sprayed electrolyte layers

Energy Technology Data Exchange (ETDEWEB)

Waldbillig, D. [University of British Columbia, Department of Materials Engineering, 309-6350 Stores Road, Vancouver, BC (Canada); Kesler, O. [University of Toronto, Department of Mechanical and Industrial Engineering, 5 King' s College Road, Toronto, Ontario (Canada)

2009-06-15

A method for manufacturing metal-supported SOFCs with atmospheric plasma spraying (APS) is presented, making use of aqueous suspension feedstock for the electrolyte layer and dry powder feedstock for the anode and cathode layers. The cathode layer was deposited first directly onto a metal support, in order to minimize contact resistance, and to allow the introduction of added porosity. The electrolyte layers produced by suspension plasma spraying (SPS) were characterized in terms of thickness, permeability, and microstructure, and the impact of substrate morphology on electrolyte properties was investigated. Fuel cells produced by APS were electrochemically tested at temperatures ranging from 650 to 750 C. The substrate morphology had little effect on open circuit voltage, but substrates with finer porosity resulted in lower kinetic losses in the fuel cell polarization. (author)

Effect of substrate and cathode parameters on the properties of suspension plasma sprayed solid oxide fuel cell electrolytes

Energy Technology Data Exchange (ETDEWEB)

Waldbillig, D.; Tang, Z.; Burgess, A. [British Columbia Univ., Vancouver, BC (Canada); Kesler, O. [Toronto Univ., ON (Canada)

2008-07-01

An axial injection suspension plasma spray system has been used to produce layers of fully stabilized yttriastabilized zirconia (YSZ) that could be used as solid oxide fuel cell (SOFC) electrolytes. Suspension plasma spraying is a promising technique for the rapid production of coatings with fine microstructures and controlled porosity without requiring a post-deposition heat treatment. This new manufacturing technique to produce SOFC active layers requires the build up of a number of different plasma sprayed SOFC functional layers (cathode, electrolyte and anode) sequentially on top of each other. To understand the influence of the substrate and previouslydeposited coating layers on subsequent coating layer properties, YSZ layers were deposited on top of plasma sprayed composite lanthanum strontium manganite (LSM)/YSZ cathode layers that were first deposited on porous ferritic stainless steel substrates. Three layer half cells consisting of the porous steel substrate, composite cathode, and suspension plasma sprayed electrolyte layer were then characterized. A systematic study was performed in order to investigate the effect of parameters such as substrate and cathode layer roughness, substrate surface pore size, and cathode microstructure and thickness on electrolyte deposition efficiency, cathode and electrolyte permeability, and layer microstructure. (orig.)

Electrochemical corrosion behaviour of plasma electrolytic oxidation coatings on AM50 magnesium alloy formed in silicate and phosphate based electrolytes

International Nuclear Information System (INIS)

Liang, J.; Srinivasan, P. Bala; Blawert, C.; Stoermer, M.; Dietzel, W.

2009-01-01

PEO coatings were produced on AM50 magnesium alloy by plasma electrolytic oxidation process in silicate and phosphate based electrolytes using a pulsed DC power source. The microstructure and composition of the PEO coatings were analyzed by scanning electron microscopy (SEM) and X-ray Diffraction (XRD). The corrosion resistance of the PEO coatings was evaluated using open circuit potential (OCP) measurements, potentiodynamic polarisation tests and electrochemical impedance spectroscopy (EIS) in 0.1 M NaCl solution. It was found that the electrolyte composition has a significant effect on the coating evolution and on the resulting coating characteristics, such as microstructure, composition, coating thickness, roughness and thus on the corrosion behaviour. The corrosion resistance of the PEO coating formed in silicate electrolyte was found to be superior to that formed in phosphate electrolyte in both the short-term and long-term electrochemical corrosion tests.

Partial and apparent molar volumes of aqueous solutions of the 1:1 type electrolytes

International Nuclear Information System (INIS)

Klugman, I.Yu.

2002-01-01

Formulas for calculating partial and apparent molar volumes of MX (M=Li-Cs; X = Cl-I) electrolyte aqueous solutions in a wide range of concentrations from 0 to 4 mol/kg with error not in excess of 0.05% are suggested. It is shown that the previously employed formulas for calculating partial molar volumes of electrolytes give false indications of mutual effect of ions and actually they are fit solely for very small concentrations [ru

Effects of electrolytes variation on formation of oxide layers of 6061 Al alloys by plasma electrolytic oxidation

Institute of Scientific and Technical Information of China (English)

Kai WANG; Bon-Heun KOO; Chan-Gyu LEE; Young-Joo KIM; Sung-Hun LEE; Eungsun BYON

2009-01-01

Plasma electrolytic oxidation(PEO) processes were carried out to produce ceramic layers on 6061 aluminum substrates in four kinds of electrolytes such as silicate and aluminate solution with and without sodium fluorosilicate. The PEO processes were carried out under a hybrid voltage (260 V DC combined with 200 V, 60 Hz AC amplitude) at room temperature for 5 min. The composition, microstructure and element distribution analyses of the PEO-treated layers were carried out by XRD and SEM & EDS. The effect of the electrolyte contents on the growth mechanism, element distribution and properties of oxide layers were studied. It is obvious that the layers generated in aluminate solutions show smoother surfaces than those in silicate solutions. Moreover, an addition of fluorine ion can effectively control the layer porosity; therefore, it can enhance the properties of the layers.

AC plasma electrolytic oxidation of magnesium with zirconia nanoparticles

International Nuclear Information System (INIS)

Arrabal, R.; Matykina, E.; Viejo, F.; Skeldon, P.; Thompson, G.E.; Merino, M.C.

2008-01-01

The incorporation of monoclinic zirconia nanoparticles and their subsequent transformation is examined for coatings formed on magnesium by plasma electrolytic oxidation under AC conditions in silicate electrolyte. The coatings are shown to comprise two main layers, with nanoparticles entering the coating at the coating surface and through short-circuit paths to the region of the interface between the inner and outer coating layers. Under local heating of microdischarges, the zirconia reacts with magnesium species to form Mg 2 Zr 5 O 12 in the outer coating layer. Relatively little zirconium is present in the inner coating layer. In contrast, silicon species are present in both coating layers, with reduced amounts in the inner layer

Discharge behaviors during plasma electrolytic oxidation on aluminum alloy

International Nuclear Information System (INIS)

Liu, Run; Wu, Jie; Xue, Wenbin; Qu, Yao; Yang, Chaolin; Wang, Bin; Wu, Xianying

2014-01-01

A plasma electrolytic oxidation (PEO) process was performed on the 2024 aluminum alloy in silicate electrolyte to fabricate ceramic coatings under a constant voltage. Optical emission spectroscopy (OES) was employed to evaluate the characteristics of plasma discharge during PEO process. The plasma electron temperature and density were obtained by analyzing the spectral lines of OES, and the atomic ionization degree in discharge zone was calculated in terms of Saha thermal ionization equation. The illumination intensity of plasma discharge and the temperature in the interior of alloy were measured. Combining the surface morphology and cross-sectional microstructure with the optical emission spectra and illumination at different discharge stage, a discharge model in the growth of PEO ceramic coatings was proposed. It is found that there are two discharge modes of type A with small spark size and type B with large spark size, and the latter only appears in the intermediate stage of PEO process. The illumination intensity has a maximum value in the initial stage of oxidation with many sparks of discharge type A. The electron temperature in plasma discharge zone is about 3000 K–7000 K and atomic ionization degree of Al is about 2.0 × 10 −5 –7.2 × 10 −3 , which depend on discharge stage. The discharge type B plays a key role on the electron temperature and atomic ionization degree. The electron density keeps stable in the range of about 8.5 × 10 21  m −3 –2.6 × 10 22  m −3 . - Highlights: • The characteristics of PEO plasma discharge was evaluated by OES. • Electron temperature, concentration, atomic ionization degree were calculated. • Discharge model for the growth of PEO coatings was proposed. • Temperature in the interior of alloy during PEO process was measured

Factors Influencing Plasma Electrolytic Oxidation(PEO) Coatings on Magnesium Alloys: A Review

Energy Technology Data Exchange (ETDEWEB)

Shim, Gunchoo [KISTI ReSEAT Program, Daejon (Korea, Republic of)

2017-05-15

Magnesium alloys, which possess excellent specific strength and castability, are highly susceptible to corrosion. Although anodizing is widely used to resolve this problem, it requires toxic electrolytes and produces relatively thin and weak surface coatings. Recently, plasma electrolytic oxidation (PEO) has emerged as an alternative to anodizing. Although it is derived from conventional anodizing, it uses eco-friendly electrolytes and forms thicker, denser, and harder coatings on the surface of magnesium alloys. However, PEO is a complex process involving physical, chemical, and electrochemical reactions, and it is influenced by various factors such as the alloy substrate composition, electrolyte/additive composition, and the electrical variables including the mode of power supply, applied voltage/current density, frequency, and duty cycle. In this article, the detailed effects of these parameters on the microstructure and properties of the PEO coatings are reviewed, and methods of improving the coatings are proposed.

Plasma electrolytes in patients with asthma in a tertiary hospital in ...

African Journals Online (AJOL)

Background: We compared plasma electrolytes in patients with and without asthma. Methods: Subjects for the study comprised of 17 male and 45 female asthmatics attending the Chest Clinic of the University of Benin Teaching Hospital (UBTH), Benin City, Nigeria. These patients had questionnaires administered and the ...

Enhanced mechanical properties and increased corrosion resistance of a biodegradable magnesium alloy by plasma electrolytic oxidation (PEO)

International Nuclear Information System (INIS)

White, Leon; Koo, Youngmi; Neralla, Sudheer; Sankar, Jagannathan; Yun, Yeoheung

2016-01-01

Highlights: • Plasma electrolytic oxidation (PEO) method was developed to control corrosion, porosity, and mechanical property. • Mechanical properties of PEO-coated AZ31 alloys were affected by the different electrolyte. • Mechanical properties and corrosion resistance of PEO-coated AZ31 alloys were compared with uncoated one. - Abstract: We report the enhanced mechanical properties of AZ31 magnesium alloys by plasma electrolytic oxidation (PEO) coating in NaOH, Na_2SiO_3, KF and NaH_2PO_4·2H_2O containing electrolytes. Mechanical properties including wear resistance, surface hardness and elastic modulus were increased for PEO-coated AZ31 Mg alloys (PEO-AZ31). DC polarization in Hank's solution indicating that the corrosion resistance significantly increased for PEO-coating in KF-contained electrolyte. Based on these results, the PEO coating method shows promising potential for use in biodegradable implant applications where tunable corrosion and mechanical properties are needed.

Enhanced mechanical properties and increased corrosion resistance of a biodegradable magnesium alloy by plasma electrolytic oxidation (PEO)

Energy Technology Data Exchange (ETDEWEB)

White, Leon; Koo, Youngmi [FIT BEST Laboratory, Engineering Research Center, Department of Chemical, Biological, and Bio Engineering, North Carolina A& T State University, Greensboro, NC 27411 (United States); Neralla, Sudheer [Jet-Hot LLC, Burlington, NC 27215 (United States); Sankar, Jagannathan [FIT BEST Laboratory, Engineering Research Center, Department of Chemical, Biological, and Bio Engineering, North Carolina A& T State University, Greensboro, NC 27411 (United States); Yun, Yeoheung, E-mail: yyun@ncat.edu [FIT BEST Laboratory, Engineering Research Center, Department of Chemical, Biological, and Bio Engineering, North Carolina A& T State University, Greensboro, NC 27411 (United States)

2016-06-15

Highlights: • Plasma electrolytic oxidation (PEO) method was developed to control corrosion, porosity, and mechanical property. • Mechanical properties of PEO-coated AZ31 alloys were affected by the different electrolyte. • Mechanical properties and corrosion resistance of PEO-coated AZ31 alloys were compared with uncoated one. - Abstract: We report the enhanced mechanical properties of AZ31 magnesium alloys by plasma electrolytic oxidation (PEO) coating in NaOH, Na{sub 2}SiO{sub 3}, KF and NaH{sub 2}PO{sub 4}·2H{sub 2}O containing electrolytes. Mechanical properties including wear resistance, surface hardness and elastic modulus were increased for PEO-coated AZ31 Mg alloys (PEO-AZ31). DC polarization in Hank's solution indicating that the corrosion resistance significantly increased for PEO-coating in KF-contained electrolyte. Based on these results, the PEO coating method shows promising potential for use in biodegradable implant applications where tunable corrosion and mechanical properties are needed.

Designing advanced materials by environmental friendly plasma electrolytic oxidation

International Nuclear Information System (INIS)

Toader, I.; Valeca, M.; Rusu, O.; Coaca, E.; Marin, A.

2016-01-01

In the CANDU-PHWR nuclear reactors, Zr-2.5Nb coated with a black adherent oxide film of 1 to 2 μm in thickness is currently used for the manufacture of pressure tubes. The black oxide thin film has corrosion protective properties. However, it can be damaged during the regular refueling process, thus causing hydrogen/oxygen ingression. Therefore, an enhanced wear and corrosion resistance coating is needed. Plasma electrolytic oxidation (PEO) is an anodic electrochemical treatment, both cost-effective and environmentally friendly, widely used in the formation of a protective oxide film on the metal surface to enhance wear and corrosion resistance as well as prolonging component lifetime. The state of the art reveals that PEO method is suitable for improving the wear resistance of Zr-2.5Nb alloy. Few studies are performed in this field and thus, it is necessary to conduct a more detailed insight study on the processing parameters for PEO treatment. By understanding the influence of process parameters, such as electrolyte temperature and electrolyte composition, we can find the way to obtain a coating with improved mechanical and corrosion properties on zirconium alloys. (authors)

Non-electrolytic synthesis of copper oxide/carbon nanocomposite by surface plasma in super-dehydrated ethanol

Science.gov (United States)

Kozak, Dmytro S.; Sergiienko, Ruslan A.; Shibata, Etsuro; Iizuka, Atsushi; Nakamura, Takashi

2016-02-01

Electrolytic processes are widely used to synthesize different nanomaterials and it does not depend on what kind of the method has been applied (wet-chemistry, sonochemistry, plasma chemistry, electrolysis and so on). Generally, the reactions in the electrolyte are considered to be reduction/oxidation (REDOX) reactions between chemical reagents or the deposition of matter on the electrodes, in line with Faraday’s law. Due to the presence of electroconductive additives in any electrolyte, the polarization effect of polar molecules conducting an electrical current disappears, when external high-strength electric field is induced. Because initially of the charge transfer always belongs of electroconductive additive and it does not depend on applied voltage. The polarization of ethanol molecules has been applied to conduct an electric current by surface plasma interaction for the synthesis of a copper oxide/carbon nanocomposite material.

Plasma volume changes during hypoglycaemia

DEFF Research Database (Denmark)

Hilsted, J; Frandsen, Henrik Lund; Christensen, N J

1991-01-01

-induced hypoglycaemia with total autonomic blockade (alpha-adrenoceptor blockade combined with beta-adrenoceptor blockade and atropine); and insulin-induced hypoglycaemia without any autonomic blockade. In the experiments without autonomic blockade the peripheral venous hematocrit increased, plasma volume decreased......, intravascular albumin content decreased and the transcapillary escape rate of albumin increased. In both experiments with autonomic blockade the increase in venous haematocrit was abolished, yet plasma volume decreased, intravascular albumin content decreased and the transcapillary escape rate of albumin...... increased in these experiments. Thus, the changes in plasma volume and composition in response to hypoglycaemia are due to the combined actions of adrenaline and of insulin....

Mg-containing hydroxyapatite coatings produced by plasma electrolytic oxidation of titanium

Energy Technology Data Exchange (ETDEWEB)

Antonio, Cesar Augusto; Rangel, Elidiane Cipriano; Durrant, Steven Frederick; Cruz, Nilson Cristino da, E-mail: cesar.augustoa@hotmail.com [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Sorocaba, SP (Brazil). Lab. de Plasmas Tecnologicos; Delgado-Silva, Adriana de Oliveira [Universidade Federal de Sao Carlos (UFSCar), Sorocaba, SP (Brazil); Tabacniks, Manfredo H. [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Fisica

2017-07-15

Plasma Electrolytic Oxidation (PEO) is promising for the processing of biomaterials because it enables the production of surfaces with adjustable composition and structure. In this work, aimed at the improvement of the bioactivity of titanium, PEO has been used to grow calcium phosphide coatings on titanium substrates. The effects of the addition of magnesium acetate to the electrolytes on the composition of the coatings produced during 120 s on Ti disks using bipolar voltage pulses and solutions of calcium and magnesium acetates and sodium glycerophosphate as electrolytes have been studied. Scanning electron microscopy, X-ray energy dispersive spectroscopy, Rutherford backscattering spectroscopy, X-ray diffractometry with Rietveld refinement and profilometry were used to characterize the modified samples. Coatings composed of nearly 50 % of Mg-doped hydroxyapatite have been produced. In certain conditions up to 4% Mg can be incorporated into the coating without any observable significant structural modifications of the hydroxyapatite. (author)

Formation of a Spinel Coating on AZ31 Magnesium Alloy by Plasma Electrolytic Oxidation

Science.gov (United States)

Sieber, Maximilian; Simchen, Frank; Scharf, Ingolf; Lampke, Thomas

2016-03-01

Plasma electrolytic oxidation (PEO) is a common means for the surface modification of light metals. However, PEO of magnesium substrates in dilute electrolytes generally leads to the formation of coatings consisting of unfavorable MgO magnesium oxide. By incorporation of electrolyte components, the phase constitution of the oxide coatings can be modified. Coatings consisting exclusively of MgAl2O4 magnesium-aluminum spinel are produced by PEO in an electrolyte containing hydroxide, aluminate, and phosphate anions. The hardness of the coatings is 3.5 GPa on Martens scale on average. Compared to the bare substrate, the coatings reduce the corrosion current density in dilute sodium chloride solution by approx. one order of magnitude and slightly shift the corrosion potential toward more noble values.

Fluid-electrolyte shifts and thermoregulation - Rest and work in heat with head cooling

Science.gov (United States)

Greenleaf, J. E.; Van Beaumont, W.; Brock, P. J.; Montgomery, L. D.; Morse, J. T.; Shvartz, E.; Kravik, S.

1980-01-01

The effects of head cooling on thermoregulation and associated plasma fluid and electrolyte shifts during rest and submaximal exercise in the heat are investigated. Thermoregulatory responses and plasma volume were measured in four male subjects fitted with liquid-cooled neoprene headgear during 60 min of rest, 60 min of ergometer exercise at 45% maximal oxygen uptake and 30 min of recovery in the supine position at 40.1 C and 40% relative humidity. It is found that, compared to control responses, head cooling decreased thigh sweating and increased mean skin temperature at rest and attenuated increases in thigh sweating, heart rate, rectal temperature and ventilation during exercise. During recovery, cooling is observed to facilitate decreases in sweat rate, heart rate, rectal temperature and forearm blood flow and enhance the increase in average temperature. Cooling had no effect on plasma protein, osmotic or electrolyte shifts, and decreased plasma volume losses. The findings indicate the effectiveness of moderate head cooling for the improvement of human performance during exercise in heat.

In situ formation of low friction ceramic coatings on carbon steel by plasma electrolytic oxidation in two types of electrolytes

International Nuclear Information System (INIS)

Wang Yunlong; Jiang Zhaohua

2009-01-01

In situ formation of ceramic coatings on Q235 carbon steel was achieved by plasma electrolytic oxidation (PEO) in carbonate electrolyte and silicate electrolyte, respectively. The surface and cross-section morphology, phase and elemental composition of PEO coatings were examined by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS). The bond strength of the coating was determined using a direct pull-off test. The hardness as well as tribological properties of the ceramic coating was primarily studied. The results indicated that the coating obtained in carbonate electrolyte was Fe 3 O 4 , while the coating achieved from silicate electrolyte was proved to be amorphous. Both kinds of coatings showed coarse and porous surface. The Fe 3 O 4 coatings obtained in carbonate electrolyte showed a high bonding strength to the substrate up to 20 ± 2 MPa and the value was 15 ± 2 MPa for the amorphous coatings obtained in carbonate electrolyte. The micro hardness of the amorphous coating and the Fe 3 O 4 coating was 1001 Hv and 1413 Hv, respectively, which was more than two and three times as that of the Q235 alloy substrate (415 Hv). The friction coefficient exhibited by amorphous coating and Fe 3 O 4 coating was 0.13 and 0.11, respectively, both lower than the uncoated Q235 substrate which ranged from 0.17 to 0.35.

Dose related anxiolytic effects of diazepam: relation with serum electrolytes, plasma osmolality and systolic blood pressure (sbp) in rats

International Nuclear Information System (INIS)

Farooq, R.; Haleem, D.J.; Haleem, M.A.

2008-01-01

Diazepam is an anxiolytic and anticonvulsant drug that also induces hypnosis. Changes in serum electrolyte balance, plasma osmolality and systolic blood pressure (SBP) are often associated with stress-induced anxiety. Administration of diazepam has been show to decrease stress-induced enhancement of hypothalamic pituitary adrenal cortical (HPA) axis. The present is designed to monitor the anxiolytic effects of different doses of diazepam (1 mg/kg, 2.5 mg/kg and 5 mg/kg) and its association with changes of serum electrolyte balance, plasma osmolality and SBP in rats. Administration of diazepam at doses of 1 mg/kg, 2.5 mg/kg and 5 mg/kg elicited anxiolytic effects monitored in light-dark transition test and increased serum concentration of electrolytes and plasma osmolality. Serum levels of magnesium as well as SBP decreased. The results are discussed in context of anxiolytic effects of diazepam to be mediated via a modulation of stress-induced increase in the activity of HPA-axis arid electrolytes balance. (author)

Spectroscopic study of plasma during electrolytic oxidation of magnesium- and aluminium-alloy

International Nuclear Information System (INIS)

Jovović, J.; Stojadinović, S.; Šišović, N.M.; Konjević, N.

2012-01-01

We present the results of an optical emission spectroscopy study of Plasma during Electrolytic Oxidation (PEO) of magnesium- and aluminum-alloy. Plasma electron number density N e diagnostics is performed either from the H β line shape or from the width or shift of non-hydrogenic ion lines of aluminum and magnesium. The line profile analysis of the H β suggests presence of two PEO processes characterized by relatively low electron number densities N e ≈1.2×10 15 cm −3 and N e ≈2.3×10 16 cm −3 . Apart from these two low N e processes, there is the third one related to the ejection of evaporated anode material through micro-discharge channels. This process is characterized by larger electron density N e =(1.2–1.6)10 17 cm −3 , which is detected from the shape and shift of aluminum and magnesium singly charged ion lines. Two low N e values detected from the H β and large N e measured from the widths and shift of ion lines suggest presence of three types of discharges during PEO with aluminum- and magnesium-alloy anode. On the basis of present and earlier results one can conclude that low N e processes do not depend upon anode material or electrolyte composition. The electron temperature of 4000 K and 33,000 K are determined from relative intensities of Mg I and O II lines, respectively. The attention is drawn to the possibility of N e application for T e evaluation using Saha equation what is of importance for PEO metal plasma characterization. During the course of this study, difficulties in the analysis of spectral line shapes are encountered and the ways to overcome some of the obstacles are demonstrated. -- Highlights: ► Optical emission spectroscopy of plasma during electrolytic oxidation. ► Spectral line profiles of the H-beta and non-hydrogenic singly charged ion lines of aluminum and magnesium. ► Experimental line profiles with complex structure. ► Three plasma processes involved. ► The application of Saha equation for the process

Systematic understanding of corrosion behavior of plasma electrolytic oxidation treated AZ31 magnesium alloy using a mouse model of subcutaneous implant

Energy Technology Data Exchange (ETDEWEB)

Jang, Yongseok [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC, 27411 (United States); Tan, Zongqing [Internal Medicine, College of Medicine, University of Cincinnati, OH 45211 (United States); Jurey, Chris [Luke Engineering, Wadsworth, OH 44282 (United States); Collins, Boyce [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC, 27411 (United States); Badve, Aditya [Business and Biology, The University of North Carolina at Chapel Hill, NC 27514 (United States); Dong, Zhongyun [Internal Medicine, College of Medicine, University of Cincinnati, OH 45211 (United States); Park, Chanhee; Kim, Cheol Sang [Department of Bio-nano System Engineering, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Sankar, Jagannathan [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC, 27411 (United States); Yun, Yeoheung, E-mail: yyun@ncat.edu [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC, 27411 (United States)

2014-12-01

This study was conducted to identify the differences between corrosion rates, corrosion types, and corrosion products in different physiological environments for AZ31 magnesium alloy and plasma electrolytic oxidation (PEO) treated AZ31 magnesium alloy. In vitro and in vivo tests were performed in Hank's Balanced Salt Solution (HBSS) and mice for 12 weeks, respectively. The corrosion rates of both AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy were calculated based on DC polarization curves, volume of hydrogen evolution, and the thickness of corrosion products formed on the surface. Micro X-ray computed tomography (Micro-CT), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) were used to analyze morphological and chemical characterizations of corrosion products. The results show that there is more severe localized corrosion after in vitro test in HBSS; however, the thicknesses of corrosion products formed on the surface for AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy in vivo were about 40% thicker than the thickness of corrosion products generated in vitro. The ratio of Ca and P (Ca/P) in the corrosion products also differed. The Ca deficient region and higher content of Al in corrosion product than AZ31 magnesium alloy were identified after in vivo test in contrast with the result of in vitro test. - Highlights: • Effects of plasma electrolytic oxidation on AZ31 in vitro and in vivo • Retardation of degradation via plasma electrolytic oxidation in vitro and in vivo • Differentiation of in vitro and in vivo corrosion types and products.

Systematic understanding of corrosion behavior of plasma electrolytic oxidation treated AZ31 magnesium alloy using a mouse model of subcutaneous implant

International Nuclear Information System (INIS)

Jang, Yongseok; Tan, Zongqing; Jurey, Chris; Collins, Boyce; Badve, Aditya; Dong, Zhongyun; Park, Chanhee; Kim, Cheol Sang; Sankar, Jagannathan; Yun, Yeoheung

2014-01-01

This study was conducted to identify the differences between corrosion rates, corrosion types, and corrosion products in different physiological environments for AZ31 magnesium alloy and plasma electrolytic oxidation (PEO) treated AZ31 magnesium alloy. In vitro and in vivo tests were performed in Hank's Balanced Salt Solution (HBSS) and mice for 12 weeks, respectively. The corrosion rates of both AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy were calculated based on DC polarization curves, volume of hydrogen evolution, and the thickness of corrosion products formed on the surface. Micro X-ray computed tomography (Micro-CT), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) were used to analyze morphological and chemical characterizations of corrosion products. The results show that there is more severe localized corrosion after in vitro test in HBSS; however, the thicknesses of corrosion products formed on the surface for AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy in vivo were about 40% thicker than the thickness of corrosion products generated in vitro. The ratio of Ca and P (Ca/P) in the corrosion products also differed. The Ca deficient region and higher content of Al in corrosion product than AZ31 magnesium alloy were identified after in vivo test in contrast with the result of in vitro test. - Highlights: • Effects of plasma electrolytic oxidation on AZ31 in vitro and in vivo • Retardation of degradation via plasma electrolytic oxidation in vitro and in vivo • Differentiation of in vitro and in vivo corrosion types and products

Changes in mechanical properties and structure of electrolytic plasma treated X 12 CrNi 18 10 Ti stainless steel

Energy Technology Data Exchange (ETDEWEB)

Kurbanbekov, Sherzod; Baklanov, Viktor; Karakozov, Batyrzhan [Republican State Enterprise National Nuclear Center of Kazakhstan, Kurchatov (Kazakhstan). Inst. of Atomic Energy Branch; Skakov, Mazhyn [Republican State Enterprise National Nuclear Center of Kazakhstan, Kurchatov (Kazakhstan)

2017-05-01

The paper addresses findings regarding the influence of electrolytic plasma treatment on the mechanical properties as well as structural and phase states of X 12 CrNi 18 10 Ti steel. Electrolytic plasma treatment is based on carburizing of stainless steel heated in electrolytes. Treatment of steel samples has been performed as follows: the samples were heated up to a temperature between 850 and 950 C and then they were cured for 7 minutes in an electrolyte of an aqueous solution containing 10 % glycerol (C{sub 3}H{sub 8}O{sub 3}) and 15 % sodium carbonate (Na{sub 2}CO{sub 3}). It is found that, after plasma electrolytic treatment, the surface of X 12 CrNi 18 10 Ti steel had a modified structure and high hardness. Increasing wear resistance of X 12 CrNi 18 10 Ti steel has been observed after carburizing and the coefficient of friction has been reduced. X-ray analysis showed that retained austenite γ-Fe is a main phase, and there are some diffraction lines of orthorhombic Fe{sub 3}C phase as well as Fe{sub 3}O{sub 4} cubic phase. It has been determined, that, after plasma electrolytic treatment, a carbide phase in the modified surface layer, irrespective of the location in the steel structure has the chemical composition Fe{sub 3}C. High concentration of carbon atoms in a solid solution based on γ- and α-iron, a large dislocation density, presence of particles of carbide phase and retained austenite layers have been found.

TiO2 Deposition on AZ31 Magnesium Alloy Using Plasma Electrolytic Oxidation

Directory of Open Access Journals (Sweden)

Leon White

2013-01-01

Full Text Available Plasma electrolytic oxidation (PEO has been used in the past as a useful surface treatment technique to improve the anticorrosion properties of Mg alloys by forming protective layer. Coatings were prepared on AZ31 magnesium alloy in phosphate electrolyte with the addition of TiO2 nanoparticles using plasma electrolytic oxidation (PEO. This present work focuses on developing a TiO2 functional coating to create a novel electrophotocatalyst while observing the surface morphology, structure, composition, and corrosion resistance of the PEO coating. Microstructural characterization of the coating was investigated by X-ray diffraction (XRD and scanning electron microscopy (SEM followed by image analysis and energy dispersive spectroscopy (EDX. The corrosion resistance of the PEO treated samples was evaluated with electrochemical impedance spectroscopy (EIS and DC polarization tests in 3.5 wt.% NaCl. The XRD pattern shows that the components of the oxide film include Mg from the substrate as well as MgO and Mg2TiO4 due to the TiO2 nanoparticle addition. The results show that the PEO coating with TiO2 nanoparticles did improve the corrosion resistance when compared to the AZ31 substrate alloy.

Plasma volume changes during hypoglycaemia

DEFF Research Database (Denmark)

Hilsted, J; Bendtsen, F; Christensen, N J

1990-01-01

To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... of albumin in arterial and venous blood in seven healthy subjects before and during insulin-induced hypoglycaemia. In both vascular sites blood 51Cr content and the haematocrit increased, plasma volume and intravascular albumin content decreased and the transcapillary escape rate of albumin increased during...

Raising the Corrosion Resistance of Low-Carbon Steels by Electrolytic-Plasma Saturation with Nitrogen and Carbon

Science.gov (United States)

Kusmanov, S. A.; Grishina, E. P.; Belkin, P. N.; Kusmanova, Yu. V.; Kudryakova, N. O.

2017-05-01

Structural features of the external oxide layer and internal nitrided, carbonitrided and carburized layers in steels 10, 20 and St3 produced by the method of electrolytic plasma treatment are studied. Specimens of the steels are tested for corrosion in a naturally aerated 1-N solution of sodium chloride. The condition of the metal/sodium chloride solution interface is studied by the method of electrochemical impedance spectroscopy. It is shown that the corrosion resistance of low-carbon steels can be raised by anode electrolytic-plasma saturation with nitrogen and carbon. Recommendations are given on the choice of carbonitriding modes for structural steels.

Plasma electrolytic oxide coatings on silumin for oxidation CO

Science.gov (United States)

Borisov, V. A.; Sigaeva, S. S.; Anoshkina, E. A.; Ivanov, A. L.; Litvinov, P. V.; Vedruchenko, V. R.; Temerev, V. L.; Arbuzov, A. B.; Kuznetsov, A. A.; Mukhin, V. A.; Suprunov, G. I.; Chumychko, I. A.; Shlyapin, D. A.; Tsyrul'nikov, P. G.

2017-08-01

Some catalysts of CO oxidation on silumin alloy AK12M2, used for the manufacture of pistons for Russian cars were investigated. The catalysts were prepared by the method of plasma electrolytic oxidation of silumin in electrolytes of various compositions with further activation by the salts Ce, Cu, Co, Ni, Mn and Al. The catalytic tests were carried out in a flow reactor in a mixture of 1% CO and 99% air, with the temperature range of 25-500 °C. The most active catalysts in CO oxidation are those activated with Ce and Cu salts on silumin, treated for 3 hours in an electrolyte containing 4 g/l KOH, 40 g/l Na2B4O7 (conversion of CO is 93.7% at a contact time of 0.25 s). However, the catalysts obtained from silumin treated in the electrolyte containing 3 g/l KOH, 30 g/l Na2SiO3 are more suitable for practical usage. Because when the treatment time of those catalysts is 10 - 20 minutes it is possible to achieve comparable CO conversion. The morphology and composition of the catalysts were studied by the methods of a scanning electron microscope with energy-dispersive surface analysis and X-ray phase analysis. The surface of the non-activated sample consists of γ-Al2O3 and SiO2 particles, due to which the active components get attached to the support. CeO2 and CuO are present on the surface of the sample with the active component.

Permeability and Microstructure of Suspension Plasma-Sprayed YSZ Electrolytes for SOFCs on Various Substrates

Science.gov (United States)

Marr, Michael; Kesler, Olivera

2012-12-01

Yttria-stabilized zirconia electrolyte coatings for solid oxide fuel cells were deposited by suspension plasma spraying using a range of spray conditions and a variety of substrates, including finely structured porous stainless steel disks and cathode layers on stainless steel supports. Electrolyte permeability values and trends were found to be highly dependent on which substrate was used. The most gas-tight electrolyte coatings were those deposited directly on the porous metal disks. With this substrate, permeability was reduced by increasing the torch power and reducing the stand-off distance to produce dense coating microstructures. On the substrates with cathodes, electrolyte permeability was reduced by increasing the stand-off distance, which reduced the formation of segmentation cracks and regions of aligned and concentrated porosity. The formation mechanisms of the various permeability-related coating features are discussed and strategies for reducing permeability are presented. The dependences of electrolyte deposition efficiency and surface roughness on process conditions and substrate properties are also presented.

Hydroxyl radical production in plasma electrolysis with KOH electrolyte solution

Energy Technology Data Exchange (ETDEWEB)

Saksono, Nelson; Febiyanti, Irine Ayu, E-mail: irine.ayu41@ui.ac.id; Utami, Nissa; Ibrahim [Department of Chemical Engineering, Universitas Indonesia, Depok 16424, Indonesia Phone: +62217863516, Fax: +62217863515 (Indonesia)

2015-12-29

Plasma electrolysis is an effective technology for producing hydroxyl radical (•OH). This method can be used for waste degradation process. This study was conducted to obtain the influence of applied voltage, electrolyte concentration, and anode depth in the plasma electrolysis system for producing hydroxyl radical. The materials of anode and cathode, respectively, were made from tungsten and stainless steel. KOH solution was used as the solution. Determination of hydroxyl radical production was done by measuring H{sub 2}O{sub 2} amount formed in plasma system using an iodometric titration method, while the electrical energy consumed was obtained by measuring the electrical current throughout the process. The highest hydroxyl radical production was 3.51 mmol reached with 237 kJ energy consumption in the power supply voltage 600 V, 0.02 M KOH, and 0.5 cm depth of anode.

Apparent molar volumes and compressibilities of selected electrolytes in dimethylsulfoxide

International Nuclear Information System (INIS)

Warminska, Dorota; Grzybkowski, Waclaw

2010-01-01

Densities at T = (293.15, 298.15, 303.15, 313.15, 323.15, and 333.15) K and sound velocities at T = 298.15 K of tetraphenylphosphonium bromide, sodium tetraphenylborate, sodium bromide, and sodium perchlorate in dimethylsulfoxide have been measured over the composition range from (0 to 0.3) mol . kg -1 . From these data, apparent molar volumes and apparent molar isentropic compressibilities at infinite dilution as well as the expansibilities have been evaluated. The results have been discussed in terms of employing tetraphenylphosphonium tetraphenylborate as a reference electrolyte in splitting the limiting apparent molar volumes and apparent molar isentropic compressibilities into ionic contributions.

Solid oxide fuel cell electrolytes produced via very low pressure suspension plasma spray and electrophoretic deposition

Science.gov (United States)

Fleetwood, James D.

Solid oxide fuel cells (SOFCs) are a promising element of comprehensive energy policies due to their direct mechanism for converting the oxidization of fuel, such as hydrogen, into electrical energy. Both very low pressure plasma spray and electrophoretic deposition allow working with high melting temperature SOFC suspension based feedstock on complex surfaces, such as in non-planar SOFC designs. Dense, thin electrolytes of ideal composition for SOFCs can be fabricated with each of these processes, while compositional control is achieved with dissolved dopant compounds that are incorporated into the coating during deposition. In the work reported, sub-micron 8 mole % Y2O3-ZrO2 (YSZ) and gadolinia-doped ceria (GDC), powders, including those in suspension with scandium-nitrate dopants, were deposited on NiO-YSZ anodes, via very low pressure suspension plasma spray (VLPSPS) at Sandia National Laboratories' Thermal Spray Research Laboratory and electrophoretic deposition (EPD) at Purdue University. Plasma spray was carried out in a chamber held at 320 - 1300 Pa, with the plasma composed of argon, hydrogen, and helium. EPD was characterized utilizing constant current deposition at 10 mm electrode separation, with deposits sintered from 1300 -- 1500 °C for 2 hours. The role of suspension constituents in EPD was analyzed based on a parametric study of powder loading, powder specific surface area, polyvinyl butyral (PVB) content, polyethyleneimine (PEI) content, and acetic acid content. Increasing PVB content and reduction of particle specific surface area were found to eliminate the formation of cracks when drying. PEI and acetic acid content were used to control suspension stability and the adhesion of deposits. Additionally, EPD was used to fabricate YSZ/GDC bilayer electrolyte systems. The resultant YSZ electrolytes were 2-27 microns thick and up to 97% dense. Electrolyte performance as part of a SOFC system with screen printed LSCF cathodes was evaluated with peak

A general strategy toward the rational synthesis of metal tungstate nanostructures using plasma electrolytic oxidation method

Energy Technology Data Exchange (ETDEWEB)

Jiang, Yanan; Liu, Baodan, E-mail: baodanliu@imr.ac.cn; Zhai, Zhaofeng; Liu, Xiaoyuan; Yang, Bing; Liu, Lusheng; Jiang, Xin, E-mail: xjiang@imr.ac.cn

2015-11-30

Graphical abstract: A general strategy for the rational synthesis of tungstate nanostructure has been developed based on plasma electrolytic oxidation (PEO) technology (up). Using this method, ZnWO{sub 4} and NiWO{sub 4} nanostructures with controllable morphologies and superior crystallinity can be easily obtained (down), showing obvious advantage in comparison with conventional hydrothermal and sol–gel methods. - Highlights: • Plasma electrolyte oxidation (PEO) method has been used for the rational synthesis of tungstate nanostructures. • ZnWO{sub 4} nanoplates have strong mechanical adhesion with porous TiO{sub 2} film substrate. • The morphology and dimensional size of ZnWO{sub 4} nanostructures can be selectively tailored by controlling the annealing temperature and growth time. • The PEO method can be widely applied to the growth of various metal oxides. - Abstract: A new method based on conventional plasma electrolytic oxidation (PEO) technology has been developed for the rational synthesis of metal tungstate nanostructures. Using this method, ZnWO{sub 4} and NiWO{sub 4} nanostructures with controllable morphologies (nanorods, nanosheets and microsheets) and superior crystallinity have been synthesized. It has been found that the morphology diversity of ZnWO{sub 4} nanostructures can be selectively tailored through tuning the electrolyte concentration and annealing temperatures, showing obvious advantages in comparison to traditional hydrothermal and sol–gel methods. Precise microscopy analyses on the cross section of the PEO coating and ZnWO{sub 4} nanostructures confirmed that the precursors initially precipitated in the PEO coating and its surface during plasma discharge process are responsible for the nucleation and subsequent growth of metal tungstate nanostructures by thermal annealing. The method developed in this work represents a general strategy toward the rational synthesis of metal oxide nanostructures and the formation mechanism of

A general strategy toward the rational synthesis of metal tungstate nanostructures using plasma electrolytic oxidation method

International Nuclear Information System (INIS)

Jiang, Yanan; Liu, Baodan; Zhai, Zhaofeng; Liu, Xiaoyuan; Yang, Bing; Liu, Lusheng; Jiang, Xin

2015-01-01

Graphical abstract: A general strategy for the rational synthesis of tungstate nanostructure has been developed based on plasma electrolytic oxidation (PEO) technology (up). Using this method, ZnWO 4 and NiWO 4 nanostructures with controllable morphologies and superior crystallinity can be easily obtained (down), showing obvious advantage in comparison with conventional hydrothermal and sol–gel methods. - Highlights: • Plasma electrolyte oxidation (PEO) method has been used for the rational synthesis of tungstate nanostructures. • ZnWO 4 nanoplates have strong mechanical adhesion with porous TiO 2 film substrate. • The morphology and dimensional size of ZnWO 4 nanostructures can be selectively tailored by controlling the annealing temperature and growth time. • The PEO method can be widely applied to the growth of various metal oxides. - Abstract: A new method based on conventional plasma electrolytic oxidation (PEO) technology has been developed for the rational synthesis of metal tungstate nanostructures. Using this method, ZnWO 4 and NiWO 4 nanostructures with controllable morphologies (nanorods, nanosheets and microsheets) and superior crystallinity have been synthesized. It has been found that the morphology diversity of ZnWO 4 nanostructures can be selectively tailored through tuning the electrolyte concentration and annealing temperatures, showing obvious advantages in comparison to traditional hydrothermal and sol–gel methods. Precise microscopy analyses on the cross section of the PEO coating and ZnWO 4 nanostructures confirmed that the precursors initially precipitated in the PEO coating and its surface during plasma discharge process are responsible for the nucleation and subsequent growth of metal tungstate nanostructures by thermal annealing. The method developed in this work represents a general strategy toward the rational synthesis of metal oxide nanostructures and the formation mechanism of metal tungstate nanostructures fabricated by

Fabrication of copper-based anodes via atmosphoric plasma spraying techniques

Science.gov (United States)

Lu, Chun [Monroeville, PA

2012-04-24

A fuel electrode anode (18) for a solid oxide fuel cell is made by presenting a solid oxide fuel cell having an electrolyte surface (15), mixing copper powder with solid oxide electrolyte in a mixing step (24, 44) to provide a spray feedstock (30,50) which is fed into a plasma jet (32, 52) of a plasma torch to melt the spray feed stock and propel it onto an electrolyte surface (34, 54) where the spray feed stock flattens into lamellae layer upon solidification, where the layer (38, 59) is an anode coating with greater than 35 vol. % based on solids volume.

Anti-corrosion layer prepared by plasma electrolytic carbonitriding on pure aluminum

International Nuclear Information System (INIS)

Wu, Jie; Zhang, Yifan; Liu, Run; Wang, Bin; Hua, Ming; Xue, Wenbin

2015-01-01

Highlights: • PEC/N can be applied to low melting point metal. • The spectroscopic characterization of plasma discharge is investigated. • Electron concentration and electron temperature are evaluated for PEC/N. • Phase composition of the carbonitrided layer is determined. • PEC/N improves the corrosion resistance of aluminum greatly. - Abstract: In this paper, plasma electrolytic carbonitriding (PEC/N) method was applied to pure aluminum for the first time. The spectroscopic characterization of plasma discharge during PEC/N process was analyzed and the electron temperature was calculated in terms of optical emission spectroscopy. The results showed the discharge plasma was in local thermal equilibrium (LTE) state. Electron concentration and electron temperature were about 6 × 10 21 m −3 and 4000 K, respectively. The carbonitrided layer contained Al 4 C 3 , AlN and Al 7 C 3 N 3 phases. After PEC/N treatment, the corrosion resistance of pure aluminum was significantly improved, which was related to the formation of nitride phases. This work expands the application of plasma electrolysis technology on the surface modification of low melting point metal

Modification of steel surface by plasma electrolytic saturation with nitrogen and carbon

Energy Technology Data Exchange (ETDEWEB)

Kusmanov, S.A., E-mail: sakusmanov@yandex.ru; Kusmanova, Yu.V., E-mail: yulia.kusmanova@yandex.ru; Smirnov, A.A., E-mail: sciencealexsm@gmail.com; Belkin, P.N., E-mail: belkinp@yandex.ru

2016-06-01

The effect of the electrolyte composition with ammonia, acetone, and ammonium chloride on the structure and properties of low carbon steel was studied in anode plasma electrolytic nitrocarburising. An X-ray diffractometer, a scanning electron microscopy (SEM) and an optical microscope were used to characterize the phase composition of the modified layer and its surface morphology. Surface roughness was studied with a profilometer–profilograph. The hardness of the treated and untreated samples was measured using a microhardness tester. The sources of nitrogen and carbon are shown to be the products of evaporation and thermal decomposition of the electrolyte components. It is established that the influence of concentration of ammonia, acetone, and ammonium chloride on the size of the structural components of the hardened layer is explained by the competition of the anode dissolution, high-temperature oxidation and diffusion of the saturating component. The electrolyte composition (10–12.5% ammonium chloride, 5% acetone, 5% ammonia) and processing mode (800 °C, 5–10 min) of low carbon steels allowing to obtain the hardened surface layer up to 0.2 mm with microhardness 930 HV and with decrease in the roughness (R{sub a}) from 1.013 to 0.054 μm are proposed. The anode plasma electrolytic nitricarburising is able to decrease friction coefficient of the treated low carbon steel from 0.191 to 0.169 and wear rate from 13.5 mg to 1.0 mg. - Highlights: • Aqueous solution (12.5% NH{sub 4}Cl, 5% ammonia, 5% acetone) is proposed for PEN/C steels. • Microhardness of steel (0.2% C) is 930 HV due to PEN/C for 5–10 min at 800 °C. • Anode PEN/C of low carbon steel decreases its roughness (R{sub a}) from 1.013 to 0.054 μm. • Anode PEN/C decreases friction coefficient of low carbon steel from 0.191 to 0.169 • Anode PEN/C decreases wear loss of low carbon steel from 13.5 mg to 1.0 mg.

Composite plasma electrolytic oxidation to improve the thermal radiation performance and corrosion resistance on an Al substrate

Energy Technology Data Exchange (ETDEWEB)

Kim, Donghyun [Department of Materials Science and Engineering, Pusan National University, Busan 46241 (Korea, Republic of); Sung, Dahye [Department of Materials Science and Engineering, Pusan National University, Busan 46241 (Korea, Republic of); Korea Institute of Industrial Technology (KITECH), Busan 46742 (Korea, Republic of); Lee, Junghoon [Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Kim, Yonghwan [Korea Institute of Industrial Technology (KITECH), Busan 46742 (Korea, Republic of); Chung, Wonsub, E-mail: wschung1@pusan.ac.kr [Department of Materials Science and Engineering, Pusan National University, Busan 46241 (Korea, Republic of)

2015-12-01

Highlights: • Composite plasma electrolytic oxidation was performed using dispersed CuO particles in convectional PEO electrolyte. • Thermal radiation performance and corrosion resistance were examined by FT-IR spectroscopy and electrochemical methods, respectively. • Deposited copper oxide on the surface of the Al substrate was enhanced the corrosion resistance and the emissivity compared with the conventional PEO. - Abstract: A composite plasma electrolytic oxidation (PEO) was performed for enhancing the thermal radiation performance and corrosion resistance on an Al alloy by dispersing cupric oxide (CuO) particles in a conventional PEO electrolyte. Cu-based oxides (CuO and Cu{sub 2}O) formed by composite PEO increased the emissivity of the substrate to 0.892, and made the surface being dark color, similar to a black body, i.e., an ideal radiator. In addition, the corrosion resistance was analyzed using potentio-dynamic polarization and electrochemical impedance spectroscopy tests in 3.5 wt.% NaCl aqueous solution. An optimum condition of 10 ampere per square decimeter (ASD) current density and 30 min processing time produced appropriate surface morphologies and coating thicknesses, as well as dense Cu- and Al-based oxides that constituted the coating layers.

Gibbs energy calculation of electrolytic plasma channel with inclusions of copper and copper oxide with Al-base

Science.gov (United States)

Posuvailo, V. M.; Klapkiv, M. D.; Student, M. M.; Sirak, Y. Y.; Pokhmurska, H. V.

2017-03-01

The oxide ceramic coating with copper inclusions was synthesized by the method of plasma electrolytic oxidation (PEO). Calculations of the Gibbs energies of reactions between the plasma channel elements with inclusions of copper and copper oxide were carried out. Two methods of forming the oxide-ceramic coatings on aluminum base in electrolytic plasma with copper inclusions were established. The first method - consist in the introduction of copper into the aluminum matrix, the second - copper oxide. During the synthesis of oxide ceramic coatings plasma channel does not react with copper and copper oxide-ceramic included in the coating. In the second case is reduction of copper oxide in interaction with elements of the plasma channel. The content of oxide-ceramic layer was investigated by X-ray and X-ray microelement analysis. The inclusions of copper, CuAl2, Cu9Al4 in the oxide-ceramic coatings were found. It was established that in the spark plasma channels alongside with the oxidation reaction occurs also the reaction aluminothermic reduction of the metal that allows us to dope the oxide-ceramic coating by metal the isobaric-isothermal potential oxidation of which is less negative than the potential of the aluminum oxide.

Anti-corrosion layer prepared by plasma electrolytic carbonitriding on pure aluminum

Energy Technology Data Exchange (ETDEWEB)

Wu, Jie; Zhang, Yifan; Liu, Run; Wang, Bin; Hua, Ming [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Xue, Wenbin, E-mail: xuewb@bnu.edu.cn [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

2015-08-30

Highlights: • PEC/N can be applied to low melting point metal. • The spectroscopic characterization of plasma discharge is investigated. • Electron concentration and electron temperature are evaluated for PEC/N. • Phase composition of the carbonitrided layer is determined. • PEC/N improves the corrosion resistance of aluminum greatly. - Abstract: In this paper, plasma electrolytic carbonitriding (PEC/N) method was applied to pure aluminum for the first time. The spectroscopic characterization of plasma discharge during PEC/N process was analyzed and the electron temperature was calculated in terms of optical emission spectroscopy. The results showed the discharge plasma was in local thermal equilibrium (LTE) state. Electron concentration and electron temperature were about 6 × 10{sup 21} m{sup −3} and 4000 K, respectively. The carbonitrided layer contained Al{sub 4}C{sub 3}, AlN and Al{sub 7}C{sub 3}N{sub 3} phases. After PEC/N treatment, the corrosion resistance of pure aluminum was significantly improved, which was related to the formation of nitride phases. This work expands the application of plasma electrolysis technology on the surface modification of low melting point metal.

Plasma Volume Expansion Resulting from Intravenous Glucose Tolerance Test

Directory of Open Access Journals (Sweden)

Robert G. Hahn

2011-01-01

Full Text Available Objective. To quantify the degree of plasma volume expansion that occurs during an intravenous glucose tolerance test (IVGTT. Methods. Twenty healthy volunteers (mean age, 28 years underwent IVGTTs in which 0.3 g/kg of glucose 30% was injected as a bolus over 1 min. Twelve blood samples were collected over 75 min. The plasma glucose and blood hemoglobin concentrations were used to calculate the volume distribution (Vd and the clearance (CL of both the exogenous glucose and the injected fluid volume. Results. The IVGTT caused a virtually instant plasma volume expansion of 10%. The half-life of the glucose averaged 15 min and the plasma volume expansion 16 min. Correction of the fluid kinetic model for osmotic effects after injection reduced CL for the infused volume by 85%, which illustrates the strength of osmosis in allocating fluid back to the intracellular fluid space. Simulations indicated that plasma volume expansion can be reduced to 60% by increasing the injection time from 1 to 5 min and reducing the glucose load from 0.3 to 0.2 g/kg. Conclusion. A regular IVGTT induced an acute plasma volume expansion that peaked at 10% despite the fact that only 50–80 mL of fluid were administered.

Influence of process parameters on plasma electrolytic surface treatment of tantalum for biomedical applications

Energy Technology Data Exchange (ETDEWEB)

Sowa, Maciej, E-mail: maciej.sowa@polsl.pl [Faculty of Chemistry, Silesian University of Technology, B. Krzywoustego Street 6, 44-100 Gliwice (Poland); Woszczak, Maja; Kazek-Kęsik, Alicja [Faculty of Chemistry, Silesian University of Technology, B. Krzywoustego Street 6, 44-100 Gliwice (Poland); Dercz, Grzegorz [Institute of Materials Science, University of Silesia, 75 Pułku Piechoty Street 1A, 41-500 Chorzów (Poland); Korotin, Danila M. [M.N. Mikheev Institute of Metal Physics of the Ural Branch of Russian Academy of Sciences, S. Kovalevskoi Street 18, 620990 Yekaterinburg (Russian Federation); Institute of Physics and Technology, Ural Federal University, Mira Street 19, 620002 Yekaterinburg (Russian Federation); Zhidkov, Ivan S. [Institute of Physics and Technology, Ural Federal University, Mira Street 19, 620002 Yekaterinburg (Russian Federation); Kurmaev, Ernst Z. [M.N. Mikheev Institute of Metal Physics of the Ural Branch of Russian Academy of Sciences, S. Kovalevskoi Street 18, 620990 Yekaterinburg (Russian Federation); Institute of Physics and Technology, Ural Federal University, Mira Street 19, 620002 Yekaterinburg (Russian Federation); Cholakh, Seif O. [Institute of Physics and Technology, Ural Federal University, Mira Street 19, 620002 Yekaterinburg (Russian Federation); Basiaga, Marcin [Faculty of Biomedical Engineering, Silesian University of Technology, Gen. de Gaulle’a Street 66, 41-800 Zabrze (Poland); Simka, Wojciech, E-mail: wojciech.simka@polsl.pl [Faculty of Chemistry, Silesian University of Technology, B. Krzywoustego Street 6, 44-100 Gliwice (Poland)

2017-06-15

Highlights: • 2-step plasma electrolytic oxidation (PEO) of tantalum was investigated. • PEO coatings surface composition were reflected by the composition of anodizing baths. • Hydrophobic surfaces were obtained from acetate and formate containing baths. • Bioactive phases were identified. - Abstract: This work aims to quantify the effect of anodization voltage and electrolyte composition used during DC plasma electrolytic oxidation (PEO), operated as a 2-step process, on the surface properties of the resulting oxide coatings on tantalum. The first step consisted of galvanostatic anodization (150 mA cm{sup −2}) of the tantalum workpiece up to several limiting voltages (200, 300, 400 and 500 V). After attaining the limiting voltage, the process was switched to voltage control, which resulted in a gradual decrease of the anodic current density. The anodic treatment was realized in a 0.5 M Ca(H{sub 2}PO{sub 2}){sub 2} solution, which was then modified by the addition of 1.15 M Ca(HCOO){sub 2} as well as 1.15 M and 1.5 M Mg(CH{sub 3}COO){sub 2}. The increasing voltage of anodization led to the formation of thicker coatings, with larger pores and enriched with electrolytes species to a higher extent. The solutions containing HCOO{sup −} and CH{sub 3}COO{sup −} ions caused the formation of coatings which were slightly hydrophobic (high contact angle). In the case of the samples anodized up to 500 V, scattered crystalline deposits were observed. Bioactive phases, such as hydroxyapatite, were detected in the treated oxide coatings by XRD and XPS.

Effect of Rehydration Fluid Osmolality on Plasma Volume and Vasopressin in Resting Dehydrated Men

Science.gov (United States)

Geelen, Ghislaine; Greenleaf, J. E.; Keil, L. C.; Wade, Charles E. (Technical Monitor)

1994-01-01

Elevated plasma vasopressin concentration [PVP], which may act as a dipsogen, decreases promptly following the ingestion of fluids in many mammals including humans. The purpose for this study was to determine whether fluids of varied electrolyte and carbohydrate composition and osmolality (Osm] would modify post-drinking decreases in [PVP] which could be attributed to interaction with plasma volume (PV)- or fluid-electrolyte interactive hormones. Five men (23-41 yr, 78.0 +/- SD 8.2 kg), water deprived for 24 h, drank six fluids (12 ml/kg, at 16.5C in 4.0-6.2 min): water (30 m0sm/kg), NaCl (70 mOsm/kg), NaCl + NaCitrate (270 mOsm/kg), NaCl + 9.7% glucose (650 mOsm/kg), and two commercial drinks containing various ionic and carbohydrate contents (380 and 390 mOsm/kg). Blood (20 ml/sample) was drawn at -5 min before and at +3, +9, +15, +30, and +70 min after drinking. Heart rate, blood pressures, and plasma renin activity, {Na+], [K+], [Osm], aldosterone, atrial natriuretic peptide, and epinephrine concentrations were unchanged after drinking. Post-drinking [PVP] decreased from 1.7 - 3.7 pg/ml within 3 min with all fluids independently of their composition, [Osm], or delta PV; with maximal depression to 0.1-0.7 pg/ml (p<0.05) by 15 min. The continued [PVP] depression with all fluids from 15 to 70 min was accompanied by unchanged plasma (Osm] but 1.8-7.6% increases (p<0.05) in PV with 3) fluids (2 commercial and NaCitrate) and no change with the others. Percent changes in mean [PVP] and plasma norepinephrine concentrations [PNE] at 15 min correlated -0.70 (P<0.10) suggesting that about half the variability in [PVP I I depression was associated with [PNE]. Thus, part of the mechanism for post-drinking [PVP] depression may involve a drinking stimulated norepinephrine (neural) factor.

Data on the surface morphology of additively manufactured Ti-6Al-4V implants during processing by plasma electrolytic oxidation

Directory of Open Access Journals (Sweden)

Ingmar A.J. van Hengel

2017-08-01

Full Text Available Additively manufactured Ti-6Al-4V implants were biofunctionalized using plasma electrolytic oxidation. At various time points during this process scanning electron microscopy imaging was performed to analyze the surface morphology (van Hengel et al., 2017 [1]. This data shows the changes in surface morphology during plasma electrolytic oxidation. Data presented in this article are related to the research article “Selective laser melting porous metallic implants with immobilized silver nanoparticles kill and prevent biofilm formation by methicillin-resistant Staphylococcus aureus” (van Hengel et al., 2017 [1].

Enhanced mechanical properties and increased corrosion resistance of a biodegradable magnesium alloy by plasma electrolytic oxidation (PEO).

Science.gov (United States)

White, Leon; Koo, Youngmi; Neralla, Sudheer; Sankar, Jagannathan; Yun, Yeoheung

2016-06-01

We report the enhanced mechanical properties of AZ31 magnesium alloys by plasma electrolytic oxidation (PEO) coating in NaOH, Na 2 SiO 3 , KF and NaH 2 PO 4 ·2H 2 O containing electrolytes. Mechanical properties including wear resistance, surface hardness and elastic modulus were increased for PEO-coated AZ31 Mg alloys (PEO-AZ31). DC polarization in Hank's solution indicating that the corrosion resistance significantly increased for PEO-coating in KF-contained electrolyte. Based on these results, the PEO coating method shows promising potential for use in biodegradable implant applications where tunable corrosion and mechanical properties are needed.

Low Plasma Volume in Normotensive Formerly Preeclamptic Women Predisposes to Hypertension.

