bluuebunny/crossref_metadata_2025 huggingface dataset:
Improved electrochemical stability at the surface of La0.8Sr0.2CoO3 achieved by surface chemical modification
Authors: Tsvetkov Nikolai , Lu Qiyang , Yildiz Bilge
Published: April 2015

The degradation of the surface chemistry on perovskite (ABO3) oxides is a critical issue for their performance in energy conversion systems such as solid oxide fuel/electrolysis cells and in splitting of H2O and CO2 to produce fuels. This degradation is typically in the form of segregation and phase separation of dopant cations from the A-site, driven by elastic and electrostatic energy minimization and kinetic demixing. In this study, deposition of Ti at the surface was found to hinder the dopant segregation and the corresponding electrochemical degradation on a promising SOFC cathode material, La0.8Sr0.2CoO3 (LSC). The surface of the LSC films was modified by Ti (denoted as LSC-T) deposited from a TiCl4 solution. The LSC and LSC-T thin films were investigated by electrochemical impedance spectroscopy, nano-probe Auger electron spectroscopy, and X-ray photoelectron spectroscopy (XPS), upon annealing at 420–530 °C in air up to about 90 hours. The oxygen exchange coefficient, kq, on LSC-T cathodes was found to be up to 8 times higher than that on LSC cathodes at 530 °C and retained its stability. Sr-rich insulating particles formed at the surface of the annealed LSC and LSC-T films, but with significantly less coverage of such particles on the LSC-T. From this result, it appears that modification of the LSC surface with Ti reduces the segregation of the blocking Sr-rich particles at the surface, and a larger area on LSC surface (with a higher Sr doping level in the lattice) is available for the oxygen reduction reaction. The stabilization of the LSC surface through Ti-deposition can open a new route for designing surface modifications on perovskite oxide electrodes for high temperature electro- and thermo-chemical applications.
Evidence for anti-inflammatory and antioxidative properties of dried plum polyphenols in macrophage RAW 264.7 cells
Authors: Hooshmand Shirin , Kumar Ajay , Zhang Ji Yao , Johnson Sarah A. , Chai Sheau C. , Arjmandi Bahram H.
Published: April 2015

This study presents the anti-inflammatory and antioxidative properties of dried plum (Prunus domesticaL.) polyphenols in macrophage RAW 264.7 cells.
Correction: Utilization of softwood lignin as both crosslinker and reinforcing agent in silicone elastomers
Authors: Zhang Jianfeng , Chen Yang , Sewell Paul , Brook Michael A.
Published: April 2015

Correction for ‘Utilization of softwood lignin as both crosslinker and reinforcing agent in silicone elastomers’ by Jianfeng Zhang, et al., Green Chem., 2015, 17, 1811–1819.
Atomic emission spectrometry in liquid electrode plasma using an hourglass microchannel
Authors: Kohara Yoshinobu , Terui Yasushi , Ichikawa Megumi , Yamamoto Kazuko , Shirasaki Toshihiro , Kohda Kimiyoshi , Yamamoto Tamotsu , Takamura Yuzuru
Published: April 2015

Liquid electrode plasma atomic emission spectrometry (LEP-AES) is a new elemental analysis method that uses microplasma. LEP forms in a vapor bubble generated inside a narrow-center microchannel by using high-voltage DC pulse power.
Non-contact acoustic capture of microparticles from small plasma volumes
Authors: Evander Mikael , Gidlöf Olof , Olde Björn , Erlinge David , Laurell Thomas
Published: April 2015

An acoustic non-contact method for extracting platelet-derived microparticles from small plasma volumes is presented. The method has higher recovery and can handle smaller sample volumes than conventional differential centrifugation method. It is optimal for the analysis of precious biobank samples with limited volume.
Grain size effect on magnetic and phase transition features in one-dimensional S = 1/2 Heisenberg spin chain molecular crystals
Authors: Yuan Guo-Jun , Sui Yun-Xia , Liu Jian-Lan , Ren Xiao-Ming
Published: April 2015

Magnetic and thermal behaviors and the phase transition nature are strongly influenced by grain size in one-dimensional S = 1/2 molecular spin systems.
A mechanistic investigation of anti-elimination in (Z)-1,2-bis(arylseleno)-1-alkenes and their sulfur analogs
Authors: Tarao Asami , Tabuchi Yukako , Sugimoto Eri , Ikeda Miki , Uchimoto Hitomi , Arimitsu Kenji , Kimura Hiroyuki , Kawasaki Ikuo , Kawahata Masatoshi , Yamaguchi Kentaro , Nishide Kiyoharu
Published: April 2015

Selenoxide anti-elimination in (Z)-1,2-bis(arylseleninyl)-1-alkenes is induced by the Se⋯O interaction, whereas the sulfur analogs lacks this type of nonbonding interaction.
“Armed and disarmed” theory in the addition of an azide radical to glucals
Authors: Wang Wenjun , Yang Zhongyue , Xu Yun , Liu Taibao , Song Tianbang , Zhao Yunyan , Xu Xiufang , Zhao Wei , Wang Peng George
Published: April 2015

“Armed” glucals were prone to undergo kinetic process. The torsional strains govern the selectivity. Meanwhile, “disarmed” glucals preferred thermodynamic radical addition. A sialic acid containing trisaccharide was also synthesized by the method.
Multi stimuli response of a single surfactant presenting a rich self-assembly behavior
Authors: di Gregorio M. C. , Varenik M. , Gubitosi M. , Travaglini L. , Pavel N. V. , Jover A. , Meijide F. , Regev O. , Galantini L.
Published: April 2015

