bluuebunny/crossref_metadata_2025 huggingface dataset:
The Structure, Distribution, and Biomass of the World's Forests
Authors: Pan Yude , Birdsey Richard A. , Phillips Oliver L. , Jackson Robert B.
Published: October 2013

Forests are the dominant terrestrial ecosystem on Earth. We review the environmental factors controlling their structure and global distribution and evaluate their current and future trajectory. Adaptations of trees to climate and resource gradients, coupled with disturbances and forest dynamics, create complex geographical patterns in forest assemblages and structures. These patterns are increasingly discernible through new satellite and airborne observation systems, improved forest inventories, and global ecosystem models. Forest biomass is a complex property affected by forest distribution, structure, and ecological processes. Since at least 1990, biomass density has consistently increased in global established forests, despite increasing mortality in some regions, suggesting that a global driver such as elevated CO2 may be enhancing biomass gains. Global forests have also apparently become more dynamic. Advanced information about the structure, distribution, and biomass of the world's forests provides critical ecological insights and opportunities for sustainable forest management and enhancing forest conservation and ecosystem services.
Adjoint Equations in Stability Analysis
Authors: Luchini Paolo , Bottaro Alessandro
Published: October 2013

The objective of this article is to review some developments in the use of adjoint equations in hydrodynamic stability theory. Adjoint-based sensitivity analysis finds both analytical and numerical applications much beyond those originally imagined. It can be used to identify optimal perturbations, pinpoint the most receptive path to break down, select the most destabilizing base-flow defect in a nominally stable configuration, and map the structural sensitivity of an oscillator. We focus on two flow cases more closely: the noise-amplifying instability of a boundary layer and the global mode occurring in the wake of a cylinder. For both cases, the clever interpretation and use of direct and adjoint modes provide key insight into the process of the transition to turbulence.
The Physicochemical Hydrodynamics of Vascular Plants
Authors: Stroock Abraham D. , Pagay Vinay V. , Zwieniecki Maciej A. , Michele Holbrook N.
Published: October 2013

Plants live dangerously, but gracefully. To remain hydrated, they exploit liquid water in the thermodynamically metastable state of negative pressure, similar to a rope under tension. This tension allows them to pull water out of the soil and up to their leaves. When this liquid rope breaks, owing to cavitation, they catch the ends to keep it from unraveling and then bind it back together. In parallel, they operate a second vascular system for the circulation of metabolites though their tissues, this time with positive pressures and flow that passes from leaf to root. In this article, we review the current state of understanding of water management in plants with an emphasis on the rich coupling of transport phenomena, thermodynamics, and active biological processes. We discuss efforts to replicate plant function in synthetic systems and point to opportunities for physical scientists and engineers to benefit from and contribute to the study of plants.
Applied Pharmacogenomics in Cardiovascular Medicine
Authors: Weeke Peter , Roden Dan M.
Published: October 2013

Interindividual heterogeneity in drug response is a central feature of all drug therapies. Studies in individual patients, families, and populations over the past several decades have identified variants in genes encoding drug elimination or drug target pathways that in some cases contribute substantially to variable efficacy and toxicity. Important associations of pharmacogenomics in cardiovascular medicine include clopidogrel and risk for in-stent thrombosis, steady-state warfarin dose, myotoxicity with simvastatin, and certain drug-induced arrhythmias. This review describes methods used to accumulate and validate these findings and points to approaches—now being put in place at some centers—to implementing them in clinical care.
IgG4-Related Disease
Authors: Mahajan Vinay S. , Mattoo Hamid , Deshpande Vikram , Pillai Shiv S. , Stone John H.
Published: October 2013

Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is an immune-mediated condition that can affect almost any organ and is now being recognized with increasing frequency. IgG4-RD is characterized by a lymphoplasmacytic infiltrate composed of IgG4+plasma cells, storiform fibrosis, obliterative phlebitis, and mild to moderate eosinophilia. The diagnosis of IgG4-RD unifies many eponymous fibroinflammatory conditions that had previously been thought to be confined to single organs. IgG4-RD lesions are infiltrated by T helper cells, which likely cause progressive fibrosis and organ damage. IgG4 antibodies are generally regarded as noninflammatory. Although autoreactive IgG4 antibodies are observed in IgG4-RD, there is no evidence that they are directly pathogenic. Rituximab-induced B cell depletion in IgG4-RD leads to rapid clinical and histological improvement accompanied by swift declines in serum IgG4 concentrations. Although IgG autoantibodies against various exocrine gland antigens have been described in IgG4-RD, whether they are members of the IgG4 subclass is unknown. The contribution of autoantibodies to IgG4-RD remains unclear.
Electrodeposition and Electroless Deposition of NiWP Alloys
Authors: Djokić Stojan S.
Published: October 2013

Electrodeposition and electroless deposition of NiWP alloys from a solution containing NaH2PO2, Na2WO4, NiSO4 and Na3C6H5O7 is investigated in this work. Electrodeposition at room temperature (22oC) leads to a production of NiP alloys with a composition (12%P and 88%Ni) practically independent on current density within the investigated range (20 to 100 mA/cm2). At elevated temperatures the incorporation of W into deposit was observed. An increase in temperature from 22 oC to 80 oC leads to the increase in W content from 0 to 12 %. The efficiency of NiWP alloy deposition increases with an increase in temperatures. This observation is attributed by the simultaneous electroless deposition due to presence of hypophosphite, which acts as a reducing agent of Ni(II) ions at temperatures above 60 oC in the system investigated.
Pulse Electrodeposition of NiMoW Alloys
Authors: Sun Shaopeng , Podlaha Elizabeth J.
Published: October 2013

