Spectral studies on CuO in sodium–calcium borophosphate glasses

Transparent borophosphate glasses doped with CuO were prepared by melt quenching technique. X-ray diffraction (XRD), optical and luminescence properties of sodium–calcium borophosphate glasses doped with CuO have been studied. The XRD results showed the amorphous nature of the sample. The introduction of CuO was favourable for the colour changes from light blue to dark bluish green colour. Direct optical energy bandgaps before and after doping with different percents of copper oxide obtained in the range 4.81–2.99 eV indicated the role of copper in the glassy matrix by ultraviolet (UV) spectra. The glasses have more than 80% transparency for emission wavelength range, and strong absorption bands due to the charge transition of the Cu⁺ and Cu²⁺ ions were observed. The emission bands observed in the UV and blue regions are attributed to 3d⁹4s–3d¹⁰ triplet transition in Cu⁺ ion.     

Tocopherols, Retinol and Carotenes in Chicken Egg and Tissues as Influenced by Dietary Palm Oil

Incorporation of palm oil (PO) increased the α-and γ-tocotrienol content of eggs, liver, meat and adipose tissue. Total tocotrienols were higher in eggs, liver and adipose tissue of hens fed 1.5% PO than those fed 3.5% PO. An increase in retinol was observed in the eggs, liver and dark meat of hens fed PO diet. Feeding diets containing 1.5 or 3.5% PO increased the α-and β- carotenes in eggs and liver tissue. However, carotenoids were not detected in white meat, dark meat or adipose tissue. Dark meat incorporated higher levels of tocopherols and retinol than white meat. The diets had no effect on egg or yolk weight. Egg yolks from hens fed PO had higher yolk color than those without PO. Addition of tocopherol mix in the control diet increased total tocopherol content in all tissues.     

Comparative evaluation of tungsten inert gas and laser beam welding of AA5083-H321

In this study, the bead-on-plate welds were made on AA5083-H321 alloy plates using both tungsten inert gas (TIG) welding and laser beam (LB) welding processes to study the enhancement of mechanical properties such as weld yield strength and hardness. The low heat input of laser beam welding effectively reduced the size of the fusion zone and heat affected zone compared to tungsten inert gas welding process. High speed LB welding and fast heating and cooling of LB welding process hinders grain growth compared to TIG welding process. The effect of vapourization of volatile alloying elements is also considered. It seems that magnesium evaporation is relatively less in LB welding compared to TIG welding. Tensile testing of the welded joints revealed that LB welding results in superior mechanical properties. It is concluded that LB welding process is more suitable to join AA5083-H321.     

A new universal gate for low power SoC applications

This paper formulates a new design technique for an area and energy efficient Universal NAND gate. The proposed robust three transistors (3T) based NAND gate is just as effective for dynamic power control in CMOS VLSI circuits for System on Chip (SoC) applications. The 3T NAND gate is intuitively momentous and lead to better performance measures in terms of dynamic power, reduced area and high speed while maintaining comparable performance than the other available NAND gate logic structures. Simulation tests were performed by employing standard Berkeley Predictive Technology Model (BPTM) 22 nm, 45 nm and 90 nm process technologies. The experiment and simulation results show that, the proposed 3T NAND gate effectively outperforms the basic CMOS NAND gate with excellent driving capability and signal integrity with exact output logic levels.     

Design of multi-layer anti-reflection coating for terrestrial solar panel glass

To date, there is no ideal anti-reflection (AR) coating available on solar glass which can effectively transmit the incident light within the visible wavelength range. However, there is a need to develop multifunctional coating with superior anti-reflection properties and self-cleaning ability meant to be used for solar glass panels. In spite of self-cleaning ability of materials like TiO₂ and ZnO, these coatings on glass substrate have tendency to reduce light transmission due to their high refractive indices than glass. Thus, to infuse the anti-reflective property, a low refractive index, SiO₂ layer needs to be used in conjunction with TiO₂ and ZnO layers. In such case, the optimization of individual layer thickness is crucial to achieve maximum transmittance of the visible light. In the present study, we propose an omni-directional anti-reflection coating design for the visible spectral wavelength range of 400–700 nm, where the maximum intensity of light is converted into electrical energy. Herein, we employ the quarter wavelength criteria using SiO₂, TiO₂ and ZnO to design the coating composed of single, double and triple layers. The thickness of individual layers was optimized for maximum light transmittance using essential Mcleod simulation software to produce destructive interference between reflected waves and constructive interference between transmitted waves.     

