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In this paper, Ag 8 SnS 6 powder was synthesized by the one-pot method, then prepared into Ag 8 SnS 6 and Selenization treated Ag 8 SnS x Se 6-x thin films. The effects brought by the amounts of added Se powder during the annealing process on the product phases, structures, and morphologies are characterized, and the electrochemical property and the cell efficiency as assembled into the counter electrode (CEs) for dye-sensitized solar cells (DSSCs) were investigated. It showed Se into the Ag 8 SnS 6 lattice occupied the site of S to transform into Ag 8 SnS x Se 6-x. And the thin film also became unflatten since the particles became larger after Se doping. The cell efficiency of Ag 8 SnS x Se 6-x CEs reached 4.26%, which was increased by 28.31% compared to that of Ag 8 SnS 6 CEs. Ag 8 SnS x Se 6-x CEs performed lower charge transfer resistance (Rct) and (△EPP), and an increased△E value between the conduction band level of CEs and the redox potential of electrolyte. After 10 cycles, the almost unchanged cathode/anode current density implied the Ag 8 SnS x Se 6-x CEs received good structure stability. Selenization treatment was able to facilitate electron transport and enhance the electrocatalytic activity, and as expected to be a promising method in improving the performance of the DSSCs. [ABSTRACT FROM AUTHOR]

It has been a longstanding question how stars are packed or distributed in the universe. Here we show that the spatial distribution of stars follows some geometric rules although there may be local inhomogeneities. The topological and metric properties of their Voronoi tessellations exhibit a lognormal distribution. Moreover, these distributions can be connected with those established for the packing of spheres, corresponding to the loosest packing state. The findings provide a new angle to understand the packing structure of stars in the universe. Unlabelled Image • The packing of stars is studied in terms of the topological and metric properties of the Voronoi tessellation. • The spatial distribution of stars is shown to follow some geometric rules, quantified by the lognormal distribution. • The packing of stars can be linked to the packing of spheres, corresponding to the loosest packing state. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The nature behind the capacity deterioration of HSAs is clarified. • The atomic coordination state is critical for the corrosion resistance of HSAs. • The as-designed alloy shows the longest cycle life of 2415 cycles. • The usage cost of Ni-MH battery based on this alloy is 1/5 that of Li-ion battery. Abstract The intrinsic relationship between the atomic structure and macroscopic corrosion behavior has been established, which proposes that the atomic coordination state is another key factor affecting the corrosion resistance and cycling life of hydrogen storage alloys besides elements electronegativity. The density functional theory simulation and experimental results confirm the predictions, shedding light on the design of ultra-long-life hydrogen storage alloys. The as-designed alloy La 0.73 Ce 0.17 Y 0.1 Ni 3.75 Co 1.0 Mn 0.3 Al 0.35 exhibits an ultra-long 2415-cycle life, which is almost five times that of the traditional commercial alloy. The usage costs of nickel metal hydride battery based on this alloy is only 1/5 that of Li-ion battery, showing broad market prospect. [ABSTRACT FROM AUTHOR]

In order to compete with Li-ion batteries, the discharge capacity and cycling life of nickel metal hydride batteries need to be further improved. However, this is rather difficult due to poor performances of the negative electrode materials—hydrogen storage alloys. In this work, a new strategy is proposed for designing hydrogen storage alloys with high capacity and long cycling life through theoretical analysis and density functional theory simulation, which points out that it is crucial to substitute Ni atoms inside the alloy with Mg by the precise control of stoichiometric ratio and Mg content. The candidate alloy La 0.62 Mg 0.08 Ce 0.2 Y 0.1 Ni 3.25 Co 0.75 Mn 0.2 Al 0.3 [corresponding to (LaCeYMg) (NiCoMnAl) 4.5 ] exhibits a high capacity of 326.7 mAh g −1 and a capacity retention of 80% after a long cycling life of 928 cycles, showing great potential for applications in nickel metal hydride batteries. The design strategy also provides new insights into the development of new-type high-performance hydrogen storage alloys. [ABSTRACT FROM AUTHOR]

The possibilities of ferromagnetism induced by nonmagnetic dopants (Cu, Zn) in double perovskite S r 2 A l T a O 6 at B sites are investigated by density functional theory. Calculations reveal that substitutions at Ta-site tend to form high spin electronic configurations and could induce ferromagnetism which can be attributed to the hole-mediated p - d hybridization between Cu (or Zn) e g states and the neighboring O 2p states. The dopants preferably substitute at Al-site and adopt low spin electronic structures. Due to the smaller hole concentration and weaker covalent intensity, S r 2 A l T a O 6 with dopants at Al-site exhibits p -type metallic semiconductors without spin polarization. [ABSTRACT FROM AUTHOR]

Pure, La-doped, and (La,Co)-codoped BiFeO 3 ceramic samples were prepared by solid-state reaction. By means of dielectric permittivity, electric modulus spectroscopy, and impedance analysis, the dielectric properties of the samples were systematically investigated in the temperature range of 140–330 K and frequency range of 20–10 7  Hz. Three, two, and one dielectric relaxations were found in pure, La-doped, and (La,Co)-codoped samples, respectively, in the investigated temperature window. Post-sintering annealing studies reveal that both p - and n -types carriers coexist in the samples with the p -type carriers (holes) being the major carriers acting as relaxing species. The dielectric properties are determined by the competition between the n -type carriers (electrons) and the holes. La-doping and (La,Co) dual doping enhance the role played by the holes. Impedance analysis shows that the low-temperature (high-frequency) relaxation is a polaronic relaxation resulting from the hoping motion of holes inside grains. The middle-temperature (frequency) and high-temperature (low-frequency) relaxations are Maxwell-Wagner relaxations caused by the hoping motion of holes blocked by grain boundaries and sample-electrode contacts, respectively. These results underscore the role of sample preparing conditions in the dielectric properties of BiFeO 3 and suggest that optimizing the preparing procedures would be a promising strategy to achieve superior properties of BiFeO 3 . [ABSTRACT FROM AUTHOR]