NiMoW electrodeposition was investigated in a boric acid-citrate, ammonia free electrolyte at room temperature by pulse electrodeposition. Rotation cylinder working electrodes were employed to maintain a well controlled boundary layer, and deposits were fabricated galvanostatically. The compositions of deposits were analyzed by x-ray fluorescence (XRF). Frequency and duty cycle were varied to examine the effect of pulse electrodeposition on the induced codeposition of NiMoW. It was observed that an increase of duty cycle can lead a decrease of Mo content and an increase of W content in deposit, but no significant change in Ni, attributed to possible differences in adsorbed molybdenum and tungsten intermediate species. It was also observed that pulse electrodeposition helps to tune the density of cracks in the deposits by varying the duty cycle.
Impact of the Applied Potential on the Copper Nucleation
Authors: Delbos Elise , El Belghiti Hanane , Mercier Dimitri , Vigneron Jackie , Bouttemy Muriel , Etcheberry Arnaud
Published: October 2013

In this work, we propose an alternative way to produce thin film solar cells (CIGS or CZTS) using an electrodeposition process presenting the advantage to be less constraining and cheaper than CVD or PVD processes. The first technologic key point consists in the deposition of a thin (~100 nm), uniform and adherent copper layer on the initial molybdenum substrate. This conductive copper layer is then used as a support for a multi-stack plating. Results concerning the study of the copper nucleation mechanism have been presented in a previous paper (1). In the present research work, the influence of the applied potential on the copper nucleation will be highlighted. Combining electrochemical analyses, SEM-FEG (Scanning Electron Microscopy – Field Emission Gun) imaging and nano-Auger measurements, an optimized range of potential is defined.
Electrodeposition of Cobalt-Manganese Alloy Coatings onto Metallic SOFC Interconnects
Authors: McCrabb Heather , Lucatero Savidra , Hall Tim D , Snyder Stephen , Kagajwala Burhanuddin , Zhang Hui , Liu Xingbo , Taylor E. J.
Published: October 2013

A pulse electrodeposition process is being developed and validated for coating ferritic stainless steel solid oxide fuel cell interconnects with a cobalt-manganese alloy. The electrodeposition process produces the alloy coatings from a single acidic sulfate based electrolyte containing cobalt and manganese ions, sodium gluconate, ammonium sulfate and boric acid. Subsequent to electrodeposition, the alloy coatings are oxidized at elevated temperatures to form spinel structures. Experiments demonstrate that the pulse waveform parameters influence the chemical composition of the alloy coating. Survival of long term exposure at elevated temperatures has shown that the coatings function as a barrier to chrome diffusion toward the surface with minimal increase in the area specific resistance.
Pulse Electrodeposition of Natural Uranium in 2-Propanol Acidic Ionic Solution
Authors: Saliba-Silva Adonis Marcelo , Oliveira Eneas Tavares de , Garcia Rafael Henrique Lazzari , Durazzo Michelangelo
Published: October 2013

A regular way to produce samples for alpha-spectrometry and other nuclear emissions could be by means of electrodeposition. Uranium electrodeposition may also be used to fabricate irradiation targets for radiopharmaceutical production. In this work, the electrodeposition of natural uranium was made by pulsed potential in galvanostatic state over nickel substrate, having a cathodic area of 2 cm2. The samples have been exposed to UO2(NO3)2 acidic concentrated solution diluted 1:20 in 2-propanol, having final concentration at 50 mM [U] with pH<1. The pulsed potential varied between two levels, from 0 V to −10 V and from 0 V to −15 V, inside a tubular electrochemical cell made of quartz. The pulsed electrodeposition had a rectangular potential wave with duty cycle of 75% and a frequency of 25 Hz, with a constant duration of 1400 s. The higher alpha emission activity that was obtained from the oxide/hydroxide electrodeposit reached the level of 30 Bq/cm2 for a cathodic potential polarization at 0V/-15V during 1400 s of pulsed electrodeposition. Explanation of uranium electrodeposition at lower pHs was based on potential migration of polarity at the cathode during pulsing potential, allowing production of OH- and nascent oxygen in anodic microregions.
Preparation and Characterization of Non-Precious Metal Fuel Cell Catalysts via Chemical Modification of Carbon Surfaces
Authors: Mavilla Stephanie G. , MacLean Brian J. , Easton E. Bradley
Published: October 2013

Preparation of non-precious metal catalysts (NPMCs) via chemical surface modification of carbon black with 5,6-diamino-1,10-phenanthroline (aphen) was completed. A diazonium coupling reaction was used to covalently attach aphen to the carbon surface and ratios of aphen to carbon were varied. The impact of this loading on the oxygen reduction reaction (ORR) was investigated. Cyclic voltammograms (CVs) were obtained under nitrogen to assess the redox activity of the phenanthroline type groups on the surface. Peaks at approximately 611 mV versus standard hydrogen electrode appear for each material and become larger with increased loading of aphen. Introduction of iron followed by pyrolysis at 700 °C results in increased activity towards the ORR and decreased hydrogen peroxide production.
Electrochemical Disinfection of Human Urine for Water-Free and Additive-Free Toilets Using Boron-Doped Diamond Electrodes
Authors: Raut Akshay S. , Cunningham Garry B. , Parker Charles B. , Klem Ethan J. D. , Stoner Brian R. , Deshusses Marc A. , Glass Jeffrey T.
Published: October 2013

