Gas chromatography screening of bioactive phytosterols from mono-cultivar olive oils

Phytosterols (PS) from nine samples of olive oil from Olea europaea L., the Carolea, Cassanese and Coratina mono-cultivars, have been analyzed by gas chromatography. Coratina virgin olive oil (VOO) from the month of November showed highest contents of β-sitosterol (5491 mg kg⁻¹) and Δ⁵ avenasterol (1767 mg kg⁻¹). Olive pomace oil had the lowest total content of all PS, when compared to VOO. These results suggests that, PS can be an important regulatory factor for the functional quality of olive oil along the agro-industry chain from the orchard to nutraceutical.     

Analysis and Design of Vibration Isolation System Using Open Trenches

Field vibration tests were carried out at a proposed site for the vibration testing room, and 2D numerical analysis using finite difference tool FLAC 5.0 was performed to suggest effective vibration isolation systems. In the analysis, the numerical model is first calibrated with respect to material properties, damping value, and boundary conditions to obtain the output comparable to the field test results. The calibrated model was further used to perform a parametric study by (1)?providing vibrating input motions from vibrating machines to be operated; (2)?using two depths of cutoff trench; and (3)?providing gravel bed, gravel bed with rubber pad, and gravel bed with rubber pad and cutoff trench to study the isolation effects. Comparing the results from the parametric studies with the human perception level of vibration, a decision on the isolation system was determined.     

Preparation and characterization of NiFe2O4 nanoparticles

Ni-Ferrite (NiFe₂O₄) nanoparticles haves been synthesized by simple and low cost co-precipitation technique. The synthesized product was characterized by X-ray diffraction (XRD), High resolution scanning electron microscopy (HRSEM) and vibrating sample magnetometry (VSM). The XRD and HRSEM results showed that the average particle size of the synthesized product was 20–25 nm with inverse spinel structure. The morphology of as synthesized product was in spherical shape. The existence of ferromagnetic properties was confirmed by VSM.     

Characterization of MHz pulse repetition rate femtosecond laser-irradiated gold-coated silicon surfaces

In this study, MHz pulse repetition rate femtosecond laser-irradiated gold-coated silicon surfaces under ambient condition were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS). The radiation fluence used was 0.5 J/cm² at a pulse repetition rate of 25 MHz with 1 ms interaction time. SEM analysis of the irradiated surfaces showed self-assembled intermingled weblike nanofibrous structure in and around the laser-irradiated spots. Further TEM investigation on this nanostructure revealed that the nanofibrous structure is formed due to aggregation of Au-Si/Si nanoparticles. The XRD peaks at 32.2°, 39.7°, and 62.5° were identified as (200), (211), and (321) reflections, respectively, corresponding to gold silicide. In addition, the observed chemical shift of Au 4f and Si 2p lines in XPS spectrum of the irradiated surface illustrated the presence of gold silicide at the irradiated surface. The generation of Si/Au-Si alloy fibrous nanoparticles aggregate is explained by the nucleation and subsequent condensation of vapor in the plasma plume during irradiation and expulsion of molten material due to high plasma pressure.     

Efficient catalytic epoxidation of olefins with hierarchical mesoporous TS-1 using TBHP as an oxidant

A series of hierarchical mesoporous TS-1 zeolites with MFI structure were successfully synthesized via hydrothermal route using amphiphilic organosilanes as pore directing templates. These materials were characterized by nitrogen sorption (for surface area, pore volume and pore size distribution), FTIR, SEM and UV–Visible spectroscopy. These materials are efficient catalysts for liquid phase epoxidation of olefins using TBHP as the oxidant. All these TS-1 samples oxidized cyclohexene selectively into epoxide. For the TS-1 sample with 4.4 % Ti complete conversion of cyclohexene into epoxide was observed.     

Biological Control of Rambutan Post-Harvest Anthracnose (Colleotrichum gloeosporioides) by Combined Treatment of Trichoderma harzianum-TrH40 Culture Filtrates and Calcium Salts

Trichoderma harzianum-TrH40 isolated from soil samples from rambutan (Nephelium lappaceum) orchards had antagonistic effects with combination of CaCl₂ salts on growth, activity, and infection of rambutan fruits by anthracnose (Colleotrichum gloeosporioides). Lower growth rate of spore germination, radial mycelial growth, and infectivity of anthracnose pathogen was observed at higher molar concentration of CaCl₂ by in vitro studies. Germination rate was 0.5%?when 1M CaCl₂ was combined with T. harzianum-TrH40 spore suspension. The disease incidence and severity of anthracnose were least on wounded fruits that had been dipped in a solution containing of 1,100 mg of CaCl₂ per liter and T. harzianum-TrH40, which contained 10⁶ spores/ml. Furthermore, disease incidence and severity with combined treatments were correlated significantly and effectively reduced infection in vivo in rambutan fruits.     