The interaction between an edge dislocation and a semi-infinite long crack penetrating a circular inhomogeneity is investigated. Using Riemann–Schwartz’s symmetry principle integrated with the analysis of singularity of complex function, the closed form solutions of complex potentials and stress field are obtained. Stress intensity factor at the crack tip and image force acting on edge dislocation are calculated. As a result, the crack penetrating inhomogeneity and interface has a strong influence on the interaction between an edge dislocation and an elastic circular inhomogeneity. It attracts the edge dislocation evidently and because of the influence of crack, the edge dislocation has a stable equilibrium position in matrix. Under a certain condition, the edge dislocation can reduce the stress intensity factor near crack tip. If the distance between the edge dislocation and crack tip is fixed, there always exists a critical value of position angle of edge dislocation at which the shielding or anti-shielding effect is maximal. Shielding effect to the stress intensity factor increases when edge dislocation approaches the tip of crack. In addition, the material mismatch also has a great influence on image force, shielding and anti-shielding effects. [ABSTRACT FROM AUTHOR]

Erbium orthoferrite (ErFeO 3 ) ceramics were prepared by the solid state reaction. The dielectric properties of the samples were investigated over a broad temperature (120–850 K) in the frequency range ranging from 50 Hz to 10 MHz. The sample shows three dielectric responses without colossal dielectric constant behavior. The first dielectric response occurring around 200 K is a thermally activated relaxation and argued to be a polaron relaxation caused by the hopping motions of charge carriers between Fe 2+ and Fe 3+ . The second response occurring around 550 K shows a relaxor-like behavior. It contains two relaxation processes: dipolar-type and Maxwell–Wagner-type relaxations induced by the hopping motions of oxygen vacancies. The third one occurring around 725 K also exhibits as a relaxor-like behavior. It was found to be an artificial effect caused by negative capacitance. [ABSTRACT FROM AUTHOR]

• Nano-composites of ZnS@Ag 8 SnS 6 (ATS) were synthesized by a stepwise heating method. • Catalytic activity of the composites for Methylene Blue degradation is enhanced. • In the optimal case, rate constant of 0.7012 h−1 of ZnS@ ATS was achieved. Nanoscale Ag 8 SnS 6 (ATS) and ZnS@ATS heterogeneous composites were synthesized by a stepwise heating method. The as-prepared ATS nanoparticles were mainly irregular polygons with crystal size ranging from 35 to 120 nm, and transformed to cotton shape particles when nano ZnS was added during the synthesis process. Photocatalytic properties of the as-prepared ATS, ZnS and ZnS@ATS were investigated using Methylene Blue solution as the target degradation. It is resulted that the rate constant of the catalysts first increases and then decreases with the content of ZnS in ZnS@ATS composites. In the optimal case of 0.5 mmol ZnS@ATS, rate constant of 0.7012 h−1 was achieved which is 7.3 times that of ZnS and 2.3 times that of ATS. The improvement mainly comes from enhancing separation and transfer efficiency of photogenerated electron-hole pairs at the grain boundaries of ZnS@ATS. [ABSTRACT FROM AUTHOR]

• Memory effect of ME coupling in Co4Ta2O9 is revealed in the form of polarization memory effect: ME poling induced polarization below Néel temperature is recovered after Co4Ta2O9 is heated to paramagnetic nonpolar phase and then cooled to antiferromagnetic polar phase without being poled. • Polarization memory effect is attributed to polar nanoregions in paramagnetic phase due to short-range magnetic ordering as evidenced by heat capacity data deduced magnetic entropy. • If the applied magnetic field in paramagnetic phase is weakened, polarization memory effect is enhanced, which is ascribed to the less change of spin structure. If we switch the direction of this magnetic field, the polarization after reentering antiferromagnetic phase is also reversed. • ME coupling memory effect is also reflected in electric field dependent magnetization after the second cooling process without being poled. The two aspects of ME coupling are strongly correlated. Memory effect of magnetoelectric (ME) coupling is observed in antiferromagnetic Co 4 Ta 2 O 9 ME poling generated polarization below Néel temperature is retrieved after Co 4 Ta 2 O 9 is warmed to paramagnetic phase and then cooled to antiferromagnetic phase without being poled. This effect is ascribed to polar nanoregions in paramagnetic phase due to short range magnetic ordering as evidenced by temperature dependent magnetic entropy. If the applied magnetic field in paramagnetic phase is weakened, the memory effect is strengthened, which is ascribed to the less change of spin alignment induced by the weaker magnetic field. If we switch this magnetic field, the polarization when reentering polar phase is also reversed. Furthermore, the memory effect is also reflected in electric field dependent magnetization after the second cooling process without being poled. [ABSTRACT FROM AUTHOR]

Abstract: The changes of structural, energetic, magnetic and electronic properties in double perovskite oxide Sr2AlTaO6 due to introducing intrinsic vacancies are investigated by first-principles calculation. Calculated results show that although both Al and Ta vacancies could induce ferromagnetism the nature of induced ferromagnetism is different. Ferromagnetism driven by Al vacancy originates from the remarkably spin-polarized 2p x state of nearest O atoms, whereas that induced by Ta vacancy mainly comes from the partially filled spin-polarized 2p y and 2p z states of nearest O atoms. Sr2AlTaO6 with O vacancy is nonmagnetic but energetically more favorable than that with the other three vacancies. [Copyright &y& Elsevier]

