bluuebunny/crossref_metadata_2025 huggingface dataset:
Alkali Doped Poly(vinyl alcohol) (PVA) for Anion-exchange Membrane Fuel Cells: Ionic Conductivity, Chemical Stability and FT-IR Characterizations
Authors: Fu Jing , Qiao Jinli , Lv Hong , Ma Jianxin , Yuan Xiao-Zi , Wang Haijiang
Published: February 2010

Novel alkaline solid polymer electrolyte membranes have been successfully prepared for poly(vinyl alcohol) (PVA), poly(vinyl alcohol)/poly(vinylpyrrolidone)(PVA/PVP) and poly(vinyl alcohol)/poly(ethylene glycol) dimethyl ether (PVA/PEGDE) by KOH doping. The ionic conductivity(σ) of the membranes was investigated as a function of cross-linking time, blending composition and water content. FT-IR spectroscopy was used for clarifying the conducting mechanism. In particular, the chemical stability of the membranes was investigated toward base treatment with elevated temperature at different KOH concentrations for potential fuel cell applications. The measured conductivity of the membrane ranged from 2.75 to 4.73×10−4 S cm-1 at room temperature for KOH doped PVA and, was greatly enhanced high up to 2 ×10-3 S cm-1 by addition of PVP and 1.5 ×10-3 S cm-1 by addition of PEGDE. The obtained membranes exhibited excellent chemical stability to high concentration base treatment (10M KOH) at elevated temperature of 120oC.
Ethanol Stripping in Alkaline Medium: A DEMS Study
Authors: Bayer Domnik , Cremers Carsten , Baltruschat Helmut , Tübke Jens
Published: February 2010

In this study, the adsorption of ethanol on platinum in alkaline medium is investigated by stripping voltammetry in combination with differential electrochemical mass spectrometry (DEMS). It is shown that the amount of adsorbed ethanol depends on the adsorption potential. Adsorbed ethanol can be oxidized to carbon dioxide in two different potential regions: one below 0.9 V vs. RHE and the other above 0.9 V vs. RHE. Furthermore, adsorbed ethanol can be reduced to methane below 0.2 V vs. RHE when the stripping voltammogram is started in cathodic direction from the adsorption potential. The number of electrons transferred per molecule of carbon dioxide evolved is calculated and found to be two in the potential region below 0.9 V vs. RHE, independent of the adsorption potential. A larger number of electrons is found in the potential region above 0.9 V vs. RHE. Based on the findings, a preliminary reaction scheme is presented.
Concentration Dependence of the Electro-Oxidation of Ethanol and Ethylene Glycol at Platinum in Alkaline Medium
Authors: Bayer Domnik , Berenger Sophie , Cremers Carsten , Tübke Jens
Published: February 2010

In the present work, the electro-oxidation of ethanol and ethylene glycol in alkaline medium is studied depending on their concentration by cyclic voltammetry, chronoamperometry and differential electrochemical mass spectrometry (DEMS). It is shown that in the case of ethanol, carbon dioxide as product of the oxidation can only be found during cyclic voltammetry. Within the investigated concentration range, potentiostatic experiments do not indicate bulk oxidation of ethanol to carbon dioxide. For ethylene glycol, the oxidation in cyclic voltammetry as well as in chronoamperometric experiments leads to significant carbon dioxide formation with the tendency that low concentrations and low potentials yield high carbon dioxide current efficiencies. Furthermore, comparatively higher current densities in cyclic voltammetry and chronoamperometric experiments indicate that with respect to ethanol, ethylene glycol is more active and the poisoning effect on platinum in alkaline medium is less severe.
Computer Model for T-x-y Diagram with a Binary Compound Decomposed at High Temperatures
Authors: Lutsyk Vasily , Zelenaya Anna
Published: February 2010

New technology of the T-x-y diagrams space models construction by the kinematical surfaces has been applied for the ternary systems without the solid solution. A diagram with the inner liquidus field of decomposing binary compound consists of five unruled and twelve ruled surfaces (with the horizontal position of forming segment) plus three horizontal invariant complexes and one vertical plane between the subsystems A-C-R and B-C-R. Three liquidus surfaces are built from the fragments. Computer model permits to use a phase diagram as an instrument to solve different applied tasks of heterogeneous design and physics-chemical analysis. For the given centre of masses it is possible to receive a vertical diagram of the material balance, and the isothermal state of arbitrary taken isopleth could be illustrated by the horizontal diagram of material balance.
Novel Nano- and Micro-Processing by Photoactivation of Methylene Iodide Precursor
Authors: Rashid Abdul , Landström Lars , Piglmayer Klaus
Published: February 2010

In this letter we present methylene iodide as a versatile precursor for nano- and microprocessing. It allows the deposition of Carbon micro/nano-fibers and nanotubes via chemical vapor deposition (CVD) using different metal catalysts (Pd, Ni, Fe, Co and Mn) on Si (100) substrates. Here, a versatile and low-cost IR lamp technique is employed to induce the deposition process. With this method carbon features could be obtained already at temperatures much lower than with common techniques. When utilizing 193nm excimer laser pulses, the precursor is activated to induce etching of Si and simultaneous deposition of carbon, at high local separation. The existence of thermally defined chemical boundaries suggests the possibility of high confinement and the formation etching/deposition structures of sub-micron sizes.
Effect of Deposition Time and Current Density on Kinetic Roughening of Electrodeposited Pt Thin Films
Authors: Nabiyouni Gholamreza
Published: February 2010