A bile salt derived surfactant shows an unusually rich multi responsive self-assembly, involving interesting opening/closure mechanisms of supramolecular tubules and drastic spectroscopic variations, potentially exploitable in sensing.
A single hybrid optical sensor based on nanoporous silica type SBA-15 for detection of Pb2+and I−in aqueous media
Authors: Karimi Mehdi , Badiei Alireza , Mohammadi Ziarani Ghodsi
Published: April 2015

Simple two-steps post synthesis procedure achieved the functionalized nanoporous SBA-15 as a single hybrid optical sensor for detecting Pb2+and I−ions in aqueous media.
Design of 1-methylimidazolium tricyanomethanide as the first nanostructured molten salt and its catalytic application in the condensation reaction of various aromatic aldehydes, amides and β-naphthol compared with tin dioxide nanoparticles
Authors: Zolfigol Mohammad Ali , Baghery Saeed , Moosavi-Zare Ahmad Reza , Vahdat Seyed Mohammad , Alinezhad Heshmatollah , Norouzi Mohammad
Published: April 2015

1-Methyl imidazolium tricyanomethanide {[HMIM]C(CN)3} as a novel nano molten salt (MS) was synthesized and applied for the synthesis of 1-amidoalkyl-2-naphthols and compared with tin dioxide (SnO2) nanoparticles.
Development of a novel and green microwave-assisted hydrogen peroxide digestion method for total sulphur quantitative extraction in coal samples prior to inductively coupled plasma-optical emission spectroscopy and ion-chromatography determination
Authors: Mketo Nomvano , Nomngongo Philiswa N. , Ngila J. Catherine
Published: April 2015

Novel, rapid and green microwave-assisted digestion using diluted hydrogen peroxide followed by ICP-OES and IC analysis for total sulphur determination in coal samples.
A one-pot three-component synthesis of novel α-sulfamidophosphonates under ultrasound irradiation and catalyst-free conditions
Authors: Belhani Billel , Berredjem Malika , Le Borgne Marc , Bouaziz Zouhair , Lebreton Jacques , Aouf Nour-Eddine
Published: April 2015

A one-pot synthesis of novel α-sulfamidophosphonates is described via a three-component reaction under ultrasound irradiation, catalyst-free and solvent-free conditions. The synthesis has mild conditions, short reaction times, good yields and simple work-up procedures.
Interaction of cesium adatoms with free-standing graphene and graphene-veiled SiO2 surfaces
Authors: Weck Philippe F. , Kim Eunja , Biedermann Grant W.
Published: April 2015

The interaction of Cs adatoms with mono- or bi-layered graphene (MLG and BLG), free-standing or on SiO2 substrate, was investigated using density functional theory. Smaller dipole moments created by Cs adatoms on BLG compared to MLG are predicted.
The effect of submicron bioactive glass particles on in vitro osteogenesis
Authors: Liu Shaoqing , Gong Weiyu , Dong Yanmei , Hu Qing , Chen Xiaofeng , Gao Xuejun
Published: April 2015

Mono-dispersed submicron bioactive glass could enhance the adhesion and osteogenesis of MG-63 cells.
Skutterudites as thermoelectric materials: revisited
Authors: Rull-Bravo M. , Moure A. , Fernández J. F. , Martín-González M.
Published: April 2015

A review of the progress on skutterudites over the last years and future prospects.
Effects of rapid thermal annealing on the properties of AlN films deposited by PEALD on AlGaN/GaN heterostructures
Authors: Cao Duo , Cheng Xinhong , Xie Ya-Hong , Zheng Li , Wang Zhongjian , Yu Xinke , Wang Jia , Shen Dashen , Yu Yuehui
Published: April 2015

AlN films are grown on AlGaN/GaN by PEALD. High-temperature annealing promotes complete nitridation of AlN film, and causes AlN to form a semiconductor-like structure.
Fabrication of different crystallographically oriented TiO2nanotube arrays used in dye-sensitized solar cells
Authors: Wang Liujie , Wang Yi , Yang Yong , Wen Xiaodong , Xiang Hongwei , Li Yongwang
Published: April 2015

Different crystallographically oriented TiO2NTAs were fabricatedviaanodizing Ti film in an electrolyte with different water content.
An investigation on single crystal growth, structural, thermal and optical properties of a series of organic D–π–A push–pull materials
Authors: Gupta Vinod Kumar , Singh Ram Adhar
Published: April 2015

We present the large single crystal growth of a series of donor–π–acceptor (D–π–A) push–pull chromophores (1–4). The thermal, structural and optical properties of the synthesized chromophores were explored. These studies indicate the potential opto-electronic application of these push–pull chromophores.
Theoretical insight into the C–H and C–C scission mechanism of ethane on a tetrahedral Pt4subnanocluster
Authors: Fu Hong-Quan , Su Ben-Fang , Yang Hua-Qing , Hu Chang-Wei
Published: April 2015

The activation mechanism of C2H6on a Pt4cluster has been theoretically investigated in the ground state and the first excited state potential energy surfaces at the BPW91/Lanl2tz, aug-cc-pvtz//BPW91/Lanl2tz, 6-311++G(d, p) level.
Structural and magnetic properties of ferrihydrite nanoparticles
Authors: Masina C. J. , Neethling J. H. , Olivier E. J. , Manzini S. , Lodya L. , Srot V. , van Aken P. A.
Published: April 2015