Highlights: [•] Both Al and Nb vacancies could induce ferromagnetism in . [•] Ferromagnetism driven by Al vacancy originates from the 2p x state of nearest O atoms. [•] Ferromagnetism induced by Nb vacancy comes from 2p y and 2p z states of nearest O atoms. [•] with O vacancy is energetically more favorable than with others. [ABSTRACT FROM AUTHOR]

Abstract: The present contribution provides a perspective on the degree to which modern computational methods can be harnessed to guide the design of polymeric dielectrics. A variety of methods, including quantum mechanical ab initio methods, classical force-field based molecular dynamics simulations, and data-driven paradigms, such as quantitative structure–property relationship and machine learning schemes, are discussed. Strategies to explore, search and screen chemical and configurational spaces extensively are also proposed. Some examples of computation-guided synthesis and understanding of real polymer dielectrics are also provided, highlighting the anticipated increasing role of such computational methods in the future design of polymer dielectrics. [Copyright &y& Elsevier]

Abstract: Na0.5K0.5NbO3 ceramic samples were prepared via the solid-state reaction route. The low-frequency (20–107 Hz) dielectric properties were investigated in the temperature range from room temperature to 1073K. Two relaxations were observed in the spectra of electric modulus. Relaxation 1 occurs in the orthorhombic phase, which was ascribed to be related to the oxygen-vacancy clusters. Relaxation 2 appears in the tetragonal and cubic phases. It behaves as a Maxwell–Wagner-type and polaron-type relaxation in the tetragonal and cubic phase, respectively. [Copyright &y& Elsevier]

Abstract: The effect of various Sb-terminated GaAs(001) templates on the growth of InAs was investigated by varying the As flux. The growth of InAs under In-rich growth conditions on Sb-terminated GaAs(001)-(2×3), (2×4) and (2×8) templates was demonstrated to occur in the Stranski-Krastanov (SK) growth mode, in contrast to the Sb-free case, where the growth process follows the Franck-van der Merwe (FM) growth mechanism. The observed antimony dependent change of growth mode from FM to SK is qualitatively explained by the decrease of the surface energy of the growing InAs layer caused by the segregation of Sb on the surface of the InAs(001). [Copyright &y& Elsevier]

Abstract: The reaction sequence between liquid Sn–3Ag–0.5Cu solder and solid Au/Pd(P)/electrolytic-Ni films was carefully examined using a field-emission transmission electron microscope at different exposure times (15s, 30s, and 120s). After 15s of exposure, the uppermost layer of Au was removed from the interface and a portion of the Pd(P) film remained. At this stage of the reaction, the predominant products were PdSn3 and Pd3P. After 30s of exposure, Pd(P) was completely exhausted, and three additional intermetallic species, including Pd–Sn–P, Pd6P, and Pd15P2, nucleated. After 120s of exposure, the aforementioned species were destroyed, and Cu and Ni were involved in the reaction. The predominant product became (Cu,Ni)6Sn5, and the nucleation of a nanocrystalline Ni2SnP layer in the middle of (Cu,Ni)6Sn5 resulted. These results suggest that Pd and P play a vital role in the early stage of soldering reaction, even though the Pd(P) film is only a few submicrons thick and its P content is quite low (2–5%). [Copyright &y& Elsevier]

Abstract: We report our experimental results of a hybrid which has both the cooling-responsive shape memory effect (SME) and water-responsive SME. The hybrid is designed based on the concept of shape memory hybrid (SMH), and is made of a plastic sponge (as elastic component) filled with Poloxamer 407 (P407) gel (as transition component). It is observed that the hybrid is able to recover its original shape upon immersing into 0°C water in less than one minute (due to “melting” of P407 gel upon cooling), while upon immersing into 20°C water, the recovery time is about one hour (due to dissolving of P407 gel in the water). Apparently, cooling for shape recovery is a complement to heating induced SME as in almost all traditional thermo-responsive shape memory materials. Mechanical properties of these samples are characterized by cyclic uniaxial compression test. Our experimental results reveal the compatibility and feasibility of P407 hybrid for biomedical applications inside human body. Potential biomedical applications are further discussed. [Copyright &y& Elsevier]

Abstract: In this work, the dielectric properties of La0.8Bi0.2Fe0.7Mn0.3O3 ceramics have been investigated in a temperature range of 76–320K and a frequency range of 300 Hz–10MHz. Two thermally activated dielectric relaxations were observed with the activation energy around 0.283±0.007eV for the low-temperature relaxation and 0.268±0.007eV for the high-temperature relaxation. Annealing in N2 and O2 can destroy and create the high-temperature relaxation, respectively. But the treatments have no significant influence on the low-temperature relaxation. The low-temperature relaxation was found to be bulk effect related to the dipolar effect due to the hopping polarons, and the high-temperature relaxation was associated with the Maxwell–Wagner relaxation due to surface-layer effect caused by hopping polarons blocked and trapped at the surfaces of the sample. [Copyright &y& Elsevier]

Abstract: Wurtzite structure ZnCoO thin films with c-axis preferential orientation were synthesized on c-plane sapphire substrates by using pulsed laser deposition (PLD) technique under various oxygen pressures. The structural, optical and magnetic properties of the films were investigated. When the oxygen pressure was relatively low (<1.3Pa), the cobalt was incorporated in the ZnO lattice as Co2+ and substituted for Zn site with no evidence of any impurity phase, whereas inhomogeneous films of wurtzite ZnO phase mixed with cubic CoO phase formed when oxygen pressure was high. The experimental results show that the magnetic behavior is directly related to the presence of intrinsic defects. By changing oxygen pressure to control the amount of Zn vacancies, zinc interstitials and oxygen vacancies, ferromagnetism can be tuned significantly, which is a direct evidence that these defects play an important role in mediating the ferromagnetism in Co-doped ZnO thin films. [Copyright &y& Elsevier]

