British Library Electronic Table of Contents (United Kingdom)

This paper presents the results of the degree of irreversible changes of dielectric properties of vacuum circuit breakers with CuCr and CuBi contacts before and after short-circuit breaking operations. Tests of dielectric properties were performed on four different types of switching vacuum chamber with RMF electrodes in the form of a spiral disk with slots. The paper describes the configuration of measuring system for determining the dielectric properties of circuit breakers with DC, AC and pulse voltage. It also describes the measuring procedure. The results were analyzed and the experimentally obtained random variable breakdown voltage is found to belong to Weibull distribution in all cases. Based on these results it was found that for the vacuum circuit breakers with CuCr contacts and ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to investigate the feasibility and the optimal conditions of radiofrequency (RF) ablation by using the stent-type electrode upon the saphenous vein of goats for the endovenous treatment of varicose veins. A self-expandable nitinol stent electrode (6 mm diameter, 2 cm length, cell size; 1.3 x 2 mm) was designed to expose the distal 1 cm segment to allow for contact with the venous wall. The proximal part of the electrode was connected to the RF generator by insulated copper wires located within the stent electrode introducer. Initially, to optimize the power setting, ablation of 6 saphenous veins in 3 goats was performed with power settings of 10, 20 and 30 W. Pull back rate of the electrode was 2 and 4 cm/min for each power level, respectively. The goats were sacrificed 4-6 weeks later and histologic examinations of the saphenous ...

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A gas diffusion semiconductor electrode and solar cell and a process for gaseous fixation, such as nitrogen photoreduction, CO/sub 2/ photoreduction and fuel gas photo-oxidation are described. The gas diffusion photosensitive electrode has a central electrolyte porous matrix with an activated semiconductor material on one side adapted to be in contact with an electrolyte and a hydrophobic gas diffusion region on the opposite side adapted to be in contact with a supply of molecular gas.

Energy Technology Data Exchange (ETDEWEB)

The present volume on modeling of batteries and fuel cells discusses the significance of the effectiveness factor for flooded porous electrodes, active pore distribution spectroscopy for characterizing porous battery electrodes, the agglomerate model for porous electrodes, and dynamic-performance measurements of battery cells for electric vehicles and other applications. Attention is given to mathematical modeling of a primary zinc/air battery, mathematical modeling of Grace Li-TiS2 cells, modeling of electrocrystallization processes in battery systems, and rotating disk electrode studies in molten Li/K carbonate eutectic. Topics addressed include the variability of nickel oxide cathode dissolution in molten carbonate fuel cells, water transport properties of fuel cell ionomers, modeling water content effects in polymer electrolyte fuel cells, and computer algebra applied in ...

Energy Technology Data Exchange (ETDEWEB)

This invention relates to the production method of composite electrode substrate for fuel cell. An impermeable material is used for edge sealant. The sealant is put in the clearance between two electrodes consisting of porous carbon material via thermoplastic resin sheet, and heated while being pressed. This production method increases the adherence between the porous carbon bodies and reduces the contact resistivity at the joint interface. Consequently, it becomes possible to produce the composite electrode for fuel cell without separator, resulting in simplification of assembly work, weight reduction, and downsizing. The preferable porous carbon body is made from shrinkage-treated fiber. After sheet forming, the thermosetting resin is impregnated, and then it is burnt to carbonization. Or mixed sheet of rayon and acrylic fiber is laminated to be heated and pressed without impregnating the resin. The ...

Energy Technology Data Exchange (ETDEWEB)

Studies were conducted of the bifunctional oxygen electrode. The development of a rechargeable metal-oxygen (air) cell has been hampered to a great extent by the lack of a stable and cost effective oxygen electrode capable of use during both charge and discharge. The first type of bifunctional electrode consists of two distinct catalytifc layers. The oxygen reduction catalyst layer containing a supported gold catalyst is in contact with a hydrophilic nickel layer in which evolution of oxygen takes place. Loadings of gold from 0.5 to 1.0 mg/cm/sup 2/ were investigated; carbon, graphite, metal, and spinel oxides were evaluated as substrates. The second part of the research effort was centered on developing a reversible oxygen electrode containing only one catalytic layer for both reduction and evolution of oxygen. The work was directed specifically to the study of perovskite type of ...

Energy Technology Data Exchange (ETDEWEB)

The new generation of performing rechargeable lithium-ion batteries (``rocking-chair``-type) are penalized by important self-output phenomena linked with the use of highly oxidizing positive electrodes. In order to limit this problem in LiMn{sub 2}O{sub 4}/C batteries, two different passivation techniques were used in order to limit the surface contact between the positive electrode and the electrolyte. Thanks to these treatments, a significant reduction of the percentage of irreversible capacity losses is effectively observed. (J.S.) 3 refs.

Energy Technology Data Exchange (ETDEWEB)

the development of lithium metal batteries is hindered by the bad reversibility of the Li{sup +}/Li pair, due to dendrites formation which limits the amount of active matter and can generate short-circuits. The chemical and electrochemical phenomena which take place at the electrode/organic electrolyte interface lead to the formation of a complex passivation film which is of prime importance for the functioning of this type of batteries. The in-situ infrared reflection spectroscopy is well adapted to the chemical study of the passivation layer. Two different techniques were used: the substraction normalized interfacial transform infrared spectroscopy (SNIFTIRS) and the electro-chemically modulated infrared reflectance spectroscopy. These methods have shown that the passivation layer that develops on the surface of the lithium electrode in contact with organic solutions (propylene carbonate, ethylene carbonate and ...

Science.gov (United States)

Studies have been carried out to determine the possible physiological effects of contact with carbon black made by the thermal process. Contact was made by ingestion, skin application and/or inhalation. Ingestion and/or skin application do not appear to lead to any changes from the normal. Inhalation exposures do not produce pulmonary function changes (antemortem or postmortem studies) but may lead to moderate to severe "perifocal" emphysema in Rhesus monkeys (not observed in guinea pigs). Inhalation studies also suggest right ventricular septal and to a degree, left ventricular hypertrophy in Rhesus monkeys as an effect. Additional studies are necessary to support these finding and consideration must be given to the variability among exposed subjects as compared to controls. PMID:136503

International Nuclear Information System (INIS)

In this work, a focused ion beam (FIB) milling process has been developed to fabricate 50 nm Bi nanowire and transistor structures using FEI-200 dual beam FIB system. For the fabrication, 50 nm bismuth film was thermally evaporated through EBL patterned PMMA windows onto SiO_2 substrates with pre-defined contact pads. Bi nanowire widths ranging from 30 nm to 100 nm have been successfully fabricated by milling out unwanted areas using 30 KeV Ga+ ion beam. A single-pixel-line ion beam blanking technique has been utilised to fabricate Bi nanowire as small as 30 nm in diameter and few micrometers long. In order to form good ohmic contacts for sub 50 nm bismuth nanowires, a drill-and-fill process has been developed using FIB to sputter away the surface oxide of bismuth after the in-situ platinum nanowire contacts deposition. To our knowledge, this is the first time a focused ion beam process has been used to fabricate bismuth ...

Science.gov (United States)

Attempt to form the Schottky barrier on mercury indium telluride (MIT) surface by deposition transparent conducting electrode (TCE) and avoid the negative results by non-rectifier contacts nature, we have investigated the oxidation of clean MIT surfaces to form an insulating layer to overcome this disadvantage by metal-insulator-semiconductor (MIS) photodetectors designing. Oxide film is grown on the MIT surface by plasma enhance chemical vapor deposition (PECVD). Previously cleaned MIT wafers were dipped and boiled in solution, which consists of mixture of bromine and an organic solvent in ratio of 1:50. By the way of using these films as intermediate slightly conducting insulator, a fast-response MIT based surface-barrier photodetectors have been developed. Pt films were used as TCE frontal electrode by vacuum magnetron sputtering (VMS). The current-voltage characteristic is described quantitatively based on the energy ...

Energy Technology Data Exchange (ETDEWEB)

We demonstrate tuning of Schottky energy barriers in organic electronic devices by utilizing chemically tailored electrodes. The Schottky energy barrier of Ag on poly[2-methoxy], 5-(2{prime}-ethyl-hexyloxy)- 1,4-phenylene was tuned over a range of more than 1 eV by using self-assembled monolayers (SAM{close_quote}s) to attach oriented dipole layers to the Ag prior to device fabrication. Kelvin probe measurements were used to determine the effect of the SAM{close_quote}s on the Ag surface potential. {ital Ab} {ital initio} Hartree-Fock calculations of the molecular dipole moments successfully describe the surface potential changes. The chemically tailored electrodes were then incorporated in organic diode structures and changes in the metal/organic Schottky energy barriers were measured using an electroabsorption technique. These results demonstrate the use of self-assembled monolayers to control metal/organic interfacial electronic properties. ...

Science.gov (United States)

Cadmium telluride single crystals were grown heavily doped with chloride by the THM method. The resulting crystals were n-type with free carrier concentrations of the order of 10('12)/cm at room temperature. Hall effect studies revealed room temperature mobilities between 30 and 350 cm('2)/v-sec and resistivites between 2 x 10('3) and 10('4) ohm-cm. Studies were made of the gamma and alpha counting characteristics of these crystals with metal, metal-semiconductor, and metal-insulator electrodes. It was found that the MIS and MSS structures resulted in significant improvement over the MS structures in counting, signal-to-noise and energy resolution.

CERN Document Server

The controlled growth of nanowires (NWs) with dimensions comparable to the Fermi wavelengths of the charge carriers allows fundamental investigations of quantum confinement phenomena. Here, we present studies of proximity-induced superconductivity in undoped Ge/Si core/shell NW heterostructures contacted by superconducting leads. By using a top gate electrode to modulate the carrier density in the NW, the critical supercurrent can be tuned from zero to greater than 100 nA. Furthermore, discrete sub-bands form in the NW due to confinement in the radial direction, which results in stepwise increases in the critical current as a function of gate voltage. Transport measurements on these superconductor-NW-superconductor devices reveal high-order (n = 25) resonant multiple Andreev reflections, indicating that the NW channel is smooth and the charge transport is highly coherent. The ability to create and control coherent superconducting ordered states ...

Science.gov (United States)

PMID:4317460

Science.gov (United States)

A proposed metallization system for large area silicon solar cells with shallow junctions is outlined, and its desirable features are discussed. A baseline process sequence for the nickel palladium metallization system (NPMS) is delineated. This baseline process sequence is serving as the starting point from which process variations are being performed. The eventual goal is optimization of the NPMS process and determination of the control ranges for NPMS process variables. Initial studies of palladium displacement and electroless chemical plating solutions used in the baseline NPMS have begun and progress is reported. In support of this work, an annotated bibliography (45 citations) dealing primarily with palladium plating and palladium-silicon contact formation has been prepared (and will be subject to updating in the future reports).