Science.gov (United States)

Scholten, Ralph R; Lotgering, Fred K; Hopman, Maria T; Van Dijk, Arie; Van de Vlugt, Maureen; Janssen, Mirian C H; Spaanderman, Marc E A

2015-11-01

Formerly preeclamptic women are at risk for cardiovascular disease. Low plasma volume may reflect latent hypertension and potentially links preeclampsia with chronic cardiovascular disease. We hypothesized that low plasma volume in normotensive formerly preeclamptic women predisposes to hypertension. We longitudinally studied n=104 formerly preeclamptic women in whom plasma volume was measured 3 to 30 months after the preeclamptic pregnancy. Cardiovascular variables were assessed at 2 points in time (3-30 months postpartum and 2-5 years thereafter). Study population was divided into low plasma volume (≤1373 mL/m(2)) and normal plasma volume (>1373 mL/m(2)). Primary end point was hypertension at the second visit: defined as ≥140 mm Hg systolic or ≥90 mm Hg diastolic. Secondary outcome of this study was change in traditional cardiovascular risk profile between visits. Variables correlating univariately with change in blood pressure between visits were introduced in regression analysis. Eighteen of 104 (17%) formerly preeclamptic women who were normotensive at first visit had hypertension at second evaluation 2 to 5 years later. Hypertension developed more often in women with low plasma volume (10/35 [29%]) than in women with normal plasma volume (8/69 [12%]; odds ratio, 3.2; 95% confidence interval, 1.4-8.6). After adjustments, relationship between plasma volume status and subsequent hypertension persisted (adjusted odds ratio, 3.0; 95% confidence interval, 1.1-8.5). Mean arterial pressure at second visit correlated inverse linearly with plasma volume (r=-0.49; Phypertension within 5 years. Women with low plasma volume have higher chance to develop hypertension than women with normal plasma volume. Clinically, follow-up of blood pressure seems warranted in women with history of preeclampsia, even when initially normotensive. © 2015 American Heart Association, Inc.

Capacity Decay Mitigation by Asymmetric Positive/Negative Electrolyte Volumes in Vanadium Redox Flow Batteries.

Science.gov (United States)

Park, Jong Ho; Park, Jung Jin; Park, O Ok; Yang, Jung Hoon

2016-11-23

Capacity decay in vanadium redox flow batteries during charge-discharge cycling has become an important issue because it lowers the practical energy density of the battery. The battery capacity tends to drop rapidly within the first tens of cycles and then drops more gradually over subsequent cycles during long-term operation. This paper analyzes and discusses the reasons for this early capacity decay. The imbalanced crossover rate of vanadium species was found to remain high until the total difference in vanadium concentration between the positive and negative electrolytes reached almost 1 mol dm -3 . To minimize the initial crossover imbalance, we introduced an asymmetric volume ratio between the positive and negative electrolytes during cell operation. Changing this ratio significantly reduced the capacity fading rate of the battery during the early cycles and improved its capacity retention at steady state. As an example, the practical energy density of the battery increased from 15.5 to 25.2 Wh L -1 simply after reduction of the positive volume by 25 %. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Human Water and Electrolyte Balance

National Research Council Canada - National Science Library

Montain, S. J; Cheuvront, S. N; Carter, R; Sawka, M. N

2006-01-01

.... Sweat losses, if not replaced, reduce body water volume and electrolyte content. Excessive body water or electrolyte losses can disrupt physiological homeostasis and threaten both health and performance...

Application of sol gel spin coated yttria-stabilized zirconia layers for the improvement of solid oxide fuel cell electrolytes produced by atmospheric plasma spraying

Energy Technology Data Exchange (ETDEWEB)

Rose, Lars [University of British Columbia, Department of Materials Engineering, 309-6350 Stores Road, Vancouver, British Columbia, V6T 1Z4 (Canada); National Research Council, Institute for Fuel Cell Innovation, 4250 Wesbrook Mall, Vancouver, British Columbia, V6T 1W5 (Canada); Kesler, Olivera [National Research Council, Institute for Fuel Cell Innovation, 4250 Wesbrook Mall, Vancouver, British Columbia, V6T 1W5 (Canada); University of British Columbia, Department of Mechanical Engineering, 2054-6250 Applied Science Lane, Vancouver, British Columbia, V6T 1Z4 (Canada); Tang, Zhaolin; Burgess, Alan [Northwest Mettech Corp., 467 Mountain Hwy, North Vancouver, British Columbia, V7J 2L3 (Canada)

2007-05-15

Due to its high thermal stability and purely oxide ionic conductivity, yttria-stabilized zirconia (YSZ) is the most commonly used electrolyte material for solid oxide fuel cells (SOFCs). Standard electrolyte fabrication techniques for planar SOFCs involve wet ceramic techniques such as tape-casting or screen printing, requiring sintering steps at temperatures above 1300 C. Plasma spraying (PS) may provide a more rapid and cost efficient method to produce SOFCs without sintering. High-temperature sintering requires long processing times and can lead to oxidation of metal alloys used as mechanical supports, or to detrimental interreactions between the electrolyte and adjacent electrode layers. This study investigates the use of spin coated sol gel derived YSZ precursor solutions to fill the pores present in plasma sprayed YSZ layers, and to enhance the surface area for reaction at the electrolyte-cathode interface, without the use of high-temperature firing steps. The effects of different plasma conditions and sol concentrations and solid loadings on the gas permeability and fuel cell performance have been investigated. (author)

The volume-expanding effects of autologous liquid stored plasma following hemorrhage

DEFF Research Database (Denmark)

Bentzer, Peter; Thomas, Owain D; Westborg, Johan

2012-01-01

of plasma transfusion on plasma volume. We report a prospective interventional study in which the plasma volume-expanding effect of autologous plasma was investigated after a controlled hemorrhage. Methods. Plasma obtained by plasmapheresis from nine healthy regular blood donors was stored at 2-6°C. Five...

Zirconia based ceramic coating on a metal with plasma electrolytic oxidation

Science.gov (United States)

Akatsu, T.; Kato, T.; Shinoda, Y.; Wakai, F.

2011-10-01

We challenge to fabricate a thermal barrier coating (TBC) made of ZrO2 based ceramics on a Ni based single crystal superalloy with plasma electrolytic oxidation (PEO) by incorporating metal species from electrolyte into the coating. The PEO process is carried out on the superalloy galvanized with aluminium for 15min in Na4O7P4 solution for an oxygen barrier coating (OBC) and is followed by PEO in K2[Zr(CO3)2(OH)2] solution for TBC. We obtained the following results; (1) Monoclinic-, tetragonal-, cubic-ZrO2 crystals were detected in TBC. (2) High porosity with large pores was observed near the interface between OBC and TBC. The fine grain structure with a grain size of about 300nm was typically observed. (3) The adhesion strength between PEO coatings and substrate was evaluated to be 26.8±6.6MPa. At the adhesion strength test, PEO coatings fractured around the interface between OBC and TBC. The effect of coating structure on adhesion strength is explained through the change in spark discharge during PEO process.

Using Electrolyte Free Water Balance to Rationalize and Treat Dysnatremias.

Science.gov (United States)

Shah, Sanjeev R; Bhave, Gautam

2018-01-01

Dysnatremias or abnormalities in plasma [Na + ] are often termed disorders of water balance, an unclear physiologic concept often confused with changes in total fluid balance. However, most clinicians clearly recognize that hypertonic or hypotonic gains or losses alter plasma [Na + ], while isotonic changes do not modify plasma [Na + ]. This concept can be conceptualized as the electrolyte free water balance (EFWB), which defines the non-isotonic components of inputs and outputs to determine their effect on plasma [Na + ]. EFWB is mathematically proportional to the rate of change in plasma [Na + ] (dP Na /dt) and, therefore, is actively regulated to zero so that plasma [Na + ] remains stable at its homeostatic set point. Dysnatremias are, therefore, disorders of EFWB and the relationship between EFWB and dP Na /dt provides a rationale for therapeutic strategies incorporating mass and volume balance. Herein, we leverage dP Na /dt as a desired rate of correction of plasma [Na + ] to define a stepwise approach for the treatment of dysnatremias.

Using Electrolyte Free Water Balance to Rationalize and Treat Dysnatremias

Science.gov (United States)

Shah, Sanjeev R.; Bhave, Gautam

2018-01-01

Dysnatremias or abnormalities in plasma [Na+] are often termed disorders of water balance, an unclear physiologic concept often confused with changes in total fluid balance. However, most clinicians clearly recognize that hypertonic or hypotonic gains or losses alter plasma [Na+], while isotonic changes do not modify plasma [Na+]. This concept can be conceptualized as the electrolyte free water balance (EFWB), which defines the non-isotonic components of inputs and outputs to determine their effect on plasma [Na+]. EFWB is mathematically proportional to the rate of change in plasma [Na+] (dPNa/dt) and, therefore, is actively regulated to zero so that plasma [Na+] remains stable at its homeostatic set point. Dysnatremias are, therefore, disorders of EFWB and the relationship between EFWB and dPNa/dt provides a rationale for therapeutic strategies incorporating mass and volume balance. Herein, we leverage dPNa/dt as a desired rate of correction of plasma [Na+] to define a stepwise approach for the treatment of dysnatremias. PMID:29740578

Using Electrolyte Free Water Balance to Rationalize and Treat Dysnatremias

Directory of Open Access Journals (Sweden)

Sanjeev R. Shah

2018-04-01

Full Text Available Dysnatremias or abnormalities in plasma [Na+] are often termed disorders of water balance, an unclear physiologic concept often confused with changes in total fluid balance. However, most clinicians clearly recognize that hypertonic or hypotonic gains or losses alter plasma [Na+], while isotonic changes do not modify plasma [Na+]. This concept can be conceptualized as the electrolyte free water balance (EFWB, which defines the non-isotonic components of inputs and outputs to determine their effect on plasma [Na+]. EFWB is mathematically proportional to the rate of change in plasma [Na+] (dPNa/dt and, therefore, is actively regulated to zero so that plasma [Na+] remains stable at its homeostatic set point. Dysnatremias are, therefore, disorders of EFWB and the relationship between EFWB and dPNa/dt provides a rationale for therapeutic strategies incorporating mass and volume balance. Herein, we leverage dPNa/dt as a desired rate of correction of plasma [Na+] to define a stepwise approach for the treatment of dysnatremias.

Increasing Wear Resistance of Titanium Alloys by Anode Plasma Electrolytic Saturation with Interstitial Elements

Science.gov (United States)

Belkin, P. N.; Kusmanov, S. A.; Dyakov, I. G.; Silkin, S. A.; Smirnov, A. A.

2017-05-01

In our previous studies, we have shown that anode plasma electrolytic saturation of titanium alloys with nitrogen and carbon can improve their tribological properties. Obtained structure containing oxide layer and solid solution of diffused element in titanium promotes the enhancement of running-in ability and the decrease in the wear rate in some special cases. In this paper, further investigations are reported regarding the tribological properties of alpha- and beta-titanium alloys in wear test against hardened steel (50 HRC) disk using pin-on-disk geometry and balls of Al2O3 (6.25 mm in diameter) or bearing steel (9.6 mm in diameter) with ball-on-plate one and normal load from 5 to 209 N. Reproducible results were obtained under testing samples treated by means of the plasma electrolytic nitriding (PEN) with the mechanical removal of the oxide layer. Friction coefficient of nitrided samples is 0.5-0.9 which is somewhat higher than that for untreated one (0.48-0.75) during dry sliding against Al2O3 ball. An increase in the sliding speed results in the polishing of nitrided samples and reduction of their wear rate by 60 times. This result is obtained for 5 min at 850 °C using PEN in electrolyte containing 5 wt.% ammonia and 10 wt.% ammonium chloride followed by quenching in solution. Optical microscope was employed to assist in the evaluation of the wear behavior. Sizes of wear tracks were measured by profilometer TR200.

blood and plasma volumes in normal west african dwarf sheep

African Journals Online (AJOL)

Dr Olaleye

volume (PCV) and haemoglobin (Hb) values were determined as descried by Benjamin (1978) using the microhaematocrit and ... Standard dye concentration of 20 mg/ml was used for determining the dye concentration in plasma. ... Haemoglobin (Hb), Plasma Volume and Blood Volume in the West African Dwarf. Sheep.

Effect of large volume paracentesis on plasma volume--a cause of hypovolemia

International Nuclear Information System (INIS)

Kao, H.W.; Rakov, N.E.; Savage, E.; Reynolds, T.B.

1985-01-01

Large volume paracentesis, while effectively relieving symptoms in patients with tense ascites, has been generally avoided due to reports of complications attributed to an acute reduction in intravascular volume. Measurements of plasma volume in these subjects have been by indirect methods and have not uniformly confirmed hypovolemia. We have prospectively evaluated 18 patients (20 paracenteses) with tense ascites and peripheral edema due to chronic liver disease undergoing 5 liter paracentesis for relief of symptoms. Plasma volume pre- and postparacentesis was assessed by a 125 I-labeled human serum albumin dilution technique as well as by the change in hematocrit and postural blood pressure difference. No significant change in serum sodium, urea nitrogen, hematocrit or postural systolic blood pressure difference was noted at 24 or 48 hr after paracentesis. Serum creatinine at 24 hr after paracentesis was unchanged but a small but statistically significant increase in serum creatinine was noted at 48 hr postparacentesis. Plasma volume changed -2.7% (n = 6, not statistically significant) during the first 24 hr and -2.8% (n = 12, not statistically significant) during the 0- to 48-hr period. No complications from paracentesis were noted. These results suggest that 5 liter paracentesis for relief of symptoms is safe in patients with tense ascites and peripheral edema from chronic liver disease

Plasma electrolytic oxidation treatment mode influence on corrosion properties of coatings obtained on Zr-1Nb alloy in silicate-phosphate electrolyte

Science.gov (United States)

Farrakhov, R. G.; Mukaeva, V. R.; Fatkullin, A. R.; Gorbatkov, M. V.; Tarasov, P. V.; Lazarev, D. M.; Babu, N. Ramesh; Parfenov, E. V.

2018-01-01

This research is aimed at improvement of corrosion properties for Zr-1Nb alloy via plasma electrolytic oxidation (PEO). The coatings obtained in DC, pulsed unipolar and pulsed bipolar modes were assessed using SEM, XRD, PDP and EIS techniques. It was shown that pulsed unipolar mode provides the PEO coatings having promising combination of the coating thickness, surface roughness, porosity, corrosion potential and current density, and charge transfer resistance, all contributing to corrosion protection of the zirconium alloy for advanced fuel cladding applications.

Properties of nanostructured undoped ZrO{sub 2} thin film electrolytes by plasma enhanced atomic layer deposition for thin film solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Cho, Gu Young; Noh, Seungtak; Lee, Yoon Ho; Cha, Suk Won, E-mail: ybkim@hanyang.ac.kr, E-mail: swcha@snu.ac.kr [Department of Mechanical and Aerospace Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Ji, Sanghoon [Graduate School of Convergence Science and Technology, Seoul National University, Iui-dong, Yeongtong-gu, Suwon 443-270 (Korea, Republic of); Hong, Soon Wook; Koo, Bongjun; Kim, Young-Beom, E-mail: ybkim@hanyang.ac.kr, E-mail: swcha@snu.ac.kr [Department of Mechanical Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791 (Korea, Republic of); An, Jihwan [Manufacturing Systems and Design Engineering Programme, Seoul National University of Science and Technology, 232 Gongneung-ro, Nowon-gu, Seoul 139-743 (Korea, Republic of)

2016-01-15

Nanostructured ZrO{sub 2} thin films were prepared by thermal atomic layer deposition (ALD) and by plasma-enhanced atomic layer deposition (PEALD). The effects of the deposition conditions of temperature, reactant, plasma power, and duration upon the physical and chemical properties of ZrO{sub 2} films were investigated. The ZrO{sub 2} films by PEALD were polycrystalline and had low contamination, rough surfaces, and relatively large grains. Increasing the plasma power and duration led to a clear polycrystalline structure with relatively large grains due to the additional energy imparted by the plasma. After characterization, the films were incorporated as electrolytes in thin film solid oxide fuel cells, and the performance was measured at 500 °C. Despite similar structure and cathode morphology of the cells studied, the thin film solid oxide fuel cell with the ZrO{sub 2} thin film electrolyte by the thermal ALD at 250 °C exhibited the highest power density (38 mW/cm{sup 2}) because of the lowest average grain size at cathode/electrolyte interface.

Plasma Membranes Modified by Plasma Treatment or Deposition as Solid Electrolytes for Potential Application in Solid Alkaline Fuel Cells

Science.gov (United States)

Reinholdt, Marc; Ilie, Alina; Roualdès, Stéphanie; Frugier, Jérémy; Schieda, Mauricio; Coutanceau, Christophe; Martemianov, Serguei; Flaud, Valérie; Beche, Eric; Durand, Jean

2012-01-01

In the highly competitive market of fuel cells, solid alkaline fuel cells using liquid fuel (such as cheap, non-toxic and non-valorized glycerol) and not requiring noble metal as catalyst seem quite promising. One of the main hurdles for emergence of such a technology is the development of a hydroxide-conducting membrane characterized by both high conductivity and low fuel permeability. Plasma treatments can enable to positively tune the main fuel cell membrane requirements. In this work, commercial ADP-Morgane® fluorinated polymer membranes and a new brand of cross-linked poly(aryl-ether) polymer membranes, named AMELI-32®, both containing quaternary ammonium functionalities, have been modified by argon plasma treatment or triallylamine-based plasma deposit. Under the concomitant etching/cross-linking/oxidation effects inherent to the plasma modification, transport properties (ionic exchange capacity, water uptake, ionic conductivity and fuel retention) of membranes have been improved. Consequently, using plasma modified ADP-Morgane® membrane as electrolyte in a solid alkaline fuel cell operating with glycerol as fuel has allowed increasing the maximum power density by a factor 3 when compared to the untreated membrane. PMID:24958295

Plasma membranes modified by plasma treatment or deposition as solid electrolytes for potential application in solid alkaline fuel cells.

Science.gov (United States)

Reinholdt, Marc; Ilie, Alina; Roualdès, Stéphanie; Frugier, Jérémy; Schieda, Mauricio; Coutanceau, Christophe; Martemianov, Serguei; Flaud, Valérie; Beche, Eric; Durand, Jean

2012-07-30

In the highly competitive market of fuel cells, solid alkaline fuel cells using liquid fuel (such as cheap, non-toxic and non-valorized glycerol) and not requiring noble metal as catalyst seem quite promising. One of the main hurdles for emergence of such a technology is the development of a hydroxide-conducting membrane characterized by both high conductivity and low fuel permeability. Plasma treatments can enable to positively tune the main fuel cell membrane requirements. In this work, commercial ADP-Morgane® fluorinated polymer membranes and a new brand of cross-linked poly(aryl-ether) polymer membranes, named AMELI-32®, both containing quaternary ammonium functionalities, have been modified by argon plasma treatment or triallylamine-based plasma deposit. Under the concomitant etching/cross-linking/oxidation effects inherent to the plasma modification, transport properties (ionic exchange capacity, water uptake, ionic conductivity and fuel retention) of membranes have been improved. Consequently, using plasma modified ADP-Morgane® membrane as electrolyte in a solid alkaline fuel cell operating with glycerol as fuel has allowed increasing the maximum power density by a factor 3 when compared to the untreated membrane.

Plasma electrolytic oxidation of magnesium and its alloys: Mechanism, properties and applications

Directory of Open Access Journals (Sweden)

Gh. Barati Darband

2017-03-01

Full Text Available Plasma Electrolyte Oxidation (PEO process has increasingly been employed to improve magnesium surface properties by fabrication of an MgO-based coating. Originating from conventional anodizing procedures, this high-voltage process produces an adhesive ceramic film on the surface. The present article provides a comprehensive review around mechanisms of PEO coatings fabrication and their different properties. Due to complexity of PEO coatings formation, a complete explanation regarding fabrication mechanisms of PEO coatings has not yet been proposed; however, the most important advancements in the field of fabrication mechanisms of PEO coatings were gathered in this work. Mechanisms of PEO coatings fabrication on magnesium were reviewed considering voltage–time plots, optical spectrometry, acoustic emission spectrometry and electronic properties of the ceramic film. Afterwards, the coatings properties, affecting parameters and improvement strategies were discussed. In addition, corrosion resistance of coatings, important factors in corrosion resistance and methods for corrosion resistance improvement were considered. Tribological properties (important factors and improvement methods of coatings were also studied. Since magnesium and its alloys are broadly used in biological applications, the biological properties of PEO coatings, important factors in their biological performance and existing methods for improvement of coatings were explained. Addition of ceramic based nanoparticles and formation of nanocomposite coatings may considerably influence properties of plasma electrolyte oxidation coatings. Nanocomposite coatings properties and nanoparticles adsorption mechanisms were included in a separate sector. Another method to improve coatings properties is formation of hybrid coatings on PEO coatings which was discussed in the end.

Plasma volume in acute hypoxia

DEFF Research Database (Denmark)

Poulsen, T D; Klausen, T; Richalet, J P

1998-01-01

Exposure to acute hypoxia is associated with changes in body fluid homeostasis and plasma volume (PV). This study compared a dye dilution technique using Evans' blue (PV[Evans']) with a carbon monoxide (CO) rebreathing method (PV[CO]) for measurements of PV in ten normal subjects at sea level...

Method of electrolytically decontaminating of radioactive metal wastes

International Nuclear Information System (INIS)

Oonuma, Tsutomu; Tanaka, Akio; Yamadera, Toshio.

1985-01-01

Purpose: To significantly reduce the volume of secondary wastes by separating from electrolytes metal ions containing radioactive metal ions dissolved therein in the form of elemental metals of a reduced volume with ease, as well as regenerating the electrolytes for re-use. Method: Contaminated portions at the surface of the radioactive metal wastes are dissolved in electrolytes and, when the metal ion concentration in the electrolytes reaches a predetermined level, the electrolytes are introduced to an acid recovery step and an electrodeposition step. The recovered acid is re-used as the electrolytes, while dissolved metal ions containing radioactive metal ions are deposited as elemental metals in the electrodeposition step. The electrolytes usable herein include those acids easily forming stable complex compounds with the metals or those not forming hydroxides of the contaminated metals. Combination of sodium sulfate and sulfuric acid, sodium chloride and hydrochloride or the like is preferred. (Kamimura, M.)

Corrosion evaluation of zirconium doped oxide coatings on aluminum formed by plasma electrolytic oxidation.

Science.gov (United States)

Bajat, Jelena; Mišković-Stanković, Vesna; Vasilić, Rastko; Stojadinović, Stevan

2014-01-01

The plasma electrolytic oxidation (PEO) of aluminum in sodium tungstate (Na(2)WO(4) · (2)H(2)O) and Na(2)WO(4) · (2)H(2)O doped with Zr was analyzed in order to obtain oxide coatings with improved corrosion resistance. The influence of current density in PEO process and anodization time was investigated, as well as the influence of Zr, with the aim to find out how they affect the chemical content, morphology, surface roughness, and corrosion stability of oxide coatings. It was shown that the presence of Zr increases the corrosion stability of oxide coatings for all investigated PEO times. Evolution of EIS spectra during the exposure to 3% NaCl, as a strong corrosive agent, indicated the highest corrosion stability for PEO coating formed on aluminum at 70 mA/cm(2) for 2 min in a zirconium containing electrolyte.

Influence of the reuse of the electrolytic solution on the properties of hydroxyapatite coatings produced by plasma electrolytic oxidation of grade 4 titanium

Energy Technology Data Exchange (ETDEWEB)

Antonio, Cesar A.; Rangel, Elidiane Cipriano; Cruz, Nilson Cristino, E-mail: cesar.augustoa@hotmail.com [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Sorocaba, SP (Brazil)

2016-07-01

Full text: Plasma electrolytic oxidation (PEO) is a process able to produce oxide coatings on light metals, such as Al, Ti, V, Mg, Ta and Nb. In this technique, the application of a voltage, in the range of hundreds of volts, between the sample and a cathode immersed in an electrolyte solution produces electrical fields intense enough to breakdown the insulating oxide layer on the sample surface giving rise to micro electric sparks[1]. These micro-arcs can locally melt the substrate alloying it with elements in the electrolyte solution [2]. In this work PEO has been used to produce coatings with high concentration of hydroxyapatite on Grade 4 titanium disks. The treatments were performed in a 1 liter stainless steel tank. The tank wall was used as the cathode and the coatings were produced during 120 s using calcium acetate and sodium glycerophosphate water solutions as electrolyte. The samples were biased with 480 V pulses with frequency and duty cycle of 100 Hz and 60%, respectively. Using profilometry, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction it has been evaluated the influence of the number of reuses of the solution on the coating properties. The coating produced contains around 85% of HA and it has not been observed any significant changes in their properties when the same solution was reused up to 5 times. [1] A.L. Yerokhin, X. Nie, A. Leyland, A. Matthews, Surf. Coat. Technol. 130 (2000) 195 206. [2] C. A. Antonio, N. C. Cruz, et al. Materials Research. 17(6) 2014; 1427-1433. (author)

X-ray Computed Tomographic Investigation of the Porosity and Morphology of Plasma Electrolytic Oxidation Coatings

Czech Academy of Sciences Publication Activity Database

Zhang, X.; Aliasghari, S.; Němcová, A.; Burnett, T.L.; Kuběna, Ivo; Šmíd, Miroslav; Thompson, G.; Skeldon, P.; Withers, P.J.

2016-01-01

Roč. 8, č. 13 (2016), s. 8801-8810 ISSN 1944-8244 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : plasma electrolytic oxidation * porosity * scanning electron microscopy * titanium * X-ray computed tomography Subject RIV: JK - Corrosion ; Surface Treatment of Materials Impact factor: 7.504, year: 2016 http://pubs.acs.org/doi/abs/10.1021/acsami.6b00274

Tribological and Corrosion Properties of Coatings Produced by Plasma Electrolytic Oxidation on the ZA27 Alloy

Science.gov (United States)

Li, Guangyin; Mao, Yifan; Li, Zhijian; Wang, Linlin; DaCosta, Herbert

2018-05-01

In this paper, a continuous and dense coating was deposited on samples of the ZA27 alloy through the plasma electrolytic oxidation (PEO) process to improve its wear and corrosion performance. A nontoxic and environmentally friendly inorganic salt, Na2SiO3, is chosen as electrolytes with different concentrations. The effect of the concentration of Na2SiO3 aqueous solutions on the coating performances was investigated. The coatings with 3Al2O3·2SiO2 (mullite), Zn2SiO4 and Al2O3 (either crystal phase or with some amorphous SiO2 phases) were formed by the PEO processes. It was found that the coating thickness increased with the increase in electrolyte concentration. However, the wear and corrosion resistance performance of the coatings did not improve as the coating's thickness increased. This was due to the fact that the coating produced with electrolytes of 10 g/L has a porous structure with large pore size. Among all the samples, coating produced by 15 g/L Na2SiO3 has the best wear and corrosion resistance, which is attributed to its continuous and dense structure with thickness of about 47 μm.

Tribological and Corrosion Properties of Coatings Produced by Plasma Electrolytic Oxidation on the ZA27 Alloy

Science.gov (United States)

Li, Guangyin; Mao, Yifan; Li, Zhijian; Wang, Linlin; DaCosta, Herbert

2018-04-01

In this paper, a continuous and dense coating was deposited on samples of the ZA27 alloy through the plasma electrolytic oxidation (PEO) process to improve its wear and corrosion performance. A nontoxic and environmentally friendly inorganic salt, Na2SiO3, is chosen as electrolytes with different concentrations. The effect of the concentration of Na2SiO3 aqueous solutions on the coating performances was investigated. The coatings with 3Al2O3·2SiO2 (mullite), Zn2SiO4 and Al2O3 (either crystal phase or with some amorphous SiO2 phases) were formed by the PEO processes. It was found that the coating thickness increased with the increase in electrolyte concentration. However, the wear and corrosion resistance performance of the coatings did not improve as the coating's thickness increased. This was due to the fact that the coating produced with electrolytes of 10 g/L has a porous structure with large pore size. Among all the samples, coating produced by 15 g/L Na2SiO3 has the best wear and corrosion resistance, which is attributed to its continuous and dense structure with thickness of about 47 μm.

Coupling of RF antennas to large volume helicon plasma

Directory of Open Access Journals (Sweden)

Lei Chang

2018-04-01

Full Text Available Large volume helicon plasma sources are of particular interest for large scale semiconductor processing, high power plasma propulsion and recently plasma-material interaction under fusion conditions. This work is devoted to studying the coupling of four typical RF antennas to helicon plasma with infinite length and diameter of 0.5 m, and exploring its frequency dependence in the range of 13.56-70 MHz for coupling optimization. It is found that loop antenna is more efficient than half helix, Boswell and Nagoya III antennas for power absorption; radially parabolic density profile overwhelms Gaussian density profile in terms of antenna coupling for low-density plasma, but the superiority reverses for high-density plasma. Increasing the driving frequency results in power absorption more near plasma edge, but the overall power absorption increases with frequency. Perpendicular stream plots of wave magnetic field, wave electric field and perturbed current are also presented. This work can serve as an important reference for the experimental design of large volume helicon plasma source with high RF power.

Capillary plasma jet: A low volume plasma source for life science applications

Energy Technology Data Exchange (ETDEWEB)

Topala, I., E-mail: ionut.topala@uaic.ro, E-mail: tmnagat@ipc.shizuoka.ac.jp [Alexandru Ioan Cuza University of Iasi, Faculty of Physics, Iasi Plasma Advanced Research Center (IPARC), Bd. Carol I No. 11, Iasi 700506 (Romania); Nagatsu, M., E-mail: ionut.topala@uaic.ro, E-mail: tmnagat@ipc.shizuoka.ac.jp [Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561 (Japan)

2015-02-02

In this letter, we present results from multispectroscopic analysis of protein films, after exposure to a peculiar plasma source, i.e., the capillary plasma jet. This plasma source is able to generate very small pulsed plasma volumes, in kilohertz range, with characteristic dimensions smaller than 1 mm. This leads to specific microscale generation and transport of all plasma species. Plasma diagnosis was realized using general electrical and optical methods. Depending on power level and exposure duration, this miniature plasma jet can induce controllable modifications to soft matter targets. Detailed discussions on protein film oxidation and chemical etching are supported by results from absorption, X-ray photoelectron spectroscopy, and microscopy techniques. Further exploitation of principles presented here may consolidate research interests involving plasmas in biotechnologies and plasma medicine, especially in patterning technologies, modified biomolecule arrays, and local chemical functionalization.

Capillary plasma jet: A low volume plasma source for life science applications

Science.gov (United States)

Topala, I.; Nagatsu, M.

2015-02-01

In this letter, we present results from multispectroscopic analysis of protein films, after exposure to a peculiar plasma source, i.e., the capillary plasma jet. This plasma source is able to generate very small pulsed plasma volumes, in kilohertz range, with characteristic dimensions smaller than 1 mm. This leads to specific microscale generation and transport of all plasma species. Plasma diagnosis was realized using general electrical and optical methods. Depending on power level and exposure duration, this miniature plasma jet can induce controllable modifications to soft matter targets. Detailed discussions on protein film oxidation and chemical etching are supported by results from absorption, X-ray photoelectron spectroscopy, and microscopy techniques. Further exploitation of principles presented here may consolidate research interests involving plasmas in biotechnologies and plasma medicine, especially in patterning technologies, modified biomolecule arrays, and local chemical functionalization.

Transmission electron microscopy of coatings formed by plasma electrolytic oxidation of titanium.

Science.gov (United States)

Matykina, E; Arrabal, R; Skeldon, P; Thompson, G E

2009-05-01

Transmission electron microscopy and supporting film analyses are used to investigate the changes in composition, morphology and structure of coatings formed on titanium during DC plasma electrolytic oxidation in a calcium- and phosphorus-containing electrolyte. The coatings are of potential interest as bioactive surfaces. The initial barrier film, of mixed amorphous and nanocrystalline structure, formed below the sparking voltage of 180 V, incorporates small amounts of phosphorus and calcium species, with phosphorus confined to the outer approximately 63% of the coating thickness. On commencement of sparking, calcium- and phosphorus-rich amorphous material forms at the coating surface, with local heating promoting crystallization in underlying and adjacent anodic titania. The amorphous material thickens with increased treatment time, comprising almost the whole of the approximately 5.7-microm-thick coating formed at 340 V. At this stage, the coating is approximately 4.4 times thicker than the oxidized titanium, with a near-surface composition of about 12 at.% Ti, 58 at.% O, 19 at.% P and 11 at.% Ca. Further, the amount of titanium consumed in forming the coating is similar to that calculated from the anodizing charge, although there may be non-Faradaic contributions to the coating growth.

A large volume uniform plasma generator for the experiments of electromagnetic wave propagation in plasma

International Nuclear Information System (INIS)

Yang Min; Li Xiaoping; Xie Kai; Liu Donglin; Liu Yanming

2013-01-01

A large volume uniform plasma generator is proposed for the experiments of electromagnetic (EM) wave propagation in plasma, to reproduce a “black out” phenomenon with long duration in an environment of the ordinary laboratory. The plasma generator achieves a controllable approximate uniform plasma in volume of 260 mm× 260 mm× 180 mm without the magnetic confinement. The plasma is produced by the glow discharge, and the special discharge structure is built to bring a steady approximate uniform plasma environment in the electromagnetic wave propagation path without any other barriers. In addition, the electron density and luminosity distributions of plasma under different discharge conditions were diagnosed and experimentally investigated. Both the electron density and the plasma uniformity are directly proportional to the input power and in roughly reverse proportion to the gas pressure in the chamber. Furthermore, the experiments of electromagnetic wave propagation in plasma are conducted in this plasma generator. Blackout phenomena at GPS signal are observed under this system and the measured attenuation curve is of reasonable agreement with the theoretical one, which suggests the effectiveness of the proposed method.

Plasma and blood volume in the calf from birth till 90 days of age

International Nuclear Information System (INIS)

Moellerberg, L.; Ekman, L.; Jacobsson, S.-O.

1975-01-01

Determinations of plasma volume were made of 9 clinically healthy Swedish Red and White calves from birth to 90 days of age by means of the isotop dilution technique. Commercially available 131 I labelled human serum albumin was used. Calculation of the total blood volume was based on the plasma volume and packed cell volume. The plasma and blood volumes increased per kg body weight in average 17 and 14 percent respectively from directly after birth to 24 hrs. old. From 1 to 90 days of age the plasma and blood volume fell steadily per kg body weight. Plasma volume expressed as a percentage of body weight was 5.3 percent at birth, 6.5 percent at 1 day old, and 4.9 percent at 90 days old. Corresponding values for blood were 8.4, 9.3 and 7.0 percent. (author)

Magnesium Oxide (MgO) pH-sensitive Sensing Membrane in Electrolyte-Insulator-Semiconductor Structures with CF4 Plasma Treatment.

Science.gov (United States)

Kao, Chyuan-Haur; Chang, Chia Lung; Su, Wei Ming; Chen, Yu Tzu; Lu, Chien Cheng; Lee, Yu Shan; Hong, Chen Hao; Lin, Chan-Yu; Chen, Hsiang

2017-08-03

Magnesium oxide (MgO) sensing membranes in pH-sensitive electrolyte-insulator-semiconductor structures were fabricated on silicon substrate. To optimize the sensing capability of the membrane, CF 4 plasma was incorporated to improve the material quality of MgO films. Multiple material analyses including FESEM, XRD, AFM, and SIMS indicate that plasma treatment might enhance the crystallization and increase the grain size. Therefore, the sensing behaviors in terms of sensitivity, linearity, hysteresis effects, and drift rates might be improved. MgO-based EIS membranes with CF 4 plasma treatment show promise for future industrial biosensing applications.

Dual effect of insulin on plasma volume and transcapillary albumin transport

DEFF Research Database (Denmark)

Hilsted, J; Christensen, N J

1992-01-01

vascular dilatation and increased muscle sympathetic nerve activity during a euglycaemic glucose clamp. During similar conditions insulin increased the transcapillary escape rate of albumin and reduced plasma volume. Insulin has also an indirect effect on vascular permeability during hypoglycaemia, which...... is mediated by the increase in plasma adrenaline. Adrenaline infusion increased haematocrit and decreased plasma volume and intravascular albumin mass. In contrast to insulin adrenaline did not increase the transcapillary escape rate of albumin. Total autonomic blockade during insulin-induced hypoglycaemia...... abolished the increase in haematocrit, but did not influence the decrease in plasma volume and the increase in the transcapillary escape rate of albumin. Insulin administration may also increase urinary albumin excretion, and this effect was observed during a euglycaemic clamp. The mechanism of the increase...

Data on the surface morphology of additively manufactured Ti-6Al-4V implants during processing by plasma electrolytic oxidation

NARCIS (Netherlands)

van Hengel, I.A.J. (Ingmar A.J.); M. Riool (Martijn); L.E. Fratila-Apachitei (L.); J. Witte-Bouma (Janneke); E. Farrell (Eric); A.A. Zadpoor (Amir Abbas); S.A.J. Zaat (Sebastiaan); I. Apachitei (I.)

2017-01-01

textabstractAdditively manufactured Ti-6Al-4V implants were biofunctionalized using plasma electrolytic oxidation. At various time points during this process scanning electron microscopy imaging was performed to analyze the surface morphology (van Hengel et al., 2017) [1]. This data shows the

Fluid-electrolyte shifts and thermoregulation: Rest and work in heat with head cooling.

Science.gov (United States)

Greenleaf, J E; Van Beaumont, W; Brock, P J; Montgomery, L D; Morse, J T; Shvartz, E; Kravik, S

1980-08-01

Plasma volume and thermoregulatory responses were measured, during head and neck cooling with a liquid-cooled neoprene headgear, in four men (21-43 years old) during 60 min of rest, 60 min of ergometer exercise (45% VO2 max), and 30 min of recovery in the supine position at 40.1 degrees C DBT and 40% rh. Compared with control (noncooling) responses, cooling decreased thigh sweating and increased mean skin temperature (Tsk) at rest, and attenuated the increases in thigh sweating by 0.26 mg/min x cm2 (-22.4%, p cooling facilitated the decreases in thigh sweat rate, heart rate, Tre, and forearm blood flow, and enhanced the increase in Tsk toward control levels. Cooling had no effect upon plasma protein, osmotic, or electrolyte shifts during rest, exercise, or recovery. Plasma volume (PV) loss during exercise was 11.2% without cooling and 10.9% with cooling. Cooling increased PV by 3% (p < 0.05) during rest, and this differential was maintained throughout the exercise and recovery periods.

Plasma response to electron energy filter in large volume plasma device

International Nuclear Information System (INIS)

Sanyasi, A. K.; Awasthi, L. M.; Mattoo, S. K.; Srivastava, P. K.; Singh, S. K.; Singh, R.; Kaw, P. K.

2013-01-01

An electron energy filter (EEF) is embedded in the Large Volume Plasma Device plasma for carrying out studies on excitation of plasma turbulence by a gradient in electron temperature (ETG) described in the paper of Mattoo et al. [S. K. Mattoo et al., Phys. Rev. Lett. 108, 255007 (2012)]. In this paper, we report results on the response of the plasma to the EEF. It is shown that inhomogeneity in the magnetic field of the EEF switches on several physical phenomena resulting in plasma regions with different characteristics, including a plasma region free from energetic electrons, suitable for the study of ETG turbulence. Specifically, we report that localized structures of plasma density, potential, electron temperature, and plasma turbulence are excited in the EEF plasma. It is shown that structures of electron temperature and potential are created due to energy dependence of the electron transport in the filter region. On the other hand, although structure of plasma density has origin in the particle transport but two distinct steps of the density structure emerge from dominance of collisionality in the source-EEF region and of the Bohm diffusion in the EEF-target region. It is argued and experimental evidence is provided for existence of drift like flute Rayleigh-Taylor in the EEF plasma

Hydrogenation of gold-related levels in silicon by electrolytic doping

International Nuclear Information System (INIS)

Pearton, S.J.; Hansen, W.L.; Haller, E.E.; Kahn, J.M.

1984-01-01

The deep gold-related donor and acceptor levels in silicon have been neutralized to several μm depth by introducing atomic hydrogen using an electrolytic method. Using phosphoric or sulfuric acid as the electrolyte, it is possible to dope the crystalline silicon with hydrogen at elevated temperatures (200--280 0 C) allowing direct comparison with other means of introduction, such as hydrogen plasma exposure. We find the electrolytic method is not as efficient as plasma treatment for the same conditions, possibly due to oxide formation during the immersion in the acid

99mTc-albumin can replace 125I-albumin to determine plasma volume repeatedly

DEFF Research Database (Denmark)

Bonfils, Peter K; Damgaard, Morten; Stokholm, Knud H

2012-01-01

OBJECTIVE: Plasma volume assessment may be of importance in several disorders. The purpose of the present study was to compare the reliability of plasma volume measurements by technetium-labeled human serum albumin ((99m)Tc-HSA) with a simultaneously performed plasma volume determination...... with iodine-labeled human serum albumin ((125)I-HSA). MATERIALS AND METHODS: In 15 healthy volunteers, simultaneous plasma volume measurements with (99m)Tc-HSA and (125)I-HSA were performed after ½ hour in the supine position. Blood samples were obtained 10, 15, 20, and 30 minutes after the injection...... for accurate retropolation from the plasma counts to time zero to correct for leakage of the isotopes from the circulation. RESULTS: The mean difference (bias) between plasma volume measured with (125)I-albumin and (99m)Tc-albumin was 8 ml (0.1 ml/kg) with limits of agreement (bias ±1.96 SD) ranging from -181...

Electrolyte-carbohydrate beverage prevents water loss in the early stage of high altitude training.

Science.gov (United States)

Yanagisawa, Kae; Ito, Osamu; Nagai, Satsuki; Onishi, Shohei

2012-01-01

To prevent water loss in the early stage of high altitude training, we focused on the effect of electrolyte-carbohydrate beverage (EC). Subjects were 16 male university students who belonged to a ski club. They had ski training at an altitude of 1,800 m. The water (WT) group drank only water, and the EC group drank only an electrolyte-carbohydrate beverage. They arrived at the training site in the late afternoon. The study started at 7 pm on the day of arrival and continued until noon of the 4(th) day. In the first 12 hours, 1 L of beverages were given. On the second and third days, 2.5 L of beverages were given. All subjects ate the same meals. Each morning while in fasting condition, subjects were weighed and blood was withdrawn for various parameters (hemoglobin, hematocrit, sodium, potassium and aldosterone). Urine was collected at 12 hour intervals for a total 60 hours (5 times). The urine volume, gravity, sodium and potassium concentrations were measured. Peripheral oxygen saturation and heart rate were measured during sleep with a pulse oximeter. Liquid intakes in both groups were similar, hence the electrolytes intake was higher in the EC group than in the WT group. The total urine volume was lower in the EC group than in the WT group, respectively (paltitude training may be effective in decreasing urinary output and preventing loss of blood plasma volume.

Data on the surface morphology of additively manufactured Ti-6Al-4V implants during processing by plasma electrolytic oxidation

NARCIS (Netherlands)

van Hengel, I.A.J.; Riool, Martijn; Fratila-Apachitei, E.L.; Witte-Bouma, Janneke; Farrell, Eric; Zadpoor, A.A.; Zaat, Sebastian A.J.; Apachitei, I.

2017-01-01

Additively manufactured Ti-6Al-4V implants were biofunctionalized using plasma electrolytic oxidation. At various time points during this process scanning electron microscopy imaging was performed to analyze the surface morphology (van Hengel et al., 2017) [1]. This data shows the changes in

Real-time imaging, spectroscopy, and structural investigation of cathodic plasma electrolytic oxidation of molybdenum

Energy Technology Data Exchange (ETDEWEB)

Stojadinović, Stevan, E-mail: sstevan@ff.bg.ac.rs; Tadić, Nenad; Šišović, Nikola M.; Vasilić, Rastko [Faculty of Physics, University of Belgrade, Studentski trg 12-16, 11000 Belgrade (Serbia)

2015-06-21

In this paper, the results of the investigation of cathodic plasma electrolytic oxidation (CPEO) of molybdenum at 160 V in a mixed solution of borax, water, and ethylene glycol are presented. Real-time imaging and optical emission spectroscopy were used for the characterization of the CPEO. During the process, vapor envelope is formed around the cathode and strong electric field within the envelope caused the generation of plasma discharges. The spectral line shape analysis of hydrogen Balmer line H{sub β} (486.13 nm) shows that plasma discharges are characterized by the electron number density of about 1.4 × 10{sup 21 }m{sup −3}. The electron temperature of 15 000 K was estimated by measuring molybdenum atomic lines intensity. Surface morphology, chemical, and phase composition of coatings formed by CPEO were characterized by scanning electron microscopy with energy dispersive x-ray spectroscopy and x-ray diffraction. The elemental components of CPEO coatings are Mo and O and the predominant crystalline form is MoO{sub 3}.

Effect of Nano-crystalline Ceramic Coats Produced by Plasma Electrolytic Oxidation on Corrosion Behavior of AA5083 Aluminum Alloy

International Nuclear Information System (INIS)

Thayananth, T.; Muthupandi, V.; Rao, S. R. Koteswara

2010-01-01

High specific strength offered by aluminum and magnesium alloys makes them desirable in modern transportation industries. Often the restrictions imposed on the usage of these alloys are due to their poor tribological and corrosion properties. However, their corrosion properties can be further enhanced by synthesizing ceramic coating on the substrate through Plasma Electrolytic Oxidation (PEO) process. In this study, nano-crystalline alumina coatings were formed on the surface of AA5083 aluminum alloy test coupons using PEO process in aqueous alkali-silicate electrolyte with and without addition of sodium aluminate. X-ray diffraction (XRD) studies showed that the crystallite size varied between 38 and 46 nm and α- and γ- alumina were the dominant phases present in the coatings. Corrosion studies by potentiodynamic polarization tests in 3.5% NaCl revealed that the electrolyte composition has an influence on the corrosion resistance of nano-crystalline oxide layer formed.

Prepregnancy low-plasma volume and predisposition to preeclampsia and fetal growth restriction

NARCIS (Netherlands)

Scholten, R.R.; Sep, S.; Peeters, L.; Hopman, M.T.E.; Lotgering, F.K.; Spaanderman, M.E.A.

2011-01-01

OBJECTIVE: To estimate whether recurrence risks of preeclampsia, preterm birth, and fetal growth restriction relate to prepregnancy plasma volume. METHODS: We conducted a retrospective cohort study in 580 formerly preeclamptic women and a control group. In all women we measured plasma volume

Plasma electrolytic oxidation of A1050 aluminium alloy in homogeneous silicate-alkaline electrolytes with edta{sup 4−} complexes of Fe, Co, Ni, Cu, La and Ba under alternating polarization conditions

Energy Technology Data Exchange (ETDEWEB)

Rogov, A.B., E-mail: alex-lab@bk.ru [Nikolaev Institute of Inorganic Chemistry, 3, Acad. Lavrentiev Ave., Novosibirsk, 630090 (Russian Federation); Scientific and Technical Centre “Pokrytie-A” (OOO), 15, Dzerzhinskogo Ave., Novosibirsk, 630015 (Russian Federation)

2015-11-01

This work is devoted to the synthesis of coatings containing a number of transition elements by plasma electrolytic oxidation (PEO) on aluminium A1050 alloy. The paper discusses PEO coatings obtained in silicate-alkaline electrolytes containing complexes of Fe, Co, Ni, Cu, La and Ba with ethylenediaminetetraacetic anion edta{sup 4−}. It is also focused on the chemical basis of the electrolyte components choice and their role in the process of PEO. Possible mechanism of coating formation process is also discussed. Alternating current mode (symmetrical sinusoidal current pulses, initial average current density - 100 mA cm{sup −2}) was used to produce the coatings. The PEO process was characterized by behaviours of the anodic and cathodic peak voltage curves. Coating surfaces and cross sections are studied by optical dark field microscopy and scanning electron microscopy, X-ray and energy dispersive analysis. - Highlights: • Alkaline homogeneous electrolyte with transition metal-edta{sup 4-} complexes. • Coatings contain Fe, Co, Ni, Cu, La, Ba elements in alumina-silica matrix. • Alternating symmetric sinusoidal current of 100 mA cm{sup −2} was applied. • Borax buffer solution and silicate passivating agent were used.

A Simple Method to Functionalize the Surface of Plasma Electrolytic Oxidation Produced TiO2 Coatings for Growing Hydroxyapatite

International Nuclear Information System (INIS)

Teng, Huan-Ping; Yang, Chia-Jung; Lin, Jia-Fu; Huang, Yu-Hsin; Lu, Fu-Hsing

2016-01-01

Highlights: • TiO 2 coatings with porous surfaces were produced by plasma electrolytic oxidation. • Simple pre-immersion in K 2 HPO 4 could functionalize the surfaces of the TiO 2 . • Such pre-immersion enhanced substantially the growth of hydroxyapatite in SBF. • Growth mechanisms of hydroxyapatite via the pre-immersion have been proposed. • MTT assay shows great osteoblast-like cell activity on the obtained hydroxyapatite. - Abstract: Conventionally, hydrothermal treatment was often used to modify the TiO 2 surface prior to the growth of hydroxyapatite (HA) that is one of the most important implant biomaterials. In this work, a simple pre-immersion of the obtained TiO 2 in a weak base, instead of the conventionally high pressure-temperature hydrothermal pre-treatment, was conducted prior to the growth of HA. Firstly, anatase TiO 2 coatings with porous surfaces were produced by plasma electrolytic oxidation with optimized processing parameters. X-ray diffraction patterns and field-emission microscopy reveal that the anatase TiO 2 films with porous surfaces were produced by plasma electrolytic oxidation. Subsequently, the films were pre-immersed in 0.1–2 M K 2 HPO 4 solutions for only 10 min. Fourier transform infrared spectroscopy shows that the −OH functional groups were generated after such pre-immersion, which could enhance significantly the growth of a single phase of HA in simulated body fluid (SBF). Growth mechanisms of HA via the pre-immersion treatment and soaking in SBF have been proposed. Moreover, the proliferation rate and attachment of the MG-63 osteoblast cells were greatly enhanced on the obtained HA compared to that without the immersion pre-treatment from the MTT assay and morphology analyses. This simple immersion pre-treatment evidently provides an easy route for the growth of HA and has great potential for biomedical applications.

Corrosion-electrochemical characteristics of oxide-carbide and oxide-nitride coatings formed by electrolytic plasma

International Nuclear Information System (INIS)

Tomashov, N.D.; Chukalovskaya, T.V.; Medova, I.L.; Duradzhi, V.N.; Plavnik, G.M.

1990-01-01

The composition, structure, microhardness and corrosion-electrochemical properties of oxide-carbide and oxide-nitride coatings on titanium in 5n H 2 SO 4 , 50 deg, produced by the method of chemical-heat treatment in electrolytic plasma, containing saturation components of nitrogen and carbon, were investigated. It is shown that the coatings produced have increased hardness, possess high corrosion resistance in sulfuric acid solution at increased temperature, as to their electrochemcial behaviour they are similar to titanium carbide and nitride respectively. It is shown that high corrosion resistance is ensured by electrochemical mechanism of the oxide-carbide and oxide-nitride coating protection

Moderator's view: High-volume plasma exchange: pro, con and consensus.

Science.gov (United States)

Kaplan, Andre A

2017-09-01

I have been asked to comment on the pro and con opinions regarding high-volume plasma exchange. The authors of both positions have provided cogent arguments and a reasonable approach to choosing the exchange volume for any given therapeutic plasma exchange. The major issue of relevance in this discussion is the nature of the toxins targeted for removal. These parameters include molecular weight, the apparent volume of distribution, the degree of protein binding, the biologic and chemical half-life, and the severity and rapidity of its toxicity. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

A spectroscopic and microstructural study of oxide coatings produced on a Ti–6Al–4V alloy by plasma electrolytic oxidation

International Nuclear Information System (INIS)

Hussein, R.O.; Nie, X.; Northwood, D.O.

2012-01-01

Highlights: ► PEO (plasma electrolytic oxidation) for production of oxide coatings on a Ti–6Al–4V alloy. ► Two different current modes namely pulsed unipolar and bipolar was used. ► Optical emission spectroscopy (OES) was used to characterize the PEO plasma. ► This is the first attempt to characterize spectroscopically the PEO plasma of Ti and its alloys. ► The discharge behavior effect on the formation and structure of the coating was determined. - Abstract: In this study, we have used PEO (plasma electrolytic oxidation) for the production of oxide coatings on a Ti–6Al–4V alloy at two different current modes, namely pulsed unipolar and bipolar. Optical emission spectroscopy (OES) in the visible and near UV band (280–800 nm) was used to characterize the PEO plasma. The emission spectra were recorded and the plasma temperature profile versus processing time was constructed using a line intensity ratios method. The aim of this work was to study the effect of the process parameters, including current mode and pulse duration time, on the plasma characteristics, surface morphology and microstructure and corrosion resistance of oxides grown on Ti–6Al–4V by PEO process. Scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDS) and X-ray diffraction (XRD) were used to study the coating microstructure, morphology and phase composition. The corrosion resistance of the coated and uncoated samples was examined by potentiodynamic polarization in a 3.5% NaCl solution. It was found that the plasma temperature profiles are significantly influenced by changing the current mode from unipolar to bipolar. The strongest discharges that are initiated at the interface between the substrate and the coating can be reduced or eliminated by using a bipolar current mode. This produces a thinner, denser and more corrosion-resistant coating.

The effect of chronic erythrocytic polycythemia and high altitude upon plasma and blood volumes.

Science.gov (United States)

Burton, R. R.; Smith, A. H.

1972-01-01

Comparison of two kinds of physiological chronic erythrocytic polycythemias in order to differentiate the specific effect of erythrocytic polycythemia from the general effects of high altitude upon the plasma volume. The two kinds were produced hormonally in female chickens, at sea level, or by protracted high-altitude exposures. It appears that the vascular system of the body may account for an increase in red blood cell mass either by reduction in plasma volume, or by no change in plasma volume, resulting in differential changes in total blood volumes.

Effects of cathode current density on structure and corrosion resistance of plasma electrolytic oxidation coatings formed on ZK60 Mg alloy

International Nuclear Information System (INIS)

Su Peibo; Wu Xiaohong; Guo Yun; Jiang Zhaohua

2009-01-01

Current density is a key factor in plasma electrolytic oxidation (PEO) process. The aim of this paper is to study the effects of cathode current density on the composition, morphology, and corrosion resistance of ceramic coatings on ZK60 magnesium alloy prepared through bi-polar plasma electrolytic oxidation in Na 3 PO 4 solution. The phase composition, morphology, and corrosion resistance were studied by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Electrochemical Impedance Spectroscopy (EIS) and potentiodynamic polarization in 3.5% NaCl solution. It is found that the as-produced coatings are only composed of MgO. The increase of cathode current density made the coatings less porous and more compact. Analysis of EIS and potentiodynamic polarization technique on the samples shows that the corrosion resistance of the coated samples is better than that of ZK60 magnesium alloy, and that a bigger cathode current density can improve the corrosion resistance of as-prepared coatings.

Mathematical modeling of the lithium, thionyl chloride static cell. I. Neutral electrolyte. II - Acid electrolyte

Energy Technology Data Exchange (ETDEWEB)

Tsaur, K.C.; Pollard, R.

1984-05-01

Mathematical models are presented for a Li-LiAlCl4/SOCl2-C static cell with neutral electrolyte and a Li/SOCl2-C static cell with acid electrolyte. The model for the Li-LiAlCl4/SOCl2-C cell with neutral solution predicts that high internal resistance can develop in the positive electrode as a result of low local porosities which are, in turn, caused by large-volume, solid reaction products. Consequently, the maximum usable cell capacity is dictated by the nonuniformity of the reaction distribution at the front of the positive electrode. In many respects, a cell with acid electrolyte can be regarded as a combination of an equivalent neutral electrolyte system and an acid reservoir. The model for the Li/SOCl2 cell suggests that the cell life depends primarily on the quantity of acid added to the electrolyte. 58 references.

Mathematical modeling of the lithium, thionyl chloride static cell. I - Neutral electrolyte. II - Acid electrolyte

Science.gov (United States)

Tsaur, K.-C.; Pollard, R.

1984-05-01

Mathematical models are presented for a Li-LiAlCl4/SOCl2-C static cell with neutral electrolyte and a Li/SOCl2-C static cell with acid electrolyte. The model for the Li-LiAlCl4/SOCl2-C cell with neutral solution predicts that high internal resistance can develop in the positive electrode as a result of low local porosities which are, in turn, caused by large-volume, solid reaction products. Consequently, the maximum usable cell capacity is dictated by the nonuniformity of the reaction distribution at the front of the positive electrode. In many respects, a cell with acid electrolyte can be regarded as a combination of an equivalent neutral electrolyte system and an acid reservoir. The model for the Li/SOCl2 cell suggests that the cell life depends primarily on the quantity of acid added to the electrolyte.

Effects of Weightlessness on Human Fluid and Electrolyte Physiology

Science.gov (United States)

Leach, Carolyn S.; Johnson, Philip C., Jr.

1991-01-01

The changes that occur in human fluid and electrolyte physiology during the acute and adaptive phases of adaptation to spaceflight are summarized. A number of questions remain to be answered. At a time when plasma volume and extracellular fluid volume are contracted and salt and water intake is unrestricted. ADH does not correct the volume deficit and serum sodium decreases. Change in secretion or activity of a natriuretic factor during spaceflight is one possible explanation. Recent identification of a polypeptide hormone produced in cardiac muscle cells which is natiuretic, is hypotensive, and has an inhibitory effect on renin and aldosterone secretion has renewed interest in the role of a natriuretic factor. The role of this atrial natriuretic factor (ANF) in both long- and short-term variation in extracellular volumes and in the inability of the kidney to bring about an escape from the sodium-retaining state accompanying chronic cardiac dysfunction makes it reasonable to look for a role of ANF in the regulation of sodium during exposure to microgravity. Prostaglandin-E is another hormone that may antagonize the action of ADH. Assays of these hormones will be performed on samples from crew members in the future.

Plasma volume methodology: Evans blue, hemoglobin-hematocrit, and mass density transformations

Science.gov (United States)

Greenleaf, J. E.; Hinghofer-Szalkay, H.

1985-01-01

Methods for measuring absolute levels and changes in plasma volume are presented along with derivations of pertinent equations. Reduction in variability of the Evans blue dye dilution technique using chromatographic column purification suggests that the day-to-day variability in the plasma volume in humans is less than + or - 20 m1. Mass density determination using the mechanical-oscillator technique provides a method for measuring vascular fluid shifts continuously for assessing the density of the filtrate, and for quantifying movements of protein across microvascular walls. Equations for the calculation of volume and density of shifted fluid are presented.

[Measurement of maternal plasma volume during pregnancy].

Science.gov (United States)

Uzan, S; Beaufils, M; Uzan, M; Donsimoni, R; Mareck, A; Salat-Baroux, J; Sureau, C

1988-02-01

An increased maternal plasma volume (PV) is a characteristic phenomenon of normal pregnancy, which may be related to a physiological decrease of peripheral resistances. The authors have studied the plasma volume of 1,105 patients distributed as follows: normal (387), permanently hypertensive patients (84), hypertensive patients during pregnancy (390), patients with apparently isolated RCIU (154) or with a pathological past-history during previous pregnancies (90). It appears that the PV is a sign of a severe HBP, and presents a rather early and good predictive value regarding the weight of the fetus and some complications such as severe UCIU and fetal death in utero. In case of pathological past events or pre-existing hypertension, the PV enables to differentiate rather well patients who will be prone to a complicated pregnancy. In view of these results, utilization and interpretation criteria of this parameter during pregnancies with hypertension or pregnancies in which there is a suspicion or a risk of intra-uterine growth delay, are defined.

High-compactness coating grown by plasma electrolytic oxidation on AZ31 magnesium alloy in the solution of silicate–borax

International Nuclear Information System (INIS)

Shen, M.J.; Wang, X.J.; Zhang, M.F.