The effect of deposition time (film thickness) and deposition current density (growth rate) on the kinetic roughening of the films were studied using atomic force microscopy (AFM) and roughness calculation. Our films were electrodeposited on Au/Cr/ glass substrates, under galvanostatic control (constant current density), from a single electrolyte containing Pt4+ ions. The data is consistent with a rather complex behaviour known as "anomalous scaling" where both local and large scale roughnesses show power law dependence on the film thickness.
Influence of Particle Surface Potential on Electrocodeposition of BaSO4: A ζ-potential Study
Authors: Soccol Dimitri , Ntumba Ngoy Christian , Claessens Serge , Fransaer Jan
Published: February 2010

The influence of particle surface potential on the incorporation rate during electrocodeposition was studied. BaSO4 and K1.33Mn8O16 were used as model particles, as their surface potential could be controlled by potential determining ions that are electrochemically silent, Ba2+ and SO42− for BaSO4 and K+ for K1.33Mn8O16. It was shown by ζ-potential measurements in diluted electrolytes and metal plating baths that small additions of these ions sufficed to control the surface potential. Despite the electrochemical inactivity of these ions, current step measurements showed they had a marked influence on metal electrodeposition. However, for both particle types the correlation between ζ-potential and codeposition rate was much more pronounced than between electrochemical changes and codeposition rate. It was concluded that a less negative or more positive surface potential leads to an increase in codeposition. A model is proposed based on ion depletion between particle and electrode at close separation.
Electrochemically Formed Porous Silica as a Template for Metal Electrodeposition
Authors: Chazalviel Jean-Noël , Ozanam François
Published: February 2010

Mesoporous silica films can be obtained by high-potential anodic treatment of silicon in a dilute fluoride electrolyte. The electrochemical deposition of metals in this porous medium has been investigated. The electrochemical deposition of copper turns out to be difficult, which is probably due to the formation of a poorly adherent deposit. In contrast, nickel is deposited in the porous medium. The obtained structures exhibit enhanced SEM contrast, which allows for a direct confirmation of the stratified structure of porous silica previously inferred from X-ray reflectivity data. This stratified structure is clearly associated with the known oscillatory electrochemical behavior of silicon electrodes in fluoride electrolyte.
Double-Sided Mesoporous Silicon with Embedded Quasi-Regular Arranged Ferromagnetic Nanostructures Fabricated by Electrodeposition
Authors: Granitzer Petra , Rumpf Klemens , Albu Mihaela , Pölt Peter
Published: February 2010

Porous silicon matrices fabricated by wet etching are used as template for the deposition of metal nanostructures. The anodization of the silicon wafer is performed on one or on both sides in employing a double-tank electrolytic cell. The resulting porous layers are subsequently filled with a ferromagnetic metal by electrodeposition. In case of double-sided samples an alternating pulsed current is applied. These two processes are extended to ultrathin samples with an entire thickness of about 60 µm. The morphology of the porous structure exhibits average pore-diameters of 60 nm, a mean pore-spacing of 45 nm and a pore-length of 40 µm. Ferromagnetic metals are electrochemically deposited as nanostructures with a specific distribution within the pores.
Cell Uptake of Nanoparticles
Authors: Xu Hengyi , Aguilar Zoraida P. , Wei Hua , Wang Andrew
Published: February 2010

Nanotechnology, the area of study involving nanoparticles, century; medical fields. The nanotechnology is one of the fastest growing sectors of the high-tech economy in the 21st industry, it is currently undergoing unprecedented development in nowadays especially in areas of biological research for clinical, environmental and life science applications. The most frequently used nanoparticles are superparamagnetic iron oxide (SPIO) nanoparticles and semiconductor quantum dots (QDs). SPIO nanoparticles with nanometer sizes and superparamagnetic properties are widely used for labeling and sorting cells or organelles, magnetic resonance imaging, targeted drug delivery, and hyperthermia. QDs combined the unique size-dependent physical properties, excellent chemical and photochemical stability, controlled and increased endocytosis, enhanced cooperative binding activity, and easy introduction of multi-functionality for targeted delivery and imaging, and became the most promising labeling tool for life science studies. Both types of nanomaterials provide special approaches for complex studies and play very important roles in modern biomedical research. However, non-specific uptake of QDs and SPIO nanoparticles is a major concern because it can lead to false positives or false results. Hence, we report cellular uptake studies on SPIO nanoparticles and QDs conducted on breast cancer cell line SK-BR3. The results show that both QDs and SPIO nanoparticles have very strong non-specific cellular uptake. With specially designed blocking buffer (BBB) the non-specific signals were significantly decreased.
Absorption of Water and Corrosion Performance of a Clear and Pigmented Epoxy Coating on Al-2024 Alloy
Authors: Foyet Adolphe , Wu Te Hui , Kodentsov A. , Van der Ven Leo G. , De With Gijsbertus , Van Benthem Rolf A.
Published: February 2010

The corrosion performance of Al-2024 substrates coated with an epoxy clear coating and a pigmented epoxy coating was investigated. The absorption of water in the pigmented coating was high compared to the clear coating. The clear coating provided a good barrier which is stable beyond 120 days of immersion in a 0.5 M NaCl solution. The shape of the Nyquist plot of the pigmented coating changed with immersion time and reveals the existence of physico-chemical processes in the coating and/or at the interface. Its impedance magnitude at low frequencies remained very high (~ 109 Ω.cm2) after 72 days of immersion in sodium chloride solution. Both coatings exhibited good dry adhesion on Al-2024. The wet adhesion of the clear coating was poor while the stress (~ 9 MPa) required in a pull off adhesion test of the wet pigmented coating remained high.
Analysis Of Corrosion Products Formed By Edge Corrosion Of Residual Coated Steel Sheets
Authors: Tahara Akira , Shinohara Tadashi
Published: February 2010

