On the qualitative behaviors of solutions of third order nonlinear differential equations

We present some new results about oscillation and asymptotic behavior of solutions of third order nonlinear differential equations of the form

(r₂(t)(r₁(t)y^′)^′)^′+p(t)y^′+q(t)f(y(g(t)))=0.     

Synthesis and Characterization of Ferromagnetic Nickel Nanoparticles

Nickel nanoparticles on mass production scale have been prepared using a modified polyol process with Ni(CH₃COO)₂?4H₂O, NaOH, 1,2 propandiol and hydrazinium hydroxide (N₂H₄?H₂O). A?mixture of face centered cubic (fcc) metallic nickel nanoparticles with 12 nm diameter were obtained. We have experimentally studied the structure of nanoparticle by X-ray and Scanning Electron Microscopy (SEM, EDS). The magnetic properties of the prepared Ni film have been studied by Ferromagnetic Resonance (FMR) technique, Vibrating Sample Magnetometer (VSM) and Vector Network Analyzer (VNA). The effective g-factor and magnetic anisotropy constant were determined as g _eff=2.25 and K _eff=85?Oe, respectively.     

Influence of weak organic acids and salts on the denaturation characteristics of intramuscular connective tissue. A differential scanning calorimetry study

Intramuscular connective tissue obtained from Longissimus dorsi muscle of a 4-year-old beef carcass was treated with NaCl solutions of 2, 4, and 6% (w/v), and CaCl₂ solutions of 50, 100, and 150 mM, and citric and lactic acid solutions of 0.5, 1.0, and 1.5% for three different marinating periods (24, 46, and 72 h). Changes in denaturation characteristics were investigated using differential scanning calorimetry and it was found that the denaturation onset temperature (T_o) and the denaturation peak temperature (T_p) increased as the NaCl concentration increased but decreased as the CaCl₂ concentration increased, irrespective of marinating time. Lactic and citric acid decreased T_o to about 39°C, from over 60°C breaking the structure of fibrils.     

Moisture adsorption isotherms and thermodynamics properties of sucuk (Turkish dry-fermented sausage)

Moisture adsorption isotherms of sucuk were determined using the isopiestic method at 10 °C, 20 °C and 30 °C and within the range of 0.2-0.9 water activity. The isotherms of sucuk exhibited Type II behavior according to BET classification. The adsorption data were analyzed using mathematical equations of Halsey, Caurie, Peleg, Smith, Oswin, Henderson, Modified-BET, GAB, Ferro-Fontan and Harkins-Jura. The best fit of experimental data was obtained with Peleg equation in the range of temperatures and water activities investigated. Thermodynamic properties such as differential enthalpy and entropy, enthalpy-entropy compensation, spreading pressure, net integral enthalpy and entropy were determined from moisture adsorption isotherm data of sucuk. The net isosteric heat of sorption and differential entropy decreased with increasing moisture contents in an exponential function. The spreading pressure increased with increasing water activity, and decreased with increasing temperature. The net integral enthalpy decreased with increased moisture content. The integral entropy increased with moisture content, but it was negative in value. The enthalpy-entropy compensation theory was applied to water adsorption of sucuk.     

Modifying of Cotton Fabric Surface with Nano-ZnO Multilayer Films by Layer-by-Layer Deposition Method

ZnO nanoparticle–based multilayer nanocomposite films were fabricated on cationized woven cotton fabrics via layer-by-layer molecular self-assembly technique. For cationic surface charge, cotton fabrics were pretreated with 2,3-epoxypropyltrimethylammonium chloride (EP3MAC) by pad-batch method. XPS and SEM were used to examine the deposited nano-ZnO multilayer films on the cotton fabrics. The nano-ZnO films deposited on cotton fabrics exhibited excellent antimicrobial activity against Staphylococcus aureus bacteria. The results also showed that the coated fabrics with nano-ZnO multilayer films enhanced the protection of cotton fabrics from UV radiation. Physical tests (tensile strength of weft and warp yarns, air permeability and whiteness values) were performed on the fabrics before and after the treatment with ZnO nanoparticles to evaluate the effect of layer-by-layer (LbL) process on cotton fabrics properties.     

Molecular dynamics simulation of compressible hot/cold moving lid-driven microcavity flow

Hard-sphere molecular dynamics simulations of lid-driven microcavity gas flow with various subsonic speeds and lid temperatures are conducted. Simulations with faster and colder lids show streamlines of stronger primary vortices. Variations of mass and energy centers with respect to lid speed and temperature are examined. Center of energy is less sensitive to employed lid conditions than center of gravity is. Although moving lid imparts energy into fluid, due to change of impingement rates on the walls of fixed temperature, average energy within the cavity seems quite insensitive to the subsonic lid speed. Behavior of compressibility at both top corners is observed even at low Mach numbers widely considered within incompressible flow region. While high Knudsen number causes considerable property slips near the lid, two-dimensional pressure, density, and temperature plots of excellent quality are generated. Results are promising in use of molecular dynamics simulations for compressible vortex flow analyses while providing insights for understanding microfluidics and nanofluidics in context of molecular mass, momentum and heat transfer in microscale and nanoscale systems.