2012-01-01

Highlights: ► The MgO ceramic coating has been prepared on the surface of AZ31 magnesium alloy by plasma electrolytic oxidation in the borax-doped silicate system. ► Boron element exists in the PEO films in the form of noncrystal. ► The microhardness and compactness of doped ceramic coating are much higher than that of the substrate and undoped ceramic coating, and this doped coated sample shows better wear-resisting property. - Abstract: A ceramic coating was formed on the surface of AZ31 magnesium alloy by plasma electrolytic oxidation (PEO) in the silicate solution with and without borax doped. The composition, morphology, elements and roughness as well as mechanical property of the coating were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and reciprocal-sliding tribometer. The results show that the PEO coating is mainly composed of magnesia. When using borax dope, boron element is permeating into the coating and the boron containing phase exist in the form of amorphous. In addition, the microhardness and compactness of the PEO coating are improved significantly due to doped borax.

Dual Electrolytic Plasma Processing for Steel Surface Cleaning and Passivation

Science.gov (United States)

Yang, L.; Zhang, P.; Shi, J.; Liang, J.; Tian, W. B.; Zhang, Y. M.; Sun, Z. M.

2017-10-01

To remove the rust on rebars and passivate the fresh surfaces, electrodes reversing electrolytic plasma processing (EPP) was proposed and conducted in a 10 wt.% Na2CO3 aqueous solution. The morphology and the composition of the surface were investigated by SEM and XPS. Experimental results show that the rust on the surface was removed effectively by cathode EPP, and a passive film containing Cr2O3 was achieved by the succeeding anode EPP treatment, by a simple operation of reversing the bias. The corrosion resistance was evaluated in a 3.5 wt.% NaCl aqueous solution using an electrochemical workstation. In comparison, the corrosion resistance was improved by the succeeding anode EPP treatment, which is evidenced by a positive shift of the open-circuit potential, an increase in the electrochemical impedance representing the inner layer by 76.8% and the decrease in the corrosion current density by 49.6%. This is an effective and environment-friendly technique to clean and passivate rebars and similar steel materials.

Study of the effect of Pyrophosphate in low voltage Plasma Electrolytic Oxidation on the corrosion resistance of AZ31B Magnesium alloy

International Nuclear Information System (INIS)

Yun, Jae Gon; Kim, Eng Chan; Kim, Ki Hong

2016-01-01

In this study, low voltage Plasma Electrolytic Oxidation (PEO) was utilized to eliminate the drawbacks of high voltage PEO such as high cost, dimensional deformation, and porosity. Low voltage PEO produces a thin coating, which leads to low corrosion resistance. In order to solve this problem, 0.1⁓0.6 M pyrophosphates were added to a bath containing 1.4 M NaOH and 0.35 M Na_2SiO_3.PEO at 70V was conducted at 25℃ for 3 minutes. The chemical composition, morphology, and corrosion resistance of the anodized coating were analyzed. The anodized film was composed of MgO, Mg_2SiO_4, and Mg_2O_7P_2. Themorphology of the film showed a inappropriately dense structure and low porosity in the anodized layers. It is found that low voltage Plasma Electrolytic Oxidation in cooperation with phosphating treatment can provide good corrosion protection for the AZ31B magnesium alloy.

Study of the effect of Pyrophosphate in low voltage Plasma Electrolytic Oxidation on the corrosion resistance of AZ31B Magnesium alloy

Energy Technology Data Exchange (ETDEWEB)

Yun, Jae Gon; Kim, Eng Chan [Yeungnam University, Gyeongsan (Korea, Republic of); Kim, Ki Hong [Catholic University of Daegu, Gyeongsan (Korea, Republic of)

2016-01-15

In this study, low voltage Plasma Electrolytic Oxidation (PEO) was utilized to eliminate the drawbacks of high voltage PEO such as high cost, dimensional deformation, and porosity. Low voltage PEO produces a thin coating, which leads to low corrosion resistance. In order to solve this problem, 0.1⁓0.6 M pyrophosphates were added to a bath containing 1.4 M NaOH and 0.35 M Na{sub 2}SiO{sub 3}.PEO at 70V was conducted at 25℃ for 3 minutes. The chemical composition, morphology, and corrosion resistance of the anodized coating were analyzed. The anodized film was composed of MgO, Mg{sub 2}SiO{sub 4}, and Mg{sub 2}O{sub 7}P{sub 2}. Themorphology of the film showed a inappropriately dense structure and low porosity in the anodized layers. It is found that low voltage Plasma Electrolytic Oxidation in cooperation with phosphating treatment can provide good corrosion protection for the AZ31B magnesium alloy.

Impact of the time window on plasma volume measurement with indocyanine green

International Nuclear Information System (INIS)

Jacob, M; Chappell, D; Conzen, P; Finsterer, U; Rehm, M; Krafft, A; Becker, B F

2008-01-01

Recent reports have questioned the accuracy of the indocyanine green dilution technique for measuring plasma volume. Our objective was to evaluate the impact of different time windows for monoexponential extrapolation. We retrospectively analysed 31 indocyanine green decay curves to investigate the problem in principle (group 1) and prospectively performed another 21 plasma volume measurements to estimate its practical impact (group 2). To monoexponentially extrapolate back to the specific extinction at the time of dye injection, two different time windows were applied to each decay curve, comparing the plasma volumes resulting from sampling within a short (≤5 min) versus a longer (>5 min) period of time. Extrapolating back from the longer period led to a higher apparent plasma volume relative to the shorter period in both groups, the difference being 348 ± 171 ml (group 1) and 384 ± 131 ml (group 2; mean ± SD; p < 0.05 each). This result was due to a reliable monoexponentiality of decay only up to the 5th min after dye injection. Thus, to estimate the initial distribution space of indocyanine green via monoexponential extrapolation, the first linear kinetic of indocyanine green decay should be taken

IMPLEMENTATION OF A SWITCHED POWER SUPPLY FOR THE PLASMA ELECTROLYTIC OXIDATION TECHNIQUE

Directory of Open Access Journals (Sweden)

Fernando Gordillo-Delgado

2017-07-01

Full Text Available A switched-mode power supply was implemented for using in the Plasma Electrolytic Oxidation (PEO technique. The electronic devices are inexpensive and ordinarily used, which facilitates the construction of the system. A MICROCHIP microcontroller was used for generating a digital signal with frequency and duty cycle control; a capacitor bank and a diode bridge were also used for rectifying the input signal from the electrical network. The management of the output voltage was made with an arrangement of MOSFET transistors in the "low side" configuration; the measurement of the current was made with a Hall Effect sensor and using the USB communication the data was sent to a computer for visualization with a LabVIEW algorithm. The power supply was tested for creating microcavities in a titanium sheet with the aim of forming nanostructures of titanium dioxide.

Plasma volume changes during hypoglycaemia: the effect of arterial blood sampling

DEFF Research Database (Denmark)

Hilsted, J; Bendtsen, Flemming; Christensen, N J

1990-01-01

To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... hypoglycaemia. The magnitude of the changes in arterial and venous blood were not significantly different. These results indicate that the above changes in blood volume and composition are whole-body phenomena: furthermore, the major part of the changes are likely to occur in tissues other than upper extremity...... of albumin in arterial and venous blood in seven healthy subjects before and during insulin-induced hypoglycaemia. In both vascular sites blood 51Cr content and the haematocrit increased, plasma volume and intravascular albumin content decreased and the transcapillary escape rate of albumin increased during...

Effect of additive on electrochemical corrosion properties of plasma electrolytic oxidation coatings formed on CP Ti under different processing frequency

Energy Technology Data Exchange (ETDEWEB)

Babaei, Mahdi, E-mail: mahdi.babaei@ut.ac.ir; Dehghanian, Changiz; Vanaki, Mojtaba

2015-12-01

Highlights: • PEO coatings formed on Cp Ti from phosphate electrolyte with zirconate additive. • The SEM results provide information of microdischarge behavior. • The effect of additive on structure and long-term corrosion behavior was investigated. • The additive influence on coating performance varies with processing frequency. - Abstract: The plasma electrolytic oxidation (PEO) coating containing zirconium oxide was fabricated on CP Ti at different processing frequencies viz., 100 Hz and 1000 Hz in a (Na{sub 2}ZrO{sub 3}, Na{sub 2}SiO{sub 3})-additive containing NaH{sub 2}PO{sub 4}-based solution, and long-term electrochemical corrosion behavior of the coatings was studied using electrochemical impedance spectroscopy (EIS) in 3.5 wt.% NaCl solution. Electrochemical degradation behavior of two-layered coatings formed at different frequencies was turned out to be governed by concentration of electrolyte additive. With increasing additive concentration, the coating obtained at frequency of 1000 Hz exhibited enhanced corrosion resistance. However, corrosion resistance of the coating prepared at 100 Hz was found to decrease with increased additive, which was attributed to intensified microdischarges damaging the protective effect of inner layer. Nevertheless, the electrolyte additive was found to mitigate the long-term degradation of the coatings to a significant extent.

Hydroxyapatite coatings containing Zn and Si on Ti-6Al-4Valloy by plasma electrolytic oxidation

Science.gov (United States)

Hwang, In-Jo; Choe, Han-Cheol

2018-02-01

In this study, hydroxyapatite coatings containing Zn and Si on Ti-6Al-4Valloy by plasma electrolytic oxidation were researched using various experimental instruments. The pore size is depended on the electrolyte concentration and the particle size and number of pore increase on surface part and pore part. In the case of Zn/Si sample, pore size was larger than that of Zn samples. The maximum size of pores decreased and minimum size of pores increased up to 10Zn/Si and Zn and Si affect the formation of pore shapes. As Zn ion concentration increases, the size of the particle tends to increase, the number of particles on the surface part is reduced, whereas the size of the particles and the number of particles on pore part increased. Zn is mainly detected at pore part, and Si is mainly detected at surface part. The crystallite size of anatase increased as the Zn ion concentration, whereas, in the case of Si ion added, crystallite size of anatase decreased.

Fractal approach to surface roughness of TiO{sub 2}/WO{sub 3} coatings formed by plasma electrolytic oxidation process

Energy Technology Data Exchange (ETDEWEB)

Rožić, L.J., E-mail: ljrozic@nanosys.ihtmbg.ac.rs [University of Belgrade, IChTM-Department of Catalysis and Chemical Engineering, Njegoševa 12, Belgrade (Serbia); Petrović, S.; Radić, N. [University of Belgrade, IChTM-Department of Catalysis and Chemical Engineering, Njegoševa 12, Belgrade (Serbia); Stojadinović, S. [University of Belgrade, Faculty of Physics, Studentski trg 12-16, Belgrade (Serbia); Vasilić, R. [Faculty of Environmental Governance and Corporate Responsibility, Educons University, Vojvode Putnika 87, Sremska Kamenica (Serbia); Stefanov, P. [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Sofia 1113 (Bulgaria); Grbić, B. [University of Belgrade, IChTM-Department of Catalysis and Chemical Engineering, Njegoševa 12, Belgrade (Serbia)

2013-07-31

In this study, we have shown that atomic force microscopy is a powerful technique to study the fractal parameters of TiO{sub 2}/WO{sub 3} coatings prepared by plasma electrolytic oxidation (PEO) process. Since the surface roughness of obtained oxide coatings affects their physical properties, an accurate description of roughness parameters is highly desirable. The surface roughness, described by root mean squared and arithmetic average values, is analyzed considering the scans of a series of atomic force micrographs. The results show that the oxide coatings exhibit lower surface roughness in initial stage of PEO process. Also, the surfaces of TiO{sub 2}/WO{sub 3} coatings exhibit fractal behavior. Positive correlation between the fractal dimension and surface roughness of the surfaces of TiO{sub 2}/WO{sub 3} coatings in initial stage of PEO process was found. - Highlights: • TiO{sub 2}/WO{sub 3} coatings were obtained by plasma electrolytic oxidation. • Oxide coatings exhibit lower surface roughness in initial stage of process. • The surfaces of TiO{sub 2}/WO{sub 3} coatings exhibit fractal behavior.

Nanoporous hybrid electrolytes

KAUST Repository

Schaefer, Jennifer L.

2011-01-01

Oligomer-suspended SiO2-polyethylene glycol nanoparticles are studied as porous media electrolytes. At SiO2 volume fractions, , bracketing a critical value y ≈ 0.29, the suspensions jam and their mechanical modulus increase by more than seven orders. For >y, the mean pore diameter is close to the anion size, yet the ionic conductivity remains surprisingly high and can be understood, at all , using a simple effective medium model proposed by Maxwell. SiO 2-polyethylene glycol hybrid electrolytes are also reported to manifest attractive electrochemical stability windows (0.3-6.3 V) and to reach a steady-state interfacial impedance when in contact with metallic lithium. © 2010 The Royal Society of Chemistry.

A model for steady-state large-volume plasma generation

International Nuclear Information System (INIS)

Uhm, H.S.; Miller, J.D.; Schneider, R.F.

1991-01-01

In this paper, a simple, new scheme to generate a uniform, steady-state, large-volume plasma is presented. The weakly magnetized plasma is created by direct ionization of the background gas by low-energy electrons generated from thermionic filaments. An annular arrangement of the filaments ensures a uniform plasma density in the radial direction as predicted by theory. Experiments have been performed to characterize the plasma generated in such a configuration. In order to explain the experimental observation, we develop a bulk plasma theory based on plasma transport via cross-field diffusion. As assumed in the theoretical model, the experimental measurements indicate a uniform plasma density along the axis. Both the theory and experiment indicate that the plasma density is a function of the square of the external magnetic field. The theory also predicts the plasma density to be proportional to the neutral density to the two-thirds power in agreement with the experimental data. We also observe the experimental data to agree remarkably well with theoretical prediction for a broad range of system parameters

Noninvasive in vivo plasma volume and hematocrit in humans: observing long-term baseline behavior to establish homeostasis for intravascular volume and composition

Science.gov (United States)

Dent, Paul; Deng, Bin; Goodisman, Jerry; Peterson, Charles M.; Narsipur, Sriram; Chaiken, J.

2016-04-01

A new device incorporating a new algorithm and measurement process allows simultaneous noninvasive in vivo monitoring of intravascular plasma volume and red blood cell volume. The purely optical technique involves probing fingertip skin with near infrared laser light and collecting the wavelength shifted light, that is, the inelastic emission (IE) which includes the unresolved Raman and fluorescence, and the un-shifted emission, that is, the elastic emission (EE) which includes both the Rayleigh and Mie scattered light. Our excitation and detection geometry is designed so that from these two simultaneous measurements we can calculate two parameters within the single scattering regime using radiation transfer theory, the intravascular plasma volume fraction and the red blood cell volume fraction. Previously calibrated against a gold standard FDA approved device, 2 hour monitoring sessions on three separate occasions over a three week span for a specific, motionless, and mostly sleeping individual produced 3 records containing a total of 5706 paired measurements of hematocrit and plasma volume. The average over the three runs, relative to the initial plasma volume taken as 100%, of the plasma volume±1σ was 97.56+/-0.55 or 0.56%.For the same three runs, the average relative hematocrit (Hct), referenced to an assumed initial value of 28.35 was 29.37+/-0.12 or stable to +/-0.4%.We observe local deterministic circulation effects apparently associated with the pressure applied by the finger probe as well as longer timescale behavior due to normal ebb and flow of internal fluids due to posture changes and tilt table induced gravity gradients.

Application of atmospheric-pressure plasma jet processed carbon nanotubes to liquid and quasi-solid-state gel electrolyte supercapacitors

Science.gov (United States)

Kuok, Fei-Hong; Kan, Ken-Yuan; Yu, Ing-Song; Chen, Chieh-Wen; Hsu, Cheng-Che; Cheng, I.-Chun; Chen, Jian-Zhang

2017-12-01

We use a dc-pulse nitrogen atmospheric-pressure plasma jet (APPJ) to calcine carbon nanotubes (CNTs) pastes that are screen-printed on carbon cloth. 30-s APPJ treatment can efficiently oxidize and vaporize the organic binders, thereby forming porous structures. As indicated by X-ray photoelectron spectroscopy (XPS) and electron probe microanalysis (EPMA), the oxygen content decreases after APPJ treatment owing to the oxidation and vaporization of ethyl cellulose, terpineol, and ethanol. Nitrogen doping was introduced to the materials by the nitrogen APPJ. APPJ-calcination improves the wettability of the CNTs printed on carbon cloth, as evidenced by water contact angle measurement. Raman spectroscopy indicates that reactive species of nitrogen APPJ react violently with CNTs in only 30-s APPJ processing time and introduce defects and/or surface functional groups on CNTs. Carbon cloths with calcined CNT layers are used as electrodes for liquid and quasi-solid-state electrolyte supercapacitors. Under a cyclic voltammetry test with a 2 mV/s potential scan rate, the specific capacitance is 73.84 F/g (areal capacitance = 5.89 mF/cm2) with a 2 M KCl electrolyte and 66.47 F/g (areal capacitance = 6.10 mF/cm2) with a H2SO4/polyvinyl alcohol (PVA) gel electrolyte.

Improved the accuracy of 99mTc-MAG3 plasma clearance method. The problem of the calculated plasma volume and its modification

International Nuclear Information System (INIS)

Watanabe, Nami; Komatani, Akio; Yamaguchi, Koichi; Takahashi, Kazuei

1998-01-01

The 99m Tc-MAG 3 plasma clearance method (MPC method), reported by Oriuchi et al., is a simple and useful count-based gamma camera method for calculating the 99m Tc-MAG 3 plasma clearance (CL MAG ). However, a discrepancy of CL MAG calculated by MPC method (MPC-CL MAG ) from the tubular extraction rate (TER) calculated by Russell's single-sample clearance determination (Russell-TER) was noted. The calculated plasma volume is assumed to be the cause. Since the plasma volume is reported to have a linear correlation with body surface area, Dissmann's formula was applied to calculate the plasma volume. Then Dissmann's formula was replaced by Ogawa's formula in the MPC method, and the procedure was then called the modified MPC method. The CL MAG were obtained using MPC method, modified MPC method and the TER was obtained Russell's method in 95 patients with urological disorders. Then the MPC-CL MAG and modified MPC-CL MAG were compared with Russell-TER. Comparison of the MPC-CL MAG with the Russell-TER demonstrated a coefficient of correlation of 0.82, but dissociation of the slope of regression lines was found between males and females. The modified MPC-CL MAG improved the coefficient of correlation to 0.92, and diminished the dissociation of the slope of regression lines between males and females. We verified that the dissociation was due to the plasma volume calculated by Ogawa's formula. Ogawa's formula included hematocrit, body weight, body height and different coefficients for gender. The plasma volume calculated by Ogawa's formula were lower in males and higher in females than that calculated by Dissmann's formula. And marked discrepancy in the plasma volume in patients with a body surface area below 0.5 m 2 was observed. So the MPC method might become more accurate by substituting Dissmann's formula for Ogawa's formula resoluting in a method that is applicable to both males and females, children and adults in clinical use. (author)

Fabrication of Coatings on the Surface of Magnesium Alloy by Plasma Electrolytic Oxidation Using ZrO2 and SiO2 Nanoparticles

Directory of Open Access Journals (Sweden)

S. V. Gnedenkov

2015-01-01

Full Text Available Results of investigation of the incorporation of zirconia and silica nanoparticles into the coatings formed on magnesium alloy by plasma electrolytic oxidation are presented. Comprehensive research of electrochemical and mechanical properties of obtained coatings was carried out. It was established that the polarization resistance of the samples with a coating containing zirconia nanoparticles is two times higher than that for the sample with base PEO layer. One of the important reasons for improving the protective properties of coatings formed in electrolytes containing nanoparticles consists in enhanced morphological characteristics, in particular, the porosity decrease and increase of thickness and resistivity (up to two orders of magnitude for ZrO2-containing coating of porousless sublayer in comparison with base PEO layer. Incorporation of silica and zirconia particles into the coating increases the mechanical performances. The layers containing nanoparticles have greater hardness and are more wear resistant in comparison with the coatings formed in the base electrolyte.

Characterization of coatings formed on AZX magnesium alloys by plasma electrolytic oxidation

Science.gov (United States)

Anawati, Anawati; Gumelar, Muhammad Dikdik

2018-05-01

Plasma Electrolytic Oxidation (PEO) is an electrochemical anodization process which involves the application of a high voltage to create intense plasma on a metal surface to form a ceramic type of oxide. The resulted coating exhibits high wear resistance and good corrosion barrier which are suitable to enhance the performance of biodegradable Mg alloys. In this work, the role of alloying element Ca in modifying the characteristics of PEO layer formed on AZ61 series magnesium alloys was investigated. PEO treatment was conducted on AZ61, AZX611, and AZX612 alloys in 0.5 M Na3PO4 solution at a constant current of 200 A/m2 at 25°C for 8 min. The resulted coatings were characterized by field emission-scanning electron microscope (FESEM), X-ray diffraction spectroscopy (XRD), and X-ray fluorescence spectroscopy (XRF), as well as hardness test. The presence of alloying element Ca in the AZ61 alloys accelerated the PEO coatings formation without altering the coating properties significantly. The coating formed on AZX specimen was slightly thicker ( 14-17 µm) than that of formed onthe AZ specimens ( 13 µm). Longer exposure time to plasma discharge was the reason for faster thickening of the coating layer on AZX specimen. XRD detected a similar crystalline oxide phase of Mg3(PO4)2 in the oxide formed on all of the specimens. Zn was highly incorporated in the coatings with a concentration in the range 24-30 wt%, as analyzed by XRF. Zn compound might exist in amorphous phases. The microhardness test on the coatings revealed similar average hardness 124 HVon all of the specimens.

Changes of hormones regulating electrolyte metabolism after space flight and hypokinesia

Science.gov (United States)

Macho, L.; Fickova, M.; Lichardus, B.; Kvetnansky, R.; Carrey, R. M.; Grigoriev, A.; Popova, I. A.; Tigranian, R. A.; Noskov, V. B.

The changes of hormones in plasma involved in the body fluid regulation were studied in human subjects during and after space flights in relation to redistribution of body fluids in the state of weightlessness. Since hypokinesia was used as a model for simulation of some effects of the stay in microgravity the plasma hormone levels in rats exposed to hypokinesia were also investigated. Plasma aldosterone values showed great individual variations during the first inflight days, the increased levels were observed with prolongation of space flights. The important elevation was found in the recovery period, however it was interesting to note, that in some cosmonauts with repeated exposure to space flight, the postflight plasma aldosterone levels were not elevated. The urine excretion of aldosterone was increased inflight, however in postflight period the decrease or increase were found in the first 1-5 days. The increase of plasma renin activity was observed in flight and postflight period. The rats were exposed to hypokinesia (forced restriction of motor activity) for 1, 7 and 60 days and urine was collected during last 24 hours. The animals were sacrificed and the concentration of electrolytes and of levels of corticosterone aldosteron (A), ANF and plasma-renin activity (PRA) were determined in plasma. In urine excretion of sodium and potassium were estimated. An important increase of plasma renin activity and aldosterone concentration was found after short-term hypokinesia (1 day). These hormonal values appear to decrease with time (7 days) and are not significantly different from controls after long-term hypokinesia (60 days). A decrease of values ANF in plasma was observed after 1 and 7 days hypokinesia. After prolonged hypokinesia a decrease of sodium plasma concentration was observed. The excretion of sodium in urine was higher in long-term hypokinetic animals. There were no significant changes of plasma potassium levels in rats exposed to hypokinesia, however

Low plasma volume coincides with sympathetic hyperactivity and reduced baroreflex sensitivity in formerly preeclamptic patients.

NARCIS (Netherlands)

Courtar, D.A.; Spaanderman, M.E.A.; Aardenburg, R.; Janssen, B.J.; Peeters, L.L.

2006-01-01

BACKGROUND: Preeclampsia is associated with enhanced sympathetic activity as well as subnormal plasma volume. Meanwhile, in over 50% of these complicated pregnancies, the subnormal plasma volume has been found to persist for a prolonged period after pregnancy. The objective of this study is to test

What is the fundamental ion-specific series for anions and cations? Ion specificity in standard partial molar volumes of electrolytes and electrostriction in water and non-aqueous solvents.

Science.gov (United States)

Mazzini, Virginia; Craig, Vincent S J

2017-10-01

The importance of electrolyte solutions cannot be overstated. Beyond the ionic strength of electrolyte solutions the specific nature of the ions present is vital in controlling a host of properties. Therefore ion specificity is fundamentally important in physical chemistry, engineering and biology. The observation that the strengths of the effect of ions often follows well established series suggests that a single predictive and quantitative description of specific-ion effects covering a wide range of systems is possible. Such a theory would revolutionise applications of physical chemistry from polymer precipitation to drug design. Current approaches to understanding specific-ion effects involve consideration of the ions themselves, the solvent and relevant interfaces and the interactions between them. Here we investigate the specific-ion effects trends of standard partial molar volumes and electrostrictive volumes of electrolytes in water and eleven non-aqueous solvents. We choose these measures as they relate to bulk properties at infinite dilution, therefore they are the simplest electrolyte systems. This is done to test the hypothesis that the ions alone exhibit a specific-ion effect series that is independent of the solvent and unrelated to surface properties. The specific-ion effects trends of standard partial molar volumes and normalised electrostrictive volumes examined in this work show a fundamental ion-specific series that is reproduced across the solvents, which is the Hofmeister series for anions and the reverse lyotropic series for cations, supporting the hypothesis. This outcome is important in demonstrating that ion specificity is observed at infinite dilution and demonstrates that the complexity observed in the manifestation of specific-ion effects in a very wide range of systems is due to perturbations of solvent, surfaces and concentration on the underlying fundamental series. This knowledge will guide a general understanding of specific

Effect of catecholamines and insulin on plasma volume and intravascular mass of albumin in man

DEFF Research Database (Denmark)

Hilsted, J; Christensen, N J; Larsen, S

1989-01-01

1. The effect of intravenous catecholamine infusions and of intravenous insulin on plasma volume and intravascular mass of albumin was investigated in healthy males. 2. Physiological doses of adrenaline (0.5 microgram/min and 3 microgram/min) increased peripheral venous packed cell volume...... significantly; intravenous noradrenaline at 0.5 microgram/min had no effect on packed cell volume, whereas packed cell volume increased significantly at 3 micrograms of noradrenaline/min. No significant change in packed cell volume was found during saline infusion. 3. During adrenaline infusion at 6 micrograms...... in packed cell volume, plasma volume, intravascular mass of albumin and transcapillary escape rate of albumin during hypoglycaemia may be explained by the combined actions of adrenaline and insulin....

Effect of electrolyte additives on performance of plasma electrolytic oxidation films formed on magnesium alloy AZ91D

International Nuclear Information System (INIS)

Duan, Hongping; Yan, Chuanwei; Wang, Fuhui

2007-01-01

Various plasma electrolytic oxidation (PEO) films were prepared on magnesium alloy AZ91D in a silicate bath with different additives such as phosphate, fluoride and borate. Effects of the additives on chemical composition and corrosion resistance of the PEO films were examined by means of scanning electron microscopy (SEM), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) in 3.5% NaCl solution. The results showed that the PEO films obtained in solutions with both borate and fluoride had better corrosion resistance. In order to understand the corrosion mechanism of PEO films on magnesium alloy AZ91D, electronic property of the magnesium electrode with PEO films was studied by Mott-Schottky approach in a solution containing borate and chloride. The results indicated that magnesium electrodes with and without PEO films all exhibited n-type semiconducting property. However, in comparison with the magnesium electrode treated in solutions containing phosphate or borate, the electrode treated in solutions containing both borate and fluoride (M-film) had lower donor concentration and much negative flat band potential; therefore, the M-film had lower reactivity and higher corrosion resistance

Blood and plasma volumes in normal west African dwarf sheep ...

African Journals Online (AJOL)

Blood and plasma volumes were determined using T-1824 in 36 normal adult West African Dwarf sheep. In the rams, dry ewes, pregnant ewes and lactating ewes, the mean values for the blood volume (ml/kg body weight) were 64.08 ± 6.11, 55.74 ± 9.31, 71.46 ± 6.46 and 147.12 ± 12.79 respectively, while the mean values ...

Oral rehydration therapy for preoperative fluid and electrolyte management.

Science.gov (United States)

Taniguchi, Hideki; Sasaki, Toshio; Fujita, Hisae

2011-01-01

Preoperative fluid and electrolyte management is usually performed by intravenous therapy. We investigated the safety and effectiveness of oral rehydration therapy (ORT) for preoperative fluid and electrolyte management of surgical patients. The study consisted of two studies, designed as a prospective observational study. In a pilot study, 20 surgical patients consumed 1000 mL of an oral rehydration solution (ORS) until 2 h before induction of general anesthesia. Parameters such as serum electrolyte concentrations, fractional excretion of sodium (FENa) as an index of renal blood flow, volume of esophageal-pharyngeal fluid and gastric fluid (EPGF), and patient satisfaction with ORT were assessed. In a follow-up study to assess the safety of ORT, 1078 surgical patients, who consumed ORS until 2 h before induction of general anesthesia, were assessed. In the pilot study, water, electrolytes, and carbohydrate were effectively and safely supplied by ORT. The FENa value was increased at 2 h following ORT. The volume of EPGF collected following the induction of anesthesia was 5.3±5.6 mL. In the follow-up study, a small amount of vomiting occurred in one patient, and no aspiration occurred in the patients. These results suggest that ORT is a safe and effective therapy for the preoperative fluid and electrolyte management of selected surgical patients.

Corrosion protection performance of single and dual Plasma Electrolytic Oxidation (PEO) coating for aerospace applications

International Nuclear Information System (INIS)

Madhan Kumar, A.; Kwon, Sun Hwan; Jung, Hwa Chul; Shin, Kwang Seon

2015-01-01

Plasma Electrolytic Oxidation (PEO) coatings are known to be one of the most appropriate method for corrosion protection of magnesium (Mg) alloy. The improvement of PEO coatings and the optimization of their surface aspects are of major importance. In this current work, the influence of dual PEO coating on strip-cast AZ31 Mg alloy substrate has been evaluated with the aim of improving the surface and corrosion protection aspects. For this purpose, AZ31 Mg substrates are subjected to single and dual PEO processing in silicate and phosphate electrolyte under similar condition. Scanning electron microscopy (SEM) analysis confirmed that the number of pores in PEO coating processed in silicate electrolyte is higher than others. X-ray diffraction analysis of PEO coatings showed that the surface coating is mainly comprised of Mg 2 SiO 4 , Mg 3 (PO 4 ) 2 and MgO with different quantity based on PEO processing. Compared with the AZ31 Mg, the corrosion potential (E corr ) of both type PEO coatings was positively shifted about 250–400 mV and the corrosion current density (i corr ) was lowered by 3-4 orders of magnitude as result of adequate corrosion protection to the Mg alloy in 3.5% NaCl solution. All of the observation obviously showed that the dual PEO coating provides better corrosion protection performance than their respective single due to its synergistic beneficial effect. - Highlights: • Influence of dual PEO coating on AZ31 Mg alloy substrate was evaluated. • XRD confirmed formation of thin MgO inner, Mg 3 (PO 4 ) 2 and Mg 2 SiO 4 outer layer. • SEM results showed uniform coating with no cracks and relatively less micro pores. • Micro hardness of dual PEO coatings is higher than single PEO coatings. • Dual coating provides superior corrosion performance due to its synergistic effect

Nanographene synthesized in triple-phase plasmas as a highly durable support of catalysts for polymer electrolyte fuel cells

Science.gov (United States)

Amano, Tomoki; Kondo, Hiroki; Takeda, Keigo; Ishikawa, Kenji; Hiramatsu, Mineo; Sekine, Makoto; Hori, Masaru

2018-04-01

Nanographene was synthesized in triple-phase plasmas comprising a gaseous phase, a gas-liquid boundary layer, and an in-liquid phase using a setup in which one electrode was placed in the gaseous phase while the other was immersed in the liquid phase. The triple-phase plasmas were generated using a pure alcohol, such as ethanol, 1-propanol, or 1-butanol, by applying a high voltage to a pair of electrodes made of copper or graphite. The nanographene synthesized using ethanol had high durability and thus could serve as a catalyst support in polymer electrolyte fuel cells (PEFCs). The PEFCs exhibited low degradation rates in the high-potential cycle test of a half-cell, as a result of which, a loss of only 10% was observed in the effective electrochemical surface area of Pt, even after 10,000 cycles.

Effect of Intravenous Small-Volume Hypertonic Sodium Bicarbonate, Sodium Chloride, and Glucose Solutions in Decreasing Plasma Potassium Concentration in Hyperkalemic Neonatal Calves with Diarrhea.

Science.gov (United States)

Trefz, F M; Constable, P D; Lorenz, I

2017-05-01

Hyperkalemia is a frequently observed electrolyte imbalance in dehydrated neonatal diarrheic calves that can result in skeletal muscle weakness and life-threatening cardiac conduction abnormalities and arrhythmias. Intravenous administration of a small-volume hypertonic NaHCO 3 solution is clinically more effective in decreasing the plasma potassium concentration (cK) in hyperkalemic diarrheic calves than hypertonic NaCl or glucose solutions. Twenty-two neonatal diarrheic calves with cK >5.8 mmol/L. Prospective randomized clinical trial. Calves randomly received either 8.4% NaHCO 3 (6.4 mL/kg BW; n = 7), 7.5% NaCl (5 mL/kg BW; n = 8), or 46.2% glucose (5 mL/kg BW; n = 7) IV over 5 minutes and were subsequently allowed to suckle 2 L of an electrolyte solution. Infusions with NaHCO 3 and NaCl provided an identical sodium load of 6.4 mmol/kg BW. Hypertonic NaHCO 3 infusions produced an immediate and sustained decrease in plasma cK. Hypertonic glucose infusions resulted in marked hyperglycemia and hyperinsulinemia, but cK remained unchanged for 20 minutes. Between 30 and 120 minutes after initiation of treatment, the most marked decrements in cK from baseline occurred in group NaHCO 3 , which were significantly (P < .05) larger during this period of time than in calves in group NaCl, but not group glucose. After 120 minutes, the mean decrease in cK from baseline was -26 ± 10%, -9 ± 8%, and -22 ± 6% in groups NaHCO 3 , NaCl, and glucose, respectively. Small-volume hypertonic NaHCO 3 infusions appear to have clinical advantages for the rapid resuscitation of hyperkalemic diarrheic calves, compared to hypertonic NaCl or glucose solutions. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Plasma uric acid and tumor volume are highly predictive of outcome in nasopharyngeal carcinoma patients receiving intensity modulated radiotherapy

International Nuclear Information System (INIS)

Lin, Hui; Lin, Huan-Xin; Ge, Nan; Wang, Hong-Zhi; Sun, Rui; Hu, Wei-Han

2013-01-01

The combined predictive value of plasma uric acid and primary tumor volume in nasopharyngeal carcinoma (NPC) patients receiving intensity modulated radiation therapy (IMRT) has not yet been determined. In this retrospective study, plasma uric acid level was measured after treatment in 130 histologically-proven NPC patients treated with IMRT. Tumor volume was calculated from treatment planning CT scans. Overall (OS), progression-free (PFS) and distant metastasis-free (DMFS) survival were compared using Kaplan-Meier analysis and the log rank test, and Cox multivariate and univariate regression models were created. Patients with a small tumor volume (<27 mL) had a significantly better DMFS, PFS and OS than patients with a large tumor volume. Patients with a high post-treatment plasma uric acid level (>301 μmol/L) had a better DMFS, PFS and OS than patients with a low post-treatment plasma uric acid level. Patients with a small tumor volume and high post-treatment plasma uric acid level had a favorable prognosis compared to patients with a large tumor volume and low post-treatment plasma uric acid level (7-year overall OS, 100% vs. 48.7%, P <0.001 and PFS, 100% vs. 69.5%, P <0.001). Post-treatment plasma uric acid level and pre-treatment tumor volume have predictive value for outcome in NPC patients receiving IMRT. NPC patients with a large tumor volume and low post-treatment plasma uric acid level may benefit from additional aggressive treatment after IMRT

Sweating, thirst perception and plasma electrolyte composition in ...

African Journals Online (AJOL)

Thirst is a perception, the subjective experience evoked by fluid deficits. Exercise induces sweating and subsequently electrolyte loss and thirst but there is little documented on post exercise thirst perception in women of varying body mass indices. 40 apparently healthy young women (19-25years) in the follicular phase of ...

Inductively coupled plasma emission spectroscopy. Part II: applications and fundamentals. Volume 2

International Nuclear Information System (INIS)

Boumans, P.W.J.M.

1987-01-01

This is the second part of the two-volume treatise by this well-known and respected author. This volume reviews applications of inductively coupled plasma atomic emission spectroscopy (ICP-AES), summarizes fundamental studies, and compares ICP-AES methods with other methods of analysis. The first six chapters are devoted to specific fields of application, including the following: metals and other industrial materials, geology, the environment, agriculture and food, biology and clinical analysis, and organic materials. The chapter on the analysis of organic materials also covers the special instrumental considerations required when organic solvents are introduced into an inductively coupled plasma. A chapter on the direct analysis of solids completes the first part of this volume. Each of the applications chapters begins with a summary of the types of samples that are encountered in that field, and the kinds of problems that an elemental analysis can help to solve. This is followed by a tutorial approach covering applicability, advantages, and limitations of the methods. The coverage is thorough, including sample handling, storage, and preparation, acid, and fusion dissolution, avoiding contamination, methods of preconcentration, the types of interferences that can be expected and ways to reduce them, and the types of ICP plasmas that are used. The second half of the volume covers fundamental studies of ICP-AES: basic processes of aerosol generation, plasma modeling and computer simulation, spectroscopic diagnostics, excitation mechanisms, and discharge characteristics. This section introduces the experimental and modeling methods that have been used to obtain fundamental information about ICPs

Cardiac adaptation to pregnancy in women with a history of preeclampsia and a subnormal plasma volume.

NARCIS (Netherlands)

Andrietti, S.; Kruse, A.J.; Bekkers, S.C.; Sep, S.; Spaanderman, M.E.A.; Peeters, L.L.

2008-01-01

In former preeclamptics, a subnormal plasma volume (LPV) predisposes to hemodynamic maladaptation to pregnancy. Here, we assessed the initial cardiovascular response to pregnancy in LPV (n = 20), in former preeclamptics with normal plasma volume (NPV) (n = 35) and in parous controls (CONTR) (n = 9)

Broadband frequency ECR ion source concepts with large resonant plasma volumes

International Nuclear Information System (INIS)

Alton, G.D.

1995-01-01

New techniques are proposed for enhancing the performances of ECR ion sources. The techniques are based on the use of high-power, variable-frequency, multiple-discrete-frequency, or broadband microwave radiation, derived from standard TWT technology, to effect large resonant ''volume'' ECR sources. The creation of a large ECR plasma ''volume'' permits coupling of more power into the plasma, resulting in the heating of a much larger electron population to higher energies, the effect of which is to produce higher charge state distributions and much higher intensities within a particular charge state than possible in present forms of the ECR ion source. If successful, these developments could significantly impact future accelerator designs and accelerator-based, heavy-ion-research programs by providing multiply-charged ion beams with the energies and intensities required for nuclear physics research from existing ECR ion sources. The methods described in this article can be used to retrofit any ECR ion source predicated on B-minimum plasma confinement techniques

Kinetics of aging of metastable solid electrolytes based on zirconium dioxide

International Nuclear Information System (INIS)

Vlasov, A.N.; Inozemtsev, M.V.

1985-01-01

Kinetics of aging of metastable solid electrolytes on the base of zirconium dioxide stabilized with 8-10 mol.%of yttrium, holmium, and scandium oxides has been studied within the 1200-1373 K temperature range. Kinetic equations describibg behaviour of electric conductivity of two-phase solid electrolytes within a wide temperature interval have been suggested. It has been established that at the initial stage of ageing in cubic solid solution two processes proceed independently of one another: growth of a number of new phase centres and of a volume of new phase centres. At large times growth of a number of new phase centres stops, and kinetics of electrolyte aging is defined only by the growth kinetics of a volume of new phase inclusions

Effects of cathode pulse at low frequency on the structure and composition of plasma electrolytic oxidation ceramic coatings

International Nuclear Information System (INIS)

Yao Zhongping; Xu Yongjun; Jiang Zhaohua; Wang Fuping

2009-01-01

The aim of this work is to investigate the effects of the cathode pulse under the low working frequency on the structure and the composition of the ceramic coatings on Ti-6Al-4V alloys by plasma electrolytic oxidation (PEO). Ceramic coatings were prepared on Ti alloy by pulsed bi-polar plasma electrolytic oxidation in NaAlO 2 solution. The phase composition, morphology, and element distribution in the coating were investigated by X-ray diffractometry, scanning electron microscopy, and energy distribution spectroscopy. The coating was mainly composed of a large amount of Al 2 TiO 5 and a little α-Al 2 O 3 and rutile TiO 2 . Increasing the cathode pulse, the amount of rutile TiO 2 was increased while the amount of Al 2 O 3 was decreased; and decreasing the cathode pulse, the amount of Al 2 O 3 was increased while the amount of rutile TiO 2 was decreased. The thickness of the coatings was increased and then decreased with the increase of the cathode pulse. The grain sizes of Al 2 TiO 5 were increased with the cathode current densities, but changed little with the cathode pulse width. The grain size of α-Al 2 O 3 was decreased with the decrease of the cathode pulse, while the grain size of TiO 2 was increased with the increase of the cathode pulse. The proper cathode pulse was helpful to reduce the roughness and to increase the density of the coatings.

Part 2: Limiting apparent molar volume of organic and inorganic 1:1 electrolytes in (water + ethylammonium nitrate) mixtures at 298 K - Thermodynamic approach using Bahe-Varela pseudo-lattice theory

International Nuclear Information System (INIS)

Bouguerra, Sabbah; Bou Malham, Ibrahim; Letellier, Pierre; Mayaffre, Alain; Turmine, Mireille

2008-01-01

Values of partial molar volumes at infinite dilution of 9 inorganic and 4 organic 1:1 electrolytes have been determined in (water + ethylammonium nitrate) (EAN) binary at 298.15 K throughout the composition scale. Our theoretical analysis shows that the values of partial molar volumes at infinite dilution of a solute in a binary are linked to those of the partial molar volumes of the components of mixed solvent. This applies to mixtures of molecular solvents as well as (water + ionic liquid) media. The use of the 'pseudo-lattice theory' of Bahe recently supplemented Varela can be used for calculations and to obtain information about the interactions between 1:1 electrolytes as solutes at infinite dilution and their concentrated saline environment. We show that the 'pseudo-lattice theory' allows accurate description of the behaviours of symmetrical tetraalkylammoniums bromide between the infinitely dilute state and concentrations higher than 2 mol . L -1

Corrosion behaviors and effects of corrosion products of plasma electrolytic oxidation coated AZ31 magnesium alloy under the salt spray corrosion test

Science.gov (United States)

Wang, Yan; Huang, Zhiquan; Yan, Qin; Liu, Chen; Liu, Peng; Zhang, Yi; Guo, Changhong; Jiang, Guirong; Shen, Dejiu

2016-08-01

The effects of corrosion products on corrosion behaviors of AZ31 magnesium alloy with a plasma electrolytic oxidation (PEO) coating were investigated under the salt spray corrosion test (SSCT). The surface morphology, cross-sectional microstructure, chemical and phase compositions of the PEO coating were determined using scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction analysis (XRD), respectively. Further, the corrosion process of the samples under the SSCT was examined in a non-aqueous electrolyte (methanol) using electrochemical impedance spectroscopy (EIS) coupled with equivalent circuit. The results show that the inner layer of the coating was destroyed firstly and the corrosion products have significant effects on the corrosion behaviors of the coating. The results above are discussed and an electrochemical corrosion model is proposed in the paper.

Surface modification by electrolytic plasma processing for high Nb-TiAl alloys

Science.gov (United States)

Gui, Wanyuan; Hao, Guojian; Liang, Yongfeng; Li, Feng; Liu, Xiao; Lin, Junpin

2016-12-01

Metal surface modification by electrolytic plasma processing (EPP) is an innovative treatment widely commonly applied to material processing and pretreatment process of coating and galvanization. EPP involves complex processes and a great deal of parameters, such as preset voltage, current, solution temperature and processing time. Several characterization methods are presented in this paper for evaluating the micro-structure surfaces of Ti45Al8Nb alloys: SEM, EDS, XRD and 3D topography. The results showed that the oxide scale and other contaminants on the surface of Ti45Al8Nb alloys can be effectively removed via EPP. The typical micro-crater structure of the surface of Ti45Al8Nb alloys were observed by 3D topography after EPP to find that the mean diameter of the surface structure and roughness value can be effectively controlled by altering the processing parameters. The mechanical properties of the surface according to nanomechanical probe testing exhibited slight decrease in microhardness and elastic modulus after EPP, but a dramatic increase in surface roughness, which is beneficial for further processing or coating.

A zwitterionic gel electrolyte for efficient solid-state supercapacitors

Science.gov (United States)

Peng, Xu; Liu, Huili; Yin, Qin; Wu, Junchi; Chen, Pengzuo; Zhang, Guangzhao; Liu, Guangming; Wu, Changzheng; Xie, Yi

2016-01-01

Gel electrolytes have attracted increasing attention for solid-state supercapacitors. An ideal gel electrolyte usually requires a combination of advantages of high ion migration rate, reasonable mechanical strength and robust water retention ability at the solid state for ensuring excellent work durability. Here we report a zwitterionic gel electrolyte that successfully brings the synergic advantages of robust water retention ability and ion migration channels, manifesting in superior electrochemical performance. When applying the zwitterionic gel electrolyte, our graphene-based solid-state supercapacitor reaches a volume capacitance of 300.8 F cm−3 at 0.8 A cm−3 with a rate capacity of only 14.9% capacitance loss as the current density increases from 0.8 to 20 A cm−3, representing the best value among the previously reported graphene-based solid-state supercapacitors, to the best of our knowledge. We anticipate that zwitterionic gel electrolyte may be developed as a gel electrolyte in solid-state supercapacitors. PMID:27225484

Electrolyte for stable cycling of high-energy lithium sulfur redox flow batteries

Science.gov (United States)

Xiao, Jie; Liu, Jun; Pan, Huilin; Henderson, Wesley A.

2018-04-24

A device comprising: a lithium sulfur redox flow battery comprising an electrolyte composition comprising: (i) a dissolved Li2Sx electroactive salt, wherein x.gtoreq.4; (ii) a solvent selected from dimethyl sulfoxide, tetrahydrofuran, or a mixture thereof; and (iii) a supporting salt at a concentration of at least 2 M, as measured by moles of supporting salt divided by the volume of the solvent without considering the volume change of the electrolyte after dissolving the supporting salt.

Kinetics of aging of metastable, zirconium-dioxide-based solid electrolytes

International Nuclear Information System (INIS)

Vlasov, A.N.; Inozemtsev, M.V.

1985-01-01

The kinetics of aging of zirconium-dioxide-based metastable solid oxide electrolytes stabilized with 8 to 10 mole % of yttrium, holmium, or scandium oxide were studied over the temperature range from 1200 to 1373 0 K. Kinetic equations were proposed which describe the conduction behavior of two-phase solid electrolytes in a wide time range. The processes were found to occur independently at the initial stage of aging in the cubic solution, viz., an increase in the number of nuclei of the new phase, and a growth in volume of nuclei of the new phase. After a long time the former process ceases, and the kinetics of aging of the electrolyte only are determined by the kinetics of volume growth of the inclusions of new phase. The time-dependent behavior of two-phase solid solutions is discussed theoretically and examined experimentally

A Suitable Polysulfide Electrolyte for CdSe Quantum Dot-Sensitized Solar Cells

Directory of Open Access Journals (Sweden)

H. K. Jun

2013-01-01

Full Text Available A polysulfide liquid electrolyte is developed for the application in CdSe quantum dot-sensitized solar cells (QDSSCs. A solvent consisting of ethanol and water in the ratio of 8 : 2 by volume has been found as the optimum solvent for preparing the liquid electrolytes. This solvent ratio appears to give higher cell efficiency compared to pure ethanol or water as a solvent. Na2S and S give rise to a good redox couple in the electrolyte for QDSSC operation, and the optimum concentrations required are 0.5 M and 0.1 M, respectively. Addition of guanidine thiocyanate (GuSCN to the electrolyte further enhances the performance. The QDSSC with CdSe sensitized electrode prepared using 7 cycles of successive ionic layer adsorption and reaction (SILAR produces an efficiency of 1.41% with a fill factor of 44% on using a polysulfide electrolyte of 0.5 M Na2S, 0.1 M S, and 0.05 M GuSCN in ethanol/water (8 : 2 by volume under the illumination of 100 mW/cm2 white light. Inclusion of small amount of TiO2 nanoparticles into the electrolyte helps to stabilize the polysulfide electrolyte and thereby improve the stability of the CdSe QDSSC. The CdSe QDs are also found to be stable in the optimized polysulfide liquid electrolyte.

Bioactivity and biocompatibility of hydroxyapatite-based bioceramic coatings on zirconium by plasma electrolytic oxidation

Energy Technology Data Exchange (ETDEWEB)

Aktuğ, Salim Levent, E-mail: saktug@gtu.edu.tr [The Department of Materials Science and Engineering, Gebze Technical University, Gebze, Kocaeli 41400 (Turkey); Durdu, Salih, E-mail: durdusalih@gmail.com [The Department of Industrial Engineering, Giresun University, Merkez, Giresun 28200 (Turkey); Yalçın, Emine, E-mail: emine.yalcin@giresun.edu.tr [The Department of Biology, Giresun University, Merkez, Giresun 28200 (Turkey); Çavuşoğlu, Kültigin, E-mail: kultigin.cavusoglu@giresun.edu.tr [The Department of Biology, Giresun University, Merkez, Giresun 28200 (Turkey); Usta, Metin, E-mail: ustam@gtu.edu.tr [The Department of Materials Science and Engineering, Gebze Technical University, Gebze, Kocaeli 41400 (Turkey); Materials Institute, Marmara Research Center, TUBITAK, Gebze, Kocaeli 41470 (Turkey)

2017-02-01

In the present work, hydroxyapatite (HAP)-based plasma electrolytic oxide (PEO) coatings were produced on zirconium at different current densities in a solution containing calcium acetate and β-calcium glycerophosphate by a single step. The phase structure, surface morphology, functional groups, thickness and roughness of the coatings were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), eddy current method and surface profilometer, respectively. The phases of cubic-zirconia, calcium zirconate and HAP were detected by XRD. The amount of HAP and calcium zirconate increased with increasing current density. The surface of the coatings was very porous and rough. Moreover, bioactivity and biocompatibility of the coatings were analyzed in vitro immersion simulated body fluid (SBF) and MTT (3-(4,5-dimethyl thiazol-2yl)-2,5-diphenyl tetrazolium bromide) assay, hemolysis assay and bacterial formation. The apatite-forming ability of the coatings was evaluated after immersion in SBF up to 28 days. After immersion, the bioactivity of HAP-based coatings on zirconium was greater than the ones of uncoated zirconium and zirconium oxide-based surface. The bioactivity of PEO surface on zirconium was significantly improved under SBF conditions. The bacterial adhesion of the coatings decreased with increasing current density. The bacterial adhesion of the coating produced at 0.370 A/cm{sup 2} was minimum compared to uncoated zirconium coated at 0.260 and 0.292 A/cm{sup 2}. The hemocompatibility of HAP-based surfaces was improved by PEO. The cell attachment and proliferation of the PEO coatings were better than the one of uncoated zirconium according to MTT assay results. - Highlights: • Hydroxyapatite was formed on zirconium at different current densities by single-step plasma electrolytic oxidation. • The amount of hydroxyapatite and calcium-based phases increased with

Electrolyte for stable cycling of high-energy lithium sulfur redox flow batteries

Energy Technology Data Exchange (ETDEWEB)

Xiao, Jie; Liu, Jun; Pan, Huilin; Henderson, Wesley A.

2018-04-24

A device comprising: a lithium sulfur redox flow battery comprising an electrolyte composition comprising: (i) a dissolved Li₂S_x electroactive salt, wherein x.gtoreq.4; (ii) a solvent selected from dimethyl sulfoxide, tetrahydrofuran, or a mixture thereof; and (iii) a supporting salt at a concentration of at least 2 M, as measured by moles of supporting salt divided by the volume of the solvent without considering the volume change of the electrolyte after dissolving the supporting salt.

The effect of an angiotensin-converting enzyme inhibitor on water and electrolyte balance in water-restricted sheep

Directory of Open Access Journals (Sweden)

R.A. Meintjies

1999-07-01

Full Text Available The importance of angiotensin II in the regulation of water and electrolyte balance in sheep is questionable. In this trial the effects of an angiotensin-converting enzyme (ACE inhibitor were quantified in sheep on restricted water intake. Comparing the phase of water restriction only with that of water restriction plus ACE inhibition, significant increases were observed during the latter phase in urine volume, sodium and potassium excretion via the urine, sodium concentration in the plasma and osmolar clearance. Urine osmolarity decreased with inhibition of angiotensin II formation while variables such as water, sodium and potassium loss via the faeces were unaffected. Most of the renal effects of ACE inhibition, except the increase in urinary potassium excretion, were explicable in terms of the established functions of angiotensin II. Furthermore, results of this trial indicate that angiotensin II has no significant effect on the intestine in regulating water and electrolyte excretion via the faeces.

Sparingly Solvating Electrolytes for High Energy Density Lithium-Sulfur Batteries

Energy Technology Data Exchange (ETDEWEB)

Cheng, Lei; Curtiss, Larry A.; Zavadil, Kevin R.; Gewirth, Andrew A.; Shao, Yuyan; Gallagher, Kevin

2016-07-11

Moving to lighter and less expensive battery chemistries compared to lithium-ion requires the control of energy storage mechanisms based on chemical transformations rather than intercalation. Lithium sulfur (Li/S) has tremendous theoretical specific energy, but contemporary approaches to control this solution-mediated, precipitation-dissolution chemistry requires using large excesses of electrolyte to fully solubilize the polysulfide intermediate. Achieving reversible electrochemistry under lean electrolyte operation is the only path for Li/S to move beyond niche applications to potentially transformational performance. An emerging topic for Li/S research is the use of sparingly solvating electrolytes and the creation of design rules for discovering new electrolyte systems that fundamentally decouple electrolyte volume from reaction mechanism. This perspective presents an outlook for sparingly solvating electrolytes as the key path forward for longer-lived, high-energy density Li/S batteries including an overview of this promising new concept and some strategies for accomplishing it.

Plasma volume changes during hypoglycaemia: the effect of arterial blood sampling

DEFF Research Database (Denmark)

Hilsted, J; Bendtsen, F; Christensen, N J

1990-01-01

To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... hypoglycaemia. The magnitude of the changes in arterial and venous blood were not significantly different. These results indicate that the above changes in blood volume and composition are whole-body phenomena: furthermore, the major part of the changes are likely to occur in tissues other than upper extremity...

The formation of tungsten doped Al_2O_3/ZnO coatings on aluminum by plasma electrolytic oxidation and their application in photocatalysis

International Nuclear Information System (INIS)

Stojadinović, Stevan; Vasilić, Rastko; Radić, Nenad; Tadić, Nenad; Stefanov, Plamen; Grbić, Boško

2016-01-01

Highlights: • Tungsten doped Al_2O_3/ZnO coatings are formed by plasma electrolytic oxidation (PEO). • Coatings are mainly composed of alpha alumina, ZnO and metallic tungsten. • Photocatalytic activity of doped Al_2O_3/ZnO coatings is higher than of undoped ones. • The increase of photoluminescence corresponds to decrease of photocatalytic activity. • Tungsten acts as a charge trap to reduce the recombination rate of electron/hole pairs. - Abstract: Tungsten doped Al_2O_3/ZnO coatings are formed by plasma electrolytic oxidation of aluminum substrate in supporting electrolyte (0.1 M boric acid + 0.05 M borax + 2 g/L ZnO) with addition of different concentrations of Na_2WO_4·2H_2O. The morphology, crystal structure, chemical composition, and light absorption characteristics of formed surface coatings are investigated. The X-ray diffraction and X-ray photoelectron spectroscopy results indicate that formed surface coatings consist of alpha and gamma phase of Al_2O_3, ZnO, metallic tungsten and WO_3. Obtained results showed that incorporated tungsten does not have any influence on the absorption spectra of Al_2O_3/ZnO coatings, which showed invariable band edge at about 385 nm. The photocatalytic activity of undoped and tungsten doped Al_2O_3/ZnO coatings is estimated by the photodegradation of methyl orange. The photocatalytic activity of tungsten doped Al_2O_3/ZnO coatings is higher thanof undoped Al_2O_3/ZnO coatings; the best photocatalytic activity is ascribed to coatings formed in supporting electrolyte with addition of 0.3 g/L Na_2WO_4·2H_2O. Tungsten in Al_2O_3/ZnO coatings acts as a charge trap, thus reducing the recombination rate of photogenerated electron-hole pairs. The results of PL measurements are in agreement with photocatalytic activity. Declining PL intensity corresponds to increasing photocatalytic activity of the coatings, indicating slower recombination of electron-hole pairs.

Formation of Ca/P ceramic coatings by Plasma Electrolytic Oxidation (PEO) on Ti6Al4V ELI alloy

Science.gov (United States)

Rodriguez-Jaimes, Y.; Naranjo, D. I.; Blanco, S.; García-Vergara, S. J.

2017-12-01

The formation of PEO ceramic coatings on Ti6Al4V ELI alloy was investigated using a phosphate/calcium containing electrolyte at 300 and 400V at 310K for different times. The Plasma Electrolytic Oxidation (PEO) coated specimens were then heat treated at 873 and 1073K for 2 hours. Scanning electron microscopy, Energy Dispersive X-Ray Spectroscopy (EDS) and X-ray diffraction analysis were used to study the composition and the morphology of the ceramic coatings. The corrosion behaviour of the coatings was studied by Electrochemical Impedance Spectroscopy (EIS) in Simulated Body Fluid (SBF). The PEO-treated specimens primarily revealed a porous structure with thickness between 4 and 12μm, according to the voltage and process time used. The coatings are mainly composed of hydroxyapatite; however, as the voltage and anodizing time increase, the Ca/P ratio decreases. Generally, the corrosion resistance of the alloy was improved by the PEO-treated coatings, although the specimens treated at 1073K showed the presence of cracks that reduced the protective effect of the coatings.