The object of this study is to clarify the mechanism and difference of edge corrosion behaviors of prepainted Zn and 55%-Zn coated steels, from the EPMA analysis of corrosion products of prepainted metallic coated steels. Cross section of two kinds (Zn and 55%Al-Zn coating) of prepainted metallic coated steel sheets exposed in Miyako-jima (Subtropical marine area) and Choshi (Moderate marine) are analyzed. Samples for cross section analysis were prepared by a new technique using Ar ion etching. Corrosion of both samples started at the edge of metal coating layer, and proceeded to inner area gradually. In the case of corrosion of Zn coating layer, corrosion progresses almost uniformly from the edge. In the case of corrosion of 55%Al-Zn coating layer, the tendency with which the Zn-rich part of the eutectic phase corrodes selectively.
Wet/Dry Cycle Corrosion Behavior of Model Cut-Edge Formed on Pre-Painted Zinc Alloy Coated Steels by Laser Fabrication
Authors: Sakairi Masatoshi , Kageyama Akihiro , Kikuchi Tatsuya
Published: February 2010

Laser machining technique, which used focusing pulse YAG laser beam irradiation, was applied to form area ratio of controlled model cut-edge on pre-painted zinc related coated steels. A corrosion behavior of formed model cut-edge was investigated by wet/dry cyclic corrosion test using 10 mol m-3 NaCl solutions in 80 % R.H. atmosphere. In high area ratio zinc specimens, red rust is observed on steel substrate at model cut-edge. The chromate inhibits corrosion of formed model cut-edge on pre-painted zinc coated steels. The behavior of corrosion penetration under the paint depends on composition of coating. In the case of painted zinc-55 mass% aluminum coated steel, zinc rich phase preferentially dissolved. The preferential zinc rich layer dissolution and corrosion products formation cause paint peel off.
The Effect Of Humidity On Titanium Dioxide Photocatalysed PVC Degradation
Authors: Cashmore Samantha , Robinson Andrew , Worsley David
Published: February 2010

Most organic coatings are pigmented with Titanium Dioxide (TiO2) to increase their covering power. TiO2 can be photoactivated under UV irradiation causing the formation of free radicals leading to accelerated degradation of the polymeric coating and release of Carbon Dioxide (CO2). An important consideration is the role of relative humidity (RH) of the atmosphere contacting the irradiated panels. This has been studied for pigmented UPVC films using a novel closed-loop flat panel irradiation reactor and measuring the CO2 evolution kinetics by FTIR spectroscopy. The atmospheric humidity has been controlled (RH 0% to 98%) in the flow system using saturated salt solutions and the work has shown that the peak in degradation rate occurs at RH of 32% which coincides with a peak in photo-generated hydrochloric acid concentration. PVC films can be stabilised by incorporating hydrotalcite mineral pigments (2-10%) which replace hydrochloric acid with carbonic acid and deactivate the TiO2.
Electrodeposition of Alloys of Rhenium with Iron-Group Metals from Aqueous Solutions
Authors: Naor Adi , Eliaz Noam , Gileadi Eliezer
Published: February 2010

Rhenium (Re) is a refractory metal, which exhibits unique combination of properties, making it an attractive material in a variety of applications. The mechanism of Re electrodeposition is still unknown. However, there are clear indications that codeposition of alloys with iron-group metals may lead to higher-quality coatings and higher Faradaic efficiencies (FE's). Re-Me alloys, where Me=Ni, Fe or Co, were deposited galvanostatically. The bath solution consisted of ammonium perrhenate, nickel or cobalt sulfamate or iron sulfate, citric acid, and magnesium sulfamate. The effects of bath chemistry and deposition time on the FE, Re content and partial deposition currents were determined. Rhenium contents as high as 93 at.% and FE values as high as 96% were attained. The results are discussed with emphasis on routes to increase the FE and Re content in the coating. The possible role of the 2nd metal in electrodeposition of Re is presented.
Electrochemical Impedance Characterization of Ultra-Thin Carbon Overcoats
Authors: Kobsiriphat Worawarit , Supadee Laddawan , Siangchaew Krisda
Published: February 2010

Ultra-thin carbon overcoats deposited on Al2O3-TiC (AlTiC) substrates were characterized using electrochemical impedance spectroscopy. By depositing diamond-like carbon (DLC) directly on AlTiC, the polarization resistance increased to 10^7 ohm-cm2 from ~10^5 ohm-cm2 for bare AlTiC. Two adhesion layer materials were studied: Si and Si3N4. The polarization resistance of DLC/Si3N4 films was 100 times higher than that of DLC/Si. The impedance, wear and magnetic test results indicated that Si3N4 is a more suitable seed material. Comparing films with the same DLC thickness, the Si3N4 layer thickness showed no influence on the resistance. For the same Si3N4 thickness, a thicker DLC layer yielded slightly higher pore resistance. This study reveals that the thinner carbon overcoats (DLC/Si3N4 thickness = 8/12 or 12/8 Aå) provided equal, if not better, corrosion protection than the thicker films. The advantage of a thinner carbon overcoat is that it facilitates an improvement in sensitivity of the magnetic sensor.
Electrochemical Characteristics of Titanium Carbide Derived Carbon|1-Ethyl-3-Methylimidazolium Tetrafluoroborate Electrical Double Layer Capacitors
Authors: Kurig Heisi , Romann Tavo , Jänes Alar , Lust Enn
Published: February 2010