Energy Technology Data Exchange (ETDEWEB)

Considerable interest has focused recently on the use of lignocellulosic fibers as a reinforcement for thermoplastic polymers. The combination of these dissimilar materials, however, is characterized by a widespread incompatibility that leads to a weak fiber/polymer interface and poor performance properties for the composite. In an effort to improve compatibility a number of fiber surface modification approaches have been investigated including plasma, ozone, and polymer grafting treatments. Evaluation of adhesion improvements has been complicated by processing variables that are difficult to control. This paper will discuss the use of the-micro-debond test in quantifying the interfacial shear strength (ISS) in wood fiber/polystyrene composites. Wood fibers were modified to different degrees with styrene-maleic anhydride copolymers that varied in their composition. The effect of fiber modification on surface energetics was determined using dynamic ...

British Library Electronic Table of Contents (United Kingdom)

In this study, bacterial strains were investigated in order to determine their heavy metal tolerance. The bacterial strains were identified as Bacillus cereus and Bacillus pumilus. In the batch system, the effects of operating variables such as solution pH, initial metal concentration, contact time, and adsorbent dosage were investigated. Both isolates were highly resistance to copper and lead in comparison with the control strain examined. The adsorption capacities of B. cereus and B. pumilus were found to be 22.1mg/g and 28.06mg/g, respectively. The biosorption follows pseudo-second order kinetics and the isotherm fits well to the Langmuir isotherm model. In column experiments, the biosorption was fitted well by the Thomas model. The breakthrough and exhaustion capacity of each biosorben...

Energy Technology Data Exchange (ETDEWEB)

Objective of the project is characterization of electrode reactions in molten salt by using metal oxides and silica-based electrode. The scope of project are characterization of metal oxide properties in molten salt and miniaturization of 3-electrode electrochemical test cell. Electrochemical micro-cell for actinide-LiCl-KCl molten salt was newly designed. Electroless and electrochemical deposition technique was applied to Mo coating on quartz tube. From the design of electrode and 3-electrode electrochemical cell suitable for the tests in molten salt electrolyte, so it is anticipated to get the information on the electrochemical behavior of metallic electrode in molten salt and to secure the information on oxidation/reduction behavior of actinide

Energy Technology Data Exchange (ETDEWEB)

We used light confinement in optical microcavities to achieve a strong enhancement and a precise wavelength tunability of the electrical photoconductance of nanostructured porous silicon (PS). The devices consist of a periodic array of alternating PS layers, electrochemically etched to have high and low porosities - and therefore distinct dielectric functions. A central layer having a doubled thickness breaks up the symmetry of the one-dimensional photonic structure, producing a resonance in the photonic band gap that is clearly observed in the reflectance spectrum. The devices were transferred to a glass coated with a transparent SnO{sub 2} electrode, while an Al contact was evaporated on its back side. The electrical conductance was measured as a function of the photon energy. A strong enhancement of the conductance is obtained in a narrow (17nm FWHM) band peaking at the resonance. We present experimental results of the angular dependence of ...

International Nuclear Information System (INIS)

Preparation and electrocatalytic reactions of nano porous materials in biodegradable fluids were studied. Electrochemical etching was conducted to selectively extract metallic elements from alloys to form porous structures. Electrocatalytic properties of the porous electrodes were characterized. Comparative studies on the electrochemical activities of the nano porous metallic electrodes with bulk metallic wire catalysts were performed. It is found that the current density at the nano porous electrode is three times higher than that of the bulk electrode

Science.gov (United States)

GEOTHERMAL TECHNOLOGIES LEGACY COLLECTION - Contact Us Geothermal Technologies Legacy Collection Help/FAQ | Site Map | Contact Us | Admin Log On Home/Basic Search About...

Energy Technology Data Exchange (ETDEWEB)

The invention comprises an improved rechargeable zinc-air cell/battery having recirculating alkaline electrolyte and a zinc electrode comprising a porous foam support material which carries the active zinc electrode material. 5 figs.

Energy Technology Data Exchange (ETDEWEB)

The geometrical and chemical effects of cerium (Ce) addition to Ni-Cr anode electrode in molten carbonate fuel cells (MCFCs) were investigated by measuring the fractal dimensions and wettability of four types of anode electrode with Ce added up to 5 wt.%. In addition, their cell performances were investigated through a single cell operation test and their results were explained based on the wettability of the anode electrodes. The addition of Ce to the anode electrode increased the fractal dimensions and wettabilities of the electrodes. Despite the even larger electrical resistivity of Ce compared to that of Ni and Cr, the electrical resistances of the Ce-added anode electrodes were slightly increased with increasing level of Ce addition. This might be ascribed to the greater wettability of the Ce-added anode electrode that enhanced the cell ...

KoreaScience (Korea)

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International Science & Technology Center (ISTC)

New Composite Multifunctional Coatings Produced Using SHS-Electrodes

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Science.gov (United States)

Not Available

International Nuclear Information System (INIS)

Results from a heavily fouled 19 tube C-E model boiler test to investigate the potential for egg crate corrosion in aggressively fouled AVT chemistry are reported. Substantial support plate and egg crate corrosion was produced in this test. Carbon steel drilled support plates exhibited extensive denting which resulted in flow hole ligament cracking. Corrosion of the carbon steel egg crate, through-wall at areas of tube contact, resulted in denting of the Alloy 600 heat transfer tubes. Corrosion performance of the 409 stainless steel egg crate was improved compared to the carbon steel egg crate although localized through-wall corrosion was noted. The results from the above test and previously reported tests were compared based on the following simplifying assumptions: maximum dent size and/or corrosion penetrations utilized, average bulk water chloride concentrations, pilling bedworth ratios, pot and model boilers data are equivalent, heat flux not significantly ...

Energy Technology Data Exchange (ETDEWEB)

The present invention concerns a negative ion source electrode which can be preferably used in a neutral particle injection device using negative ions for a thermonuclear reactor. Negative ion beams are deflected to the direction opposite to the deflecting direction by magnetic fields by using an electron suppression electrode having electrode holes with the position previously displaced before negative ion beams are accelerated to have a high energy by an accelerator thereby correcting the orbit of the negative ion beams easily. In addition, since the deflection correction electrode having the electrode holes is disposed, a proper voltage is applied to the deflection correction electrode to correct the orbit of the negative ion beams conveniently. Since the deflection correction electrode has a simple structure of a thin flat plate having ...

Energy Technology Data Exchange (ETDEWEB)

The key component for improving the energy efficiency and cycle life of the electrically rechargeable zinc-air battery is the bifunctional air electrode. The air electrodes described in this paper contained different types of carbon black as the substrate for the perovskite catalyst (La{sub 0.6}Ca{sub 0.4}CoO{sub 3}). Morphological and physical properties of the carbon substrates play an important role in enhancing the activity and stability of the bifunctional air electrode. Current-potential curves and cycle-life tests were applied in order to gather information on the activity and stability of these electrodes. (authors)

Science.gov (United States)

In this study, different proportions of silver-palladium alloy used as an inner electrode are adopted to fabricate (Zn,Mg)TiO3-based multilayer ceramic capacitors. Effects of sintering temperature, and measuring frequency on the dielectric properties of the samples with different proportions of the Pd-Ag inner electrode are investigated. The continuity of the inner electrode and the proportion of Pd-Ag of the inner electrode of samples sintered at different temperatures play important roles in determining the dielectric properties.

Energy Technology Data Exchange (ETDEWEB)

The Archean core of the Laramide Wind River uplift records evidence of at least three major granitoid-forming episodes. The oldest, the Dry Creek gneiss (DCG), was emplaced by 2.8 Ga and occupies the northeastern part of the range. Mafic, pelitic and ultramafic inclusions occur in the DCG. Elsewhere in the Wind River Mountains there is evidence for crustal components as old as 3.8 Ga. The Bridger batholith (BB), intruded at 2.67 Ga, is found in the west-central Wind River Mountains. The Wind River batholith (WRB) refers to the youngest Late Archean granodiorites and granites which are found throughout the range and includes granitoids previously name the Louis Lake, Bears Ears, Popo Agie, and Middle Mountain intrusions. Although granitoids of the Wind River batholith have been dated at 2.63 and 2.55 Ga, they are considered together here because there is a complete gradation in rock type and because definite intrusive contacts are scarce. The DCG, BB, and WRB each ...

Energy Technology Data Exchange (ETDEWEB)

Single-electrode transient behavior was measured mainly during the discharging process for a model cell of electric double layer capacitor with nano-porous carbon electrodes and reference electrode. Apparent conductivity in the cell, which we call `effective conductivity,` is determined with approximation of current in transient behavior to a one-dimensional electrophoretic model. A comparison of effective conductivity with conductivity of bulk solution suggests an interesting mechanism of transfer of electrolyte ions. The difference in transient behavior between various electrolyte ions was not conspicuous in spite of distinctive differences in conductivity of each bulk solution. The large pore diameter of the carbon electrode results in rapid transient behavior and such an electrode should be suitable for rapid charge and discharge. The effect of origin of carbon ...

Energy Technology Data Exchange (ETDEWEB)

A method is described of controlling an anodic protection system in a heat exchanger comprising: (a) installing at least one cathode within the heat exchanger, at least one cathode being aligned with the longitudinal axis of the heat exchanger and extending substantially along the length of the heat exchanger; (b) installing a first reference electrode within and at one end of the heat exchanger, the first reference electrode having a first controller having a set point for control and a power supply having an output creating an electrical potential between at least one cathode and the heat exchanger; (c) measuring the electrical potential of the heat exchanger with the first reference electrode; (d) operating the first controller in response to measurements made by the first reference electrode to change the output of the power supply; (e) installing a second reference electrode ...

UK PubMed Central (United Kingdom)

In Experiment I, lever pressing by squirrel monkeys was maintained under a sequence of variable-interval, multiple variable-interval variable-interval, and multiple variable-interval extinction schedules...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Thermal (gas) nitridation of stainless steel alloys can yield low interfacial contact resistance (ICR), electrically conductive and corrosion-resistant nitride containing surface layers (Cr{sub 2}N, CrN, TiN, V{sub 2}N, VN, etc.) of interest for fuel cells, batteries, and sensors. This paper presents results of proton exchange membrane (PEM) single-cell fuel cell studies of stamped and pre-oxidized/nitrided developmental Fe-20Cr-4V weight percent (wt.%) and commercial type 2205 stainless steel alloy foils. The single-cell fuel cell behavior of the stamped and pre-oxidized/nitrided material was compared to as-stamped (no surface treatment) 904L, 2205, and Fe-20Cr-4V stainless steel alloy foils and machined graphite of similar flow field design. The best fuel cell behavior among the alloys was exhibited by the pre-oxidized/nitrided Fe-20Cr-4V, which exhibited {approx}5-20% better peak power output than untreated Fe-20Cr-4V, 2205, and 904L metal stampings. Durability ...

