Absence of ferromagnetism in Mn- and Co-doped ZnO

Following the theoretical predictions of ferromagnetism in Mn- and Co-doped ZnO, several workers reported ferromagnetism in thin films as well as in bulk samples of these materials. While some observe room-temperature ferromagnetism, others find magnetization at low temperatures. Some of the reports, however, cast considerable doubt on the magnetism of Mn- and Co-doped ZnO. In order to conclusively establish the properties of Mn- and Co-doped ZnO, samples with 6 percent and 2 percent dopant concentrations, have been prepared by the low-temperature decomposition of acetate solid solutions. The samples have been characterized by x-ray diffraction, EDAX and spectroscopic methods to ensure that the dopants are substitutional. All the Mn- and Co-doped ZnO samples (prepared at 400 deg C and 500 deg C) fail to show ferromagnetism. Instead, their magnetic properties are best described by a Curie-Weiss type behavior. It appears unlikely that these materials would be useful for spintronics, unless additional carriers are introduced by some means.Comment: 23 pages, 9 figures. submitted to J. Mater. Chem 200

Radiative capture of polarized neutrons by polarized protons

A model-independent irreducible tensor approach to p(n,gamma)d is presented and an explicit form for the spin-structure of the matrix for the reaction is obtained in terms of the Pauli spin-matrices for the neutron and the proton. Expressing the multipole amplitudes in terms of the triplet --> triplet and singlet --> triplet transitions, we point out how the initial singlet and triplet contributions to the differential cross section can be determined empirically.Comment: Revised version; typeset using RevTeX4; 6 pages, no figure

Groundwater markets and water use efficiency: The case of Karnataka

This study, based on primary data collected from 120 groundwater users in eastern dry zone of Karnataka compares the water use efficiency among different categories of water users, viz. well owners who do not sell water, well owners who sell water either for agricultural or non-agricultural use and water buyers (both agricultural and nonagricultural). Some of the important findings are- • The cropping pattern varies between categories, with both the sellers and buyers preferring low water intensive mulberry crop, while the self user's category grew more water intensive crops. • Farmers who sold water for non-agricultural purposes earned the highest return (because of higher end-use price) and also made the most efficient use of water. Thus, making a point that end-use pricing is a key in shaping marginal productivity of water. • Compared to the self-users, farmers selling water for either agricultural or non-agricultural purposes realized higher marginal productivity. Thus,groundwater markets acted as an effective tool in enhancing efficient use of a scarce resource.This study explores efficiency and equity in groundwater markets in the hard rock areas of Karnataka. It compares the water use efficiency of farmers using groundwater for irrigating their land and also selling it for agricultural purpose (WSA, n=30), farmers using water for irrigating their land and also selling for non-agriculture purpose (WSNA, n=15), farmers who do not either sell or buy water but use it on their farms (WO, n=30), farmers who are buying groundwater for agriculture purpose (WBA, n=30), and buyers of water for non-agriculture purpose (WBNA, n=15). The Nash equilibrium framework describing the bargaining power of buyers and sellers of groundwater is used. Sidlaghatta taluk in eastern dry agroclimatic zone (EDZ) of Karnataka is chosen because it supports intensive groundwater markets. The objective of the study is to find out water use efficiencies among different groups of water users with the hypothesis that WSNA obtain higher water use efficiency than WSA, WBA, and WO.Groundwater markets, efficiency, equity, Resource /Energy Economics and Policy,

Groundwater markets and water use efficiency: The case of Karnataka

Research highlight based on a paper titled “Groundwater markets promoting efficiency in water use in agriculture in Karnataka.”Water market, Groundwater extraction, Water use efficiency, Wells, Crop production, Irrigation water, Domestic water, Pricing, Models, Policy, India, Karnataka, Demand and Price Analysis, Environmental Economics and Policy, Food Security and Poverty, Productivity Analysis,

Effective usage of e-resources

There is large quantity of subscribed e-resources which contain quality rich information in most of the technical institute libraries. In spite of advantages in terms of access and search capabilities, they are underused. Systematic plan has to be in place for their promotion of use. While a good ICT infrastructure is a prerequisite, it alone will not do. Proactive strategies are required and these need to be adopted imaginatively. Access to e-resources need to be made easier for both on campus and off campus users. Training will increase the confidence level of the users. Traditional awareness methods include: Personal visits, orientations, brochures, posters and displays. Newer technologies from the Web 2.0 such as RSS alert service, Blogs, Wikis and Face book make the interaction with the library not only interesting but also add more value

Phase ambiguity of the threshold amplitude in pp -> pp\pi^0

Measurements of spin observables in pp -> {\vec p}{\vec p}\pi^0 are suggested to remove the phase ambiguity of the threshold amplitude. The suggested measurements complement the IUCF data on {\vec p}{\vec p} -> pp\pi^0 to completely determine all the twelve partial wave amplitudes, taken into consideration by Mayer et.al. [15] and Deepak, Haidenbauer and Hanhart [20].Comment: 4 pages, 1 table