Deposition of waste kaolin in aluminum alloy by electrolytic plasma technique

International Nuclear Information System (INIS)

Palinkas, Fabiola Bergamasco da Silva Marcondes; Antunes, Maria Lucia Pereira; Cruz, Nilson Cristino; Rangel, Elidiane Cipriano; Souza, Jose Antonio da Silva

2016-01-01

Full text: Kaolin is a widely explored mineral for various industrial purposes and its processing generates up to 90% of waste, corresponding to 500 thousand tons annually. The Deposition of Kaolin residue on aluminum alloys by electrolytic plasma has objective of a valorization of the residue. It was evaluated the mineralogical composition by X-ray diffraction (XRD), using PANalytical diffractometer X'Pert Pro. The scanning electron microscopy (SEM) and the spectrometry of dispersive of energy (EDS) evaluated the morphology and elementary chemical composition by microscope scanning electron JEOL JSM-6010LA. The Infrared Spectroscopy (FTIR) has used a Spectrometer the Perkin-Elmer 1760X FT-IR with spectral range 4000-400 cm -1 . XRD results indicate peaks of kaolinite as the main constituent. The morphology of the particles correspond to pseudo-hexagonal lamellar crystals characteristic of kaolinite, analysis by EDS allows to identify the composition of the particles as Al and Si. The samples were deposited at concentrations of 5, 10 and 15 mg of the residue and each concentration were considered deposition times of 5, 10 and 15 minutes. Tests evaluate the films as the wettability, chemical composition, morphology, mechanical strength and corrosion resistance. Results indicate the presence of kaolinite, alumina and mullite in the obtained coatings. (author)

Analyses of quenching process during turn-off of plasma electrolytic carburizing on carbon steel

International Nuclear Information System (INIS)

Wu, Jie; Liu, Run; Xue, Wenbin; Wang, Bin; Jin, Xiaoyue; Du, Jiancheng

2014-01-01

Highlights: • Cooling rate of carburized steel at the end of PEC treatment is measured. • The quench hardening in the fast or slow turn-off mode hardly takes place. • Decrease of the surface roughness during slow turn-off process is found. • A slow turn-off mode is recommended to replace the conventional turn-off mode. - Abstract: Plasma electrolytic carburizing (PEC) under different turn-off modes was employed to fabricate a hardening layer on carbon steel in glycerol solution without stirring at 380 V for 3 min. The quenching process in fast turn-off mode or slow turn-off mode of power supply was discussed. The temperature in the interior of steel and electron temperature in plasma discharge envelope during the quenching process were evaluated. It was found that the cooling rates of PEC samples in both turn-off modes were below 20 °C/s, because the vapor film boiling around the steel sample reduced the cooling rate greatly in terms of Leidenfrost effect. Thus the quench hardening hardly took place, though the slow turn-off mode slightly decreased the surface roughness of PEC steel. At the end of PEC treatment, the fast turn-off mode used widely at present cannot enhance the surface hardness by quench hardening, and the slow turn-off mode was recommended in order to protect the electronic devices against a large current surge

The McMillan-Mayer framework and the theory of electrolyte solutions

DEFF Research Database (Denmark)

Breil, Martin Peter; Mollerup, Jørgen

2006-01-01

In electrolyte thermodynamics one often speaks of two thermodynamic frameworks; the Lewis-Randall framework (characterised by temperature, pressure. and mole numbers) and the McMillan-Mayer framework (characterised by temperature, total volume, solute mole numbers, and solvent chemical potential......). However, there is only one framework in thermodynamics; the apparent difference between the two 'frameworks' is, in electrolyte thermodynamics, due to the change in the pressure caused by the charging process at constant volume and solvent chemical potential. The so-called McMillan-Mayer framework is set...... in the context of the classical thermodynamics and the use of it is examplified by the Debye-Huckel theory. The so-called McMillan-Mayer framework is superfluous when the thermodynamics of the electrolyte solutions is described by the Helmholtz energy functions. (c) 2006 Elsevier B.V. All rights reserved....

Preoperative fluid and electrolyte management with oral rehydration therapy.

Science.gov (United States)

Taniguchi, Hideki; Sasaki, Toshio; Fujita, Hisae; Takamori, Mina; Kawasaki, Rieko; Momiyama, Yukinori; Takano, Osami; Shibata, Toshinari; Goto, Takahisa

2009-01-01

We hypothesized that oral rehydration therapy using an oral rehydration solution may be effective for preoperative fluid and electrolyte management in surgical patients before the induction of general anesthesia, and we investigated the safety and effectiveness of oral rehydration therapy as compared with intravenous therapy. Fifty female patients who underwent breast surgery were randomly allocated to two groups. Before entry to the operation room and the induction of general anesthesia, 25 patients drank 1000 ml of an oral rehydration solution ("oral group") and 25 patients were infused with 1000 ml of an intravenous electrolyte solution ("intravenous group"). Parameters such as electrolyte concentrations in serum and urine, urine volume, vital signs, vomiting and aspiration, volumes of esophageal-pharyngeal fluid and gastric fluid (EPGF), and patient satisfaction with the therapy (as surveyed by a questionnaire) were assessed. After treatment, the serum sodium concentration and the hematocrit value, which both declined within the normal limits, were significantly higher in the oral group than in the intravenous group (sodium, 140.8 +/- 2.9 mEq x l(-1) in the oral group and 138.7 +/- 1.9 mEq x l(-1) in the intravenous group; P = 0.005; hematocrit, 39.03 +/- 4.16% in the oral group and 36.15 +/- 3.41% in the intravenous group; P = 0.01). No significant difference was observed in serum glucose values. Urine volume was significantly larger in the oral group (864.9 +/- 211.5 ml) than in the intravenous group (561.5 +/- 216.0 ml; P rehydration therapy, as judged by factors such as "feeling of hunger", "occurrence of dry mouth", and "less restriction in physical activity". The volume of EPGF collected following the induction of anesthesia was significantly smaller in the oral group than in the intravenous group (6.03 +/- 9.14 ml in the oral group and 21.76 +/- 30.56 ml in the intravenous group; P rehydration therapy with an oral rehydration solution before surgery is

Effectiveness of carnosine on disturbed electrolytes homeostasis ...

African Journals Online (AJOL)

We aimed to assess the effect of well known antioxidant carnosine on disturbed plasma and intraerythrocytes electrolytes and Na+-K+-ATPase activity by cisplatin. 24 male albino Wistar rats were selected and divided into 4 groups: Group I = untreated control; Group II = cisplatin control (received cisplatin at a dose of 3 mg/ ...

Surface modification of steels by electrical discharge treatment in electrolyte

International Nuclear Information System (INIS)

Krastev, D.; Paunov, V.; Yordanov, B.; Lazarova, V.

2013-01-01

Full text: In this work are discussed some experimental data about the influence of applied electrical discharge treatment in electrolyte on the surface structure of steels. The electrical discharge treatment of steel surface in electrolyte gives a modified structure with specific combination of characteristics in result of nonequilibrium transformations. The modification goes by a high energy thermal process in a very small volume on the metallic surface involving melting, vaporisation, activation and alloying in electrical discharges, and after that cooling of this surface with high rate in the electrolyte. The surface layers obtain a different structure in comparison with the metal matrix and are with higher hardness, wear resistance and corrosion resistance. key words: surface modification, electrical discharge treatment in electrolyte, steels

Predicted Hematologic and Plasma Volume Responses Following Rapid Ascent to Progressive Altitudes

Science.gov (United States)

2014-06-01

Detection of unethical and illegal manipulation of erythrocyte volume by following changes in hemoglobin concentration ([Hb]) in elite athletes is a...tolerance to environmental extremes [2,3] and such manipulation often results in acute plasma volume (PV) loss and elevated hemoglobin concentrations [3...bodies to detect "unfair practices" in athletes seeking to gain an edge in their performance through illegal manipulation of their erythrocyte

Polymer Electrolytes

Science.gov (United States)

Hallinan, Daniel T.; Balsara, Nitash P.

2013-07-01

This review article covers applications in which polymer electrolytes are used: lithium batteries, fuel cells, and water desalination. The ideas of electrochemical potential, salt activity, and ion transport are presented in the context of these applications. Potential is defined, and we show how a cell potential measurement can be used to ascertain salt activity. The transport parameters needed to fully specify a binary electrolyte (salt + solvent) are presented. We define five fundamentally different types of homogeneous electrolytes: type I (classical liquid electrolytes), type II (gel electrolytes), type III (dry polymer electrolytes), type IV (dry single-ion-conducting polymer electrolytes), and type V (solvated single-ion-conducting polymer electrolytes). Typical values of transport parameters are provided for all types of electrolytes. Comparison among the values provides insight into the transport mechanisms occurring in polymer electrolytes. It is desirable to decouple the mechanical properties of polymer electrolyte membranes from the ionic conductivity. One way to accomplish this is through the development of microphase-separated polymers, wherein one of the microphases conducts ions while the other enhances the mechanical rigidity of the heterogeneous polymer electrolyte. We cover all three types of conducting polymer electrolyte phases (types III, IV, and V). We present a simple framework that relates the transport parameters of heterogeneous electrolytes to homogeneous analogs. We conclude by discussing electrochemical stability of electrolytes and the effects of water contamination because of their relevance to applications such as lithium ion batteries.

Selection and development of an easy to process electrolyte for decontamination by electropolishing

International Nuclear Information System (INIS)

Steringer, A.; Moser, T.

1989-01-01

Three different organic electrolytes: formic acid (E 1), oxalic acid (E 2) and acetylacetone (E 3) using potassium bromide (KBr) as the auxiliary electrolyte, were tested in the laboratory for electrochemically dissolving steel and stainless steel. The best results in the preliminary test series were attained with acetylacetone. It ranks among the first for current efficiency, with the produced acetylacetonates having the lowest solubility and thus they settle out of the solution in the form of coarse crystalline products. Tests were made on radioactive reactor components using acetylacetone in a 400 A test facility, to verify and optimize the decontamination factors, the electrolyte service life and the produced waste volume, as well as the respective process parameters. The surface activity of the components ranged from 2 to 10 Bq/cm 2 , and a decontamination factor of 30 was attained. The obtained specific waste volume is 1.1 litre/m 2 of decontaminated surface. A gamma-spectrometric evaluation revealed that the activity in the settled-out metallic acetylacetonate is five times higher than that in the electrolyte. It is only necessary to refill the spent acetylacetonate which makes it then possible to continue to use the electrolyte solution almost unrestrictedly

Evolution processes of the corrosion behavior and structural characteristics of plasma electrolytic oxidation coatings on AZ31 magnesium alloy

Science.gov (United States)

Chen, Dong; Wang, Ruiqiang; Huang, Zhiquan; Wu, Yekang; Zhang, Yi; Wu, Guorui; Li, Dalong; Guo, Changhong; Jiang, Guirong; Yu, Shengxue; Shen, Dejiu; Nash, Philip

2018-03-01

Evolution processes of the corrosion behavior and structural characteristics of the plasma electrolytic oxidation (PEO) coated AZ31 magnesium alloy were investigated by using scanning electron microscope (SEM) equipped with energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), potentio-dynamic polarization curves and electrochemical impedance spectroscopy (EIS) measurements. Detached coating samples were fabricated by an electrochemical method and more details of the internal micro-structure of coatings were clearly observed on the fractured cross-section morphologies of the samples compared to general polished cross-section morphologies. Evolution mechanisms of the coating corrosion behavior in relation to the evolution of micro-structural characteristics were discussed in detail.

REMOVAL OF COPPER ELECTROLYTE CONTAMINANTS BY ADSORPTION

Directory of Open Access Journals (Sweden)

B Gabai

1997-09-01

Full Text Available Abstract - Selective adsorbents have become frequently used in industrial processes. Recent studies have shown the possibility of using adsorption to separate copper refinery electrolyte contaminants, with better results than those obtained with conventional techniques. During copper electrorefinning, many impurities may be found as dissolved metals present in the anode slime which forms on the electrode surface, accumulated in the electrolyte or incorporated into the refined copper on the cathode by deposition. In this study, synthetic zeolites, chelating resins and activated carbons were tested as adsorbents to select the best adsorbent performance, as well as the best operating temperature for the process. The experimental method applied was the finite bath, which consists in bringing the adsorbent into contact with a finite volume of electrolyte while controlling the temperature. The concentration of metals in the liquid phase was continuously monitored by atomic absorption spectrophotometry (AAS

Effects of concentration of Ag nanoparticles on surface structure and in vitro biological responses of oxide layer on pure titanium via plasma electrolytic oxidation

Energy Technology Data Exchange (ETDEWEB)

Shin, Ki Ryong; Kim, Yeon Sung; Kim, Gye Won [Department of Materials Science and Engineering, Hanyang University, Ansan 425-791 (Korea, Republic of); Yang, Hae Woong [School of Materials Science and Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Ko, Young Gun, E-mail: younggun@ynu.ac.kr [School of Materials Science and Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Shin, Dong Hyuk, E-mail: dhshin@hanyang.ac.kr [Department of Materials Science and Engineering, Hanyang University, Ansan 425-791 (Korea, Republic of)

2015-08-30

Highlights: • Ag nanoparticles were embedded into the oxide surface without any compositional changes. • Oxide layer from the electrolyte with 0.1 g/l Ag nanoparticles could disinfect all bacteria. • With increasing Ag nanoparticles, bone-forming ability and cell proliferation rate decrease. - Abstract: This study was to investigate how Ag nanoparticles with various concentrations affect the surface structure and in vitro biological properties of oxide layers on the pure titanium produced by a plasma electrolytic oxidation (PEO) process. For this aim, PEO processes were carried out at an AC current density of 100 mA/cm{sup 2} for 300 s in potassium pyrophosphate (K{sub 4}P{sub 2}O{sub 7}) electrolytes containing 0, 0.1, 0.3 and 0.5 g/l Ag nanoparticles. Structural investigations using scanning electron microscopy evidenced that the oxide layers showed the successful incorporation of Ag nanoparticles, and the topographical deformation of the porous surface was found when the concentration of Ag nanoparticles was more than 0.1 g/l. Based on the anti-bacterial activity of all oxide layers, the Ag nanoparticles uniformly spread were of considerable importance in triggering the disinfection of E. coli bacteria. The bone forming abilities and cell (MC3T3-E1) proliferation rates of oxide layers produced in electrolytes containing 0 and 0.1 g/l Ag nanoparticles were higher than those containing 0.3 and 0.5 g/l Ag nanoparticles. Consequently, the oxide layer on pure titanium via PEO process in the electrolyte with 0.1 g/l Ag nanoparticles exhibited better the bioactivity accompanying the anti-bacterial activity.

Impact of diuretic treatment and sodium intake on plasma volume in patients with compensated systolic heart failure

DEFF Research Database (Denmark)

Bonfils, Peter K; Damgaard, Morten; Taskiran, Mustafa

2010-01-01

AIMS: In patients with heart failure (HF), the use of diuretics may be a double-edged sword that can alleviate symptoms of congestion, but also result in over-diuresis and intravascular volume depletion. The purpose of the present study was to examine plasma volume (PV) in HF patients receiving...... difference in PV between patients with HF and control subjects (37.3 +/- 6.0 and 40.2 +/- 5.8 mL/kg, respectively, P = 0.092) with a significant tendency towards a contraction of PV with increasing use of diuretics (P = 0.031). There was no difference in extracellular volume between patients with HF...... and control subjects (P = 0.844). NT-proBNP plasma concentrations had no correlation to either sodium excretion (P = 0.193) or PV (P = 0.471) in patients with HF. CONCLUSION: Plasma volume in patients with HF was within normal limits, but patients treated with high doses of loop-diuretics tended to have...

Immunoglobulin G levels during collection of large volume plasma for fractionation.

Science.gov (United States)

Burkhardt, Thomas; Rothe, Remo; Moog, Rainer

2017-06-01

There is a need of comprehensive work dealing with the quality of plasma for fractionation with respect to the IgG content as today most plasma derivates are used to treat patients with immunodeficiencies and autoimmune disorders. Therefore, a prospective study was carried out to analyse IgG levels before plasmapheresis and every 200ml collected plasma. Fifty-four experienced plasmapheresis donors were recruited for subsequent 850ml plasmapheresis using the Aurora Plasmapheresis System. Donorś peripheral blood counts were analysed before and after plasmapheresis using an electronic counter. Total protein, IgG and citrate were measured turbidometrically before, during and after apheresis as well as in the plasma product. Furthermore, platelets, red and white blood cells were analysed as parameters of product quality. An average of 2751±247ml blood was processed in 47±6min. The collected plasma volume was 850±1mL and citrate consumption was 177±15mL. A continuous drop of donors' IgG level was observed during plasmapheresis. The drop was 13% of the IgG baseline value at 800mL collected plasma. Total protein, IgG and cell counts of the plasma product met current guidelines of plasma for fractionation. Donors' IgG levels during apheresis showed a steady decrease without compromising the quality of plasma product. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of (NaPO3)6 concentrations on corrosion resistance of plasma electrolytic oxidation coatings formed on AZ91D magnesium alloy

International Nuclear Information System (INIS)

Luo Haihe; Cai Qizhou; Wei Bokang; Yu Bo; Li Dingjun; He Jian; Liu Ze

2008-01-01

Different plasma electrolytic oxidation (PEO) coatings were prepared on AZ91D magnesium alloy in electrolytes containing various concentrations of (NaPO 3 ) 6 . The morphologies, chemical compositions and corrosion resistance of the PEO coatings were characterized by environmental scanning electron microscopy (ESEM), X-ray diffractometer (XRD), energy dispersive analysis of X-rays (EDAX), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) test. The results showed that the PEO coatings were mainly composed of MgO, Mg 2 SiO 4 , MgAl 2 O 4 and amorphous compounds. As the (NaPO 3 ) 6 concentrations increased from 0 to 10 g/l, the thickness and surface roughness of the coatings approximately linearly increased; the MgO and Mg 2 SiO 4 phase increased within the concentration range of 0-3 and 0-5 g/l, and then decreased within the range of 3-10 and 5-10 g/l, respectively, while the MgAl 2 O 4 phase gradually decreased. Moreover, the corrosion resistance of the coatings increased within the range of 0-5 g/l and then decreased within the range of 5-10 g/l. The best corrosion resistance coating was obtained in electrolyte containing 5 g/l (NaPO 3 ) 6 , it had the most compact microstructure. Besides, a reasonable equivalent circuit was established, and the fitting results were consistent with the results of the EIS test

Altitude Acclimatization and Blood Volume: Effects of Exogenous Erythrocyte Volume Expansion

National Research Council Canada - National Science Library

Sawka, M

1996-01-01

...: (a) altitude acclimatization effects on erythrocyte volume and plasma volume; (b) if exogenous erythrocyte volume expansion alters subsequent erythrocyte volume and plasma volume adaptations; (c...

Effects of Beer, Non-Alcoholic Beer and Water Consumption before Exercise on Fluid and Electrolyte Homeostasis in Athletes.

Science.gov (United States)

Castro-Sepulveda, Mauricio; Johannsen, Neil; Astudillo, Sebastián; Jorquera, Carlos; Álvarez, Cristian; Zbinden-Foncea, Hermann; Ramírez-Campillo, Rodrigo

2016-06-07

Fluid and electrolyte status have a significant impact on physical performance and health. Pre-exercise recommendations cite the possibility of consuming beverages with high amounts of sodium. In this sense, non-alcoholic beer can be considered an effective pre-exercise hydration beverage. This double-blind, randomized study aimed to compare the effect of beer, non-alcoholic beer and water consumption before exercise on fluid and electrolyte homeostasis. Seven male soccer players performed 45 min of treadmill running at 65% of the maximal heart rate, 45 min after ingesting 0.7 L of water (W), beer (AB) or non-alcoholic beer (NAB). Body mass, plasma Na⁺ and K⁺ concentrations and urine specific gravity (USG) were assessed before fluid consumption and after exercise. After exercise, body mass decreased (p beer before exercise could help maintain electrolyte homeostasis during exercise. Alcoholic beer intake reduced plasma Na⁺ and increased plasma K⁺ during exercise, which may negatively affect health and physical performance, and finally, the consumption of water before exercise could induce decreases of Na⁺ in plasma during exercise.

Multiple Electrolyte and Metabolic Emergencies in a Single Patient

Directory of Open Access Journals (Sweden)

Caprice Cadacio

2017-01-01

Full Text Available While some electrolyte disturbances are immediately life-threatening and must be emergently treated, others may be delayed without immediate adverse consequences. We discuss a patient with alcoholism and diabetes mellitus type 2 who presented with volume depletion and multiple life-threatening electrolyte and metabolic derangements including severe hyponatremia (serum sodium concentration [SNa] 107 mEq/L, hypophosphatemia (“undetectable,” <1.0 mg/dL, and hypokalemia (2.2 mEq/L, moderate diabetic ketoacidosis ([DKA], pH 7.21, serum anion gap [SAG] 37 and hypocalcemia (ionized calcium 4.0 mg/dL, mild hypomagnesemia (1.6 mg/dL, and electrocardiogram with prolonged QTc. Following two liters of normal saline and associated increase in SNa by 4 mEq/L and serum osmolality by 2.4 mosm/Kg, renal service was consulted. We were challenged with minimizing the correction of SNa (or effective serum osmolality to avoid the osmotic demyelinating syndrome while replacing volume, potassium, phosphorus, calcium, and magnesium and concurrently treating DKA. Our management plan was further complicated by an episode of significant aquaresis. A stepwise approach was strategized to prioritize and correct all disturbances with considerations that the treatment of one condition could affect or directly worsen another. The current case demonstrates that a thorough understanding of electrolyte physiology is required in managing complex electrolyte disturbances to avoid disastrous outcomes.

Physiological adaptation of maternal plasma volume during pregnancy: a systematic review and meta-analysis.

Science.gov (United States)

de Haas, S; Ghossein-Doha, C; van Kuijk, S M J; van Drongelen, J; Spaanderman, M E A

2017-02-01

To describe the physiological pattern of gestational plasma volume adjustments in normal singleton pregnancy and compare this with the pattern in pregnancies complicated by pregnancy-induced hypertension, pre-eclampsia or fetal growth restriction. We performed a meta-analysis of the current literature on plasma volume adjustments during physiological and complicated pregnancies. Literature was retrieved from PubMed (NCBI) and EMBASE (Ovid) databases. Included studies reported both reference plasma volume measurements (non-pregnant, prepregnancy or postpartum) and measurements obtained during predetermined gestational ages. Mean differences bet ween the reference and pregnancy plasma volume measurements were calculated for predefined intervals of gestational age using a random-effects model described by DerSimonian and Laird. Thirty studies were included in the meta-analysis with publication dates ranging from 1934 to 2007. Plasma volume increased in the first weeks of pregnancy, with the steepest increase occurring during the second trimester. Plasma volume continued to increase in the third trimester with a pooled maximum increase of 1.13 L (95% CI, 1.07-1.19 L), an increase of 45.6% (95% CI, 43.0-48.1%) in physiological pregnancies compared with the reference value. The plasma volume expansion in gestational hypertensive and growth-restricted pregnancies was 0.80 L (95% CI, 0.59-1.02 L), an increase of 32.3% (95% CI, 23.6-41.1%) in the third trimester, a smaller increase than in physiological pregnancies (P embarazo: una revisi\\xF3n sistemática y metaanálisis RESUMEN OBJETIVO: Describir el patrón fisiológico de los cambios en el volumen del plasma gestacional en embarazos normales con feto único y compararlo con el patrón en los embarazos complicados por hipertensión gestacional, preeclampsia o restricción del crecimiento fetal. MÉTODOS: Se realizó un metaanálisis de la literatura actual sobre los cambios en el volumen de plasma durante

Plasma volume, intravascular albumin and its transcapillary escape rate in patients with extensive skin disease

DEFF Research Database (Denmark)

Parving, H H; Worm, A M; Rossing, N

1976-01-01

Plasma volume and plasma concentration and transcapillary escape rate of albumin (TER alb), i.e. the fraction of intravascular mass of albumin that passes to the extravascular space per unit time, were determined using 125I-labelled human albumin in eight patients with extensive skin disease....... Plasma volume and plasma albumin concentration were reduced (P less than 0-05). Thus the intravascular albumin mass was moderately decreased to an average of 0-55 +/- 0-06 (s.d.) g/cm height compared with a normal mean value of 0-77 +/- 0-07 (s.d.) g/cm. This 29% decrease is statistically significant (P...... less than 0-001). The transcapillary escape rate of albumin (TER alb) was significantly elevated, mean 8-6 +/- 1-1 (s.d.) % X h-1, as compared to normal subjects, mean 5-6 +/- 1-1 (s.d.) % X h-1, (+54%, P less than 0-001). The same patients were studied again after a 1-week treatment with prednisone...

Internal-reference solid-electrolyte oxygen sensor

International Nuclear Information System (INIS)

Haaland, D.M.

1977-01-01

A new solid-electrolyte oxygen sensor has been developed that eliminates the conventional oxygen reference in previous solid-electrolyte oxygen sensor designs and is, therefore, ideally suited as an insertion device for remote oxygen monitoring applications. It is constructed with two cells of stabilized zirconia sealed into a small unit using a new high-temperature platinum-zirconia seal. One electrochemical cell monitors the ratio of oxygen partial pressures inside and outside the sensor while the other solid-electrolyte cell is used for quantitative electrochemical pumping of oxygen. The internal oxygen reference is generated by initially pumping all oxygen out of the known internal volume of the sensor and then quantitatively pumping oxygen back in until oxygen partial pressures are equal inside and out. This information is used with the ideal gas law to calculate oxygen partial pressures. Tests were conducted from 400 to 1000 0 C in mixtures of oxygen and nitrogen spanning approximately 0.2 to 21 percent oxygen concentration range. Sensors with sputtered platinum and porous platinum paste electrodes were compared

Electrolyte for batteries with regenerative solid electrolyte interface

Science.gov (United States)

Xiao, Jie; Lu, Dongping; Shao, Yuyan; Bennett, Wendy D.; Graff, Gordon L.; Liu, Jun; Zhang, Ji-Guang

2017-08-01

An energy storage device comprising: an anode; and a solute-containing electrolyte composition wherein the solute concentration in the electrolyte composition is sufficiently high to form a regenerative solid electrolyte interface layer on a surface of the anode only during charging of the energy storage device, wherein the regenerative layer comprises at least one solute or solvated solute from the electrolyte composition.

Global (volume-averaged) model of inductively coupled chlorine plasma : influence of Cl wall recombination and external heating on continuous and pulse-modulated plasmas

NARCIS (Netherlands)

Kemaneci, E.H.; Carbone, E.A.D.; Booth, J.P.; Graef, W.A.A.D.; Dijk, van J.; Kroesen, G.M.W.

An inductively coupled radio-frequency plasma in chlorine is investigated via a global (volume-averaged) model, both in continuous and square wave modulated power input modes. After the power is switched off (in a pulsed mode) an ion–ion plasma appears. In order to model this phenomenon, a novel

Effect of DC Plasma Electrolytic Oxidation on Surface Characteristics and Corrosion Resistance of Zirconium

Directory of Open Access Journals (Sweden)

Maciej Sowa

2018-05-01

Full Text Available Zr is a valve metal, the biocompatibility of which is at least on par with Ti. Recently, numerous attempts of the formation of bioactive coatings on Zr by plasma electrolytic oxidation (PEO in solutions that were based on calcium acetate and calcium β-glycerophosphate were made. In this study, the direct current (DC PEO of commercially pure zirconium in the solutions that contained Ca(H2PO22, Ca(HCOO2, and Mg(CH3COO2 was investigated. The treatment was conducted at 75 mA/cm2 up to 200, 300, or 400 V. Five process stages were discerned. The treatment at higher voltages resulted in the formation of oxide layers that had Ca/P or (Mg+Ca/P ratios that were close to that of hydroxyapatite (Ca/P = 1.67, determined by SEM/EDX. The corrosion resistance studies were performed using electrochemical impedance spectroscopy (EIS and DC polarization methods. R(Q[R(QR] circuit model was used to fit the EIS data. In general, the coatings that were obtained at 200 V were the most corrosion resistant, however, they lacked the porous structure, which is typical for PEO coatings, and is sought after in the biomedical applications. The treatment at 400 V resulted in the formation of the coatings that were more corrosion resistant than those that were obtained at 300 V. This was determined mainly by the prevailing plasma regime at the given process voltage. The pitting resistance of Zr was also improved by the treatment, regardless of the applied process conditions.

A plasma melting technology for volume reduction of noncombustible radioactive waste in Korea

International Nuclear Information System (INIS)

Song, Myung Jae; Moon, Young Pyo

1998-01-01

In Korea, there is a strong need for the development of radioactive waste volume reduction technology. Korea Electric Power Research Institute (KEPRI) has been searching for ways to reduce the radioactive volume significantly and to produce stable waste forms. In particular, plasma treatment technology has caught KEPR's attention for treating noncombustible radwaste because this technology may far surpass conventional methods. The potential for greater control of temperature, faster reaction times, better control of processing, lower capital costs, greater throughput and more efficient use of energy is there. For the plasma melting study of noncombustible waste, KEPRI has leased a lab scale multipurpose plasma furnace system and performed preliminary tests. Using simulated noncombustible waste based on field survey data from nuclear power plants, lab scale melting experiments have been carried out. The properties of molten slag vary with additives and noncombustible waste materials. KEPRI's current study is focused on finding an optimum composition ratio of various noncombustible wastes for melting, investigating physical properties of molten slag, and obtaining operating parameters for continuous operation. (author)

Lack of an association of BDNF Val66Met polymorphism and plasma BDNF with hippocampal volume and memory

Science.gov (United States)

Kim, Ana; Fagan, Anne M; Goate, Alison M; Benzinger, Tammie LS; Morris, John C; Head, Denise

2015-01-01

Brain-derived neurotrophic factor (BDNF) has been shown to be important for neuronal survival and synaptic plasticity in the hippocampus in non-human animals. The Val66Met polymorphism in the BDNF gene, involving a valine (Val) to methionine (Met) substitution at codon 66, has been associated with lower BDNF secretion in vitro. However, there have been mixed results regarding associations between either circulating BDNF or the BDNF Val66Met polymorphism with hippocampal volume and memory in humans. The current study examined the association of BDNF genotype and plasma BDNF with hippocampal volume and memory in two large independent cohorts of middle-aged and older adults (both cognitively normal and early-stage dementia). Sample sizes ranged from 123 to 649. Measures of the BDNF genotype, plasma BDNF, MRI-based hippocampal volume and memory performance were obtained from the Knight Alzheimer Disease Research Center (ADRC) and the Alzheimer’s Disease Neuroimaging Initiative (ADNI). There were no significant differences between BDNF Met+ and Met- groups on either hippocampal volume or memory in either cohort. In addition, plasma BDNF was not significantly associated with either hippocampal volume or memory in either cohort. Neither age, cognitive status nor gender moderated any of the relationships. Overall, current findings suggest that BDNF genotype and plasma BDNF may not be robust predictors for variance in hippocampal volume and memory in middle age and older adult cohorts. PMID:25784293

Composite gel polymer electrolyte for lithium ion batteries

Science.gov (United States)

Naderi, Roya

Composite gel polymer electrolyte (CGPE) films, consisting of poly (vinylidene fluoride-hexafluoropropylene) (PVdF-HFP) as the membrane, DMF and PC as solvent and plasticizing agent, mixture of charge modified TiO2 and SiO 2 nano particles as ionic conductors, and LiClO4+LiPF 6 as lithium salts were fabricated. Following the work done by Li et al., CGPE was coated on an O2-plasma treated trilayer polypropylene-polyethylene-polypropylene membrane separator using solution casting technique in order to improve the adhesive properties of gel polymer electrolyte to the separator membrane and its respective ionic conductivity due to decreasing the bulk resistance. In acidic CGPE with, the mixture of acid treated TiO2 and neutral SiO2 nano particles played the role of the charge modified nano fillers with enhanced hydroxyl groups. Likely, the mixture of neutral TiO 2 nano particles with basic SiO2 prepared through the hydrolization of tetraethyl orthosilicate (TEOS) provided a more basic environment due to the residues of NH4OH (Ammonium hydroxide) catalyst. The O2 plasma treated separator was coated with the solution of PVDF-HFP: modified nano fillers: Organic solvents with the mixture ratio of 0.1:0.01:1. After the evaporation of the organic solvents, the dried coated separator was soaked in PC-LiClO4+LiPF6 in EC: DMC:DEC (4:2:4 in volume) solution (300% wt. of PVDF-HFP) to form the final CGPE. Lim et al. has reported the enhanced ionic conductivity of 9.78*10-5 Scm-1 in an acidic composite polystyrene-Al2O3 solid electrolyte system with compared to that of basic and neutral in which the ionic conductivity undergoes an ion hopping process in solid interface rather than a segmental movement of ions through the plasticized polymer chain . Half-cells with graphite anode and Li metal as reference electrode were then assembled and the electrochemical measurements and morphology examinations were successfully carried out. Half cells demonstrated a considerable change in their

Systematic understanding of corrosion behavior of plasma electrolytic oxidation treated AZ31 magnesium alloy using a mouse model of subcutaneous implant.

Science.gov (United States)

Jang, Yongseok; Tan, Zongqing; Jurey, Chris; Collins, Boyce; Badve, Aditya; Dong, Zhongyun; Park, Chanhee; Kim, Cheol Sang; Sankar, Jagannathan; Yun, Yeoheung

2014-12-01

This study was conducted to identify the differences between corrosion rates, corrosion types, and corrosion products in different physiological environments for AZ31 magnesium alloy and plasma electrolytic oxidation (PEO) treated AZ31 magnesium alloy. In vitro and in vivo tests were performed in Hank's Balanced Salt Solution (HBSS) and mice for 12 weeks, respectively. The corrosion rates of both AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy were calculated based on DC polarization curves, volume of hydrogen evolution, and the thickness of corrosion products formed on the surface. Micro X-ray computed tomography (Micro-CT), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) were used to analyze morphological and chemical characterizations of corrosion products. The results show that there is more severe localized corrosion after in vitro test in HBSS; however, the thicknesses of corrosion products formed on the surface for AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy in vivo were about 40% thicker than the thickness of corrosion products generated in vitro. The ratio of Ca and P (Ca/P) in the corrosion products also differed. The Ca deficient region and higher content of Al in corrosion product than AZ31 magnesium alloy were identified after in vivo test in contrast with the result of in vitro test. Copyright © 2014 Elsevier B.V. All rights reserved.

Corrosion behaviors and effects of corrosion products of plasma electrolytic oxidation coated AZ31 magnesium alloy under the salt spray corrosion test

International Nuclear Information System (INIS)

Wang, Yan; Huang, Zhiquan; Yan, Qin; Liu, Chen; Liu, Peng; Zhang, Yi; Guo, Changhong; Jiang, Guirong; Shen, Dejiu

2016-01-01

Highlights: • Corrosion behaviors of a PEO coating was investigated after the salt spray test. • Corrosion products have significant effects on corrosion behaviors of the coating. • An electrochemical corrosion model is proposed. - Abstract: The effects of corrosion products on corrosion behaviors of AZ31 magnesium alloy with a plasma electrolytic oxidation (PEO) coating were investigated under the salt spray corrosion test (SSCT). The surface morphology, cross-sectional microstructure, chemical and phase compositions of the PEO coating were determined using scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction analysis (XRD), respectively. Further, the corrosion process of the samples under the SSCT was examined in a non-aqueous electrolyte (methanol) using electrochemical impedance spectroscopy (EIS) coupled with equivalent circuit. The results show that the inner layer of the coating was destroyed firstly and the corrosion products have significant effects on the corrosion behaviors of the coating. The results above are discussed and an electrochemical corrosion model is proposed in the paper.

Corrosion behaviors and effects of corrosion products of plasma electrolytic oxidation coated AZ31 magnesium alloy under the salt spray corrosion test

Energy Technology Data Exchange (ETDEWEB)

Wang, Yan; Huang, Zhiquan; Yan, Qin; Liu, Chen; Liu, Peng; Zhang, Yi [State Key Laboratory of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004 (China); Guo, Changhong; Jiang, Guirong [College of Mechanical Engineering, Yanshan University, Qinhuangdao 066004 (China); Shen, Dejiu, E-mail: DejiuShen@163.com [State Key Laboratory of Metastable Materials Science and Technology, College of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004 (China)

2016-08-15

Highlights: • Corrosion behaviors of a PEO coating was investigated after the salt spray test. • Corrosion products have significant effects on corrosion behaviors of the coating. • An electrochemical corrosion model is proposed. - Abstract: The effects of corrosion products on corrosion behaviors of AZ31 magnesium alloy with a plasma electrolytic oxidation (PEO) coating were investigated under the salt spray corrosion test (SSCT). The surface morphology, cross-sectional microstructure, chemical and phase compositions of the PEO coating were determined using scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction analysis (XRD), respectively. Further, the corrosion process of the samples under the SSCT was examined in a non-aqueous electrolyte (methanol) using electrochemical impedance spectroscopy (EIS) coupled with equivalent circuit. The results show that the inner layer of the coating was destroyed firstly and the corrosion products have significant effects on the corrosion behaviors of the coating. The results above are discussed and an electrochemical corrosion model is proposed in the paper.

Chemical stability of {gamma}-butyrolactone-based electrolytes for aluminium electrolytic capacitors

Energy Technology Data Exchange (ETDEWEB)

Ue, Makoto [Mitsubishi Chemical Corp., Tsukuba Research Center, Ibaraki (Japan); Takeda, Masayuki [Mitsubishi Chemical Corp., Tsukuba Research Center, Ibaraki (Japan); Suzuki, Yoko [Mitsubishi Chemical Corp., Tsukuba Research Center, Ibaraki (Japan); Mori, Shoichiro [Mitsubishi Chemical Corp., Tsukuba Research Center, Ibaraki (Japan)

1996-06-01

{gamma}-Butyrolactone-based electrolytes have been used as the operating electrolytes for aluminum electrolytic capacitors. The chemical stability of these electrolytes at elevated temperatures has been examined by monitoring the decrease in their electrolytic conductivities. The deteriorated electrolytes were analyzed by gas and liquid chromatography and the conductivity decrease was directly correlated with the loss of acid components. In quaternary ammonium hydrogen maleate/{gamma}-butyrolactone electrolytes, the maleate anion decomposed by decarboxylation resulting in a complex polymer containing polyester and polyacrylate structures. Quaternary ammonium benzoate/{gamma}-butyrolactone electrolytes decomposed by SN2 reactions giving alkyl benzoates and trialkylamines. The deterioration of the carboxylate salt/{gamma}-butyrolactone electrolytes was accelerated by electrolysis. (orig.)

Comparison of electrochemical corrosion behaviour of MgO and ZrO2 coatings on AM50 magnesium alloy formed by plasma electrolytic oxidation

International Nuclear Information System (INIS)

Liang, J.; Srinivasan, P. Bala; Blawert, C.; Dietzel, W.

2009-01-01

Two types of PEO coatings were produced on AM50 magnesium alloy using pulsed DC plasma electrolytic oxidation process in an alkaline phosphate and acidic fluozirconate electrolytes, respectively. The phase composition and microstructure of these PEO coatings were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The corrosion behaviour of the coated samples was evaluated by open circuit potential (OCP) measurements, potentiodynamic polarization tests, and electrochemical impedance spectroscopy (EIS) in neutral 0.1 M NaCl solution. The results showed that PEO coating prepared from alkaline phosphate electrolyte consisted of only MgO and on the other hand the one formed in acidic fluozirconate solution was mainly composed of ZrO 2 , MgF 2 . Electrochemical corrosion tests indicated that the phase composition of PEO coating has a significant effect on the deterioration process of coated magnesium alloy in this corrosive environment. The PEO coating that was composed of only MgO suffered from localized corrosion in the 50 h exposure studies, whereas the PEO coating with ZrO 2 compounds showed a much superior stability during the corrosion tests and provided an efficient corrosion protection. The results showed that the preparation of PEO coating with higher chemical stability compounds offers an opportunity to produce layers that could provide better corrosion protection to magnesium alloys.

Electrolyte creepage barrier for liquid electrolyte fuel cells

Science.gov (United States)

Li, Jian [Alberta, CA; Farooque, Mohammad [Danbury, CT; Yuh, Chao-Yi [New Milford, CT

2008-01-22

A dielectric assembly for electrically insulating a manifold or other component from a liquid electrolyte fuel cell stack wherein the dielectric assembly includes a substantially impermeable dielectric member over which electrolyte is able to flow and a barrier adjacent the dielectric member and having a porosity of less than 50% and greater than 10% so that the barrier is able to measurably absorb and chemically react with the liquid electrolyte flowing on the dielectric member to form solid products which are stable in the liquid electrolyte. In this way, the barrier inhibits flow or creepage of electrolyte from the dielectric member to the manifold or component to be electrically insulated from the fuel cell stack by the dielectric assembly.

The formation of tungsten doped Al{sub 2}O{sub 3}/ZnO coatings on aluminum by plasma electrolytic oxidation and their application in photocatalysis

Energy Technology Data Exchange (ETDEWEB)

Stojadinović, Stevan, E-mail: sstevan@ff.bg.ac.rs [University of Belgrade, Faculty of Physics, Studentski trg 12-16, 11000 Belgrade (Serbia); Vasilić, Rastko [University of Belgrade, Faculty of Physics, Studentski trg 12-16, 11000 Belgrade (Serbia); Radić, Nenad [University of Belgrade, Institute of Chemistry, Technology and Metallurgy, Department of Catalysis and Chemical Engineering, Njegoševa 12, 11000 Belgrade (Serbia); Tadić, Nenad [University of Belgrade, Faculty of Physics, Studentski trg 12-16, 11000 Belgrade (Serbia); Stefanov, Plamen [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Block 11, 1113 Sofia (Bulgaria); Grbić, Boško [University of Belgrade, Institute of Chemistry, Technology and Metallurgy, Department of Catalysis and Chemical Engineering, Njegoševa 12, 11000 Belgrade (Serbia)

2016-07-30

Highlights: • Tungsten doped Al{sub 2}O{sub 3}/ZnO coatings are formed by plasma electrolytic oxidation (PEO). • Coatings are mainly composed of alpha alumina, ZnO and metallic tungsten. • Photocatalytic activity of doped Al{sub 2}O{sub 3}/ZnO coatings is higher than of undoped ones. • The increase of photoluminescence corresponds to decrease of photocatalytic activity. • Tungsten acts as a charge trap to reduce the recombination rate of electron/hole pairs. - Abstract: Tungsten doped Al{sub 2}O{sub 3}/ZnO coatings are formed by plasma electrolytic oxidation of aluminum substrate in supporting electrolyte (0.1 M boric acid + 0.05 M borax + 2 g/L ZnO) with addition of different concentrations of Na{sub 2}WO{sub 4}·2H{sub 2}O. The morphology, crystal structure, chemical composition, and light absorption characteristics of formed surface coatings are investigated. The X-ray diffraction and X-ray photoelectron spectroscopy results indicate that formed surface coatings consist of alpha and gamma phase of Al{sub 2}O{sub 3}, ZnO, metallic tungsten and WO{sub 3}. Obtained results showed that incorporated tungsten does not have any influence on the absorption spectra of Al{sub 2}O{sub 3}/ZnO coatings, which showed invariable band edge at about 385 nm. The photocatalytic activity of undoped and tungsten doped Al{sub 2}O{sub 3}/ZnO coatings is estimated by the photodegradation of methyl orange. The photocatalytic activity of tungsten doped Al{sub 2}O{sub 3}/ZnO coatings is higher thanof undoped Al{sub 2}O{sub 3}/ZnO coatings; the best photocatalytic activity is ascribed to coatings formed in supporting electrolyte with addition of 0.3 g/L Na{sub 2}WO{sub 4}·2H{sub 2}O. Tungsten in Al{sub 2}O{sub 3}/ZnO coatings acts as a charge trap, thus reducing the recombination rate of photogenerated electron-hole pairs. The results of PL measurements are in agreement with photocatalytic activity. Declining PL intensity corresponds to increasing photocatalytic activity of the

The Application of Le Chatelier – Brown Principle for Interpretation of the Results of the LongLasting Fluctuations of the Electric Strength in Minor Volumes of Electrolytes

Directory of Open Access Journals (Sweden)

K. V. Glagolev

2015-01-01

Full Text Available The paper discusses a Le Chatelier – Brown principle to describe a balanced state in various physical problems. The Le Chatelier – Brown principle applications are demonstrated in problems of chemical thermodynamics, mechanics, electrodynamics as well as in descriptions of biosphere processes. The paper defines an inverse correlation for the Kullback's measure values of fluctuations of the electric strength in minor volumes of electrolytes on the density of entropy production in the environment. It shows that influence of dissipative processes on isolated electrolytic cell can be described using the Le Chatelier – Brown principle. The correlation coefficient of Kullback's measure values and density of entropy production in transformation of the Sun radiation into the Earth surface thermal radiation is calculated.

Performance enhancement of membrane electrode assemblies with plasma etched polymer electrolyte membrane in PEM fuel cell

Energy Technology Data Exchange (ETDEWEB)

Cho, Yong-Hun; Yoon, Won-Sub [School of Advanced Materials Engineering, Kookmin University, 861-1 Jeongneung-dong, Seongbuk-gu, Seoul 136-702 (Korea); Bae, Jin Woo; Cho, Yoon-Hwan; Lim, Ju Wan; Ahn, Minjeh; Jho, Jae Young; Sung, Yung-Eun [World Class University (WCU) program of Chemical Convergence for Energy and Environment (C2E2), School of Chemical and Biological Engineering, College of Engineering, Seoul National University (SNU), 599 Gwanak-Ro, Gwanak-gu, Seoul 151-744 (Korea); Kwon, Nak-Hyun [Fuel Cell Vehicle Team 3, Advanced Technology Center, Corporate Research and Development Division, Hyundai-Kia Motors, 104 Mabuk-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-912 (Korea)

2010-10-15

In this work, a surface modified Nafion 212 membrane was fabricated by plasma etching in order to enhance the performance of a membrane electrode assembly (MEA) in a polymer electrolyte membrane fuel cell. Single-cell performance of MEA at 0.7 V was increased by about 19% with membrane that was etched for 10 min compared to that with untreated Nafion 212 membrane. The MEA with membrane etched for 20 min exhibited a current density of 1700 mA cm{sup -2} at 0.35 V, which was 8% higher than that of MEA with untreated membrane (1580 mA cm{sup -2}). The performances of MEAs containing etched membranes were affected by complex factors such as the thickness and surface morphology of the membrane related to etching time. The structural changes and electrochemical properties of the MEAs with etched membranes were characterized by field emission scanning electron microscopy, Fourier transform-infrared spectrometry, electrochemical impedance spectroscopy, and cyclic voltammetry. (author)

High-compactness coating grown by plasma electrolytic oxidation on AZ31 magnesium alloy in the solution of silicate-borax

Science.gov (United States)

Shen, M. J.; Wang, X. J.; Zhang, M. F.

2012-10-01

A ceramic coating was formed on the surface of AZ31 magnesium alloy by plasma electrolytic oxidation (PEO) in the silicate solution with and without borax doped. The composition, morphology, elements and roughness as well as mechanical property of the coating were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and reciprocal-sliding tribometer. The results show that the PEO coating is mainly composed of magnesia. When using borax dope, boron element is permeating into the coating and the boron containing phase exist in the form of amorphous. In addition, the microhardness and compactness of the PEO coating are improved significantly due to doped borax.

Changes in plasma volume and baroreflex function following resistance exercise

Science.gov (United States)

Ploutz, L. L.; Tatro, D. L.; Dudley, G. A.; Convertino, V. A.

1993-01-01

The dynamics of change in plasma volume (PV) and baroreflex responses have been reported over 24 h immediately following maximal cycle exercise. The purpose of this study was to determine if PV and baroreflex showed similar changes for 24 h after resistance exercise. Eight men were studied on 2 test days, 1 week apart. On 1 day, per cent change (% delta) in PV was estimated at 0,3, and 6 h after resistance exercise using haematocrit and haemoglobin. Baseline PV was measured 24 h after exercise using Evans blue dye. The carotid baroreceptor-cardiac reflex response was measured before, and 3, 6, 9, 12, and 24 h post-exercise. Each subject performed six sets of the bench press and leg press with 10 repetitions per set with a load that induced failure within each set. On a control day, the protocol was used without exercise. Plasma volume did not change during the control day. There was a 20% decrease in PV immediately post-exercise; the recovery of the PV was rapid and complete within 3 h. PV was 20% greater 24 h post-exercise than on the control day. There were no differences in any of the baroreflex measurements. Therefore, it is suggested that PV shifts may occur without altering baroreflex sensitivity.

Plasma electrolytic oxidation of AZ91D magnesium alloy with different additives and its corrosion behavior

Energy Technology Data Exchange (ETDEWEB)

Cao, Fa-he; Cao, Jiang-lin; Zhang, Zhao [Department of Chemistry, Zhejiang University, Hangzhou 310027 (China); Zhang, Jian-qing; Cao, Chu-nan [Department of Chemistry, Zhejiang University, Hangzhou 310027 (China); State Key Laboratory for Corrosion and Protection, Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110016 (China)

2007-09-15

Plasma electrolytic oxidation (PEO) of Mg-based AZ91D alloys was investigated using 50 Hz AC anodizing technique in an alkaline borate solution, which contained a new kind of organic additive and without F, P, and Cr. The anodizing technological parameters have been optimized and a kind of ivory-white smooth anodic film with high corrosion resistance was obtained. It was found that the formation of the anodic films was always coupled with sparking and oxygen evolution, whose intensity changed with the additive and anodizing voltage. All EIS plots have two capacitive loops and one low frequency inductive component. Two capacitive arcs present the barrier and porous layer of the PEO film and the inductive component in the low frequency domain is a complex behavior due to the porous structure connected to the electrolyte. EIS plots and fitting results show that a self-sealing process of the PEO firm with different additives takes place in the beginning of immersion time, then corrosion attack becomes a preponderant process to promote the degradation of the film. Tafel results show that PEO treatment decreases the corrosion current density by four, even five orders of magnitude, while additives content does not affect strongly the electrochemical corrosion behavior. Salt spray test shows that the PEO film formed with NaAlO{sub 2} and Na{sub 2}SiO{sub 3} presents good corrosion resistance, over 600 h without any sealing treatment. The difference of corrosion resistance arose by additives examined by electrochemical techniques and salt spray test does not show strict corresponding relationship. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

Electrical property of EDLC and electrochemical interaction between separator and electrolyte

Directory of Open Access Journals (Sweden)

Yukinari Hirai

2016-01-01

Full Text Available The electric double-layer capacitor (EDLC is an energy storage device that uses the movement of ions and is a battery with minimal deterioration. The increase of electrostatic capacity and the reduction of internal resistance are necessary for the use of ELDCs in various fields. The performance of EDLC is evaluated using 12 characteristics of separators. EDLC was measured by using the time constant method. The material, porosity, thickness, and hydrophilic processing (i.e. plasma hydrophilic treatment or fluorine gas hydrophilic treatment of the separator changed. Four important points were observed. First, the capacitance was changed by the amount of the electrolyte retained by the separator. Second, polyphenylene sulfide is a suitable fiber for the retention of electrolyte. Third, the capacitance increased with the application of a plasma hydrophilic treatment on the separator. Finally, thickness affects the capacitance more than porosity does.

Corrosion and nanomechanical behaviors of plasma electrolytic oxidation coated AA7020-T6 aluminum alloy

Energy Technology Data Exchange (ETDEWEB)

Venugopal, A., E-mail: arjun_venu@hotmail.com [Materials and Metallurgy Group, Materials and Mechanical Entity, Vikram Sarabhai Space Centre, Thiruvananthapuram (India); Srinath, J. [Materials and Metallurgy Group, Materials and Mechanical Entity, Vikram Sarabhai Space Centre, Thiruvananthapuram (India); Rama Krishna, L. [International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Balapur P.O., Hyderabad 500005 (India); Ramesh Narayanan, P.; Sharma, S.C.; Venkitakrishnan, P.V. [Materials and Metallurgy Group, Materials and Mechanical Entity, Vikram Sarabhai Space Centre, Thiruvananthapuram (India)

2016-04-13

Alumina coating was deposited on AA7020 aluminum alloy by plasma electrolytic oxidation (PEO) method. The corrosion, stress corrosion cracking (SCC) and nano-mechanical behaviors were examined by means of potentiodynamic polarization, slow strain rate test (SSRT) and nano-indentation tests. Potentiodynamic polarization (PP) was used to evaluate the corrosion resistance of the coating and slow strain rate test (SSRT) was used for evaluating the environmental cracking resistance in 3.5% NaCl solution. The mechanical properties (hardness and elastic modulus) were obtained from each indentation as a function of the penetration depth across the coating cross section. The above results were compared with similar PEO coated aluminum and magnesium alloys. Results indicated that PEO coating on AA7020 alloy significantly improved the corrosion resistance. However the environmental cracking resistance was found to be only marginal. The hardness and elastic modulus values were found to be much higher when compared to the base metal and similar PEO coated 7075 aluminum alloys. The fabricated coating also exhibited good adhesive strength with the substrate similar to other PEO coated aluminum alloys reported in the literature.

High Current Plasma Electrolytic Oxidation Coating Processes for Wear and Corrosion Prevention of Al 2024

Science.gov (United States)

Wang, Rui

Plasma electrolytic oxidation (PEO) treatments have been used in the aerospace and automotive industries because the coating formed on light metals or alloys has great hardness, high wear, corrosion, and oxidation resistance, and a low friction coefficient that improves lifetime length and provide a higher surface quality. However, the PEO treatments that are presently used for industrial applications require a long period of time to confirm the quality of the coating. For this reason, the present study seeks to increase the current density of PEO treatments to improve their efficiency and explore the performance of the obtained coatings. It was found that for high current density (0.18A/cm2) PEO treatments, smaller ratio, such as 50% and 70%, is beneficial to obtaining a better performance coating. When compared with the coating of a "normal" (current density: 0.09A/cm2) PEO treatment, it had better wear resistance; however, for corrosion resistance, it had a lower performance than the coatings obtained by the "normal" current density PEO treatment which was attributed to the negative influence of porosity increase.

Electrolytic installation in order to obtain deuterium and to fill the pressure deposits

International Nuclear Information System (INIS)

Cordero Lopez, F.; Tanarro Sanz, A.

1959-01-01

In order to obtain deuterium to feed the ion sources of the accelerators an easy and automatic electrolytic installation has been prepared. this installation and a small compressor designed and constructed for this purpose permit to fill deposits of 1 or 2 liters capacity with deuterium, till a 4 atmosphere pressure in few hours of operation. The electrolytic cell has V shape and permits operation with 3 cc heavy water only as it has small dead volume; the electrodes are platinum and as electrolyte an OH Na solution in a proportion of 15 w/o is used. (Author) 3 refs

An electrochemical analysis of AZ91 Mg alloy processed by plasma electrolytic oxidation followed by static annealing

Energy Technology Data Exchange (ETDEWEB)

Ko, Y.G. [School of Materials Science and Engineering, Yeungnam University, 214-1 Dae-Dong, Gyeongsan 712-749, Gyeongbuk (Korea, Republic of); Lee, K.M.; Lee, B.U. [Department of Metallurgy and Materials Engineering, Hanyang University, Ansan 425-791 (Korea, Republic of); Shin, D.H., E-mail: dhshin@hanyang.ac.kr [Department of Metallurgy and Materials Engineering, Hanyang University, Ansan 425-791 (Korea, Republic of)

2011-06-15

Research highlights: > The amount of MgO in the oxide film increased with increasing annealing temperature. > The dehydration reaction resulted in the formation of micro-cracks in the oxide film. > Electrochemical response of the PEO-treated sample annealed at 150 deg. C was improved. - Abstract: In this study, the effect of subsequent annealing on the electrochemical response of AZ91 Mg alloy coated via plasma electrolytic oxidation (PEO) was investigated. PEO coating was carried out on the Mg alloy under AC condition in an alkaline silicate electrolyte, and the PEO-coated samples underwent several subsequent annealing treatments at three different temperatures of 100, 150, and 200 deg. C. The surface morphologies of the coating layers were observed via a scanning electron microscope (SEM) and their constituent compounds were characterized by qualitative observation based on X-ray photoelectron spectroscopy (XPS). In addition, the corrosion protection properties of the PEO-coated sample were examined by electrochemical impedance spectroscopy (EIS) in a 3.5 wt% NaCl solution with a focus on exploring the effect of subsequent annealing on the electrochemical response in a quantitative manner. SEM and XPS observations evidenced that the subsequent annealing at temperatures higher than 150 deg. C resulted in significant morphological changes due to the dehydration reaction of Mg(OH){sub 2} to form MgO. Thus, it was found that the sample annealed at 150 deg. C exhibited a better corrosion resistance than the other samples, which were analyzed by taking an equivalent circuit model into account.

Performance of large electron energy filter in large volume plasma device

International Nuclear Information System (INIS)

Singh, S. K.; Srivastava, P. K.; Awasthi, L. M.; Mattoo, S. K.; Sanyasi, A. K.; Kaw, P. K.; Singh, R.

2014-01-01

This paper describes an in-house designed large Electron Energy Filter (EEF) utilized in the Large Volume Plasma Device (LVPD) [S. K. Mattoo, V. P. Anita, L. M. Awasthi, and G. Ravi, Rev. Sci. Instrum. 72, 3864 (2001)] to secure objectives of (a) removing the presence of remnant primary ionizing energetic electrons and the non-thermal electrons, (b) introducing a radial gradient in plasma electron temperature without greatly affecting the radial profile of plasma density, and (c) providing a control on the scale length of gradient in electron temperature. A set of 19 independent coils of EEF make a variable aspect ratio, rectangular solenoid producing a magnetic field (B x ) of 100 G along its axis and transverse to the ambient axial field (B z ∼ 6.2 G) of LVPD, when all its coils are used. Outside the EEF, magnetic field reduces rapidly to 1 G at a distance of 20 cm from the center of the solenoid on either side of target and source plasma. The EEF divides LVPD plasma into three distinct regions of source, EEF and target plasma. We report that the target plasma (n e ∼ 2 × 10 11  cm −3 and T e ∼ 2 eV) has no detectable energetic electrons and the radial gradients in its electron temperature can be established with scale length between 50 and 600 cm by controlling EEF magnetic field. Our observations reveal that the role of the EEF magnetic field is manifested by the energy dependence of transverse electron transport and enhanced transport caused by the plasma turbulence in the EEF plasma

Soft plasma electrolysis with complex ions for optimizing electrochemical performance

Science.gov (United States)

Kamil, Muhammad Prisla; Kaseem, Mosab; Ko, Young Gun

2017-03-01

Plasma electrolytic oxidation (PEO) was a promising surface treatment for light metals to tailor an oxide layer with excellent properties. However, porous coating structure was generally exhibited due to excessive plasma discharges, restraining its performance. The present work utilized ethylenediaminetetraacetic acid (EDTA) and Cu-EDTA complexing agents as electrolyte additives that alter the plasma discharges to improve the electrochemical properties of Al-1.1Mg alloy coated by PEO. To achieve this purpose, PEO coatings were fabricated under an alternating current in silicate electrolytes containing EDTA and Cu-EDTA. EDTA complexes were found to modify the plasma discharging behaviour during PEO that led to a lower porosity than that without additives. This was attributed to a more homogeneous electrical field throughout the PEO process while the coating growth would be maintained by an excess of dissolved Al due to the EDTA complexes. When Cu-EDTA was used, the number of discharge channels in the coating layer was lower than that with EDTA due to the incorporation of Cu2O and CuO altering the dielectric behaviour. Accordingly, the sample in the electrolyte containing Cu-EDTA constituted superior corrosion resistance to that with EDTA. The electrochemical mechanism for excellent corrosion protection was elucidated in the context of equivalent circuit model.

Solution phase thermodynamics of strong electrolytes based on ionic concentrations, hydration numbers and volumes of dissolved entities

Czech Academy of Sciences Publication Activity Database

Heyrovská, Raji

2013-01-01

Roč. 24, č. 6 (2013), s. 1895-1901 ISSN 1040-0400 Institutional support: RVO:68081707 Keywords : Solution thermodynamics * Aqueous electrolytes * Partial electrolytic dissociation Subject RIV: BO - Biophysics Impact factor: 1.900, year: 2013

Supercapacitor Electrolyte Solvents with Liquid Range Below -80 C

Science.gov (United States)

Brandon, Erik; Smart, Marshall; West, William

2010-01-01

A previous NASA Tech Brief ["Low-Temperature Supercapacitors" (NPO-44386) NASA Tech Briefs, Vol. 32, No 7 (July 2008), page 32] detailed ongoing efforts to develop non-aqueous supercapacitor electrolytes capable of supporting operation at temperatures below commercially available cells (which are typically limited to charging and discharging at > or equal to -40 C). These electrolyte systems may enable energy storage and power delivery for systems operating in extreme environments, such as those encountered in the Polar regions on Earth or in the exploration of space. Supercapacitors using these electrolytes may also offer improved power delivery performance at moderately low temperatures (e.g. -40 to 0 C) relative to currently available cells, offering improved cold-cranking and cold-weather acceleration capabilities for electrical or hybrid vehicles. Supercapacitors store charge at the electrochemical double-layer, formed at the interface between a high surface area electrode material and a liquid electrolyte. The current approach to extending the low-temperature limit of the electrolyte focuses on using binary solvent systems comprising a high-dielectric-constant component (such as acetonitrile) in conjunction with a low-melting-point co-solvent (such as organic formates, esters, and ethers) to depress the freezing point of the system, while maintaining sufficient solubility of the salt. Recent efforts in this area have led to the identification of an electrolyte solvent formulation with a freezing point of -85.7 C, which is achieved by using a 1:1 by volume ratio of acetonitrile to 1,3-dioxolane

Impact of Plasma Epstein-Barr Virus-DNA and Tumor Volume on Prognosis of Locally Advanced Nasopharyngeal Carcinoma

Directory of Open Access Journals (Sweden)

Meng Chen

2015-01-01

Full Text Available This retrospective study aims to examine the association of plasma Epstein-Barr virus- (EBV- DNA levels with the tumor volume and prognosis in patients with locally advanced nasopharyngeal carcinoma (NPC. A total of 165 patients with newly diagnosed locally advanced NPC were identified from September 2011 to July 2012. EBV-DNA was detected using fluorescence quantitative polymerase chain reaction (PCR amplification. The tumor volume was calculated by the systematic summation method of computer software. The median copy number of plasma EBV-DNA before treatment was 3790 copies/mL. The median gross tumor volume of the primary nasopharyngeal tumor (GTVnx, the lymph node lesions (GTVnd, and the total GTV before treatment were 72.46, 23.26, and 106.25 cm3, respectively; the EBV-DNA levels were significantly correlated with the GTVnd and the total GTV (P<0.01. The 2-year overall survival (OS rates in patients with positive and negative pretreatment plasma EBV-DNA were 100% and 98.4% (P=1.000, and the disease-free survival (DFS rates were 94.4% and 80.8% (P=0.044, respectively. These results indicate that high pretreatment plasma EBV-DNA levels in patients with locally advanced NPC are associated with the degree of lymph node metastasis, tumor burden, and poor prognosis.