Electron energy loss spectroscopy (EELS) study of the crystal field environment of Fe in ferrihydrite, a short range ordered iron(iii) oxyhydroxide that has been recently recognized as a good catalyst for Fischer–Tropsch synthesis of liquid hydrocarbons.
A designable magnetic MOF composite and facile coordination-based post-synthetic strategy for the enhanced removal of Hg2+ from water
Authors: Huang Lijin , He Man , Chen Beibei , Hu Bin
Published: April 2015

A magnetic MOF composite with a core–shell nanostructure was prepared and demonstrated to be effective for the removal of Hg2+ from water.
Structural vs. intrinsic carriers: contrasting effects of cation chemistry and disorder on ionic conductivity in pyrochlores
Authors: Perriot Romain , Uberuaga Blas P.
Published: April 2015

Cation disorder liberates and enhances the mobility of structural carriers in pyrochlores. However, depending on the chemistry and type of defect, antisites can trap intrinsic carriers, and reduce the diffusivity.
Electrospun rubber fibre mats with electrochemically controllable pore sizes
Authors: Kerr-Phillips Thomas E. , Woehling Vincent , Agniel Remi , Nguyen Giao T. M. , Vidal Frederic , Kilmartin Paul , Plesse Cédric , Travas-Sejdic Jadranka
Published: April 2015

Electroactive, elastomeric, microfiber mats that show controllable pore size variation upon electrochemical stimulation are produced from semi-interpenetrating polymer networks (s-IPNs).
New strategy for overcoming microleakage: an elastic layer for dental caries restoration
Authors: Yingchao Zhang , Haihuan Gong , Dan Feng , Tengjiaozi Fang , Danfeng Cao , Zuosen Shi , Song Zhu , Zhanchen Cui
Published: April 2015

An elastic layer is applied as a new strategy to prevent the occurrence of microleakage after the dental restoration.
Manipulation of the band gap and efficiency of a minimalist push–pull molecular donor for organic solar cells
Authors: Jiang Yue , Cabanetos Clément , Allain Magali , Liu Ping , Roncali Jean
Published: April 2015

Replacement of a phenyl ring by a methyl in the donor block of a small push–pull system leads to a spectacular decrease of the band gap and a large improvement of hole mobility and photovoltaic conversion efficiency.
Non‐resonant conductor reflectarray element for linear reflection phase
Authors: Lee Woosang , Yi Minwoo , So Joonho , Yoon Young Joong
Published: April 2015

A reflectarray element using a conductor cell with variable height is proposed. It is found that the reflection phase can be tuned by adjusting the height of the conductor cells arranged on the spatially discretised reflector plane. A complete linearised reflection phase thus can be achieved when the proposed conductor cell is used as a unit element. A millimetre‐wave antenna has been designed using the proposed method and it shows 50% aperture efficiency with a half‐wavelength cell height variation.
Text detection and recognition in natural scene with edge analysis
Authors: Yu Chong , Song Yonghong , Meng Quan , Zhang Yuanlin , Liu Yang
Published: April 2015

Text plays an important role in daily life because of its rich information, thus automatic text detection in natural scenes has many attractive applications. However, detecting and recognising such text is always a challenging problem. In this study, the authors propose a method which extends the widely‐used stroke width transform by two steps of edge analysis, namely candidate edge recombination and edge classification. A new method that recognises text through candidate edge recombination and candidate edge recognition is also proposed. In the step of candidate edge recombination, they use the idea of over‐segmentation and region merging. To separate text edge from background, the edge of the input image is first divided into small segments. Then, neighbour edge segments are merged, if they have similar stroke width and colour. Through this step, each character is described by one candidate boundary. In the step of boundary classification, candidate boundaries are aggregated into text chains, followed by chain classification using character‐based and chain‐based features. To recognise text, the grey image is extracted based on the location of each candidate edge after the step of candidate edge recombination. Then, histogram of gradient features and a classifier are used to recognise each character. To evaluate the effectiveness of their method, the algorithm is run on the ICDAR competition dataset and Street View Text database. The experimental results show that the proposed method provides promising performance in comparison with the existing methods.
Probabilistic evaluation of long‐duration voltage variations in distribution networks with wind power plants
Authors: da Silva Antonio Cardoso , Rodrigues Anselmo Barbosa , da Silva Maria da Guia
Published: April 2015

The main aim of this study is to estimate long‐duration voltage variations considering uncertainties associated with stochastic fluctuations in the output power of the wind distributed generation (DG) and system load. In the proposed methodology the uncertainties were represented using the time series models: Fourier analysis and auto‐regressive moving average. These models were used in the quasi‐sequential Monte Carlo simulation method to generate the system operation scenarios. The Monte Carlo simulation method was also used to model failures in the DG. The proposed methodology to estimate long‐duration voltage variations was tested in a test system with 33 buses. The results showed that the insertion of wind DG in the system has a significant impact on the voltage profile. Furthermore, it was demonstrated that failures in DG and fluctuations in the load and wind speed caused large variations on the nodal voltages.
Droplet confinement and leakage: Causes, underlying effects, and amelioration strategies
Authors: Debon Aaron P. , Wootton Robert C. R. , Elvira Katherine S.
Published: April 2015

The applicability of droplet-based microfluidic systems to many research fields stems from the fact that droplets are generally considered individual and self-contained reaction vessels. This study demonstrates that, more often than not, the integrity of droplets is not complete, and depends on a range of factors including surfactant type and concentration, the micro-channel surface, droplet storage conditions, and the flow rates used to form and process droplets. Herein, a model microfluidic device is used for droplet generation and storage to allow the comparative study of forty-four different oil/surfactant conditions. Assessment of droplet stability under these conditions suggests a diversity of different droplet failure modes. These failure modes have been classified into families depending on the underlying effect, with both numerical and qualitative models being used to describe the causative effect and to provide practical solutions for droplet failure amelioration in microfluidic systems.
Thermostating extended Lagrangian Born-Oppenheimer molecular dynamics
Authors: Martínez Enrique , Cawkwell Marc J. , Voter Arthur F. , Niklasson Anders M. N.
Published: April 2015