Energy Technology Data Exchange (ETDEWEB)

The reduction of oxygen was studied in 0.1 M KCl at 70 deg. C using the rotating disk electrode (RDE) technique on platinum and electrodeposited ZnO thin film electrodes deposited on platinum substrates. In the absence of Zn{sup 2+} ions in solution, a Tafel slope of 139 mV dec{sup -1} was obtained, a value close to that measured on bare platinum electrode (133 mV dec{sup -1}) and ascribed to the limitation of the reaction rate by the first electron transfer. The main difference between the noble metal and the oxide electrode was a shift of the curves towards more negative potentials. In the presence of Zn{sup 2+} ions, the current density decreased significantly and the Tafel slope was measured at 282 mV dec{sup -1} showing that the electrode was partially blocked by zinc oxide formation reaction intermediates.

DEFF Research Database (Denmark)

Methylisothiazolinone (MI) used alone is a new preservative causing a high prevalence of contact allergy. The eliciting threshold of MI is unknown. The combination of MI and phenoxyethanol enhances the antimicrobial efficacy of MI.

UK PubMed Central (United Kingdom)

Purpose.Since 2002, six blind patients have undergone implantation of an epiretinal 4 × 4 electrode array designed to directly stimulate the remaining cells of the retina...Full Text Available

International Nuclear Information System (INIS)

In this paper, results on ozone production by atmospheric pulsed discharge, are reported. In the research, two types of ozonizer (Type I and Type II) have been used to investigate improvements of ozone concentration and production efficiency. The ozonizer has plane-to-plane metal electrodes structure, and pre-ionization electrodes are placed on the high voltage electrodes (Type I). In Type II, the surface of grounded electrode with 20 mm of width is covered partly by dielectric (thin rubber) with 11 mm of width, while the geometry of both metal electrodes is same to Type I. In the case of Type I, maximum concentration of about 100 ppm and maximum yield of 70 g/kWh were obtained at input power of 0.3 W. On the other hands, in the case of Type II, 800 ppm and 100 g/kWh were obtained at input power of 1.5 W. It was found that the ozone concentration and production yield were improved ...

UK PubMed Central (United Kingdom)

We present an algorithm to identify individual neural spikes observed on high-density multi-electrode arrays (MEAs). Our method can distinguish large numbers of distinct neural units, even when spikes...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This paper describes a new idea for zinc-air battery design. The novel idea is a porous zinc electrode surrounded with a supersaturated zincate solution. 3 figs. (JDH)

Energy Technology Data Exchange (ETDEWEB)

Electrode areas, for the bifunctional O{sub 2}-electrodes and the pasted Zn-electrodes, have been successfully scaled up from 25 cm{sup 2} up to 250 cm{sup 2}. A filter press type cell was used to measure the cycle life of larger electrodes (100 cm{sup 2}). Up to now, more than 100 charge-discharge cycles (900 hours) with these scaled up Zn/O{sub 2}-cells could be demonstrated. (author) 2 figs., 2 refs.

Energy Technology Data Exchange (ETDEWEB)

An improved ion funnel design is disclosed that decreases the axial RF (parasite) fields at the ion funnel exit. This is achieved by addition of one or more compensation electrodes after the conductance limit electrode. Various RF voltage profiles may be applied to the various electrodes minimizing the parasite axial potential wells. The smallest RF aperture that serves as the conductance limiting electrode is further reduced over standard designs. Overall, the ion funnel improves transmission ranges of both low m/z and high m/z ions, reducing RF activation of ions and decreasing the gas load to subsequent differential pumping stages.

Energy Technology Data Exchange (ETDEWEB)

This patent describes an improved zinc electrode for a rechargeable zinc-air battery comprising an outer frame and a porous foam electrode support within the frame which is treated prior to the deposition of zinc thereon to inhibit the formation of zinc dendrites on the external surface thereof. The outer frame is provided with passageways for circulating an alkaline electrolyte through the treated zinc-coated porous foam. A novel rechargeable zinc-air battery system is also disclosed.

Energy Technology Data Exchange (ETDEWEB)

The oxidation of sulfur dioxide in gas diffusion electrodes (GDE) in the presence of a homogeneous catalyst, potassium iodide, is investigated. The influence of this catalyst on the voltage-current (V-I) characteristics of the electrodes and the utilization of sulfur dioxide is determined. It is shown that when using the homogeneous catalyst potassium iodide, the utilization can reach 95-100%.

KoreaScience (Korea)

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Medline Plus

... for The Use of Contact Lenses In Industrial Environments Children's Vision Kids Welcome Here Infant's Vision Preschool ...

CERN Document Server

We investigate the equivariant cohomology of the natural torus action on a K-contact manifold and its relation to the topology of the Reeb flow. Using the contact moment map, we show that the equivariant cohomology of this action is Cohen-Macaulay, which is a generalization of equivariant formality for torus actions without fixed points. As a consequence, a generic component of the contact moment map is a perfect Morse-Bott function for the basic cohomology of the orbit foliation F of the Reeb flow. Assuming that the closed Reeb orbits are isolated, we show that the basic cohomology of F is trivial in odd degrees, and its dimension equals the number of closed Reeb orbits. We characterize the K-contact manifolds with minimal number of closed Reeb orbits as real cohomology spheres. We also prove a GKM type theorem for K-contact manifolds, which allows us to calculate the equivariant ...

Energy Technology Data Exchange (ETDEWEB)

A focused ion beam (FIB) system produces a final beam spot size down to 0.1 .mu.m or less and an ion beam output current on the order of microamps. The FIB system increases ion source brightness by properly configuring the first (plasma) and second (extraction) electrodes. The first electrode is configured to have a high aperture diameter to electrode thickness aspect ratio. Additional accelerator and focusing electrodes are used to produce the final beam. As few as five electrodes can be used, providing a very compact FIB system with a length down to only 20 mm. Multibeamlet arrangements with a single ion source can be produced to increase throughput. The FIB system can be used for nanolithography and doping applications for fabrication of semiconductor devices with minimum feature sizes of 0.1 .mu.m or less.

Energy Technology Data Exchange (ETDEWEB)

Ultrafine particles of Co-P were synthesized by direct ball milling of Co and P powders and also investigated as a reversible hydrogen storage electrode material. The electrochemical results demonstrated that the reversible charge-discharge capacity of the Co-P electrode can reach more than 300mAh/g. In addition, the cycling ability and high rate capability of the Co-P electrode are excellent with only 5% capacity decay after 100 cycles at a high rate of 300mA/g. The temperature-programmed desorption measurements (TPD) of the Co-P electrode revealed that the charge and discharge reactions of the Co-P electrode proceeds predominantly through electrochemical hydrogen storage mechanism and the electrooxidation of cobalt contributes only a negligible part to the reversible electrochemical capacity. (author)

CERN Document Server

We consider chemical reaction networks taken with mass action kinetics. The steady states of such a system are solutions to a system of polynomial equations. Even for small systems the task of finding the solutions is daunting. We develop an algebraic framework and procedure for linear elimination of variables. The procedure reduces the variables in the system to a set of "core" variables by eliminating variables corresponding to a set of non-interacting species. The steady states are parameterized algebraically by the core variables, and a graphical condition is given for when a steady state with positive core variables necessarily have all variables positive. Further, we characterize graphically the sets of eliminated variables that are constrained by a conservation law and show that this conservation law takes a ...

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the results of research conducted during the sixteen month continuation of a program to develop rechargeable zinc-air batteries for electric vehicles. The zinc-air technology under development incorporates a metal foam substrate for the zinc electrode, with flow of electrolyte through the foam during battery operation. In this ``soluble`` zinc electrode the zincate discharge product dissolves completely in the electrolyte stream. Cycle testing at Lawrence Berkeley Laboratory, where the electrode was invented, and at MATSI showed that this approach avoids the zinc electrode shape change phenomenon. Further, electrolyte flow has been shown to be necessary to achieve significant cycle life (> 25 cycles) in this open system. Without it, water loss through the oxygen electrode results in high-resistance failure of the cell. The Phase I program, which focused ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes zinc-air battery for electric vehicle (EV). This battery is composed of air electrode, zinc electrode, and alkali electrolyte. During the discharge, oxygen taken from the air is reduced at the air electrode, and zinc is dissolved at the zinc electrode. The whole reaction is formation of zinc oxide from oxygen and zinc. This is taken out to use as a secondary battery through exchange and regeneration, which is called mechanical charge. For Electric Fuel, discharged products in the zinc electrode from a spent EV are extracted by a vibrating crusher, and are dissolved in KOH to prepare zinc ion electrolyte. Thus, zinc is obtained through the electrolytic refining. Since the regenerated zinc is separated from the electrolytic electrode as a form of dendritic powder, it is recovered, treated by press molding, regenerated, and used as a zinc ...

Science.gov (United States)

Two enantioselective, potentiometric membrane electrodes (EPMEs) based on maltodextrins with different value of dextrose equivalent (DE) (maltodextrin I: DE 4.0-7.0; maltodextrin II: DE 16.5-19.5) were proposed for the assay of baclofen enantiomers in baclofen raw materials and from its pharmaceutical formulation, Norton-Baclofen tablets. The slopes of the electrode function of the proposed electrodes were 55.0 mV/pS-baclofen for maltodextrin I-based electrode and 59.0 mV/pR-baclofen for maltodextrin II-based electrode and the detection limits were 1.34 x 10(-6) mol l(-1) (S-baclofen) and 2.52 x 10(-10) mol l(-1) (R-baclofen), respectively. The surfaces of the electrodes are stable and easily renewable by simply polishing on alumina paper. PMID:15598435

International Nuclear Information System (INIS)

Analysis of steady-state and transient photoconductivity measurements at room temperature performed on c-axis oriented GaN nanowires yielded estimates of free carrier concentration, drift mobility, surface band bending, and surface capture coefficient for electrons. Samples grown (unintentionally n-type) by nitrogen-plasma-assisted molecular beam epitaxy primarily from two separate growth runs were examined. The results revealed carrier concentration in the range of (3-6)x10"1"6 cm"-"3 for one growth run, roughly 5x10"1"4-1x10"1"5 cm"-"3 for the second, and drift mobility in the range of 500-700 cm"2/(V s) for both. Nanowires were dispersed onto insulating substrates and contacted forming single-wire, two-terminal structures with typical electrode gaps of #approx =#3-5 #mu#m. When biased at 1 V bias and illuminated at 360 nm (3.6 mW/cm"2) the thinner (#approx =#100 nm diameter) nanowires with the higher background doping showed an abrupt ...

Energy Technology Data Exchange (ETDEWEB)

As part of studies into the siting of a deep repository for nuclear waste, Swedish Nuclear Fuel and Waste Management Company (SKB) has commissioned the Alternative Models Project (AMP). The AMP is a comparison of three alternative modeling approaches for geosphere performance assessment for a single hypothetical site. The hypothetical site, arbitrarily named Aberg is based on parameters from the Aespoe Hard Rock Laboratory in southern Sweden. The Aberg model domain, boundary conditions and canister locations are defined as a common reference case to facilitate comparisons between approaches. This report presents the results of a discrete fracture pathways analysis of the Aberg site, within the context of the SR 97 performance assessment exercise. The Aberg discrete fracture network (DFN) site model is based on consensus Aberg parameters related to the Aespoe HRL site. Discrete fracture pathways are identified from canister locations in a prototype repository design to the surface of ...

