Superconductivity in Ru substituted BaFe2-xRuxAs2

The occurrence of bulk superconductivity at ~22 K is reported in polycrystalline samples of BaFe2-xRuxAs2 for nominal Ru content in the range of x=0.75 to 1.125. A systematic suppression of the spin density wave transition temperature (TSDW) precedes the appearance of superconductivity in the system. A phase diagram is proposed based on the measured TSDW and superconducting transition temperature (TC) variations as a function of Ru composition. Band structure calculations, indicate introduction of electron carriers in the system upon Ru substitutiom. The calculated magnetic moment on Fe shows a minimum at x=1.0, suggesting that the suppression of the magnetic moment is associated with the emergence of superconductivity. Results of low temperature and high field Mossbauer measurements are presented. These indicate weakening of magnetic interaction with Ru substitutionComment: 20 pages 10 figure

New approach towards imaging λ-DNA using scanning tunneling microscopy/spectroscopy (STM/STS)

A new methodology to anchor λ-DNA to silanized n-Si(111) surface using Langmuir Blodget trough was developed. The n-Si (111) was silanized by treating it with low molecular weight octyltrichlorosilane in toluene. Scanning tunneling microscopy (STM) image of λ-DNA on octyltrichlorosilane deposited Si substrate shows areas exhibiting arrayed structures of 700 nm length and 40 nm spacing. Scanning tunneling spectroscopy (STS) at different stages depict a broad distribution of defect states in the bandgap region of n-Si(111) which presumably facilitates tunneling through otherwise insulating DNA layer

A low frequency radio telescope at Mauritius for a Southern sky survey

A new, meter-wave radio telescope has been built in the North-East of Mauritius, an island in the Indian ocean, at a latitude of -20.14 deg. The Mauritius Radio Telescope (MRT) is a Fourier Synthesis T-shaped array, consisting of a 2048 m long East-West arm and a 880 m long South arm. In the East-West arm 1024 fixed helices are arranged in 32 groups and in the South arm 16 trolleys, with four helices on each, which move on a rail are used. A 512 channel digital complex correlation receiver is used to measure the visibility function. At least 60 days of observing are required for obtaining the visibilities up to 880 m spacing. The Fourier transform of the calibrated visibilities produces a map of the area of the sky under observation with a synthesized beam width 4'X 4.6'sec(dec+20.14) at 151.5 MHz. The primary objective of the telescope is to produce a sky survey in the declination range -70 deg to -10 deg with a point source sensitivity of about 200 mJy (3-sigma level). This will be the southern sky equivalent of the Cambridge 6C survey. In this paper we describe the telescope, discuss the array design and the calibration techniques used, and present a map made using the telescope

The laboratory millimeter and submillimeter spectrum of HCO

The rotational absorption frequencies of 68 new lines from the HCO radical in its ground electronic state have been measured in the millimeter and submillimeter spectral region. The large zero-field data set acquired has allowed the complex spectrum of this light asymmetric rotor with unpaired electronic spin and magnetic hyperfine interactions to be completely analyzed to within experimental accuracy (<0.1 MHz) for the first time. The wide range of states observed provides a highly accurate map of the rotational frequencies of the formyl radical, which should enable the abundance and excitation of interstellar HCO to be examined in detail

Path analysis for seed yield and its component characters in fenugreek (Trigonella foenum-graecum L.)

Fenugreek (Trigonella foenum-graecum L.) is an important spice crop of Rajasthan. A vastgermplasm collection is maintained at S.K.N. College of Agriculture, Jobner. Two hundredforty lines from this germplasm along with five promising varieties namely RMt-1, RMt-143,UM-144, UM-303 and local check were evaluated in an augmented block design at the researchfarm of S.K.N. College of Agriculture, Jobner on light textured soil. Results indicate that thegenotypes showed significant differences for all the characters under study. All the characterhad more than 80% broad sense heritability but only seed yield per plant, biological yieldand pods per plant had above 50% genetic advance expressed as % of mean. The associationanalysis revealed that the seed yield per plant was significant and positively associated withplant height, primary branches per plant, pods per plant, pod length, seeds per pod andbiological yield at both phenotypic and genotypic levels and with test weight at phenotypiclevel. Further path coefficient analysis revealed that characters such as biological yield, podsper plant and primary branches per plant were the important characters for the selection ofhigh yielding genotypes as they exerted positive direct effect as well as showed positivecorrelation with seed yield at both genotypic and phenotypic levels. &nbsp