Symmetric two electrode supercapacitors were assembled in pure argon atmosphere (99,9999%) using titanium carbide derived carbon (C(TiC)) electrodes, TF4425 separator (from Nippon Kodoshi) and room temperature ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF4) as an electrolyte. Cyclic voltammetry, electrochemical impedance and constant current charging/discharging data were used to describe the capacitive behavior of system studied in the temperature region from 25 to 80 °C. The limits of ideal polarizability, low-frequency limiting capacitance, time constant, time stability, and other characteristics have been calculated and discussed. Comparatively high gravimetric energy (40 Wh kg-1) and power (130 kW kg-1) per active C(TiC) weight have been calculated, weakly depending on temperature, if T {less than or equal to} 59 ºC. Results obtained have been compared with results for supercapacitors based on 1 M (C2H5)3CH3NBF4 in acetonitrile.
A Molecular Dynamics Study of the Effect of Incident Angle on Dissociation Probability of H2/D2 - Pt(111) System
Authors: Koido Tetsuya , Ito Daigo , Tokumasu Takashi , Tomarikawa Kou , Yonemura Shigeru
Published: February 2010

The effect of incident angle on dissociation probability is analyzed by Molecular Dynamics (MD) method. Hydrogen is used as the gas molecule and Pt(111) is used as the surface. The embedded atom method (EAM) is used as the interaction potential between the gas molecule and the Pt(111) surface. Initially, the effect of motion of atoms or molecules (dynamic effects) on dissociation probability is discussed. It shows that dynamic effects on the dissociation phenomena are very large at top site. MD simulations of D2 molecules impinging on a Pt(111) surface are also carried out, changing the incident angle and its effects are analyzed. The results are also compared to those obtained by the molecular beam experiments to check the validity of the simulations. Consequently the results show that the dependence of translational energy and incident angle on dissociation probability roughly agree to those of experiments.
Performance of a Printable Enzymatic Fuel Cell: Study on Mediated ThL Laccase Cathode
Authors: Tuurala Saara , Smolander Maria , Uotila Johanna , Kaukoniemi Otto-Ville , Boer Harry , Valkiainen Matti , Vaari Anu , Koivula Anu , Jenkins Peter
Published: February 2010

In this work the performance of a printed ThL laccase biocathode is studied utilizing different electrode substrates, compositions and enzyme activities. The results indicate that the performance of the manufactured biocathode can be optimized by selecting a suitable substrate material and increasing the enzyme and mediator loading. By varying the substrate material app. 40 % increase in the cell performance was achieved. In addition by adding ten times higher amount of enzyme and mediator increased the cell performance app. 20 %.
Electrosynthesis Thermodynamic Study of the Poly (o-methoxyaniline) POMA
Authors: Pinto Simone S. , Moura Andreza , Gonçalves Joseane Mercia da Rocha P , Gonçalves Emerson , Rezende Mirabel Cerqueira
Published: February 2010

Over the past 15 years, conducting polymers have been studied as additives with excellent potential for application in the processing of materials used in the areas of electromagnetic interference and microwave absorption, Members of this new class of materials called "synthetic metals", have one thing in common: long systems p conjugates, ie, shifting single and double bonds along the chain. The obvious interest is to combine in a single material the electrical properties of a semiconductor or metal with the advantages of a polymer. Poly-methoxianilyne, POMA is a group of derivatives of polyaniline obtained by the polymerization of aniline sulfonic. In these work we studied via electrochemical synthesis the thermodynamic parameters of polymerization reaction of POMA, the polymer obtained was characterized via Raman, DSC and UV-vis. The thermodynamic parameters involved in the electropolymerization as Gibbs free energy, entropy and equilibrium constant were determined
Prediction of Cell Voltage and Chlorine Current Efficiency of Aqueous HCl Electrolysis Utilizing an Oxygen Reducing Cathode Based on Artificial Neural Network
Authors: Ashrafizadeh Seyed Nezamedin , Mohammadi Fereydoon , Sattari Abolfazl , Shojaikaveh Narjes
Published: February 2010

The effects of different process parameters on the cell voltage and chlorine current efficiency (ChCE) of the HCl membrane electrolysis were thoroughly studied and artificial neural network (ANN) models were developed for the prediction of them. A Half-MEA oxygen reducing membrane electrolysis cell with a projected area of 10 cm2 employing a dimensionally stable anode (DSA®) was employed to study the process. The cell voltage was increased with current density while this relation occurred in an opposite direction for other process parameters meanwhile the ChCE was decreased with current density and increased with other process parameters. 40 data (75%) and 13 data (25%) of total 53 distinct experiments were used to train and test the networks respectively. The predicted cell voltages and ChCEs using ANN modeling were found to be very close to the measured values with an average deviation of about 3.45% & 7.18% for test validation data, respectively.
Nano-Architecture on the Mud-Cracked Surface of IrO2-Ta2O5 Binary System
Authors: Kawaguchi Kenji , Haarberg Geir Martin , Morimitsu Masatsugu
Published: February 2010

