Heavy metals are governed by parent material of soils and influenced by the soil physicochemical properties and soil and crop management practices. This paper evaluates total heavy metal concentrations in rainfed soils under diverse management practices of tropical India. Vertisols (clayey soils with high shrink/swell capacity) had the highest concentrations of heavy metals. However, chromium (Cr) content was above the threshold value in Aridisol [calcium carbonate (CaCO 3 )]-containing soils of the arid environments with subsurface horizon development. Concentration increased at lower depths ([30 cm). Basaltic soils showed higher concentrations of nickel (Ni), copper (Cu) and manganese (Mn). Cadmium (Cd), cobalt (Co), Cu and Mn concentrations were higher in soils cultivated to cotton, whereas Cr concentration was above the threshold level of 110 mg kg -1 in food crop cultivated soils. As the specific soil surface is closely related to clay content and clay type, soil's ability to retain heavy metals is more closely tied to the specific surface than to the soil cation exchange capacity.

SrBi 2 Nb 2 O 9 (SBN) is a bismuth layered perovskite compound, due to its relatively high Curie temperature, has potential application as high ceramic transducer. Also, it is an attractive ferroelectric material that is being considered in non-volatile random access memory cells. Present article describes preparation, dielectric, impedance and modulus characteristics. Temperature and frequency dependence of dielectric permittivity, impedance and electric modulus of barium strontium bismuth niobate (Ba 0.1 Sr 0.9 Bi 2 Nb 2 O 9 , BSBN) have been studied in the range of 35-590• C and 45 Hz-5 MHz, respectively. The structural analysis of compound revealed orthorhombic at room temperature. Complex impedance Cole-Cole plots are used to interpret the relaxation mechanism. These plots shows the relaxation behavior as non-Debye type. By using the Cole-Cole plots grain and grain boundary contributions towards conductivity have been estimated. From electrical modulus formalism polarization and conductivity relaxation behavior in BSBN have been discussed. DC and AC conductivity measurements have been performed on BSBN.

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Black gram (Vigna mungo L. Hepper), is an extensively studied food crop which is affected by many abiotic and biotic factors, especially diseases. The yield potential of Black gram is shallow due to lack of genetic variability and biotic stress susceptibility. Core biotic stress factors include mung bean yellow mosaic virus (MYMV), urdbean leaf crinkle virus (UCLV), wilt (Fusarium oxysporum) and powdery mildew (Erysiphe polygoni DC). Although many studies determine resistant varieties to a particular disease, however, it is often complimented by low yield and susceptibility to other diseases. Hence, this study focuses on investigating the genetic relationships among three varieties and nine accessions of black gram having disease resistance to previously described diseases and susceptibility using random amplified polymorphic deoxyribonucleic acid (RAPD) markers. A total of 33 RAPD primers were used for diversity analysis and yielded 206 fragments. Number of amplified fragments ranged from two (OPN-1) to 13 (OPF-1). The highest similarity coefficient was observed between IC-145202 and IC-164118 (0.921), while lowest similarity was between PU-31 and IC-145202 (0.572). The genetic diversity obtained in this study along with disease analysis suggests PU31as a useful variety for the development of markers linked to MYMV, UCLV, wilt and powdery mildew resistance by marker-assisted back cross breeding and facilitates the production of crosses with multiple disease resistance.

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Weather prediction is a real time challenging issue witnessed by the world in the last decade. The prediction is becoming more complex due to the ever changing weather conditions. Many models have been discussed for predicting the weather data assuming the related attributes as independent variables. For effective analysis of the weather, it is necessary to understand various influencing factors that cause the weather changes. It is therefore necessary to identify the relationship between these attributes for better understanding of the weather data. In this article, a weather prediction model based on the spatial and temporal dependencies among the climatic variables together with forecasting analysis.

In this study, the effects of the process parameters on their performance characteristics of lead-induced Ti-6Al-4V alloy were investigated. Taguchi’s [Formula: see text] orthogonal array (OA) has been used to conduct the experiments. Four process parameters were considered each at three levels. Peak current, pulse-on-time, servo voltage and pulse-off-time were selected as process parameters on performance characteristics, namely, material removal rate (MRR), surface roughness (SR) and dimensional deviation (DD). A multi-attribute decision-making (MADM) technique, namely, analytic hierarchy process (AHP) and technique for order of preference by similarity to ideal solution (TOPSIS), has been used to investigate the multiple response characteristics. The weights for performance characteristics are determined by AHP. Finally, analysis of variance method has been employed effectively to bring out the influence of the process parameters associated with each performance characteristic, namely, maximization of MRR and minimization of SR and DD.

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