Icosahedra in Cu65Zr35 metallic glasses are destroyed and generated simultaneously during shear deformation. Our results show that not all icosahedra are stable. Newly created icosahedra during the deformation process are as prone as non-icosahedral atoms with low-population polyhedra to the formation of shear transformation zones (STZs). Interconnected networks have been proven to play a critical role on their response to shear strain. Icosahedra with intensive networks are resistant to STZs, while those with sparse networks are prone to STZs. [Copyright &y& Elsevier]

Abstract: The short-range order and medium-range order of ternary Zr–Cu–Al and binary Zr–Cu metallic glasses (MGs) have been investigated. When substituting a few percent of Al for Zr in the Zr–Cu alloy, the resultant ternary alloy exhibits more full icosahedra. Furthermore, the number of Zr icosahedral atoms increases significantly since Al-centred full icosahedra favours Zr as neighbour atoms. Additionally, the interconnecting networks in Zr–Cu–Al MG are enhanced significantly through intensive sharing frequencies between the full icosahedra. The reduction of isolated icosahedra in the ternary system lowers the atomic mobility and slows down the dynamics in the supercooled liquid region, which reduces theoretical cooling rate for the preparation of bulk MG. [Copyright &y& Elsevier]

Abstract: In this work, we employed classical molecular dynamics simulations to study Zr x Cu90−x Al10 metallic glasses with a wide metallic compositions ranging from 20% to 70%. Radial distribution functions were used to determine interactions between like and unlike bonds and the corresponding interatomic distances. The results showed evidence of short-range order (SRO) in Cu–Al and Al–Zr pairs. The average interatomic distance of the Cu–Al bond was observed to be shortened by 6% in all the systems studied. Analysis of coordination numbers (CNs) indicated that the total CN is nearly invariant in these systems. Finally, common neighbor analysis was conducted to determine icosahedral ordering. The result revealed that the addition of a low Al concentration to Zr–Cu alloys exhibits more prominent icosahedral ordering, except at the Zr-rich end. [Copyright &y& Elsevier]

Abstract: Molecular dynamics simulations of Al–Mg metallic glasses with a wide composition range have been conducted. We made use of a variety of analytical methods to study their amorphous structure. Pair distribution functions were constructed to determine the interatomic distances, and we found good agreement with reported simulation and experimental results. Coordination number analyses revealed that Mg atoms are more likely to serve as neighbour atoms in Al-centred icosahedral clusters in the middle concentration range or to form larger polyhedra at the Al-rich end. The presence of the 155-type pairs demonstrated that icosahedral ordering is predominant in the Al–Mg alloy. Results of Voronoi tessellation showed that Al-centred icosahedra are abundant in most compositions of the Al–Mg alloy and will lead to the formation of short-range order. The icosahedral clusters are highly shared with one another forming the medium-range order and there are less than 3% isolated icosahedra in most of the compositions of the Al–Mg alloy. Finally, the sharing schemes of icosahedra are represented by the splitting of the second peak of each pair distribution function. [Copyright &y& Elsevier]

Abstract: Raloxifene, a selective estrogen receptor modulator, has been observed to offer a neuroprotective effect in several in vitro models of neurotoxicity. An excessive release of glutamate is considered to be related to neuropathology of several neurological diseases. In this study, we investigated whether raloxifene could affect endogenous glutamate release in nerve terminals of rat cerebral cortex (synaptosomes) and explored the possible mechanism. Raloxifene exhibited a dose-dependent inhibition of 4-aminopyridine (4-AP)-evoked release of glutamate, and this effect was not blocked by the estrogen receptor antagonists. The effect of raloxifene on the evoked glutamate release was prevented by the chelating extracellular Ca2+ ions, and by the vesicular transporter inhibitor bafilomycin A1, but was insensitive to the glutamate transporter inhibitor DL-TBOA. Raloxifene decreased the depolarization-induced increase in the cytosolic free Ca2+ concentration ([Ca2+]C), whereas it did not alter the resting synaptosomal membrane potential or 4-AP-mediated depolarization. The effect of raloxifene on evoked glutamate release was prevented by blocking the Cav2.2 (N-type) and Cav2.1 (P/Q-type) channels, but not by blocking intracellular Ca2+ release or Na+/Ca2+ exchange. In addition, the inhibitory effect of raloxifene on evoked glutamate release was abolished by the mitogen-activated/extracellular signal-regulated kinase kinase (MEK) inhibitors, PD98059 and U0126. Furthermore, raloxifene significantly decreased the depolarization-induced phosphorylation of mitogen-activated protein kinase/extracellular signal-regulated kinase 1 and 2 (MAPK/ERK1/2) and synapsin I, the main presynaptic target of ERK. Thus, the effect of raloxifene on evoked glutamate release is linked to a decrease in [Ca2+]i contributed by Ca2+ entry through presynaptic voltage-dependent Ca2+ channels and to the subsequent suppression of the ERK/synapsin I signaling cascade. [Copyright &y& Elsevier]