Catalytic coatings comprising a mixture of IrO2 and Ta2O5 were prepared at 50-80 mol% Ir by thermal decomposition at 470 oC, and the crystallographic structures and surface morphologies were investigated. XRD analysis and high-resolution SEM observation using low accelerated incident beam revealed that decreasing Ir ratio made a phase transition of IrO2 from crystalline to partly amorphous, and nano IrO2 particles of 10 nm or less and nano chains made of them, which were uniformly dispersed on the flat area of the coating, were generated at 50-60 mol% Ir.
Improvement of Electrical and Thermoelectric Properties of MOCVD-Grown InSb Thin Films Using Si-Doped Interfacial Layer
Authors: Nagata Hirotaka , Homma Hideyuki , Yamaguchi Shigeo
Published: February 2010

We characterized the electrical and thermoelectric properties of Si-doped InSb thin films into the interface. Their electrical properties were measured in the temperature range from 100K to 600K. The values of Hall mobility at room temperature were 11300cm2/Vs, 18800cm2/Vs, 17600cm2/Vs and 20100cm2/Vs for 0nm, 3nm, 170nm, and 500nm-thick Si-doped InSb layer, respectively. The value of mobility increased using Si-doping. This result shows that the electrical and thermoelectric properties were improved by Si doping into the interface. Therefore, Si doping makes a good effect on the interface between InSb layer and InAsSb buffer layer, resulting from that defects in the InSb layer near the interface decreased by Si doping.
Redox Properties of Ni-YSZ Anodes
Authors: Zhang Yun , Liu Bin , Tu Baofeng , Dong Yonglai , Cheng Mojie
Published: February 2010

The NiO-YSZ composites with 30wt%, 50wt.% and 70wt.% NiO were investigated by the temperature programmed reduction (TPR), scanning electron microscope (SEM) and dilatometer (DIL) methods. The NiO in the sintered sample with higher content of NiO shows highest activity towards reduction. After re-oxidation at 800oC, the main reduction peak temperature is not clearly dependent on the NiO content, the higher temperature can accelerate the aggregation of NiO more obviously and make the formed NiO particles have lower activity during re-oxidation. The thermal expansion coffient increases with the increasing of NiO content, which is due to the higher TEC of NiO and the high contribution of NiO to the framework of composite.
Preparation of Poly(3,4-ethylenedioxythiophene) Films on Piezoelectric Quartz Crystal and their Gas Sensitivities
Authors: Pasquini Irene , Foresti Maria Luisa , Innocenti Massimo , Fort Ada , Mugnaini Marco , Pigani Laura , Vignoli Valerio , Rocchi Santina , Loglio Francesca
Published: February 2010

This paper describes the development and the results of a Quartz Crystal Microbalance (QCM) sensor for NO2 detection with the sensitive layer made of a thin film of poly (3,4-ethylenedioxythiophene) PEDOT. The PEDOT was obtained by electropolymerization on one of the gold electrodes of a 10 MHz AT-cut commercial quartz crystal. The sensor performance in terms of sensitivity and selectivity were assessed exploiting an ad hoc chemical sampling unit, and a low noise conditioning and processing electronic system. The preliminary obtained results show a NO2 resolution and sensitivity of the order of 1 ppm, and 2.6 Hz/ppm, respectively, at 35°C constant room temperature and 0% relative humidity, and show that a satisfactory repeatability can be achieved with recovery cycles in N2 at room temperature.
Detection of Degradation of Lithium-Ion Batteries with Acoustic Emission Technique
Authors: Komagata Shogo , Kuwata Naoaki , Baskaran Rangasamy , Kawamura Junichi , Sato Kazuhisa , Mizusaki Junichiro
Published: February 2010

Acoustic Emission (AE) technique is employed to detect degradation events inside of lithium-ion batteries. A commercial 18650 type battery and a model half cell (Li/organic electrolyte /LiCoO2) are monitored with AE technique during charge and discharge cycles. In the commercial battery, AE events are detected during every discharge process at SOC of around 35% and 15%. These AE can be attributed to the fracture of cathode material by phase transition. In the model half cell, AE events are found early cycles in charge process owing to the SEI formation, however in discharge process detected only under high C rate.
Low-Field NMR-Electrochemical Cell For In Situ Measurements of Paramagnetic Species
Authors: Barbosa Lúcio L. , Colnago Luiz A. , Carlos Ivani , M. S. Nunes Luiza
Published: February 2010

The main advantage of in situ measurements which couple electrochemistry techniques (EC) and nuclear magnetic resonance spectroscopy (NMR) is an increase in sensitivity and precision in the qualitative and quantitative analysis of the organic compounds. The present paper describes the development of a simple and practical spectroelectrochemical cell and presents the first use of low-field NMR spectroscopy coupled with electrochemistry to determine (in real time, during electrolysis) the change in the copper-sorbitol complex concentration, [Cu(sorb)2]2-. The electrolysis was realized at constant potential, and NMR measurements were performed by Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence. The CPMG results showed that the T2 measurements are influenced by the concentration of the paramagnetic ion, copper. The T2 value variation caused by the electrochemistry reaction at E = -1.15 V of complex allowed determining in real time the quantity of species consumed, which was approximately 10% of [Cu(sorb)2]2- initial concentration. The enhanced performance provided by in situ EC-NMR demonstrates its great promise for the quantitative determination of single species or complexes.
Effect of Absorbed Hydrogen on Microstructure of Electrodeposited Cobalt
Authors: Nakayama Akira , Fukumuro Naoki , Yae Shinji , Matsuda Hitoshi
Published: February 2010