Laser scanning photothermal microscopy: fast detection and imaging of gold nanoparticles

We report on the design and construction of a laser scanning photothermal microscope and present images of gold nanoparticles of size as small as 5 nm. Laser scanning method allows fast image acquisition at 80 μs pixel dwell time so that a 500 × 500 pixel image is acquired in 20 s. Photothermal imaging at fast time scales can have potential applications in variety of fields including tracking of biomolecular transport processes.     

LIPID OXIDATION AND SENSORY CHARACTERISTICS OF FRESH AND CURED SAUSAGES FROM α-LINOLENIC ACID ENRICHED PORK

Forty-eight female piglets were raised with four levels of α-linolenic acid (0, 1.5, 2.5, 3.5%) to determine the effect of dietary fat on the fatty acid composition, sensory and storage stability of pork products. The degree of polyunsaturation in neutral lipids and phospholipids were increased significantly by the dietary LNA. The thiobarbituric acid reactive substances (TBARS) vaues of freshly prepared breakfast sausages with vacuum packaging remained low, but those of the loosely packaged, i. e., nonvacuumized, sausages increased more than 3 times during the 48 h storage period. The TBARS values of breakfast sausages frozen-stored for 3 months showed extensive lipid oxidation. The dietary LNA treatments and packaging had significant effects on the susceptibility of breakfast sausages to lipid oxidation. However, the oxidative stability of cured products was not affected by the dietary treatments. The results indicated that the pork enriched with polyunsaturated fatty acids could be used in cured products or uncured meat products protected by ‘hot vacuum packaging’without any sensory or quality deterioration due to lipid oxidation.     

Issues in Bioleaching: To Inoculate or not to Inoculate

Abstract

Two active bioleaching microbial strains were isolated from a zinc mineral sample. These bacteria isolates were grown on media containing sulfur or iron and reintroduced, individually or in combination, to the original mineral sample in controlled shake-flask bioleaching experiments. Uninoculated controls were included but no attempt was made to sterilize the solid material. On the contrary, growth of the same indigenous microorganisms was encouraged in the control flasks. Zinc was leached from both inoculated and uninoculated mineral at the same rate. The only difference was that the lag times before onset of leaching were shorter if active bacteria were present from the very beginning. In all cases, zinc was leached preferentially over iron. This difference was even more pronounced on leaching by sulfur-grown bacteria which did not extract iron to the same degree as iron-grown bacteria. When total leaching times required for 100% zinc extraction were compared, no statistically significant difference was observed between the inoculated and uninoculated tests. This conclusion may have some bearing on experimental and process design, when decisions must be made on whether to stimulate leaching by addition of extraneous bacteria or by fostering the proliferation of indigenous microorganisms.     

Feeding Dietary Oils with Tocopherols: Effects on Internal Qualities of Eggs During Storage

The effects of feeding menhaden, flax, palm, or sunflower oils with to-copherols to laying hens on the internal quality of eggs during 40-days storage were examined. Dietary tocopherols increased (P < 0.05) the tocopherol content of eggs. Addition of tocopherols increased (P < 0.05) the Haugh unit at 40-days storage in menhaden, flax, and palm oil eggs. Dietary tocopherols increased (P < 0.05) the content of 20:5 n-3 and 22:6 n-3 in menhaden oil eggs. At 40-days storage, the TBA values in menhaden oil eggs were reduced (P < 0.05) by dietary tocopherols. Storage decreased (P < 0.05) 8-tocopherol in the flax and sunflower oil eggs. Yolk pH increased during storage (P < 0.05).     

DIETARY OILS AND TOCOPHEROL SUPPLEMENTATION ON CHOLESTEROL OXIDE FORMATION IN FREEZE-DRIED CHICKEN MEAT DURING STORAGE

The influence of dietary oils [fish (FO), flax (LO), palm (PO) and sunflower (SO) oil] and tocohperol supplementation on the oxidation of cholesterol and lipids of chicken meat was investigated. Lipid oxidation in chicken meat powders was determined by thiobarbituric acid reactive substances (TBARS) and cholesterol oxidation products were estimated by capillary gas chromatography (GC) after trimethylsilylation. Peak identities from GC were confirmed by mass spectrometry. Freeze-dried chicken meat powder, stored in contact with air at room temperature for four months showed the presence of 7α- and 7β-hydroxycholesterol, 7-ketocholesterol, α and β-epoxide, and cholestane-triol. Total cholesterol oxides contents significantly (P < 0.05) increased with storage. The amount of cholesterol oxides in the meat powder was the highest in FO and SO group, and lowest in PO group. Lipid and cholesterol oxidation were accelerated by the presence of long-chain PUFA. Lipid and cholesterol stability of chicken meat were improved by the dietary supplementation of tocopherol.