We report the development of an electrochemical disinfection system for human urine, which does not require the addition of any external water or chemical reagents. It is designed to minimize energy consumption so that it may derive its energy from solar panels. The system will be part of a modular outdoor toilet for use in developing countries. The system was tested with a physiological saline solution and an organic dye to determine minimum-energy operating conditions. Disinfection was then quantified using synthetic urine and Escherichia coli (E. Coli) as indicator organisms. The colony forming unit (CFU) count of E. Coli was reduced from >109 CFU/100 ml to within World Health Organization permissible limits after treatment. Effects of suspended fecal matter on disinfection efficiency were also studied.
First-Principles Study on Li2MSiO4 (M=Mn, Fe, Co, Ni) as Cathode Materials of Lithium Ion Battery
Authors: Tsubakiyama Kenta , Kudo Yusuke , Yamashita Koichi
Published: October 2013

First-principles calculations were performed to analyze the electrochemical properties of Li2MSiO4 (M=Mn, Fe, Co, Ni), which is a promising stable large capacity cathode material for lithium ion battery. In spite of these expectations, previous studies have revealed that they cannot work well. First, we performed calculations on the structural change according to charging and discharging. From these calculations, it was revealed that some crystals are stable even in deep charged states, but others are not. Second, we have predicted how the phase separation occurs in these materials. We have also calculated the voltage profiles of these materials and confirmed that the calculated results agree with the experimental ones. However, we could not find the ideal material which can perform “two-electron reactions” reversibly. If further works could make the potential window of electrolytes wider, Li2MSiO4 can be the candidate for stable and large capacity cathode materials.
Effects of Oxidation States of Np on Polarization Curve of Stainless Steel in Boiling 3M-HNO3
Authors: Kato Chiaki , Ueno Fumiyoshi , Yamamoto Masahiro , Ban Yasutoshi , Uchiyama Gunzo , Nojima Yasuo , Fujine Sachio
Published: October 2013

It is well known that some certain metal ions in boiling nitric acid cause corrosion acceleration of stainless steel. Neptunium ion from fission products contained in reprocessing solution is known as corrosion accelerator of the stainless steel. Neptunium has several oxidation states (IV, V and VI) in nitric acid solution (up to 3M-HNO3). The metal ions with the REDOX reaction having near the potential of nitric acid promote corrosion of stainless steel but it is not clear why slight amount of the metal ion accelerates corrosion in boiling nitric acid solution. Simultaneous evaluating the coexisting oxidation state Np(IV), Np(V) and Np(VI) and the electrochemical behaviors on stainless steel in nitric acid solution is required in order to understand the corrosion acceleration mechanism. Specially designed electrochemical test cell integrated with optical cell for spectroscopic analysis was developed for this purpose. From results of electrochemical tests, cathode reaction on stainless steel was activated by Np ions. Np(VI) ion made corrosion potential shift nobler than Np(V) and nobler corrosion potential causes accelerating corrosion of stainless steel in nitric acid solution. From results of spectroscopic analysis for oxidation states of Np ion, Np(V) was easily oxidized to Np(VI) in nitric acid solution and Np(VI) was stable state in boiling 3M-HNO3. It was considered that role of Np ions was mediator to accelerate corrosion due to activating cathode reaction and re-oxidizing cycle in boiling 3M-HNO3.
Corrosion in Nuclear Waste Containers
Authors: Fergus Jeffrey W.
Published: October 2013

One of the challenges for the continued use and expansion of nuclear power generation is the disposal of radioactive waste materials. The long lifetimes require the identification of stable geological formations with non-aggressive environments combined with engineered multi-barrier containment systems. In this paper, the corrosion behavior of alloys used in containment systems for storage of nuclear waste in geological sites will be reviewed.
Investigation of Water Adsorption on Metal Oxide Surfaces under Conditions Representative of PuO2 Storage Containers
Authors: Murphy Patrick Martin , Boxall Colin , Taylor Robin J. , Woodhead David A.
Published: October 2013

We have developed a QCM (Quartz Crystal Microbalance) based method for direct gravimetric determination of water adsorption on PuO2 surrogate surfaces, especially CeO2, under conditions representative of those in a typical PuO2 storage can. In this application, the method of transduction of the QCM relies upon the linear relationship between the resonant frequency of piezoelectrically active quartz crystals and the mass adsorbed on the crystal surface. The effect of high temperature on the resonant frequency of coated QCM crystals has been compensated for by modeling the temperature dependence of the frequency response of the surrogate coated-QCM crystal in the absence of water.
Pt/ITO Electrocatalysts with Excellent ORR Activity and Stability
Authors: Liu Ying , Mustain William E
Published: October 2013

Sn-doped indium oxide (ITO) nanoparticles were platinized using a galvanic displacement technique and investigated as electrocatalysts for the oxygen reduction reaction (ORR). The electrocatalysts were found to have very high mass and specific ORR activity: 621 ± 31 mA/mgPt and 750 ± 0.04 mA/cm2, respectively –far exceeding the 2017 DOE targets. The Pt/ITO catalysts also exhibited impressive stability with the ORR half wave potential shifting only 4 mV after 1,000 potential cycles between 0.0 and 1.4 V vs. RHE.
Redox-Induced Ion-Pairing between Anionic Amphiphiles and Ferrocenylalkanethiolate Self-Assembled Monolayers
Authors: Dionne Eric R. , Sultana Tania , Badia Antonella
Published: October 2013

The interfacial electrochemistry of self-assembled monolayers of ferrocenyldodecanethiolate on gold electrodes in aqueous solutions of the anionic surfactants sodium n-hexyl sulfate and sodium n-dodecyl sulfate is reported. The effects of surfactant micellization and alkyl chain length on the redox potential of the monolayer-bound ferrocene are examined. The non-ideal behavior of the sodium alkyl sulfate solution at concentrations above the critical micelle concentration leads to a non-Nernstian variation of the redox potential. A longer alkyl chain length results in an increased ion-pairing ability and the oxidation of the tethered ferrocene at lower potential.
Fabrication of ZnO/Absorber Heterostructures for Nanostructured Solar Cells
Authors: Salazar Raul , Aldakov Dmitry , Bellet Daniel , Puyoo Etienne , Lévy-Clément Claude , Ivanova Valentina
Published: October 2013