The objective of this study is to elucidate the relationship between the total amount of hydrogen absorbed in electrodeposited cobalt films and their microstructure. The electrodeposited cobalt films were produced by such different depositing conditions as a solution pH, bath temperature, and current density. Structure analysis with XRD and TEM and hydrogen analysis with TDS reveal that the cobalt films with higher absorbed hydrogen content have a structure with coarse grain that consisted of hcp(100) preferred orientation. On the other hand, the cobalt films with lower absorbed hydrogen content have a stacking fault structure of hcp(110)/fcc(220). The total amount of absorbed hydrogen has a liner relationship with the stacking fault ratio and the grain size.
Evaluation of Data Quality and Drought Monitoring Capability of FY-3A MERSI Data
Authors: Xiang Daxiang , Liu Liangming , Wang Qiao , Yang Na , Han Tao
Published: February 2010

FY-3A is the second Chinese Polar Orbital Meteorological Satellite with global, three-dimensional, quantitative, and multispectral capabilities. Its missions include monitoring global disasters and environment changes. This study describes some basic parameters and major technical indicators of the FY-3A and evaluates data quality and drought monitoring capability of the Medium-Resolution Imager (MERSI) onboard the FY-3A. Data obtained with the MERSI was compared with that of the MODerate-resolution Imaging Spectroradiometer (MODIS), imaged at the same time period and geographic zone. In addition, the Temperature/Vegetation Drought Index (TVDI), a highly accurate and stable monitoring model, was used to monitor drought condition with MERSI and MODIS sensors. It is found in the study that the relative accuracy of data, obtained with these two devices, was consistent with the acceptable overall accuracy of 93.8. Furthermore, spatial resolution of MERSI is superior as compared to that of MODIS. Therefore, FY-3A MERSI can serve a reliable and new data source for drought monitoring.
Improving Farmers’ Perception and Use of Climate Predictions in Farming Decisions: A Transition Model
Authors: PytlikZillig Lisa M. , Hu Qi , Hubbard Kenneth G. , Lynne Gary D. , Bruning Roger H.
Published: February 2010

Despite tremendous efforts to improve weather and climate predictions and to inform farmers about the use of such weather products, farmers’ attitudes toward forecast use remain poor and farmer use of forecasts has not increased. This paper describes features of a new conceptual model for facilitating farmers’ use of weather products and offers preliminary evidence for its effectiveness based on a test-of-concept prototype. The prototype system provides farmers with contextualized information, the opportunity to use that information in relevant farming contexts, and collaborative interaction with other users. In addition, scaffolding and feedback are incorporated in the model to enhance learning and motivation. Surveys before and after use of the prototype system, and focus-group discussion after system use, were conducted to obtain evaluations from 15 farmers in southeastern Nebraska. Farmers’ evaluations of the system were moderately positive and indicated greater intentions to use the products in the future than they had in the past. However, farmers only slightly increased their positive expectancies of various general categories of weather and climate products, supporting the difficulties associated with changing overall attitudes when attempting to transfer scientific improvements into practical uses. It is suggested that multiple exposures to such a system and more individualized and personally relevant use opportunities may further enhance the power of the proposed model.
Barotropic and Baroclinic M2 Tides in the Monterey Bay Region
Authors: Carter G. S.
Published: February 2010

A high-resolution (250 m) primitive equation model is used to simulate the depth-averaged and baroclinic M2 tides in the Monterey Bay region. The model shows a high level of skill in comparisons with sea level observations. ADCP current observations within the submarine canyon are reasonably well reproduced. The modeled depth-averaged currents have a complex spatial pattern with magnitudes in excess of 0.1 m s−1 near Moss Landing. During the second half of flood (ebb) tide, the flow is into (out of) the bay through the canyon but out of (into) the bay over the shelf regions. This depth-averaged flow pattern is not evident in a diagnostic run, implying a feedback between the internal tides and the pressure gradient in the bay. The depth-integrated baroclinic (total minus depth-averaged) energy fluxes show a complex beamlike pattern due to the interaction of energy from multiple sources. The beams have magnitudes up to 1 kW m−1 interspersed with regions of near-zero depth-integrated flux. Energy entering the bay propagates northward from generation regions along the continental margins to the south of the bay (notably on the flanks of Sur Platform) and is steered into the canyon. A localized increase in depth-integrated baroclinic flux magnitude (up to 5 times the values elsewhere in the domain) closely follows the canyon axis near the mouth of the bay, presumably due to topographic focusing. Upper ocean velocities from a long-term surface mooring (MBARI M1) are used to assess the temporal variability of the M2 tide outside the canyon.
Costs and outcomes associated with an aripiprazole add-on or switching open-label study in psychosis
Authors: Aitchison Katherine J , Mir Amna , Shivakumar Kuppuswami , McAllister Victoria DM , O’Keane Veronica , McCrone Paul
Published: February 2010

Health service providers increasingly need to consider not only the efficacy and safety of a therapy, but also its cost. Our hypothesis was that in our previously reported aripiprazole add-on or switching study, the improved outcomes would be associated with reduced costs. We here report data from this study, now to 52-week follow-up, with 27 total recruits (outpatients partially refractory or intolerant of their current antipsychotic regime). Serial clinical ratings included the Quality of Life Scale and Client Service Receipt Inventory, applied at baseline ( N = 24), week 26 ( N = 21) and 52 ( N = 18). Cost data were unavailable for the drop outs. On last observation carried forward (LOCF) analysis, there was a significant increase in the Quality of Life Scale between baseline and one year ( p = 0.007). There were also reductions over time in total direct and indirect costs. For study completers, the total costs at the one-year follow-up period were £482 less than those for the corresponding baseline period, with the Quality of Life Scale score at one year being 21.6 points (or 16.4 on LOCF analysis) higher. Therefore, in the completers, improved outcome was associated with reduced costs. Cost-effectiveness could be similarly investigated in a controlled trial.
G-CSF protects motoneurons against axotomy-induced apoptotic death in neonatal mice
Authors: Henriques Alexandre , Pitzer Claudia , Dupuis Luc , Schneider Armin
Published: February 2010

