Effect of Graded Dispersion of SiC Particles on Dielectric Behavior of SiC/Epoxy Composite

Silicon - Gradient structures mainly boost the dielectric and mechanical properties of composites. Herein, the fabrication of silicon carbide (SiC)/epoxy gradient composites via centrifugal casting...     

Recycling of waste PET‐bottles using dimethyl sulfoxide and hydrotalcite catalyst

The degradation of PET bottles has been successfully achieved using hydrotalcite as catalyst and dimethyl sulfoxide (DMSO) as solvent. The reaction was carried out at boiling point of DMSO (190°C) and degradation was complete in 10 min. The oligomer (tetramer) obtained was treated with NaOH at room temperature in methanol to get dimethyl terephthalate (DMT) and ethylene glycol (EG). Thus, it is a safe and cleaner process. Oligomer was characterized by MS, 13 C‐NMR, X‐ray diffractometric, and thermogravimetric analysis. DMT and EG were characterized by GC‐MS. DMT was also characterized by FT‐IR. GC‐MS analysis shows that the purity of DMT was 99%. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012     

Effect of preparation and storage of khoa on physicochemical properties of milk fat

The changes in milk fat during the preparation and storage of khoa were studied in three different seasons. Milk fat was extracted from the samples with chloroform using Soxhlet extraction. The solvent was evaporated using a vacuum evaporator followed by nitrogen flushing. The extracted fat samples were analysed for Reichert–Meissl, Polenske, saponification and iodine values, butyro‐refractometer reading at 40 °C and free fatty acids (FFAs). The study revealed an increase in the FFA content during conversion and storage of khoa, while there were small changes in other physicochemical properties of milk fat during the preparation of khoa from raw milk and its subsequent storage at room temperature.     

Thermal injury and recovery of Salmonella enterica serovar enteritidis in ground chicken with temperature, pH, and sodium chloride as controlling factors

Cells of Salmonella enterica serovar Enteritidis were grown at 25 and 35 degrees C, heat injured (55, 60, and 62.5 degrees C), and recovered in tryptic soy broth (TSB) at various NaCl concentrations (2.0 and 3.5%) and pH levels (5.5 and 6.5). To assess the interactions of growth temperature, heating temperature, NaCl concentration and pH on the thermal injury and recovery of Salmonella Enteritidis in ground chicken, a randomized design with each experimental combination was used. When a logistic equation for nonlinear survival curves was used, D-values of cells of Salmonella Enteritidis grown at 25 degrees C were 7.60, 5.73, and 4.81 min at 55, 60, and 62.5 degrees C, respectively. For cells grown at 35 degrees C, the D-values were 12.38, 7.45, and 5.70 min at 55, 60, and 62.5 degrees C. The influence of tryptic soy agar and double modified lysine agar (DMLIA) on the recovery of heat-injured cells was determined. Recovery was significantly reduced on DMLIA at increased pH levels and NaCl concentrations. Higher numbers of cells were recovered in TSB with 2.0% NaCl than in TSB with 3.5% NaCl. It was observed that the rate of recovery of heat-injured cells was similar at each pH. Therefore, a pH range of 5.5 to 6.5 does not have a major inhibitory effect on the recovery of Salmonella Enteritidis.     

Spectroscopic ellipsometry investigations of the optical properties of manganese doped bismuth vanadate thin films

The optical properties of Bi₂V_1−xMn_xO_5.5−x {x = 0.05, 0.1, 0.15 and 0.2 at.%} thin films fabricated by pulsed laser deposition on platinized silicon substrates were studied in UV-visible spectral region (1.51-4.17 eV) using spectroscopic ellipsometry. The optical constants and thicknesses of these films have been obtained by fitting the ellipsometric data (Ψ and Δ) using a multilayer four-phase model system and a relaxed Lorentz oscillator dispersion relation. The surface roughness and film thickness obtained by spectroscopic ellipsometry were found to be consistent with the results obtained by atomic force and scanning electron microscopy. The refractive index measured at 650 nm does not show any marginal increase with Mn content. Further, the extinction coefficient does not show much decrease with increasing Mn content. An increase in optical band gap energy from 2.52 to 2.77 eV with increasing Mn content from x = 0.05 to 0.15 was attributed to the increase in oxygen ion vacancy disorder.     

Exponential error bounds for an erasure scheme for partial received information

The problem of coding for making decisions on the basis of a part of the received message has recently been studied. By extension of this idea, exponential error and erasure bounds are obtained.     

The effect of water on the critical stress intensity factor of unsaturated polyester resins

The effect of water on the critical stress intensity factor,K _IC, of a highly unsaturated isophthalic polyester resin has been measured for periods of immersion of up to 2200 h in water at temperatures of 35, 70 and 80° C.K _IC decreased from 0.84±0.1 MN m^–3/2 to 0.24±0.03 MN m^–3/2 after immersion for 2200 h in water at 80° C. The observed changes in the critical stress intensity factor indicate that a constant value is eventually reached. This is consistent with the decline being attributable to the leaching of extractable matter from the polyester resin.     

Development and characterization of two-transducer imaging acousto-optic tunable filters with extended tuning range

We developed two high-quality large-aperture acousto-optic tunable filter cells in TeO2 with more than two octaves spectral coverage for hyperspectral imaging applications from the visible to the midwave infrared: the first cell covers from 0.43 to 2.1 microm and the second from 0.69 to 4.0 microm. The key feature of these cells is a special design of two transducers in tandem with a special bonding technique that results in such a wide spectral coverage with virtually no acoustic and electrical loss due to careful matching of both acoustic and electrical impedances. Each of these cells has high spectral transmission, as well as low power requirement. We discuss the design, characterization, and performance results for these cells.     

Acousto-optic tunable filter imaging spectrometer with full Stokes polarimetric capability

Polarization is an important addition to spectral imaging in detecting and identifying objects of interest, and simple linear polarization measurements are often inadequate. Full polarization analysis can give additional information for discrimination where the polarization state is completely described by the Stokes parameters. An acousto-optic tunable filter (AOTF) imaging system was built incorporating two liquid-crystal variable retarders (LCVRs) that can provide complete spectral-polarimetric analysis, and it is believed to be the first demonstration of a full Stokes polarimetric AOTF spectral imaging system with no moving parts. It is also shown that a single LCVR cannot provide all the Stokes parameters.     

Stress Alleviation and Crop Improvement Using Silicon Nanoparticles in Agriculture: a Review

Silicon - Silicon (Si) is not considered as essential element for plant growth and development but it provides benefits to the plants in several ways. Due to distinguishing physiological features,...