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Examines the initial kinetics of surface-energy-driven grain growth (SEDGG) in silicon that occurred during rapid thermal annealing. Description of the SEDGG; Fraction of the area of a thin film transformed to secondary grains; Definition of extended fraction.

Deals with a study which investigated the mechanical properties of nanocomposite Ag-Al[sub2]O[sub3] and Fe-SiO[sub2] granular metal films by low-load indentation and laser ultrasonic methods. Film preparation and microstructural analysis; Mechanical testing methods; Results and discussion.

Presents a study on the mechanical properties of silver-Al[sub2]O[sub3] and nickel (Ni)-Al[sub2]O[sub3] granular metal thin films as well as the magnetic behavior of the Ni-based films. Enhancements in the mechanical properties of the materials; Hardness behavior of Ni-Al[sub2]O[sub3] films; Results concerning the magnetic ordering temperature of the samples.

Background: Severe obesity is a major worldwide public health concern affecting 0.5–5% of the adult population. Adiponectin (Acpr30), an adipokine secreted from adipocytes, shows pleiotropic beneficial effects on obesity and related disorders. In this study, sequence analysis of Acpr30 gene (ACDC) was performed in a highly selected population of severely obese young adult patients from Southern Italy to investigate the associations between polymorphisms in the ACDC gene and the development of severe obesity concomitantly with other features of the metabolic syndrome. Methods: The ACDC gene was analyzed by direct sequencing in the severely obese patients (n = 220) and compared to healthy controls (n = 116). The associations between the ACDC gene single-nucleotide polymorphisms (SNPs) and the levels of serum Acpr30 as well as the correlation with the presence of severe obesity jointly associated with other features of the metabolic syndrome were also investigated. Total serum Acpr30 concentrations were measured by the ELISA method. Results: ACDC gene molecular screening revealed the presence of previously described SNPs and a new nucleotide alteration, c.355T>G, leading to a protein variant, p.L119V. Measurement of serum concentration of Acpr30 demonstrated lower levels of Acpr30 in the obese population compared to controls (30.5 ± 28.3 vs. 43.9 ± 35.7 μg/ml, p < 0.01); in particular, significantly lower Acpr30 concentrations were observed in obese patients bearing c.–11377C>G SNP CG+GG genotypes than in those with CC genotype (22.9 ± 20.5 vs. 33.1 ± 29.4 μg/ml, p < 0.05). Conclusions: Our results confirmed that low serum levels of Acpr30 are related to severe obesity and a difference in protein expression is associated with variants in ACDC gene promoter region. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Gibbs formulated a complete and general thermodynamics for surfaces in multicomponent fluid systems. When considering solid-fluid surfaces, he restricted attention to single-component solids in contact with fluids that could contain multiple components. Attempts that have been offered to generalize Gibbs' results for surfaces between multicomponent solids and fluid are problematic owing to the difficulty that the surface chemical potentials for components that also reside on substitutional lattice sites in the solids are not well defined. Therefore any expressions involving these surface chemical potentials, such as the conventional definition of the surface energy, will also not be well defined. In order to formulate a general thermodynamics of equilibrium that takes into account capillary effects in systems containing surfaces between a multicomponent solids and fluids, it is shown that the concept of thermodynamic availability (exergy) can be employed that, when applied to surfaces, depends on the extensive but not the intensive variables (such as the chemical potentials) of the surfaces. Using this approach, Gibbs-Thomson-Freundlich effects for finite-size solids, an adsorption equation for solid-fluid surfaces and the thermodynamics of nucleation during solidification can be treated in a straightforward manner without referring to the ill-defined surface chemical potentials. A derivation is given that appears to be the first one that properly generalizes Gibbs' analysis for the reversible work to form a critical nucleus to the case of solidification. [ABSTRACT FROM AUTHOR]

Presents a study that developed the mechanics of thin film epitaxy using an equilibrium thermodynamics formalism and linear elasticity. Discussion on the issues involved in determining the equilibrium coherency stress and strain states of the film; Presentation of the thermodynamic system; Conditions for equilibrium; Assessment of critical film thickness.

