Influence of Ni doping on the electronic structure of Ni_2MnGa

The modifications in the electronic structure of Ni_{2+x}Mn_{1-x}Ga by Ni doping have been studied using full potential linearized augmented plane wave method and ultra-violet photoemission spectroscopy. Ni 3d related electron states appear due to formation of Ni clusters. We show the possibility of changing the minority-spin DOS with Ni doping, while the majority-spin DOS remains almost unchanged. The total magnetic moment decreases with excess Ni. The total energy calculations corroborate the experimentally reported changes in the Curie temperature and the martensitic transition temperature with x.Comment: 4 pages, 4 figures, accepted in Phys. Rev.

Effect of growth and yield parameters on Indian-mustard genotypes under varying environmental conditions in western Haryana

An experiment was conducted in Rabi season of year 2014-15 at Research Farm, Department of Agril. Meteorology, CCSHAU Hisar, Haryana and field area was adjacent to agrometeorological observatory at 290 10' N latitude, 750 46' E longitude and altitude of 215.2 m with Split Plot Design as main plot treatments consisted of three date of sowing viz.26thOctober, 5thNovember, and 15th November and sub-plots consisted of three varieties (Kranti, RH 406 and RH 0749) with four replications. Various growth and yield parameters such as plant height, LAI, dry matter accumulation, partitioning and yield attributes were higher in 26thOctober sown crop as compared to 5th and 15th November at all the growth intervals. The crop sown on 26th October (1870.3 kg/ha) produced highest seed yield as compared to 5th (1525.5 kg/ha) and 15th November (1099.8 kg/ha). Among varieties, RH0749 recorded highest seed yield because LAI, biomass accumulates were performed better as compared to RH 406 and Kranti. There was significant interaction between growing environment and varieties with respect to growth and yield parameters. From the above study it was concluded that normal or early sowing of Indian mustard may be practisized for achieving higher seed yield and improved growth and yield attributes in western Haryana conditions

Experimental and theoretical electronic structure of EuRh2As2

The Fermi surfaces (FS's) and band dispersions of EuRh2As2 have been investigated using angle-resolved photoemission spectroscopy. The results in the high-temperature paramagnetic state are in good agreement with the full potential linearized augmented plane wave calculations, especially in the context of the shape of the two-dimensional FS's and band dispersion around the Gamma (0,0) and X (pi,pi) points. Interesting changes in band folding are predicted by the theoretical calculations below the magnetic transition temperature Tn=47K. However, by comparing the FS's measured at 60K and 40K, we did not observe any signature of this transition at the Fermi energy indicating a very weak coupling of the electrons to the ordered magnetic moments or strong fluctuations. Furthermore, the FS does not change across the temperature (~ 25K) where changes are observed in the Hall coefficient. Notably, the Fermi surface deviates drastically from the usual FS of the superconducting iron-based AFe2As2 parent compounds, including the absence of nesting between the Gamma and X FS pockets.Comment: 4 pages, 4 figure

Factoring Central Asia in the Russia-India Energy Trade

The article looks into the Russia-India energy trade potential and its strategic significance with a particular focus on the Central Asian energy trade. Russia has become a major player in the energy market and its handling of Syrian crisis has enhanced its position in the Middle East that has impact on oil market and production scenario. India has been a growing at a rate of above 5% and its energy needs have been substantial. India and Russia share a very special relationship due to long-standing cultural and political ties and this has been a facilitator to India’s energy security needs. The Central Asian Republics hold a special position for Russia and India in terms of strategic security across South and Central Asian region. The two countries not only deeply connect themselves with the region but also find it necessary to preserve the region from religious extremism and terrorism that is worsened by the narcotics and arms trade. The Central Asian republics are a house to some of the world’s largest natural gas reserves and they have been exporting it large volumes through pipelines. However, the approach has not materialised as South Asia due to the Afghanistan situation. Therefore, Russia remains an important route to access energy resources from Eurasia and Central Asia in particular. India also has high exposure to the maritime energy trade with Africa and Latin America countries that contribute to the counting opportunity cost for accessing Central Asian energy. The paper highlights the significance of energy trade between Russia, India and Central Asian countries that could contribute to geopolitical stability across the region

Unusual temperature dependence of band dispersion in Ba(Fe(1-x)Ru(x))2As2 and its consequences for antiferromagnetic ordering

We have performed detailed studies of the temperature evolution of the electronic structure in Ba(Fe(1-x)Ru(x))2As2 using Angle Resolved Photoemission Spectroscopy (ARPES). Surprisingly, we find that the binding energy of both hole and electron bands changes significantly with temperature in pure and Ru substituted samples. The hole and electron pockets are well nested at low temperature in unsubstituted (BaFe2As2) samples, which likely drives the spin density wave (SDW) and resulting antiferromagnetic order. Upon warming, this nesting is degraded as the hole pocket shrinks and the electron pocket expands. Our results demonstrate that the temperature dependent nesting may play an important role in driving the antiferromagnetic/paramagnetic phase transition.Comment: 5 pages, 6 figure

Buffer zone restoration and development in Knuckles conservation area, Sri Lanka An overview of Darwin Initiative Project

The Knuckles Conservation Area, which extends to an area about 17, 500 ha of central uplands of SriLanka, is famous for its highly diverse species of flora and fauna, endemism and many unique habitats.Over few decades, much of the forest in the area was cleared for the cultivation of coffee, tea andthen cardamom. The buffer zone, therefore, consists of a mosaic of anthropogenically derived vegetationtypes that vary in habitat quality, including degraded grasslands and natural forest fragments underplantedwith Cardamom. In this context, a project primarily focussed on research, training andknowledge dissemination, funded by Darwin Initiative of the government of UK is jointly launched inKnuckles region by University of Aberdeen, UK and University of Peradeniya, Sri Lanka along withother partner organisations for three years. It has already passed the first sixth months of itsimplementation. The project aims to enhance the sustainable conservation of biological diversity andecosystem services in the Knuckles by addressing the main threats to environmental protection throughthe development of options for buffer zone management that improve the livelihoods of localcommunities. This paper is, therefore, supported with ideas and information gathered from preliminaryproject workshop and field observation at Knuckles, assess the relevancy of this project in the contextand explore the conservation related issues in Knuckles. Beyond that, in addition to the experiencewith the project so far, this paper examines the approach adopted for the restoration and developmentof Knuckles and its surrounding buffer zone.

Ba{1-x}KxMn2As2: An Antiferromagnetic Local-Moment Metal

The compound BaMn2As2 with the tetragonal ThCr2Si2 structure is a local-moment antiferromagnetic insulator with a Neel temperature TN = 625 K and a large ordered moment mu = 3.9 mu_B/Mn. We demonstrate that this compound can be driven metallic by partial substitution of Ba by K, while retaining the same crystal and antiferromagnetic structures together with nearly the same high TN and large mu. Ba_{1-x}K_xMn2As2 is thus the first metallic ThCr2Si2-type MAs-based system containing local 3d transition metal M magnetic moments, with consequences for the ongoing debate about the local moment versus itinerant pictures of the FeAs-based superconductors and parent compounds. The Ba_{1-x}K_xMn2As2 class of compounds also forms a bridge between the layered iron pnictides and cuprates and may be useful to test theories of high Tc superconductivity.Comment: 5 two-column typeset pages, 5 figures, 20 references; v2: minor revisions, 4 new references, published versio