Structure, tribocorrosion and biocide characterization of Ca, P and I containing TiO{sub 2} coatings developed by plasma electrolytic oxidation

Energy Technology Data Exchange (ETDEWEB)

Sáenz de Viteri, V., E-mail: virginia.saenzdeviteri@tekniker.es [IK4-Tekniker, Polo Tecnológico de Eibar, Calle Iñaki Goenaga, 5, Eibar 20600 (Spain); Bayón, R.; Igartua, A. [IK4-Tekniker, Polo Tecnológico de Eibar, Calle Iñaki Goenaga, 5, Eibar 20600 (Spain); Barandika, G. [Departamento de Química Inorgánica, Facultad de Ciencia y Tecnología, Universidad del País Vasco, UPV/EHU, Apartado 644, Bilbao E-48080 (Spain); Moreno, J. Esteban; Peremarch, C. Pérez-Jorge; Pérez, M. Martínez [Department of Clinical Microbiology, IIS-Fundación Jiménez Díaz, Av. Reyes Católicos 2, Madrid 28040 (Spain)

2016-03-30

Graphical abstract: - Highlights: • Ca, P and I doped TiO{sub 2} coatings were developed by means of plasma electrolytic oxidation (PEO) technique. • Microstructure and chemical composition of the developed coating were in depth analyzed. • The effect of wear-corrosion synergy was studied through tribocorrosion tests. • Antibacterial efficiency of iodine as biocide agent was analyzed by means of bacterial adhesion study. • A TiO{sub 2} coating with improved wear-corrosion resistance, suitable surface for cell adhesion and biocide properties was achieved. - Abstract: In hip joint implants, in particular in the stems, wear-corrosion effects can accelerate the degradation of the biomaterial. The lack of osseointegration and the risk of contracting implant-associated infections may be other reasons for a premature failure of the implant. In this work, TiO{sub 2} coatings have been developed by means of plasma electrolytic oxidation (PEO) technique in order to achieve wear-resistant hard coatings with osseointegration ability and biocide characteristics. During the PEO process, elements that favor cell growth, like Ca and P, were introduced into the coating. With the purpose of providing the coating with antibacterial properties iodine was added like biocide agent. The microstructure and chemical composition of the developed coatings were analyzed in order to see if the surface of the films was suitable for the cell attachment. The effect of wear-corrosion synergy was studied by means of tribocorrosion tests. Finally, the biocide capacity of iodine against Staphylococcus aureus and Staphylococcus epidermidis was analyzed through bacterial adhesion tests. High wear and corrosion resistance was shown in one of the developed coatings. The achieved surface microstructures seem to be appropriate to improve the osseointegration with proper pore size and porosity index. The antibacterial capacity of iodine was confirmed for S. epidermidis.

Understanding corrosion behavior of Mg–Zn–Ca alloys from subcutaneous mouse model: Effect of Zn element concentration and plasma electrolytic oxidation

Energy Technology Data Exchange (ETDEWEB)

Jang, Yongseok [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC 27411 (United States); Tan, Zongqing [Department of Internal Medicine, College of Medicine, University of Cincinnati, Cincinnati, OH 45221 (United States); Jurey, Chris [Luke Engineering, Wadsworth, OH 44282 (United States); Xu, Zhigang [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC 27411 (United States); Dong, Zhongyun [Department of Internal Medicine, College of Medicine, University of Cincinnati, Cincinnati, OH 45221 (United States); Collins, Boyce [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC 27411 (United States); Yun, Yeoheung, E-mail: yyun@ncat.edu [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC 27411 (United States); Sankar, Jagannathan [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC 27411 (United States)

2015-03-01

Mg–Zn–Ca alloys are considered as suitable biodegradable metallic implants because of their biocompatibility and proper physical properties. In this study, we investigated the effect of Zn concentration of Mg–xZn–0.3Ca (x = 1, 3 and 5 wt.%) alloys and surface modification by plasma electrolytic oxidation (PEO) on corrosion behavior in in vivo environment in terms of microstructure, corrosion rate, types of corrosion, and corrosion product formation. Microstructure analysis of alloys and morphological characterization of corrosion products were conducted using x-ray computed tomography (micro-CT) and scanning electron microscopy (SEM). Elemental composition and crystal structure of corrosion products were determined using x-ray diffraction (XRD) and electron dispersive x-ray spectroscopy (EDX). The results show that 1) as-cast Mg–xZn–0.3Ca alloys are composed of Mg matrix and a secondary phase of Ca{sub 2}Mg{sub 6}Zn{sub 3} formed along grain boundaries, 2) the corrosion rate of Mg–xZn–0.3Ca alloys increases with increasing concentration of Zn in the alloy, 3) corrosion rates of alloys treated by PEO sample are decreased in in vivo environment, and 4) the corrosion products of these alloys after in vivo tests are identified as brucite (Mg(OH){sub 2}), hydroxyapatite (Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}), and magnesite (MgCO{sub 3}·3H{sub 2}O). - Highlights: • Effects of PEO and Zn concentration in Mg–xZn–0.3Ca alloys on biodegradation • Corrosion rate of Mg–xZn–0.3Ca alloys increases with increasing Zn concentration. • Plasma electrolytic oxidation retards the biodegradation of Mg–xZn–0.3Ca alloys.

Dye-Sensitized Solar Cells with Optimal Gel Electrolyte Using the Taguchi Design Method

Directory of Open Access Journals (Sweden)

Jenn-Kai Tsai

2013-01-01

Full Text Available The Taguchi method was adopted to determine the optimal gel electrolyte used in dye-sensitized solar cells (DSSCs. Since electrolyte is a very important factor in fabrication of high performance and long-term stability DSSCs, to find the optimal composition of gel electrolyte is desired. In this paper, the common ingredients used in the liquid electrolyte were chosen. The ingredients then mixed with cheap ionic liquids and poly(vinylidenefluoride-co-hexafluoropropylene (PVDF-HFP were added to form colloidal electrolyte (gel. The optimal composition of each materials in the gel electrolyte determined by Taguchi method consists of 0.03 M I2, 0.15 M KI, 0.6 M LiI, 0.5 M 4-tertbutylpyridine (TBP, and 10% PVDF-HFP dissolved in the acetonitrile and 3-methoxypropionitrile (MPN solution with volume ratio of 2 : 1. The short circuit current density of 14.11 mA/cm2, the conversion efficiency (η of 5.52%, and the lifetime of over 110 days were observed for the dye-sensitized solar cell assembled with optimal gel electrolyte. The lifetime increases 10 times when compared with the conventional dye-sensitized solar cell assembled with liquid electrolyte.

Serum Trace Elements and Electrolytes Are Associated with Fasting Plasma Glucose and HbA1c in Postmenopausal Women with Type 2 Diabetes Mellitus.

Science.gov (United States)

Skalnaya, Margarita G; Skalny, Anatoly V; Yurasov, Vasily V; Demidov, Vasily A; Grabeklis, Andrei R; Radysh, Ivan V; Tinkov, Alexey A

2017-05-01

The primary aim of the research was to assess the level of trace elements and electrolytes in serum of postmenopausal diabetic women. Sixty-four postmenopausal women with type 2 diabetes mellitus (DM2) and 64 age- and body mass index-matched controls were examined. Serum trace elements were assessed using inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS). Fasting plasma glucose (FPG) and glycated hemoglobin (HbA 1c ) levels were evaluated using Randox kits. The obtained data demonstrate that DM2 patients were characterized by 42 and 34 % higher FPG and HbA 1c levels, respectively (p women was increased by 10 and 15 % in comparison to the respective control values (p = 0.002 and DM2 pathogenesis. Further studies are required to assess the intimate mechanisms of the observed differences.

Electro-mechanical probe positioning system for large volume plasma device

Science.gov (United States)

Sanyasi, A. K.; Sugandhi, R.; Srivastava, P. K.; Srivastav, Prabhakar; Awasthi, L. M.

2018-05-01

An automated electro-mechanical system for the positioning of plasma diagnostics has been designed and implemented in a Large Volume Plasma Device (LVPD). The system consists of 12 electro-mechanical assemblies, which are orchestrated using the Modbus communication protocol on 4-wire RS485 communications to meet the experimental requirements. Each assembly has a lead screw-based mechanical structure, Wilson feed-through-based vacuum interface, bipolar stepper motor, micro-controller-based stepper drive, and optical encoder for online positioning correction of probes. The novelty of the system lies in the orchestration of multiple drives on a single interface, fabrication and installation of the system for a large experimental device like the LVPD, in-house developed software, and adopted architectural practices. The paper discusses the design, description of hardware and software interfaces, and performance results in LVPD.

Fluid and electrolyte disturbances in critically ill patients.

Science.gov (United States)

Lee, Jay Wook

2010-12-01

Disturbances in fluid and electrolytes are among the most common clinical problems encountered in the intensive care unit (ICU). Recent studies have reported that fluid and electrolyte imbalances are associated with increased morbidity and mortality among critically ill patients. To provide optimal care, health care providers should be familiar with the principles and practice of fluid and electrolyte physiology and pathophysiology. Fluid resuscitation should be aimed at restoration of normal hemodynamics and tissue perfusion. Early goal-directed therapy has been shown to be effective in patients with severe sepsis or septic shock. On the other hand, liberal fluid administration is associated with adverse outcomes such as prolonged stay in the ICU, higher cost of care, and increased mortality. Development of hyponatremia in critically ill patients is associated with disturbances in the renal mechanism of urinary dilution. Removal of nonosmotic stimuli for vasopressin secretion, judicious use of hypertonic saline, and close monitoring of plasma and urine electrolytes are essential components of therapy. Hypernatremia is associated with cellular dehydration and central nervous system damage. Water deficit should be corrected with hypotonic fluid, and ongoing water loss should be taken into account. Cardiac manifestations should be identified and treated before initiating stepwise diagnostic evaluation of dyskalemias. Divalent ion deficiencies such as hypocalcemia, hypomagnesemia and hypophosphatemia should be identified and corrected, since they are associated with increased adverse events among critically ill patients.

PE-g-MMA polymer electrolyte membrane for lithium polymer battery

Energy Technology Data Exchange (ETDEWEB)

Gao Kun [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)]. E-mail: gaokun@hit.edu.cn; Hu Xinguo [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Yi Tingfeng [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Dai Changsong [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)

2006-10-25

PE-g-MMA membranes with different degrees of grafting (DG) were prepared by electron beam radiation-induced graft copolymerization of methylmethacrylate (MMA) monomer onto polyethylene (PE) separator. The grafted membranes (GMs) were characterized using SEM, FTIR. The new polymer electrolytes based on GMs were prepared through immersion in a solution of LiPF{sub 6}-EC/DMC (1:1 by volume). It was found that the GMs with different DG exhibited the different uptake and retention ability of liquid electrolyte. Moreover, the ion conductivities of activated polymer electrolytes (APEs) were also found to vary with the different DG and reached a magnitude of 10{sup -3} S cm{sup -1} at the DG of 42%. Compared with those containing PE separators, the LiCoO{sub 2}-MCMB coin cells containing GMs demonstrated better cycle life and excellent rate performance.

PE-g-MMA polymer electrolyte membrane for lithium polymer battery

International Nuclear Information System (INIS)

Gao Kun; Hu Xinguo; Yi Tingfeng; Dai Changsong

2006-01-01

PE-g-MMA membranes with different degrees of grafting (DG) were prepared by electron beam radiation-induced graft copolymerization of methylmethacrylate (MMA) monomer onto polyethylene (PE) separator. The grafted membranes (GMs) were characterized using SEM, FTIR. The new polymer electrolytes based on GMs were prepared through immersion in a solution of LiPF 6 -EC/DMC (1:1 by volume). It was found that the GMs with different DG exhibited the different uptake and retention ability of liquid electrolyte. Moreover, the ion conductivities of activated polymer electrolytes (APEs) were also found to vary with the different DG and reached a magnitude of 10 -3 S cm -1 at the DG of 42%. Compared with those containing PE separators, the LiCoO 2 -MCMB coin cells containing GMs demonstrated better cycle life and excellent rate performance

PE-g-MMA polymer electrolyte membrane for lithium polymer battery

Energy Technology Data Exchange (ETDEWEB)

Gao, Kun; Hu, Xinguo; Yi, Tingfeng; Dai, Changsong [Departments of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)

2006-10-25

PE-g-MMA membranes with different degrees of grafting (DG) were prepared by electron beam radiation-induced graft copolymerization of methylmethacrylate (MMA) monomer onto polyethylene (PE) separator. The grafted membranes (GMs) were characterized using SEM, FTIR. The new polymer electrolytes based on GMs were prepared through immersion in a solution of LiPF{sub 6}-EC/DMC (1:1 by volume). It was found that the GMs with different DG exhibited the different uptake and retention ability of liquid electrolyte. Moreover, the ion conductivities of activated polymer electrolytes (APEs) were also found to vary with the different DG and reached a magnitude of 10{sup -3}Scm{sup -1} at the DG of 42%. Compared with those containing PE separators, the LiCoO{sub 2}-MCMB coin cells containing GMs demonstrated better cycle life and excellent rate performance. (author)

Preparation and in vitro evaluation of nanostructured TiO2/TCP composite coating by plasma electrolytic oxidation

International Nuclear Information System (INIS)

Hu, Hongjie; Liu, Xuanyong; Ding, Chuanxian

2010-01-01

Porous and nanostructured TiO 2 /tricalcium phosphate (TCP) composite coating on titanium substrate was prepared by plasma electrolytic oxidation (PEO). The microstructure and phase composition of the coating were characterized using scanning electron microscopy and X-ray diffraction. Its bioactivity was evaluated by simulated body fluid (SBF) immersion tests. MG63 cells were cultured on the surface of the coating to investigate its cytocompatibility. Potentiodynamic polarization tests were applied to measure its corrosion resistance. The results revealed that rough and hydrophilic TiO 2 /TCP composite coating with pores of several micrometers and grains of 50-200 nm was prepared by one-step PEO treatment. The TiO 2 /TCP composite coating showed good apatite-forming ability in SBF, and the TCP phase in the coating played an important role in inducing apatite formation. MG63 cells could adhere and proliferate on the surface of the coating, indicating its good cytocompatibility. The composite coating also exhibited good corrosion resistance in 0.9% NaCl solution.

Plasma properties in a large-volume, cylindrical and asymmetric radio-frequency capacitively coupled industrial-prototype reactor

International Nuclear Information System (INIS)

Lazović, Saša; Puač, Nevena; Spasić, Kosta; Malović, Gordana; Petrović, Zoran Lj; Cvelbar, Uroš; Mozetič, Miran; Radetić, Maja

2013-01-01

We have developed a large-volume low-pressure cylindrical plasma reactor with a size that matches industrial reactors for treatment of textiles. It was shown that it efficiently produces plasmas with only a small increase in power as compared with a similar reactor with 50 times smaller volume. Plasma generated at 13.56 MHz was stable from transition to streamers and capable of long-term continuous operation. An industrial-scale asymmetric cylindrical reactor of simple design and construction enabled good control over a wide range of active plasma species and ion concentrations. Detailed characterization of the discharge was performed using derivative, Langmuir and catalytic probes which enabled determination of the optimal sets of plasma parameters necessary for successful industry implementation and process control. Since neutral atomic oxygen plays a major role in many of the material processing applications, its spatial profile was measured using nickel catalytic probe over a wide range of plasma parameters. The spatial profiles show diffusion profiles with particle production close to the powered electrode and significant wall losses due to surface recombination. Oxygen atom densities range from 10 19 m −3 near the powered electrode to 10 17 m −3 near the wall. The concentrations of ions at the same time are changing from 10 16 to the 10 15 m −3 at the grounded chamber wall. (paper)

Osseointegration improvement by plasma electrolytic oxidation of modified titanium alloys surfaces.

Science.gov (United States)

Echeverry-Rendón, Mónica; Galvis, Oscar; Quintero Giraldo, David; Pavón, Juan; López-Lacomba, José Luis; Jiménez-Piqué, Emilio; Anglada, Marc; Robledo, Sara M; Castaño, Juan G; Echeverría, Félix

2015-02-01

Titanium (Ti) is a material frequently used in orthopedic applications, due to its good mechanical properties and high corrosion resistance. However, formation of a non-adherent fibrous tissue between material and bone drastically could affect the osseointegration process and, therefore, the mechanical stability of the implant. Modifications of topography and configuration of the tissue/material interface is one of the mechanisms to improve that process by manipulating parameters such as morphology and roughness. There are different techniques that can be used to modify the titanium surface; plasma electrolytic oxidation (PEO) is one of those alternatives, which consists of obtaining porous anodic coatings by controlling parameters such as voltage, current, anodizing solution and time of the reaction. From all of the above factors, and based on previous studies that demonstrated that bone cells sense substrates features to grow new tissue, in this work commercially pure Ti (c.p Ti) and Ti6Al4V alloy samples were modified at their surface by PEO in different anodizing solutions composed of H2SO4 and H3PO4 mixtures. Treated surfaces were characterized and used as platforms to grow osteoblasts; subsequently, cell behavior parameters like adhesion, proliferation and differentiation were also studied. Although the results showed no significant differences in proliferation, differentiation and cell biological activity, overall results showed an important influence of topography of the modified surfaces compared with polished untreated surfaces. Finally, this study offers an alternative protocol to modify surfaces of Ti and their alloys in a controlled and reproducible way in which biocompatibility of the material is not compromised and osseointegration would be improved.

Nanoporous polymer electrolyte

Science.gov (United States)

Elliott, Brian [Wheat Ridge, CO; Nguyen, Vinh [Wheat Ridge, CO

2012-04-24

A nanoporous polymer electrolyte and methods for making the polymer electrolyte are disclosed. The polymer electrolyte comprises a crosslinked self-assembly of a polymerizable salt surfactant, wherein the crosslinked self-assembly includes nanopores and wherein the crosslinked self-assembly has a conductivity of at least 1.0.times.10.sup.-6 S/cm at 25.degree. C. The method of making a polymer electrolyte comprises providing a polymerizable salt surfactant. The method further comprises crosslinking the polymerizable salt surfactant to form a nanoporous polymer electrolyte.

Enhancement of H{sup -}/D{sup -} volume production in a double plasma type negative ion source

Energy Technology Data Exchange (ETDEWEB)

Fukumasa, Osamu; Nishimura, Hideki; Sakiyama, Satoshi [Yamaguchi Univ., Ube (Japan). Faculty of Engineering

1997-02-01

H{sup -}/D{sup -} production in a pure volume source has been studied. In our double plasma type negative ion source, both energy and density of fast electrons are well controlled. With the use of this source, the enhancement of H{sup -}/D{sup -} production has been observed. Namely, under the same discharge power, the extracted H{sup -}/D{sup -} current in the double plasma operation is higher than that in the single plasma operation. At the same time, measurements of plasma parameters have been made in the source and the extractor regions for these two cases. (author)

Effects of Beer, Non-Alcoholic Beer and Water Consumption before Exercise on Fluid and Electrolyte Homeostasis in Athletes

Directory of Open Access Journals (Sweden)

Mauricio Castro-Sepulveda

2016-06-01

Full Text Available Fluid and electrolyte status have a significant impact on physical performance and health. Pre-exercise recommendations cite the possibility of consuming beverages with high amounts of sodium. In this sense, non-alcoholic beer can be considered an effective pre-exercise hydration beverage. This double-blind, randomized study aimed to compare the effect of beer, non-alcoholic beer and water consumption before exercise on fluid and electrolyte homeostasis. Seven male soccer players performed 45 min of treadmill running at 65% of the maximal heart rate, 45 min after ingesting 0.7 L of water (W, beer (AB or non-alcoholic beer (NAB. Body mass, plasma Na+ and K+ concentrations and urine specific gravity (USG were assessed before fluid consumption and after exercise. After exercise, body mass decreased (p < 0.05 in W (−1.1%, AB (−1.0% and NAB (−1.0%. In the last minutes of exercise, plasma Na+ was reduced (p < 0.05 in W (−3.9% and AB (−3.7%, plasma K+ was increased (p < 0.05 in AB (8.5%, and USG was reduced in W (−0.9% and NAB (−1.0%. Collectively, these results suggest that non-alcoholic beer before exercise could help maintain electrolyte homeostasis during exercise. Alcoholic beer intake reduced plasma Na+ and increased plasma K+ during exercise, which may negatively affect health and physical performance, and finally, the consumption of water before exercise could induce decreases of Na+ in plasma during exercise.

Computational fluid dynamics modeling of a lithium/thionyl chloride battery with electrolyte flow

Energy Technology Data Exchange (ETDEWEB)

Gu, W.B.; Wang, C.Y.; Weidner, J.W.; Jungst, R.G.; Nagasubramanian, G.

2000-02-01

A two-dimensional model is developed to simulate discharge of a lithium/thionyl chloride primary battery. As in earlier one-dimensional models, the model accounts for transport of species and charge, and electrode porosity variations and electrolyte flow induced by the volume reduction caused by electrochemical reactions. Numerical simulations are performed using a finite volume method of computational fluid dynamics. The predicted discharge curves for various temperatures show good agreement with published experimental data, and are essentially identical to results published for one-dimensional models. The detailed two-dimensional flow simulations show that the electrolyte is replenished from the cell head space predominantly through the separator into the front of the cathode during most parts of the discharge, especially for higher cell temperatures.

The component content of active particles in a plasma-chemical reactor based on volume barrier discharge

Science.gov (United States)

Soloshenko, I. A.; Tsiolko, V. V.; Pogulay, S. S.; Terent'yeva, A. G.; Bazhenov, V. Yu; Shchedrin, A. I.; Ryabtsev, A. V.; Kuzmichev, A. I.

2007-02-01

In this paper the results of theoretical and experimental studies of the component content of active particles formed in a plasma-chemical reactor composed of a multiple-cell generator of active particles, based on volume barrier discharge, and a working chamber are presented. For calculation of the content of uncharged plasma components an approach is proposed which is based on averaging of the power introduced over the entire volume. Advantages of such an approach lie in an absence of fitting parameters, such as the dimensions of microdischarges, their surface density and rate of breakdown. The calculation and the experiment were accomplished with the use of dry air (20% relative humidity) as the plasma generating medium. Concentrations of O3, HNO3, HNO2, N2 O5 and NO3 were measured experimentally in the discharge volume and working chamber for the residence time of particles on a discharge of 0.3 s and more and discharge specific power of 1.5 W cm-3. It has been determined that the best agreement between the calculation and the experiment occurs at calculated gas medium temperatures in the discharge plasma of about 400-425 K, which correspond to the experimentally measured rotational temperature of nitrogen. In most cases the calculated concentrations of O3, HNO3, HNO2, N2O5 and NO3 for the barrier discharge and the working chamber are in fairly good agreement with the respective measured values.

The component content of active particles in a plasma-chemical reactor based on volume barrier discharge

International Nuclear Information System (INIS)

Soloshenko, I A; Tsiolko, V V; Pogulay, S S; Terent'yeva, A G; Bazhenov, V Yu; Shchedrin, A I; Ryabtsev, A V; Kuzmichev, A I

2007-01-01

In this paper the results of theoretical and experimental studies of the component content of active particles formed in a plasma-chemical reactor composed of a multiple-cell generator of active particles, based on volume barrier discharge, and a working chamber are presented. For calculation of the content of uncharged plasma components an approach is proposed which is based on averaging of the power introduced over the entire volume. Advantages of such an approach lie in an absence of fitting parameters, such as the dimensions of microdischarges, their surface density and rate of breakdown. The calculation and the experiment were accomplished with the use of dry air (20% relative humidity) as the plasma generating medium. Concentrations of O 3 , HNO 3 , HNO 2 , N 2 O 5 and NO 3 were measured experimentally in the discharge volume and working chamber for the residence time of particles on a discharge of 0.3 s and more and discharge specific power of 1.5 W cm -3 . It has been determined that the best agreement between the calculation and the experiment occurs at calculated gas medium temperatures in the discharge plasma of about 400-425 K, which correspond to the experimentally measured rotational temperature of nitrogen. In most cases the calculated concentrations of O 3 , HNO 3 , HNO 2 , N 2 O 5 and NO 3 for the barrier discharge and the working chamber are in fairly good agreement with the respective measured values

Physiological adaptation of maternal plasma volume during pregnancy: a systematic review and meta-analysis

NARCIS (Netherlands)

Haas, S.; Ghossein-Doha, C.; Kuijk, S.M. van; Drongelen, J. van; Spaanderman, M.E.A.

2017-01-01

OBJECTIVE: To describe the physiological pattern of gestational plasma volume adjustments in normal singleton pregnancy and compare this with the pattern in pregnancies complicated by pregnancy-induced hypertension, pre-eclampsia or fetal growth restriction. METHODS: We performed a meta-analysis of

Adjustment of the ratio of Ca/P in the ceramic coating on Mg alloy by plasma electrolytic oxidation

International Nuclear Information System (INIS)

Yao Zhongping; Li Liangliang; Jiang Zhaohua

2009-01-01

The ceramic coatings containing Ca and P were prepared on AZ91D Mg alloy by plasma electrolytic oxidation technique in NaOH system and Na 2 SiO 3 system, respectively. The phase composition, morphology and the element distribution of the coatings was studied by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. The corrosion resistance of the coatings was examined by polarizing curve methods in a 0.9% NaCl solution. In NaOH system, there were a large number of micro-holes distributing evenly on the surface of the coating, and the coating was mainly composed of Mg, Al, P and Ca. In Na 2 SiO 3 system, the micro-holes in the coatings were reduced greatly in number and the distribution of the micro-holes was uneven, and the coating was mainly composed of Mg, Al, Si, P and Ca. The ratio of Ca/P in the coating can be controlled by the adjustment of the technique parameters to a certain extent. The adjustment of the concentration of Ca 2+ in the electrolyte was an effective method to change the ratio of Ca/P in the coating in both systems; the reaction time and the working voltage for the adjustment of the ratio of Ca/P in the coating was more suitable for the NaSi 2 O 3 system than the NaOH system. The polarizing curve tests showed the coatings improved the corrosion resistance of the AZ91D Mg alloy in 0.9% NaCl solution by nearly two orders of magnitude.

Electrolytic decontamination of stainless steel using a basic electrolyte

International Nuclear Information System (INIS)

Childs, E.L.; Long, J.L.

1981-01-01

An electrolytic plutonium decontamination process or stainless steel was developed for use as the final step in a proposed radioactive waste handling and decontamination facility to be construced at the Rockwell International Rocky Flats plutonium handling facility. This paper discusses test plan, which was executed to compare the basic electrolyte with phosphoric acid and nitric acid electrolytes. 1 ref

Effects of current density and electrolyte temperature on the volume expansion factor of anodic alumina formed in oxalic acid

International Nuclear Information System (INIS)

Zhou, F.; Baron-Wiecheć, A.; Garcia-Vergara, S.J.; Curioni, M.; Habazaki, H.; Skeldon, P.; Thompson, G.E.

2012-01-01

The formation of porous anodic alumina in 0.4 M oxalic acid is investigated over a range of current density and electrolyte temperature using sputtering-deposited substrates containing tungsten tracer layers. The findings reveal volume expansion factors and efficiencies of film growth that increase with the increase of the current density and decrease of the temperature. Pore generation by the flow of the anodic alumina in the barrier layer toward the pore walls is proposed to dominate at relatively high current densities (above ∼2 mA cm −2 ), with tungsten tracer species being retained within films. Conversely, losses of tungsten species occur at lower current densities, possibly due to increased field-assisted ejection of Al 3+ ions and/or field-assisted dissolution of the anodic alumina.

Study on property-gradient polymer electrolyte for rechargeable lithium batteries; Lithium niji denchi no tame no keisha tokusei kobunshi denkaishitsu no sosei ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Kokumi, Z; Kanemura, S; Inaba, M; Takehara, Z; Yao, K; Uchimoto, Y [Kyoto University, Kyoto (Japan)

1997-02-01

This paper describes the fundamental experiments for creating property-gradient polymer electrolyte for rechargeable lithium batteries. The rechargeable lithium battery is composed of an anodic composite agent section with high ion conductivity, a separator equivalent section with high mechanical strength (high bridging degree), and a section surpressing the precipitation of metal lithium by contacting with it. The continuous property-gradient polymer electrolyte was tried to be synthesized by means of the plasma polymerization method. As a result, plasma polymerization electrolyte with high ion conductivity could be prepared from the liquid phase by using a monomer with low vapor pressure. Porous material simulating the anodic composite agent was impregnated by the monomer, which was plasma-polymerized. As a result, it was found that the bridging degree decreased from the surface towards the inside of the plasma-polymerized porous material. In addition, polymer was prepared using fluorine-base monomer. Thus, LiF thin film could be prepared through the reaction between the polymer and metal lithium. 3 figs.

Effect of a ten-week Nordic Walking exercise program on serum electrolyte concentration and plasma acid-base balance in postmenopausal women with overweight or obesity

OpenAIRE

Kałużny, Krystian; Kałużna, Anna; Budzyński, Jacek; Hagner, Wojciech; Kochański, Bartosz; Żukow, Walery; Bronisz, Agata; Hagner‑Derengowska, Magdalena

2016-01-01

Kałużny Krystian, Kałużna Anna, Budzyński Jacek, Hagner Wojciech, Kochański Bartosz, Żukow Walery, Bronisz Agata, Hagner‑Derengowska Magdalena. Effect of a ten-week Nordic Walking exercise program on serum electrolyte concentration and plasma acid-base balance in postmenopausal women with overweight or obesity. Journal of Education, Health and Sport. 2016;6(12):353-364. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.201929 http://ojs.ukw.edu.pl/index.php/johs/article/view/4065 ...

Highly Quantitative Electrochemical Characterization of Non-Aqueous Electrolytes & Solid Electrolyte Interphases

Energy Technology Data Exchange (ETDEWEB)

Sergiy V. Sazhin; Kevin L. Gering; Mason K. Harrup; Harry W. Rollins

2012-10-01

The methods to measure solid electrolyte interphase (SEI) electrochemical properties and SEI formation capability of non-aqueous electrolyte solutions are not adequately addressed in the literature. And yet, there is a strong demand in new electrolyte generations that promote stabilized SEIs and have an influence to resolve safety, calendar life and other limitations of Li-ion batteries. To fill this gap, in situ electrochemical approach with new descriptive criteria for highly quantitative characterization of SEI and electrolytes is proposed. These criteria are: SEI formation capacity, SEI corrosion rate, SEI maintenance rate, and SEI kinetic stability. These criteria are associated with battery parameters like irreversible capacity, self-discharge, shelf-life, power, etc. Therefore, they are especially useful for electrolyte development and standard fast screening, allowing a skillful approach to narrow down the search for the best electrolyte. The characterization protocol also allows retrieving information on interfacial resistance for SEI layers and the electrochemical window of electrolytes, the other important metrics of characterization. The method validation was done on electrolyte blends containing phosphazenes, developed at Idaho National Laboratory, as 1.2M LiPF6 [80 % EC-MEC (2:8) (v/v) + 20% Phosphazene variety] (v/v), which were targeted for safer electrolyte variations.

Administration of olive oil followed by a low volume of polyethylene glycol-electrolyte lavage solution improves patient satisfaction with right-side colonic cleansing over administration of the conventional volume of polyethylene glycol-electrolyte lavage solution for colonoscopy preparation.

Science.gov (United States)

Abut, Evren; Guveli, Hakan; Yasar, Bulent; Bolukbas, Cengiz; Bolukbas, Filiz Fusun; Ince, Ali Tuzun; Kendir, Tulin; Dalay, Ali Remzi; Kurdas, Oya Ovunc

2009-09-01

Proper bowel cleansing before colonoscopy is essential for satisfactory evaluation of the colon. The required consumption of a large volume of salty-tasting liquid, 4 L of polyethylene glycol-electrolyte lavage solution (PEG-ELS), is the primary limitation to achieving this goal. To achieve better patient satisfaction with efficient bowel cleansing, we compared the effects of the conventional volume (4 L) of PEG-ELS with those of a low volume (2 L) in combination with pretreatment using different laxatives, such as magnesium hydroxide (milk of magnesia) and olive oil. Randomized, controlled study. A single research hospital. Patients undergoing elective colonoscopy. A total of 120 patients were randomized to 1 of 3 different preparation regimens: 39 patients were prepared with a conventional volume (4 L) of PEG-ELS (Preparation [Prep] 1), and the remaining patients were prepared with a lower volume (2 L) of PEG-ELS and pretreatment with a laxative, either 15 g of magnesium hydroxide (40 patients, Prep 2) or 60 mL of olive oil (41 patients, Prep 3) 3 hours before PEG-ELS administration. The primary outcome was the efficacy of colonic cleansing on the left and right sides. Secondary outcomes were patient satisfaction and side effects. The olive oil regimen (Prep 3) resulted in significantly more adequate bowel cleansing of the right colon than administration of the conventional volume of PEG-ELS (Prep 1) and the magnesium hydroxide (Prep 2) regimen (97.6% vs 74.5% and 72.5%, respectively, P = .007). However, this difference was not observed in the left colon (91.5%, 85.5%, and 91.8% for Preps 1, 2, and 3, respectively, P = .776). When asked, 38 patients (95%) taking Prep 2, 35 patients (85.3%) taking Prep 3, and only 11 patients (28.2%) taking Prep 1 preferred the same preparation regimen if they required a future colonoscopy (P =.006), based on ease of use and taste. The side effects were comparable in each group. The limitations of this study include the relatively

A highly conductive, non-flammable polymer–nanoparticle hybrid electrolyte

KAUST Repository

Agrawal, Akanksha

2015-01-01

© 2015 The Royal Society of Chemistry. We report on the physical properties of lithium-ion conducting nanoparticle-polymer hybrid electrolytes created by dispersing bidisperse mixtures of polyethylene glycol (PEG)-functionalized silica nanoparticles in an aprotic liquid host. At high particle contents, we find that the ionic conductivity is a non-monotonic function of the fraction of larger particles xL in the mixtures, and that for the nearly symmetric case xL ≈ 0.5 (i.e. equal volume fraction of small and large particles), the room temperature ionic conductivity is nearly ten-times larger than in similar nanoparticle hybrid electrolytes comprised of the pure small (xL ≈ 0) or large (xL ≈ 1) particle components. Complementary trends are seen in the activation energy for ion migration and effective tortuosity of the electrolytes, which both exhibit minima near xL ≈ 0.5. Characterization of the electrolytes by dynamic rheology reveals that the maximum conductivity coincides with a distinct transition in soft glassy properties from a jammed to partially jammed and back to jammed state, as the fraction of large particles is increased from 0 to 1. This finding implies that the conductivity enhancement arises from purely entropic loss of correlation between nanoparticle centers arising from particle size dispersity. As a consequence of these physics, it is now possible to create hybrid electrolytes with MPa elastic moduli and mS cm-1 ionic conductivity levels at room temperature using common aprotic liquid media as the electrolyte solvent. Remarkably, we also find that even in highly flammable liquid media, the bidisperse nanoparticle hybrid electrolytes can be formulated to exhibit low or no flammability without compromising their favorable room temperature ionic conductivity and mechanical properties.

effects of artemether on the plasma and urine concentrations of ...

African Journals Online (AJOL)

Dr Komolafe

2011-05-16

May 16, 2011 ... degeneration of the renal tissue of rats, inability of the damaged kidneys to concentrate urine, which manifested as excessive water loss and electrolyte depletion. Key words: Artemether, electrolytes in plasma, urine concentrations, rats. INTRODUCTION. Artemether, one of the derivatives of artemisinin, is.

Experience in therapeutic plasma exchange by membrane filtration at an academic center in Colombia: Registry of the first 500 sessions.

Science.gov (United States)

Córdoba, Juan Pablo; Larrarte, Carolina; Medina, María Camila

2015-12-01

Therapeutic plasma exchange (TPE) is an extracorporeal blood purification therapy that is part of the treatment of various diseases. Plasma and blood cells can be separated by centrifugation or using membrane separators. A descriptive analysis, in which the first 500 TPE sessions using membrane filtration without anticoagulation of the extracorporeal circuit are described. Five hundred (500) TPE sessions were performed on 68 patients over a period of 5 years. Therapeutic indications were 17 different diseases. 5% albumin was the most frequent replacement solution used in 62% of sessions. The mean number of plasma volume replacements was 1.33. Complications occurred in 7.6% of the sessions. Arterial hypotension was the most common event and clotting of the extracorporeal circuit was documented in just one TPE session. Electrolyte tests performed in patients during the procedure showed: 11% hypocalcemia, with a similar distribution of hypokalemia. Twenty-two percent (22%) and 37% of phosphorus and magnesium records, respectively, were higher than normal. No symptoms associated with electrolyte abnormalities were documented. TPE by membrane filtration is one of the techniques by which it is possible to perform such therapy. In this registry, a low rate of complications was documented. While the need for anticoagulation may be related not only to clotting of the circuit but also to the efficiency of the therapy, clinical response in this series of patients was as expected for each disease. Continuous monitoring and an individualized analysis of electrolytes should be performed in TPE patients. © 2015 Wiley Periodicals, Inc.

Development of volume-reduction system for ion exchange resin using inductively coupled plasma

International Nuclear Information System (INIS)

Fujisawa, Morio; Katagiri, Genichi

2002-01-01

The spent ion exchange resin generated as radioactive waste in water purifying system at nuclear power stations or related facilities of nuclear power has been stored in the site, and its volume has been increasing year by year. We had developed a full-scale system of IC plasma volume-reduction system for the spent resin, and have performed basic performance test using some samples imitating the spent resin. As the results, the imitation of the resin can be reduced in volume by more than 90% so that the processing performance in actual scale was proved to be effective. In addition, it was clarified that the residuum after volume-reduction process is easy to mix with cement, and solidity containing 30wt% residuum provides high strength of 68 MPa. Therefore, we evaluate the application of this process to stabilization of the disposal to be very effective. (author)

Electrical method for the measurements of volume averaged electron density and effective coupled power to the plasma bulk

Science.gov (United States)

Henault, M.; Wattieaux, G.; Lecas, T.; Renouard, J. P.; Boufendi, L.

2016-02-01

Nanoparticles growing or injected in a low pressure cold plasma generated by a radiofrequency capacitively coupled capacitive discharge induce strong modifications in the electrical parameters of both plasma and discharge. In this paper, a non-intrusive method, based on the measurement of the plasma impedance, is used to determine the volume averaged electron density and effective coupled power to the plasma bulk. Good agreements are found when the results are compared to those given by other well-known and established methods.

Investigation of Obtaining Highly-Strong Wire of 12X18H10T-Steei by Drawing Method with Electrolyte-Plasma Surface Machining

Directory of Open Access Journals (Sweden)

L. A. Isaevich

2005-01-01

Full Text Available Purpose of the paper is to investigate technology of strain hardening of corrosion-resistant austenitic 12X18H10T steel by drawing method using electrolyte-plasma machining (EPM as an auxiliary operation. Structure and properties of material surface layer after drawing have been examined. It has been ascertained that there are scores and micro-cracks on the material surface that make it difficult to carry out subsequent drawing drafts.In order to eliminate these drawbacks it is proposed to apply EPM between drawing stages. The developed drawing modes using EPM allow to reduce number of drafts while obtaining special hard- drawn wire and improve service life of the tool.

Plasma Electrolytic Oxidation of Titanium Implant Surfaces: Microgroove-Structures Improve Cellular Adhesion and Viability.

Science.gov (United States)

Hartjen, Philip; Hoffmann, Alexia; Henningsen, Anders; Barbeck, Mike; Kopp, Alexander; Kluwe, Lan; Precht, Clarissa; Quatela, Olivia; Gaudin, Robert; Heiland, Max; Friedrich, Reinhard E; Knipfer, Christian; Grubeanu, Daniel; Smeets, Ralf; Jung, Ole

2018-01-01

Plasma electrolytic oxidation (PEO) is an established electrochemical treatment technique that can be used for surface modifications of metal implants. In this study we to treated titanium implants with PEO, to examine the resulting microstructure and to characterize adhesion and viability of cells on the treated surfaces. Our aim was to identify an optimal surface-modification for titanium implants in order to improve soft-tissue integration. Three surface-variants were generated on titanium alloy Ti6Al4V by PEO-treatment. The elemental composition and the microstructures of the surfaces were characterized using energy dispersive X-ray spectroscopy, scanning electron microscopy and profilometry. In vitro cytocompatibility of the surfaces was assessed by seeding L929 fibroblasts onto them and measuring the adhesion, viability and cytotoxicity of cells by means of live/dead staining, XTT assay and LDH assay. Electron microscopy and profilometry revealed that the PEO-surface variants differed largely in microstructure/topography, porosity and roughness from the untreated control material as well as from one another. Roughness was generally increased after PEO-treatment. In vitro, PEO-treatment led to improved cellular adhesion and viability of cells accompanied by decreased cytotoxicity. PEO-treatment provides a promising strategy to improve the integration of titanium implants with surrounding tissues. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Surface characterization and corrosion behavior of calcium phosphate-base composite layer on titanium and its alloys via plasma electrolytic oxidation: A review paper.

Science.gov (United States)

Rafieerad, A R; Ashra, M R; Mahmoodian, R; Bushroa, A R

2015-12-01

In recent years, calcium phosphate-base composites, such as hydroxyapatite (HA) and carbonate apatite (CA) have been considered desirable and biocompatible coating layers in clinical and biomedical applications such as implants because of the high resistance of the composites. This review focuses on the effects of voltage, time and electrolytes on a calcium phosphate-base composite layer in case of pure titanium and other biomedical grade titanium alloys via the plasma electrolytic oxidation (PEO) method. Remarkably, these parameters changed the structure, morphology, pH, thickness and crystallinity of the obtained coating for various engineering and biomedical applications. Hence, the structured layer caused improvement of the biocompatibility, corrosion resistance and assignment of extra benefits for Osseo integration. The fabricated layer with a thickness range of 10 to 20 μm was evaluated for physical, chemical, mechanical and tribological characteristics via XRD, FESEM, EDS, EIS and corrosion analysis respectively, to determine the effects of the applied parameters and various electrolytes on morphology and phase transition. Moreover, it was observed that during PEO, the concentration of calcium, phosphor and titanium shifts upward, which leads to an enhanced bioactivity by altering the thickness. The results confirm that the crystallinity, thickness and contents of composite layer can be changed by applying thermal treatments. The corrosion behavior was investigated via the potentiodynamic polarization test in a body-simulated environment. Here, the optimum corrosion resistance was obtained for the coating process condition at 500 V for 15 min in Ringer solution. This review has been summarized, aiming at the further development of PEO by producing more adequate titanium-base implants along with desired mechanical and biomedical features. Copyright © 2015 Elsevier B.V. All rights reserved.

Process automation system for integration and operation of Large Volume Plasma Device

International Nuclear Information System (INIS)

Sugandhi, R.; Srivastava, P.K.; Sanyasi, A.K.; Srivastav, Prabhakar; Awasthi, L.M.; Mattoo, S.K.

2016-01-01

Highlights: • Analysis and design of process automation system for Large Volume Plasma Device (LVPD). • Data flow modeling for process model development. • Modbus based data communication and interfacing. • Interface software development for subsystem control in LabVIEW. - Abstract: Large Volume Plasma Device (LVPD) has been successfully contributing towards understanding of the plasma turbulence driven by Electron Temperature Gradient (ETG), considered as a major contributor for the plasma loss in the fusion devices. Large size of the device imposes certain difficulties in the operation, such as access of the diagnostics, manual control of subsystems and large number of signals monitoring etc. To achieve integrated operation of the machine, automation is essential for the enhanced performance and operational efficiency. Recently, the machine is undergoing major upgradation for the new physics experiments. The new operation and control system consists of following: (1) PXIe based fast data acquisition system for the equipped diagnostics; (2) Modbus based Process Automation System (PAS) for the subsystem controls and (3) Data Utilization System (DUS) for efficient storage, processing and retrieval of the acquired data. In the ongoing development, data flow model of the machine’s operation has been developed. As a proof of concept, following two subsystems have been successfully integrated: (1) Filament Power Supply (FPS) for the heating of W- filaments based plasma source and (2) Probe Positioning System (PPS) for control of 12 number of linear probe drives for a travel length of 100 cm. The process model of the vacuum production system has been prepared and validated against acquired pressure data. In the next upgrade, all the subsystems of the machine will be integrated in a systematic manner. The automation backbone is based on 4-wire multi-drop serial interface (RS485) using Modbus communication protocol. Software is developed on LabVIEW platform using

Process automation system for integration and operation of Large Volume Plasma Device

Energy Technology Data Exchange (ETDEWEB)

Sugandhi, R., E-mail: ritesh@ipr.res.in; Srivastava, P.K.; Sanyasi, A.K.; Srivastav, Prabhakar; Awasthi, L.M.; Mattoo, S.K.

2016-11-15

Highlights: • Analysis and design of process automation system for Large Volume Plasma Device (LVPD). • Data flow modeling for process model development. • Modbus based data communication and interfacing. • Interface software development for subsystem control in LabVIEW. - Abstract: Large Volume Plasma Device (LVPD) has been successfully contributing towards understanding of the plasma turbulence driven by Electron Temperature Gradient (ETG), considered as a major contributor for the plasma loss in the fusion devices. Large size of the device imposes certain difficulties in the operation, such as access of the diagnostics, manual control of subsystems and large number of signals monitoring etc. To achieve integrated operation of the machine, automation is essential for the enhanced performance and operational efficiency. Recently, the machine is undergoing major upgradation for the new physics experiments. The new operation and control system consists of following: (1) PXIe based fast data acquisition system for the equipped diagnostics; (2) Modbus based Process Automation System (PAS) for the subsystem controls and (3) Data Utilization System (DUS) for efficient storage, processing and retrieval of the acquired data. In the ongoing development, data flow model of the machine’s operation has been developed. As a proof of concept, following two subsystems have been successfully integrated: (1) Filament Power Supply (FPS) for the heating of W- filaments based plasma source and (2) Probe Positioning System (PPS) for control of 12 number of linear probe drives for a travel length of 100 cm. The process model of the vacuum production system has been prepared and validated against acquired pressure data. In the next upgrade, all the subsystems of the machine will be integrated in a systematic manner. The automation backbone is based on 4-wire multi-drop serial interface (RS485) using Modbus communication protocol. Software is developed on LabVIEW platform using

Contrast media osmolality and plasma volume changes

International Nuclear Information System (INIS)

Hine, A.L.; Lui, D.; Dawson, P.; Middlesex Hospital, London

1985-01-01

A theoretical and experimental study of the plasma volume expansion consequent on the hyperosmolality of contrast media is presented. In the case of the ratio 1.5 media theory and experiment coincide closely but in the case of the ratio 3 media the observed changes exceed the predicted. It is proposed that this is due partly to the slower diffusion of the ratio 3 media out of the intravascular space and partly due to the fact that the osmotic load presented by these media is greater than would be expected from a study of their commercial solutions in which osmolality is reduced by molecular aggregation. The implications for the relative haemodynamic effects of different contrast media are discussed. The osmotic effects of contrast media also play a part in determining the image quality achievable in intravenous digital subtraction angiography (IV-DSA). It is predicted that ratio 3 contrast media will give better quality images in IV-DSA than ratio 1.5 media. (orig.)

The Blood Volume of the Guinea Pig: Effects of Epinephrine and Isoproterenol upon the Red Cell and Plasma Volumes, Heart Rate, and Mean Arterial Pressure,

Science.gov (United States)

1987-09-01

capillaries (4), blood volumes calculated from plasma volume measures must correct for label that has left the system between the time of the injected dose...Splenic sequestration and contraction are mediated by the autonomic nervous system and blood-borne agents (10). Sympathetic nerve fibers from the truncus...sympathlcus and parasympathetic neurons of the nervus vagus (cranial nerve X) innervate the celiac plexus (8, 11). A subdivision of the celiac plexus

Electrochemical and biological characterization of coatings formed on Ti-15Mo alloy by plasma electrolytic oxidation.

Science.gov (United States)

Kazek-Kęsik, Alicja; Krok-Borkowicz, Małgorzata; Pamuła, Elżbieta; Simka, Wojciech

2014-10-01

β-Type titanium alloys are considered the future materials for bone implants. To improve the bioactivity of Ti-15Mo, the surface was modified using the plasma electrolytic oxidation (PEO) process. Tricalcium phosphate (TCP, Ca3PO4), wollastonite (CaSiO3) and silica (SiO2) were selected as additives in the anodizing bath to enhance the bioactivity of the coatings formed during the PEO process. Electrochemical analysis of the samples was performed in Ringer's solution at 37°C. The open-circuit potential (EOCP) as a function of time, corrosion potential (ECORR), corrosion current density (jCORR) and polarization resistance (Rp) of the samples were determined. Surface modification improved the corrosion resistance of Ti-15Mo in Ringer's solution. In vitro studies with MG-63 osteoblast-like cells were performed for 1, 3 and 7 days. After 24h, the cells were well adhered on the entire surfaces, and their number increased with increasing culture time. The coatings formed in basic solution with wollastonite exhibited better biological performance compared with the as-ground sample. Copyright © 2014 Elsevier B.V. All rights reserved.

Electrochemical Impedance and Polarization Corrosion Studies of Tantalum Surface Modified by DC Plasma Electrolytic Oxidation

Directory of Open Access Journals (Sweden)

Maciej Sowa

2018-04-01

Full Text Available Tantalum has recently become an actively researched biomaterial for the bone reconstruction applications because of its excellent corrosion resistance and successful clinical records. However, a bare Ta surface is not capable of directly bonding to the bone upon implantation and requires some method of bioactivation. In this study, this was realized by direct current (DC plasma electrolytic oxidation (PEO. Susceptibility to corrosion is a major factor determining the service-life of an implant. Therefore, herein, the corrosion resistance of the PEO coatings on Ta was investigated in Ringer’s solution. The coatings were formed by galvanostatic anodization up to 200, 300 and 400 V, after which the treatment was conducted potentiostatically until the total process time amounted to 5 min. Three solutions containing Ca(H2PO22, Ca(HCOO2 and Mg(CH3COO2 were used in the treatment. For the corrosion characterization, electrochemical impedance spectroscopy and potentiodynamic polarization techniques were chosen. The coatings showed the best corrosion resistance at voltages low enough so that the intensive sparking was absent, which resulted in the formation of thin films. The impedance data were fitted to the equivalent electrical circuits with two time constants, namely R(Q[R(QR] and R(Q[R(Q[RW

Physicochemical properties of the electrolyte system lithium tetrachloraluminate(III)-thionyl chloride

Energy Technology Data Exchange (ETDEWEB)

Demakhin, A.G.; Kuznetsov, N.N.

1992-07-20

The solubility of lithium chloroaluminate in thionyl chloride has been determined over the temperature range 233-323 K. The composition of solid phases in equilibrium with saturated solution was found. The density, viscosity, and electrical conductance of lithium chloroaluminate solutions in thionyl chloride were determined over the temperature range 263-333 K and pseudomolar volumes of the solution and apparent molar volumes of the electrolyte calculated. Activation energies for viscous flow and conductance have been calculated. 12 refs., 5 figs., 1 tab.

Proceedings of the international symposium on environmental technologies: Plasma systems and applications. Volume 1

International Nuclear Information System (INIS)

Mayne, P.W.; Mulholland, J.A.

1995-01-01

Plasma technology is an extremely versatile and powerful means of obtaining very high temperatures that can be used in a variety of environmental situations. Since most types of waste products and contaminants can be treated effectively and efficiently, plasma systems have been developed to address the disposal and annihilation domestic of medical, hazardous, radioactive, military, and miscellaneous wastes. Plasma technologies can also be implemented to recycle and recover usable materials from metallic wastes. The International Symposium on Environmental Technologies: Plasma Systems and Applications was held at the Omni Hotel in Atlanta, Georgia on October 8--12, 1995 to bring together a large group of technical experts working on the use of plasma for solving environmental problems. The Symposium is a sequel to the 1994 Metatechnies Conference on Stabilization and Volarization of Ultimate Waste by Plasma Processes that was held in September of 1994 at Bordeaux Lac, France. The proceedings to this second international conference contain the written contributions from eleven sessions and are published in two volumes. A total of 65 papers address the use of plasma systems for environmental applications and include topics concerning the development and use of innovative technologies for waste treatment, environmental remediation, recycling, characterization of the plasma and solid residue, off-gas analyses, as well as case studies and regulatory policies

Electrolytic gettering of tritium from air

International Nuclear Information System (INIS)

Souers, P.C.; Tsugawa, R.T.; Stevens, C.G.

1983-01-01

We have removed 90% of 1 part-per-million tritium gas in air of 25% to 35% humidity by the dc electrical action of the solid proton electrolyte hydrogen uranyl phosphate (HUP). Gettering takes 5 to 24 hours for a 1 cm 2 HUP disc at 2 to 4 V in a static, 1200 cc gas volume. Hydrogen gas may be used to flush captured tritium through the HUP. Liquid water leaches out the tritium but water vapor is ineffective. This technique promises an alternative to the conventional catalyst/zeolite method

Identification of lysophosphatidylcholine, γ-stearoyl (LPCD) as an endogenous Na+, K+-ATPase inhibitor in volume-expanded hog plasma

International Nuclear Information System (INIS)

Tamura, M.; Inagami, T.

1986-01-01

We have shown that the Na + , K + -ATPase inhibitory activities in the plasma of volume-expanded hog consist of multiple components. One group of the major inhibitory activities induced by intravascular saline infusion was identified as unsaturated free fatty acids. The present study was undertaken to determine the identity of the remaining Na + , K + -ATPase inhibitory activity in the plasma of volume-expanded hogs. Three peaks with ouabain displacing activity (ODA) were separated by HPLC on a reversed phase octadecyl column. The slowest eluting material which showed good solubility in water and recognizable optical absorbance at 214 nm was purified further by three additional steps of reverse phase HPLC. FAB mass spectrometry and 1 H NMR spectroscopy identified this substance as lysophosphatidylcholine, γ-stearoyl. Both purified and synthetic LPCS showed dose-dependent inhibition of Na + , K + -ATPase and displacement of [ 3 H] ouabain from the ATPase. Lysophosphatidylcholines containing either palmitoyl or myristoyl groups also exhibited the Na + , K + -ATPase inhibitory activity and the ODA. The ODA in the LPCS containing fraction increased during the saline infusion. These results indicate that LPCS is an endogenous Na + , K + -ATPase inhibitor which is induced by the expansion of plasma volume

Quantitative Analysis of Oxygen Gas Exhausted from Anode through In Situ Measurement during Electrolytic Reduction

Directory of Open Access Journals (Sweden)

Eun-Young Choi

2017-01-01

Full Text Available Quantitative analysis by in situ measurement of oxygen gas evolved from an anode was employed to monitor the progress of electrolytic reduction of simulated oxide fuel in a molten Li2O–LiCl salt. The electrolytic reduction of 0.6 kg of simulated oxide fuel was performed in 5 kg of 1.5 wt.% Li2O–LiCl molten salt at 650°C. Porous cylindrical pellets of simulated oxide fuel were used as the cathode by loading a stainless steel wire mesh cathode basket. A platinum plate was employed as the anode. The oxygen gas evolved from the anode was exhausted to the instrumentation for in situ measurement during electrolytic reduction. The instrumentation consisted of a mass flow controller, pump, wet gas meter, and oxygen gas sensor. The oxygen gas was successfully measured using the instrumentation in real time. The measured volume of the oxygen gas was comparable to the theoretically calculated volume generated by the charge applied to the simulated oxide fuel.

Analysis of red cell mass and plasma volume in patients with polycythemia vera

International Nuclear Information System (INIS)

Nikolova, K.; Vassileva, D.

2006-01-01

Full text: Polycythemia vera (PV) was first described in 1892. The primary objective during the evaluation of erythrocytosis is to ascertain the presence or absence of PV. Because of prognostic and treatment differences, PV must be distinguished from relative polycythemia and secondary erythrocytosis. A retrospective analysis of RCM and plasma volume data are presented with special attention to different methods of RCM interpretation. A total 104 patients was studied (26 women and 78 men). Measurements of RCM and plasma volume were performed using chromium-51 labeled red cells. Results were expressed in millilitres by using the actual patient weight and using body surface area. There was a high prevalence of overweight or obesity in our population. However adipose tissue is relatively avascular, can lack precision of measurement of RCM in obese individuals. Pearson et al. showed that the results from 98% of males and 99% of females fall between ± 25% of the mean value at any given surface area. Using these limits as the reference range, we accepted the diagnosis of absolute erythrocytosis when an individual measured RCM is more than 25% above their predicted value

Electrolyte management considerations in modern nickel/hydrogen and nickel/cadmium cells and battery designs

Energy Technology Data Exchange (ETDEWEB)

Thaller, L.H. [The Aerospace Corporation, El Segundo, CA (United States); Zimmermann, A.H. [The Aerospace Corporation, El Segundo, CA (United States)

1996-11-01

While attention has been paid to understanding and modeling abnormal nickel/hydrogen cell behaviors, not enough attention has been paid to the potassium ion content in these cells, and more recently, in batteries. This paper will review three general areas where the potassium ion content can impact the performance and life of nickel/hydrogen and nickel/cadmium cells. Sample calculations of the concentration or volume changes that can take place within operating cells will be presented. With the aid of an accurate model of an operating cell or battery, the impact of changes of potassium ion content within a potential cell design can be estimated. All three of these areas are directly related to the volume tolerance and pore size engineering aspects of the components used in the cell or battery design. the three areas follow. (i) The gamma phase uptake of potassium ion can result in a lowering of the electrolyte concentration. This leads to a higher electrolyte resistance as well as electrolyte diffusional limitations on the discharge rate. This phenomenon also impacts the response of the cell to a reconditioning cycle. (ii) The transport of water vapor from a warmer to a cooler portion of the cell or battery under the driving force of a vapor pressure gradient has already impacted cells when water vapor condenses on a colder cell wall. This paper will explore the convective and diffusive movement of gases saturated with water vapor from a warmer plate pack to a cooler one, both with and without liquid communication. (iii) The impact of low level shunt currents in multicell configurations results in the net movement of potassium hydroxide from one part of the battery to another. This movement impacts the electrolyte volume/vapor pressure relationship within the cell or battery. (orig.)

Renal function and plasma volume following ultramarathon cycling.

