On some generalized ageing orderings

Some partial orderings which compare probability distributions with the expo- nential distribution, are found to be very useful to understand the phenomenon of ageing. Here, we introduce some new generalized partial orderings which de- scribe the same kind of characterization of some generalized ageing classes. We give some equivalent conditions for each of the orderings. Inter-relations among the generalized orderings have also been discussed

The bacterium, Staphylococcus aureus induced chromosome aberrations with their protection by penicillin, and mitotic inhibition in Syrian hamsters

The frequency of bone marrow chromosome aberrations in Syrian hamster, Mesocricetus auratus induced by the injection of log culture, saline suspension and culture filtrate of S. aureus was significantly high while the treatment of heat-killed bacterial suspension showed no difference with control data. In the first three treated series aberrations were of individual and gross types while others had only individual types. The chromatid breaks were nonrandom, the centro-meric region being less vulnerable and the distal region was more susceptible. The aberration frequency was significantly reduced when log culture, saline suspension and culture filtrate treated specimens were also injected with penicillin 1 hr before simultaneously and 1 hr after, of which the post-treatment rendered the maximum protection. Lastly, the treatment of isolated bacterial sample retarded the mitotic frequency significantly as compared to that of normal and controls

Growth mechanism of Langmuir-Blodgett films

Langmuir-Blodgett (LB) deposition is an astonishingly simple technique to grow well-ordered correlated metal-organic multilayers. To understand this growth mechanism, we have performed X-ray scattering and atomic force microscopic (AFM) studies on cadmium arachidate LB films exhibiting self-affine and logarithmic in-plane correlation at the interfaces. Using linear stochastic theory for interface evolution, it is proposed that a 1D deposition followed by a 2D desorption process is the growth mechanism of LB films. X-ray and AFM measurements confirm the crossover between these two growth regimes

Water Stress Assessment in Jharkhand State Using Soil Data and GIS

In this paper an attempt has been made to study the interrelationship of water resources available with that of soil class and its properties including soil drainage and erosional characteristics which has been used to generate drainage stress map and water stress map inferring the basic reason for water scarcity in the district of Jharkhand, India. It has been found that 62.71% of soil is classified as well – excessively drained soils whereas only 18.13% of soil is imperfectly- poorly drained. It was also found that only 12.31% and 28.4% of total soil show slight erosion and severe erosion characteristics whereas remaining is moderately eroded. Jharkhand state is facing acute water crisis and due to lowering of ground water table. Thus this work would help the administrators and decision makers in assessing the role of soil in groundwater recharge. It has been concluded that soil is an important factor that controls ground water recharge and water stress of the region. GIS has proved to be an important tool in assessing the area in short span of time. An attempt has been made to highlight that there are various natural parameters that control ground water recharge and soil is one of the controlling parameter in Jharkhand (INDIA)

Extraction of density profile for near perfect multilayers

A simple inversion scheme, based on Born approximation, to determine the electron density profile of near perfect multilayers from specular X-ray reflectivity data has been presented. This scheme is useful for semiconductor multilayers and other thin films, which are grown almost according to the designed parameters. We also indicate the possibility of separating out the contribution of interdiffusion and roughness in electron density profiles of interfaces by utilizing information obtained from the analysis of diffuse scattering data. The extracted compositional profile was used to calculate structural details of epitaxial films along the growth direction. Simulated and metal organic vapor phase epitaxy grown InP/InxGa1−xAs/InP quantum-well systems have been used to demonstrate this scheme

Nanopattern formation in self-assembled monolayers of thiol-capped Au nanocrystals

The structure and the stability of the transferred monolayers of gold-thiol nanoparticles, formed at air-water interface at different surface pressure, on to silicon surface have been studied using two complementary techniques, X-ray reflectivity and atomic force microscopy (AFM). Networklike nanopatterns, observed through AFM, of the in-plane aggregated nanoparticles can be attributed to the late stage drying of the liquid trapped in the islands formed by nanoparticles. During drying process the trapped liquid leaves pinholes in the islands which by the process of nucleation and growth carry the mobile nanoparticles on their advancing fronts such that the nanoparticles are trapped at the boundaries of similar adjacent holes. This process continues bringing about in-plane as well as out-of-plane restructuring in the monolayer until the liquid evaporates completely rendering a patterned structure to the islands and instability in the monolayer is then stabilized

Ripple structure of crystalline layers in ion-beam-induced Si wafers

Ion-beam-induced ripple formation in Si wafers was studied by two complementary surface sensitive techniques, namely atomic force microscopy (AFM) and depth-resolved X-ray grazing incidence diffraction (GID). The formation of ripple structure at high doses (~7×1017 ions/cm2), starting from initiation at low doses (~1×1017 ions/cm2) of ion beam, is evident from AFM, while that in the buried crystalline region below a partially crystalline top layer is evident from GID study. Such ripple structure of crystalline layers in a large area formed in the subsurface region of Si wafers is probed through a nondestructive technique. The GID technique reveals that these periodically modulated wavelike buried crystalline features become highly regular and strongly correlated as one increases the Ar ion-beam energy from 60 to 100 keV. The vertical density profile obtained from the analysis of a Vineyard profile shows that the density in the upper top part of ripples is decreased to about 15% of the crystalline density. The partially crystalline top layer at low dose transforms to a completely amorphous layer for high doses, and the top morphology was found to be conformal with the underlying crystalline ripple

Critical tissue concentration of zinc in short duration mungbean (Vigna radiata)

It could be concluded from the above study that growth pattern of short duration mungbean [Vigna radiata (L.) Wilczek] significantly influenced tissue Zn concentration at different stages. Plant tissue Zn concentration was moderate to highly correlated with dry matter production throughout the crop growth stages. Based on the quadratic relationship with dry matter production, the critical concentration of tissue Zn was higher (35.0 to 40.5 mg/kg) at early stage (30 DAS) which was reduced at 45 DAS (21.6 to 21.9 mg/kg). Considerable variation was also observed in critical Zn concentration with leaf position. Based on the variability of Zn concentration in plant tissues and relation with dry matter production, young fully expanded leaf at 45 DAS was found to be the efficient sampling plant part for the plant diagnostics of zinc. While, the optimum Zn dose for summer mungbean was quantified 14.5 mg/kg soil