Energy Technology Data Exchange (ETDEWEB)

To develop oxygen electrodes for rechargeable metal-air batteries, the electrochemical behaviour of gas-diffusion-type carbon electrodes loaded with Pr-Mn-Fe-based perovskite-type oxides was examined for the reduction and evolution of oxygen in 8 M KOH at 60 C. Among the oxides tested, Pr{sub 0.2}Ca{sub 0.8}Mn{sub 0.1}Fe{sub 0.9}O{sub 3} gave the highest electrode performances, e.g., current densities of 275 mA/cm{sup 2} (for oxygen reduction) and 225 mA/cm{sup 2} (for oxygen evolution) at -300 and +650 mV vs. Hg/HgO, respectively. The electrode performances were found to depend on both the catalytic activity of the oxides for H{sub 2}O{sub 2} decomposition reaction and the amounts of oxygen desorbed from the oxides. Furthermore, it was confirmed that the small zinc-air battery including the gas-diffusion-type electrode loaded with Pr{sub 0.2}Ca{sub 0.8}Mn{sub 0.1}Fe{sub 0.9}O{sub ...

International Nuclear Information System (INIS)

In the present paper we propose a model of physical phenomena behind the front face of the electrodes in an impulse plasma accelerator. The model is based on the results of recent experimental observations and measurements. It correlates plasma dynamics with mechanism of phenomena in a column of pinching plasma. On the contrary to the previous model the current one suggests the series of relatively short pulses of metallic ions from the erosion of electrode material. Till now the pinch was treated rather as a nearly continuous source of metallic plasma, feeding the process with ions from the erosion of electrode material. (author)

British Library Electronic Table of Contents (United Kingdom)

In this paper we describe a Ni-Sn intermetallic material obtained via template electroplating synthesis. The structure and the morphology of this material are investigated by X ray diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses. We demonstrate that Ni-Sn behaves as a sub-micrometric electrode showing a favourable response when cycled in a lithium cell. The results here reported suggest that the template electroplating is a promising synthetic approach that can lead to an optimized structure and morphology of the Ni-Sn electrode, such as to confer it a role of a high capacity anode in advanced lithium ion batteries.

Science.gov (United States)

The applicability of isothermal solidification as a contacting method for solar cells was proved for the systems AgSn and AuIn. The process is advantageous in that it requires no fluxes, no inert gases, and no pretreatment of the components. The IE contac...

UK PubMed Central (United Kingdom)

Many patients are currently suffering from nickel (Ni)-induced allergic contact dermatitis (ACD). There have been few Korean studies dealing with the threshold of Ni-induced ACD and quantifying the...Full Text Available

Science.gov (United States)

Contact scanner system in Wolsung NPP(model ESE-1565) is an early '70 equipment, so most of components are obsolete. To make it 100% compatible, PCBs for this system is the main object of the study. Most of components used in the system are not available ...

UK PubMed Central (United Kingdom)

BackgroundProspective measures of high knee abduction moment during landing identify female athletes at high risk for non-contact anterior cruciate ligament injury....Full Text Available

International Nuclear Information System (INIS)

This paper provides a brief overview of the young, but rapidly growing field of spintronics. Its primary objective is to explain how as electrons tunnel through simple insulators such as MgO, wavefunctions of certain symmetries are preferentially transmitted. This symmetry filtering property can be converted into a spin-filtering property if the insulator is joined epitaxially to a ferromagnetic electrode with the same two-dimensional symmetry parallel to the interface. A second requirement of the ferromagnetic electrodes is that a wavefunction with the preferred symmetry exists in one of the two spin channels but not in the other. These requirements are satisfied for electrons traveling perpendicular to the interface for Fe-MgO-Fe tunnel barriers. This leads to a large change in the resistance when the magnetic moment of one of the electrodes is rotated relative to those of the other electrode. This ...

Energy Technology Data Exchange (ETDEWEB)

In an earlier publication we considered acceleration of plasma rings (Compact Torus). Several possible accelerator configurations were suggested and the possibility of focusing the accelerated rings was discussed. In this paper we consider one scheme, acceleration of a ring between coaxial electrodes by a B/sub theta/ field as in a coaxial rail-gun. If the electrodes are conical, a ring accelerated towards the apex of the cone undergoes self-similar compression (focusing) during acceleration. Because the allowable acceleration force, F/sub a/ = kappaU/sub m//R where (kappa < 1), increases as R/sup -2/, the accelerating distance for conical electrodes is considerably shortened over that required for coaxial electrodes. In either case, however, since the accelerating flux can expand as the ring moves, most of the accelerating field energy can be converted into kinetic energy of the ring leading to high ...

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cellulose casing material made by Food Products Division,. Union Carbide Corporation. tion of the anode from oxygen generated at the charging electrode. ...

International Nuclear Information System (INIS)

Russian 1985. p. 114. USSR Levitskaya, GD Ture, MF Lata, LP L'vovskij

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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.

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... thus can function as switches -6 ... Akkari, "Optical Channel Waveguide Switch and Coupler ... Wide-Band Guided Wave Acousto-Optic Bragg Diffraction ...

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In this work, a highly-sensitive polymeric membrane ion selective electrode for determination of tetracycline was constructed by using molecularly imprinted polymer (MIP) particles as quasi-ionophore. The water-compatible MIP particles targeting tetracycline were synthesized with tetracycline as a template molecule, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, 2,2?-azobisisobutyronitrile as an initiator and lanthanum ion as a mediator. Benefited from the distinctive performance of the quasi-ionophore and the optimized composition of the membrane and the inner filling solution, the lower detection limit of the electrode was decreased to about 1 ? 10?8 mol/l. It exhibited a good electrode slope 59.8 mV/decade near the theoretical Nernstian one, ...

International Nuclear Information System (INIS)

Portuguese 2008 2 p. Brazil Silva, Diogo Lima da Andrade, Leonardo

International Nuclear Information System (INIS)

It is well known that a protective film is formed on the graphite negative electrode in ethylene carbonate (EC) electrolyte solution. This film is lithium-ion conductive and protects the decomposition of the electrolyte solution. In the present paper, the electrode/electrolyte interfaces in lithium-ion rechargeable batteries were characterized by three-dimensional complex impedance plots, whose axes are real, imaginary parts and time. The film resistance R _s_e_i and charge transfer resistance R _c_t were determined for negative electrodes in EC/ethyl methyl carbonate (EMC) electrolyte solution, and the formation mechanisms of the interfacial film were discussed. Furthermore, the contributions of vinylene carbonate and ethylene sulfite, which are added into the electrolyte solution for the film formation, were investigated.

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Proton exchange membrane (PEM) fuel cells are energy sources that have the ... for H2 /02 PEM fuel cells because their catalysts have properties suitable for 0 ...

Energy Technology Data Exchange (ETDEWEB)

A dielectric-wall linear accelerator is improved by a high-voltage, fast rise-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. 12 figs.

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In recent years, interest in the development of a polymer electrolyte fuel cell (PEFC) has considerably increased due to its advantages (e.g., high power density) compared with other fuel cell systems, and its potentials to become the power plant for the next generation, nonpolluting automobile engine. For large scale application of fuel cells, low platinum loading electrode structures are necessary. An electrode based on a highly porous carbonized polyacrylonitrile foam material with very low platinum loading ({approximately} 13 {micro}g/cm{sup 2}) was prepared. The performance of this electrode for oxygen reduction was evaluated and compared with bulk platinum and glassy carbon electrodes.

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... Exercises: Day and Night Classroom Exercises: Pinhole Focusing 3D Vision and Eye Health < Contact Lenses Monovision Playlist: ...

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The results of the second phase of the program of developing low cost contacts to silicon solar cells using copper are presented. Phase 1 yielded the development of a plated Pd-Cr-Cu contact system. This process produced cells with shunting problems when they were heated to 400 C for 5 minutes. Means of stopping the identified copper diffusion which caused the shunting were investigated. A contact heat treatment study was conducted with Pd-Ag, Ci-Ag, Pd-Cu, Cu-Cr, and Ci-Ni-Cu. Nickel is shown to be an effective diffusion barrier to copper.

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... Precautions Comprehensive Eye and Vision Examination Nutrition Lutein Antioxidants & Age-Related Eye Disease Lutein and Zeaxanthin - Eye- ...

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International Nuclear Information System (INIS)

... biological variability body distribution kidneys labelled compounds lead 203

International Nuclear Information System (INIS)

Attention is given to the folowing topics: population I and II variable stars; LP variables, the sun, and mass determination; and predegenerate and degenerate variables. Particular papers are presented on alternative evolutionary approaches to the absolute magnitude of the RR Lyrae variables; the evolution of the Cepheid stars; nonradial pulsations in rapidly rotating Delta Scuti stars; dynamical models of dust shells around Mira variables; and pulsations of central stars of planetary nebulae.

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Accidents of free-rolling cars against walls with friction are special cases of the general problem of the dynamic behavior (elastic or plastic) of car motion. Using particle modeling of the car body it is shown that large rotations, contact friction and plastic deformations can be computed. Because of the limitations of FEM it is necessary to model the car as a system of mass points connected by central force systems which are non-linear. The wall is formulated as a rigid body producing constraints for the contacting particles, while the contact force is given by the defined force system. Every contacting particle produces a plastic impact on the wall. The friction force is proportional to the contact force and lies in the direction of the sliding velocity on the wall. Time integration is carried out using a second order Gear method. ((orig.))

International Nuclear Information System (INIS)

The structure of the layers formed on a silver electrode by the adsorption of pyridine, Cl"-, CN"- and SO_4"2"- is discussed. A comparison of the amount of the species adsorbed with their Raman spectra shows that there is no simple relation between the species concentration and the enhancement of the Raman intensity. Furthermore, the inhomogeneity of the layers is shown by Raman microscopy observations. These results lead the authors to propose the formation of a new species stabilized in the colloidal silver layer. The Raman enhancement could be explained by the existence of a resonance effect. (Auth.).

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The hydrogen evolution reaction (HER) was studied on Ni-P{sub x} electrodes containing 8 to 16 weight percent P prepared by potentiostatic deposition. The amount of P in the alloy varied with deposition potential. The activity of the electrodes was dependent on the P concentration, and the formation of a passive film. Cyclic voltametry was used to study the removal of this film. 3 refs.

International Nuclear Information System (INIS)

Silicon/carbon composite anode materials were prepared by pyrolyzing the phenol-formaldehyde resin (PFR) mixed with silicon and graphite powders. Scanning electron microscopic (SEM) observation showed that the morphology stability of the composite electrodes can be retained during cycling. A structure evolution mechanism is proposed to illuminate the enhancement of cycleability of the composite electrode. The composite used as anode material for lithium ion batteries possesses a reversible capacity of over 700 mAh/g.