Nanoparticles of Pt/HxMoO3 electrodeposited in poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) as the electrocatalyst for methanol oxidation

Nanoparticles of platinum and hydrous molybdenum oxide (Pt/H_xMoO₃) were successfully electrodeposited onto poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT-PSS) film by chronocoulometry (0.2 C). Various loadings of Pt/H_xMoO₃ particles onto the PEDOT-PSS electrode were achieved using the co-deposition technique. The existence of Pt/H_xMoO₃ particles was determined through characterization by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis. XPS results revealed that deposited Pt and molybdenum were metallic Pt and H_xMoO₃, respectively. XRD analysis showed a decrease of Pt crystalline facets for the incorporation of H_xMoO₃ into PEDOT-PSS-Pt, indicating a strong interaction between Pt and H_xMoO₃. Scanning electron microscopy (SEM) results revealed a uniform dispersion of Pt/H_xMoO₃ particles, with the particle size of 70–90 nm, in the PEDOT-PSS matrix. The cyclic voltammetry study and chronopotentiometry measurements demonstrated that the PEDOT-PSS-Pt/H_xMoO₃ electrode had superior electrocatalytic activity of methanol oxidation with less CO poisoning. The presence of amorphous H_xMoO₃ particles on the Pt surface minimized CO poisoning of methanol oxidation.     

On the development of an apatitic calcium phosphate bone cement

Development of an apatitic calcium phosphate bone cement is reported. 100 μ Particles of tetracalcium phosphate (TTCP) and dicalcium phosphate dihydrate (DCPD) were mixed in equimolar ratio to form the cement powder. The wetting medium used was distilled water with Na₂HPO₄ as accelerator to manipulate the setting time. The cement powder, on wetting with the medium, formed a workable putty. The setting times of the putty were measured using a Vicat type apparatus and the compressive strength was determined with a Universal Testing Machine. The nature of the precipitated cement was analyzed through X-ray diffraction (XRD), fourier transform infrared spectrometry (FTIR) and energy dispersive electron microprobe (EDAX). The results showed the phase to be apatitic with a calcium-to-phosphorous ratio close to that of hydroxyapatite. The microstructure analysis using scanning electron microscopy (SEM) showed hydroxyapatite nano-crystallite growth over particulate matrix surface. The structure has an apparent porosity of ∼ 52%. There were no appreciable dimensional or thermal changes during setting. The cement passed the in vitro toxicological screening (cytotoxicity and haemolysis) tests. Optimization of the cement was done by manipulating the accelerator concentration so that the setting time, hardening time and the compressive strength had clinically relevant values.     

Temperature and Stress Distributions in a Hollow Cylinder of Functionally Graded Material: The Case of Temperature-Independent Material Properties

We have presented a numerical technique for analyzing one-dimensional transient temperature distributions in a circular hollow cylinder that was composed of functionally graded ceramic–metal-based materials, without considering the temperature-dependent material properties. The functionally graded material (FGM) cylinder was assumed to be initially in a steady state of gradient temperature; the ceramic inner surface was exposed to high temperature, and the metallic outer surface, which was associated with its in-service performance, was exposed to low temperature. Then, the FGM cylinder was cooled rapidly on the ceramic surface of the cylinder, using a cold medium. The transient temperature and related thermal stresses in the FGM cylinder were analyzed numerically for a model of the mullite–molybdenum FGM system. The technique for analyzing the temperature distribution is quite simple and widely applicable for various boundary conditions of FGMs, in comparison with methods that have been proposed recently by other researchers.     

Galactose concentration in pizza cheese prepared by three different culture techniques

A study was conducted to determine the most suitable lactic culture combinations and the techniques for the preparation of low moisture part skim (LMPS) mozzarella cheese (pizza cheese) with a low level of galactose. The cheesemaking time tested for all 12 culture combinations was less than 3 h and hence was found suitable for pizza cheesemaking. The initial accumulated galactose concentration was lower in unstretched curd followed by no-brine curd and stretched curd in ascending order. During storage of the cheese for 7 days, the galactose percentage in the cheeses prepared using cultures comprising galactose-fermenting strains of Lactobacillus helveticus and Streptococcus thermophilus was 0.30 in stretched curd, 0.04 in unstretched curd and 0.03 in no-brine curd. The degree of reduction in the level of galactose in pizza cheese during storage was maximum with the no-brine curd technique followed by the unstretched and stretched curd techniques in that order. This study provides information regarding selection of starter culture combinations and techniques for pizza cheesemaking based on consumer preference for low or moderate browning mozzarella cheese as a result of its galactose concentration.