Extended Lagrangian Born-Oppenheimer molecular dynamics is developed and analyzed for applications in canonical (NVT) simulations. Three different approaches are considered: the Nosé and Andersen thermostats and Langevin dynamics. We have tested the temperature distribution under different conditions of self-consistent field (SCF) convergence and time step and compared the results to analytical predictions. We find that the simulations based on the extended Lagrangian Born-Oppenheimer framework provide accurate canonical distributions even under approximate SCF convergence, often requiring only a single diagonalization per time step, whereas regular Born-Oppenheimer formulations exhibit unphysical fluctuations unless a sufficiently high degree of convergence is reached at each time step. The thermostated extended Lagrangian framework thus offers an accurate approach to sample processes in the canonical ensemble at a fraction of the computational cost of regular Born-Oppenheimer molecular dynamics simulations.
Cluster dynamics models of irradiation damage accumulation in ferritic iron. I. Trap mediated interstitial cluster diffusion
Authors: Kohnert Aaron A. , Wirth Brian D.
Published: April 2015

The microstructure that develops under low temperature irradiation in ferritic alloys is dominated by a high density of small (2–5 nm) defects. These defects have been widely observed to move via occasional discrete hops during in situ thin film irradiation experiments. Cluster dynamics models are used to describe the formation of these defects as an aggregation process of smaller clusters created as primary damage. Multiple assumptions regarding the mobility of these damage features are tested in the models, both with and without explicit consideration of such irradiation induced hops. Comparison with experimental data regarding the density of these defects demonstrates the importance of including such motions in a valid model. In particular, discrete hops inform the limited dependence of defect density on irradiation temperature observed in experiments, which the model was otherwise incapable of producing.
Steady-state benchmarks of DK4D: A time-dependent, axisymmetric drift-kinetic equation solver
Authors: Lyons B. C. , Jardin S. C. , Ramos J. J.
Published: April 2015

The DK4D code has been written to solve a set of time-dependent, axisymmetric, finite-Larmor-radius drift-kinetic equations (DKEs) for the non-Maxwellian part of the electron and ion distribution functions using the full, linearized Fokker–Planck–Landau collision operator. The plasma is assumed to be in the low- to finite-collisionality regime, as is found in the cores of modern and future magnetic confinement fusion experiments. Each DKE is formulated such that the perturbed distribution function carries no net density, parallel momentum, or kinetic energy. Rather, these quantities are contained within the background Maxwellians and would be evolved by an appropriate set of extended magnetohydrodynamic (MHD) equations. This formulation allows for straight-forward coupling of DK4D to existing extended MHD time evolution codes. DK4D uses a mix of implicit and explicit temporal representations and finite element and spectral spatial representations. These, along with other computational methods used, are discussed extensively. Steady-state benchmarks are then presented comparing the results of DK4D to expected analytic results at low collisionality, qualitatively, and to the Sauter analytic fits for the neoclassical conductivity and bootstrap current, quantitatively. These benchmarks confirm that DK4D is capable of solving for the correct, gyroaveraged distribution function in stationary magnetic equilibria. Furthermore, the results presented demonstrate how the exact drift-kinetic solution varies with collisionality as a function of the magnetic moment and the poloidal angle.
Flow reversals in turbulent convection with free-slip walls
Authors: Verma Mahendra K. , Ambhire Siddhesh C. , Pandey Ambrish
Published: April 2015

We perform numerical simulations of turbulent convection for infinite Prandtl number with free-slip walls and study the dynamics of flow reversals. We show interesting correlations between the flow reversals and the nonlinear interactions among the large-scale flow structures represented by the modes (1, 1), (2, 1), (3, 1), and some others. After a flow reversal, the odd modes, e.g., (1, 1) and (3, 1), switch sign, but the even modes, e.g., (2, 2), retain their sign. The mixed modes (1, 2) and (2, 1) fluctuate around zero. Using the properties of the modes and their interactions, we show that they form a Klein four-group Z2 × Z2. We also show that for the free-slip boundary condition, the corner rolls and vortex reconnection are absent during a flow reversal, in contrast to active role played by them in flow reversals for the no-slip boundary condition. We argue that the flow reversals with the no-slip and free-slip boundary conditions are different because they are induced by nonlinearities (u ⋅ ∇)u and (u ⋅ ∇) θ, respectively.
High electron mobility ZnO film for high-performance inverted polymer solar cells
Authors: Lv Peiwen , Chen Shan-Ci , Zheng Qingdong , Huang Feng , Ding Kai
Published: April 2015

High-quality ZnO films (ZnO-MS) are prepared via magnetron sputtering deposition with a high mobility of about 2 cm2/(V·s) and are used as electron transport layer for inverted polymer solar cells (PSCs) with polymer poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene-co-3-fluorothieno[3,4-b]thiophene-2-carboxylate]:[6,6]-phenyl C71-butyric acid methyl ester as the active layer. A significant improvement of JSC, about 20% enhancement in contrast to the devices built on sol-gel derived ZnO film (ZnO-Sol), is found in the ZnO-MS based device. High performance ZnO-MS based PSCs exhibit power conversion efficiency (PCE) up to 8.55%, which is much better than the device based on ZnO-Sol (PCE = 7.78%). Further research on cathode materials is promising to achieve higher performance.
Spin-unrestricted random-phase approximation with range separation: Benchmark on atomization energies and reaction barrier heights
Authors: Mussard Bastien , Reinhardt Peter , Ángyán János G. , Toulouse Julien
Published: April 2015