Abstract: In the trend toward the development of electronic products that are compact and lightweight, as portable consumer electronic products, such as the cell phone, Bluetooth, GPS, W-LAN, digital camera, wireless phone, and notebook computer, increase in demand, the frequency control components needed for communications related industries receive increased attention. The crystal oscillator is widely used as a frequency selective passive component in communications related industries because of excellent characteristics, such as temperature stability and a low loss. A crystal oscillator consists mainly of a quartz crystal and an IC that controls the oscillation circuits, and is applied to high precision communications products, requiring high frequency accuracy. A crystal oscillator with an output frequency that deviates or is unstable will seriously degrade the quality and functionality of an expensive communications product. This present research investigates the crystal oscillator manufacturing processes, developing risk priority number analysis specifically for critical-to-quality processes and identifying the optimum priority for improvements in the process quality. Using Taguchi experimental design techniques the optimal parameter design is determined for quality characteristics and a mathematic programming method establishes an objective mode for monitoring quality. Lastly, the present research uses a real case to verify the modes proposed in this project, to enhance customer satisfaction, and produce crystal oscillators with a competitive advantage. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we report the electrical transport and dielectric properties of the La0.95Tb0.05MnO3/Nb-doped SrTiO3 heterojunction fabricated by laser molecular beam epitaxy. The sample shows a grain-boundary like current–voltage behavior and linear ( is capacitance) behavior in both forward and backward biases. These results are interpreted in terms of an interfacial layer which absorbs electrons from the film and substrate forming back-to-back Schottky barriers. Charge carriers trapped by the interfacial layer are found to follow an electric-field activated law. This work demonstrates the presence of the interfacial layer and indicates that this layer can play an active role in determining the properties of the heterojunction. [Copyright &y& Elsevier]

Abstract: We performed a further investigation on the Maxwell–Wagner (MW) relaxation-induced relaxor-like dielectric response characterized by a broad peak in the real part of the dielectric permittivity as a function of temperature. Based on the double-layer MW model formulated by Catalan et al. (2000) , an empirical formula was derived to describe the temperature dependence of the peak intensity. It was also found that the temperature dependence of the peak position can be characterized by an Arrhenius-like relation. The differences between the true relaxor and MW-related relaxor behaviours are also discussed. [Copyright &y& Elsevier]

Abstract: Antioxidant activity of polysaccharide fractions isolated from Lycium barbarum Linnaeus was evaluated. Polysaccharides were extracted with boiling water, followed by precipitating with ethanol, protein hydrolysis, dialysis, and fractionation with a DEAE–Sepharose CL-6B column. A total of 4 fractions, including 1 neutral polysaccharide (LBPN) and 3 acidic polysaccharides were obtained, and compared with crude polysaccharide (CP), crude extract of polysaccharide (CE), deproteinated polysaccharide (DP), and deproteinated and dialyzed polysaccharide (DDP) for antioxidative activity. With the exception of CE and DDP, most polysaccharides were effective in scavenging DPPH and ABTS + free radicals, superoxide anion and hydroxyl radical at 1000μg/mL. [Copyright &y& Elsevier]

Abstract: We present a systematic study of field-dependent evolution in the magnetization reversal process of elongated Co ring arrays using in-situ field magnetic force microscopy. We observed that, the rings typically undergo a uniform→onion→vortex→reverse onion→reverse uniform spin-state transition as the field is swept along the major axis of the rings. However, the switching field distribution in the arrays generally leads to each transition occupying a wide range of fields, which results in the observation of coexistence of different magnetization states at lower field. The magnetization reversal sequence has also been verified by micromagnetic simulations, which show good agreement with our experimental data. [Copyright &y& Elsevier]

Abstract: We report on the systematic evolution of the micromagnetism in mesoscopic Ni80Fe20 anti-structures of complex geometrical shapes such as anti-ring, anti-U and anti-C structures. By using magnetic force microscopy (MFM) techniques, we observed directly that the local magnetic spin states at remanence are strongly influenced by the anti-structure geometry and field orientation due to shape-induced magnetic anisotropy. Our experimental results are in very good agreement with micromagnetic simulations. [Copyright &y& Elsevier]

Abstract: Areca quid chewing is a major risk factor associated with oral submucous fibrosis (OSF) and oral cancer. Experimental evidence indicates that immune deterioration is associated with the pathophysiology of OSF and oral cancer. In addition, reactive oxygen species (ROS) is shown to play a role in the cytotoxic and genotoxic effect induced by areca nut extracts (ANE) in oral cells. The present studies investigated the effects of ANE on T-cell reactivity and the role of ROS in ANE effects. Treatment of splenocytes with ANE induced a marked cytotoxic effect, and suppressed the production of IL-2 and IFN-γ, whereas the production of IL-4 was unaffected. The ANE-mediated cytotoxicity, and suppression of IFN-γ and IL-2 production were attenuated by the presence of antioxidant N-acetyl-l-cysteine (NAC). Moreover, flow cytometric analysis demonstrated an increase in cellular ROS levels in splenic T-cells treated with ANE, which was also attenuated by the presence of NAC. Concordantly, the cellular level of glutathione was diminished by ANE in splenic T-cells pretreated with NAC. Collectively, these results demonstrated that ANE markedly suppressed T-cell activation and Th1 cytokine production, which was mediated, at least in part, by the induction of oxidative stress. [Copyright &y& Elsevier]

Abstract: La0.67Ba0.33MnO3–20wt.%-Ba0.7Sr0.3TiO3 composites were sintered at different temperatures in order to explore the possibility of improving the magneto-transport properties of the composites. Detail studies on the magnetic and electrical transport properties for the sintered composite samples have been performed. Results show that the sintered composites have identical ferromagnetic to paramagnetic transition temperature and filamentary feature of metallic phase. When sintering temperature higher than 1300°C, the composites show Efros–Shklovskii-like variable-range hopping in the temperature range lower than Curie temperature. For samples sintered lower than 1100°C, a dome-like resistance peak appears at a temperature well below the Curie temperature. Magnetoresistance behavior indicates the existence of spin polarized tunneling in the low temperature range. Considering the contributions from Efros–Shklovskii-like variable-range hopping and spin polarized tunneling, the resistance peak can be well fitted. [Copyright &y& Elsevier]