We describe a method of precision transport of nanowires in suspension using a combination of dielectrophoretic force and electrophoretic force, which, respectively, aligns and transports the nanowires. The transport of nanowires can be made to follow any prescribed trajectory with any orientation by the voltages applied to the patterned electrodes. The same method applies to multiwall carbon nanotubes as well. We have joined end to end two oppositely charged nanowires separated by 200 μm into a microelectromechanical device. [ABSTRACT FROM AUTHOR]

The mechanical properties of multilayered Cu-Ni thin films with bilayer thicknesses of 1.6–12 nm were investigated by a nanoindentation technique. Force-displacement curves generated during loading and unloading of a diamond tip indenter were used to determine the hardness and elastic properties of the films. No enhancement in the elastic properties (supermodulus effect) was seen, but an enhancement in the hardness was observed. It is suggested that the enhancement, which displayed a Hall–Petch-type behavior, can be understood as owing to dislocation pinning at the interfaces analogous to the mechanism of grain boundary hardening. [ABSTRACT FROM AUTHOR]

We report on the formation of nickel silicide in nickel-implanted amorphous silicon thin films. We have found that during annealing, precipitates of NiSi2 form in the interior of the film. This is in contrast with results for interfacial reactions between nickel films and silicon, where the first phases to appear are Ni2Si and NiSi on amorphous silicon, and Ni2Si on crystalline silicon. We suggest that these results reflect differences in surface energies and their effects on silicide nucleation. [ABSTRACT FROM AUTHOR]

Magnetic nano-network structure has been fabricated by electrochemical deposition Ni onto laser modified Au film. Scanning electron microscopy images show that the network has a three-dimensional interconnecting branch structure with branch diameter of about 100 nm, constructed from grains with diameter of about 25 nm. Because of this structure, the Ni network has enhanced coercivity, in-plane isotropy, and a combination of longitudinal and transverse anisotropic magnetoresistance. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

An analysis of the critical thickness dependence on misfit for epitaxy is presented including effects due to surface stresses. It is shown that these surface stress effects, which have not been included in previous theories of epitaxy, can have a major influence on the critical thickness, especially for relatively large misfits. A simple model incorporating effects due to compressive surface stresses is given which, compared to previous theories, predicts significantly larger (smaller) critical thicknesses when the stress-free lattice parameter of the film is greater (less) than the lattice parameter of the substrate. [ABSTRACT FROM AUTHOR]

Hiperco[sup ®] FeCoV alloys are soft magnetic materials suitable for applications at high temperatures and under high stresses. We have studied the evolution of the rolling texture and its effects on the mechanical and magnetic properties after annealing the Hiperco[sup ®] sheets at high temperatures. X-ray pole-figure measurements reveal that the main texture of the as-rolled HA50HS and HA50 sheets is {001}<11¯0>. This rolling texture causes the mechanical and magnetic properties to exhibit a uniaxial anisotropy, which is reduced by annealing. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The authors report a versatile and efficient method for assembling nanowires in suspension into scaffolds using ac electric fields. The electric field and its gradient aligns and transports, respectively, the nanowires into scaffolds according to the electric field distributions. The assembling efficiency strongly depends on the frequency of the applied ac voltages and varies as square of the voltage. The assembly morphology is highly influenced by the frequency regardless of applied voltages. [ABSTRACT FROM AUTHOR]

The epitaxial growth of InAs nanowires on an InAs(111) substrate in a sealed quartz tube is described. The method is quite simple and fast, and uses only a bare InAs substrate and a gold colloid coated InAs(111) substrate. High quality InAs nanowires can be produced by this technique, with the nanowire diameter controllable by the variation of growth temperature. The composition of the seed particle at the tip of the nanowire indicates that the nanowires grew via the vapor-liquid-solid growth mechanism but with Au–In as the liquid alloy. [ABSTRACT FROM AUTHOR]