We consider several spin-unrestricted random-phase approximation (RPA) variants for calculating correlation energies, with and without range separation, and test them on datasets of atomization energies and reaction barrier heights. We show that range separation greatly improves the accuracy of all RPA variants for these properties. Moreover, we show that a RPA variant with exchange, hereafter referred to as RPAx-SO2, first proposed by Szabo and Ostlund [J. Chem. Phys. 67, 4351 (1977)] in a spin-restricted closed-shell formalism, and extended here to a spin-unrestricted formalism, provides on average the most accurate range-separated RPA variant for atomization energies and reaction barrier heights. Since this range-separated RPAx-SO2 method had already been shown to be among the most accurate range-separated RPA variants for weak intermolecular interactions [J. Toulouse et al., J. Chem. Phys. 135, 084119 (2011)], this works confirms range-separated RPAx-SO2 as a promising method for general chemical applications.
Effects of gallium doping and thermal annealing on the physical properties of tin sulphide thin films
Authors: Reghima Meriem , Akkari Anis , Guasch Cathy , Turki-Kamoun Najoua
Published: April 2015

SnS thin films doped with gallium at different concentrations (0%, 4%, 6%, 8%, and 10%) were grown by the chemical bath deposition technique. The structural analysis confirmed previous results on the formation of a mixed face-centered cubic (rock-salt RS) and orthorhombic (OR) microcrystalline structure with the preferential orientations (111)RS and (200)RS in the undoped layers. This crystal structure was confirmed by Raman spectroscopy: the main vibration at 220 cm−1 corresponding to the face-centered cubic SnS was observed in all samples. Small amounts of Sn2S3 phases were also present. The optimum of thin film crystal structure was obtained with a gallium concentration of 4%. This layer was then annealed in nitrogen gas for 30 min at annealing temperatures ranging from 200 °C to 600 °C. X-ray diffraction analysis revealed a structural transition from RS to OR when the annealing temperature was over 500 °C. The optical bandgap energy declined with increasing annealing temperatures. The resistivity deduced from thermally stimulated current measurements indicated a drastic decrease from 1012 Ω cm to 102 Ω cm for, respectively, the as-prepared and annealed films at 600 °C, and was directly correlated with the structural transition. The elemental composition of Sn and S measured by energy dispersive spectroscopy remained near the stoichiometric ratio after annealing.
Magnetic nanocomposites for an efficient valorization of biomass
Authors: Kuncser Victor , Coman Simona M. , Kemnitz Erhard , Parvulescu Vasile I.
Published: April 2015

The recovery of the catalysts from the reaction mixture and their recycling is important goals of the current applied catalysis. The stringent ecological and economical demands for sustainability made this concern even more important for the solid catalysts used in the area of biomass catalytic transformations where the raw material usually is not soluble in most of the organic solvents. Therefore, the solid catalyst cannot be easily separated from the mixture of untransformed raw material and by-products (e.g., humines). However, these goals can be achieved by using magnetic nanoparticles (MNPs) based catalysts. This study reports on the magnetic response of two types of new magnetic nanocomposite catalytic systems, Ru@MNP and Nb@AlF3, used in the synthesis of sorbitol/glycerol and of lactic acid, respectively, by direct cellulose degradation. The results showed that the recovering possibilities of the Nb@AlF3 catalysts, with a weaker magnetic response associated to the so called diluted magnetic oxide systems, are much diminished as compared to Ru@MNP, where the magnetic response is generated using MNP supported catalysts.
Application of sub-micrometer patterned permalloy thin film in tunable radio frequency inductors
Authors: Rahman B. M. Farid , Divan Ralu , Rosenmann Daniel , Wang Tengxing , Peng Yujia , Wang Guoan
Published: April 2015

Electrical tunable meander line inductor using coplanar waveguide structures with patterned permalloy (Py) thin film has been designed and implemented in this paper. High resistivity Si substrate is used to reduce the dielectric loss from the substrate. Inductor is implemented with a 60 nm thick Py deposited and patterned on top of the gold meander line, and Py film is patterned with dimension of 440 nm × 10 μm to create the shape anisotropy field, which in turn increases the FMR frequency. Compared to a regular meanderline inductor without the application of sub-micrometer patterned Py thin film, the inductance density has been increased to 20% for the implemented inductor with patterned Py. Measured FMR frequency of the patterned Py is 4.51 GHz without the application of any external magnetic field. This has enabled the inductor application in the practical circuit boards, where the large external magnet is unavailable. Inductance tunability of the implemented inductor is demonstrated by applying a DC current. Applied DC current creates a magnetic field along the hard axis of the patterned Py thin film, which changes the magnetic moment of the thin film and thus, decreases the inductance of the line. Measured results show that the inductance density of the inductor can be varied 5% by applying 300 mA DC current, larger inductance tunability is achievable by increasing the thickness of Py film.
Structure and composition of iron nanoparticles synthesized using a novel anionic-element complex
Authors: Skoropata E. , Desautels R. D. , Rowe M. , van Lierop J.
Published: April 2015