The development of low-band-gap semiconducting materials for the extremely thin absorber (eta) solar cell using cheap and scalable methods is the main objective of this work. The eta-solar cell is composed of all inorganic materials consisting of an extremely thin layer of absorbing material (1.1 < Eg < 1.8 eV) sandwiched between nanostructured transparent electron and hole conductors (Eg ≥ 3.3 eV). The photosensitization of the electrodeposited ZnO nanowires with conformal layers of CdS and CdSe prepared by successive ionic layer adsorption and reaction (SILAR) is proposed. The improvement of the absorber structural and optical properties by annealing and chemical treatment is achieved. SILAR method insures a conformal layer formation on the entire nanowire surface. Thus prepared heterostructures exhibit optimal optical features. The effects of the core/shell heterostructure interface (ZnO/absorber) were studied in a photoelectrochemical cell using the 3I-/I3- redox electrolyte as in a standard DSSC. The effects of the chemical treatment and annealing step of the photosensitizing shell are studied.
Synthesis of Nanocoral Structured TiO2 and its Photoelectrical Performance in Dye Sensitized Solar Cells
Authors: Li Yang , Sun Qiong , Sun Xianmiao , Dong Lifeng
Published: October 2013

TiO2 nanorods with multidirectional coral-like structure were synthesized through a facial hydrolysis and condensation method by using titanium oxysulfate (TiOSO4) as the precursor. TiO2 nanorods were continuously formed on substrates in aqueous TiOSO4-H2O2, which resulted in the deposition of amorphous films. The phase transformation to anatase and rutile TiO2 could be achieved through the sintering treatment. The morphology and crystalline properties of the samples were characterized by X-ray diffraction, field emission scanning electron microscopy and high-resolution transmission electron microscopy. In addition, the dye sensitized solar cells (DSSCs) were fabricated with this nanocoral structured TiO2 for the photoanode, and the highest photoelectrical conversion efficiency (η) of 0.9% was obtained from the DSSC that composed of 600 °C sintered TiO2.
Comparison of Resistive Switching between Tantalum Oxides Deposited by Atomic Layer Deposition and E-Beam Physical Vapor Evaporation
Authors: Kang Yuhong , Potnis Tanmay , El-Helw Sarah , Liu Tong , Orlowski Marius K.
Published: October 2013

Performance of Cu/TaxOy/Pt devices is compared between tantalum oxide deposited by atomic layer deposition (ALD) and electron beam physical vapor evaporation (EBPVD). Formation, set and reset of Cu and oxygen vacancy (VO) conductive filaments (CF) are evaluated for both dielectrics and related to the respective material properties. XPS data shows that ALD forms a stoichoimetric Ta2O5, while EBPVD results in oxygen deficient TaOx films. Forming voltages of Cu and Vo CFs for ALD Ta2O5 devices are considerably higher than for EBPVD TaOx devices and its Vform, Vset, Vreset and Ron distributions are much tighter than the corresponding distributions for EBPVD TaOx. Overall, ALD Ta2O5 devices outperform those with EBPVD TaOx.
Nanostructured Platinum-Copper Electrocatalysts for the Oxidation of Borohydride
Authors: Tamašauskaitė-Tamašiūnaitė Loreta , Balčiūnaitė Aldona , Zabielaitë Ausrine , Stankevičienė Ina , Selskis Algirdas , Norkus Eugenijus
Published: October 2013

This work is focused on the use and study of the nanostructured platinum-copper catalysts deposited on the titanium surface by a two-step process which involves electroless copper deposition followed by a spontaneous Pt displacement from the hexachloro-complex solution as electrocatalysts for the oxidation of BH4
– ions in an alkaline medium. The morphology and composition of as-prepared catalysts were characterized using field-emission scanning electron microscopy and energy dispersive X-ray spectroscopy. The electrochemical behavior of the as-prepared nano-Pt(Cu)/Ti catalysts was examined by means of the cyclic voltammetry and chrono-techniques. The electrocatalytic activity of the catalysts towards the oxidation of BH4
– ions was compared with that of bare Pt and Cu/Ti electrodes.
Electrocatalytic Activity of the Nanostructured Au-Co Catalysts Deposited on the Titanium towards Borohydride Oxidation
Authors: Tamašauskaitė-Tamašiūnaitė Loreta , Jagminienė Aldona , Balčiūnaitė Aldona , Zabielaitė Ausrine , Selskis Algirdas , Norkus Eugenijus
Published: October 2013

The nanostructured gold-cobalt catalysts were deposited onto titanium surface via the galvanic displacement technique. The electrocatalytic activity of the as-prepared nanostructured Au(Co)/Ti catalysts was examined in respect to the oxidation of BH4
– ions in an alkaline media by the cyclic voltammetry and chrono-techniques. The nanostructured catalysts were prepared via galvanic displacement reactions between hierarchical Co thin films prepared by electroless deposition and a solution of HAuCl4. The surface morphology and composition of the samples were characterized using Field Emission Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy. The prepared nanostructured Au(Co)/Ti catalysts exhibit an enhanced electrochemical activity towards electrochemical oxidation of H2 generated by catalytic borohydride hydrolysis and oxidation of BH4
– ions.
An Initial Study of Coating Nickel Salen on Gold Electrode via Self-Assembly
Authors: Brown Drew K. , Ji Chang
Published: October 2013