We report on the use of differential scanning calorimetry to study the temperatures and kinetics of nickel silicide formation from nickel/amorphous silicon multilayer films. When the layer thickness ratio of a multilayer film is 1:1, Ni2 Si is the only phase to form. The activation energy for this reaction is 1.5 eV and the interdiffusivity pre-exponential is found to be 6 cm-2s-1. These values are in excellent agreement with values obtained using different techniques. The temperature at which Ni2 Si formation is observed a function of layer thickness, with the thinner layers reacting at lower temperatures. This layer thickness dependence can be explained by the lower reaction times for thinner layers. Upon mechanical impact, films composed of very thin layers (<125 Å) reacted explosively at room temperature to form Ni2 Si. Explosive silicidation is presumed to occur when the rate of heat generation at the many reacting interfaces exceeds the rate of heat dissipation. [ABSTRACT FROM AUTHOR]

Presents information on a study that discovered that the apparent expansivity of nickel/copper multilayers was found to depend on the interface densities in the multilayers. Experimental techniques; Results of the study; Conclusion.

Hiperco®50 alloy heat treated between 450 and 650 °C exhibits superior mechanical properties. We report the measurements of the ac core loss at various frequencies up to 4500 Hz of the Hiperco®50 alloy samples annealed at 450 and 650 °C. The 650 °C annealed specimens have lower ac core loss than that of the 450 °C annealed ones. The total core loss, consisting of contributions from hysteresis core loss and eddy-current core loss, depends on frequency f as af+bf [SUP2]. The eddy-current loss of a single laminate is minor compared to the hysteresis loss. [ABSTRACT FROM AUTHOR]

A correction to the article "Efficiency of assembling of nanowires in suspension by AC electric fields" that was published in previous issue is presented.

Presents a letter to the editor concerning negative surface energy.

A new method is presented which circumvents the usual thermodynamic limitations (alloying and compound formation) in fabricating phase-separated materials. This opens whole new classes of materials that can be prepared as particulate composites.This method utilizes sputtering at high pressures (0.2–0.6 Torr) in a thermal gradient to produce nanoscale (<15 nm diameter) particles, which are then embedded in a matrix produced by normal sputtering. The microstructure and microhardness of 0.5-μm-thick composites of molybdenum particles (3–12 nm average particle size) in aluminum are presented as examples. This system cannot be prepared by the conventional phase separation technique of cosputtering. [ABSTRACT FROM AUTHOR]

Angiotensin II receptor blockers represent a class of effective and well tolerated orally active antihyperten-sive drugs. Activation of AT[SUB1] receptors leads to vasoconstriction, stimulation of the release of cat-echolamines and antidiuretic hormone and promote growth of vascular and cardiac muscle. AT[SUB1] receptor blockers antagonise all those effects. Losartan was the first drug of this class marketed, shortly followed by val-sartan, irbesartan, telmisartan, candesartan, eprosartan and others on current investigation. All these drugs have the common properties of blockading the AT[SUB1] receptor thereby relaxing vascular smooth muscle, increase salt excretion, decrease cellular hypertrophy and induce antihypertensive effect without modifying heart rate or cardiac output. Most of the AT[SUB1] receptor blockers in use controlled blood pressure during the 24 h with a once-daily dose, without evidence of producing tolerance to the antihypertensive effect and being with low incidence of side effects even at long term use. Monotherapy in mild-to-moderate hypertension controls blood pressure in 40 to 50% of these patients; when a low dose of thiazide diuretic is added, 60-70% of patients are controlled. The efficacy is similar to angio-tensin-converting enzyme (ACE) inhibitors, diuretics, calcium antagonists and beta-blocking agents. AT[SUB1] receptor blockers are specially indicated in patients with hypertension who are being treated with ACE inhibitors and developed side effects such as, cough or angio-edema. The final position in the antihypertensive therapy in this special population and other clinical situations, such as left ventricular hypertrophy, heart failure, diabetes mellitus and renal disease, has to be determined in large prospective clinical trials, some of which are now being conducted and seem promising. [ABSTRACT FROM AUTHOR]