We use a novel solution-based disassociation synthesis scheme of the ionic complex Fe(LiBH4)2 to form Fe nanoparticles. The complex was formed initially using a gentle mechanochemical process, and the Fe nanoparticles emerged after 4 h of ball milling in an air-free environment. Rietveld refinement of x-ray diffraction measurements in an air-free sample holder identified a Im3¯m α-Fe phase. A room temperature Mössbauer spectrum of the sample presented a six-line spectrum unique to Fe0 metal, and the Fe nanoparticles were extremely well crystallized. Magnetometry results presented a reduced saturation magnetization (e.g., Ms∼ 85 emu/g at 50 K) that had a Bloch-like T2 temperature dependence, consistent with a gap in the magnon fluctuation spectrum due to finite-size effects. The Fe nanoparticles were magnetically soft, with a coercivity ranging from ∼10 to 20 mT with decreasing temperature from 350 K.
Canonical variational completion of differential equations
Authors: Voicu Nicoleta , Krupka Demeter
Published: April 2015

Given a non-variational system of differential equations, the simplest way of turning it into a variational one is by adding a correction term. In the paper, we propose a way of obtaining such a correction term, based on the so-called Vainberg-Tonti Lagrangian, and present several applications in general relativity and classical mechanics.
Patch antenna terahertz photodetectors
Authors: Palaferri D. , Todorov Y. , Chen Y. N. , Madeo J. , Vasanelli A. , Li L. H. , Davies A. G. , Linfield E. H. , Sirtori C.
Published: April 2015

We report on the implementation of 5 THz quantum well photodetector exploiting a patch antenna cavity array. The benefit of our plasmonic architecture on the detector performance is assessed by comparing it with detectors made using the same quantum well absorbing region, but processed into a standard 45° polished facet mesa. Our results demonstrate a clear improvement in responsivity, polarization insensitivity, and background limited performance. Peak detectivities in excess of 5 × 1012 cmHz1/2/W have been obtained, a value comparable with that of the best cryogenic cooled bolometers.
Single-mode interband cascade lasers emitting below 2.8 μm
Authors: Scheuermann Julian , Weih Robert , von Edlinger Michael , Nähle Lars , Fischer Marc , Koeth Johannes , Kamp Martin , Höfling Sven
Published: April 2015

In this work, single-mode distributed feedback (DFB) interband cascade laser (ICL) devices with record short wavelength emission below 2.8 μm are presented. Pulsed measurements based on broad area laser devices with a cavity of 2 mm length and 150 μm width showed threshold current densities of 383 A/cm2 at T = 20 °C and a characteristic temperature T0 of 67 K. Fabricated DFB devices were operated in continuous wave mode at room temperature, with threshold currents of 57 mA and demonstrated side mode suppression ratios of larger than 25 dB. The devices showed current tuning ranges of 7 nm and total (including drive current and temperature) tuning ranges of 12 nm, with respective tuning rates of 21 nm/W, 0.13 nm/mA and 0.29 nm/K. Using the full spectral gain bandwidth of the underlying ICL material, single-mode DFB emission was observed within a wavelength range of 150 nm utilizing different DFB grating periods.
A nonlinear multi-mode wideband piezoelectric vibration-based energy harvester using compliant orthoplanar spring
Authors: Dhote Sharvari , Zu Jean , Zhu Yang
Published: April 2015

In this paper, a nonlinear wideband multi-mode piezoelectric vibration-based energy harvester (PVEH) is proposed based on a compliant orthoplanar spring (COPS), which has an advantage of providing multiple vibration modes at relatively low frequencies. The PVEH is made of a tri-leg COPS flexible structure, where three fixed-guided beams are capable of generating strong nonlinear oscillations under certain base excitation. A prototype harvester was fabricated and investigated through both finite-element analysis and experiments. The frequency response shows multiple resonance which corresponds to a hardening type of nonlinear resonance. By adding masses at different locations on the COPS structure, the first three vibration modes are brought close to each other, where the three hardening nonlinear resonances provide a wide bandwidth for the PVEH. The proposed PVEH has enhanced performance of the energy harvester in terms of a wide frequency bandwidth and a high-voltage output under base excitations.
Correlation of energy conversion efficiency and interface polarization in niobate glass-ceramic for energy-storage applications
Authors: Xue Shuangxi , Liu Shaohui , Zhang Wenqin , Shen Bo , Zhai Jiwei
Published: April 2015

The correlation between energy conversion efficiency and interface polarization was investigated according to the discharge performance and impedance spectroscopy as a function of annealing temperatures in BaO–Na2O–Nb2O5–SiO2 glass ceramic system. The experiment results show that the energy conversion efficiency strongly depends on the interface polarization. The annealing temperature dependence of the energy conversion efficiency is attributed to the variation of interfacial polarization, according to the results of complex impedance analysis.
The Poggendorff Illusion before Poggendorff
Authors: Zavagno Daniele , Daneyko Olga , Stucchi Natale
Published: April 2015