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Because of its high energy density, compatibility with aqueous electrolytes and the low toxicity of its active materials, the zinc-air battery system is an interesting candidate for electric vehicle applications. The use of O{sub 2} from the air as a reactant requires a partially open cell construction and a technologically challenging air interface. This report describes the research and development program at the Paul Scherrer Institute which finally led to the demonstration of a durable, electrically rechargeable zinc-oxygen battery. In a first phase the research program was focused on the development of bifunctional oxygen diffusion electrodes and pasted zinc electrodes. The current-potential behaviour and the cycle life performance of anodes and cathodes was tested in single electrode measurements (three-electrode arrangements) as well as in complete monopolar zinc-oxygen and zinc-air cells. La{sub ...

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A comparison of the loss mechanisms in screen-printed solar cells relative to buried contact cells and cells with photolithography-defined contacts is presented in this paper. Model calculations show that emitter recombination accounts for about 0.5% absolute efficiency loss in conventional screen-printed cells with low-sheet-resistance emitters. Ohmic contact to high-sheet-resistance emitters by screen-printing has been investigated to regain this efficiency loss. Our work shows that good quality ohmic contacts to high sheet-resistance emitters can be achieved if the glass frit chemistry and Ag particle size are carefully tailored. The melting characteristics of the glass frit determine the firing scheme suitable for low contact resistance and high fill factors. In addition, small to regular Ag particles were found to help achieve a higher open-circuit voltage and maintain a low ...

CERN Document Server

voltammetric methods. This remained evident for varying extents of silver dissolution. Ag(111) electrodes were oxidised in 0.1 M KCIO sub 4 solutions by a single swept ORC of 0.77x10 sup - sup 3 C cm sup - sup 2. The final rest potential of the Ag(111) working electrode was over the potential range of -36 mV to 114 mV versus the SCE where the silver islands of the reformed surface are believed to be unstable. Results show that a majority of silver islands of all sizes are stable with time, whereas the silver islands with irregular shapes tended to evolve to exhibit higher degrees of spherical geometry. Additionally, the position of the silver islands did not remain constant during the acquisition of STM images. Results from in situ STM demonstrated that the underlying step-terrace morphology of the Ag(111) electrodes did not remain constant with time. Both macroscale and nanoscale changes to the Ag(111) ...

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Carbons derived from the phase separation of polyacrylonitrile/solvent mixtures were investigated as lithium intercalation anodes for rechargeable lithium-ion batteries. The carbon electrodes have a bulk density of 0.35-0.5 g/cm{sup 3}, relatively low surface areas (< 10 m{sup 2}/g), and micron-size cells. Pyrolysis temperature influences the reversible lithium intercalation and the irreversible capacity (associated with the formation of the passivating layer). Carbon electrodes pyrolyzed at 600{degrees}C have first-cycle capacity as high as 550 mAh/g as well as large irreversible capacity, 440 mAh/g. Electrodes prepared at 1050{degrees}C have reversible capacities around 270 mAh/g with relatively lower capacity losses (120 mAh/g). Doping the organic precursors with phosphoric acid, prior to pyrolysis at 1050{degrees}C, leads to carbon electrodes with reversible capacities as high as 450 mAh/g. The ...

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There are two types of ionization chamber using magnetically levitated electrode: one is that by Tanaka et al. and the other, by authors'. The latter lacks the sensitivity relative to the former and thereby to solve the problem, authors made an improvement so that the electrode charge could be readout by noncontact after the leviated electrode was electrified by noncontact for an interval. This new type ionization chamber made it possible to measure the quite low dose radiation with stability and high sensitivity. Actually, the electrode was suspended by the teflon thread fixed on the steel cup levitated magnetically in the ionization chamber of which wall was covered by Al and equipped with an electrostatic charger for the electrode by noncontact. After measurement, the electrode was moved in the Faraday cage placed under the chamber to readout the ...

UK PubMed Central (United Kingdom)

A common property of aging in all animals is that chronologically and genetically identical individuals age at different rates. To unveil mechanisms that influence aging variability, we identified markers...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundDue to the increased accuracy of Copy Number Variable region (CNV) break point mapping, it is now possible to say with a reasonable degree of confidence whether a gene...Full Text Available

UK PubMed Central (United Kingdom)

Background/AimsTo explore different definitions of intra-individual variability (IIV) to summarize performance on commonly utilized cognitive tests (Mini Mental State Exam; Clock...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundVariable platelet response to clopidogrel has been widely observed. Studies have shown that the mean aggregation response to clopidogrel can be changed...Full Text Available

UK PubMed Central (United Kingdom)

A common approach used to fuse simultaneously recorded EEG and fMRI is to correlate trial-by-trial variability in the EEG, or variability of components derived therefrom, with the blood oxygenation...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This paper presents recent results concerning the chemical and electrochemical synthesis, the electrochemical properties and the characterization of two new families of amorphous oxides of formula Li{sub x}MVO{sub 4} (1electrodes in high performance lithium-ion batteries. (J.S.) 19 refs.

Energy Technology Data Exchange (ETDEWEB)

New results for two types of nano-size silicon, prepared via thermal vapour deposition either with or without a graphite substrate are presented. Their superior reversible charge capacity and cycle life as negative electrode material for lithium-ion batteries have already been shown in previous work. Here the lithiation reaction of the materials is investigated more closely via different electrochemical in situ techniques: Raman spectroscopy, dilatometry and differential electrochemical mass spectrometry (DEMS). The Si/graphite compound material shows relatively high kinetics upon discharge. The moderate relative volume change and low gas evolution of the nano silicon based electrode, both being important points for a possible future use in real batteries, are discussed with respect to a standard graphite electrode. (author)

Science.gov (United States)

This paper discusses the mechanisms of gas breakdown at low values of pressure and inter-electrode gap, i.e. in the vicinity of the Paschen minimum. In this area of pressure and inter-electrode gap values, breakdown occurs either through gas or vacuum mechanisms, and also the so called anomalous Paschen effect appears. Electrical breakdown of electropositive, electronegative and noble gases has been investigated theoretically, experimentally and numerically. Based on the results obtained, regions in which particular breakdown mechanisms appear have been demarcated. Special attention has been devoted to the anomalous Paschen effect as well as to the avalanche vacuum breakdown mechanism.

British Library Electronic Table of Contents (United Kingdom)

Abstract Hybrid power plants consisting of a solid oxide fuel cell (SOFC) and a gas turbine show high electrical efficiencies, however require pressurisation of the SOFC to several bar. This paper presents a theoretical investigation of the pressure influence on SOFC performance and durability. A two-dimensional elementary kinetic model is used to predict the performance of a single cell in the pressure range of 1-20-bar. The influence of pressure on thermodynamics, reaction kinetics, porous electrode diffusion, channel transport and efficiency is assessed. It was found that polarisation resistance decreases with increasing pressure due to increased diffusion through porous electrodes and a higher electrode surface coverage with reactant species. Furthermore, open-circuit voltage increases...

Energy Technology Data Exchange (ETDEWEB)

We demonstrate control and improvement of charge injection in organic electronic devices by utilizing self-assembled monolayers (SAMs) to manipulate the Schottky energy barrier between a metal electrode and the organic electronic material. Hole injection from Cu electrodes into the electroluminescent conjugated polymer poly[2-methoxy,5-(2{sup {prime}}-ethyl-hexyloxy)-1,4-phenylene vinylene] was varied by using two conjugated-thiol based SAMs. The chemically modified electrodes were incorporated in organic diode structures and changes in the metal/polymer Schottky energy barriers and current{endash}voltage characteristics were measured. Decreasing (increasing) the Schottky energy barrier improves (degrades) charge injection into the polymer. {copyright} {ital 1997 American Institute of Physics.}

British Library Electronic Table of Contents (United Kingdom)

An electrochemical biosensor for determination of hydrogen peroxide (H2O2) was fabricated, based on the electrostatic immobilization of horseradish peroxidase (HRP) with one-dimensional gold nanowires (Au NWs) and TiO2 nanoparticles (nano-TiO2) on a gold electrode. The nano-TiO2 can give a biocompatible microenvironment and compact film, and the Au NWs can provide fast electron transferring rate and greatly add the amount of HRP molecules immobilized on the electrode surface. Au NWs were characterized by ultraviolet?visible spectra and transmission electron microscope. The electrode modification process was probed by cyclic voltammetry and electrochemical impedance spectroscopy. Chronoamperometry was used to study the electrochemical performance of the resulting biosensor. Under optimal co...

Energy Technology Data Exchange (ETDEWEB)

Abstract not provided

International Nuclear Information System (INIS)

A theory of the asymptotic functions for the case of many variables is presented. It is shown that the class F(R"N) of these generalized functions is closed in respect to the linear algebraic and analytic operations, multiplication as well as a set of linear and polynomial changes of the variables. The existence in F(R"N) of analogues (consistent with the linear operations) of the Schwartz distributions with point support is proved. In terms of these analogues, some formulae for singular products and changes of variables of the Dirac #delta#-function and its derivatives #delta#"("i")(x), x is an element of R"N, are given. (author). 14 refs.

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... So whatever banking issues you would like to discuss, there are a number of convenient ways to contact us. You write to us, phone one of our UK call centres, arrange a meeting with a financial adviser or, of course, visit your local branch. Telephone us Want to give us a call? Click here to see our full list of contact details. Remember, all our call centres are based in the UK. So we can deal with your call efficiently, please have all ...

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Success in improving hydropower project efficiency has opened more global markets for variable-speed generator technology. Manufacturers continue to test the markets as the technology evolves. The potential of variable-speed application becomes evident considering that more than 150 pumped storage plants, with a combined capacity exceeding 100,000 MW, are in operation globally.

CERN Document Server

In this paper, we derive the moderate deviation principle for stationary sequences of bounded random variables with values in a Hilbert space. The conditions obtained are expressed in terms of martingale-type conditions. The main tools are martingale approximations and a new Hoeffding inequality for non adpated sequences of Hilbert-valued random variables. Applications to Cramer-Von Mises statistics, functions of linear processes and stable Markov chains are given.

International Nuclear Information System (INIS)

In recent years there has been a renewed interest in the treatment of quantum mechanics in terms of joint distribution functions, i.e. functions of momentum and position coordinates p and q. The author considers j.d.f. in the sense of classical probability theory of a stochastic variable. The j.d.f. is then interpreted as the probability that the variables p and q have certain values, the variables being considered as a property possessed by the object system. This formalism is used to provide a unified description of bradyons and tachyons. (Auth.).

Science.gov (United States)

Respiration and related physiologic variables in different tissues of Barytelphusa guerini and the respiration of this freshwater crab as a whole are closely synchronized in phase and in frequency along the circadian scale, in the face of large differences in circadian amplitude. A very close timing of most of the 36 variables examined in 2 separate circadian profiles and a modulation of some of these variables in added profiles as a function of lunar stage are clearly demonstrable, statistically significant and illustrative of time relations at 2 interacting frequencies. PMID:6745009

Science.gov (United States)

to Cool Spots Hanford Fun Facts Classroom Projects Famous People of Hanford Counterintelligence Home Employee Responsibilities CI Information CI Resources Points of Contact...