Two novel nickel(II) salens modified with a side alkanethiol chain containing either six or eight methylene groups (Ni(II)L-(CH2)6SH or Ni(II)L-(CH2)8SH) were obtained by a multistep synthetic route. The catalysts were used to coat the gold electrode via self-assembly with the formation of a compact monolayer. Cyclic voltammetry (CV) was employed to examine the electrochemical properties of the immobilized nickel salen molecules, which have been found to undergo oxidative polymerization at the gold surface. The resulting polymerized catalyst film, which is fairly stable and robust, can efficiently block the diffusion of ferrocene to the electrode surface. Moreover, a new redox CV feature was observed for the polymerized nickel salen, which can be potentially applied for various catalytic reduction or oxidation reactions. This initial study shows that it is feasible to immobilize metal Schiff base complexes on gold electrode using alkanethiol substituents as the anchors for the development of analytical sensors.
Synthesis of Decacationic C70 Bisadducts by Incorporating Covalently BoundElectron-Donors for Enhancement of Radical-Based Type-I PDT
Authors: Wang Min , Huang Liyi , Dai Tianhong , Sperandio Felipe F , Huang Ying-Ying , Hamblin Michael , Chiang Long
Published: October 2013

We designed, synthesized, and characterized two types of highly water-soluble C70 monoadduct, C70[>M(C3N6
+C3)2]-(I‒)10 (LC17), and bisadducts, C70[>M(C3N6
+C3)2][>M(C3N6C3)2] (LC18). Each of these compounds consist of a well-defined decacationic quaternary ammonium iodide moiety with ten positive charges per C70 for increasing water-solubility and the ability to target pathogenic bacterial cells. The structural modification enables them to act as broad-spectrum antibacterial nano-PDT drugs. We found that white light was more effective with LC17 while UVA light was more effective with LC18 to the antimicrobial effects against human pathogens, Gram-positive (Staphylococcus aureus) and Gram-negative species (Escherichia coli and Acinetobacter baumannii). Both compounds were effective in a mouse model of Gram-negative 3rd-degree burn infections. The observation led to our proposition that the attachment of an additional electron-donating deca(tertiary ethylenylamino)malonate arm to C70, giving a product of LC18, allowed the moiety to act as a potent electron source and increased the generation yield of hydroxyl radicals under UVA illumination. This demonstrated a new approach in enhancing HO·-induced radical-killing (Type-I photochemistry) of pathogenic bacteria.
Multifunctional Nanostructured Materials for Oxidation of Methanol
Authors: Zoladek Sylwia , Rutkowska Iwona Agnieszka , Blicharska Magdalena , Gierwatowska M. , Kulesza Pawel J.
Published: October 2013

Herein, we report on our investigation on the use of the aqueous solution of the phosphotungstate heteropolyblue as a reducing agent and stabilizer for the synthesis of gold nanoparticles deposited on multiwalled carbon nanotubes and functionalized with CO-type surface groups. Chemical reduction method allowed producing multi-walled carbon nanotube-supported gold (Au/MWCNTs) catalysts with high dispersion and loading of Au up to 5 wt%. The average diameter of Au nanoparticles on MWCNTs was 2.0-4.5 nm. The resulting gold nanoparticles were subsequently cleaned from their inorganic capping agents (PW12O40
3-) by converting to alkaline medium (NaOHaq). The high dispersion of gold nanoparticles at MWCNTs (pretreated with HCl, HNO3 and H3PMo12O40) was attributed to the presence of a high density of active sites for nucleation created during the functionalization procedure. The nanocomposite system based on multi-walled carbon nanotubes decorated with gold nanoparticles was probed towards electrocatalytic oxidation of methanol in alkaline medium under voltammetric conditions. The existence of mesopores created at the surfaces of multi-walled carbon nanotubes originated from an easy accessibility of the OH- groups and methanol molecules at the electrocatalytic interface. The chemical functionalization of the open ends and the side walls of MWCNTs played a vital role in tailoring their electrochemical properties. Electrochemical studies demonstrated the promotional effect of quick pseudofaradaic reactions of surface polar groups created on carbon nanotubes during the methanol electrooxidation process.
Oxidation of Ethanol and Its Derivatives on Well Defined Pt Single Crystal Electrodes Vicinal to Pt(111): A Comparative Study
Authors: Arán-Ais Rosa , Abe Santos Nathalia , Villulas Hebe Mercedes , Feliu Juan M.
Published: October 2013

The oxidation of ethanol (EtOH) at Pt(111) electrodes is dominated by the 4e path leading to acetic acid. The inclusion of surface defects such as those present on stepped surfaces leads to an increase of the reactivity towards the most desirable 12e path leading to CO2 as final product. This path is also favored when the methyl group is more oxidized, as in the case of ethylene glycol (EG) that spontaneously decomposes to CO on Pt(111) electrodes, thus showing a more effective breaking of the C-C bond. Some trends in reactivity can be envisaged when other derivative molecules are compared at well-ordered electrodes. This strategy was used in the past, but the improvement in the electrode pretreatment and the overall information available on the subject suggest that relevant information is still missing.
Graphene and N-Doped Graphene Coated with SnO2 Nanoparticles as Supercapacitor Electrodes
Authors: Xu Lili , Yu Jianhua , Zhu Qianqian , Wang Xiaoxia , Dong Lifeng
Published: October 2013