This paper is about the Poggendorff illusion in pictorial artworks. In particular, it deals with the role played by the Poggendorff illusion in the making of the geometrical misalignments in the mosaic known as Lunetta di San Lorenzo in Ravenna (Italy) and in Rubens's oil on panel Descent from the Cross in Antwerp (Belgium). Three experiments are presented. Experiment 1 tested the role of viewing distance in perceived collinearity in the mosaic by asking participants to adjust two ends of a cross in silhouette renderings of the saint projected so to mimic its original size. Results confirm an effect of viewing distance and support the hypothesis that the author of the mosaic became aware of the illusion and attempted to ‘fix’ it. Experiment 2 aimed at verifying perceived collinearity in a book-size version of Rubens's Descent from the Cross by employing a similar adjustment method. Results demonstrate that the Poggendorff illusion affects perceived collinearity in the painting, but perceptual collinearity does not agree with the actual geometrical misalignment in book-size reproductions of the masterpiece. Experiment 3 tested the role of viewing distance in a classic Poggendorff illusion configuration by employing the same setup as in experiment 1. Contrary to what was found in experiment 1, viewing distance did not modulate the magnitude of the illusion in the classic display, suggesting that the outcome of perceived collinearity is sensitive to the complexity of the visual scene. The difference in results between experiments 1 and 3 underscore the necessity of new tests before any reasonable conclusion can be drawn about the whys and wherefores of Rubens's misalignment.
Exhaled breath condensate hydrogen peroxide concentration, a novel biomarker for assessment of oxidative stress in sheep during heat stress
Authors: Chauhan Surinder S. , Celi Pietro , Leury Brian , Liu Fan , Dunshea Frank R.
Published: April 2015

The present study aimed to measure hydrogen peroxide (H2O2) in exhaled breath condensate (EBC) as an index of oxidative stress induced by heat stress (HS) and to evaluate the antioxidant potential of supranutritional levels of selenium (Se) and vitamin E under HS conditions in sheep. Thirty-two Merino × Poll Dorset ewes (in two replicates) were acclimated to indoor individual pen feeding of a pelleted control diet (0.24 g Se and 10 IU of vitamin E/kg DM) for 1 week. Sheep were then randomly allocated to a 2 × 2 factorial design with the respective factors being dietary Se (0.24 and 1.20 mg/kg DM as Sel-Plex) and vitamin E (10 and 100 IU/kg DM) for 2 weeks. After 1 week acclimation to the diets the sheep were placed in metabolism cages in one of two climatic chambers set to either thermoneutral (18−21°C and 40–50% relative humidity) or HS (28−40°C and 30–40% relative humidity) conditions for 1 week. Average respiration rate and rectal temperature were increased (P < 0.001) during HS. Similarly, H2O2 concentration in EBC and plasma reactive oxygen metabolites were increased significantly (P = 0.041 and P = 0.002, respectively), in sheep exposed to HS. The EBC H2O2 concentration was reduced (P < 0.05) in sheep fed the diet supplemented with supranutritional levels of both Se and vitamin E. Sheep supplemented with antioxidants also had lower respiration rates (191 vs 232 breaths/min, P = 0.012) and rectal temperature (40.33 vs 40.58°C, P = 0.039) under peak HS (1300 hours and 1700 hours) compared with those on the control diet indicating an improved capacity to handle HS. These data suggest that the H2O2 concentration in EBC can be utilised as a novel biomarker to demonstrate oxidative stress induced by HS in sheep.
Effects of increasing rates of molasses supplementation and forage quality on the productivity of steers
Authors: Hunter R. A. , Kennedy P. M.
Published: April 2015

This study consisted of several experiments that investigated the feed intakes, and growth rates of steers fed low-quality Angleton grass (Dichanthium aristatum) supplemented with urea and sulfur (dry matter (DM) digestibility, 45%) and medium-quality Rhodes grass (Chloris gayana) (DM digestibility, 58%) when fed either alone or with molasses mixtures (MM, molasses plus nitrogen and phosphorus). Some digestion characteristics of the basal forage diets were also measured. Addition of MM at 1.2 times calculated maintenance energy requirements (M) was associated with about a four-fold increase in microbial crude protein production and a 42% decrease in neutral detergent fibre digestibility. In the first growth experiment, MM at 0M, 0.45M, 0.90M and 1.35M was offered and mostly consumed before forage was offered ad libitum. The initial mean weight of the steers was 240 kg. Consumed MM comprised 0%, 21%, 38% and 50% of the total DM intake for Angleton grass and 0%, 19%, 33% and 41% for Rhodes grass. The corresponding mean liveweight (LW) gains were 0.06, 0.31, 0.73 and 0.83 kg/day for steers fed Angleton grass and 0.61, 0.90, 1.02 and 1.13 kg/day for steers fed Rhodes grass. In a second experiment, MM was offered to steers (initially 370 kg) at the same time as forage. Offered MM comprised 0, 0.40, 0.80 and 1.20M of the calculated metabolisable energy (ME) requirements for maintenance. Consumed MM comprised 0%, 20%, 36% and 48% of the total DM intake for Angleton grass diets and 0%, 18%, 28% and 32% for Rhodes grass diets. The corresponding mean LW gains were –0.09, 0.36, 0.58 and 0.70 kg/day for Angleton grass diets and 0.63, 0.67, 0.80 and 0.94 kg/day for Rhodes grass diets. The method of presentation of the MM had only minor effects on the amounts and proportions of forage and the MM consumed and on the LW gains of the steers, expressed as g/kg0.75 LW per day to allow for differences in initial LW between experiments. Using modifications to the scheme of SCA (1990) to predict maintenance energy requirements, a value for efficiency of use of ME for growth was calculated from growth rates of steers fed Rhodes grass. When MM with an assumed content of 11 MJ ME/ kg DM was added to the forage diets, the calculated ME content of forage decreased with increased MM content, consistent with depression of fibre digestion. The relationships for the separate experiments indicated that at 50% MM in the diet, the magnitudes of the depression in the calculated ME content of the forages were 20–37% for Rhodes grass and 18–33% for Angleton grass.
Nickel-hyperaccumulating species of Phyllanthus (Phyllanthaceae) from the Philippines
Authors: Quimado Marilyn O. , Fernando Edwino S. , Trinidad Lorele C. , Doronila Augustine
Published: April 2015

