Variation in grainy texture of commercial ghee in relation to laboratory ghee and its blends†

Ghee, a major Indian dairy product, has unique pleasing flavour and granular texture. Ten samples of commercial ghee were analysed for grainy texture, fatty acid composition and melting and crystallisation behaviour. These were compared with laboratory ghee and its blends with high melting fraction (HMF) or low melting fraction (LMF). Grain size and quantity of commercial ghee ranged from 0.200 to 0.330 mm and 1 to 40%, respectively, when incubated at 29 °C for 24 h. Laboratory ghee samples showed a grain size and quantity of 0.241 mm and 42%, respectively. Commercial samples with poor granularity had a lower level of saturated fatty acids, while those with bigger grains had a higher level of palmitic acid (>35%). The ratio of unsaturated to saturated fatty acids showed significant variation in these samples. Differential scanning calorimetric analysis of the samples also showed variation in melting and crystallisation behaviour. In general, the characteristics of commercial ghee with poor granularity resembled those of laboratory ghee blended with LMF while commercial ghee with bigger grains compared well with the ghee blended with HMF.     

EFFECT OF LOAD MODELING ON STEADY STATE VOLTAGE STABILITY

ABSTRACT

This paper discusses the importance of load modeling in power systems for voltage stability studies. The steady-state voltage stability analysis is carried out using the available continuation power flow. Different types of load models - constant power; constant current; constant impedance; and composite load, which is a combination of the first three models, are considered. The composite load model is obtained using the LOADSYN software, where the load dependency on voltage is considered. The concept of load connectivity is defined and the confusion about the critical point with respect to PV curves is clarified. It is shown that for nonlinear loads, the critical point is not at the tip of the PV curve.     

Mixed mobile ion effect on a.c. conductivity of boroarsenate glasses

In this article we report the study of mixed mobile ion effect (MMIE) in boroarsenate glasses. DSC and a.c. electrical conductivity studies have been carried out for $\boldsymbol{x}$ MgO?C(25 $\boldsymbol{-}$ $\boldsymbol{x}$ )Li ₂ O?C50B ₂ O ₃ ?C25As ₂ O ₃ glasses. It is observed that strength of MMIE in a.c. conductivity is less pronounced with increase in temperature and frequency. The results were explained on the basis of structural model (SM) proposed by Swenson and his co-workers supporting molecular dynamic results.