Inherent properties of binary tetrahedral semiconductors

A new approach utilising the concept of ionic charge theory has been used to explain the inherent properties such as lattice thermal conductivity and bulk modulus of 3,5 and 2,6 semiconductors. The lattice thermal conductivity of these semiconductors exhibit a linear relationship when plotted on a log scale against the nearest neighbour distance but fall on two straight lines according to the product of the ionic charge of the compounds. On the basis of this result a simple relationship of lattice thermal conductivity with bulk modulus is proposed and used to estimate the bulk modulus of these semiconductors. A fairly good agreement has been found between the experimantal and calculated values of these parameters for zinc blende structured solids.Comment: 6 pages, 19 reference

Segmentation of touching characters in upper zone in printed Gurmukhi script

A new technique for segmenting touching characters in upper zone of printed Gurmukhi script has been presented in this paper. The technique is based on the structural properties of the Gurmukhi script characters. Concavity and convexity of the characters has been studied and using top profile projections, the touching characters in upper zone have been segmented. Recognition rate of 91 % has been achieved for segmenting the touching characters in upper zone

Fodder Productivity of Different Genotypes of \u3cem\u3eCenchrus ciliaris\u3c/em\u3e under Hot Arid Climate of Thar Desert

Indian arid zone occupies about 31.7 million ha of land, of which 62% lies in western Rajasthan. The climate of the area is typically arid, characterized by hot dry summers, sub-humid monsoon and cold dry winters. The soils are coarse loamy sand with low level of nutrients. These factors render cropping an undependable proposition, while animal husbandry remains the main stake of the local people. Lasiurus sindicus, Cenchrus ciliaris, C. setigerus, Panicum antidotale, P. turgidum and Cymbopogon spp., are the main perennial grasses grow in this area. These grasses had three folds advantages in the arid agricultural economy, i.e., the cheapest livestock feed, soil builders and aid in soil conservation. Due to frequent droughts and overgrazing the productivity of the natural grasslands in the region has declined to \u3c 300 kg/ha per year. The ever existing gap between demand and supply of the fodder can be bridged by improving the rangelands by adopting improved grassland management techniques including genetically improved genotypes for their productivity and quality. Buffel grass (C. ciliaris L.) is one of the dominant grasses of Dichanthium-Cenchrus-Lasiurus grass cover of India (Dabadghao and Shankarnarayan, 1973). It is well distributed in hotter and drier parts of India, Mediterranean region, tropical and southern Africa. It is adapted to a wide range of soils and climatic conditions and can be cultivated in areas receiving rainfall from 150 to 1250 mm annually. It grows well on sandy to sandy-loam soils in semiarid and arid regions, forming mats or tussocks (Mansoor et al., 2002). The forage of this grass is highly palatable and rich in protein (Sawal et al., 2009). It has 6 to 10% crude protein, 34% crude fibre, 13% ash, 1.5% ether extract and 44% nitrogen free extract of dry matter at flowering. In earlier efforts at CAZRI, Jodhpur, germplasm was collected from different areas of arid zone and some accessions were identified for their fodder productivity and quality. Five genotypes were selected to assess their response for fodder production over the years under hot dry conditions

G × E Interaction and Heterosis in Elite Tomato Hybrids for Growth, Earliness and Fruit Parameters in Diverse Agro-Climatic Zones of Punjab

Six promising tomato hybrids selected from a pool of 60 F1 hybrids were evaluated for seven traits, along with the check hybrid (TH-1) at two locations falling under different agro-climatic zones of Punjab, India. G × E interaction was significant for early yield, fruit weight and total fruit yield, whereas, it was non-significant for fruit number, locule number, pericarp thickness and vine length. Overall higher mean-early-yield, fruit number, fruit weight and total yield at Ludhiana, rather than at Bathinda, may be due to higher organic carbon, available phosphorus and available potash and low electrical conductivity of the experimental soil at Ludhiana. Pooled analysis showed that hybrid TH-21 had the maximum early-yield (3.73 tha-1), fruit weight (72.7 g) and locule number (2.65), whereas, TH-23 had the highest fruit number per vine (53.7) and total fruit yield (51.2 tha-1). The magnitude of pooled standard heterosis was maximum for vine length (140.7%), followed by early yield (114.8%), total yield (88.3%), fruit number (49.7%), fruit weight (27.6%), pericarp thickness (16.4%) and locule number (-21.6%). On the basis of stability and superiority for fruit weight, fruit number, early and total yield, TH-21 was found to be the most promising hybrid, followed by TH-23

Physiological and biochemical response to higher temperature stress in hot pepper (Capsicum annuum L.)

The present study was conducted to evaluate the physiological and biochemical changes in some thermotolerant and thermosensitive chilli (Capsicum annuum L.) genotypes. Fourteen chilli genotypes (SL 461, PP 404, DL 161, MS 341, VR 521, PB 405, PS 403, SD 463, FL 201, AC 102, S 343, SL 462 and SL 464 along with sensitive check [Royal Wonder of bell pepper] were evaluated for heat tolerance. The observations on morpho-physiological and biochemical parameters were recorded at 45, 65, 85 and 105 days after transplanting (DAT) (high temperature period). On the basis of our studies, genotypes S 343, AC 102 and FL 201 were found to be relatively thermotolerant. However, high temperature markedly decreased the photosynthetic activity of chilli plants by decreasing the photosynthetic pigments in leaf chloroplasts of all the genotypes. The levels of ascorbic acid, total soluble sugars and total phenols increased in the leaves of all the genotypes with the maturity of the crop. Electrolyte leakage and proline content also increased with rise in temperature. Genotypes AC 102 and S 343 were able to accumulate the maximum ascorbic acid, proline, total soluble sugars and total phenols under heat stress conditions. Decrease in fruit set percent led to reduction in the total yield per plant. Maximum yield was observed in genotype S 343 followed by FL 201

A Study of Low Energy Ar+ Ion Bombardment Induced Lattice Damage in (100) n-GaAs by Channeling

It has been found that sputter cleaning of GaAs single crystals results in damage or loss of crystallinity in the first few tens of nanometers of the crystal. The damage is a result of both - energetic Ar ions impinging on and being incorporated in the GaAs surface and the resultant preferential sputtering of As from the GaAs lattice. A study of this damage which was done at room temperature and at -110 °C was made by the use of Selected Area Electron Channeling Patterns. The relationship between the degree of surface disorder, as shown by the pattern degradation, and sputtering parameters (ion beam voltage and ion beam dose) was experimentally obtained. The energy regime investigated was 0.5 to 5 keV with sputtering times from 5 to 20 minutes. The results showed increasing contrast degradation in the selected area channeling patterns (SACPs) with increasing incident ion energies from 0.5 to 4 keV, a maxima in contrast degradation for a sputtering time of 10 minutes and greater contrast degradation at room temperature than at -110 °C