Abstract: This paper deals three-dimensional axisymmetric quasi-static coupled thermoelastic problems for time-dependent boundary condition. The water vapor temperature and pressure relation assumed for the inner boundary. The water vapor temperature and pressure data were obtained from a thermodynamic steam table. Laplace transform and finite difference methods are used to analyze problems. The solution is obtained by using the matrix similarity transformation and inverse Laplace transform. We obtain solutions for the temperature and thermal deformation distributions in a transient and steady state. Moreover, the computational procedures established in this thesis, can solve the generalized thermoelasticity problem for multilayered hollow cylinder with nonhomogeneous materials. [Copyright &y& Elsevier]

Abstract: CaCu3Ti4O12/Ag composites with different Ag weight fractions were prepared by sintering thoroughly mixed CaCu3Ti4O12 and Ag2O powders at 1050°C in air. The samples were found to consist of Ag-deficient insulating surface layers and Ag-rich more conductive inner parts. Dielectric measurements reveal that, apart from the distinct dielectric features for pure CaCu3Ti4O12, another dielectric relaxation appears near room temperature. This relaxation has been interpreted based on the Maxwell–Wagner model due to discontinuity of the charge concentration across the interface between the surface and inner layers. [Copyright &y& Elsevier]

Abstract: Objectives: : Our aim was to utilize publicly available and proprietary sources to discover candidate genes important for ocular development. Design and methods: : The collated information on our 5092 non-redundant clusters was grouped and functional annotation was conducted using gene ontology (FatiGO) for categorizing them with respect to molecular function. The web-based viewer technological platform (H-InvDB) was employed for transcription analyses of in-house high quality fetal eye Expressed Sequence Tags (ESTs). Eye-specific ESTs were also analyzed across species by using EMBEST. Results: : According to adult eye cDNA libraries, nucleic acid binding and cell structure/cytoskeletal protein genes were the most abundant among the ESTs of fetal eyes. Using cDNA assembly in H-InvDB, 20 (80%) of the 25 most commonly expressed genes in the human eye are also expressed in extraocular tissues. The crystalline gamma S gene is highly expressed in the eye, but not in other tissues. We used EMBEST to compare human fetal eye and octopus eye ESTs and the expression similarity was low (1.6%). This indicated that our fetal eye library contains genes necessary for the developmental process and biological function of the eye, which may not be expressed in the fully developed octopus eyes. The human fetal eye cDNA library also contained highly abundant eye tissue genes, including αA-crystallin, eukaryotic translation elongation factor 1 alpha 1 (EEF1A1), bestrophin (VMD2), cystatin C, and transforming growth factor, beta-induced (BIGH3). Conclusions: : Our annotated EST set provides a valuable resource for gene discovery and functional genomic analysis. This display will help to appreciate the strengths and weaknesses of the different technological platforms, so that in future studies the maximum amount of beneficial information can be derived from the appropriate use of each method. [Copyright &y& Elsevier]

Abstract: SiGe has been utilized for aggressive CMOS technologies development recently and there are many references [M. Shima, T. Ueno, T. Kumise, H. Shido, Y. Sakuma, S. Nakamura, Symposium on VLSI Technology Technical Digest, 2002, pp. 94–95; T. Ghani, M. Armstrong, C. Auth, M. Bost, P. Charvat, G. Glass, T. Hoffmann, K. Johnson, C. Kenyon, J. Klaus, B. McIntyre, K. Mistry, A. Murthy, J. Sandford, M. Silberstein, S. Sivakumar, P. Smith, K. Zawadzki, S. Thompson, M. Bohr, International Electron Devices Meeting Technical Digest, December 2003, pp. 978–980; P. Bai, C. Auth, S. Balakrishnan, M. Bost, R. Brain, V. Chikarmane, R. Heussner, M. Hussein, J. Hwang, D. Ingerly, R. James, J. Jeong, C. Kenyon, E. Lee, S. Lee, N. Lindert, M. Liu, Z. Ma, T. Marieb, A. Murthy, R. Nagisetty, S. Natarajan, J. Neirynck, A. Ott, C. Parker, J. Sebastian, R. Shaheed, S. Sivakumar, J. Steigerwald, S. Tyagi, C. Weber, B. Woolery, A. Yeoh, K. Zhang, M. Bohr, International Electron Devices Meeting Technical Digest, December 2004, pp. 657–660] presenting the advantages brought by it. A better understanding regarding the boron diffusion behavior within and in the vicinity of SiGe is necessary to optimize the extension and the source/drain in pMOSFET. In order to achieve the goal, both effects from mechanical strain and Ge doping on boron diffusion have been investigated. However, only a few publications discuss the impacts of both. Furthermore, most researches investigate these two effects under the conditions of low boron concentration [P. Kuo, J.L. Hoyt, J.F. Gibbons, J.E. Turner, D. Lefforge, Appl. Phys. Lett. 66 (January (5)) (1995) 580–582; N.R. Zangenberg, J. Fage-Pedersen, J. Lundsgaard Hansen, A. Nylandsted Larsen, J. Appl. Phys. 94 (September (6)) (2003) 3883–3890] and high thermal budget anneal [P. Kuo, J.L. Hoyt, J.F. Gibbons, J.E. Turner, D. Lefforge, Appl. Phys. Lett. 66 (January (5)) (1995) 580–582; N.R. Zangenberg, J. Fage-Pedersen, J. Lundsgaard Hansen, A. Nylandsted Larsen, J. Appl. Phys. 94 (September (6)) (2003) 3883–3890; S. Eguchi, C.N. Chleirigh, O.O. Olubuyide, J.L. Hoyt, Appl. Phys. Lett. 84 (January (3)) (2004) 368–370] in which the equilibrium state of point defects is achieved. These are not the conditions used in aggressive CMOS technologies. Our experiment has therefore been designed to investigate boron diffusion in both strained and strain-relaxed SiGe including ultra-low energy, high concentration boron implant and spike RTA. Models are proposed and the retardation factors corresponding to Ge concentration and stress effect were successfully extracted through these experiments. This paper describes these experiments, with the calibration and the resulting diffusion constants for an ultra-shallow boron junction in SiGe that is popular in advanced CMOS technology. [Copyright &y& Elsevier]