British Library Electronic Table of Contents (United Kingdom)

A stable BSA blocking poly(dimethylsiloxane) (PDMS) microchannel was prepared based on in situ synthesized PDMS-gold nanoparticles composite films. The modified microchip could successfully suppress protein adsorption. The assembly was followed by contact angle, charge-coupled device (CCD) imaging, electroosmotic flow (EOF) measurements and electrophoretic separation methods. Contact angle measurements revealed the coated surface was hydrophilic, water contact angle for coated chips was 45.2^o compared to a water contact angle for native PDMS chips of 88.5^o. The coated microchips exhibited reproducible and stable EOF behavior. With FITC-labeled myoglobin incubation in the coated channel, no fluorescence was observed with CCD image, and the protein exhibited good electrophoretic effect in ...

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... fl.biology.usgs.gov/herps/Frogs_and_Toads/R_virgatipes/r_virgatipes.html Page Contact Information: SESC Webmaster Page ... ...

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... fl.biology.usgs.gov/herps/Frogs_and_Toads/R_clamitans/r_clamitans.html Page Contact Information: SESC Webmaster Page ... ...

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may experience difficulty opening the Facebook page due to current HHS policy and network security that blocks access to the site. Site Map - Contact Us - Linking to USPHS.gov -...

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... d Diameter of ro.'ling element of a cylindrical roller bearing ... L Life (B-10) of a cyl.ndrical roller bearing LACA Contact ratio ...

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... keyboards, door knobs and counter tops, such surfaces should be cleaned with common household disinfectants regularly and after increased crowd contact. ...

UK PubMed Central (United Kingdom)

Because the proportion of Hispanic patients is increasing rapidly, most physicians are now coming into daily contact with Hispanics. In addition to obvious difficulty with oral communication, Hispanics...Full Text Available

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GEOTHERMAL TECHNOLOGIES LEGACY COLLECTION - Related Links Geothermal Technologies Legacy Collection Help/FAQ | Site Map | Contact Us | Admin Log On Home/Basic Search About...

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Summary brochure of GeoPowering the West (GPW) activities, and areas of technology transfer and market transformation. It also provides current contact information for key DOE and national laboratory staff representing the GPW program.

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... Environmental Assessment of Proposed Effluent Limitations Guidelines and Standards for the Meat and Poultry Industry Point Source; EPA-821-B-01-008; US ...

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In this paper, a complete solution of the steady-state Newton-Euler equations describing the motion of the balls in high speed thrust bill bearings is presented. Kinematic equations are derived and used as ancillary equations to obtain the numerical solution of the Newton-Euler equations. This differs from previously reported work where extraneous assumptions (instead of kinematic analysis) are used to allow solutions of these equations. It is shown that the no-slip condition for the ball motion reported in the literature is based on an unnecessary assumption. The correct form of the condition is developed and used in the analysis of the ball motion. The analysis shows the importance of contact angle on both ball motion and contact force. An approximate theory is then developed for determining the optimum contact angle that would result in minimum contact force in high speed ball bearings. The results ...

Energy Technology Data Exchange (ETDEWEB)

The Anglo-Danish programme of research on materials for advanced vehicular transport and other storage batteries is about to enter its fifth year. Here, the results of the work to date on solid electrolytes, electrode materials and cell design are reviewed and discussed as a systematic programme of cell testing gets underway.

Science.gov (United States)

Graphene nanosheets (GNSs) were synthesized and used as cathode active materials in a nonaqueous lithium-oxygen battery. The GNSs electrode delivered an extremely high discharge capacity in comparison to carbon powders, which is attributed to its unique morphology and structure. PMID:21779551

British Library Electronic Table of Contents (United Kingdom)

This study investigates the applicability of n-type TiO2 and p-type NiO on the FTO-glass (Fluorine doped tin oxide, SnO2:F) substrate of the working electrode in a dye-sensitized solar cell (DSSC). The working electrode was designed and fabricated by depositing a film of TiO2/NiO composite particles, which were prepared by mixing the Ni powder with TiO2 particles using dry mixing method, on a FTO-glass substrate using a spin coating process. The working electrode was then immersed in the solution of N-719 (Ruthenium) dye at a temperature of 70degreeC for 6h. Moreover, a thin film of platinum (Pt) was deposited on the FTO-glass substrate of the counter electrode using an E-beam evaporator. Finally, the DSSC was assembled, and the short-circuit photocurrent, the open-circuit photovoltage and...

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Stripping Voltammetry (SV) at microelectrodes has gained increased interest in the analysis of aqueous solutions due to its ability to analyze low concentrations (ppb) of electroactive metallic species in solution. Existing integrated circuit (IC) technology allows the inexpensive fabrication of microelectrodes with dimensions on the order of microns and with a high degree of uniformity and reproducibility. Additional circuitry, both multiplexing and signal conditioning, can be placed directly onto the sensor offering increased sensitivity and flexibility. Multi-element electrochemical sensors containing arrays of Pt, Au, and Ag electrodes and capable of individual measurement through built-in multiplexing or simultaneous measurement at the appropriate potential ranges for each individual electrode were fabricated using existing 2 micron IC technology. Results of simultaneous measurements of low concentrations of Cd, Pb, Cu, As, and Hg in ...

Energy Technology Data Exchange (ETDEWEB)

Previously we have used atomic force anodisation lithography, with a self-assembled monolayer of hexadecyltrichlorosilane as a resist, to pattern silicon oxide nanostructures onto a p-type silicon (1 0 0) substrate. A condensation reaction was used to immobilise carbon nanotubes with high carboxylic acid functionality directly to the silicon oxide. A further condensation reaction using this surface attached the molecule ferrocenemethanol to the bound nanotubes. These new nanostructures were used as electrodes to observe the oxidation and reduction of ferrocene. However, because the small currents measured are near the detection limits of the electrochemical system used, important electrode kinetics could not to be obtained. A scribing approach made larger regions of oxidised silicon leading to the creation of larger scale patterned arrangements of carbon nanotubes allowing measurement of important electrochemical parameters such as ...

UK PubMed Central (United Kingdom)

A type of electromyographic activity, formerly referred to as "pseudomyotonia", can be recorded from the striated muscle of the urethral sphincter using a concentric needle electrode. There are two...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Lithium, with its strong reducing property and very low potential (-3.045 V/ENH), is one of the best material for electrodes. By combining lithium with an oxidizer, one can obtain an energy and electromotive force higher than with any other electrochemical couple. The density of lithium is low (0.534 g/cm{sup 3}) and thus, its specific capacity is higher than other classical anode materials. This article presents the technology of lithium batteries: 1 - presentation; 2 - negative electrodes: metallic lithium based, lithiated carbon based, transition metal compounds based negative electrodes; 3 - positive electrodes: 'low' voltage and 'high' voltage cathode materials; 4 - electrolytes: introduction, organic solvents and lithium salts-based electrolytes (case of the lithium anode battery, case of the lithium-ion battery), polymer electrolytes; 5 - metallic lithium anode ...

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The gel electrolyte for the zinc-air cell was prepared by mixing hydroponics gel with a 6M potassium hydroxide aqueous solution. The self-discharge of cells was characterized by measuring the open-circuit voltage. The effect of a discharge rate of 50mA constant current on cell voltage and plateau hour, as well as the voltage-current and current density-power density were measured and analysed. The electrode degradation after discharge cycling was characterized by structural and surface methods. The oxidation of the electrode surface further blocked the utilization of the Zn anode and was identified as a cause for the failure of the cell. (author)

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A numerical model has been developed to simulate the charging and discharge behaviour of an electrically rechargeable alkaline zinc-air battery. Further a galvanostatic experiment including three charge/discharge cycles has been performed. The cell voltages, the Zn electrode potentials versus a Zn reference, and the O{sub 2} electrode potentials versus a Zn reference calculated with the model are in fairly good agreement with the corresponding experimental data. The model is expected to be useful for zinc-air battery design and for analysis of experimental data. (author)

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The cathodic electrode process of Y(3+) ions on the Mo electrode in the LICl-KCl molten salt with YCl3(3wt%) in the temperature range of 450 - 530 deg. C has been investigated using cyclic voltammetry and chronopotentiometry. The convolution technique has been applied to the treatment of cyclic voltammogram. The results show that the reduction mechanism of Y(3+) ion is Y(3+) + 3e = Y, a simple one-step process. The cathodic process is very close to a reversible process under lower scanning rates, and is diffusion-controlled. The cathodic product is an insoluble product.

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In order to improve the capacity and service life of cathodes, the effect of carboxy-methyl cellulose, soot, silica gel and fibres was examined. Structural tests and electrical and electro-chemical measurements are used for this. The additives can affect crystallization in the manufacturing stage of the electrodes and can increase the storage capacity for water and the electronic conductivity. They act to stabilize the mass in cyclic operation. Soot additive has little effect on the properties of the electrode, but the other substances increase the service life or the use of the mass. (LU).

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For the development of a rechargeable zinc/air battery, La{sub 0.6}Ca{sub 0.4}CoO{sub 3}-catalyzed (perovskite) bifunctional oxygen electrodes and pasted zinc electrodes were prepared and tested in monopolar zinc/air cells. The cells were cycled in moderately alkaline electrolyte. The maximum power as well as the cycle life of the cells were investigated. Up to 450 cycles could be reached, and attractive specific energies and powers were obtained. (author) 3 figs., 4 refs.

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Spherical {beta}-Ni(OH){sub 2} was modified by a low-cost method of normal ball milling (NBM), and the physical properties of both ball-milled and un-milled Ni(OH){sub 2} were characterized by transmission electron microscopy, specific surface area, particle size distribution and X-ray diffraction. It was found that NBM could obviously increase the surface area, decrease the particle and crystallite size, and reduce the crystallinity of {beta}-Ni(OH){sub 2}, which were advantageous to the improvement of the electrochemical activity of Ni(OH){sub 2}. NBM also lowered the packing density and flowability of Ni(OH){sub 2}, as revealed by the measurements of tapping density and angle of repose. Electrochemical performances of pasted nickel electrodes with an addition of ball-milled Ni(OH){sub 2} to spherical Ni(OH){sub 2} as the active material were investigated, and were compared with those of the pure spherical Ni(OH){sub 2} electrodes. ...

International Nuclear Information System (INIS)

Ultra low loading noble metal (0.04-0.12 mg_P_t/cm"2) based electrodes were obtained by direct metallization of non-catalyzed gas diffusion layers via dual ion beam assisted deposition (IBAD) method. Fuel cell performance results reported earlier indicate significant improvements in terms of mass specific power density of 0.297 g_P_t/kW with 250 A thick IBAD deposit (0.04 mg_P_t/cm"2 for a total MEA loading of 0.08 mg_P_t/cm"2) at 0.65 V in contrast to the state of the art power density of 1.18 g_P_t/kW using 1 mg_P_t_(_M_E_A_)/cm"2 at 0.65 V. In this article we report the peroxide radical initiated attack of the membrane electrode assembly utilizing IBAD electrodes in comparison to commercially available E-TEK (now BASF Fuel Cell GmbH) electrodes and find the pathway of membrane degradation as well. A novel segmented fuel cell is used for this purpose to relate membrane degradation to peroxide ...