Science.gov (United States)

Neumayr, G; Pfister, R; Hoertnagl, H; Mitterbauer, G; Prokop, W; Joannidis, M

2005-01-01

In recreational cyclists marathon cycling influences renal function only on a minimal scale. Respective information on extreme ultramarathon cycling in better trained athletes is not available. The objective was to evaluate the renal and haematological effects of ultraendurance cycling in the world's best ultramarathon cyclists. Creatinine (CR), urea, haemoglobin (Hb), haematocrit (Hct) and plasma volume (PV) were investigated in 16 male ultramarathon cyclists during the 1st Race Across the Alps in 2001 (distance: 525 km; cumulative altitude difference: 12,600 m). All renal functional parameters were normal pre-exercise. During the race serum CR, urea and uric acid rose significantly by 33, 97 % and 18 % (p training kilometers. The serum urea/CR ratio rose above 40 in 12 athletes (75 %). Mean fractional sodium excretion and fractional uric acid excretion fell below 0.5 % (p 0.40; p training.

Severe Leptospirosis with Multiple Organ Failure Successfully Treated by Plasma Exchange and High-Volume Hemofiltration

Directory of Open Access Journals (Sweden)

Vincent Bourquin

2011-01-01

Full Text Available Background. Leptospirosis is a spirochetal zoonosis with complex clinical features including renal and liver failure. Case report. We report the case of a Swiss fisherman presenting with leptospirosis. After initial improvement, refractory septic shock and severe liver and kidney failure developed. The expected mortality was estimated at 90% with clinical scores. The patient underwent plasma exchanges and high-volume hemofiltration (HVHF with complete recovery of hepatic and kidney functions. Discussion. Plasma exchanges and HVHF may confer survival benefit on patients with severe leptospirosis, refractory septic shock, and multiple-organ failure.

Pseudo one-dimensional analysis of polymer electrolyte fuel cell cold-start

Energy Technology Data Exchange (ETDEWEB)

Mukherjee, Partha P [Los Alamos National Laboratory; Mukundan, Rangachary [Los Alamos National Laboratory; Borup, Rodney L [Los Alamos National Laboratory; Wang, Yun [NON LANL; Mishlera, Jeff [NON LANL

2009-01-01

This paper investigates the electrochemical kinetics, oxygen transport, and solid water formation in polymer electrolyte fuel cell (PEFC) during cold start. Following [Yo Wang, J. Electrochem. Soc., 154 (2007) B1041-B1048], we develop a pseudo one-dimensional analysis, which enables the evaluation of the impact of ice volume fraction and temperature variations on cell performance during cold-start. The oxygen profile, starvation ice volume fraction, and relevant overpotentials are obtained. This study is valuable for studying the characteristics of PEFC cold-start.

Large volume serial section tomography by Xe Plasma FIB dual beam microscopy

International Nuclear Information System (INIS)

Burnett, T.L.; Kelley, R.; Winiarski, B.; Contreras, L.; Daly, M.; Gholinia, A.; Burke, M.G.; Withers, P.J.

2016-01-01

Ga + Focused Ion Beam-Scanning Electron Microscopes (FIB-SEM) have revolutionised the level of microstructural information that can be recovered in 3D by block face serial section tomography (SST), as well as enabling the site-specific removal of smaller regions for subsequent transmission electron microscope (TEM) examination. However, Ga + FIB material removal rates limit the volumes and depths that can be probed to dimensions in the tens of microns range. Emerging Xe + Plasma Focused Ion Beam-Scanning Electron Microscope (PFIB-SEM) systems promise faster removal rates. Here we examine the potential of the method for large volume serial section tomography as applied to bainitic steel and WC–Co hard metals. Our studies demonstrate that with careful control of milling parameters precise automated serial sectioning can be achieved with low levels of milling artefacts at removal rates some 60× faster. Volumes that are hundreds of microns in dimension have been collected using fully automated SST routines in feasible timescales (<24 h) showing good grain orientation contrast and capturing microstructural features at the tens of nanometres to the tens of microns scale. Accompanying electron back scattered diffraction (EBSD) maps show high indexing rates suggesting low levels of surface damage. Further, under high current Ga + FIB milling WC–Co is prone to amorphisation of WC surface layers and phase transformation of the Co phase, neither of which have been observed at PFIB currents as high as 60 nA at 30 kV. Xe + PFIB dual beam microscopes promise to radically extend our capability for 3D tomography, 3D EDX, 3D EBSD as well as correlative tomography. - Highlights: • The uptake of dual beam FIBs has been rapid but long milling times have limited imaged volumes to tens of micron dimensions. • Emerging plasma Xe + PFIB-SEM technology offers materials removal rates at least 60× greater than conventional Ga + FIB systems with comparable or less damage. • The

STUDY OF SERUM ELECTROLYTES IN FEMALE THYROID PATIENTS : A CASE CONTROL STUDY

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Neela Mannangi

2015-02-01

women suggests that estrogen might be involved in the pathophysiology of thyroid dysfunction. In our study the serum sodium levels were markedly decreased as compared to healthy controls. According to Saruta T et al Plasma Renin Activity (PRA and Plasma Aldosterone (PA may be suppressed in hypothyroidism probably due to dysfunction of juxtaglomerular cells and glomerul osa cells respectively. The suppression of PRA and PA in patients with hypothyroidism is related to exaggerated sodium excretion and decrease in potassium excretion. CONCLUSION : We conclude that significant decreased Na + and increased K + levels were seen in female hypothyroid patients compared to controls. Hence monitoring of serum levels of these electrolytes will be helpful during the management of hypothyroid patient

Development of volume reduction treatment techniques for low level radioactive wastes

International Nuclear Information System (INIS)

Nabatame, Yasuzi

1984-01-01

The solid wastes packed in drums are preserved in the stores of nuclear establishments in Japan, and the quantity of preservation has already reached about 60 % of the capacity. It has become an important subject to reduce the quantity of generation of radioactive wastes and how to reduce the volume of generated wastes. As the result of the research aiming at the development of the solidified bodies which are excellent in the effect of volume reduction and physical properties, it was confirmed that the plastic solidified bodies using thermosetting resin were superior to conventional cement or asphalt solidification. The plastic solidifying system can treat various radioactive wastes. After radioactive wastes are dried and powdered, they are solidified with plastics, therefore, the effect of volume reduction is excellent. The specific gravity, strength and the resistance to water, fire and radiation were confirmed to be satisfacotory. The plastic solidifying system comprises three subsystems, that is, drying system, powder storing and supplying system and plastic solidifying system. Also the granulation technique after drying and powdering, acid decomposition technique, the microwave melting and solidifying technique for incineration ash, plasma melting process and electrolytic polishing decontamination are described. (Kako, I.)

Plasma diagnostics package. Volume 2: Spacelab 2 section. Part B: Thesis projects

Science.gov (United States)

Pickett, Jolene S. (Compiler); Frank, L. A. (Compiler); Kurth, W. S. (Compiler)

1988-01-01

This volume (2), which consists of two parts (A and B), of the Plasma Diagnostics Package (PDP) Final Science Report contains a summary of all of the data reduction and scientific analyses which were performed using PDP data obtained on STS-51F as a part of the Spacelab 2 (SL-2) payload. This work was performed during the period of launch, July 29, 1985, through June 30, 1988. During this period the primary data reduction effort consisted of processing summary plots of the data received by 12 of the 14 instruments located on the PDP and submitting these data to the National Space Science Data Center (NSSDC). Three Master's and three Ph.D. theses were written using PDP instrumentation data. These theses are listed in Volume 2, Part B.

Water, electrolytes, vitamins and trace elements – Guidelines on Parenteral Nutrition, Chapter 7

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Working group for developing the guidelines for parenteral nutrition of The German Association for Nutritional Medicine

2009-11-01

Full Text Available A close cooperation between medical teams is necessary when calculating the fluid intake of parenterally fed patients. Fluids supplied parenterally, orally and enterally, other infusions, and additional fluid losses (e.g. diarrhea must be considered. Targeted diagnostic monitoring (volume status is required in patients with disturbed water or electrolyte balance. Fluid requirements of adults with normal hydration status is approximately 30–40 ml/kg body weight/d, but fluid needs usually increase during fever. Serum electrolyte concentrations should be determined prior to PN, and patients with normal fluid and electrolyte balance should receive intakes follwing standard recommendations with PN. Additional requirements should usually be administered via separate infusion pumps. Concentrated potassium (1 mval/ml or 20% NaCl solutions should be infused via a central venous catheter. Electrolyte intake should be adjusted according to the results of regular laboratory analyses. Individual determination of electrolyte intake is required when electrolyte balance is initially altered (e.g. due to chronic diarrhea, recurring vomiting, renal insufficiency etc.. Vitamins and trace elements should be generally substituted in PN, unless there are contraindications. The supplementation of vitamins and trace elements is obligatory after a PN of >1 week. A standard dosage of vitamins and trace elements based on current dietary reference intakes for oral feeding is generally recommended unless certain clinical situations require other intakes.

Carbohydrate Electrolyte Solutions Enhance Endurance Capacity in Active Females

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Feng-Hua Sun

2015-05-01

Full Text Available The purpose of the present study was to investigate the effects of supplementation with a carbohydrate-electrolyte solution (CES in active females during a prolonged session of submaximal running to exhaustion. Eight healthy active females volunteered to perform a session of open-ended running to exhaustion at 70% of their maximal oxygen consumption on a treadmill during the follicular phase of their menstrual cycle on two occasions. During each run, the subjects consumed either 3mL·kg−1 body mass of a 6% CES or a placebo drink (PL every 20 min during exercise. The trials were administered in a randomized double-blind, cross-over design. During the run, the subjects ingested similar volumes of fluid in two trials (CES: 644 ± 75 mL vs. PL: 593 ± 66 mL, p > 0.05. The time to exhaustion was 16% longer during the CES trial (106.2 ± 9.4 min than during the PL trial (91.6 ± 5.9 min (p < 0.05. At 45 min during exercise, the plasma glucose concentration in the CES trial was higher than that in PL trial. No differences were observed in the plasma lactate level, respiratory exchange ratio, heart rate, perceived rate of exertion, sensation of thirst, or abdominal discomfort between the two trials (p > 0.05. The results of the present study confirm that CES supplementation improves the moderate intensity endurance capacity of active females during the follicular phases of the menstrual cycle. However, the exogenous oxidation of carbohydrate does not seem to explain the improved capacity after CES supplementation.

Application of electrochemical plasma techniques in surface engineering of iron based structural materials

International Nuclear Information System (INIS)

Coaca, E.; Rusu, O.; Mihalache, M.; Minca, M.; Tacica, M.; Florea, S.; Oncioiu, G.; Andrei, V.

2013-01-01

The surface of austenitic stainless steels 304 L and 316 L was modified by various complex surface treatments: - plasma electrolytic carbo-nitriding by means of Plasma electrolytic saturation (PES); the saturation of cathodic surfaces with C, N was performed using suitable electrolytes (aqueous solutions of inorganic acids, appropriate salts containing the desired elements and certain organic compounds); -electrodeposition of Al from ChCl based Ionic Liquid. The coatings obtained in various experimental conditions have been investigated by means of electron spectroscopy, scanning electron microscopy, energy dispersion x-ray spectrometry, electrochemical techniques, and the properties of the thin films have been correlated with the microstructure and the composition of the surface layers which are strongly dependents of the different regimes of diffusion treatments. The preliminary results on Electrochemical Plasma Technology (EPT) treatments demonstrate that we can select the processing parameters for essential improvement of corrosion behaviour in some aggressive medium and high values of microhardness. (authors)

Neurologic complications of electrolyte disturbances and acid-base balance.

Science.gov (United States)

Espay, Alberto J

2014-01-01

Electrolyte and acid-base disturbances are common occurrences in daily clinical practice. Although these abnormalities can be readily ascertained from routine laboratory findings, only specific clinical correlates may attest as to their significance. Among a wide phenotypic spectrum, acute electrolyte and acid-base disturbances may affect the peripheral nervous system as arreflexic weakness (hypermagnesemia, hyperkalemia, and hypophosphatemia), the central nervous system as epileptic encephalopathies (hypomagnesemia, dysnatremias, and hypocalcemia), or both as a mixture of encephalopathy and weakness or paresthesias (hypocalcemia, alkalosis). Disabling complications may develop not only when these derangements are overlooked and left untreated (e.g., visual loss from intracranial hypertension in respiratory or metabolic acidosis; quadriplegia with respiratory insufficiency in hypermagnesemia) but also when they are inappropriately managed (e.g., central pontine myelinolisis when rapidly correcting hyponatremia; cardiac arrhythmias when aggressively correcting hypo- or hyperkalemia). Therefore prompt identification of the specific neurometabolic syndromes is critical to correct the causative electrolyte or acid-base disturbances and prevent permanent central or peripheral nervous system injury. This chapter reviews the pathophysiology, clinical investigations, clinical phenotypes, and current management strategies in disorders resulting from alterations in the plasma concentration of sodium, potassium, calcium, magnesium, and phosphorus as well as from acidemia and alkalemia. © 2014 Elsevier B.V. All rights reserved.

Effect of strong electrolytes on edible oils part III: viscosity of canola ...

African Journals Online (AJOL)

... in the positive values of B-coefficient. Fluidity parameters were also evaluated and the change in these values with temperature and concentration of oil shows that the electrolytes behave as structure breaker. The energy of activation, latent heat of vaporization and molar volume of oil were also evaluated and discussed.

Study of scattering cross section of a plasma column using Green's function volume integral equation method

Science.gov (United States)

Soltanmoradi, Elmira; Shokri, Babak

2017-05-01

In this article, the electromagnetic wave scattering from plasma columns with inhomogeneous electron density distribution is studied by the Green's function volume integral equation method. Due to the ready production of such plasmas in the laboratories and their practical application in various technological fields, this study tries to find the effects of plasma parameters such as the electron density, radius, and pressure on the scattering cross-section of a plasma column. Moreover, the incident wave frequency influence of the scattering pattern is demonstrated. Furthermore, the scattering cross-section of a plasma column with an inhomogeneous collision frequency profile is calculated and the effect of this inhomogeneity is discussed first in this article. These results are especially used to determine the appropriate conditions for radar cross-section reduction purposes. It is shown that the radar cross-section of a plasma column reduces more for a larger collision frequency, for a relatively lower plasma frequency, and also for a smaller radius. Furthermore, it is found that the effect of the electron density on the scattering cross-section is more obvious in comparison with the effect of other plasma parameters. Also, the plasma column with homogenous collision frequency can be used as a better shielding in contrast to its inhomogeneous counterpart.

The Effect of Ramadan Fasting and Weight-Lifting Training on Plasma Volume, Glucose and Lipids Profile of Male Weight-Lifters

Directory of Open Access Journals (Sweden)

Seyed Morteza Tayebi

Full Text Available Objective(sThe purpose of the present study was to evaluate the effect of Ramadan fasting and weight-lifting training on plasma volume, glucose, and lipids profile of male weight-lifter.Materials and MethodsForty male weight-lifters were recruited and divided into 4 groups (n=10 each and as the following groups: control (C, fasting (F, training (T and fasting-training (F-T. The T and F-T groups performed weight-lifting technique trainings and hypertrophy body building (3 sessions/week, 90 min/session. All subjects were asked to complete a medical examination as well as a medical questionnaire to ensure that they were not taking any medication, were free of cardiac, respiratory, renal, and metabolic diseases, and were not using steroids. Blood samples were taken at 24 hr before and 24 hr after one month of fasting and weight-lifting exercise. The plasma volume, fasting blood sugar (FBS, lipid profiles, and lipoproteins were analyzed in blood samples. ResultsBody weight and plasma volume showed significant (P< 0.05 decrease and increase in the F group (P< 0.05 respectively. Also, a significant reduction was observed in F-T group body weight (P< 0.01. A significant increase was found in FBS level of F group (P< 0.05. The lipid profiles and lipoproteins didn’t change significantly in C, F, T and the F-T groups.ConclusionThe effect of Ramadan fasting on body weight and plasma volumes may be closely related to the nutritional diet or biochemical response to fasting.

Development of batch electrolytic enrichment cells with 100-fold volume reduction, control electronic units and neutralization/distillation unit, to enable better sensitivity to be achieved in low-level tritium measurements when liquid scintillation counting follows the enrichment process

International Nuclear Information System (INIS)

Taylor, C.B.

1980-06-01

Full details of the batch-cell tritium enrichment system design are provided including electronic control circuits specially developed for these cells. The system incorporates a new type of concentric electrode cell (outer cathode of mild steel, anode of stainless steel, inner cathode of mild steel) with volume reduction capability 1 l to ca 9 ml. Electrolysis of 20 cells is performed in 2 steps. Down to sample volume ca 20 ml, the cells are series connected at constant currents up to 14.5 A, in the 2nd step, each cell is connected to its own individual current supply (2A) and control circuit. Automatic shut-off at the desired final volume is achieved by sensing the drop in current through the inner cathode as the electrolyte level falls below a PTFE insulator. The large electrode surface area and careful dimensioning at the foot of the cell allow operation with low starting electrolyte concentration 1.5 g Na 2 O 2 .l -1 . After electrolysis, quantitative recovery as distilled water of all hydrogen from the enriched residue is achieved by CO 2 -neutralisation and vacuum distillation at 100 0 C in a distillation unit which handles 20 cells simultaneously

NJP VOLUME 41 NO 2

African Journals Online (AJOL)

PROF. EZECHUKWU

2013-11-24

Nov 24, 2013 ... nation and volume of urine voided; from1- 2 times to 10. -15 times during the day ... Serum electrolytes, urea and creatinine done on admis- sion showed ... cient synthesis and or release of AVP.7The clinical manifestation of ...

A new thin film deposition process by cathodic plasma electrolysis

International Nuclear Information System (INIS)

Paulmier, T.; Kiriakos, E.; Bell, J.; Fredericks, P.

2004-01-01

Full text: A new technique, called atmospheric pressure plasma deposition (APPD), has been developed since a few years for the deposition of carbon and DLC, Titanium or Silicon films on metal and metal alloys substrates. A high voltage (2kV) is applied in a liquid electrolytic solution between an anode and a cathode, both electrodes being cylindrical: a glow discharge is then produced and confined at the vicinity of the cathode. The physic of the plasma in the electrolytic solution near the cathode is very different form the other techniques of plasma deposition since the pressure is here close to the atmospheric pressure. We describe here the different physico-chemical processes occurring during the process. In this cathodic process, the anodic area is significantly larger than the cathode area. In a first step, the electrolytic solution is heated by Joule effect induced by the high voltage between the electrodes. Due to the high current density, the vaporization of the solution occurs near the cathode: a large amount of bubbles are produced which are stabilized at the electrode by hydrodynamic and electromagnetic forces, forming a vapour sheath. The electric field and voltage drop are then concentrated in this gas envelope, inducing the ionization of the gas and the ignition of a glow discharge at the surface of the material. This plasma induces the formation of ionized and reactive species which diffuse and are accelerated toward the cathode. These excited species are the precursors for the formation of the deposition material. At the same time, the glow discharge interacts with the electrolyte solution inducing also ionization, convection and polymerization processes in the liquid: the solution is therefore a second source of the deposition material. A wide range of films have been deposited with a thickness up to 10 micrometers. These films have been analyzed by SEM and Raman spectroscopy. The electrolytic solution has been characterized by GC-MS and the

Computational Fluid Dynamics Modeling of a Lithium/Thionyl Chloride Battery with Electrolyte Flow

Energy Technology Data Exchange (ETDEWEB)

Gu, W.B.; Jungst, Rudolph G.; Nagasubramanian, Ganesan; Wang, C.Y.; Weidner, John.

1999-06-11

A two-dimensional model is developed to simulate discharge of a lithium/thionyl chloride primary battery. The model accounts for not only transport of species and charge, but also the electrode porosity variations and the electrolyte flow induced by the volume reduction caused by electrochemical reactions. Numerical simulations are performed using a finite volume method of computational fluid dynamics. The predicted discharge curves for various temperatures are compared to the experimental data with excellent agreement. Moreover, the simulation results. in conjunction with computer visualization and animation techniques, confirm that cell utilization in the temperature and current range of interest is limited by pore plugging or clogging of the front side of the cathode as a result of LiCl precipitation. The detailed two-dimensional flow simulation also shows that the electrolyte is replenished from the cell header predominantly through the separator into the front of the cathode during most parts of the discharge, especially for higher cell temperatures.

Electrolyte materials - Issues and challenges

International Nuclear Information System (INIS)

Balbuena, Perla B.

2014-01-01

Electrolytes are vital components of an electrochemical energy storage device. They are usually composed of a solvent or mixture of solvents and a salt or a mixture of salts which provide the appropriate environment for ionic conduction. One of the main issues associated with the selection of a proper electrolyte is that its electronic properties have to be such that allow a wide electrochemical window - defined as the voltage range in which the electrolyte is not oxidized or reduced - suitable to the battery operating voltage. In addition, electrolytes must have high ionic conductivity and negligible electronic conductivity, be chemically stable with respect to the other battery components, have low flammability, and low cost. Weak stability of the electrolyte against oxidation or reduction leads to the formation of a solid-electrolyte interphase (SEI) layer at the surface of the cathode and anode respectively. Depending on the materials of the electrolyte and those of the electrode, the SEI layer may be composed by combinations of organic and inorganic species, and it may exert a passivating role. In this paper we discuss the current status of knowledge about electrolyte materials, including non-aqueous liquids, ionic liquids, solid ceramic and polymer electrolytes. We also review the basic knowledge about the SEI layer formation, and challenges for a rational design of stable electrolytes

Operating mechanisms of electrolytes in magnesium ion batteries: chemical equilibrium, magnesium deposition, and electrolyte oxidation.

Science.gov (United States)

Kim, Dong Young; Lim, Younhee; Roy, Basab; Ryu, Young-Gyoon; Lee, Seok-Soo

2014-12-21

Since the early nineties there have been a number of reports on the experimental development of Mg electrolytes based on organo/amide-magnesium chlorides and their transmetalations. However, there are no theoretical papers describing the underlying operating mechanisms of Mg electrolytes, and there is no clear understanding of these mechanisms. We have therefore attempted to clarify the operating mechanisms of Mg electrolytes by studying the characteristics of Mg complexes, solvation, chemical equilibrium, Mg-deposition processes, electrolyte-oxidation processes, and oxidative degradation mechanism of RMgCl-based electrolytes, using ab initio calculations. The formation and solvation energies of Mg complexes highly depend on the characteristics of R groups. Thus, changes in R groups of RMgCl lead to changes in the equilibrium position and the electrochemical reduction and oxidation pathways and energies. We first provide a methodological scheme for calculating Mg reduction potential values in non-aqueous electrolytes and electrochemical windows. We also describe a strategy for designing Mg electrolytes to maximize the electrochemical windows and oxidative stabilities. These results will be useful not only for designing improved Mg electrolytes, but also for developing new electrolytes in the future.

Copper Antimonide Nanowire Array Lithium Ion Anodes Stabilized by Electrolyte Additives.

Science.gov (United States)

Jackson, Everett D; Prieto, Amy L

2016-11-09

Nanowires of electrochemically active electrode materials for lithium ion batteries represent a unique system that allows for intensive investigations of surface phenomena. In particular, highly ordered nanowire arrays produced by electrodeposition into anodic aluminum oxide templates can lead to new insights into a material's electrochemical performance by providing a high-surface-area electrode with negligible volume expansion induced pulverization. Here we show that for the Li-Cu x Sb ternary system, stabilizing the surface chemistry is the most critical factor for promoting long electrode life. The resulting solid electrolyte interphase is analyzed using a mix of electron microscopy, X-ray photoelectron spectroscopy, and lithium ion battery half-cell testing to provide a better understanding of the importance of electrolyte composition on this multicomponent alloy anode material.

How Solid-Electrolyte Interphase Forms in Aqueous Electrolytes.

Science.gov (United States)

Suo, Liumin; Oh, Dahyun; Lin, Yuxiao; Zhuo, Zengqing; Borodin, Oleg; Gao, Tao; Wang, Fei; Kushima, Akihiro; Wang, Ziqiang; Kim, Ho-Cheol; Qi, Yue; Yang, Wanli; Pan, Feng; Li, Ju; Xu, Kang; Wang, Chunsheng

2017-12-27

Solid-electrolyte interphase (SEI) is the key component that enables all advanced electrochemical devices, the best representative of which is Li-ion battery (LIB). It kinetically stabilizes electrolytes at potentials far beyond their thermodynamic stability limits, so that cell reactions could proceed reversibly. Its ad hoc chemistry and formation mechanism has been a topic under intensive investigation since the first commercialization of LIB 25 years ago. Traditionally SEI can only be formed in nonaqueous electrolytes. However, recent efforts successfully transplanted this concept into aqueous media, leading to significant expansion in the electrochemical stability window of aqueous electrolytes from 1.23 V to beyond 4.0 V. This not only made it possible to construct a series of high voltage/energy density aqueous LIBs with unprecedented safety, but also brought high flexibility and even "open configurations" that have been hitherto unavailable for any LIB chemistries. While this new class of aqueous electrolytes has been successfully demonstrated to support diversified battery chemistries, the chemistry and formation mechanism of the key component, an aqueous SEI, has remained virtually unknown. In this work, combining various spectroscopic, electrochemical and computational techniques, we rigorously examined this new interphase, and comprehensively characterized its chemical composition, microstructure and stability in battery environment. A dynamic picture obtained reveals how a dense and protective interphase forms on anode surface under competitive decompositions of salt anion, dissolved ambient gases and water molecule. By establishing basic laws governing the successful formation of an aqueous SEI, the in-depth understanding presented in this work will assist the efforts in tailor-designing better interphases that enable more energetic chemistries operating farther away from equilibria in aqueous media.

Potential formation in a collisionless plasma produced in an open magnetic field in presence of volume negative ion source

International Nuclear Information System (INIS)

Phukan, Ananya; Goswami, K. S.; Bhuyan, P. J.

2014-01-01

The electric potential near a wall for a multi-species plasma with volume produced negative ions in presence of axially varying magnetic field is studied following an analytical-numerical approach. A constant negative ion source is assumed throughout the plasma volume, along with finite temperature positive ions and Boltzmann electrons. The particles are assumed to be guided by an open magnetic field that has its maximum at the centre, and field strength decreasing towards the walls. The one dimensional (1D) Poisson equation is derived using an analytical approach, and then solved numerically to study the potential profiles. Effect of (a) negative ion production rate, (b) magnetic field profile, and (c) negative ion temperature on the potential profile has been investigated. A potential peak appears near the wall when the negative ion temperature and density are sufficiently high. Also, the presence of negative ions further decreases the potential in the plasma region for a finite Debye Length (λ D )

What is the fundamental ion-specific series for anions and cations? Ion specificity in standard partial molar volumes of electrolytes and electrostriction in water and non-aqueous solvents† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc02691a Click here for additional data file.

Science.gov (United States)

Mazzini, Virginia

2017-01-01

The importance of electrolyte solutions cannot be overstated. Beyond the ionic strength of electrolyte solutions the specific nature of the ions present is vital in controlling a host of properties. Therefore ion specificity is fundamentally important in physical chemistry, engineering and biology. The observation that the strengths of the effect of ions often follows well established series suggests that a single predictive and quantitative description of specific-ion effects covering a wide range of systems is possible. Such a theory would revolutionise applications of physical chemistry from polymer precipitation to drug design. Current approaches to understanding specific-ion effects involve consideration of the ions themselves, the solvent and relevant interfaces and the interactions between them. Here we investigate the specific-ion effects trends of standard partial molar volumes and electrostrictive volumes of electrolytes in water and eleven non-aqueous solvents. We choose these measures as they relate to bulk properties at infinite dilution, therefore they are the simplest electrolyte systems. This is done to test the hypothesis that the ions alone exhibit a specific-ion effect series that is independent of the solvent and unrelated to surface properties. The specific-ion effects trends of standard partial molar volumes and normalised electrostrictive volumes examined in this work show a fundamental ion-specific series that is reproduced across the solvents, which is the Hofmeister series for anions and the reverse lyotropic series for cations, supporting the hypothesis. This outcome is important in demonstrating that ion specificity is observed at infinite dilution and demonstrates that the complexity observed in the manifestation of specific-ion effects in a very wide range of systems is due to perturbations of solvent, surfaces and concentration on the underlying fundamental series. This knowledge will guide a general understanding of specific

Ionic Liquid-Doped Gel Polymer Electrolyte for Flexible Lithium-Ion Polymer Batteries

Science.gov (United States)

Zhang, Ruisi; Chen, Yuanfen; Montazami, Reza

2015-01-01

Application of gel polymer electrolytes (GPE) in lithium-ion polymer batteries can address many shortcomings associated with liquid electrolyte lithium-ion batteries. Due to their physical structure, GPEs exhibit lower ion conductivity compared to their liquid counterparts. In this work, we have investigated and report improved ion conductivity in GPEs doped with ionic liquid. Samples containing ionic liquid at a variety of volume percentages (vol %) were characterized for their electrochemical and ionic properties. It is concluded that excess ionic liquid can damage internal structure of the batteries and result in unwanted electrochemical reactions; however, samples containing 40–50 vol % ionic liquid exhibit superior ionic properties and lower internal resistance compared to those containing less or more ionic liquids.

Surface and capillary forces encountered by zinc sulfide microspheres in aqueous electrolyte.

Science.gov (United States)

Gillies, Graeme; Kappl, Michael; Butt, Hans-Jürgen

2005-06-21

The colloid probe technique was used to investigate the interactions between individual zinc sulfide (ZnS) microspheres and an air bubble in electrolyte solution. Incorporation of zinc ions into the electrolyte solution overcomes the disproportionate zinc ion dissolution and mimics high-volume-fraction conditions common in flotation. Determined interaction forces revealed a distinct lack of long-ranged hydrophobic forces, indicated by the presence of a DLVO repulsion prior to particle engulfment. Single microsphere contact angles were determined from particle-bubble interactions. Contact angles increased with decreasing radii and with surface oxidation. Surface modification by the absorption of copper and subsequently potassium O-ethyldithiocarbonate (KED) reduced repulsive forces and strongly increased contact angles.

Constructions of aluminium electrolytic cells

International Nuclear Information System (INIS)

Galushkin, N.V.

1995-01-01

This chapter of monograph is devoted to constructions of aluminium electrolytic cells. Therefore, the general characteristic and classification of aluminium electrolytic cells was considered. The anode and cathode structure was studied. The lining of cathode casing, the process of collection of anode gases, electrolytic cell cover, and electrical insulation was studied as well. The installation and dismantling of aluminium electrolytic cells was described.

Large volume serial section tomography by Xe Plasma FIB dual beam microscopy

Energy Technology Data Exchange (ETDEWEB)

Burnett, T.L. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); FEI Company, Achtseweg Noord 5, Bldg, 5651 GG, Eindhoven (Netherlands); Kelley, R. [FEI Company, 5350 NE Dawson Creek Drive, Hillsboro, OR 97124 (United States); Winiarski, B. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); FEI Company, Achtseweg Noord 5, Bldg, 5651 GG, Eindhoven (Netherlands); Contreras, L. [FEI Company, 5350 NE Dawson Creek Drive, Hillsboro, OR 97124 (United States); Daly, M.; Gholinia, A.; Burke, M.G. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Withers, P.J., E-mail: P.J.Withers@manchester.ac.uk [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); BP International Centre for Advanced Materials, University of Manchester, Manchester M13 9PL (United Kingdom)

2016-02-15

Ga{sup +} Focused Ion Beam-Scanning Electron Microscopes (FIB-SEM) have revolutionised the level of microstructural information that can be recovered in 3D by block face serial section tomography (SST), as well as enabling the site-specific removal of smaller regions for subsequent transmission electron microscope (TEM) examination. However, Ga{sup +} FIB material removal rates limit the volumes and depths that can be probed to dimensions in the tens of microns range. Emerging Xe{sup +} Plasma Focused Ion Beam-Scanning Electron Microscope (PFIB-SEM) systems promise faster removal rates. Here we examine the potential of the method for large volume serial section tomography as applied to bainitic steel and WC–Co hard metals. Our studies demonstrate that with careful control of milling parameters precise automated serial sectioning can be achieved with low levels of milling artefacts at removal rates some 60× faster. Volumes that are hundreds of microns in dimension have been collected using fully automated SST routines in feasible timescales (<24 h) showing good grain orientation contrast and capturing microstructural features at the tens of nanometres to the tens of microns scale. Accompanying electron back scattered diffraction (EBSD) maps show high indexing rates suggesting low levels of surface damage. Further, under high current Ga{sup +} FIB milling WC–Co is prone to amorphisation of WC surface layers and phase transformation of the Co phase, neither of which have been observed at PFIB currents as high as 60 nA at 30 kV. Xe{sup +} PFIB dual beam microscopes promise to radically extend our capability for 3D tomography, 3D EDX, 3D EBSD as well as correlative tomography. - Highlights: • The uptake of dual beam FIBs has been rapid but long milling times have limited imaged volumes to tens of micron dimensions. • Emerging plasma Xe{sup +} PFIB-SEM technology offers materials removal rates at least 60× greater than conventional Ga{sup +} FIB systems with

Gas-discharge plasma processes for surface modification and conversion of chemical substances. Application for fuel cells

Energy Technology Data Exchange (ETDEWEB)

Schroeder, K.; Meyer, D.; Rohland, B.; Heintze, M.; Zahn, R.J.; Hannemann, M.; Meusinger, J.; Ohl, A. [Institute of Non-Thermal Plasma Physics, Greifswald (Germany)]|[Gesellschaft fuer Angewandte Technik mbH Greifswald (Germany)]|[GAPC, Adam Opel AG, IPC, Ruesselsheim (Germany)

2001-07-01

The potential of plasma processes towards hydrogen and fuel cell technology will be demonstrated by two examples with preliminary results: 1. plasma modification of polymer electrolyte membranes for direct methanol fuel cells, and 2. plasma supported steam reforming.

Plasma diagnostics package. Volume 1: OSS-1 section

Science.gov (United States)

Pickett, Jolene S. (Compiler); Frank, L. A. (Compiler); Kurth, W. S. (Compiler)

1988-01-01

This volume (1) of the Plasma Diagnostics Package (PDP) final science report contains a summary of all of the data reduction and scientific analyses which were performed using PDP data obtained on STS-3 as a part of the Office of Space Science first payload (OSS-1). This work was performed during the period of launch, March 22, l982, through June 30, l983. During this period the primary data reduction effort consisted of processing summary plots of the data received by the 14 instruments located on the PDP and submitting these data to the National Space Science Data Center (NSSDC). The scientific analyses during the performance period consisted of general studies which incorporated the results of several of the PDP's instruments, detailed studies which concentrated on data from only one or two of the instruments, and joint studies of beam-plasma interactions with the OSS-1 Fast Pulse Electron Generator (FPEG) of the Vehicle Charging and Potential Investigation (VCAP). Internal reports, published papers and oral presentations which involve PDP/OSS-1 data are listed in Sections 3 and 4. A PDP/OSS-1 scientific results meeting was held at the University of Iowa on April 19-20, 1983. This meeting was attended by most of the PDP and VCAP investigators and provided a forum for discussing and comparing the various results, particularly with regard to the shuttle orbiter environment. One of the most important functional objectives of the PDP on OSS-1 was to characterize the orbiter environment.

A molecular dynamics study of lithium-containing aprotic heterocyclic ionic liquid electrolytes

Science.gov (United States)

Lourenço, Tuanan C.; Zhang, Yong; Costa, Luciano T.; Maginn, Edward J.

2018-05-01

Classical molecular dynamics simulations were performed on twelve different ionic liquids containing aprotic heterocyclic anions doped with Li+. These ionic liquids have been shown to be promising electrolytes for lithium ion batteries. Self-diffusivities, lithium transference numbers, densities, and free volumes were computed as a function of lithium concentration. The dynamics and free volume decreased with increasing lithium concentration, and the trends were rationalized by examining the changes to the liquid structure. Of those examined in the present work, it was found that (methyloxymethyl)triethylphosphonium triazolide ionic liquids have the overall best performance.

Modification of the Steel Surface Treated by a Volume Discharge Plasma in Nitrogen at Atmospheric Pressure

Science.gov (United States)

Erofeev, M. V.; Shulepov, M. A.; Ivanov, Yu. F.; Oskomov, K. V.; Tarasenko, V. F.

2016-03-01

Effect of volume discharge plasma initiated by an avalanche electron beam on the composition, structure, and properties of the surface steel layer is investigated. Voltage pulses with incident wave amplitude up to 30 kV, full width at half maximum of about 4 ns, and wave front of about 2.5 ns were applied to the gap with an inhomogeneous electric field. Changes indicating the hardening effect of the volume discharge initiated by an avalanche electron beam are revealed in St3-grade steel specimens treated by the discharge of this type.

Effect of strong electrolytes on edible oils part II: vViscosity of maize ...

African Journals Online (AJOL)

The electrolytes behave as structure breaker. The effect of temperature was also determined in terms of fluidity parameters, energy of activation, latent heat of vaporization, molar volume of oil and free energy change of activation for viscous flow. Journal of Applied Sciences and Environmental Management Vol. 10 (3) 2006: ...

Steroid hormone release as well as renal water and electrolyte excretion of mice expressing PKB/SGK-resistant GSK3.

Science.gov (United States)

Boini, Krishna M; Bhandaru, Madhuri; Mack, Andreas; Lang, Florian

2008-09-01

Insulin and insulin-like growth factor (IGF1) participate in the regulation of renal electrolyte excretion. Insulin- and IGF1-dependent signaling includes phosphatidylinositide-3 (PI3)-kinase, phosphoinositide-dependent kinase PDK1 as well as protein kinase B (PKB) and serum and glucocorticoid inducible kinase (SGK) isoforms, which in turn phosphorylate and thus inhibit glycogen synthase kinase GSK3alpha,beta. Replacement of the serines in the PKB/SGK consensus sequences by alanine (gsk3 ( KI )) confers resistance of GSK3 to PKB/SGK. To explore the role of PKB/SGK-dependent inhibition of GSK3 in the regulation of water/electrolyte metabolism, mice carrying the PKB/SGK resistant mutant (gsk3 ( KI )) were compared to their wild-type littermates (gsk3 ( WT ) ). Body weight was similar in gsk3 ( KI ) and gsk3 ( WT ) mice. Plasma aldosterone at 10 A.M: . and corticosterone concentrations at 5 P.M: . were significantly lower, but 24-h urinary aldosterone was significantly higher, and corticosterone excretion tended to be higher in gsk3 ( KI ) than in gsk3 ( WT ) mice. Food and water intake, fecal excretion, glomerular filtration rate, urinary flow rate, urine osmolarity, as well as urinary Na+, K+, urea excretion were significantly larger, and plasma Na+, urea, but not K+ concentration, were significantly lower in gsk3 ( KI ) than in gsk3 ( WT ) mice. Body temperature was significantly higher in gsk3 ( KI ) than in gsk3 ( WT ) mice. When allowed to choose between tap water and saline, gsk3 ( WT ) mice drank more saline, whereas gsk3 ( KI ) mice drank similar large volumes of tap water and saline. During high-salt diet, urinary vasopressin excretion increased to significantly higher levels in gsk3 ( KI ) than in gsk3 ( WT ) mice. After water deprivation, body weight decreased faster in gsk3 ( KI ) than in gsk3 ( WT ) mice. Blood pressure, however, was significantly higher in gsk3 ( KI ) than in gsk3 ( WT ) mice. The observations disclose a role of PKB/SGK-dependent GSK3

Efficient Electrolytes for Lithium–Sulfur Batteries

International Nuclear Information System (INIS)

Angulakshmi, Natarajan; Stephan, Arul Manuel

2015-01-01

This review article mainly encompasses on the state-of-the-art electrolytes for lithium–sulfur batteries. Different strategies have been employed to address the issues of lithium–sulfur batteries across the world. One among them is identification of electrolytes and optimization of their properties for the applications in lithium–sulfur batteries. The electrolytes for lithium–sulfur batteries are broadly classified as (i) non-aqueous liquid electrolytes, (ii) ionic liquids, (iii) solid polymer, and (iv) glass-ceramic electrolytes. This article presents the properties, advantages, and limitations of each type of electrolytes. Also, the importance of electrolyte additives on the electrochemical performance of Li–S cells is discussed.

Efficient Electrolytes for Lithium-Sulfur Batteries

Directory of Open Access Journals (Sweden)

Natarajan eAngulakshmi

2015-05-01

Full Text Available This review article mainly encompasses on the state-of-the-art electrolytes for lithium–sulfur batteries. Different strategies have been employed to address the issues of lithium-sulfur batteries across the world. One among them is identification of electrolytes and optimization of their properties for the applications in lithium-sulfur batteries. The electrolytes for lithium-sulfur batteries are broadly classified as (i non-aqueous liquid electrolytes, (ii ionic liquids, (iii solid polymer and (iv glass-ceramic electrolytes. This article presents the properties, advantages and limitations of each type of electrolytes. Also the importance of electrolyte additives on the electrochemical performance of Li-S cells is discussed.

Efficient Electrolytes for Lithium–Sulfur Batteries

Energy Technology Data Exchange (ETDEWEB)

Angulakshmi, Natarajan [Department of Materials Science and Engineering, Politecnico di Torino, Turin (Italy); Stephan, Arul Manuel, E-mail: arulmanuel@gmail.com [Central Electrochemical Research Institute (CSIR-CECRI), Karaikudi (India)

2015-05-21

This review article mainly encompasses on the state-of-the-art electrolytes for lithium–sulfur batteries. Different strategies have been employed to address the issues of lithium–sulfur batteries across the world. One among them is identification of electrolytes and optimization of their properties for the applications in lithium–sulfur batteries. The electrolytes for lithium–sulfur batteries are broadly classified as (i) non-aqueous liquid electrolytes, (ii) ionic liquids, (iii) solid polymer, and (iv) glass-ceramic electrolytes. This article presents the properties, advantages, and limitations of each type of electrolytes. Also, the importance of electrolyte additives on the electrochemical performance of Li–S cells is discussed.

Novel Nonflammable Electrolytes for Secondary Magnesium Batteries and High Voltage Electrolytes for Electrochemcial Supercapacitors

Energy Technology Data Exchange (ETDEWEB)

Dixon, Brian

2008-12-30

Magnesium has been used successfully in primary batteries, but its use in rechargeable cells has been stymied by the lack of suitable non-aqueous electrolyte that can conduct Mg+2 species, combined with poor stripping and plating properties. The development of a suitable cathode material for rechargeable magnesium batteries has also been a roadblock, but a nonflammable electrolyte is key. Likewise, the development of safe high voltage electrochemical supercapaitors has been stymied by the use of flammable solvents in the liquid electrolyte; to wit, acetonitrile. The purpose of the research conducted in this effort was to identify useful compositions of magnesium salts and polyphosphate solvents that would enable magnesium ions to be cycled within a secondary battery design. The polyphosphate solvents would provide the solvent for the magnesium salts while preventing the electrolyte from being flammable. This would enable these novel electrolytes to be considered as an alternative to THF-based electrolytes. In addition, we explored several of these solvents together with lithium slats for use as high voltage electrolytes for carbon-based electrochemical supercapacitors. The research was successful in that: 1) Magnesium imide dissolved in a phosphate ester solvent that contains a halogented phosphate ester appears to be the preferred electrolyte for a rechargeable Mg cell. 2) A combination of B-doped CNTs and vanadium phosphate appear to be the cathode of choice for a rechargeable Mg cell by virtue of higher voltage and better reversibility. 3) Magnesium alloys appear to perform better than pure magnesium when used in combination with the novel polyphosphate electrolytes. Also, this effort has established that Phoenix Innovation's family of phosphonate/phosphate electrolytes together with specific lithium slats can be used in supercapacitor systems at voltages of greater than 10V.

Large-current-controllable carbon nanotube field-effect transistor in electrolyte solution

Science.gov (United States)

Myodo, Miho; Inaba, Masafumi; Ohara, Kazuyoshi; Kato, Ryogo; Kobayashi, Mikinori; Hirano, Yu; Suzuki, Kazuma; Kawarada, Hiroshi

2015-05-01

Large-current-controllable carbon nanotube field-effect transistors (CNT-FETs) were fabricated with mm-long CNT sheets. The sheets, synthesized by remote-plasma-enhanced CVD, contained both single- and double-walled CNTs. Titanium was deposited on the sheet as source and drain electrodes, and an electrolyte solution was used as a gate electrode (solution gate) to apply a gate voltage to the CNTs through electric double layers formed around the CNTs. The drain current came to be well modulated as electrolyte solution penetrated into the sheets, and one of the solution gate CNT-FETs was able to control a large current of over 2.5 A. In addition, we determined the transconductance parameter per tube and compared it with values for other CNT-FETs. The potential of CNT sheets for applications requiring the control of large current is exhibited in this study.

Surface Modification of NiTi Alloy via Cathodic Plasma Electrolytic Deposition and its Effect on Ni Ion Release and Osteoblast Behaviors

International Nuclear Information System (INIS)

Yan Ying; Cai Kaiyong; Yang Weihu; Liu Peng

2013-01-01

To reduce Ni ion release and improve biocompatibility of NiTi alloy, the cathodic plasma electrolytic deposition (CPED) technique was used to fabricate ceramic coating onto a NiTi alloy surface. The formation of a coating with a rough and micro-textured surface was confirmed by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, respectively. An inductively coupled plasma mass spectrometry test showed that the formed coating significantly reduced the release of Ni ions from the NiTi alloy in simulated body fluid. The influence of CPED treated NiTi substrates on the biological behaviors of osteoblasts, including cell adhesion, cell viability, and osteogenic differentiation function (alkaline phosphatase), was investigated in vitro. Immunofluorescence staining of nuclei revealed that the CPED treated NiTi alloy was favorable for cell growth. Osteoblasts on CPED modified NiTi alloy showed greater cell viability than those for the native NiTi substrate after 4 and 7 days cultures. More importantly, osteoblasts cultured onto a modified NiTi sample displayed significantly higher differentiation levels of alkaline phosphatase. The results suggested that surface functionalization of NiTi alloy with ceramic coating via the CPED technique was beneficial for cell proliferation and differentiation. The approach presented here is useful for NiTi implants to enhance bone osteointegration and reduce Ni ion release in vitro

Surface Modification of NiTi Alloy via Cathodic Plasma Electrolytic Deposition and its Effect on Ni Ion Release and Osteoblast Behaviors

Science.gov (United States)

Yan, Ying; Cai, Kaiyong; Yang, Weihu; Liu, Peng

2013-07-01

To reduce Ni ion release and improve biocompatibility of NiTi alloy, the cathodic plasma electrolytic deposition (CPED) technique was used to fabricate ceramic coating onto a NiTi alloy surface. The formation of a coating with a rough and micro-textured surface was confirmed by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, respectively. An inductively coupled plasma mass spectrometry test showed that the formed coating significantly reduced the release of Ni ions from the NiTi alloy in simulated body fluid. The influence of CPED treated NiTi substrates on the biological behaviors of osteoblasts, including cell adhesion, cell viability, and osteogenic differentiation function (alkaline phosphatase), was investigated in vitro. Immunofluorescence staining of nuclei revealed that the CPED treated NiTi alloy was favorable for cell growth. Osteoblasts on CPED modified NiTi alloy showed greater cell viability than those for the native NiTi substrate after 4 and 7 days cultures. More importantly, osteoblasts cultured onto a modified NiTi sample displayed significantly higher differentiation levels of alkaline phosphatase. The results suggested that surface functionalization of NiTi alloy with ceramic coating via the CPED technique was beneficial for cell proliferation and differentiation. The approach presented here is useful for NiTi implants to enhance bone osseointegration and reduce Ni ion release in vitro.

Electrolyte for a lithium/thionyl chloride electric cell, a method of preparing said electrolyte and an electric cell which includes said electrolyte

Energy Technology Data Exchange (ETDEWEB)

Gabano, J.

1983-03-01

An electrolyte for an electric cell whose negative active material is constituted by lithium and whose positive active material is constituted by thionyl chloride. The electrolyte contains at least one solvent and at least one solute, said solvent being thionyl chloride and said solute being chosen from the group which includes lithium tetrachloroaluminate and lithium hexachloroantimonate. According to the invention said electrolyte further includes a complex chosen from the group which includes AlCl/sub 3/,SO/sub 2/ and SbCl/sub 5/,SO/sub 2/. The voltage rise of electric cells which include such an electrolyte takes negligible time.

High-performance electrolyte in the presence of dextrose and its derivatives for aluminum electrolytic capacitors

Science.gov (United States)

Tsai, Ming-Liao; Lu, Yi-Fang; Do, Jing-Shan

Dextrose and its derivatives (e.g. glucose, gluconic acid and gluconic lactone) are added to modify the characteristics of electrolytes used in aluminum electrolytic capacitors. The results show that the conductivity and sparking voltage of the electrolytes are severely affected by the concentration of dextrose gluconic acid and gluconic lactone. In addition, the pH of the electrolyte is only slightly affected by the quantity of gluconic acid and gluconic lactone. The capacitance, dissipation factor, and leakage current of capacitors impregnated with the electrolytes prepared in this work are periodically measured under storage conditions and loading at 105 °C.

Effects of cathode pulse at high frequency on structure and composition of Al2TiO5 ceramic coatings on Ti alloy by plasma electrolytic oxidation

International Nuclear Information System (INIS)

Yao Zhongping; Liu Yunfu; Xu Yongjun; Jiang Zhaohua; Wang Fuping

2011-01-01

Research highlights: → Al 2 TiO 5 in the coating on Ti alloy by PEO treatment changes with the increase of the cathode pulse, regardless of the amount and the grain size. → The cathode pulse brings about the decrease of γ-Al 2 O 3 and the increase of rutile TiO 2 in the coating. → The appropriate cathode pulse during PEO process is beneficial to reduce residual discharging channels and improve the density of the coating. - Abstract: The aim of this work is to investigate the effects of cathode pulse under high working frequency on structure and composition of ceramic coatings on Ti-6Al-4V alloys by plasma electrolytic oxidation (PEO). Ceramic coatings were prepared on Ti alloy by pulsed bi-polar plasma electrolytic oxidation in NaAlO 2 solution. The phase composition, morphology and element distribution in the coating were investigated by X-ray diffractometry, scanning electron microscopy and energy distribution spectroscopy, respectively. The coating was mainly composed of a large amount of Al 2 TiO 5 . As the cathode pulse was increased, the amount and grain size of Al 2 TiO 5 were first increased, and then decreased. γ-Al 2 O 3 in the coating was gradually decreased to nothing with the increase in the cathode pulse whereas rutile TiO 2 began to form in the coating. As opposed to the single-polar anode pulse mode, the cathode pulse reduced the thickness of the coatings. However, as the cathode pulse intensity continued to increase, the coating then became thicker regardless of cathode current density or pulse width. In addition, the residual discharging channels were reduced and the density of the coating was increased with the appropriate increase of the cathode pulse.

Ceramic solid electrolytes

Energy Technology Data Exchange (ETDEWEB)

Goodenough, John B. [Center for Materials Science and Engineering, University of Texas at Austin, Austin, TX (United States)

1997-02-15

Strategies for the design of ceramic solid electrolytes are reviewed. Problems associated with stoichiometric and doped compounds are compared. In the illustration of design principles, emphasis is given to oxide-ion electrolytes for use in solid-oxide fuel cells, oxygen pumps, and oxygen sensors

Evaluation of Plasma Electrolytes in Patients Suffering From ...

African Journals Online (AJOL)

Anthropometric indices of all subjects were also determined. The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria and Hamilton Depression Rating Scale were used for diagnosis and measurement of severity of depression respectively. The mean plasma sodium (p<0.05) and potassium (p<0.01) were ...

Gel polymer electrolytes for batteries

Science.gov (United States)

Balsara, Nitash Pervez; Eitouni, Hany Basam; Gur, Ilan; Singh, Mohit; Hudson, William

2014-11-18

Nanostructured gel polymer electrolytes that have both high ionic conductivity and high mechanical strength are disclosed. The electrolytes have at least two domains--one domain contains an ionically-conductive gel polymer and the other domain contains a rigid polymer that provides structure for the electrolyte. The domains are formed by block copolymers. The first block provides a polymer matrix that may or may not be conductive on by itself, but that can soak up a liquid electrolyte, thereby making a gel. An exemplary nanostructured gel polymer electrolyte has an ionic conductivity of at least 1.times.10.sup.-4 S cm.sup.-1 at 25.degree. C.

Lithium carbon batteries with solid polymer electrolyte; Accumulateur lithium carbone a electrolyte solide polymere

Energy Technology Data Exchange (ETDEWEB)

Andrieu, X.; Boudin, F. [Alcatel Alsthom Recherche, 91 - Marcoussis (France)

1996-12-31

The lithium carbon batteries studied in this paper use plasticized polymer electrolytes made with passive polymer matrix swollen by a liquid electrolyte with a high ionic conductivity (> 10{sup -3} S/cm at 25 deg. C). The polymers used to prepare the gels are polyacrylonitrile (PAN) and vinylidene poly-fluoride (PVdF). The electrochemical and physical properties of these materials are analyzed according to their composition. The behaviour of solid electrolytes with different materials of lithium ion insertion (graphite and LiNiO{sub 2}) are studied and compared to liquid electrolytes. The parameters taken into account are the reversible and irreversible capacities, the cycling performance and the admissible current densities. Finally, complete lithium ion batteries with gelled electrolytes were manufactured and tested. (J.S.) 2 refs.

Lithium carbon batteries with solid polymer electrolyte; Accumulateur lithium carbone a electrolyte solide polymere

Energy Technology Data Exchange (ETDEWEB)

Andrieu, X; Boudin, F [Alcatel Alsthom Recherche, 91 - Marcoussis (France)

1997-12-31

The lithium carbon batteries studied in this paper use plasticized polymer electrolytes made with passive polymer matrix swollen by a liquid electrolyte with a high ionic conductivity (> 10{sup -3} S/cm at 25 deg. C). The polymers used to prepare the gels are polyacrylonitrile (PAN) and vinylidene poly-fluoride (PVdF). The electrochemical and physical properties of these materials are analyzed according to their composition. The behaviour of solid electrolytes with different materials of lithium ion insertion (graphite and LiNiO{sub 2}) are studied and compared to liquid electrolytes. The parameters taken into account are the reversible and irreversible capacities, the cycling performance and the admissible current densities. Finally, complete lithium ion batteries with gelled electrolytes were manufactured and tested. (J.S.) 2 refs.

The Effect of Percutaneous Nephrolithotomy Process on Hemodynamic, Electrolyte and Acid-Base Changes

Directory of Open Access Journals (Sweden)

Ercan Baş

2015-10-01

Full Text Available Aim: Operation of percutaneous nephrolithotomy (PNL, is the most commonly used method of renal stone surgery. During this operation, kidney must be continually irrigated with isotonic liquid. In our study, we investigated the volume of irrigation, irrigation duration, input the number of percutaneous renal parenchymal thickness and the degree of this finding the effects of on hemodynamic, electrolyte and metabolic changes. Method: 64 patient with an indication for percutaneous nephrolithotomy were included in the study. Before irrigation, during irrigation and the post- irrigation; pulse, systolic and diastolic blood pressure (bp, electrolytes, arterial blood gases were measured. In preoperative and postoperative 1. and 24. hours hemoglobin, creatinine levels were measured. Before the operation; pelvicaliectasis degree, parenchymal thickness, volume and duration of irrigation and the number of percutaneous entry were recorded in all patients. Results: Following the start of irrigation, changes in diastolic and systolic bp and pulse also not statistically significant. No significant change of partial oxygen, carbon dioxide, and oxygen saturation pressure was observed. After the operation, serum sodium, potassium, calcium values are within normal limits, but when compared with preoperative values the decrease of these values statistically significant were observed. Bicarbonate and ph values with irrigation period had a negative correlation. Although not clinically significant parenchymal thickness was found to be negative correlation with decrease of calcium. Additionally degrees of pelvicaliectasis has been found negative correlation with the decrease of sodium and bicarbonate. Conclusion: Hemodynamics and electrolytes did not change significantly both during and after the PNL process, but metabolic acidosis was observed towards the end of the PNL process. In long-term irrigation, repeated percutaneous entrances, people with moderate and severe

Maternal nutritional status in early pregnancy is associated with body water and plasma volume changes in a pregnancy cohort in rural Bangladesh.

Science.gov (United States)

Gernand, Alison D; Christian, Parul; Schulze, Kerry J; Shaikh, Saijuddin; Labrique, Alain B; Shamim, Abu Ahmed; West, Keith P

2012-06-01

Plasma volume expansion has been associated with fetal growth. Our objective was to examine the associations between maternal nutritional status in early pregnancy and extracellular water (ECW), total body water (TBW), and percentage plasma volume change across pregnancy. In a subsample of 377 pregnant women participating in a cluster-randomized trial of micronutrient supplementation, hemoglobin, hematocrit, and multi-frequency bioelectrical impedance were measured at ~10, 20, and 32 wk of gestation. In early pregnancy, women were short (mean ± SD, 148.9 ± 5.3 cm) and thin (19.5 ± 2.5 kg/m(2)). In mixed-effects multiple regression models, a 1-unit higher BMI at ~10 wk was associated with higher ECW and TBW (0.27 and 0.66 kg per kg/m(2), respectively; P pregnancy BMI was negatively associated with gains in ECW and TBW (-0.06 and -0.14 kg per kg/m(2), respectively; P pregnancy have lower ECW and TBW in early, mid, and late pregnancy and lower late pregnancy plasma volume expansion, potentially increasing risk of fetal growth restriction.

Ionic Liquid-Doped Gel Polymer Electrolyte for Flexible Lithium-Ion Polymer Batteries

Directory of Open Access Journals (Sweden)

Ruisi Zhang

2015-05-01

Full Text Available Application of gel polymer electrolytes (GPE in lithium-ion polymer batteries can address many shortcomings associated with liquid electrolyte lithium-ion batteries. Due to their physical structure, GPEs exhibit lower ion conductivity compared to their liquid counterparts. In this work, we have investigated and report improved ion conductivity in GPEs doped with ionic liquid. Samples containing ionic liquid at a variety of volume percentages (vol % were characterized for their electrochemical and ionic properties. It is concluded that excess ionic liquid can damage internal structure of the batteries and result in unwanted electrochemical reactions; however, samples containing 40–50 vol % ionic liquid exhibit superior ionic properties and lower internal resistance compared to those containing less or more ionic liquids.

Quiescent plasma machine for plasma investigation

International Nuclear Information System (INIS)

Ferreira, J.L.

1993-01-01

A large volume quiescent plasma device is being developed at INPE to study Langmuir waves and turbulence generated by electron beams (E b ≤ 500 e V) interacting with plasma. This new quiescent plasma machine was designed to allow the performance of several experiments specially those related with laboratory space plasma simulation experiments. Current-driven instabilities and related phenomena such as double-layers along magnetic field lines are some of the many experiments planned for this machine. (author)

Plasma diagnostics package. Volume 2: Spacelab 2 section, part A

Science.gov (United States)

Pickett, Jolene S. (Compiler); Frank, L. A. (Compiler); Kurth, W. S. (Compiler)

1988-01-01

This volume (2), which consists of two parts (A and B), of the Plasma Diagnostics Package (PDP) Final Science Report contains a summary of all of the data reduction and scientific analyses which were performed using PDP data obtained on STS-51F as a part of the Spacelab 2 (SL-2) payload. This work was performed during the period of launch, July 29, l985, through June 30, l988. During this period the primary data reduction effort consisted of processing summary plots of the data received by 12 of the 14 instruments located on the PDP and submitting these data to the National Space Science Data Center (NSSDC). The scientific analyses during the performance period consisted of follow-up studies of shuttle orbiter environment and orbiter/ionosphere interactions and various plasma particle and wave studies which dealt with data taken when the PDP was on the Remote Manipulator System (RMS) arm and when the PDP was in free flight. Of particular interest during the RMS operations and free flight were the orbiter wake studies and joint studies of beam/plasma interactions with the SL-2 Fast Pulse Electron Generator (FPEG) of the Vehicle Charging and Potential Investigation (VCAP). Internal reports, published papers and presentations which involve PDP/SL-2 data are listed in Sections 3 and 4. A PDP/SL-2 scientific results meeting was held at the University of Iowa on June 10, l986. This meeting was attended by most of the PDP and VCAP investigators and provided a forum for discussing and comparing the various results, particularly with regard to the PDP free flight.