In this work, both graphene and nitrogen-doped graphene coated with SnO2 nanoparticles were synthesized through a chemical-solution route, graphene-based thin films were prepared by a blade coating method, and solid-state supercapacitors were fabricated employing graphene-based films and polyvinyl alcohol (PVA)-H3PO4 gel as electrodes and electrolyte, respectively. Scanning electron microscopy was used to characterize the morphology of the obtained graphene based films. Energy dispersive X-ray and X-ray diffraction analyses were carried out to investigate the composition and crystal structure of the as-obtained graphene based materials. The electrochemical performance of the as-fabricated supercapacitors was measured using cyclic voltammetry. Thermo gravimetric analysis was conducted to study the thermal stability of the added polymer (acrylic resin) during heat treatment.
Nanofiber-Based Electrodes for High Power Supercapacitors
Authors: Tran Chau , Kalra Vibha
Published: October 2013

Fabrication of novel three-dimensional material architectures is essential for successful development of energy storage devices that allow high rate operation along with sufficient energy capacity. To this end, we report a facile methodology to fabricate hierarchically-porous nanofiber-based electrodes for electric double layer capacitors. In particular, blends of polyacrylonitrile and a sacrificial polymer at different compositions were electrospun into non-woven nanofiber mats with the fiber diameter in the range of 200–400 nm and the mat thickness of 150-200 µm. Electrospun nanofiber mats were then subjected to carbonization to obtain porous carbon nanofibers (CNFs) as polyacrylonitrile converted to carbon and the sacrificial polymer decomposed out creating intra-fiber pores resulting in high specific surface areas of upto 1600 m2/g. No additional chemical or physical activation process was used. Electrochemical measurements in aqueous electrolyte showed large specific capacitance of up to 210 F g−1 at a high cyclic voltammetry scan rate of 100 mV s−1. These materials retain 75% capacitance at a large current density of 20 A g−1 indicating excellent power handling capability. These porous CNFs provided an ideal three-dimensional, free standing (without any binders) electrode design with multi-levels of pore sizes; through-connected Macropores (~500nm-1 µm), created due to inter-fiber spacing in the nanofiber mat & Micro (d <2 nm) and/or Meso pores (2<d<50 nm) created in each nanofiber due to decomposition of sacrificial polymer.While the intra-fiber pores provided large specific surface areas and hence large capacity, the inter-fiber pores facilitated the permeation of electrolyte to the carbon surfaces to allow fast charge adsorption/desorption and enhanced power handling capability.
Glass Wool Material as Alternative Separator for Higher Rating Electric Double Layer Capacitor
Authors: Ahmad Noorden Zulkarnain Bin , Sugawara Sougoro , Matsumoto Satoshi
Published: October 2013

The paper evaluates the electrochemical performance of glass wool as an alternative separator material for electric double layer capacitor (EDLC) construction. Using aqueous solution of sulfuric acid as the electrolyte, two-electrode coin-type capacitors were constructed by sandwiching the electrolyte-containing glass wool with two activated carbon sheets. Electrochemical properties of the capacitors were characterized by cyclic voltammetry, galvanostatic and impedance spectroscopy measurements. The glass wool-based capacitor outperforms the practically used cellulose separator with higher power and energy densities of 566 W/kg and 15 kJ/kg, respectively. The implementation of glass wool separator will enable the utilization of high concentration aqueous electrolytes, which lead to higher rating EDLC at relatively lower cost compared to organic solution-based capacitor.
Influence of Vanadate Additive on the Properties of Cerium Conversion Coatings on AZ91 Magnesium Alloys
Authors: Lo Wen-Hsin , Lin Chao-Sung
Published: October 2013

The present study investigates the microstructure and corrosion resistance of the cerium conversion coating on AZ91 magnesium plates in the cerium nitrate/hydrogen peroxide aqueous solution with and without sodium metavanadate. The microstructure characterization shows that the conversion coating displays a two-layered structure, an inner porous layer and an outer compact layer. Moreover, the size and population density of blisters are significantly reduced with the addition of NaVO3 to the solution. The corrosion resistance is improved due to the decrease in defects within the coating.
The Effect of Selective Oxidation On Galvanizing and Galvannealing Reactions of Dual-Phase Steels
Authors: Kang Hsiu-Yu , Lin Ko-Chun , Lin Chao-Sung , Chen Hon Bor
Published: October 2013

Dual Phase Steels (DP steels), which have high strength with an excellent formability, offer potential for weight savings in the automotive industry because of their high strength and excellent formability. Alloying elements, such as Mn, Mo, Si, and Cr, are commonly added in DP steels. The alloy elements not only enhance the mechanical properties of the steel substrate, but also play an important role in the following GI and GA process. In this work, two kinds of DP steels were used, labeled HDA and HDB, in which HDB had more Mn, Si, Cr than HDA. Further GA treatments resulted in more Fe-Zn IMCs for HDA than HDB samples. This retardation in the Fe-Zn alloy reaction in HDB can be attributed to the selective oxidation at the steel surface during the annealing process prior to hot dipping. Those external selective oxides were too small to be observed by the SEM, but can be confirmed by TEM observations and OCP tests. Moreover, GDOES analyses clearly revealed that those IMCs were formed by the transformation from the Fe-Al inhibition layer.
Corrosion Improvement of Oxidized Co by Silane Thin Films in Neutral Solution
Authors: Mabuchi Katsumi
Published: October 2013

