Moisture sorption characteristics of mango–soy-fortified yogurt powder

Moisture adsorption isotherms of plain yogurt, mango–soy-fortified yogurt (MSFY) and MSFY containing 0.4% gelatin stabilizer (MSFYG) powder were determined at 20, 30, 40 and 50°C. A gravimetric static method was used under 0.11–0.81 water activity ranges for the determination of sorption isotherms that were found to be typical type II sigmoid. Experimental data were fitted to five mathematical models viz. modified Henderson, modified Chung–Pfost, Oswin, Smith and Guggenheim–Anderson–de Boer (GAB). It was found that both Oswin and GAB models were acceptable in describing equilibrium moisture content–equilibrium relative humidity (EMC–ERH) relationships for yogurt powder samples over the entire range of temperatures.     

Studies on Processing of an Alnico Scrap

This paper presents the results of research and development work on processing of alnico scrap, a secondary resource of nickel and cobalt, generated during the manufacturing of alnico magnets. The scrap contains 8–10% nickel, 10–12% cobalt, 32–50% of iron, 8–10% aluminium, 2% copper and remaining silica. Various processes such as acid leaching, aqueous chlorine leaching, salt roasting and cupric chloride leaching were studied in detail. Of these cupric chloride leaching was found to be most effective with respect to recovery and purity. It has been possible to obtain pure nickel and cobalt salts by cupric chloride leaching of the scrap, solvent extraction and precipitation of the salts. The overall recovery by the above process was almost 99%.     

Electrolytic Extraction of Beryllium

Beryllium possesses certain unique mechanical and physical properties which make it a special engineering material and an important alloy addition. However, its low density, high reactivity and high melting point along with its occurrence in the form of a very stable beryl ore—containing only about five percent beryllium—make its extraction difficult. The electrowinning of beryllium from molten beryllium and sodium chloride salt-mix is a low temperature commercial process. Conversion of beryl ore into beryllia precedes the fused salt electrolysis and several purification techniques are followed to produce high purity beryllium metal. This paper reviews the existing major industrial processes for beryllium production. A modified beryllium chloride-beryllium fluoride fused salt electrolysis is suggested on similar principles but with added advantage of a semi-continuous high efficiency process. The electrode reactions for this salt system have been analysed on the basis of reaction rate theory and the influence of operating parameters, such as the temperature, electrode areas, current density, etc., on the cell potential has been identified. A possible basic cell design has also been proposed.     

Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

The utilization of poly (2-hydroxyethylmethacrylate) grafted agar (Ag-g-P(HEMA)) as a matrix for the controlled release of 5-aminosalicylic acid was investigated. Grafted copolymers of 2-hydroxyethylmethacrylate (HEMA) monomers on agar were synthesized by microwave assisted method. In vitro drug release studies were performed at pH values of 2 and 7 in order to investigate the possibility of pH triggered release for colon targeted drug delivery. Further, the percent grafting vs. t₅₀ (the time taken for release of 50% of the enclosed drug) value was studied and the results indicate that it may be possible to develop a programmable drug release matrix based on grafted polysaccharide. Ag-g-P(HEMA) appears to be a useful matrix for controlled release.     

Assessing growth and yield of wheat using remotely-sensed canopy temperature and spectral indices

Abstract

Prediction models were developed for wheat to assess crop growth in terms of leaf area index, dry matter production and grain yield from remotely-sensed temperature and spectral indices. The cumulative stress degree days (SDD) for the period of flowering to grain formation stage showed significantly higher correlation with dry matter (r= — 0940) and grain yield (r= —0-939) whereas that, for the period grain formation to harvest stage, showed significantly higher correlation lpar;r= —0-967) for crop water use. Significant and positive correlations between dry matter, leaf area and grain yield with infrared/red, normalised difference (ND), transformed vegetation index and greenness index were attained with the latter providing the highest degree of predictability. Spectral indices measured between flowering to milking stages gave the best prediction indicating the suitability of this period for crop growth assessment by this technique. Inter-stage sensitivity analysis by using multiple regression approach also revealed that greenness and transformed vegetation indices could provide better prediction of dry matter and grain yield. From the values of regression coefficients the jointing to beginning of milk formation period of the crop was found to be the most sensitive stage influencing the yield of crop.     

