Microwave-assisted extraction (MAE) and microwave-assisted hydrolysis (MAAH) were developed for the sample preparation of guava leaves prior to GC determination of quercetin and its glycosides. Ethanol was selected as the solvent. The optimum MAE temperature, particle size, solvent volume and MAE time are 120 degrees C, 40 - 60 mesh, 20 mL and 5 min, respectively; the optimum MAAH temperature a...

We have calculated the heat current in the normal metal/insulator/ supercon-ductor contacts with arbitrary transparency of the insulator barrier. In the tunneling limit (small transparencies), the heat flow out of the normal metal reaches its maximum at temperature T ≃ 0.3∆. At higher values of transparency , the interplay between single-particle tunneling and Andreev reflection determines opti...

A computer model has been used to simulate the discharge kinetics and parametric behaviour of a selfheated copper vapour laser for a wide range of optimum and non-optimum conditions. The results indicate that the ground state copper density and the peak electron temperature are the two most important parameters that affect laser performance. The results also confirm the existence of a threshold...

The halophilic bacterial isolates SS1, SS2, SS3, SS5, and SS8 were characterized for production of industrially important enzymes like amylase, protease, lipase, and glutaminase. Halophilic bacterial isolates SS1 and SS3 exhibited salt dependent extracellular amylase and protease activities. Both the halophilic isolates SS1 and SS3 exhibited maximum amylase and protease activities in the presen...

The thermal reaction norms of 4 closely related intertidal Nacellid limpets, Antarctic (Nacella concinna), New Zealand (Cellana ornata), Australia (C. tramoserica) and Singapore (C. radiata), were compared across environments with different temperature magnitude, variability and predictability, to test their relative vulnerability to different scales of climate warming. Lethal limits were measu...

The present paper investigates cellulose degrading bacteria present in kitchen waste for highest cellulase activity and growth of bacteria at optimum temperature and pH. Sample was collected from domestic kitchen waste and bacterial strains were isolated using nutrient agar media. Enrichment technique was used for isolating CDB (cellulose degrading bacteria) strains. The objective of research w...

Objective: Peel of Amorphophallus is considered as waste. In this study we checked for the presence of cellulase enzyme in this waste and investigated its biochemical properties. Methods: Presence of cellulase activity was confirmed by Congo red plate diffusion assay The optimum temperature, pH, substrate concentration for both CMCase and FPase activity was also determined by DNS method. Effect...

A thermodynamic model of a thermoelectric generator-driven thermoelectric heat pump (TEG-TEH) combined device is established considering the Thomson effect and the temperature dependence of the thermoelectric properties based on non-equilibrium thermodynamics. Energy analysis and exergy analysis are performed. New expressions for heating load, maximum working temperature difference, coefficient...

in the present work, attempts have been made to find appropriate coating by testing different compounds. results showed that the optimum enamel is a compound with 1 wt.% cobalt oxide, 3 wt.% chromium oxide (in addition to hundred percent) with the firing temperature of 840 ˚c. constants of vft equation were determined by examination of melting behavior of the optimum enamel and measurement of t...

the aim of the paper presented here is to develop the ti - micralloyed steel in otrer to oprtmize the mechanical properties after direct quenching from hot forging temperature. for this purpose, seven melts containing various amounts of titanium were prepared and cast in metal and sand molds. from the ingots, cast in metal mould, tractor links were produced by hot forging. the produced links we...