Surface pretreatments by 1, 2-Bis(triethoxysilyl) ethane (BTSE), 1.2-bis [triethoxysilylpropyl]amine (BTSPA), and 1.2-bis [triethoxysilyl]tetrasulfide (BTSPS) were evaluated from the viewpoint of improving corrosion resistance of a thin cobalt film. These silane-coupling layers are formed on cobalt oxide by immersion in a pretreatment solution including hydrogen peroxide. Immersions in BTSE and BTSPA pretreatment solutions were found to significantly improve corrosion resistance of the cobalt film. When the former (BTSE) pretreatment solution was applied, the corrosion resistance improved with pretreatment time; however, adversely, when the latter pretreatment was applied, corrosion resistance deteriorated with pretreatment time. On the other hand, the corrosion was not inhibited by the immersion in BTAPS pretreatment solution. These behaviors are explained by applying in terms of the hard and soft acid-base (HSAB) principle.
Separation of Metallic and Semiconducting Single-Walled Carbon Nanotubes by Density Gradient Ultracentrifugation
Authors: Lang Min , Gao Jinling , Wu Xiuli , Xiu Shu , Huang Yao , Lian Yongfu
Published: October 2013

In this paper, SWNTs synthesized by an improved arc discharge method were chemically purified, and then sonically dispersed in an aqueous cosurfactant solution of sodium deoxycholate and sodium dodecyl sulfate. Density gradient ultracentrifugation showed that the separation of such chemically purified SWNTs by diameter or electronic type could be improved by optimizing rotation speed, time and temperature. UV-vis-NIR absorbance and Raman scattering spectra showed that the purity of the metallic SWNTs was estimated to be 74% mainly composed of (9,9) tube, and the purity of the semiconducting SWNTs to be 98% mainly composed of (15,8) tube.
Kupffer cells and activation of endothelial TLR4 coordinate neutrophil adhesion within liver sinusoids during endotoxemia
Authors: McDonald Braedon , Jenne Craig N. , Zhuo Lisheng , Kimata Koji , Kubes Paul
Published: October 2013

A key pathological feature of the systemic inflammatory response of sepsis/endotoxemia is the accumulation of neutrophils within the microvasculature of organs such as the liver, where they cause tissue damage and vascular dysfunction. There is emerging evidence that the vascular endothelium is critical to the orchestration of inflammatory responses to blood-borne microbes and microbial products in sepsis/endotoxemia. In this study, we aimed to understand the role of endothelium, and specifically endothelial TLR4 activation, in the regulation of neutrophil recruitment to the liver during endotoxemia. Intravital microscopy of bone marrow chimeric mice revealed that TLR4 expression by non-bone marrow-derived cells was required for neutrophil recruitment to the liver during endotoxemia. Furthermore, LPS-induced neutrophil adhesion in liver sinusoids was equivalent between wild-type mice and transgenic mice that express TLR4 only on endothelium ( tlr4−/−Tie2tlr4), revealing that activation of endothelial TLR4 alone was sufficient to initiate neutrophil adhesion. Neutrophil arrest within sinusoids of endotoxemic mice requires adhesive interactions between neutrophil CD44 and endothelial hyaluronan. Intravital immunofluorescence imaging demonstrated that stimulation of endothelial TLR4 alone was sufficient to induce the deposition of serum-derived hyaluronan-associated protein (SHAP) within sinusoids, which was required for CD44/hyaluronan-dependent neutrophil adhesion. In addition to endothelial TLR4 activation, Kupffer cells contribute to neutrophil recruitment via a distinct CD44/HA/SHAP-independent mechanism. This study sheds new light on the control of innate immune activation within the liver vasculature during endotoxemia, revealing a key role for endothelial cells as sentinels in the detection of intravascular infections and coordination of neutrophil recruitment to the liver.
Lactobacillus caseistrain Shirota protects against nonalcoholic steatohepatitis development in a rodent model
Authors: Okubo Hirofumi , Sakoda Hideyuki , Kushiyama Akifumi , Fujishiro Midori , Nakatsu Yusuke , Fukushima Toshiaki , Matsunaga Yasuka , Kamata Hideaki , Asahara Takashi , Yoshida Yasuto , Chonan Osamu , Iwashita Misaki , Nishimura Fusanori , Asano Tomoichiro
Published: October 2013

Gut microbiota alterations are associated with various disorders. In this study, gut microbiota changes were investigated in a methionine-choline-deficient (MCD) diet-induced nonalcoholic steatohepatitis (NASH) rodent model, and the effects of administering Lactobacillus casei strain Shirota (LcS) on the development of NASH were also investigated. Mice were divided into three groups, given the normal chow diet (NCD), MCD diet, or the MCD diet plus daily oral administration of LcS for 6 wk. Gut microbiota analyses for the three groups revealed that lactic acid bacteria such as Bifidobacterium and Lactobacillus in feces were markedly reduced by the MCD diet. Interestingly, oral administration of LcS to MCD diet-fed mice increased not only the L. casei subgroup but also other lactic acid bacteria. Subsequently, NASH development was evaluated based on hepatic histochemical findings, serum parameters, and various mRNA and/or protein expression levels. LcS intervention markedly suppressed MCD-diet-induced NASH development, with reduced serum lipopolysaccharide concentrations, suppression of inflammation and fibrosis in the liver, and reduced colon inflammation. Therefore, reduced populations of lactic acid bacteria in the colon may be involved in the pathogenesis of MCD diet-induced NASH, suggesting normalization of gut microbiota to be effective for treating NASH.
Peristalsis and propulsion of colonic content can occur after blockade of major neuroneuronal and neuromuscular transmitters in isolated guinea pig colon
Authors: Sia T. C. , Brookes S. J. , Dinning P. G. , Wattchow D. A. , Spencer N. J.
Published: October 2013