Abstract: Barium strontium titanate (Ba x Sr1− x TiO3, BST) films were prepared by rf magnetron sputtering with the substrate temperature ranging from 25 to 550°C and were investigated by transmission electron microscopy (TEM) equipped with an energy dispersive spectroscopy (EDS), field-emission scanning electron microscopy (FE-SEM), Auger electron spectroscopy (AES) and atomic force microscopy (AFM). Electrical characteristics of the BST was evaluated with the films deposited on the Pt/Ti/SiO2/Si multilayered substrate. It is found that the film deposited at substrate temperature 25°C is amorphous, whereas that deposited at substrate temperature 450°C is a mixture of crystalline and amorphous phases, in which small crystallites are dispersed near the surface of the film. In contrast, the film deposited at substrate temperature 550°C shows a columnar structure with 20–50nm in column size. It is likely that the crystallinity of the BST films depends upon the stoichiometric composition of the film. Measurement of electrical properties shows that the dielectric constant of BST increases with the crystallinity and grain size of the films. It is also obtained that the leakage current density is closely related to the microstructure of the BST films, but is nearly independent on the surface morphology of the films. [Copyright &y& Elsevier]

Abstract: High-density micromirror arrays (1296 mirrors) have been fabricated with a process that combines the benefits of both bulk and surface micromachining. Arrays fabricated with this technique are characterized by optically flat mirrors characterized by radius of curvature (ROC) ∼1m, spring constant uniformity (∼6%) across the array, and yields greater than 90%. Each array element consists of a mirror-in-gimbal structure that allows the mirror to rotate about two orthogonal axes when voltage is applied to electrodes beneath the mirror. A dry release process combined with through wafer etching and spin-cast polyimide is introduced as a simple, effective alternative to critical point drying for releasing the structures. Tilt angle measurements for these devices show stable angular range of ±5° (mechanical) at 160–170V. [Copyright &y& Elsevier]

The effects of 5 wt.% Ag2O addition on the structural and electrical properties of La2CuO4 (LCO) thin films have been examined. The Ag-containing films show smooth surface appearance which has been regarded as the result of the so-called rapid sequential pulsed laser deposition (RS-PLD). Fine fittings to the resistivity data indicate that pure LCO film exhibits the behavior of three-dimensional Mott variable range hopping (VRH). However, the doped film shows VRH behavior in the lower temperature range, while in higher temperature range obeys the law of ordinary thermal activation. This fact implies that Ag addition to LCO system creates strong disorder which suppresses superconductivity by means of destroying the effective coupling strength and phase coherence. [Copyright &y& Elsevier]

Abstract: Effects of Pr6O11 doping on the microstructures and the electrical properties of Bi4Ti3O12 (BIT) were investigated using dense ceramics, which were prepared by a conventional ceramic technique. For all the samples, X-ray diffraction (XRD) analyses revealed Bi-layered perovskite structures, and the scanning electron microscope (SEM) micrographs showed well developed plate-like morphologies with random orientations. The P–E hysteresis loop of samples measured at room temperature exhibited a large remnant polarization and a low coercive field. In addition, the DC current–voltage properties measured at different temperature from RT to 550 °C were discussed. Results indicate that Pr6O11 can be a good additive to improve the properties of Bi4Ti3O12. [Copyright &y& Elsevier]

Automatic inspection and classification of printed circuit board (PCB) defects remains a problem in the Integrated Circuit (IC) industry. In a small volume, large production variety environment, some of the widely used defects classification tools are the Bayes classifier, the linear discriminant function (LDF) classifier, the minimum distance classifier, and the K-nearest neighbour (K-NN) classifier. These classifiers all have shortcomings and their applications are limited. This study proposes the logistic regression tree as classifier where each node implements a logistic regression model to make a binary split, and draws a comparison with other classifiers. This experiment uses the Red-Green-Blue (RGB) values of an image with PCB golden fingers, as opposed to some features extracted from the image. The golden fingers defects considered in this study are scuffing, blotted tin, exposed nickel, and unplating. The result of this experiment shows that the logistic regression tree has an accuracy of 89.33%, while other classifiers can only achieve 81.67% to 87.17%. Furthermore, the decision flexibility and the result stability show that the logistic regression tree is an excellent choice as a classifier. [ABSTRACT FROM AUTHOR]

Polyacrylamide particles containing nanosized magnetic iron oxide were prepared via inverse miniemulsion polymerization in this paper. The particle size of magnetic polymeric particles is about 100 nm, and these particles are superparamagnetic. The relative parameters of the miniemulsion polymerization, such as the surfactant content, ultrasonicating time, Fe3O4 and N, N′-methylene bis acrylamide content, were studied in detail. The iron oxide nanoparticles were characterized by X-ray diffraction and transmission electron microscopy (TEM). The final magnetic polymeric particles were characterized by TEM, scanning electron microscopy, dynamic light scattering, magnetization analysis and thermogravimetric analysis. [Copyright &y& Elsevier]