International Nuclear Information System (INIS)

A super-hydrophobic coating was prepared by combining a rigid base film with crater-like hemispherical holes and acicular nanoparticles. The acicular boehmite powder provides a high contact angle on the film surface. The rigid base film with crater-like hemispherical holes inhibits the rapid decrease of contact angle by surface rubbing. The combination of different roughness is an effective method for improving the abrasion resistance of super-hydrophobic films.

International Nuclear Information System (INIS)

Thermally recyclable Nb point-contact Josephson junctions are investigated as low-noise mixers with an external local oscillator at 115 GHz. The best single sideband mixer noise temperature achieved is 140 ( +- 20) K with a (SSB) conversion loss of 2.4 ( +- 0.5) dB. Such rugged junctions are suitable for use in practical receivers and should give unprecedented sensitivity at the shorter millimeter wavelengths.

International Nuclear Information System (INIS)

The invention concerns a container for the long term storage of irradiated nuclear reactor fuel elements, which consists mainly of a basic body, at least one lid and an outside ring shaped lid tightening device, which acts on the basic body and the lid and holds the contact surface of the lid tight against the contact surface of the basic body, where the basic body, lid and the lid tightening device consist of corrosion-proof materials. (orig./HP).

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The contents of this report covers: (1) development of optimal geometries for crowned helical gears; (2) a method for their generation; (3) tooth contact analysis (TCA) computer programs for the analysis of meshing and bearing contact of the crowned helical gears; and (4) modelling and simulation of gear shaft deflection. The developed method for synthesis was used to determine the optimal geometry for a crowned helical pinion surface and was directed to localize the bearing contact and guarantee favorable shape and a low level of transmission errors. Two new methods for generation of the crowned helical pinion surface are proposed. One is based on the application of a tool with a surface of revolution that slightly deviates from a regular cone surface. The tool can be used as a grinding wheel or as a shaver. The other is based on a crowning pinion tooth surface with predesigned transmission errors. The pinion tooth surface ...

International Nuclear Information System (INIS)

Intensive work has long been going on to find out the unknown origin that sets off curious tribo-physicochemical phenomena and that causes various kinds of problems in oil-lubricated sliding contacts in mechanical and processing systems. The strange tribochemical reaction is one of the such curious chemical phenomena observed in the degradation of perfluoropolyether (PFPE) lubricating oil film in a hard disk drive. Plasma (triboplasma) (Nakayama and Mirza 2006 Tribol. Trans. 49 17) would be one of the most probable origins of the problems if it were generated sufficiently intensely in oil-lubricated sliding contacts, as it is in such a highly energetic state. The generation of plasma was predicted in both dry and oil-lubricated sliding (Nakayama 1997 Japan. J. Tribol. 42 1077, Nakayama 2004 Surf. Coat. Technol. 188-189 599). However, plasma generation in industrially important oil-lubricated contacts has not yet been ...

British Library Electronic Table of Contents (United Kingdom)

This research investigates the impact of national culture and several institutional factors on the safety performance of society and establishes statistically significant relationships between those variables. As expected, the research results reveal that some cultural variables such as uncertainty avoidance, gender orientation and institutional variables such as the degree of law avoidance can directly influence the safety performance of the society. The findings also support the inverted u-curve (Safety Kuznet curve) hypothesis indicating even if we expect a negative trend at the beginning stage of industrialization, we can expect a positive trend in safety performance as their income level continues to improve beyond a certain point.

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Creep properties of modified 9 Cr-1 Mo steel, an alloy significantly improved in elevated-temperature strength over 2 1/4 Cr-1 Mo and other similar alloys, are presented here. Data are primarily on material in the normalized and tempered condition. Effects of variables such as isothermal annealing treatment, cold work, normalizing temperature, tempering temperature, notch, and biaxial stress state have also been examined. Data analysis and comparisons have shown that modified 9 Cr-1 Mo alloy is very insensitive in response to several material variables, heat treatments, and specimen design variables.

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We report on studies of device degradation in organic photovoltaic devices based on blends of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM). Since delamination, oxidation, and chemical interactions at the metal electrode/organic interface have long been posited as degradation pathways in organic electronic devices, we first investigated the stability of a variety of electrodes for devices stored in an inert, dark environment. Second, a set of experiments was designed to separate the effects at the metal/organic interface from the degradation of the active layer or the hole extraction interface. To do this, Ca/Al electrodes were deposited to complete half of a substrate's devices, and samples were left both under constant illumination and 10% illumination (10% duty cycle of 1 sun illumination) in a glovebox environment. After more than 200 h of measurement, additional ...

UK PubMed Central (United Kingdom)

Background and ObjectivePulsed dye laser (PDL) treatment of cutaneous vascular lesions is associated with variable and unpredictable efficacy. Thus, alternative treatment...Full Text Available

International Nuclear Information System (INIS)

The fatigue life variability of the #alpha#+#beta# titanium alloy, Ti-6Al-2Sn-4Zr-6Mo increased with decreasing stress level. The variability in life was found to be due to segregation of lives due to two failure mechanisms. A bimodal cumulative distribution model was shown to accurately describe the combined failure modes. The nominal failure processes for the two regimes were similar, with crack nucleation occurring in equiaxed #alpha#p particles, irrespective of life or stress level. However the variability in life was not controlled by the size of the crack-nucleating #alpha#p, but rather by the ability of the material to distribute deformation and avoid early crack nucleation.

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... and operation of marine structures and to estimate coastal sediment transport. While the timely collection and report of high ... ...

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Brains are usually described as input/output systems: they transform sensory input into motor output. However, the motor output of brains (behavior) is notoriously variable, even under identical sensory...Full Text Available

CERN Document Server

In this paper we present a complete solution to the problem of multifractal analysis of multiple ergodic averages in the case of symbolic dynamics for functions of two variables depending on the first coordinate.

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Jul 25, 2011 ... Koji Mukai's Bibliography. Invited Reviews. Mukai, K. 1994, "ASCA PV Phase Observations of Cataclysmic Variables," in "New Horizon of X-ray ...

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Background and AimsAnnonaceae are one of the largest families of Magnoliales. This study investigates the comparative floral development of 15 species to understand the basis for...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

Knowledge on environmental variability and how it is affected by disturbances is crucial for understanding patterns of biodiversity and determining adequate conservation strategies. The aim of this study is to assess environmental variability in patches undergoing post-fire vegetation recovery, identifying trends of change and their relevant drivers. We particularly evaluate: the value of three spectral indices derived from Landsat satellite data [Normalized Burn Ratio (NBR), Normalized Difference Vegetation Index (NDVI) and Wetness Component of the Tasseled Cap Transformation (TCW)] for describing secondary succession; the effectiveness of three metrics (diversity, evenness and richness) as indicators of patch variability; and how thematic resolution can affect the perception of environme...

British Library Electronic Table of Contents (United Kingdom)

Climate variability greatly affects animals through direct and indirect effects. Animals with slow reproductive adaptation to ecological changes such as large mammals are likely to have evolved mechanisms to anticipate early such impacts of climate variability on the environment. One of the adaptive mechanisms between reproductive costs and benefits in mammals affects parental investment through biases in sex ratio. Deer might be likely to show an early detection of climate variability because conception takes place in early autumn, but the main raising cost in deer concerns lactation, which takes place at the end of the following spring. The aim of this paper is to assess whether there is a relationship between global indices of climate variability such as El Ni?o-Southern Oscillation (EN...

UK PubMed Central (United Kingdom)

The study of genetic variability within natural populations of pathogens may provide insight into their evolution and pathogenesis. We used a Mycobacterium tuberculosis high-density...Full Text Available

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measure meteorological variables and bulk water temper- ature. The locations of the buoys are given in Table 1. TB2 and TB3 were moved slightly farther south ...

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... Direct Search (SMOMADS) and Paciencia's NMADS [45] based on Kim and de Weck's ... Todd Paciencia for his foundational contributions. ...

British Library Electronic Table of Contents (United Kingdom)

In this paper we describe how cleavable surfactants decompose into water-insoluble silanols and two water-soluble products when subjected to vacuum plasma treatment. We used Raman spectroscopic analysis to confirm these structural changes, and we performed contact angle measurements and employed scanning electron microscopy to observe the surface morphologies of these compounds. Our contact angle measurements confirm that the products had degraded on nylon fabrics during argon gas plasma treatment. All of the PEG-silicone polyesters displayed excellent water-repellency; PEG6000-silicone exhibited the largest contact angle (130?) and, hence, the greatest water-repellency. Our results indicate that the silanols that form upon plasma treatment may be useful in coatings applications. We also f...

British Library Electronic Table of Contents (United Kingdom)

Tailor die quenching in the hot stamping of quenchable steel sheets was developed to produce ultra-high strength steel formed parts having strength distribution. Local portions of the heated sheet were quenched by holding grooved tools at the bottom dead centre during the stamping. Non-contact portions were generated in the sheet by grooving the tools, and thus the strength in the contact portions is high owing to the quenching and that in the non-contact portions is low owing to the lack of the quenching. Hat-shaped products having a tensile strength of approximately 1.5GPa only at four corners were formed.

International Nuclear Information System (INIS)

The newly discovered oxypnictide family of superconductors show very high critical temperatures of up to 55 K. Whilst there is growing evidence that suggests a nodal order parameter, point contact Andreev reflection spectroscopy can provide crucial information such as the gap value and possibly the number of energy gaps involved. For the oxygen deficient NdFeAsO_0_._8_5 with a T_c of 45.5 K, we show that there is clearly a gap value at 4.2 K that is of the order of 7 meV, consistent with previous studies on oxypnictides with lower T_c. In addition, taking the spectra as a function of gold tip contact pressure reveals important changes in the spectra which may be indicative of more complex physics underlying this structure. (rapid communication)

Energy Technology Data Exchange (ETDEWEB)

The oxidation of carbon black, CB, in presence of CeO{sub 2} is investigated to gain a better understanding of the effect of the contact between the two solids during this reaction. Different CB/CeO{sub 2} mixtures are tested in a fixed bed reactor. The experimental data are used to propose a model for CB oxidation in presence of CeO{sub 2}. It accounts for the size distribution of CeO{sub 2} particles, the contact area between CB and CeO{sub 2}, the mass of CB in the sample and the initial ratio CB/CeO{sub 2}. Corresponding kinetic parameters are determined. 35 refs., 10 figs., 3 tabs.