We recently identified hexamethonium-resistant peristalsis in the guinea pig colon. We showed that, following acute blockade of nicotinic receptors, peristalsis recovers, leading to normal propagation velocities of fecal pellets along the colon. This raises the fundamental question: what mechanisms underlie hexamethonium-resistant peristalsis? We investigated whether blockade of the major receptors that underlie excitatory neuromuscular transmission is required for hexamethonium-resistant peristalsis. Video imaging of colonic wall movements was used to make spatiotemporal maps and determine the velocity of peristalsis. Propagation of artificial fecal pellets in the guinea pig distal colon was studied in hexamethonium, atropine, ω-conotoxin (GVIA), ibodutant (MEN-15596), and TTX. Hexamethonium and ibodutant alone did not retard peristalsis. In contrast, ω-conotoxin abolished peristalsis in some preparations and reduced the velocity of propagation in all remaining specimens. Peristalsis could still occur in some animals in the presence of hexamethonium + atropine + ibodutant + ω-conotoxin. Peristalsis never occurred in the presence of TTX. The major finding of the current study is the unexpected observation that peristalsis can occur after blockade of the major excitatory neuroneuronal and neuromuscular transmitters. Also, the colon retained an intrinsic polarity in the presence of these antagonists and was only able to expel pellets in an aboral direction. The nature of the mechanism(s)/neurotransmitter(s) that generate(s) peristalsis and facilitate(s) natural fecal pellet propulsion, after blockade of major excitatory neurotransmitters, at the neuroneuronal and neuromuscular junction remains to be identified.
Estimation of thigh muscle cross-sectional area by single- and multifrequency segmental bioelectrical impedance analysis in the elderly
Authors: Yamada Yosuke , Ikenaga Masahiro , Takeda Noriko , Morimura Kazuhiro , Miyoshi Nobuyuki , Kiyonaga Akira , Kimura Misaka , Higaki Yasuki , Tanaka Hiroaki
Published: October 2013

Bioelectrical impedance analysis (BIA) has been used to estimate skeletal muscle mass, but its application in the elderly is not optimal. The accuracy of BIA may be influenced by the expansion of extracellular water (ECW) relative to muscle mass with aging. Multifrequency BIA (MFBIA) can evaluate the distribution between ECW and intracellular water (ICW), and thus may be superior to single-frequency BIA (SFBIA) to estimate muscle mass in the elderly. A total of 58 elderly participants aged 65–85 years were recruited. Muscle cross-sectional area (CSA) was obtained from computed tomography scans at the mid-thigh. Segmental SFBIA and MFBIA were measured for the upper legs. An index of the ratio of ECW and ICW was calculated using MFBIA. The correlation between muscle CSA and SFBIA was moderate ( r = 0.68), but strong between muscle CSA and MFBIA ( r = 0.85). ECW/ICW index was significantly and positively correlated with age ( P < 0.001). SFBIA tends to significantly overestimate muscle CSA in subjects who had relative expansion of ECW in the thigh segment ( P < 0.001). This trend was not observed for MFBIA ( P = 0.42). Relative expansion of ECW was observed in older participants. The relative expansion of ECW affects the validity of traditional SFBIA, which is lowered when estimating muscle CSA in the elderly. By contrast, MFBIA was not affected by water distribution in thigh segments, thus rendering the validity of MFBIA for estimating thigh muscle CSA higher than SFBIA in the elderly.
MHD Stagnation-Point Flow of Casson Fluid and Heat Transfer over a Stretching Sheet with Thermal Radiation
Authors: Bhattacharyya Krishnendu
Published: October 2013

The two-dimensional magnetohydrodynamic (MHD) stagnation-point flow of electrically conducting non-Newtonian Casson fluid and heat transfer towards a stretching sheet have been considered. The effect of thermal radiation is also investigated. Implementing similarity transformations, the governing momentum, and energy equations are transformed to self-similar nonlinear ODEs and numerical computations are performed to solve those. The investigation reveals many important aspects of flow and heat transfer. If velocity ratio parameter (B) and magnetic parameter (M) increase, then the velocity boundary layer thickness becomes thinner. On the other hand, for Casson fluid it is found that the velocity boundary layer thickness is larger compared to that of Newtonian fluid. The magnitude of wall skin-friction coefficient reduces with Casson parameter (β). The velocity ratio parameter, Casson parameter, and magnetic parameter also have major effects on temperature distribution. The heat transfer rate is enhanced with increasing values of velocity ratio parameter. The rate of heat transfer is enhanced with increasing magnetic parameter M for B > 1 and it decreases with M for B < 1. Moreover, the presence of thermal radiation reduces temperature and thermal boundary layer thickness.
Sustaining Biodiesel Production via Value-Added Applications of Glycerol
Authors: Babajide Omotola
Published: October 2013

The production of biofuels worldwide has been significant lately due to the shift from obtaining energy from nonrenewable energy (fossil fuels) to renewable sources (biofuels). This energy shift arose as a result of the disturbing crude petroleum price fluctuations, uncertainties about fossil fuel reserves, and greenhouse gas (GHG) concerns. With the production of biofuels increasing considerably and the current global biodiesel production from different feedstock, reaching about 6 billion liters per year, biodiesel production costs have been highly dependent on feedstock prices, ranging from 70 to 25; of total production costs, and in comparison with the conventional diesel fuel, the biodiesel is currently noncompetitive. An efficient production process is, therefore, crucial to lowering biodiesel production costs. The question of sustainability, however, arises, taking into account the African diverse conditions and how vital concerns need to be addressed. The major concern about biodiesel production costs can be reduced by finding value-added applications for its glycerol byproduct. This paper, thus, provides an overview of current research trends that could overcome the major hurdles towards profitable commercialization of biodiesel and also proposes areas of opportunity probable to capitalize the surplus glycerol obtained, for numerous applications.