MICROWAVE DRYING OF ALOE VERA (ALOE BARBADENSIS MILLER): MATHEMATICAL MODELING, KINETICS AND MASS TRANSFER ASPECTS

Aloe vera has extensive application in food and pharmaceutical industry in fact contains 97 percent of water. It’s perishable in nature and poor shelf life makes it essential to study the drying characteristics of aloe vera. The objective of this present study is to investigate the effect of different microwave (MW) respective power levels (180 , 360 ,540 , 720 and 900 Watts ) regarding the  moisture ratio (MR), drying rate (DR), effective moisture diffusivity (EMD), specific energy consumption (SEC) and drying efficiency (DE) of aloe vera. The drying process took 70 - 26 .5 minutes for attainment of equilibrium moisture content. A mathematical model done by Midilli et al.  is considered to be the best and most suitable for a drying conditions among the various thin layer models. The effective moisture diffusivity value at 180 Watts (W) of MW power was found as 4.5 × 10-8 m2/sec. while it was raised to 9.45 x10-7 m2/sec at 900 W in this study. Lowest energy consumption 1.4 MJ/Kg water and maximum drying efficiency occurred at higher microwave power level 900 Watts due to less drying duration (time)

DESIGN, FABRICATION AND EXPERIMENTAL INVESTIGATION OF LAB TYPE DRYER FOR AGRO PRODUCT

A new lab type dryer, which consists of an electric air heater and a drying chamber, was fabricated and used for drying the agricultural products. The present lab type dryer system was successfully tested using Radish, Bitter Gourd, and also compared with open sun drying. The different parameters were noted and also graphs were plotted between various parameters which shows that the efficiency of the lab type dryer. Compared to open sun drying the lab type dryer prevented mass losses and provided better product quality

ACID GAS ABSORPTION STUDIES IN PACKED COLUMN

Carbon dioxide is a major greenhouse gas that results in climatic changes. Reducing CO2 emission for addressing the climatic change concerns is becoming increasingly important as the CO2 concentration in the atmosphere has increased rapidly since the industrial revolution. Many mitigation methods, including CO2 sequestration and novel CO2 utilization, are currently under investigation. Most of these processes require CO2 in a concentrated form. However the CO2 from large sources such as fossil fueled power plants is mixed with nitrogen, water vapor, oxygen and other impurities. The current commercial operations for capturing CO2 from flue gas use a chemical absorption method with Monoethanol Amine (MEA) as the sorbent. The method is expensive and energy intensive. The cost of capturing a ton of CO2 including removing impurities and compressing CO2 to supercritical pressure using existing MEA technology would be very high, and the power output would be significantly reduced by the energy consumption in capturing and compressing CO2. In this work alternative solvent ammonia, is used which can overcome the disadvantages of current technology using amines such as MEA and DEA

Size and weight reduction in Holothuria scabra processed as beche-de-mer

Growing demand for beche-de-mer in the marine export market has naturally led to considerable debate among fishery biologists in our country on the problem of irrational exploitation of the natural stock. Along the Tamil Nadu coast Holothuria scabra is fished for beche-de-mer preparation. Studies on the size at first maturity indicated that the spawning size is 201-230 mm and this size group after processing attains a reduced size of 73-80 mm. Revival of the natural stock can take place and this would help in encountering specimens beyond the size of 75 mm in length. More studies are required on the biology of Holothurians to determine precisely the period of maturity and spawning in different species in a year and it is advisable to observe a 'closed season' each year to conserve the holothurian resources

Study on Durability Characteristics of Self - Compacting Concrete with Fly Ash

This paper investigates the study of workability and durability characteristics of Self-Compacting Concrete (SCC) with Viscosity Modifying Admixture (VMA), and containing Class F fly ash. The mix design for SCC was arrived as per the Guidelines of European Federation of National Associations Representing for Concrete (EFNARC). In this investigation, SCC was made by usual ingredients such as cement, fine aggregate, coarse aggregate, water and mineral admixture fly ash at various replacement levels (10%, 20%, 30%, 40% and 50%). The super plasticizer used was Glenium B233 and the viscosity modifying agent used was Glenium Stream 2. The experiments are carried out by adopting a water-powder ratio of 0.45. Workability of the fresh concrete is determined by using tests such as: slump flow, T50, V-funnel, L-Box and U-box tests. The durability of concrete is tested by acid resistance, sulphate attack and saturated water absorption at the age of 28, 56 and 90 days

Statistical Screening of Supplementary Nitrogen Source for Enhanced Production of L-Asparaginase by Aspergillus terreus 1782

In the present work, Latin Square Design (LSD) was applied to find the best supplementary nitrogen source for extracellular L-asparaginase production by Aspergillus terreus MTCC 1782 using corn flour as substrate in submerged fermentation. The independent effect of supplementary nitrogen source such as ammonium chloride, urea and sodium nitrate was studied on growth and production of L-asparaginase by A. terreus. Statistical significance of the nitrogen sources was studied by performing analysis of variance (ANOVA) and graphical ANOVA for LSD using Data plot software. It was found that there is no significant difference on growth due to the change in supplementary nitrogen source studied. Urea was identified as best supplementary nitrogen source with mean L-asparaginase production of 33.25 IU mL–1 and mean biomass production of 12.99 mg mL–1

On Weakly Symmetric and Weakly Conformally Symmetric Spaces Admitting Veblen Identities

In the present paper some properties involving curvature tensor,conformal curvature tensor, Ricci tensor and scalar curvature, on weakly symmetric, weakly conformally symmetric and pseudo symmetric spaces are obtained