Background

Granulocyte colony stimulating factor (G-CSF) is a growth factor essential for generation of neutrophilic granulocytes. Apart from this hematopoietic function, we have recently uncovered potent neuroprotective and regenerative properties of G-CSF in the central nervous system (CNS). The G-CSF receptor and G-CSF itself are expressed in α motoneurons, G-CSF protects motoneurons, and improves outcome in the SOD1(G93A) transgenic mouse model for amyotrophic lateral sclerosis (ALS). In vitro, G-CSF acts anti-apoptotically on motoneuronal cells. Due to the pleiotrophic effects of G-CSF and the complexity of the SOD1 transgenic ALS models it was however not possible to clearly distinguish between directly mediated anti-apoptotic and indirectly protective effects on motoneurons. Here we studied whether G-CSF is able to protect motoneurons from purely apoptotic cell death induced by a monocausal paradigm, neonatal sciatic nerve axotomy.

Results

We performed sciatic nerve axotomy in neonatal mice overexpressing G-CSF in the CNS and found that G-CSF transgenic mice displayed significantly higher numbers of surviving lumbar motoneurons 4 days following axotomy than their littermate controls. Also, surviving motoneurons in G-CSF overexpressing animals were larger, suggesting additional trophic effects of this growth factor.

Conclusions

In this model of pure apoptotic cell death the protective effects of G-CSF indicate direct actions of G-CSF on motoneurons in vivo. This shows that G-CSF exerts potent anti-apoptotic activities towards motoneurons in vivo and suggests that the protection offered by G-CSF in ALS mouse models is due to its direct neuroprotective activity.
Predictive ability of an early diagnostic guess in patients presenting with chest pain; a longitudinal descriptive study
Authors: Verdon François , Junod Michel , Herzig Lilli , Vaucher Paul , Burnand Bernard , Bischoff Thomas , Pécoud Alain , Favrat Bernard
Published: February 2010

Background

The intuitive early diagnostic guess could play an important role in reaching a final diagnosis. However, no study to date has attempted to quantify the importance of general practitioners' (GPs) ability to correctly appraise the origin of chest pain within the first minutes of an encounter.

Methods

The validation study was nested in a multicentre cohort study with a one year follow-up and included 626 successive patients who presented with chest pain and were attended by 58 GPs in Western Switzerland. The early diagnostic guess was assessed prior to a patient's history being taken by a GP and was then compared to a diagnosis of chest pain observed over the next year.

Results

Using summary measures clustered at the GP's level, the early diagnostic guess was confirmed by further investigation in 51.0% (CI 95%; 49.4% to 52.5%) of patients presenting with chest pain. The early diagnostic guess was more accurate in patients with a life threatening illness (65.4%; CI 95% 64.5% to 66.3%) and in patients who did not feel anxious (62.9%; CI 95% 62.5% to 63.3%). The predictive abilities of an early diagnostic guess were consistent among GPs.

Conclusions

The GPs early diagnostic guess was correct in one out of two patients presenting with chest pain. The probability of a correct guess was higher in patients with a life-threatening illness and in patients not feeling anxious about their pain.
NAD+ metabolite levels as a function of vitamins and calorie restriction: evidence for different mechanisms of longevity
Authors: Evans Charles , Bogan Katrina L , Song Peng , Burant Charles F , Kennedy Robert T , Brenner Charles
Published: February 2010

Background

NAD+ is a coenzyme for hydride transfer enzymes and a substrate for sirtuins and other NAD+-dependent ADPribose transfer enzymes. In wild-type Saccharomyces cerevisiae, calorie restriction accomplished by glucose limitation extends replicative lifespan in a manner that depends on Sir2 and the NAD+ salvage enzymes, nicotinic acid phosphoribosyl transferase and nicotinamidase. Though alterations in the NAD+ to nicotinamide ratio and the NAD+ to NADH ratio are anticipated by models to account for the effects of calorie restriction, the nature of a putative change in NAD+ metabolism requires analytical definition and quantification of the key metabolites.

Results

Hydrophilic interaction chromatography followed by tandem electrospray mass spectrometry were used to identify the 12 compounds that constitute the core NAD+ metabolome and 6 related nucleosides and nucleotides. Whereas yeast extract and nicotinic acid increase net NAD+ synthesis in a manner that can account for extended lifespan, glucose restriction does not alter NAD+ or nicotinamide levels in ways that would increase Sir2 activity.

Conclusions

The results constrain the possible mechanisms by which calorie restriction may regulate Sir2 and suggest that provision of vitamins and calorie restriction extend lifespan by different mechanisms.
Genetic variation in the adiponectin receptor 2 (ADIPOR2) gene is associated with coronary artery disease and increased ADIPOR2 expression in peripheral monocytes
Authors: Halvatsiotis Iosif , Tsiotra Panayoula C , Ikonomidis Ignatios , Kollias Anastasios , Mitrou Panagiota , Maratou Eirini , Boutati Eleni , Lekakis John , Dimitriadis George , Economopoulos Theofanis , Kremastinos Dimitrios T , Raptis Sotirios A
Published: February 2010

Background

Adiponectin is an adipose tissue secreted protein known for its insulin sensitising and anti-atherogenic actions. To this date two adiponectin receptors have been discovered, adiponectin receptor 1 (ADIPOR1) and adiponectin receptor 2 (ADIPOR2). The aim of this study was to investigate the association of ADIPOR2 gene variations with coronary artery disease (CAD).