Botanical exploration on ultramafic sites in Palawan, Surigao and Zambales has resulted in the discovery of a new hypernickelophore species (nickel (Ni) concentration >1%) of Phyllanthus (Phyllanthaceae). This paper reports in detail the Ni uptake of populations of P. erythrotrichus in Candelaria, Masinloc and Santa Cruz, Zambales, and confirms the status of P. securinegoides in Taganito, Surigao del Norte, which had been analysed only through herbarium specimens, and these were compared with a known hypernickelophore, P. balgooyi, which was collected in Narra and Puerto Princesa, Palawan. Nickel content of the dried leaves, stems and root tissues was quantified using atomic absorption spectrophotometer. P. erythrotrichus and P. securinegoides both had more than 10 000 µg g–1 Ni in the leaves, whereas the roots had 1195 µg g–1 and 4636 µg g–1. P. balgooyi accumulated 6319 µg g–1 of Ni in the leaves, whereas the roots had a higher Ni concentration of up to 8116 µg g–1, respectively. All three species had values of translocation factor and enrichment factor of >1.0, implying that all species have great potential in phytoremediation, specifically, phytoextraction of Ni. These three species of Phyllanthus are prominent in ultramafic scrub communities and, hence, should be used in ecological restoration of mined-out Ni lateritic areas. The implications of the unique adaptation of these species are also discussed in relation to a conservation strategy for their natural populations.
Failure of science, death of nature
Authors: Recher Harry F.
Published: April 2015

As a people, Australians have lost contact with the world of nature, risking the collapse of civilisation. One factor in the alienation of nature in Australia is the failure of the scientific community to take responsibility for the technology created by the knowledge generated from scientific research. Science has failed to protect Australia’s flora and fauna. Scientists must communicate more widely with society, but need to be educated on how to communicate and on their ethical responsibilities to others and other species. Government needs to show leadership in environmental management and nature conservation, while conservationists need to ‘invert the paradigm’, taking a new, less anthropocentric approach to conservation. None of this is possible in a market-place economy and Australians must move to an economic system that is ecocentric. This will not be easy as it requires a reduction in the consumption of resources and a smaller population.
Sperm superoxide dismutase is associated with bull fertility
Authors: Grant Kamilah E. , de Oliveira Rodrigo V. , Hennington Bettye Sue , Govindaraju Aruna , Perkins Andy , Stokes John , Rowe Dennis , Topper Einko , Kaya Abdullah , Moura Arlindo , Memili Erdogan
Published: April 2015

Decreasing mammalian fertility and sperm quality have created an urgent need to find effective methods to distinguish non-viable from viable fertilising spermatozoa. The aims of the present study were to evaluate expression levels of β-tubulin 2C (TUBB2C), heat shock protein 10 (HSP10), hexokinase 1 (HXK1) and superoxide dismutase 1 (SOD1) in spermatozoa from Holstein bulls with varying fertility using western blotting and to analyse the biological networks of these key sperm proteins using a bioinformatics software (Metacore; Thomson-Reuters, Philadelphia, PA, USA). The rationales behind this study were that the sperm proteins play crucial roles in fertilisation and early embryonic development in mammals and ascertaining the biological networks of the proteins helps us better understand sperm physiology and early mammalian development. The results showed that expression of SOD1 was higher in spermatozoa from high fertility bulls (P < 0.05) and that SOD1 is the best protein to diagnose bulls based on the fertility index (P < 0.05). Using Metacore analysis, we identified an SOD1 network with pathways and linkages with other relevant molecules. We concluded that SOD1 sperm expression is associated with in vivo bull fertility. The findings are important because they illuminate molecular and cellular determinants of sperm viability and the identified protein markers can be used to determine bull fertility.
Spindle configuration and developmental competence of in vitro-matured bovine oocytes exposed to NaCl or sucrose prior to Cryotop vitrification
Authors: Arcarons Núria , Morató Roser , Spricigo Jozé F. W. , Ferraz Marcia A. M. M. , Mogas Teresa
Published: April 2015

In the present study we examined whether exposure to high concentrations of NaCl or sucrose before vitrification improves the cryotolerance of in vitro-matured bovine oocytes. In Experiment 1, oocytes were exposed to different concentrations of NaCl (375–1517 mOsm) or sucrose (375–812 mOsm) for 1 h. On the basis of the results of this experiment, in Experiment 2 oocytes were exposed to 0.25% NaCl (375 mOsmol) or 2.77% sucrose (375 mOsmol) solution, vitrified and warmed. Microtubule and chromosome configurations were examined by immunocytochemistry. In Experiment 3, in vitro embryo development was assessed after vitrification of oocytes with or without 2.77% sucrose (375 mOsmol) pretreatment. There was a similar percentage of oocytes showing normal spindle configurations in the sucrose-pretreated and control groups. Higher rates of abnormal spindles were found in groups treated with NaCl or sucrose solutions with >375 mOsmol. After vitrification and warming, a significantly higher percentage of oocytes with normal chromosome configurations was recorded for oocytes exposed to 375 mOsmol sucrose solution before vitrification compared with the control vitrified oocytes. However, these percentages were significantly lower than those recorded in untreated controls. Cleavage and blastocyst rates were higher in non-vitrified than vitrified oocytes. In conclusion, pretreatment with 375 mOsmol NaCl or sucrose solution had no adverse effects on the spindle status of vitrified–warmed cow oocytes. However, sucrose pretreatment offered no benefits for embryo development.