Enhancing Capacity Performance by Utilizing the Redox Chemistry of the Electrolyte in a Dual-Electrolyte Sodium-Ion Battery.

Science.gov (United States)

Senthilkumar, Sirugaloor Thangavel; Bae, Hyuntae; Han, Jinhyup; Kim, Youngsik

2018-05-04

A strategy is described to increase charge storage in a dual electrolyte Na-ion battery (DESIB) by combining the redox chemistry of the electrolyte with a Na + ion de-insertion/insertion cathode. Conventional electrolytes do not contribute to charge storage in battery systems, but redox-active electrolytes augment this property via charge transfer reactions at the electrode-electrolyte interface. The capacity of the cathode combined with that provided by the electrolyte redox reaction thus increases overall charge storage. An aqueous sodium hexacyanoferrate (Na 4 Fe(CN) 6 ) solution is employed as the redox-active electrolyte (Na-FC) and sodium nickel Prussian blue (Na x -NiBP) as the Na + ion insertion/de-insertion cathode. The capacity of DESIB with Na-FC electrolyte is twice that of a battery using a conventional (Na 2 SO 4 ) electrolyte. The use of redox-active electrolytes in batteries of any kind is an efficient and scalable approach to develop advanced high-energy-density storage systems. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

OH – on plasma electrolytic oxidation of Ti–5Mo–4V–3Al

Indian Academy of Sciences (India)

Corrosion resistance is evaluated by open circuit potential (OCP) variation of samples in NaCl 3.5% and potentiodynamic polarization. The results show that the unstable film is formed by using more aggressive PEO electrolyte. By increasing this ratio, pore size varied from fine to coarse and the rate of corrosion decreased ...

Increased volume of distribution for recombinant activated factor VII and longer plasma-derived factor VII half-life may explain their long lasting prophylactic effect.

Science.gov (United States)

Mathijssen, Natascha C J; Masereeuw, Rosalinde; Holme, Pal Andre; van Kraaij, Marian G J; Laros-van Gorkom, Britta A P; Peyvandi, Flora; van Heerde, Waander L

2013-08-01

Prophylaxis with plasma-derived or recombinant activated factor VII is beneficial in severe factor VII deficiency. To understand why prophylactic treatment with both products is efficacious, we conducted a pharmacokinetic study. Ten factor VII deficient patients were treated with either recombinant activated (20 μg/kg) or plasma-derived (25 IU/kg) factor VII in a cross-over design. Pharmacokinetic parameters were analyzed through activated factor VII activity, factor VII clotting activity, and factor VII antigen levels on depicted time points. Factor VII activity half-lifes, determined by non-compartmental and one-compartmental analysis (results in brackets), were shorter for recombinant activated (1.4h; 0.7h) than for plasma-derived factor VII (6.8h; 3.2h); both recombinant activated (5.1h; 2.1h and plasma-derived factor VII (5.8h; 3.2h) resulted in longer half-lives of factor VII antigen. Activated factor VII half-lives (based on activated factor VII activity levels) were significantly higher compared to factor VII clotting activity (1.6h; 0.9h). Volumes of distribution were significantly higher for activated factor VII (236 ml/kg; 175 ml/kg, measured by activated factor VII) as compared to plasma-derived factor VII (206 ml/kg; 64 ml/kg, measured by factor FVII activity), suggesting a plasma- and extracellular fluid distribution for recombinant activated factor VII. Recombinant activated factor VII showed significantly shorter half-lifes than plasma-derived factor VII. Volumes of distribution were significantly higher for treatment with recombinant activated factor VII. The longer half-life for plasma-derived factor VII, compared to recombinant activated factor VII, and the increased volume of distribution for recombinant activated factor VII, compared to plasma-derived factor VII may further elucidate the beneficial effect of prophylactic treatment of both products. Copyright © 2013 Elsevier Ltd. All rights reserved.

Open loop control of filament heating power supply for large volume plasma device

Energy Technology Data Exchange (ETDEWEB)

Sugandhi, R., E-mail: ritesh@ipr.res.in [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Mumbai 400094 (India); Srivastava, P.K.; Sanyasi, A.K. [Homi Bhabha National Institute, Mumbai 400094 (India); Srivastav, Prabhakar [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Mumbai 400094 (India); Awasthi, L.M., E-mail: kushagra.lalit@gmail.com [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Mumbai 400094 (India); Mattoo, S.K. [Homi Bhabha National Institute, Mumbai 400094 (India)

2017-02-15

A power supply (20 V, 10 kA) for powering the filamentary cathode has been procured, interfaced and integrated with the centralized control system of Large Volume Plasma Device (LVPD). Software interface has been developed on the standard Modbus RTU communication protocol. It facilitates the dashboard for configuration, on line status monitoring, alarm management, data acquisition, synchronization and controls. It has been tested for stable operation of the power supply for the operational capabilities. The paper highlights the motivation, interface description, implementation and results obtained.

Open loop control of filament heating power supply for large volume plasma device

International Nuclear Information System (INIS)

Sugandhi, R.; Srivastava, P.K.; Sanyasi, A.K.; Srivastav, Prabhakar; Awasthi, L.M.; Mattoo, S.K.

2017-01-01

A power supply (20 V, 10 kA) for powering the filamentary cathode has been procured, interfaced and integrated with the centralized control system of Large Volume Plasma Device (LVPD). Software interface has been developed on the standard Modbus RTU communication protocol. It facilitates the dashboard for configuration, on line status monitoring, alarm management, data acquisition, synchronization and controls. It has been tested for stable operation of the power supply for the operational capabilities. The paper highlights the motivation, interface description, implementation and results obtained.

Double-membrane triple-electrolyte redox flow battery design

Science.gov (United States)

Yushan, Yan; Gu, Shuang; Gong, Ke

2018-03-13

A redox flow battery is provided having a double-membrane (one cation exchange membrane and one anion exchange membrane), triple-electrolyte (one electrolyte in contact with the negative electrode, one electrolyte in contact with the positive electrode, and one electrolyte positioned between and in contact with the two membranes). The cation exchange membrane is used to separate the negative or positive electrolyte and the middle electrolyte, and the anion exchange membrane is used to separate the middle electrolyte and the positive or negative electrolyte. This design physically isolates, but ionically connects, the negative electrolyte and positive electrolyte. The physical isolation offers great freedom in choosing redox pairs in the negative electrolyte and positive electrolyte, making high voltage of redox flow batteries possible. The ionic conduction drastically reduces the overall ionic crossover between negative electrolyte and positive one, leading to high columbic efficiency.

Bioactivity and biocompatibility of hydroxyapatite-based bioceramic coatings on zirconium by plasma electrolytic oxidation.

Science.gov (United States)

Aktuğ, Salim Levent; Durdu, Salih; Yalçın, Emine; Çavuşoğlu, Kültigin; Usta, Metin

2017-02-01

In the present work, hydroxyapatite (HAP)-based plasma electrolytic oxide (PEO) coatings were produced on zirconium at different current densities in a solution containing calcium acetate and β-calcium glycerophosphate by a single step. The phase structure, surface morphology, functional groups, thickness and roughness of the coatings were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), eddy current method and surface profilometer, respectively. The phases of cubic-zirconia, calcium zirconate and HAP were detected by XRD. The amount of HAP and calcium zirconate increased with increasing current density. The surface of the coatings was very porous and rough. Moreover, bioactivity and biocompatibility of the coatings were analyzed in vitro immersion simulated body fluid (SBF) and MTT (3-(4,5-dimethyl thiazol-2yl)-2,5-diphenyl tetrazolium bromide) assay, hemolysis assay and bacterial formation. The apatite-forming ability of the coatings was evaluated after immersion in SBF up to 28days. After immersion, the bioactivity of HAP-based coatings on zirconium was greater than the ones of uncoated zirconium and zirconium oxide-based surface. The bioactivity of PEO surface on zirconium was significantly improved under SBF conditions. The bacterial adhesion of the coatings decreased with increasing current density. The bacterial adhesion of the coating produced at 0.370A/cm 2 was minimum compared to uncoated zirconium coated at 0.260 and 0.292A/cm 2 . The hemocompatibility of HAP-based surfaces was improved by PEO. The cell attachment and proliferation of the PEO coatings were better than the one of uncoated zirconium according to MTT assay results. Copyright © 2016 Elsevier B.V. All rights reserved.

POLYMER ELECTROLYTE MEMBRANE FUEL CELLS

DEFF Research Database (Denmark)

2001-01-01

A method for preparing polybenzimidazole or polybenzimidazole blend membranes and fabricating gas diffusion electrodes and membrane-electrode assemblies is provided for a high temperature polymer electrolyte membrane fuel cell. Blend polymer electrolyte membranes based on PBI and various...... thermoplastic polymers for high temperature polymer electrolyte fuel cells have also been developed. Miscible blends are used for solution casting of polymer membranes (solid electrolytes). High conductivity and enhanced mechanical strength were obtained for the blend polymer solid electrolytes....... With the thermally resistant polymer, e.g., polybenzimidazole or a mixture of polybenzimidazole and other thermoplastics as binder, the carbon-supported noble metal catalyst is tape-cast onto a hydrophobic supporting substrate. When doped with an acid mixture, electrodes are assembled with an acid doped solid...

Practical high temperature (80 °C) storage study of industrially manufactured Li-ion batteries with varying electrolytes

Science.gov (United States)

Genieser, R.; Loveridge, M.; Bhagat, R.

2018-05-01

A previous study is focused on high temperature cycling of industrially manufactured Li-ion pouch cells (NMC-111/Graphite) with different electrolytes at 80 °C [JPS 373 (2018) 172-183]. Within this article the same test set-up is used, with cells stored for 30 days at different open circuit potentials and various electrolytes instead of electrochemical cycling. The most pronounced cell degradation (capacity fade and resistance increase) happens at high potentials. However appropriate electrolyte formulations are able to suppress ageing conditions by forming passivating surface films on both electrodes. Compared with electrochemical cycling at 80 °C, cells with enhanced electrolytes only show a slight resistance increase during storage and the capacity fade is much lower. Additionally it is shown for the first time, that the resistance is decreasing and capacity is regained once these cells are cycled again at room temperature. This is not the case for electrolytes without additives or just vinylene carbonate (VC) as an additive. It is further shown that the resistance increase of cells with the other electrolytes is accompanied by a reduction of the cell volume during further cycling. This behaviour is likely related to the reduction of CO2 at the anode to form additional SEI layer components.

NJP VOLUME 39 No 4

African Journals Online (AJOL)

Prof Ezechukwu

2012-02-28

Feb 28, 2012 ... Disorders affecting fluid volume and electrolyte compo- sition are common ... knowledge of the mechanism of action of diuretic drugs and appropriate ... Presence of non-permeable solute will oppose H2O ex- traction. NaCl is actively .... loop not affected. • In oral administration rate and extent of absorption.

Plasma processing for VLSI

CERN Document Server

Einspruch, Norman G

1984-01-01

VLSI Electronics: Microstructure Science, Volume 8: Plasma Processing for VLSI (Very Large Scale Integration) discusses the utilization of plasmas for general semiconductor processing. It also includes expositions on advanced deposition of materials for metallization, lithographic methods that use plasmas as exposure sources and for multiple resist patterning, and device structures made possible by anisotropic etching.This volume is divided into four sections. It begins with the history of plasma processing, a discussion of some of the early developments and trends for VLSI. The second section

Multiple-membrane multiple-electrolyte redox flow battery design

Science.gov (United States)

Yan, Yushan; Gu, Shuang; Gong, Ke

2017-05-02

A redox flow battery is provided. The redox flow battery involves multiple-membrane (at least one cation exchange membrane and at least one anion exchange membrane), multiple-electrolyte (one electrolyte in contact with the negative electrode, one electrolyte in contact with the positive electrode, and at least one electrolyte disposed between the two membranes) as the basic characteristic, such as a double-membrane, triple electrolyte (DMTE) configuration or a triple-membrane, quadruple electrolyte (TMQE) configuration. The cation exchange membrane is used to separate the negative or positive electrolyte and the middle electrolyte, and the anion exchange membrane is used to separate the middle electrolyte and the positive or negative electrolyte.

Blood Volume, Plasma Volume and Circulation Time in a High-Energy-Demand Teleost, the Yellowfin Tuna (Thunnus Albacares)

DEFF Research Database (Denmark)

Brill, R.W.; Cousins, K.L.; Jones, D.R.

1998-01-01

We measured red cell space with 51Cr-labeled red blood cells, and dextran space with 500 kDa fluorescein-isothiocyanate-labeled dextran (FITC-dextran), in two groups of yellowfin tuna (Thunnus albacares). Red cell space was 13.8+/-0.7 ml kg-1 (mean +/- s.e.m.) Assuming a whole- body hematocrit...... for albacore (Thunnus alalunga, 82-197 ml kg-1). Plasma volume within the primary circulatory system (calculated from the 51Cr-labeled red blood cell data) was 32.9+/-2.3 ml kg-1. Dextran space was 37.0+/-3.7 ml kg-1. Because 500 kDa FITC-dextran appeared to remain within the vascular space, these data imply...

Optimized Li-Ion Electrolytes Containing Triphenyl Phosphate as a Flame-Retardant Additive

Science.gov (United States)

Smart, Marshall C.; Bugga, Ratnakumar V.; Prakash, G. K. Surya; Krause, Frederick C.

2011-01-01

A number of future NASA missions involving the exploration of the Moon and Mars will be human-rated and thus require high-specific-energy rechargeable batteries that possess enhanced safety characteristics. Given that Li-ion technology is the most viable rechargeable energy storage device for near-term applications, effort has been devoted to improving the safety characteristics of this system. There is also a strong desire to develop Li-ion batteries with improved safety characteristics for terrestrial applications, most notably for hybrid electric vehicle (HEV) and plug-in hybrid electric vehicle (PHEV) automotive applications. Therefore, extensive effort has been devoted recently to developing non-flammable electrolytes to reduce the flammability of the cells/battery. A number of electrolyte formulations have been developed, including systems that (1) incorporate greater concentrations of the flame-retardant additive (FRA); (2) use di-2,2,2-trifluoroethyl carbonate (DTFEC) as a co-solvent; (3) use 2,2,2- trifluoroethyl methyl carbonate (TFEMC); (4) use mono-fluoroethylene carbonate (FEC) as a co-solvent and/or a replacement for ethylene carbonate in the electrolyte mixture; and (5) utilize vinylene carbonate as a "SEI promoting" electrolyte additive, to build on the favorable results previously obtained. To extend the family of electrolytes developed under previous work, a number of additional electrolyte formulations containing FRAs, most notably triphenyl phosphate (TPP), were investigated and demonstrated in experimental MCMB (mesocarbon micro beads) carbon- LiNi(0.8)Co(0.2)O2 cells. The use of higher concentrations of the FRA is known to reduce the flammability of the electrolyte solution, thus, a concentration range was investigated (i.e., 5 to 20 percent by volume). The desired concentration of the FRA is the highest amount tolerable without adversely affecting the performance in terms of reversibility, ability to operate over a wide temperature range, and

Expansion of the cathode spot and generation of shock waves in the plasma of a volume discharge in atmospheric-pressure helium

International Nuclear Information System (INIS)

Omarov, O. A.; Kurbanismailov, V. S.; Arslanbekov, M. A.; Gadzhiev, M. Kh.; Ragimkhanov, G. B.; Al-Shatravi, Ali J. G.

2012-01-01

The expansion of the cathode spot and the generation of shock waves during the formation and development of a pulsed volume discharge in atmospheric-pressure helium were studied by analyzing the emission spectra of the cathode plasma and the spatiotemporal behavior of the plasma glow. The transition of a diffuse volume discharge in a centimeter-long gap into a high-current diffuse mode when the gas pressure increased from 1 to 5 atm and the applied voltage rose from the statistical breakdown voltage to a 100% overvoltage was investigated. Analytical expressions for the radius of the cathode spot and its expansion velocity obtained in the framework of a spherically symmetric model agree satisfactorily with the experimental data.

Atmospheric pressure microwave plasma system with ring waveguide

International Nuclear Information System (INIS)

Liu Liang; Zhang Guixin; Zhu Zhijie; Luo Chengmu

2007-01-01

Some scientists used waveguide as the cavity to produce a plasma jet, while large volume microwave plasma was relatively hard to get in atmospheric pressure. However, a few research institutes have already developed devices to generate large volume of atmospheric pressure microwave plasma, such as CYRANNUS and SLAN series, which can be widely applied. In this paper, present a microwave plasma system with ring waveguide to excite large volume of atmospheric pressure microwave plasma, plot curves on theoretical disruption electric field of some working gases, emulate the cavity through software, measure the power density to validate and show the appearance of microwave plasma. At present, large volume of argon and helium plasma have already been generated steadily by atmospheric pressure microwave plasma system. This research can build a theoretical basis of microwave plasma excitation under atmospheric pressure and will be useful in study of the device. (authors)

Formation of Reversible Solid Electrolyte Interface on Graphite Surface from Concentrated Electrolytes

Energy Technology Data Exchange (ETDEWEB)

Lu, Dongping; Tao, Jinhui; Yan, Pengfei; Henderson, Wesley A.; Li, Qiuyan; Shao, Yuyan; Helm, Monte L.; Borodin, Oleg; Graff, Gordon L.; Polzin, Bryant; Wang, Chong-Min; Engelhard, Mark; Zhang, Ji-Guang; De Yoreo, James J.; Liu, Jun; Xiao, Jie

2017-02-10

Interfacial phenomena have always been key determinants for the performance of energy storage technologies. The solid electrolyte interfacial (SEI) layer, pervasive on the surfaces of battery electrodes for numerous chemical couples, directly affects the ion transport, charge transfer and lifespan of the entire energy system. Almost all SEI layers, however, are unstable resulting in the continuous consumption of the electrolyte. Typically, this leads to the accumulation of degradation products on/restructuring of the electrode surface and thus increased cell impedance, which largely limits the long-term operation of the electrochemical reactions. Herein, a completely new SEI formation mechanism has been discovered, in which the electrolyte components reversibly self-assemble into a protective surface coating on a graphite electrode upon changing the potential. In contrast to the established wisdom regarding the necessity of employing the solvent ethylene carbonate (EC) to form a protective SEI layer on graphite, a wide range of EC-free electrolytes are demonstrated for the reversible intercalation/deintercalation of Li+ cations within a graphite lattice, thereby providing tremendous flexibility in electrolyte tailoring for battery couples. This novel finding is broadly applicable and provides guidance for how to control interfacial reactions through the relationship between ion aggregation and solvent decomposition at polarized interfaces.

Fluid and electrolyte homeostasis during spaceflight: Elucidation of mechanisms in a primate

Science.gov (United States)

Churchill, Susanne

1990-01-01

Although it is now well accepted that exposure to the hypogravic environment of space induces a shift of fluid from the lower extremities toward the upper body, the actual physiological responses to this central volume expansion have not been well characterized. Because it is likely that the fluid and electrolyte response to hypogravity plays a critical role in the development of Cardiovascular Deconditioning, elucidation of these mechanisms is of critical importance. The goal of flight experiment 223, scheduled to fly on SLS-2, is the definition of the basic renal, fluid and electrolyte response to spaceflight in four instrumented squirrel monkeys. The studies were those required to support the development of flight hardware and optimal inflight procedures, and to evaluate a ground-based model for weightlessness, lower body positive pressure (LBPP).

Production and loss of H- and D- in the volume of a plasma

International Nuclear Information System (INIS)

Hamilton, G.W.; Bacal, M.

1981-01-01

The study of the production and loss of negative ions, H - and D - , in the volume of a plasma has received considerable attention since the measurement of anomalously high densities of H - in 1977. The most probable mechanism for production is dissociative attachment (DA) to vibrationally highly-excited hydrogen molecules. New diagnostics developed for this purpose are photodetachment and the extension of coherent anti-Stokes Raman scattering (CARS) systems to the sensitivity required for low-pressure gases. Measurements and calculations indicate that the important loss mechanisms are diffusion to the walls at low densities and collisional destruction of several types at plasma densities above 10 10 cm -3 . Production mechanisms must be highly efficient to compete with the losses. It appears to be straightforward to extrapolate measurements and theory to the densities above 10 12 cm -3 that are required for an intense source of D - for neutral beam injection into magnetically-confined fusion devices

Production of a rapidly rotating plasma by cross-field injection of gun-produced plasma

International Nuclear Information System (INIS)

Ohzu, Akira; Ikehata, Takashi; Tanabe, Toshio; Mase, Hiroshi

1984-01-01

Cross-field plasma injection with use of a JxB plasma gun is described as a method to produce rapidly rotating plasma in a crossed electric and magnetic field system. The rotational velocity of the plasma is seriously limited by neutrals surrounding the plasma through strong interactions at the boundary layer. The concentration of neutrals can be reduced by the injection of fully or partially ionized plasma into the discharge volume instead of filling the volume with an operating gas. With use of this method, it is observed that the rotational velocity increases by a factor of 2 to 3 when compared with the conventional method of stationary gas-filling. (author)

A method for producing electrolyte and heat resistant drilling muds from bentonite clays

Energy Technology Data Exchange (ETDEWEB)

Koyev, K; Bedelcheva, A; Uzunova, I

1979-01-01

A method is developed for producing clay suspensions, which are resistant to electrolytes, high temperature and pressure, on the basis of bentonite clays with a high content of montmorillonite. The method is based on the subsequent introduction into the suspension of magnesium chloride (calcium chloride) and sodium chloride with intense mixing and maintenance of the high viscosity of the clay mass. The electrolytes are added in a specific order and volume: the magnesium chloride or calcium chloride at 1-3% and the sodium chloride at approximately 30%. The clay suspensions are characterized by high SNS and filtration (40 cm/sup 3/ in 30 min). The operational indicators may be regulated so that they remain in accordance with the required standards.

New polysaccharide-based polymer electrolytes; Nouveaux electrolytes polymeres a base de polysaccharides

Energy Technology Data Exchange (ETDEWEB)

Velasquez-Morales, P.; Le Nest, J.F.; Gandini, A. [Ecole Francaise de Papeterie et des Industries Graphique, 38 - Saint Martin d`Heres (France)

1996-12-31

Polysaccharides like cellulose and chitosan are known for their filmic properties. This paper concerns the synthesis and the study of chitosan-based polymer electrolytes. A preliminary work concerns the study of glucosamine reactivity. The poly-condensation of chitosan ethers (obtained by reaction with ethylene oxide or propylene oxide) with bifunctional and monofunctional oligo-ethers leads to the formation of thin lattices (10 {mu}m) having excellent mechanical properties. The presence of grafted polyether chains along the polysaccharide skeleton allows to modify the vitreous transition temperature and the molecular disorder of the system. Two type of polymer electrolytes have been synthesized: electrolytes carrying a dissolved alkaline metal salt and ionomers. The analysis of their thermal, dynamical mechanical, nuclear magnetic relaxation, electrical, and electrochemical properties shows that this new class of polymer electrolytes has the same performances as ethylene poly-oxide based amorphous lattices plus the advantage of having good filmic properties. Abstract only. (J.S.)

New polysaccharide-based polymer electrolytes; Nouveaux electrolytes polymeres a base de polysaccharides

Energy Technology Data Exchange (ETDEWEB)

Velasquez-Morales, P; Le Nest, J F; Gandini, A [Ecole Francaise de Papeterie et des Industries Graphique, 38 - Saint Martin d` Heres (France)

1997-12-31

Polysaccharides like cellulose and chitosan are known for their filmic properties. This paper concerns the synthesis and the study of chitosan-based polymer electrolytes. A preliminary work concerns the study of glucosamine reactivity. The poly-condensation of chitosan ethers (obtained by reaction with ethylene oxide or propylene oxide) with bifunctional and monofunctional oligo-ethers leads to the formation of thin lattices (10 {mu}m) having excellent mechanical properties. The presence of grafted polyether chains along the polysaccharide skeleton allows to modify the vitreous transition temperature and the molecular disorder of the system. Two type of polymer electrolytes have been synthesized: electrolytes carrying a dissolved alkaline metal salt and ionomers. The analysis of their thermal, dynamical mechanical, nuclear magnetic relaxation, electrical, and electrochemical properties shows that this new class of polymer electrolytes has the same performances as ethylene poly-oxide based amorphous lattices plus the advantage of having good filmic properties. Abstract only. (J.S.)

Study of electrolytic reduction of uranium VI to uranium IV in nitrate systems

Energy Technology Data Exchange (ETDEWEB)

Araujo, B.F. de; Almeida, S.G. de; Forbicini, S; Matsuda, H T; Araujo, J.A. de [Instituto de Pesquisas Energeticas e Nucleares, Sao Paulo (Brazil). Centro de Engenharia Quimica

1980-01-01

Experimental parameters are optimized in order to obtain uranium (IV) nitrate solutions at maximum yield, using hydrazine as stabilizer. Uranium (VI) electrolytic reduction was chosen because: there is no increase in the volume of radioactive effluents; there are no secondary reactions; there is no need for further separations; all reagents used are not inflammable. The method is, therefore, efficient and of low cost.

Polymer Electrolytes for Lithium/Sulfur Batteries

Directory of Open Access Journals (Sweden)

The Nam Long Doan

2012-08-01

Full Text Available This review evaluates the characteristics and advantages of employing polymer electrolytes in lithium/sulfur (Li/S batteries. The main highlights of this study constitute detailed information on the advanced developments for solid polymer electrolytes and gel polymer electrolytes, used in the lithium/sulfur battery. This includes an in-depth analysis conducted on the preparation and electrochemical characteristics of the Li/S batteries based on these polymer electrolytes.

Analysis on the effect of polysulfide electrolyte composition for higher performance of Si quantum dot-sensitized solar cells

International Nuclear Information System (INIS)

Seo, Hyunwoong; Wang, Yuting; Uchida, Giichiro; Kamataki, Kunihiro; Itagaki, Naho; Koga, Kazunori; Shiratani, Masaharu

2013-01-01

Quantum dot-sensitized solar cell (QDSC) based on multiple exciton generation of QD has been expected to realize high efficiency. This work focused on Si QD instead of conventional QD materials because of their toxicity and scarcity. Si QDs were fabricated by multi-hollow discharge plasma chemical vapor deposition. General QDSCs use polysulfide electrolyte because it is suitable for stabilizing QDs and its redox reaction is the best as compared with other redox systems. The improvement of redox reaction which is one of the slowest reactions in the kinetic analysis is closely connected with the enhancement of performance. For the enhancement on the overall performance of Si QDSC, the performance dependence on electrolyte composition was investigated. The concentrations of Na 2 S and S were varied for the activation of redox reaction and KCl concentration was optimized for the improvement of electrolyte characteristics. Consequently, the best performance of Si QDSC was obtained with 1 M Na 2 S, 2 M S, and 0.4 M KCl polysulfide electrolyte

Solid polymer electrolyte from phosphorylated chitosan

Energy Technology Data Exchange (ETDEWEB)

Fauzi, Iqbal, E-mail: arcana@chem.itb.ac.id; Arcana, I Made, E-mail: arcana@chem.itb.ac.id [Inorganic and Physical Chemistry Research Groups, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia)

2014-03-24

Recently, the need of secondary battery application continues to increase. The secondary battery which using a liquid electrolyte was indicated had some weakness. A solid polymer electrolyte is an alternative electrolytes membrane which developed in order to replace the liquid electrolyte type. In the present study, the effect of phosphorylation on to polymer electrolyte membrane which synthesized from chitosan and lithium perchlorate salts was investigated. The effect of the component’s composition respectively on the properties of polymer electrolyte, was carried out by analyzed of it’s characterization such as functional groups, ion conductivity, and thermal properties. The mechanical properties i.e tensile resistance and the morphology structure of membrane surface were determined. The phosphorylation processing of polymer electrolyte membrane of chitosan and lithium perchlorate was conducted by immersing with phosphoric acid for 2 hours, and then irradiated on a microwave for 60 seconds. The degree of deacetylation of chitosan derived from shrimp shells was obtained around 75.4%. Relative molecular mass of chitosan was obtained by viscometry method is 796,792 g/mol. The ionic conductivity of chitosan membrane was increase from 6.33 × 10{sup −6} S/cm up to 6.01 × 10{sup −4} S/cm after adding by 15 % solution of lithium perchlorate. After phosphorylation, the ionic conductivity of phosphorylated lithium chitosan membrane was observed 1.37 × 10{sup −3} S/cm, while the tensile resistance of 40.2 MPa with a better thermal resistance. On the strength of electrolyte membrane properties, this polymer electrolyte membrane was suggested had one potential used for polymer electrolyte in field of lithium battery applications.

Changes in Peak Oxygen Uptake and Plasma Volume in Fit and Unfit Subjects Following Exposure to a Simulation of Microgravity

National Research Council Canada - National Science Library

Convertino, Victor

1997-01-01

To test the hypothesis that the magnitude of reduction in plasma volume and work capacity following exposure to simulated microgravity is dependent on the initial level of aerobic fitness, peak oxygen uptake (VO2peak...

BFR Electrolyte Additive Safety and Flammability Characterization

Energy Technology Data Exchange (ETDEWEB)

Allcorn, Eric [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-10-13

Lithium-ion battery safety is a critical issue in the adoption of the chemistry to larger scale applications such as transportation and stationary storage. One of the critical components impacting the safety of lithium-ion batteries is their use of highly flammable organic electrolytes. In this work, brominated flame retardants (BFR’s) – an existing class of flame retardant materials – are incorporated as additives to lithium-ion battery electrolytes with the intention to reduce the electrolyte flammability and thereby improve safety. There are a few critical needs for a successful electrolyte additive: solubility in the electrolyte, electrochemical stability over the range of battery operation, and minimal detrimental effects on battery performance. Those detrimental effects can take the form of electrolyte specific impacts, such as a reduction in conductivity, or electrode impacts, such as SEI-layer modification or chemical instability to the active material. In addition to these needs, the electrolyte additive also needs to achieve its intended purpose, which in this case is to reduce the flammability of the electrolyte. For the work conducted as part of this SPP agreement three separate BFR materials were provided by Albemarle to be tested by Sandia as additives in a traditional lithium-ion battery electrolyte. The provided BFR materials were tribromo-neopentyl alcohol, tetrabromo bisphenol A, and tribromoethylene. These materials were incorporated as separate 4 wt.% additives into a traditional lithium-ion battery electrolyte and compared to said traditional electrolyte, designated Gen2.

Multivalent weak electrolytes - risky background electrolytes for capillary zone electrophoresis

Czech Academy of Sciences Publication Activity Database

Beckers, J. L.; Boček, Petr

2002-01-01

Roč. 23, č. 12 (2002), s. 1942-1946 ISSN 0173-0835 R&D Projects: GA ČR GA203/99/0044; GA ČR GA203/02/0023; GA ČR GA203/01/0401; GA AV ČR IAA4031703; GA AV ČR IAA4031103 Institutional research plan: CEZ:AV0Z4031919 Keywords : background electrolytes * capillary zone electrophoresis * multivalent electrolytes Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.325, year: 2002

Electrolyte Additives for Phosphoric Acid Fuel Cells

DEFF Research Database (Denmark)

Gang, Xiao; Hjuler, H.A.; Olsen, C.A.

1993-01-01

, as a fuel-cell performance with the modified electrolytes. Specific conductivity measurements of some of the modified phosphoric acid electrolytes are reported. At a given temperature, the conductivity of the C4F9SO3K-modified electrolyte decreases with an increasing amount of the additive; the conductivity...... of the remains at the same value as the conductivity of the pure phosphoric acid. At a given composition, the conductivity of any modified electrolyte increases with temperature. We conclude that the improved cell performance for modified electrolytes is not due to any increase in conductivity.......Electrochemical characteristics of a series of modified phosphoric acid electrolytes containing fluorinated car on compounds and silicone fluids as additives are presented. When used in phosphoric acid fuel cells, the modified electrolytes improve the performance due to the enhanced oxygen...

High Lithium Transference Number Electrolytes via Creation of 3-Dimensional, Charged, Nanoporous Networks from Dense Functionalized Nanoparticle Composites

KAUST Repository

Schaefer, Jennifer L.

2013-03-26

High lithium transference number, tLi+, electrolytes are desired for use in both lithium-ion and lithium metal rechargeable battery technologies. Historically, low tLi+ electrolytes have hindered device performance by allowing ion concentration gradients within the cell, leading to high internal resistances that ultimately limit cell lifetime, charging rates, and energy density. Herein, we report on the synthesis and electrochemical features of electrolytes based on nanoparticle salts designed to provide high tLi+. The salts are created by cofunctionalization of metal oxide nanoparticles with neutral organic ligands and tethered lithium salts. When dispersed in a conducting fluid such as tetraglyme, they spontaneously form a charged, nanoporous network of particles at moderate nanoparticle loadings. Modification of the tethered anion chemistry from -SO3 - to -SO3BF3 - is shown to enhance ionic conductivity of the electrolytes by facilitating ion pair dissociation. At a particle volume fraction of 0.15, the electrolyte exists as a self-supported, nanoporous gel with an optimum ionic conductivity of 10 -4 S/cm at room temperature. Galvanostatic polarization measurements on symmetric lithium metal cells containing the electrolyte show that the cell short circuit time, tSC, is inversely proportional to the square of the applied current density tSC ∼ J-2, consistent with previously predicted results for traditional polymer-in-salt electrolytes with low tLi+. Our findings suggest that electrolytes with tLi+ ≈ 1 and good ion-pair dissociation delay lithium dendrite nucleation and may lead to improved lithium plating in rechargeable batteries with metallic lithium anodes. © 2013 American Chemical Society.

Aspects of industrial production of solid electrolyte fuel cells (SOFC) by thermal spraying technology; Aspekte industrieller Fertigung von Festelektrolyt-Brennstoffzellen (SOFC) mittels thermischer Beschichtungsverfahren

Energy Technology Data Exchange (ETDEWEB)

Weckmann, Hannes

2010-07-01

The present thesis deals with measures to optimize the large-volume production of Solid Oxide Fuel Cells (SOFC) based on thermal spraying technology. Based on the well-established Vacuum Plasma Spraying (VPS) at DLR the potential of alternative thermal spraying techniques as well as alternative base materials was investigated in order to deposit SOFC-anode, electrolyte and insulating layers. Production costs, reproducibility and long-term stability of the production process as well as the fuel cell performance were major target criteria. Depending on the parameter set applied when using the cost efficient Atmospheric Plasma Spraying (APS) in combination with Nickel-Graphite as base material a significant improvement of gas permeability and electrical conductivity was achieved in comparison to the VPS sprayed reference anode. The power density of a fuel cell with an APS-Nickel-Graphite anode (184 mW/cm{sup 2}) was slightly better than the performance with a VPS reference anode (159 mW/cm{sup 2}). In comparison to the VPS process, ceramic electrolyte layers of fully stabilized Zirconia (YSZ) with significantly higher gas tightness could be demonstrated when high energy processes such as Low Pressure Plasma Spraying (LPPS). Thin-film Low Pressure Plasma Spraying (LPPS-Thin-film) and High Velocity Oxy Fuel Spraying (HVOF) were applied. The power density of a fuel cell equipped with an HVOF electrolyte was significantly improved to 234 mW/cm{sup 2} as compared to 187 mW/cm{sup 2} with the VPS sprayed reference cell. Further improvement of the power density was achieved with an LPPS-electrolyte (273 mW/cm{sup 2}). HVOF and VPS sprayed layers of pure Spinel in composite with metallic active braze (equivalent to the sealing between individual layers in the fuel cell stack) could exceed the demanded charge transfer resistance of >1 k{omega}cm{sup 2} at 800 C operating temperature only in few cases. When blended base powder of Spinel and Magnesia in combination with the VPS

Molecular motion in polymer electrolytes. An investigation of methods for improving the conductivity of solid polymer electrolytes

International Nuclear Information System (INIS)

Webster, Mark Ian

2002-01-01

Three methods were explored with a view to enhancing the ionic conductivity of polymer electrolytes; namely the addition of an inert, inorganic filler, the addition of a plasticizer and the incorporation of the electrolyte in the pores of silica matrices. There have been a number of reports, which suggest the addition of nanocrystalline oxides to polymer electrolytes increases the ionic conductivities by about a factor of two. In this thesis studies of the polymer electrolyte NaSCN.P(EO) 8 with added nanocrystalline alumina powder are reported which show no evidence of enhanced conductivity. The addition of a plasticizer to polymer electrolytes will increase the ionic conductivity. A detailed study was made of the polymer electrolytes LiT.P(EO) 10 and LiClO 4 .P(EO) 10 with added ethylene carbonate plasticizer. The conductivities showed an enhancement, however this disappeared on heating under vacuum. The present work suggests that the plasticised system is not thermodynamically stable and will limit the applications of the material. A series of samples were prepared from the polymer electrolyte LiT.P(EO) 8 and a range of porous silicas. The silicas were selected to give a wide range of pore size and included Zeolite Y, ZSM5, mesoporous silica and a range of porous glasses. This gave pore sizes from less than one nm to 50 nm. A variety of experiments, including X-ray diffraction, DSC and NMR, showed that the polymer electrolyte entered to pores of the silica. As a result the polymer was amorphous and the room temperature conductivity was enhanced. The high temperature conductivity was not increased above that for the pure electrolyte. The results suggest that this could be employed in applications, however would require higher conducting electrolytes to be of practical benefit. (author)

Electrolytic method to make alkali alcoholates using ion conducting alkali electrolyte/separator

Science.gov (United States)

Joshi, Ashok V [Salt Lake City, UT; Balagopal, Shekar [Sandy, UT; Pendelton, Justin [Salt Lake City, UT

2011-12-13

Alkali alcoholates, also called alkali alkoxides, are produced from alkali metal salt solutions and alcohol using a three-compartment electrolytic cell. The electrolytic cell includes an anolyte compartment configured with an anode, a buffer compartment, and a catholyte compartment configured with a cathode. An alkali ion conducting solid electrolyte configured to selectively transport alkali ions is positioned between the anolyte compartment and the buffer compartment. An alkali ion permeable separator is positioned between the buffer compartment and the catholyte compartment. The catholyte solution may include an alkali alcoholate and alcohol. The anolyte solution may include at least one alkali salt. The buffer compartment solution may include a soluble alkali salt and an alkali alcoholate in alcohol.

Effects of plasma electrolytic oxidation process on the mechanical properties of additively manufactured porous biomaterials.

Science.gov (United States)

Gorgin Karaji, Zahra; Hedayati, Reza; Pouran, Behdad; Apachitei, Iulian; Zadpoor, Amir A

2017-07-01

Metallic porous biomaterials are recently attracting more attention thanks to the additive manufacturing techniques which help produce more complex structures as compared to conventional techniques. On the other hand, bio-functional surfaces on metallic biomaterials such as titanium and its alloys are necessary to enhance the biological interactions with the host tissue. This study discusses the effect of plasma electrolytic oxidation (PEO), as a surface modification technique to produce bio-functional layers, on the mechanical properties of additively manufactured Ti6Al4V scaffolds based on the cubic unit cell. For this purpose, the PEO process with two different oxidation times was applied on scaffolds with four different values of relative density. The effects of the PEO process were studied by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), optical microscopy as well as static and dynamic (fatigue) mechanical testing under compression. SEM results indicated pore formation on the surface of the scaffolds after oxidation with a thickness of 4.85±0.36μm of the oxide layer after 2min and 9.04±2.27μm after 5min oxidation (based on optical images). The static test results showed the high effect of relative density of porous structure on its mechanical properties. However, oxidation did not influence most of the mechanical properties such as maximum stress, yield stress, plateau stress, and energy absorption, although its effect on the elastic modulus was considerable. Under fatigue loading, none of the scaffolds failed even after 10 6 loading cycles at 70% of their yield stress. Copyright © 2017 Elsevier B.V. All rights reserved.

Carbogen Breathing Differentially Enhances Blood Plasma Volume and 5-Fluorouracil Uptake in Two Murine Colon Tumor Models with a Distinct Vascular Structure

Directory of Open Access Journals (Sweden)

Hanneke W.M. van Laarhoven

2006-06-01

Full Text Available For the systemic treatment of colorectal cancer, 5-fluorouracil (FU-based chemotherapy is the standard. However, only a subset of patients responds to chemotherapy. Breathing of carbogen (95% O2 and 5% CO2 may increase the uptake of FU through changes in tumor physiology. This study aims to monitor in animal models in vivo the effects of carbogen breathing on tumor blood plasma volume, pH, and energy status, and on FU uptake and metabolism in two colon tumor models C38 and C26a, which differ in their vascular structure and hypoxic status. Phosphorus-31 magnetic resonance spectroscopy (MRS was used to assess tumor pH and energy status, and fluorine-19 MRS was used to follow FU uptake and metabolism. Advanced magnetic resonance imaging methods using ultrasmall particles of iron oxide were performed to assess blood plasma volume. The results showed that carbogen breathing significantly decreased extracellular pH and increased tumor blood plasma volume and FU uptake in tumors. These effects were most significant in the C38 tumor line, which has the largest relative vascular area. In the C26a tumor line, carbogen breathing increased tumor growth delay by FU. In this study, carbogen breathing also enhanced systemic toxicity by FU.

Influence of Electrolyte Chemistry on Morphology and Corrosion Resistance of Micro Arc Oxidation Coatings Deposited on Magnesium

Science.gov (United States)

Rama Krishna, L.; Poshal, G.; Sundararajan, G.

2010-12-01

In the present work, micro arc oxidation (MAO) coatings were synthesized on magnesium substrate employing 11 different electrolyte compositions containing systematically varied concentrations of sodium silicate (Na2SiO3), potassium hydroxide (KOH), and sodium aluminate (NaAlO2). The resultant coatings were subjected to coating thickness measurement, energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), image analysis, and three-dimensional (3-D) optical profilometry. The corrosion performance of the coatings was evaluated by conducting potentiodynamic polarization tests in 3.5 wt pct NaCl solution. The inter-relationships between the electrolyte chemistry and the resulting chemistry and porosity of the coating, on one hand, and with the aqueous corrosion behavior of the coating, on the other, were studied. The changes in pore morphology and pore distribution in the coatings were found to be significantly influenced by the electrolyte composition. The coatings can have either through-thickness pores or pores in the near surface region alone depending on the electrolyte composition. The deleterious role of KOH especially when its concentration is >20 pct of total electrolyte constituents promoting the formation of large and deep pores in the coating was demonstrated. A reasonable correlation indicating the increasing pore volume implying the increased corrosion was noticed.

Electrolytes for lithium and lithium-ion batteries

CERN Document Server

Jow, T Richard; Borodin, Oleg; Ue, Makoto

2014-01-01

Electrolytes for Lithium and Lithium-ion Batteries provides a comprehensive overview of the scientific understanding and technological development of electrolyte materials in the last?several years. This book covers key electrolytes such as LiPF6 salt in mixed-carbonate solvents with additives for the state-of-the-art Li-ion batteries as well as new electrolyte materials developed recently that lay the foundation for future advances.?This book also reviews the characterization of electrolyte materials for their transport properties, structures, phase relationships, stabilities, and impurities.

Plasma diagnostics package. Volume 2: Spacelab 2 section. Part B: Thesis projects. Final science report

International Nuclear Information System (INIS)

Pickett, J.S.; Frank, L.A.; Kurth, W.S.

1988-06-01

This volume (2), which consists of two parts (A and B), of the Plasma Diagnostics Package (PDP) Final Science Report contains a summary of all of the data reduction and scientific analyses which were performed using PDP data obtained on STS-51F as a part of the Spacelab 2 (SL-2) payload. This work was performed during the period of launch, July 29, 1985, through June 30, 1988. During this period the primary data reduction effort consisted of processing summary plots of the data received by 12 of the 14 instruments located on the PDP and submitting these data to the National Space Science Data Center (NSSDC). Three Master's and three Ph.D. theses were written using PDP instrumentation data. These theses are listed in Volume 2, Part B

Blood volume studies

International Nuclear Information System (INIS)

Lewis, S.M.; Yin, J.A.L.

1986-01-01

The use of dilution analysis with such radioisotopes as 51 Cr, 32 P, sup(99m)Tc and sup(113m)In for measuring red cell volume is reviewed briefly. The use of 125 I and 131 I for plasma volume studies is also considered and the subsequent determination of total blood volume discussed, together with the role of the splenic red cell volume. Substantial bibliography. (UK)

Enhancing Electrochemical Performance of Graphene Fiber-Based Supercapacitors by Plasma Treatment.

Science.gov (United States)

Meng, Jie; Nie, Wenqi; Zhang, Kun; Xu, Fujun; Ding, Xin; Wang, Shiren; Qiu, Yiping

2018-04-25

Graphene fiber-based supercapacitors (GFSCs) hold high power density, fast charge-discharge rate, ultralong cycling life, exceptional mechanical/electrical properties, and safe operation conditions, making them very promising to power small wearable electronics. However, the electrochemical performance is still limited by the severe stacking of graphene sheets, hydrophobicity of graphene fibers, and complex preparation process. In this work, we develop a facile but robust strategy to easily enhance electrochemical properties of all-solid-state GFSCs by simple plasma treatment. We find that 1 min plasma treatment under an ambient condition results in 33.1% enhancement of areal specific capacitance (36.25 mF/cm 2 ) in comparison to the as-prepared GFSC. The energy density reaches 0.80 μW h/cm 2 in polyvinyl alcohol/H 2 SO 4 gel electrolyte and 18.12 μW h/cm 2 in poly(vinylidene difluoride)/ethyl-3-methylimidazolium tetrafluoroborate electrolyte, which are 22 times of that of as-prepared ones. The plasma-treated GFSCs also exhibit ultrahigh rate capability (69.13% for 40 s plasma-treated ones) and superior cycle stability (96.14% capacitance retention after 20 000 cycles for 1 min plasma-treated ones). This plasma strategy can be extended to mass-manufacture high-performance carbonaceous fiber-based supercapacitors, such as graphene and carbon nanotube-based ones.

Mechanistic Study of Electrolyte Additives to Stabilize High-Voltage Cathode–Electrolyte Interface in Lithium-Ion Batteries

Energy Technology Data Exchange (ETDEWEB)

Gao, Han [Chemical; Maglia, Filippo [BMW Group, Munich 80788, Germany; Lamp, Peter [BMW Group, Munich 80788, Germany; Amine, Khalil [Chemical; Chen, Zonghai [Chemical

2017-12-13

Current developments of electrolyte additives to stabilize electrode-electrolyte interface in Li-ion batteries highly rely on a trial-and-error search, which involves repetitive testing and intensive amount of resources. The lack of understandings on the fundamental protection mechanisms of the additives significantly increases the difficulty for the transformational development of new additives. In this study, we investigated two types of individual protection routes to build a robust cathode-electrolyte interphase at high potentials: (i) a direct reduction in the catalytic decomposition of the electrolyte solvent; and (ii) formation of a “corrosion inhibitor film” that prevents severely attack and passivation from protons that generated from the solvent oxidation, even the decomposition of solvent cannot not mitigated. Effect of three exemplary electrolyte additives: (i) lithium difluoro(oxalato)borate (LiDFOB); (ii) 3-hexylthiophene (3HT); and (iii) tris(hexafluoro-iso-propyl)phosphate (HFiP), on LiNi0.6Mn0.2Co0.2O2 (NMC 622) cathode were investigated to validate our hypothesis. It is demonstrated that understandings of both electrolyte additives and solvent are essential and careful balance between the cathode protection mechanism of additives and their side effects is critical to obtain optimum results. More importantly, this study opens up new directions of rational design of functional electrolyte additives for the next generation high-energy density lithium-ion chemistries.

Characterization of Porous Phosphate Coatings Enriched with Magnesium or Zinc on CP Titanium Grade 2 under DC Plasma Electrolytic Oxidation

Directory of Open Access Journals (Sweden)

Krzysztof Rokosz

2018-02-01

Full Text Available The aim of the paper is to study and determine the effect of voltage increasing from 500 up to 650 VDC on chemical and electrochemical properties of the obtained porous coatings with plasma electrolytic oxidation (PEO processes, known also as micro arc oxidation (MAO. In the present paper, the chemical and electrochemical characterization of porous phosphate coatings enriched with magnesium or zinc on commercially pure (CP Titanium Grade 2 under DC-PEO obtained in electrolytes based on concentrated 85% analytically pure H3PO4 (98 g/mole acid with additions of 500 g·L−1 of zinc nitrate Zn(NO32∙6H2O or magnesium nitrate Mg(NO32∙6H2O, are described. These materials were characterized using scanning electron microscope (SEM with energy-dispersive X-ray spectroscopy (EDS, X-ray photoelectron spectroscopy (XPS and glow discharge optical emission spectroscopy (GDOES. It was found that the voltage of PEO process has influence on the chemical composition and thickness of the obtained porous coatings as well as on their electrochemical behavior. The higher the potential of PEO treatment, the higher the amount of zinc-to-phosphorus ratio for zinc enriched coatings was obtained, whereas in magnesium enriched coatings, the average amount of magnesium detected in PEO coating is approximately independent of the PEO voltages. Based on XPS studies, it was found out that most likely the top 10 nm of porous coatings is constructed of titanium (Ti4+, magnesium (Mg2+, zinc (Zn2+, and phosphates PO43− and/or HPO42− and/or H2PO4− and/or P2O74−. On the basis of GDOES studies, a four-sub-layer model of PEO coatings is proposed. Analysis of the potentiodynamic corrosion curves allowed to conclude that the best electrochemical repeatability was noted for magnesium and zinc enriched coatings obtained at 575 VDC.

Interplay Between Structure and Conductivity in 1-Ethyl-3-methylimidazolium tetrafluoroborate/(δ-MgCl2)f Electrolytes for Magnesium Batteries

International Nuclear Information System (INIS)

Bertasi, Federico; Vezzù, Keti; Nawn, Graeme; Pagot, Gioele; Di Noto, Vito

2016-01-01

The synthesis, physicochemical properties and conductivity mechanism of a family of ionic liquid-based electrolytes for use in secondary Mg batteries are reported. The electrolytes are obtained by dissolving controlled amounts of δ-MgCl 2 salt into the ionic liquid (IL) 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF 4 ) which acts as a solvent. δ-MgCl 2 consists of an inorganic ribbon of Mg atoms covalently bonded together through bridging chlorine atoms. Due to this peculiar structural motif, with respect to the electrolytes based on conventional Mg salts, it is possible to achieve electrolytes of higher Mg concentration. Thus, concatenated anionic complexes bridged via halogen atoms are formed, improving the electrochemical performance of these materials. Electrolytes with a general formula EMImBF 4 /(δ-MgCl 2 ) f with f ranging from 0 to 0.117 are obtained. The composition of the obtained materials is determined by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). The properties of these systems are investigated by means of Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and vibrational spectroscopy in both medium (MIR) and far infrared (FIR). Finally, Broadband Electrical Spectroscopy (BES) is carried out with the aim to elucidate the electrical response of the electrolytes in terms of their polarization and relaxation phenomena and to propose a conductivity mechanism. At 20 °C the highest conductivity (0.007 S/cm) is observed for the electrolyte with c Mg = 0.00454 mol Mg /kg IL .

Surface Charge at the Oxide/Electrolyte Interface: Toward Optimization of Electrolyte Composition for Treatment of Aluminum and Magnesium by Plasma Electrolytic Oxidation

Czech Academy of Sciences Publication Activity Database

Nominé, A.; Martin, J.; Noël, C.; Henrion, G.; Belmonte, T.; Bardin, I.V.; Lukeš, Petr

2016-01-01

Roč. 32, č. 5 (2016), s. 1405-1409 ISSN 0743-7463 Institutional support: RVO:61389021 Keywords : corrosion-resistance * Mg-alloy * cotings * layers * microstructure * porosity * points Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.833, year: 2016

ZnTe Semiconductor-Polymer Gel Composited Electrolyte for Conversion of Solar Energy

Directory of Open Access Journals (Sweden)

Wonchai Promnopas

2014-01-01

Full Text Available Nanostructured cubic p-type ZnTe for dye sensitized solar cells (DSSCs was synthesized from 1 : 1 molar ratio of Zn : Te by 600 W and 900 W microwave plasma for 30 min. In this research, their green emissions were detected at the same wavelengths of 563 nm, the energy gap (Eg at 2.24 eV, and three Raman shifts at 205, 410, and 620 cm−1. The nanocomposited electrolyte of quasisolid state ZnO-DSSCs was in correlation with the increase in the JSC, VOC, fill factor (ff, and efficiency (η by increasing the wt% of ZnTe-GPE (gel polymer electrolyte to an optimum value and decreased afterwards. The optimal ZnO-DSSC performance was achieved for 0.20 wt% ZnTe-GPE with the highest photoelectronic energy conversion efficiency at 174.7% with respect to that of the GPE without doping of p-type ZnTe.

Non-aqueous electrolytes for lithium ion batteries

Science.gov (United States)

Chen, Zonghai; Amine, Khalil

2015-11-12

The present invention is generally related to electrolytes containing anion receptor additives to enhance the power capability of lithium-ion batteries. The anion receptor of the present invention is a Lewis acid that can help to dissolve LiF in the passivation films of lithium-ion batteries. Accordingly, one aspect the invention provides electrolytes comprising a lithium salt; a polar aprotic solvent; and an anion receptor additive; and wherein the electrolyte solution is substantially non-aqueous. Further there are provided electrochemical devices employing the electrolyte and methods of making the electrolyte.

Drug delivery device including electrolytic pump

KAUST Repository

Foulds, Ian G.; Buttner, Ulrich; Yi, Ying

2016-01-01

Systems and methods are provided for a drug delivery device and use of the device for drug delivery. In various aspects, the drug delivery device combines a “solid drug in reservoir” (SDR) system with an electrolytic pump. In various aspects an improved electrolytic pump is provided including, in particular, an improved electrolytic pump for use with a drug delivery device, for example an implantable drug delivery device. A catalytic reformer can be incorporated in a periodically pulsed electrolytic pump to provide stable pumping performance and reduced actuation cycle.

Drug delivery device including electrolytic pump

KAUST Repository

Foulds, Ian G.

2016-03-31

Systems and methods are provided for a drug delivery device and use of the device for drug delivery. In various aspects, the drug delivery device combines a “solid drug in reservoir” (SDR) system with an electrolytic pump. In various aspects an improved electrolytic pump is provided including, in particular, an improved electrolytic pump for use with a drug delivery device, for example an implantable drug delivery device. A catalytic reformer can be incorporated in a periodically pulsed electrolytic pump to provide stable pumping performance and reduced actuation cycle.

Electrolyte chemistry control in electrodialysis processing

Science.gov (United States)

Hayes, Thomas D.; Severin, Blaine F.

2017-12-26

Methods for controlling electrolyte chemistry in electrodialysis units having an anode and a cathode each in an electrolyte of a selected concentration and a membrane stack disposed therebetween. The membrane stack includes pairs of cationic selective and anionic membranes to segregate increasingly dilute salts streams from concentrated salts stream. Electrolyte chemistry control is via use of at least one of following techniques: a single calcium exclusionary cationic selective membrane at a cathode cell boundary, an exclusionary membrane configured as a hydraulically isolated scavenger cell, a multivalent scavenger co-electrolyte and combinations thereof.

Conductivity studies of PEG based polymer electrolyte for applications as electrolyte in ion batteries

Science.gov (United States)

Patil, Ravikumar V.; Praveen, D.; Damle, R.

2018-05-01

Development of lithium ion batteries employing solid polymer electrolytes as electrolyte material has led to efficient energy storage and usage in many portable devices. However, due to a few drawbacks like lower ionic conductivity of solid polymer electrolytes (SPEs), studies on SPEs for improvement in conductivity still have a good scope. In the present paper, we report the conductivity studies of a new SPE with low molecular weight poly ethylene glycol (PEG) as host polymer in which a salt with larger anion Lithium trifluro methane sulphonate (LTMS). XRD studies have revealed that the salt completely dissociates in the polymer giving a good stable electrolyte at lower salt concentration. Conductivity of the SPEs has been studied as a function of temperature and we reiterate that the conductivity is a thermally activated process and follows Arrhenius type behavior.

Characterization and formation of hydroxyapatite on Ti6Al4V coated by plasma electrolytic oxidation

International Nuclear Information System (INIS)

Durdu, Salih; Deniz, Ömer Faruk; Kutbay, Işıl; Usta, Metin

2013-01-01

Highlights: ► Ti6Al4V alloys were coated by PEO in calcium acetate and β-calcium glycerophosphate. ► Hydroxyapatite and calcium apatite based phases were directly formed on Ti6Al4V. ► Hydroxyapatite coatings were characterized systematically for different times. ► After 5 min, hydroxyapatite and calcium based phases begin to form on the coating. ► HAp on the coating is amorphous due to the rapid solidification during PEO. - Abstract: In this study, Ti6Al4V alloy was coated in the solution consisting of calcium acetate (CA) and β-calcium glycerophosphate (β-Ca-GP) by plasma electrolytic oxidation (PEO) to produce hydroxyapatite and calcium apatite-based composite used as of bioactive and biocompatible materials in biomedical applications. The phase structures, surface morphologies, functional groups of molecules, chemical compositions of the surfaces and the binding energies of atoms in the coating were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS), respectively. Anatase, rutile, calcium oxide, titanium phosphide, whitlockite, tri-calcium phosphate (TCP), perovskite calcium titanate and hydroxyapatite phases on the coating were detected by XRD analysis. The surface of coatings produced by PEO method has a porous structure. The amount of amorphous hydroxyapatite is the highest value for the coating produced at 5 min in XPS and ATR-FTIR results, whereas the amount of crystalline hydroxyapatite has the highest value for coating produced at 120 min in XRD results.

Atmospheric Gaseous Plasma with Large Dimensions

Science.gov (United States)

Korenev, Sergey

2012-10-01

The forming of atmospheric plasma with large dimensions using electrical discharge typically uses the Dielectric Barrier Discharge (DBD). The study of atmospheric DBD was shown some problems related to homogeneous volume plasma. The volume of this plasma determines by cross section and gas gap between electrode and dielectric. The using of electron beam for volume ionization of air molecules by CW relativistic electron beams was shown the high efficiency of this process [1, 2]. The main advantage of this approach consists in the ionization of gas molecules by electrons in longitudinal direction determines by their kinetic energy. A novel method for forming of atmospheric homogeneous plasma with large volume dimensions using ionization of gas molecules by pulsed non-relativistic electron beams is presented in the paper. The results of computer modeling for delivered doses of electron beams in gases and ionization are discussed. The structure of experimental bench with plasma diagnostics is considered. The preliminary results of forming atmospheric plasma with ionization gas molecules by pulsed nanosecond non-relativistic electron beam are given. The analysis of potential applications for atmospheric volume plasma is presented. Reference: [1] S. Korenev. ``The ionization of air by scanning relativistic high power CW electron beam,'' 2002 IEEE International Conference on Plasma Science. May 2002, Alberta, Canada. [2] S. Korenev, I. Korenev. ``The propagation of high power CW scanning electron beam in air.'' BEAMS 2002: 14th International Conference on High-Power Particle Beams, Albuquerque, New Mexico (USA), June 2002, AIP Conference Proceedings Vol. 650(1), pp. 373-376. December 17.

Influence of chloride ion concentration on the electrochemical corrosion behaviour of plasma electrolytic oxidation coated AM50 magnesium alloy

International Nuclear Information System (INIS)

Liang, J.; Srinivasan, P. Bala; Blawert, C.; Dietzel, W.