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Molecular dynamics simulations have been carried out of the radial distribution function of the hard sphere fluid for a range of densities in the equilibrium fluid and just into the metastable region. The first derivative of the hard-sphere radial distribution function at contact was computed and its density dependence fitted to a simple analytic form. Comparisons were made with semi-empirical formulae from the literature, and of these the formula proposed by Tao et al (1992 Phys. Rev. A 46 8007) was found to be in best agreement with the simulation data, although it slightly underestimates the derivative at the higher packing fractions in excess of about 0.45. Close to contact, within a few per cent of the particle diameter, the radial distribution function can be represented well by a second order polynomial. An exponential function, which has some useful analytic features, can also be applied in this region.

British Library Electronic Table of Contents (United Kingdom)

Heat transfer through the gas diffusion layer (GDL) is a key process in the design and operation of a PEM fuel cell. The analysis of this process requires the determination of the effective thermal conductivity as well as the thermal contact resistance between the GDL and adjacent surfaces/layers. The Part 1 companion paper describes an experimental procedure and a test bed devised to allow separation of the effective thermal conductivity and thermal contact resistance, and presents measurements under a range of static compressive loads. In practice, during operation of a fuel cell stack, the compressive load on the GDL changes. In the present study, experiments are performed on Toray carbon papers with 78% porosity and 5% PTFE under a cyclic compressive load. Results show a significant hy...

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Contact scanner system in Wolsung NPP(model ESE-1565) is early `70 equipment so most of components are obsolete. To make 100% compatible PCBs for this system is main object of the study. Most of components used in the system are now not available in the electric market, furthermore original system maker no longer supplies spare parts. System supplier(AECL) quoted lots of money than general PCBs prices in case of spare PCBs are re-marked by canada maker. Contents and scope of the study are specifications research and system analysis, improvements of repairability and reliability, circuit design and simulations using computer aided tools(CAE), make arbitrary mechanical contacts signal generator for test system. Now the long-run test of home made PCBs are conducting at Wolsung NPP. (author). 20 refs., 42 figs.

International Nuclear Information System (INIS)

The effects of focused-ion-beam-induced damage on electrical properties of n-type Si are investigated by Schottky contacts. Crystalline Si is exposed to 10-30 keV focused ion beam (FIB), followed by Pt deposition under vacuum of 4x10"-"4 Pa. From current-voltage-temperature measurements, barrier heights of the Schottky contacts are found to increase almost linearly as the FIB energy increases, with the maximum increment of 0.29 eV. The increase is suggested to be related to the arising of acceptorlike defects and an amorphous layer due to FIB damages. A theoretical model is set up to quantitatively describe the barrier height changes.

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LiNiO{sub 2} is one of the most promising material for positive electrodes of lithium-ion batteries. However, its behaviour during cycling and the existence of several phase transitions induced by the lithium ions de-intercalation process has not been explained so far. A transition electron microscopy study of various Li{sub x}NiO{sub 2} (0.25

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The initiation and characteristics of mossy zinc electrodeposits have been investigated. Batteries with zinc electrodes are candidates for electric vehicle applications; however, this electrode is prone to form non-compact deposits that contribute to capacity loss and battery failure. Moss is deposited when the current density is far from the limiting current. This morphology first appears only after the bulk deposit is approximately 1 {mu}m thick. In this investigation, the effects of flow rate (Re=0--4000), current density (0--50 mA/cm{sup 2}), concentration of the electroactive species (0.25 and 0.5 M), and the concentration of supporting electrolyte (3, 6, and 12 M) on the initiation of moss were examined. The rotating concentric cylinder electrode was employed for most of the experiments; and a flow channel was used to study the development of morphology. After the experiment, the deposit was characterized using ...

International Nuclear Information System (INIS)

Proton exchange membrane fuel cells (PEMFCs) are attractive because of their high conversion efficiency, low pollution, lightweight, and high power density. A major area of challenges is the design and engineering of active, robust, and low-cost electrocatalysts. This report discusses recent findings of our investigations of the design and nano-engineering of platinum-vanadium-iron catalysts for use in PEMFC. The membrane electrode assembly was prepared using nano-engineered PtVFe nanoparticles with controlled composition and size supported on carbon as cathode electrocatalysts. The electrocatalytic activity and stability of the catalysts have been characterized by both rotating disk electrode and membrane electrode assembly measurements. The trimetallic catalysts have been shown to exhibit excellent electrocatalytic performance in PEMFC in comparison with commercial platinum catalysts. The results exhibited a good ...

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Ferroelectric thin films such as BST, PZT and PLZT are extensively being studied for the fabrication of DRAMS since they have high dielectric constant. The large and reversible remnant polarization of these materials makes it attractive for nonvolatile ferroelectric RAM application. In this paper we report the characterization of Ba0.7Sr0.3TiO3 (BST) thin films grown by pulsed laser ablation on oxide electrodes. The structural and electrical properties of the fabricated devices were studied. Growth of crystalline BST films was observed on La0.5Sr0.5CoO3 (LSCO) thin film electrodes at relatively low substrate temperature compared to BST grown on PtSi substrates. Electrical characterization was carried out by fabricating PtSi/LSCO/BST/LSCO heterostructures. The leakage current of the heteros...

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Proof-of-principle experiments are reported for a new concept in electrically rechargeable zinc-air battery. The zinc electrode is a porous flow-thru type using a copper foam metal substrate with zinc deposition onto the foam metal from concentrated zincate electrolyte (as used in zinc-slurry type batteries). The bifunctional air electrode employs low-cost materials, being fabricated entirely from carbon-based precursors and small amounts of nickel and/or cobalt oxide. Corrosion measurements on the graphite materials in the air electrode indicate sufficient corrosion resistance for 8000 h life on charge. A prototype single cell was constructed having 1.5 Ah capacity producing 1.2 V discharge -2.0 charge at the three hour rate and has produced stable voltages for more than 150 cycles. Based on the 1.5 Ah prototype characteristics, design calculations for a 32 kWh battery project an energy density of about 110 Wh/kg, peak ...

International Nuclear Information System (INIS)

The nature of the electrolyte strongly influences the electrode kinetics of the oxygen evolution reaction (OER) and electrochemical ozone production (EOP) mainly by affecting the degree of coverage by the intermediates of both processes. The anomalous behaviour of the Tafel coefficient, b, as a function of temperature was attributed to surface adsorption of the electrolyte species, and the competition between them, as well as gas bubble adherence. Comparison of the current efficiencies of the EOP, PHI_E_O_P, determined for different temperatures and supporting electrolyte compositions, showed the presence of fluorinated anions increases PHI_E_O_P. The influence of the anion nature on PHI_E_O_P, when analysed in the light of the proposed electrode mechanism, reveals introduction into the electrolyte of anions having a high electronegativity changes the double layer structure resulting in an increase of surface concentration of the active centres ...

International Nuclear Information System (INIS)

In the present work, a rapid deposition anodic stripping voltammetry (ASV) for determination of uranium is presented. For this purpose, the uranyl hexacyanoferrate (K2UO2[Fe(CN)6]) is deposited electrochemically on a thin palladium-aluminum electrode (Pd-Al) from a UO22+ solution in the presence of K3Fe(CN)6. Then, the well stable (K2UO2[Fe(CN)6]) on the electrode was stripped by anodic differential pulse voltammetry for measuring the UO22+ ion concentration. The effect of operational parameters, including: concentration of K3Fe(CN)6, solution pH, deposition potential, and deposition time were studied. In optimum conditions, the calibration graph was linear in the concentration range 105-7 x 10-4 mol L-1 with a detection limit of 6.2 x 10-6 mol L-1. The influence of some concomitant ions in K2UO2[Fe(CN)6] formation was investigated. The proposed method was used for the rapid determination of uranium in some uranium mineral ores. (orig.)

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for? Learn the Issues Science & Technology Laws & Regulations About EPA Contact Us Water: Water Quality Criteria You are here: Water Science & Technology Surface Water Standards &...

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We have been developing an innovative Steam Generator concept of Fast Breeder Reactors by using liquid-liquid direct contact heat transfer. In this concept, the SG shell is filled with a molten alloys, which is heated by primary sodium. Water is fed into the high temperature molten alloy, and evaporates by direct contact heating. In order to obtain the fundamental information to discuss the heat transfer mechanisms of the direct contact between the water and the alloy, this phenomenon was visualized by real-time neutron radiography. JRR-3M real-time thermal neutron radiography in Japan Atomic Energy Research Institute was used. Followings are main results. (1) The vigorous evaporation occurs in the molten alloy. This phenomena is different from the known phenomenon such as the evaporation of refrigerant R-113 in the water. (2) The evaporation in the bubble has finished in a moment due to high heat transfer performance ...

UK PubMed Central (United Kingdom)

BackgroundActivation of the signal transducer and activator of transcription 3 (STAT3) within antigen presenting cells (APCs) is linked to abnormal APCs differentiation and function....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Indirect evaporative air coolers that use air-to-air plate-type heat exchangers show good promise (compared with compression air-conditioning systems) of extending the energy savings from arid, low-humidity areas to more widespread climatic conditions. However, no systematic experiment had been done concerning the effect of the wettability of aluminum plates on the effectiveness of the indirect evaporative cooling system. In this study, a testing apparatus was built where only one secondary channel and two primary channels were used so that different surfaces could be easily tested to determine the system`s effectiveness and the heat transfer coefficient. The advantage of this experimental apparatus is that plates of the heat exchanger can be easily changed in the test section instead of fabricating a complete heat exchanger for each test. A dynamic contact analyzer was used to quantitatively measure the wetting properties in terms of advancing and receding ...

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Jump to main content. [logo] US EPA Ozone Layer Protection - Alternatives / SNAP Recent Additions | Contact Us Search: All EPA This Area Go You are here: EPA Home Ozone Layer...

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In a process for separating insoluble red mud from Bayer process streams the improvement is described which comprises contacting and mixing a Bayer process stream with a tertiary polyamine having a molecular weight of at least about 10,000 in an amount effective to reduce the iron content thereof.

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Skip to Main Content Skip to Main Navigation National Highway Traffic Safety Administration Accessible menu--Sitemap Driving Safety Aggressive Driving Bicycles Child Safety...

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Bacterial processes in soil, including biodegradation, require contact between bacteria and substrates. Knowledge of the three-dimensional spatial distribution of bacteria at the microscale is necessary...Full Text Available

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... has rotated active duty battalions from its light infantry divisions. ... the departure should contact Major Jim Hinnant, 82nd Airborne Division PAO, at ...

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Laser assisted solar cell metallization processing which is a one step process is examined. The potential advantages of laser disposition techniques for photovoltaic systems are: a high resolution, no photolithography, clean and contamination free, in-situ sintering, and low contact resistance.

UK PubMed Central (United Kingdom)

Sensory experience plays a crucial role in regulating neuronal shape and in developing synaptic contacts during brain formation. These features are required for a neuron to receive, integrate, and transmit...Full Text Available

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NIST logo NIST Time NIST Home About NIST Contact Us A-Z Site Index Search Information Technology Laboratory About ITL What ITL does Organization ITL Functional Statement Standards...

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Survey - science for a changing world USGS Home Contact USGS Search USGS Hawaiian Volcano Observatory U.S. Geological Survey Open-File Reports 2007-1316 through 2007-1354...