The effects of Ag addition on the microstructural and electrical properties of sintered La2CuO4 have been studied. Unexpectedly, Ag-doped sample shows strong limitation of grain growth. The resistivity behavior of the variable range hopping was observed in the low temperature range (13–41 K) and the ordinary thermal activation process was observed in the high temperature range (41–90 K). A model was proposed to deduce the accurate transition temperature and transition range. The experimental results indicate that the addition of Ag not only increases the hole density but also creates sufficient disorder in the sample. [Copyright &y& Elsevier]

The kinetics of cadmium sorption on to tree fern has been investigated based on the assumption of a pseudo-second order rate law. The batch sorption model has been applied to predict the rate constant of sorption and the equilibrium capacity with the effect of initial cadmium concentration. The experimental results have been analysed by pseudo-Langmuir, pseudo-Freundlich and pseudo-Redlich–Peterson isotherms based on pseudo-second order kinetic expression constant. Both pseudo-Langmuir and pseudo-Redlich–Peterson isotherms were found to represent the measured sorption data well. According to the evaluation using the pseudo-Langmuir equation, the monolayer sorption capacity was obtained to he 16.3 mg/g. In addition, χ2 analysis was also used to determine the most suitable model. Pseudo-Langmuir and pseudo-Redlich–Peterson were also the best models for the experiment data from χ2 analysis. [Copyright &y& Elsevier]

La0.8MnO3 thin films without and with an insulating LaMnO3 buffer layer were prepared by pulsed laser deposition to investigate the origin of the columnar growth morphology and the effect of columnar structure on transport properties. In the La0.8MnO3 film without a buffer layer, a columnar growth morphology is observed. While in the film with a buffer layer, which reduce the mismatch between the film and the substrate, there is no columnar structure. This gives evidence that the mismatch leads to the columnar growth morphology. The magnetoresistance at 1 T increases from 31% in the film without columnar structure to 54% in the film with columnar structure. The great enhancement of magnetoresistance is attributed to the grain boundaries in the film. [Copyright &y& Elsevier]

Waste biosolids collected from sewage works is a biomass containing a vast amount of polysaccharides and proteins, and thus is considered a potential substrate for producing hydrogen using anaerobic fermentation. This work demonstrated, contrary to the common assumption, that the solids phase in waste activated biosolids presents extra nutrients for anaerobes; it in fact prohibits effective bio-hydrogen production. Using filtrate after removal of solids from biosolids produces more hydrogen than using the whole biosolids, with the former reaching a level an order of magnitude higher than the literature results. [Copyright &y& Elsevier]

Excess wastewater sludge collected from the recycling stream of an activated sludge process is biomass that contains large quantities of polysaccharides and proteins. However, relevant literature indicates that the bio-conversion of wastewater sludge to hydrogen is limited and therefore not economically feasible. This work examined the anaerobic digestion of wastewater sludge using a clostridium strain isolated from the sludge as inoculum. A much higher hydrogen yield than presented in the literature was obtained. Also, the effects of five pre-treatments—ultrasonication, acidification, sterilization, freezing/thawing and adding methanogenic inhibitor—on the production of hydrogen were examined. Freezing and thawing and sterilization increased the specific hydrogen yield by 1.5–2.5 times to that of untreated sludge, while adding an inhibitor and ultrasonication reduced the hydrogen yield. [Copyright &y& Elsevier]

SIMS was used to investigate the isoelectronic In-doped p-type GaN films. The growth rate of the p-type GaN film decreased with increasing Mg and In doping. The Mg saturation in GaN was 3.55×1019 atoms/cm3. The role of In as surfactant was evaluated by varying In concentrations and it was observed that the surface appeared smooth with increasing In incorporation. The Mg solubility in p-type GaN improved to 0.0025% molar ratio of the GaN with In incorporation. The In concentration results observed in neutron activation analysis (NAA) were found to be higher by a factor of 2.88 than that observed in SIMS and can be attributed to the difference in sensitivity of the two techniques. Good linearity in the results was observed from both techniques. [Copyright &y& Elsevier]

Purpose: Nasopharyngeal carcinoma is rare in the United States and common in southern China. Evaluating American patients treated using a uniform technique and staged with CT scanning, we determined whether Chinese and non-Chinese patients differ in presentation and outcome.Methods and Materials: Between 1979 and 1996, 172 patients treated at Massachusetts General Hospital received primary radiotherapy with curative intent for nasopharyngeal carcinoma. Forty-one patients (24%) were of Chinese descent, and 41% of cancers were classified as having lymphoepithelioma histologic features. Most patients received twice-daily radiotherapy and a brachytherapy boost, receiving a median dose of 72 Gy to the nasopharynx.Results: At the initial presentation, the Chinese patients were significantly younger, less likely to smoke, more likely to have Stage IV disease, and more likely to have cancer with lymphoepithelioma histologic features. After controlling for stage, age, histologic type, and treatment variables, Chinese patients were significantly more likely to develop distant metastases (p <0.05). Although Chinese race does not predict for local control or overall survival, a younger age, continued tobacco use, total radiation dose, and lymphoepithelioma histologic features do.Conclusion: In a large retrospective analysis of nasopharyngeal carcinoma, Chinese and non-Chinese patients differed significantly in presentation—age, stage, and histologic features—and outcome. We suggest as an explanation differences in intrinsic tumor biology rather than differences in treatment techniques or staging systems. Additional trials in endemic countries are needed to confirm the optimal treatment of Chinese and Chinese-American patients. [Copyright &y& Elsevier]