2010-01-01

The electrochemical degradation of a silicate- and a phosphate-based plasma electrolytic oxidation (PEO) coated AM50 magnesium alloy obtained using a pulsed DC power supply was investigated using potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) in NaCl solutions of different chloride ion concentrations viz., 0.01 M, 0.1 M, 0.5 M and 1 M. The surface of the PEO coated specimens after 50 h of immersion/EIS testing was examined by optical microscopy and scanning electron microscopy. The results showed that the corrosion deterioration of PEO coated magnesium alloy in NaCl solutions was significantly influenced by chloride ion concentration. The silicate-based coating was found to offer a superior corrosion resistance to the magnesium substrate than the phosphate-based coatings in lower chloride ion concentration NaCl solutions (0.01 M and 0.1 M NaCl). On the other hand both these PEO coatings were found to be highly susceptible to localized damage, and could not provide an effective corrosion protection to Mg alloy substrate in solutions containing higher chloride concentrations (0.5 M and 1 M). The extent of localized damage was observed to be more with increase in chloride concentration in both the cases.

Ionic molar volumes in methanol mixtures with acetonitrile, N,N-dimethylformamide and propylene carbonate at T = 298.15 K

International Nuclear Information System (INIS)

Pietrzak, A.; Piekarski, H.

2014-01-01

Highlights: • Densities of electrolyte solutions in methanol mixtures were measured at T = 298.15 K. • Apparent molar volumes of sodium cation and iodide anion were determined. • TPTB as a calculation method was used. • Preferential solvation of ions by organic solvents was examined. - Abstract: The densities of dilute solutions of three electrolytes (NaI, NaBPh 4 and Ph 4 PI) in methanol mixtures with propylene carbonate (PC), N,N-dimethylformamide (DMF) and acetonitrile (AN) have been measured by Anton Paar 5000 densimeter at T = 298.15 K. Apparent molar volumes, V Φ have been determined at an electrolyte concentration of 0.06 mol · kg −1 over the entire mixed solvent composition range. Single ionic apparent molar volumes of transfer, Δ t V Φ (ion) were calculated using the tetraphenylphosphonium tetraphenylborate (TPTB) assumption. The results are discussed in terms of ionic preferential solvation

Solid electrolytes

Science.gov (United States)

Abraham, Kuzhikalail M.; Alamgir, Mohamed

1993-06-15

This invention pertains to Li ion (Li.sup.+) conductive solid polymer electrolytes composed of solvates of Li salts immobilized (encapsulated) in a solid organic polymer matrix. In particular, this invention relates to solid polymer electrolytes derived by immobilizing complexes (solvates) formed between a Li salt such as LiAsF.sub.6, LiCF.sub.3 SO.sub.3 or LiClO.sub.4 and a mixture of aprotic organic solvents having high dielectric constants such as ethylene carbonate (EC) (dielectric constant=89.6) and propylene carbonate (PC) (dielectric constant=64.4) in a polymer matrix such as polyacrylonitrile, poly(tetraethylene glycol diacrylate), or poly(vinyl pyrrolidinone).

Charge regulation at semiconductor-electrolyte interfaces.

Science.gov (United States)

Fleharty, Mark E; van Swol, Frank; Petsev, Dimiter N

2015-07-01

The interface between a semiconductor material and an electrolyte solution has interesting and complex electrostatic properties. Its behavior will depend on the density of mobile charge carriers that are present in both phases as well as on the surface chemistry at the interface through local charge regulation. The latter is driven by chemical equilibria involving the immobile surface groups and the potential determining ions in the electrolyte solution. All these lead to an electrostatic potential distribution that propagate such that the electrolyte and the semiconductor are dependent on each other. Hence, any variation in the charge density in one phase will lead to a response in the other. This has significant implications on the physical properties of single semiconductor-electrolyte interfaces and on the electrostatic interactions between semiconductor particles suspended in electrolyte solutions. The present paper expands on our previous publication (Fleharty et al., 2014) and offers new results on the electrostatics of single semiconductor interfaces as well as on the interaction of charged semiconductor colloids suspended in electrolyte solution. Copyright © 2014 Elsevier Inc. All rights reserved.

Miniaturized polymer electrolyte fuel cell (PEFC) stack using micro structured bipolar plate

Energy Technology Data Exchange (ETDEWEB)

Veziridis, Z; Scherer, G G; Marmy, Ch; Glaus, F [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1999-08-01

In Polymer Electrolyte Fuel Cell (PEFC) technology the reducing of volume and mass of the fuel cell stack and the improvement of catalyst utilization are of great interest. These parameters affect applicability and system cost. In this work we present an alternative way for reducing the stack volume by combining gas distribution and catalytic active area in one plate. Micro machined glassy carbon electrodes serve as support material for the platinum catalyst, as well as gas distributor at the same time. A comparison of these electrodes with conventional platinum-black gas diffusion electrodes under fuel cell conditions shows that the new system is a promising electrode type for enhanced power density and catalyst utilization. (author) 3 figs., 5 refs.

Scan-Mode Atmospheric-Pressure Plasma Jet Processed Reduced Graphene Oxides for Quasi-Solid-State Gel-Electrolyte Supercapacitors

Directory of Open Access Journals (Sweden)

Aliyah R. Hsu

2018-01-01

Full Text Available A scanning atmospheric-pressure plasma jet (APPJ is essential for high-throughput large-area and roll-to-roll processes. In this study, we evaluate scan-mode APPJ for processing reduced graphene oxides (rGOs that are used as the electrodes of quasi-solid-state gel-electrolyte supercapacitors. rGO nanoflakes are mixed with ethyl cellulose (EC and terpineol to form pastes for screen-printing. After screen-printing the pastes on carbon cloth, a DC-pulse nitrogen APPJ is used to process the pastes in the scan mode. The maximal temperature attained is ~550 °C with a thermal influence duration of ~10 s per scan. The pastes are scanned by APPJ for 0, 1, 3 and 5 times. X-ray photoelectron spectroscopy (XPS indicates the reduction of C-O binding content as the number of scan increases, suggesting the oxidation/decomposition of EC. The areal capacitance increases and then decreases as the number of scan increases; the best achieved areal capacitance is 15.93 mF/cm2 with one APPJ scan, in comparison to 4.38 mF/cm2 without APPJ processing. The capacitance retention rate of the supercapacitor with the best performance is ~93% after a 1000-cycle cyclic voltammetry (CV test. The optimal number of APPJ scans should enable the proper removal of inactive EC and improved wettability while minimizing the damage caused to rGOs by nitrogen APPJ processing.

An Alternative to Annealing TiO2 Nanotubes for Morphology Preservation: Atmospheric Pressure Plasma Jet Treatment.

Science.gov (United States)

Seo, Sang-Hee; Uhm, Soo-Hyuk; Kwon, Jae-Sung; Choi, Eun Ha; Kim, Kwang-Mahn; Kim, Kyoung-Nam

2015-03-01

Titanium oxide nanotube layer formed by plasma electrolytic oxidation (PEO) is known to be excellent in biomaterial applications. However, the annealing process which is commonly performed on the TiO2 nanotubes cause defects in the nanotubular structure. The purpose of this work was to apply a non-thermal atmospheric pressure plasma jet on diameter-controlled TiO2 nanotubes to mimic the effects of annealing while maintaining the tubular structure for use as biomaterial. Diameter-controlled nanotube samples fabricated by plasma electrolytic oxidation were dried and prepared under three different conditions: untreated, annealed at 450 °C for 1 h in air with a heating rate of 10 °C/min, and treated with an air-based non-thermal atmospheric pressure plasma jet for 5 minutes. The contact angle measurement was investigated to confirm the enhanced hydrophilicity of the TiO2 nanotubes. The chemical composition of the surface was studied using X-ray photoelectron spectroscopy, and the morphology of TiO2 nanotubes was examined by field emission scanning electron microscopy. For the viability of the cell, the attachment of the osteoblastic cell line MC3T3-E1 was determined using the water-soluble tetrazolium salt assay. We found that there are no morphological changes in the TiO2 nanotubular structure after the plasma treatment. Also, we investigated a change in the chemical composition and enhanced hydrophilicity which result in improved cell behavior. The results of this study indicated that the non-thermal atmospheric pressure plasma jet results in osteoblast functionality that is comparable to annealed samples while maintaining the tubular structure of the TiO2 nanotubes. Therefore, this study concluded that the use of a non-thermal atmospheric pressure plasma jet on nanotube surfaces may replace the annealing process following plasma electrolytic oxidation.

A 5 kA pulsed power supply for inductive and plasma loads in large volume plasma device

Energy Technology Data Exchange (ETDEWEB)

Srivastava, P. K., E-mail: pkumar@ipr.res.in; Singh, S. K.; Sanyasi, A. K.; Awasthi, L. M., E-mail: kushagra.lalit@gmail.com; Mattoo, S. K. [Institute for Plasma Research, Gandhinagar (India)

2016-07-15

This paper describes 5 kA, 12 ms pulsed power supply for inductive load of Electron Energy Filter (EEF) in large volume plasma device. The power supply is based upon the principle of rapid sourcing of energy from the capacitor bank (2.8 F/200 V) by using a static switch, comprising of ten Insulated Gate Bipolar Transistors (IGBTs). A suitable mechanism is developed to ensure equal sharing of current and uniform power distribution during the operation of these IGBTs. Safe commutation of power to the EEF is ensured by the proper optimization of its components and by the introduction of over voltage protection (>6 kV) using an indigenously designed snubber circuit. Various time sequences relevant to different actions of power supply, viz., pulse width control and repetition rate, are realized through optically isolated computer controlled interface.

The installation and dismantling of electrolytic cells

International Nuclear Information System (INIS)

Galushkin, N.V.

1995-01-01

This chapter of monograph is devoted to construction of aluminium electrolytic cells, their installation and dismantling. Therefore, the general characteristic and classification of aluminium electrolytic cells was considered. The anode and cathode structure was studied. The lining of cathode casing, the process of collection of anode gases, electrolytic cell cover, and electrical insulation was studied as well. The installation and dismantling of aluminium electrolytic cells was described.

Underscreening in concentrated electrolytes.

Science.gov (United States)

Lee, Alpha A; Perez-Martinez, Carla S; Smith, Alexander M; Perkin, Susan

2017-07-01

Screening of a surface charge by an electrolyte and the resulting interaction energy between charged objects is of fundamental importance in scenarios from bio-molecular interactions to energy storage. The conventional wisdom is that the interaction energy decays exponentially with object separation and the decay length is a decreasing function of ion concentration; the interaction is thus negligible in a concentrated electrolyte. Contrary to this conventional wisdom, we have shown by surface force measurements that the decay length is an increasing function of ion concentration and Bjerrum length for concentrated electrolytes. In this paper we report surface force measurements to test directly the scaling of the screening length with Bjerrum length. Furthermore, we identify a relationship between the concentration dependence of this screening length and empirical measurements of activity coefficient and differential capacitance. The dependence of the screening length on the ion concentration and the Bjerrum length can be explained by a simple scaling conjecture based on the physical intuition that solvent molecules, rather than ions, are charge carriers in a concentrated electrolyte.

Heavy-water extraction from non-electrolytic hydrogen streams

International Nuclear Information System (INIS)

LeRoy, R.L.; Hammerli, M.; Butler, J.P.

1981-01-01

Heavy water may be produced from non-electrolytic hydrogen streams using a combined electrolysis and catalytic exchange process. The method comprises contacting feed water in a catalyst column with hydrogen gas originating partly from a non-electrolytic hydrogen stream and partly from an electrolytic hydrogen stream, so as to enrich the feed water with the deuterium extracted from both the non-electrolytic and electrolytic hydrogen gas, and passing the deuterium water to an electrolyser wherein the electrolytic hydrogen gas is generated and then fed through the catalyst column. (L.L.)

Development of Sulfide Solid Electrolytes and Interface Formation Processes for Bulk-Type All-Solid-State Li and Na Batteries

Energy Technology Data Exchange (ETDEWEB)

Hayashi, Akitoshi, E-mail: hayashi@chem.osakafu-u.ac.jp [Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, Sakai, Osaka (Japan); Sakuda, Atsushi [Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, Sakai, Osaka (Japan); Department of Energy and Environment, Research Institute of Electrochemical Energy, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka (Japan); Tatsumisago, Masahiro [Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, Sakai, Osaka (Japan)

2016-07-15

All-solid-state batteries with inorganic solid electrolytes (SEs) are recognized as an ultimate goal of rechargeable batteries because of their high safety, versatile geometry, and good cycle life. Compared with thin-film batteries, increasing the reversible capacity of bulk-type all-solid-state batteries using electrode active material particles is difficult because contact areas at solid–solid interfaces between the electrode and electrolyte particles are limited. Sulfide SEs have several advantages of high conductivity, wide electrochemical window, and appropriate mechanical properties, such as formability, processability, and elastic modulus. Sulfide electrolyte with Li{sub 7}P{sub 3}S{sub 11} crystal has a high Li{sup +} ion conductivity of 1.7 × 10{sup −2} S cm{sup −1} at 25°C. It is far beyond the Li{sup +} ion conductivity of conventional organic liquid electrolytes. The Na{sup +} ion conductivity of 7.4 × 10{sup −4} S cm{sup −1} is achieved for Na{sub 3.06}P{sub 0.94}Si{sub 0.06}S{sub 4} with cubic structure. Moreover, formation of favorable solid–solid interfaces between electrode and electrolyte is important for realizing solid-state batteries. Sulfide electrolytes have better formability than oxide electrolytes. Consequently, a dense electrolyte separator and closely attached interfaces with active material particles are achieved via “room-temperature sintering” of sulfides merely by cold pressing without heat treatment. Elastic moduli for sulfide electrolytes are smaller than that of oxide electrolytes, and Na{sub 2}S–P{sub 2}S{sub 5} glass electrolytes have smaller Young’s modulus than Li{sub 2}S–P{sub 2}S{sub 5} electrolytes. Cross-sectional SEM observations for a positive electrode layer reveal that sulfide electrolyte coating on active material particles increases interface areas even with a minimum volume of electrolyte, indicating that the energy density of bulk-type solid-state batteries is enhanced. Both surface coating

Nuclear electrolytic hydrogen

International Nuclear Information System (INIS)

Barnstaple, A.G.; Petrella, A.J.

1982-05-01

An extensive study of hydrogen supply has recently been carried out by Ontario Hydro which indicates that electrolytic hydrogen produced from nuclear electricity could offer the lowest cost option for any future large scale hydrogen supply in the Province of Ontario, Canada. This paper provides a synopsis of the Ontario Hydro study, a brief overview of the economic factors supporting the study conclusion and discussion of a number of issues concerning the supply of electrolytic hydrogen by electric power utilities

Electrolytic preconcentration in instrumental analysis.

Science.gov (United States)

Sioda, R E; Batley, G E; Lund, W; Wang, J; Leach, S C

1986-05-01

The use of electrolytic deposition as a separation and preconcentration step in trace metal analysis is reviewed. Both the principles and applications of the technique are dealt with in some detail. Electrolytic preconcentration can be combined with a variety of instrumental techniques. Special attention is given to stripping voltammetry, potentiometric stripping analysis, different combinations with atomic-absorption spectrometry, and the use of flow-through porous electrodes. It is pointed out that the electrolytic preconcentration technique deserves more extensive use as well as fundamental investigation.

The Influence of the Electrolyte Nature and PEO Process Parameters on Properties of Anodized Ti-15Mo Alloy Intended for Biomedical Applications

Directory of Open Access Journals (Sweden)

Oksana Banakh

2018-05-01

Full Text Available Plasma electrolytic oxidation (PEO of Ti-15Mo alloys conducted in electrolytes containing Ca and P compounds can be an efficient process with which to obtain bioactive coatings. This paper reports on the influence of the nature of the electrolyte, its concentration, and PEO process parameters on the properties of anodized layers on Ti-15Mo. A wide range of Ca- and P-containing alkaline and acidic solutions was employed to incorporate Ca and P ions into the anodized layer. The efficiency of the incorporation was evaluated by the Ca/P ratio in the coating as compared to that in the electrolyte. It was found that alkaline solutions are not suitable electrolytes for the formation of good quality, uniform PEO coatings. Only acidic electrolytes are appropriate for obtaining well-adherent homogeneous layers on Ti-15Mo. However, the maximum Ca/P ratios reached in the coatings were rather low (close to 1. The variation of electrical signal (negative-to-positive current ratio, frequency and time of electrolysis do not result in a substantial change of this value. The processing time, however, did influence the coating thickness. Despite their low Ca/P ratio, the anodized layers demonstrate good biological activity, comparable to pure microrough titanium.

Pulmonary Edema and Plasma Volume Changes in Dysbarism. M.S. Thesis - Texas Univ.

Science.gov (United States)

Joki, J. A.

1972-01-01

Two groups of anesthetized, fasted pigs were utilized. One group of 13 animals (8.5 to 16.6 kilograms) was exposed to a high-pressure environment, and the other group of eight animals (6.9 to 20.0 kilograms) constituted the control group. The experimental group was subjected to an atmosphere of 90 percent nitrogen and 10 percent oxygen at a pressure of 50 psig for 30 minutes and then decompressed at a rate 10 psi/min. Plasma volumes, using both iodine-125-tagged-albumin and chromium-51-tagged-cell dilution techniques, were measured before, immediately after, and at 30 and 60 minutes after decompression. Aortic and right-ventricular systolic pressures were also recorded. At 60 minutes after decompression, blood samples were taken, the animals were sacrificed, and the water content of the lungs, kidneys, livers, and spleens was estimated by measuring tissue wet weight and dry weight. Protein extravasation and tissue blood volumes were determined by measuring the iodine-125-tagged-albumin and chromium-51-tagged-cell spaces in homo-genates of the organs under investigation.

Thermodynamics of electrolytes. III. Activity and osmotic coefficients for 2-2 electrolytes

Energy Technology Data Exchange (ETDEWEB)

Pitzer, K.S.; Mayorga, G.

1974-01-01

The peculiar behavior of 2-2 and higher valence type electrolytes is discussed in terms of various theories some of which assume, while others do not, an equilibrium between separated ions and ion pairs as distinct chemical species. It is recognized that in some cases a distinct species of inner-shell ion pairs is indicated by spectroscopic or ultrasonic data. Nevertheless, there are many advantages in representing, if possible, the properties of these electrolytes by appropriate virial coefficients and without chemical association equilibria. It is shown that this is possible and is conveniently accomplished by the addition of these equations are given for nine solutes. It is also noted that these equations have been successfully applied to mixed electrolytes involving one component of the 2-2 type. 2 figures, 1 table.

Intravenous hypertonic saline solution (7.5%) and oral electrolytes to treat of calves with noninfectious diarrhea and metabolic acidosis.

Science.gov (United States)

Leal, M L R; Fialho, S S; Cyrillo, F C; Bertagnon, H G; Ortolani, E L; Benesi, F J

2012-01-01

The aim of this study was to compare the efficacy of treating osmotic diarrhea and dehydration in calves with hypertonic saline solution (HSS) IV, isotonic electrolyte solution (IES) PO, and a combination of these 2 solutions (HSS + IES). Eighteen male calves 8-30 days of age were used to evaluate the efficacy of 3 methods of fluid therapy after induction of osmotic diarrhea and dehydration. The diarrhea and dehydration were induced by administration of saccharose, spironolactone, and hydrochlorothiazide for 48 hours. The animals were randomly divided into 3 experimental groups: Group 1: 7.2% hypertonic saline solution-HSS (5 mL/kg IV); Group 2: oral isotonic electrolyte solution IES (60 mL/kg PO); or Group 3: HSS+IES. Clinical signs and laboratory finding observed 48 hours post-induction (Time 0) included diarrhea, dehydration, lethargy, and metabolic acidosis. Calves treated with HSS + IES experienced decreases in hematocrit, total protein concentration, albumin concentration, urea nitrogen concentration, and plasma volume as well as increases in blood pH, blood bicarbonate concentration, and central venous pressure between 1 and 3 hours post-treatment. These findings also were observed in animals treated with IES, however, at a slower rate than in the HSS + IES-treated animals. Animals treated with HSS continued to display signs of dehydration, lethargy, and metabolic acidosis 24 hours post-treatment. Treatment with a combination of HSS and IES produced rapid and sustainable correction of hypovolemia and metabolic acidosis in calves with noninfections diarrhea and dehydration. Copyright © 2012 by the American College of Veterinary Internal Medicine.

Nonflammable perfluoropolyether-based electrolytes for lithium batteries

Science.gov (United States)

Wong, Dominica H. C.; Thelen, Jacob L.; Fu, Yanbao; Devaux, Didier; Pandya, Ashish A.; Battaglia, Vincent S.; Balsara, Nitash P.; DeSimone, Joseph M.

2014-01-01

The flammability of conventional alkyl carbonate electrolytes hinders the integration of large-scale lithium-ion batteries in transportation and grid storage applications. In this study, we have prepared a unique nonflammable electrolyte composed of low molecular weight perfluoropolyethers and bis(trifluoromethane)sulfonimide lithium salt. These electrolytes exhibit thermal stability beyond 200 °C and a remarkably high transference number of at least 0.91 (more than double that of conventional electrolytes). Li/LiNi1/3Co1/3Mn1/3O2 cells made with this electrolyte show good performance in galvanostatic cycling, confirming their potential as rechargeable lithium batteries with enhanced safety and longevity. PMID:24516123

The Solubility of Aluminum in Cryolite-Based Electrolyte-Containing KF

Science.gov (United States)

Zhang, Yu; Yu, Jiangyu; Gao, Bingliang; Liu, Yibai; Hu, Xianwei; Shi, Zhongning; Wang, Zhaowen

2016-04-01

The solubility of aluminum in NaF-AlF3-CaF2-KF-A12O3 electrolyte system at 1253 K (980 °C) has been measured by the analysis of quenched samples saturated with aluminum. The content of the dissolved metal in the quenched melt was determined by collecting the volume of hydrogen gas when a finely crushed sample is treated with HCl. Addition of 0 to 5 pct KF has no obvious effect on the solubility of aluminum in cryolite-based melts with molar ratio of NaF/AlF3 (cryolite ratio) ranging from 2.2 to 3.0. The solubility of aluminum increases from 0.015 to 0.026 wt pct with cryolite ratio increases from 2.2 to 4.0 in the NaF-AlF3-5 wt pct CaF2-3 wt pct A12O3 electrolyte at 1253 K (980 °C). Aluminum solubility was affected by both chemical replacement reaction of Al + 3NaF = AlF3 + 3Na and physical dissolution.

Structural, photoluminescent and photocatalytic properties of TiO{sub 2}:Eu{sup 3+} coatings formed by plasma electrolytic oxidation

Energy Technology Data Exchange (ETDEWEB)

Stojadinović, Stevan, E-mail: sstevan@ff.bg.ac.rs [University of Belgrade, Faculty of Physics, Studentski trg 12–16, Belgrade 11000 (Serbia); Radić, Nenad; Grbić, Boško [University of Belgrade, Institute of Chemistry, Technology and Metallurgy, Department of Catalysis and Chemical Engineering, Njegoševa 12, Belgrade 11000 (Serbia); Maletić, Slavica [University of Belgrade, Faculty of Physics, Studentski trg 12–16, Belgrade 11000 (Serbia); Stefanov, Plamen [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Block 11, Sofia 1113 (Bulgaria); Pačevski, Aleksandar [University of Belgrade, Faculty of Mining and Geology, Đušina 7, 11000 Belgrade (Serbia); Vasilić, Rastko [University of Belgrade, Faculty of Physics, Studentski trg 12–16, Belgrade 11000 (Serbia)

2016-05-01

Graphical abstract: - Highlights: • TiO{sub 2}:Eu{sup 3+} coatings are formed by plasma electrolytic oxidation (PEO). • Photoluminescence is related to transitions of Eu{sup 3+} from level {sup 5}D{sub 0} to levels {sup 7}F{sub J}. • Eu{sup 3+} ions occupy non-inversion symmetry sites in the coatings. • PEO time is an important factor affecting photocatalytic activity. - Abstract: In this paper, we used plasma electrolytic oxidation (PEO) of titanium in water solution containing 10 g/L Na{sub 3}PO{sub 4}·12H{sub 2}O + 2 g/L Eu{sub 2}O{sub 3} powder for preparation of TiO{sub 2}:Eu{sup 3+} coatings. The surfaces of obtained coatings exhibit a typical PEO porous structure. The energy dispersive X-ray spectroscopy analysis showed that the coatings are mainly composed of Ti, O, P, and Eu; it is observed that Eu content in the coatings increases with PEO time. The X-ray diffraction analysis indicated that the coatings are crystallized and composed of anatase and rutile TiO{sub 2} phases, with anatase being the dominant one. X-ray photoelectron spectroscopy revealed that Ti 2p spin-orbit components of TiO{sub 2}:Eu{sup 3+} coatings are shifted towards higher binding energy, with respect to pure TiO{sub 2} coatings, suggesting that Eu{sup 3+} ions are incorporated into TiO{sub 2} lattice. Diffuse reflectance spectroscopy showed that TiO{sub 2}:Eu{sup 3+} coatings exhibit evident red shift with respect to the pure TiO{sub 2} coatings. Photoluminescence (PL) emission spectra of TiO{sub 2}:Eu{sup 3+} coatings are characterized by sharp emission bands in orange–red region ascribed to f–f transitions of Eu{sup 3+} ions from excited level {sup 5}D{sub 0} to lower levels {sup 7}F{sub J} (J = 0, 1, 2, 3, and 4). The excitation PL spectra of TiO{sub 2}:Eu{sup 3+} coatings can be divided into two regions: the broad band region from 250 nm to 350 nm associated with charge transfer state of Eu{sup 3+} and the series of sharp peaks in the range from 350 nm to 550 nm

Lithium-ion transport in inorganic solid state electrolyte

International Nuclear Information System (INIS)

Gao Jian; Li Hong; Zhao Yu-Sheng; Shi Si-Qi

2016-01-01

An overview of ion transport in lithium-ion inorganic solid state electrolytes is presented, aimed at exploring and designing better electrolyte materials. Ionic conductivity is one of the most important indices of the performance of inorganic solid state electrolytes. The general definition of solid state electrolytes is presented in terms of their role in a working cell (to convey ions while isolate electrons), and the history of solid electrolyte development is briefly summarized. Ways of using the available theoretical models and experimental methods to characterize lithium-ion transport in solid state electrolytes are systematically introduced. Then the various factors that affect ionic conductivity are itemized, including mainly structural disorder, composite materials and interface effects between a solid electrolyte and an electrode. Finally, strategies for future material systems, for synthesis and characterization methods, and for theory and calculation are proposed, aiming to help accelerate the design and development of new solid electrolytes. (topical review)

Solid electrolyte fuel cells

Science.gov (United States)

Isaacs, H. S.

Progress in the development of functioning solid electrolyte fuel cells is summarized. The solid electrolyte cells perform at 1000 C, a temperature elevated enough to indicate high efficiencies are available, especially if the cell is combined with a steam generator/turbine system. The system is noted to be sulfur tolerant, so coal containing significant amounts of sulfur is expected to yield satisfactory performances with low parasitic losses for gasification and purification. Solid oxide systems are electrically reversible, and are usable in both fuel cell and electrolysis modes. Employing zirconium and yttrium in the electrolyte provides component stability with time, a feature not present with other fuel cells. The chemical reactions producing the cell current are reviewed, along with materials choices for the cathodes, anodes, and interconnections.

Reduction of waste solution volume generated on electrokinetic remediation

Energy Technology Data Exchange (ETDEWEB)

Kim, Gye-Nam; Koo, Dae-Seo; Kim, Seung-Soo; Jeong, Jung-Whan; Han, Gyu-Seong; Moon, Jei-Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-05-15

In this study, for the reduction of volume of metal oxides generated in cathode chamber, the optimum pH of waste electrolyte in cathode chamber were drawn out through several experiments with the manufactured electrokinetic decontamination equipment. Also, the required time to reach to below the clearance concentration level for self- disposal was estimated through experiments using the manufactured electrokinetic decontamination equipment. A diagram of soil decontamination process for the removal of uranium from contaminated soil was drawn out. The optimum pH of waste electrolyte in cathode chamber for the reduction of volume of metal oxides was below 2.35. Also, when the initial uranium concentration of the soils were 7-20 Bq/g, the required times to reach to below the clearance concentration level for self- disposal were 25-40 days. A diagram of soil decontamination process for the removal of uranium from contaminated soil was drawn out.

Atmospheric pressure plasma processing of polymeric materials utilizing close proximity indirect exposure

Science.gov (United States)

Paulauskas, Felix L.; Bonds, Truman

2016-09-20

A plasma treatment method that includes providing treatment chamber including an intermediate heating volume and an interior treatment volume. The interior treatment volume contains an electrode assembly for generating a plasma and the intermediate heating volume heats the interior treatment volume. A work piece is traversed through the treatment chamber. A process gas is introduced to the interior treatment volume of the treatment chamber. A plasma is formed with the electrode assembly from the process gas, wherein a reactive species of the plasma is accelerated towards the fiber tow by flow vortices produced in the interior treatment volume by the electrode assembly.

Physics of failure based analysis of aluminium electrolytic capacitor

International Nuclear Information System (INIS)

Sahoo, Satya Ranjan; Behera, S.K.; Kumar, Sachin; Varde, P.V.; Ravi Kumar, G.

2016-01-01

Electrolytic capacitors are one of the important devices in various power electronic systems, such as motor drives, uninterruptible power supply, electric vehicles and dc power supply. Electrolytic capacitors are also the integral part of many other electronic devices. One of the primary function of electrolytic capacitors is the smoothing of voltage ripple and storing electrical energy. However, the electrolytic capacitor has the shortest lifespan of components in power electronics. Past experiences show that electrolytic capacitor tends to degrade and fail faster under high electrical or thermal stress conditions during operations. The primary failure mechanism of an electrolytic capacitor is the evaporation of the electrolyte due to electrical or thermal overstress. This leads to the drift in the values of two important parameters-capacitance and equivalent series resistance (ESR) of the electrolytic capacitor. An attempt has been made to age the electrolytic capacitor and validate the results. The overall goal is to derive the accurate degradation model of the electrolytic capacitor. (author)

Characterization of the island divertor plasma of W7-AS stellarator in the deeply detached state with volume recombination

International Nuclear Information System (INIS)

Ramasubramanian, N.; Koenig, R.; Feng, Y.; Giannone, L.; Grigull, P.; Klinger, T.; McCormick, K.; Thomsen, H.; Wenzel, U.

2004-01-01

In the high-density H-mode of the Stellarator Wendelstein 7-AS, the plasma detaches from the island divertor targets when the line-averaged density exceeds a critical value. This quasi-stationary detachment is found to be partial and shows edge-localized, poloidally asymmetric radiation. The spectroscopic characteristics of the deeply detached plasma are reported, including evidence for volume recombination. The detached plasma radiates up to 90% of the absorbed power with larger contributions from the locations close to magnetic X-points outside the divertor region. The spectral analysis of the Balmer series indicate very high densities and low temperatures at the detached regions. The results of the spectral analysis underline the importance of three-dimensional modelling. An initial comparison is made with the latest results from EMC3-EIRENE modelling. (author)

A Revival of Waste: Atmospheric Pressure Nitrogen Plasma Jet Enhanced Jumbo Silicon/Silicon Carbide Composite in Lithium Ion Batteries.

Science.gov (United States)

Chen, Bing-Hong; Chuang, Shang-I; Liu, Wei-Ren; Duh, Jenq-Gong

2015-12-30

In this study, a jumbo silicon/silicon carbide (Si/SiC) composite (JSC), a novel anode material source, was extracted from solar power industry cutting waste and used as a material for lithium-ion batteries (LIBs), instead of manufacturing the nanolized-Si. Unlike previous methods used for preventing volume expansion and solid electrolyte interphase (SEI), the approach proposed here simply entails applying surface modification to JSC-based electrodes by using nitrogen-atmospheric pressure plasma jet (N-APPJ) treatment process. Surface organic bonds were rearranged and N-doped compounds were formed on the electrodes through applying different plasma treatment durations, and the qualitative examinations of before/after plasma treatment were identified by X-ray photoelectron spectroscopy (XPS) and electron probe microanalyzer (EPMA). The surface modification resulted in the enhancement of electrochemical performance with stable capacity retention and high Coulombic efficiency. In addition, depth profile and scanning electron microscope (SEM) images were executed to determine the existence of Li-N matrix and how the nitrogen compounds change the surface conditions of the electrodes. The N-APPJ-induced rapid surface modification is a major breakthrough for processing recycled waste that can serve as anode materials for next-generation high-performance LIBs.

Electrolytic installation in order to obtain deuterium and to fill the pressure deposits; Instalacion electrolitica para la obtencion de deuterio y llenado de depositos a preseion

Energy Technology Data Exchange (ETDEWEB)

Cordero Lopez, F; Tanarro Sanz, A

1959-07-01

In order to obtain deuterium to feed the ion sources of the accelerators an easy and automatic electrolytic installation has been prepared. this installation and a small compressor designed and constructed for this purpose permit to fill deposits of 1 or 2 liters capacity with deuterium, till a 4 atmosphere pressure in few hours of operation. The electrolytic cell has V shape and permits operation with 3 cc heavy water only as it has small dead volume; the electrodes are platinum and as electrolyte an OH Na solution in a proportion of 15 w/o is used. (Author) 3 refs.

Modelling of an intermediate pressure microwave oxygen discharge reactor: from stationary two-dimensional to time-dependent global (volume-averaged) plasma models

International Nuclear Information System (INIS)

Kemaneci, Efe; Graef, Wouter; Rahimi, Sara; Van Dijk, Jan; Kroesen, Gerrit; Carbone, Emile; Jimenez-Diaz, Manuel

2015-01-01

A microwave-induced oxygen plasma is simulated using both stationary and time-resolved modelling strategies. The stationary model is spatially resolved and it is self-consistently coupled to the microwaves (Jimenez-Diaz et al 2012 J. Phys. D: Appl. Phys. 45 335204), whereas the time-resolved description is based on a global (volume-averaged) model (Kemaneci et al 2014 Plasma Sources Sci. Technol. 23 045002). We observe agreement of the global model data with several published measurements of microwave-induced oxygen plasmas in both continuous and modulated power inputs. Properties of the microwave plasma reactor are investigated and corresponding simulation data based on two distinct models shows agreement on the common parameters. The role of the square wave modulated power input is also investigated within the time-resolved description. (paper)

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African Journals Online (AJOL)

Dr Olaleye

Body fluid and electrolyte balance are essential for normal cellular function, maintenance of adequate plasma volume and ... Group A - given the vegetable oil (vehicle) to serve as .... contraceptives: renin aldostrone and high blood pressure.

Low density lipoprotein for oxidation and metabolic studies. Isolation from small volumes of plasma using a tabletop ultracentrifuge.

Science.gov (United States)

Himber, J; Bühler, E; Moll, D; Moser, U K

1995-01-01

A rapid method is described for the isolation of small volumes of plasma low density lipoprotein (LDL) free of plasma protein contaminants using the TL-100 Tabletop Ultracentrifuge (Beckman). The isolation of LDL was achieved by a 25 min discontinuous gradient density centrifugation between the density range of 1.006 and 1.21 g/ml, recovery of LDL by tube slicing followed by a 90 min flotation step (d = 1.12 g/ml). The purity of LDL and apolipoprotein B100 (apo B100) were monitored by agarose electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), radial immunodiffusion and micropreparative fast protein liquid chromatography (FPLC). The ability of LDL oxidation was assessed by following absorbance at 234 nm after addition of copper ions. The functional integrity of the isolated LDL was checked by clearance kinetics after injection of [125I]-labelled LDL in estrogen-treated rats. The additional purification step led to LDL fractions free of protein contamination and left apo B100, alpha-tocopherol and beta-carotene intact. The LDL prepared in this way was free of albumin, as evident from analytic tests and from its enhanced oxidative modification by copper ions. Used for analytical purposes, this method allows LDL preparations from plasma volumes up to 570 microliters. This method is also convenient for metabolic studies in small animals, especially those relating to the determination of kinetic parameters of LDL in which LDL-apo B100 has to be specifically radiolabelled.

The potential role of electrolytic hydrogen in Canada

International Nuclear Information System (INIS)

Hammerli, M.

1982-03-01

The potential role of electrolytic hydrogen in Canada is assessed for the period 1980 to 2025 for large-scale uses only. Present uses of hydrogen, and specifically electrolytic hydrogen, are discussed briefly and hydrogen production processes are summarized. Only hydrogen derived from natural gas, coal, or electrolysis of sater are considered. Cost estimates of electrolytic hydrogen are obtained from a parametric equation, comparing values for unipolar water elecctrklyser technologies with those for bipolar electrolysers. Both by-products of electrolytic hydrogen production, namely heavy water and oxygen, are evaluated. Electrolytic hydrogen, based on non-fossil primary energy sources, is also considered as ankther 'liquid fuel option' for Canada along with the alcohols. The market potential for hydrogen in general and electrolytic hydrogen is assessed. Results show that the market potential for electrolytic hydrogen is large by the year 2025

Li-Ion Cells Employing Electrolytes With Methyl Propionate and Ethyl Butyrate Co-Solvents

Science.gov (United States)

Smart, Marshall C.; Bugga, Ratnakumar V.

2011-01-01

Future NASA missions aimed at exploring Mars and the outer planets require rechargeable batteries that can operate at low temperatures to satisfy the requirements of such applications as landers, rovers, and penetrators. A number of terrestrial applications, such as hybrid electric vehicles (HEVs) and electric vehicles (EVs) also require energy storage devices that can operate over a wide temperature range (i.e., -40 to +70 C), while still providing high power capability and long life. Currently, the state-of-the-art lithium-ion system has been demonstrated to operate over a wide range of temperatures (-30 to +40 C); however, the rate capability at the lower temperatures is very poor. These limitations at very low temperatures are due to poor electrolyte conductivity, poor lithium intercalation kinetics over the electrode surface layers, and poor ionic diffusion in the electrode bulk. Two wide-operating-temperature-range electrolytes have been developed based on advances involving lithium hexafluorophosphate-based solutions in carbonate and carbonate + ester solvent blends, which have been further optimized in the context of the technology and targeted applications. The approaches employed include further optimization of electrolytes containing methyl propionate (MP) and ethyl butyrate (EB), which are effective co-solvents, to widen the operating temperature range beyond the baseline systems. Attention was focused on further optimizing ester-based electrolyte formulations that have exhibited the best performance at temperatures ranging from -60 to +60 C, with an emphasis upon improving the rate capability at -20 to -40 C. This was accomplished by increasing electrolyte salt concentration to 1.20M and increasing the ester content to 60 percent by volume to increase the ionic conductivity at low temperatures. Two JPL-developed electrolytes 1.20M LiPF6 in EC+EMC+MP (20:20:60 v/v %) and 1.20M LiPF6 in EC+EMC+EB (20:20:60 v/v %) operate effectively over a wide

In situ fabrication of blue ceramic coatings on wrought Al Alloy 2024 by plasma electrolytic oxidation

International Nuclear Information System (INIS)

Wang Zhijiang; Nie Xueyuan; Hu, Henry; Hussein, Riyad O.

2012-01-01

In situ formation of ceramic coatings on 2024 Al alloy with a blue color was successfully achieved using a plasma electrolytic oxidation process working at atmospheric pressure. This novel blue ceramic coating overcomes the shortcomings of surface treatments resulting from conventional dyeing processes by depositing organic dyes into the porous structure of anodic film, which has poor resistance to abrasion and rapid fading when exposed to sunlight. X-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy were employed to characterize the microstructure of the blue ceramic coating. The fabricated ceramic coating was composed of CoAl 2 O 4 , α-Al 2 O 3 , and γ-Al 2 O 3. By controlling the working parameters, the distribution of the CoAl 2 O 4 phase on the surface can be adjusted, and plays a key role in the appearance of the coating. Electrochemical testing, thermal cycling method, and pin-on-disk sliding wear testing were employed to evaluate corrosion, thermal cycling, and wear resistance of the ceramic coatings. The results indicate that the blue ceramic coating has a similar polarization resistance to that of conventional anodic film and can significantly enhance the corrosion resistance of aluminum alloy. There are no destructive horizontal cracks observed within the blue ceramic coating when subjected to 120 times of thermal cycling, which heats the samples up to 573 K and followed by submersion in water at room temperature for 10 min. Compared with the aluminum substrate as well as a conventional anodic film coated aluminum sample, the wear resistance of the blue ceramic coating coated sample was significantly increased while the coefficient of friction was decreased from 0.34 to 0.14.

Review of progresses on clinical applications of ion selective electrodes for electrolytic ion tests: from conventional ISEs to graphene-based ISEs

Directory of Open Access Journals (Sweden)

Rongguo Yan

2016-10-01

Full Text Available There exist several positively and negatively charged electrolytes or ions in human blood, urine, and other body fluids. Tests that measure the concentration of these ions in clinics are performed using a more affordable, portable, and disposable potentiometric sensing method with few sample volumes, which requires the use of ion-selective electrodes (ISEs and reference electrodes. This review summarily descriptively presents progressive developments and applications of ion selective electrodes in medical laboratory electrolytic ion tests, from conventional ISEs, solid-contact ISEs, carbon nanotube based ISEs, to graphene-based ISEs.

Fibrinogen Reduction During Selective Plasma Exchange due to Membrane Fouling.

Science.gov (United States)

Ohkubo, Atsushi; Okado, Tomokazu; Miyamoto, Satoko; Hashimoto, Yurie; Komori, Shigeto; Yamamoto, Motoki; Maeda, Takuma; Itagaki, Ayako; Yamamoto, Hiroko; Seshima, Hiroshi; Kurashima, Naoki; Iimori, Soichiro; Naito, Shotaro; Sohara, Eisei; Uchida, Shinichi; Rai, Tatemitsu

2017-06-01

Fibrinogen is substantially reduced by most plasmapheresis modalities but retained in selective plasma exchange using Evacure EC-4A10 (EC-4A). Although EC-4A's fibrinogen sieving coefficient is 0, a session of selective plasma exchange reduced fibrinogen by approximately 19%. Here, we investigated sieving coefficient in five patients. When the mean processed plasma volume was 1.15 × plasma volume, the mean reduction of fibrinogen during selective plasma exchange was approximately 15%. Fibrinogen sieving coefficient was 0 when the processed plasma volume was 1.0 L, increasing to 0.07 when the processed plasma volume was 3.0 L, with a mean of 0.03 during selective plasma exchange. When fibrinogen sieving coefficient was 0, selective plasma exchange reduced fibrinogen by approximately 10%. Scanning electron microscopy images revealed internal fouling of EC-4A's hollow fiber membrane by substances such as fibrinogen fibrils. Thus, fibrinogen reduction by selective plasma exchange may be predominantly caused by membrane fouling rather than filtration. © 2017 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.

3D-Printing Electrolytes for Solid-State Batteries.

Science.gov (United States)

McOwen, Dennis W; Xu, Shaomao; Gong, Yunhui; Wen, Yang; Godbey, Griffin L; Gritton, Jack E; Hamann, Tanner R; Dai, Jiaqi; Hitz, Gregory T; Hu, Liangbing; Wachsman, Eric D

2018-05-01

Solid-state batteries have many enticing advantages in terms of safety and stability, but the solid electrolytes upon which these batteries are based typically lead to high cell resistance. Both components of the resistance (interfacial, due to poor contact with electrolytes, and bulk, due to a thick electrolyte) are a result of the rudimentary manufacturing capabilities that exist for solid-state electrolytes. In general, solid electrolytes are studied as flat pellets with planar interfaces, which minimizes interfacial contact area. Here, multiple ink formulations are developed that enable 3D printing of unique solid electrolyte microstructures with varying properties. These inks are used to 3D-print a variety of patterns, which are then sintered to reveal thin, nonplanar, intricate architectures composed only of Li 7 La 3 Zr 2 O 12 solid electrolyte. Using these 3D-printing ink formulations to further study and optimize electrolyte structure could lead to solid-state batteries with dramatically lower full cell resistance and higher energy and power density. In addition, the reported ink compositions could be used as a model recipe for other solid electrolyte or ceramic inks, perhaps enabling 3D printing in related fields. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chapter 6. Operation of electrolytic cell in standard operating practices

International Nuclear Information System (INIS)

Yanko, E.A.; Kabirov, Sh.O.; Safiev, Kh.; Azizov, B.S.; Mirpochaev, Kh.A.

2011-01-01

This chapter is devoted to operation of electrolytic cell in standard operating practices. Therefore, the electrolyte temperature, the composition of electrolyte, including the level of metals was considered. The regulation of electrolyte composition by liquidus temperature and electrolyte overheating was studied. Damping of anode effects was studied as well. Maintenance of electrolytic cells was described. Heat and energy balances of aluminium electrolytic cells were considered.

Plasma physics

CERN Document Server

Drummond, James E

1961-01-01

A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

Submerged Glow-Discharge Plasma: An Economical Approach to Convert Construction Scrap Metal into Nanomaterials

Science.gov (United States)

Yek, Peter Nai Yuh; Rafiq Mirza Julaihi, Muhammad; Shahril Osman, Mohammad; Tiong, Tung Chuan; Lee, Wak Ha; Leing Lee, Chern

2018-03-01

Submerged glow-discharge plasma (SGDP) is relatively new among the various methods available for nanomaterials synthesis (NMs) techniques. This method allows great control over the production cost of nanomaterials synthesis. A lab-scale batch type SDGP technology has been constructed to produce nanomaterials and investigate the inter-relationship between plasma excitation voltages, electrodes submerged areas and electrolyte concentration. Metal oxide nanospheres has been synthesised from different electrolyte concentrations (1M-0.001M) and characterized by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). As the major results showed that the nanospheres are uniformly spherical with diameter size distribution are between 100 nm - 2μm. EDS analysis shown the nano-Iron Oxide have been formed. Scrap metal initially showed around 6.45% and 93.55% of Carbon and Iron composition respectively. After SGDP process to the scrap metal, Carbon content has increased to 34-35% and Iron content has reduced to around 15-40%. EDS results also shown the higher percentage of Iron amount has remained with lower electrolyte concentration and Current is proportionally related to submersion area of cathode.

Salinity effects on plasma ion levels, cortisol, and osmolality in Chinook salmon following lethal sampling.

Science.gov (United States)

Stewart, Heather A; Noakes, David L G; Cogliati, Karen M; Peterson, James T; Iversen, Martin H; Schreck, Carl B

2016-02-01

Studies on hydromineral balance in fishes frequently employ measurements of electrolytes following euthanasia. We tested the effects of fresh- or salt-water euthanasia baths of tricaine mesylate (MS-222) on plasma magnesium (Mg(2+)) and sodium (Na(+)) ions, cortisol and osmolality in fish exposed to saltwater challenges, and the ion and steroid hormone fluctuations over time following euthanasia in juvenile spring Chinook salmon (Oncorhynchus tshawytscha). Salinity of the euthanasia bath affected plasma Mg(2+) and Na(+) concentrations as well as osmolality, with higher concentrations in fish euthanized in saltwater. Time spent in the bath positively affected plasma Mg(2+) and osmolality, negatively affected cortisol, and had no effect on Na(+) concentrations. The difference of temporal trends in plasma Mg(2+) and Na(+) suggests that Mg(2+) may be more sensitive to physiological changes and responds more rapidly than Na(+). When electrolytes and cortisol are measured as endpoints after euthanasia, care needs to be taken relative to time after death and the salinity of the euthanasia bath. Copyright © 2015 Elsevier Inc. All rights reserved.

Rebalancing electrolytes in redox flow battery systems

Science.gov (United States)

Chang, On Kok; Pham, Ai Quoc

2014-12-23

Embodiments of redox flow battery rebalancing systems include a system for reacting an unbalanced flow battery electrolyte with a rebalance electrolyte in a first reaction cell. In some embodiments, the rebalance electrolyte may contain ferrous iron (Fe.sup.2+) which may be oxidized to ferric iron (Fe.sup.3+) in the first reaction cell. The reducing ability of the rebalance reactant may be restored in a second rebalance cell that is configured to reduce the ferric iron in the rebalance electrolyte back into ferrous iron through a reaction with metallic iron.

Fuel cell assembly with electrolyte transport

Science.gov (United States)

Chi, Chang V.

1983-01-01

A fuel cell assembly wherein electrolyte for filling the fuel cell matrix is carried via a transport system comprising a first passage means for conveying electrolyte through a first plate and communicating with a groove in a second plate at a first point, the first and second plates together sandwiching the matrix, and second passage means acting to carry electrolyte exclusively through the second plate and communicating with the groove at a second point exclusive of the first point.

One-Step Fast-Synthesized Foamlike Amorphous Co(OH)2 Flexible Film on Ti Foil by Plasma-Assisted Electrolytic Deposition as a Binder-Free Anode of a High-Capacity Lithium-Ion Battery.

Science.gov (United States)

Li, Tao; Nie, Xueyuan

2018-05-23

This research prepared an amorphous Co(OH) 2 flexible film on Ti foil using plasma-assisted electrolytic deposition within 3.5 min. Amorphous Co(OH) 2 structure was determined by X-ray diffraction and X-ray photoelectron spectroscopy. Its areal capacity testing as the binder and adhesive-free anode of a lithium-ion battery shows that the cycling capacity can reach 2000 μAh/cm 2 and remain at 930 μAh/cm 2 after 50 charge-discharge cycles, which benefits from the emerging Co(OH) 2 active material and amorphous foamlike structure. The research introduced a new method to synthesize amorphous Co(OH) 2 as the anode in a fast-manufactured low-cost lithium-ion battery.

The impact of maternal plasma volume expansion and antihypertensive treatment with intravenous dihydralazine on fetal and maternal hemodynamics during pre-eclampsia: a clinical, echo-Doppler and viscometric study.

NARCIS (Netherlands)

Boito, S.M.; Struijk, P.C.; Pop, G.A.M.; Visser, W. de; Steegers, E.A.P.; Wladimiroff, J.W.

2004-01-01

OBJECTIVES: To establish the effects of plasma volume expansion (PVE) followed by intravenous dihydralazine (DH) administration on maternal whole blood viscosity (WBV) and hematocrit, uteroplacental and fetoplacental downstream impedance and umbilical venous (UV) volume flow in pre-eclampsia.

Chemical Passivation of Li(exp +)-Conducting Solid Electrolytes

Science.gov (United States)

West, William; Whitacre, Jay; Lim, James

2008-01-01

Plates of a solid electrolyte that exhibits high conductivity for positive lithium ions can now be passivated to prevent them from reacting with metallic lithium. Such passivation could enable the construction and operation of high-performance, long-life lithium-based rechargeable electrochemical cells containing metallic lithium anodes. The advantage of this approach, in comparison with a possible alternative approach utilizing lithium-ion graphitic anodes, is that metallic lithium anodes could afford significantly greater energy-storage densities. A major impediment to the development of such cells has been the fact that the available solid electrolytes having the requisite high Li(exp +)-ion conductivity are too highly chemically reactive with metallic lithium to be useful, while those solid electrolytes that do not react excessively with metallic lithium have conductivities too low to be useful. The present passivation method exploits the best features of both extremes of the solid-electrolyte spectrum. The basic idea is to coat a higher-conductivity, higher-reactivity solid electrolyte with a lower-conductivity, lower-reactivity solid electrolyte. One can then safely deposit metallic lithium in contact with the lower-reactivity solid electrolyte without incurring the undesired chemical reactions. The thickness of the lower-reactivity electrolyte must be great enough to afford the desired passivation but not so great as to contribute excessively to the electrical resistance of the cell. The feasibility of this method was demonstrated in experiments on plates of a commercial high-performance solid Li(exp +)- conducting electrolyte. Lithium phosphorous oxynitride (LiPON) was the solid electrolyte used for passivation. LiPON-coated solid-electrolyte plates were found to support electrochemical plating and stripping of Li metal. The electrical resistance contributed by the LiPON layers were found to be small relative to overall cell impedances.

Fire-extinguishing organic electrolytes for safe batteries

Science.gov (United States)

Wang, Jianhui; Yamada, Yuki; Sodeyama, Keitaro; Watanabe, Eriko; Takada, Koji; Tateyama, Yoshitaka; Yamada, Atsuo

2018-01-01

Severe safety concerns are impeding the large-scale employment of lithium/sodium batteries. Conventional electrolytes are highly flammable and volatile, which may cause catastrophic fires or explosions. Efforts to introduce flame-retardant solvents into the electrolytes have generally resulted in compromised battery performance because those solvents do not suitably passivate carbonaceous anodes. Here we report a salt-concentrated electrolyte design to resolve this dilemma via the spontaneous formation of a robust inorganic passivation film on the anode. We demonstrate that a concentrated electrolyte using a salt and a popular flame-retardant solvent (trimethyl phosphate), without any additives or soft binders, allows stable charge-discharge cycling of both hard-carbon and graphite anodes for more than 1,000 cycles (over one year) with negligible degradation; this performance is comparable or superior to that of conventional flammable carbonate electrolytes. The unusual passivation character of the concentrated electrolyte coupled with its fire-extinguishing property contributes to developing safe and long-lasting batteries, unlocking the limit toward development of much higher energy-density batteries.

Nanoscale Organic Hybrid Electrolytes

KAUST Repository

Nugent, Jennifer L.

2010-08-20

Nanoscale organic hybrid electrolytes are composed of organic-inorganic hybrid nanostructures, each with a metal oxide or metallic nanoparticle core densely grafted with an ion-conducting polyethylene glycol corona - doped with lithium salt. These materials form novel solvent-free hybrid electrolytes that are particle-rich, soft glasses at room temperature; yet manifest high ionic conductivity and good electrochemical stability above 5V. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nanoscale Organic Hybrid Electrolytes

KAUST Repository

Nugent, Jennifer L.; Moganty, Surya S.; Archer, Lynden A.

2010-01-01

Nanoscale organic hybrid electrolytes are composed of organic-inorganic hybrid nanostructures, each with a metal oxide or metallic nanoparticle core densely grafted with an ion-conducting polyethylene glycol corona - doped with lithium salt. These materials form novel solvent-free hybrid electrolytes that are particle-rich, soft glasses at room temperature; yet manifest high ionic conductivity and good electrochemical stability above 5V. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Recent results on aqueous electrolyte cells

KAUST Repository

Wessells, Colin; Huggins, Robert A.; Cui, Yi

2011-01-01

The improved safety of aqueous electrolytes makes aqueous lithium-ion batteries an attractive alternative to commercial cells utilizing flammable and expensive organic electrolytes. Two important issues relating to their use have been addressed

The buffer effect in neutral electrolyte supercapacitors

DEFF Research Database (Denmark)

Thrane Vindt, Steffen; Skou, Eivind M.

2016-01-01

The observation that double-layer capacitors based on neutral aqueous electrolytes can have significantly wider usable potential windows than those based on acidic or alkaline electrolytes is studied. This effect is explained by a local pH change taking place at the electrode surfaces, leading...... potassium nitrate as the electrolyte and potassium phosphates as the buffer system....

Plasma volume expansion does not increase maximal cardiac output or VO2 max in lowlanders acclimatized to altitude

DEFF Research Database (Denmark)

Calbet, José A L; Rådegran, Göran; Boushel, Robert Christopher

2004-01-01

liter of 6% dextran 70 (BV = 6.32 +/- 0.34 liters). PV expansion had no effect on Qmax, maximal O2 consumption (VO2), and exercise capacity. Despite maximal systemic O2 transport being reduced 19% due to hemodilution after PV expansion, whole body VO2 was maintained by greater systemic O2 extraction (P...... VO2 during exercise regardless of PV. Pulmonary ventilation, gas exchange, and acid-base balance were essentially unaffected by PV expansion. Sea......With altitude acclimatization, blood hemoglobin concentration increases while plasma volume (PV) and maximal cardiac output (Qmax) decrease. This investigation aimed to determine whether reduction of Qmax at altitude is due to low circulating blood volume (BV). Eight Danish lowlanders (3 females, 5...

Oligonol supplementation modulates plasma volume and osmolality and sweating after heat load in humans.

Science.gov (United States)

Lee, JeongBeom; Shin, YoungOh; Murota, Hiroyuki

2015-05-01

Oligonol is a low-molecular-weight polyphenol that possesses antioxidant and anti-inflammatory properties. This study investigated the effects of Oligonol supplementation on sweating response, plasma volume (PV), and osmolality (Osm) after heat load in human volunteers. We conducted a placebo-controlled crossover trial. Participants took a daily dose of 200 mg Oligonol or placebo for 1 week. After a 2-week washout period, the subjects were switched to the other study arm. As a heat load, half-body immersion into hot water (42°C±0.5°C for 30 min) was performed in an automated climate chamber. Tympanic and mean body temperature (Tty, mTb) and whole-body sweat loss volume (WBSLV) were measured. Changes in PV, Osm, and serum levels of aldosterone and sodium were analyzed. Oligonol intake attenuated increases in Tty, mTb, and WBSLV after heat load compared with the placebo (Pbody temperature and excessive sweating under heat load in healthy humans, but interpretation of the results requires caution due to the potent diuretic effect of Oligonol.

Smart coating process of proton-exchange membrane for polymer electrolyte fuel cell

International Nuclear Information System (INIS)

Leu, Hoang-Jyh; Chiu, Kuo-Feng; Lin, Chiu-Yue

2013-01-01

Highlights: ► Using oxygen plasma and smart coating technique for membrane modification. ► Oxygen plasma treatment can increase the reaction area of the membrane. ► AFM, SEM, FT-IR, XPS, EIS spectra can prove the surface treatment process. ► Nafion membrane modification can reduce Rct and enhance current density. - Abstract: The interfaces of electrolyte|catalyst|electrode play an important role in the performance of proton-exchange membrane fuel cells (PEMFCs). Increasing the interface effective area and lowering the charge transfer resistance of the interface are significant issues to promote the cell performance. In this study, oxygen plasma treatment was used to increase the surface roughness of Nafion®117 membrane, and then a smart coating process was applied to fabricate the initial Pt/C catalyst layer, which served to reduce the charge transfer resistance of the interface. The morphology and surface characteristics of membranes have been qualified by scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy. These results show that the plasma treatments and smart coating processes were effective in reducing the interface charge transfer resistance. At optimal condition, the interface charge transfer resistance was 0.45 Ω/cm 2 which was 1–2 order less than the untreated ones

Recovery of mercury from mercury compounds via electrolytic methods

Science.gov (United States)

Grossman, Mark W.; George, William A.

1988-01-01

A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg.sub.2 Cl.sub.2 employing as the electrolyte solution a mixture of HCl and H.sub.2 O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H.sub.2 O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds.

Improving rate capability and reducing over-potential of lithium-oxygen batteries through optimization of Dimethylsulfoxide-N/N-dimethylacetamide mixed electrolyte

International Nuclear Information System (INIS)

Chen, Chunguang; Li, Liangyu; Su, Junming; Zhang, Congcong; Chen, Xiang; Huang, Tao; Yu, Aishui

2017-01-01

Although dimethylsulfoxide (DMSO) solvent has been widely researched in rechargeable lithium-oxygen (Li-O 2 ) batteries, high polarization voltage and low rate capability limited its application. In this work, we reported a DMSO-based electrolyte system by adding N, N-dimethylacetamide (DMA) to adjust its physical and electrochemical properties. The ionic conductivity, viscosity, oxygen solubility and diffusion coefficient of the mixed electrolytes as well as their electrochemical performance in Li-O 2 batteries are researched. The electrochemical tests show that the optimized DMSO/DMA volume ratio is 30 to 70 based on the rate performance and polarization voltage of the cell. Compared with that of the pure DMSO-based electrolyte, the cell with the mixed electrolyte shows improved rate capability and reduced charge-discharge over-potential. When increasing current density from 0.2 to 0.5 mA cm −2 , the capability retention improves from 32% to 59%. Meanwhile, the charge-discharge voltage gap drops from 1.4V to 0.9V at a current density of 0.2 mA cm −2 . The improved electrochemical performance could be attributed to low viscosity, high oxygen solubility and diffusion coefficient as well as the low charge-transfer resistance with the mixed electrolyte.

State of art data acquisition system for large volume plasma device