Studies on power spinning of tubes

The mechanism of plastic flow in Power spinning of tubes is analysed. The total displacements in the three coordinate directions are determined by the grid line method, and the actual strain distribution established as functions of the coordinate positions, ‘r’, ‘θ’ and ’z’, Forces, evaluated on the basis of the work of plastic deformation method, are correlated with those experimentally measured with a three component electric strain gauge type spinning tool dynamometer, designed and fabricated for the purpose.     

On the stability of non-linear feedback systems with control-dependent noise

A frequency-domain criterion that gurantees asymptotic stability with probability one of a non-linear feedback system with control-dependent noise is derived. The results show that the effect of control-dependent noise in such systems is less damaging than that of state-dependent noise.     

Corrosion of Refractory Alloys in Molten Lithium and Lithium Chloride

Several refractory materials have been considered over the years as containment material for lithium and lithium halides. Surface modified refractory metals are being extensively investigated for containment of reactive metals, radionuclides and their compounds. An overview of experimental observations and results of liquid lithium corrosion of selected engineering refractory materials are presented. The nature of the degradation and its mechanism has been explained. The influence of temperature, microstructure, stress, impurities and service time on the corrosion behavior for various refractory alloys have been discussed. Selection rules for materials of containment for liquid lithium and lithium compounds have been suggested. Recent experimental observations on the behavior of tantalum and niobium-based refractory metal alloys in a specific molten salt environment comprising LiCl/Li₂O/Li/Li₃N at 725°C have been included in an effort to select suitable materials for molten salt equipment. It has been observed that oxygen contamination is particularly harmful for the refractory metal alloys where as nitrogen is deleterious to iron-based alloys.     

Studies on Processing of an Alnico Scrap

Abstract

This paper presents the results of research and development work on processing of alnico scrap, a secondary resource of nickel and cobalt, generated during the manufacturing of alnico magnets. The scrap contains 8-10% nickel, 10-12% cobalt, 32-50% of iron, 8-10% aluminium, 2% copper and remaining silica. Various processes such as acid leaching, aqueous chlorine leaching, salt roasting and cupric chloride leaching were studied in detail. Of these cupric chloride leaching was found to be most effective with respect to recovery and purity. It has been possible to obtain pure nickel and cobalt salts by cupric chloride leaching of the scrap, solvent extraction and precipitation of the salts. The overall recovery by the above process was almost 99%.     

ANTI-OXIDANT EFFECT OF QUERCETIN ON TYPE 2 DIABETIC ERYTHROCYTES

There is much evidence that oxidative stress is involved in the etiology of several diabetic complications. Many in vitro and in vivo studies have demonstrated that several parameters of red blood cell function and integrity are negatively affected by increased oxidative stress. Quercetin (3,3', 4',5,7-pentahydroxyflavone) is one of the most abundant bioflavonoids commonly present in most edible fruits and vegetables. Quercetin has been reported to prevent oxidant damage and cell death by scavenging free radicals. The present study was undertaken to evaluate the antioxidant effect of quercetin on markers of oxidative stress in erythrocytes from type 2 diabetic patients. Quercetin (at micromolar concentration) shows significant antioxidant effect in protecting erythrocytes from tert- butylhydroperoxide induced oxidative changes. These results suggest that a diet rich in quercetin may provide protection to diabetic patients against some late complications.

PRACTICAL APPLICATIONS

In recent years, there has been heightened interest in the possible therapeutic role of plant polyphenols for large number of human diseases. Among other known biological effects, plant polyphenols are known to have strong antioxidant properties. Out of more than 4,000 different types of plant polyphenols, relatively few are known to be effectively absorbed in the human digestive system. Among this group is the flavonoid quercetin that is present in many fruits and vegetables. We present here experimental proof of the protecting effect of this bioflavonoid on erythrocytes subjected to increased oxidative stress. Since diabetic patients are known to have increased oxidative stress, our results add to the scientific knowledge that a higher intake of diet rich in quercetin may protect diabetic patients from some late complications arising due to oxidative stress.