Methods

Eight common single nucleotide polymorphisms (SNPs) spanning the entire ADIPOR2 locus were chosen to perform association studies with anthropometric and metabolic parameters in a Greek population. They were classified as either CAD (stenosis >50% in at least one main vessel) or non-CAD individuals in accordance with coronary angiography data.

Genotyping was performed using a microsphere-based suspension array and the Allele Specific Primer Extension (ASPE) method. Expression of ADIPOR2 protein and mRNA in circulating CD14+ monocytes were determined using flow cytometry and real time Polymerase Chain Reaction assays respectively.

Results

There was a significant difference in the distribution of genotypes of polymorphism rs767870 of ADIPOR2 between CAD and non-CAD individuals (p = 0.017). Furthermore, heterozygotes of the rs767870 polymorphism had significantly lower Flow Mediated Dilatation (FMD) values, higher values of Intima-Media Thickness (IMT) and increased ADIPOR2 protein levels in peripheral monocytes, compared to homozygotes of the minor allele after adjustment for age, sex, waist to hip ratio and HOMA.

Conclusions

Our findings suggest that variants of ADIPOR2 could be a determinant for atherosclerosis independent of insulin resistance status, possibly by affecting ADIPOR2 protein levels.
Risk Factors for Prostate Cancer Detection After a Negative Biopsy: A Novel Multivariable Longitudinal Approach
Authors: Gann Peter H. , Fought Angela , Deaton Ryan , Catalona William J. , Vonesh Edward
Published: February 2010

Purpose

To introduce a novel approach for the time-dependent quantification of risk factors for prostate cancer (PCa) detection after an initial negative biopsy.

Patients and Methods

Data for 1,871 men with initial negative biopsies and at least one follow-up biopsy were available. Piecewise exponential regression models were developed to quantify hazard ratios (HRs) and define cumulative incidence curves for PCa detection for subgroups with specific patterns of risk factors over time. Factors evaluated included age, race, serum prostate-specific antigen (PSA) concentration, PSA slope, digital rectal examination, dysplastic glands or prostatitis on biopsy, ultrasound gland volume, urinary symptoms, and number of negative biopsies.

Results

Four hundred sixty-five men had PCa detected, after a mean follow-up time of 2.8 years. All of the factors were independent predictors of PCa detection except for PSA slope, as a result of its correlation with time-dependent PSA level, and race. PSA (HR = 3.90 for > 10 v 2.5 to 3.9 ng/mL), high-grade prostatic intraepithelial neoplasia/atypical glands (HR = 2.97), gland volume (HR = 0.39 for > 50 v < 25 mL), and number of repeat biopsies (HR = 0.36 for two v zero repeat biopsies) were the strongest predictors. Men with high-risk versus low-risk event histories had a 20-fold difference in PCa detection over 5 years.

Conclusion

Piecewise exponential models provide an approach to longitudinal analysis of PCa risk that allows clinicians to see the interplay of risk factors as they unfold over time for individual patients. With these models, it is possible to identify distinct subpopulations with dramatically different needs for monitoring and repeat biopsy.
Induction of Endothelin-2 Expression by Luteinizing Hormone and Hypoxia: Possible Role in Bovine Corpus Luteum Formation
Authors: Klipper Eyal , Levit Anat , Mastich Yonit , Berisha Bajram , Schams Dieter , Meidan Rina
Published: February 2010

The pattern and regulation of endothlin-2 (EDN2) expression and its putative roles in bovine ovaries were investigated. EDN2 mRNA was determined in corpus luteum (CL) and during folliculoluteal transition induced by GnRH in vivo. EDN2 was elevated only in the early CL and was not present in older CL. In the young CL, EDN2 mRNA was identified mainly in luteal cells but not endothelial cells that expressed the EDN1 gene. Similarly, in preovulatory follicles, EDN2 was expressed in the granulosa cells (GCs) and not in the vascular theca interna. LH and hypoxia are two major stimulants of CL formation. Therefore, GCs were cultured with bovine LH, under hypoxic conditions. GCs incubated with bovine LH resulted in increased EDN2 mRNA 42 h later. CoCl2, a hypoxia-mimicking agent, elevated EDN2 in GCs in a dose-dependent manner. Incubation of the human GC line (Simian virus 40 large T antigen) under low oxygen tension (1%) augmented EDN2 6 and 24 h later. In these two cell types, along with EDN2, hypoxia augmented VEGF. EDN2 induced in GCs changes that characterize the developing CL: cell proliferation as well as up-regulation of vascular endothelial growth factor and cyclooxygenase-2 (mRNA and protein levels). Human chorionic gonadotropin also up-regulated these two genes. Small interfering RNA targeting EDN-converting enzyme-1 effectively reduced its mRNA levels. This treatment, expected to lower the mature EDN2 peptide production, inhibited VEGF mRNA levels and GC numbers. Together these data suggest that elevated EDN2 in the early bovine CL, triggered by LH surge and hypoxia, may facilitate CL formation by promoting angiogenesis, cell proliferation, and differentiation.