4,710 research outputs found

    Nuclear deformation and neutrinoless double-β\beta decay of 94,96^{94,96}Zr, 98,100^{98,100}Mo, 104^{104}Ru, 110^{110}Pd, 128,130^{128,130}Te and 150^{150}Nd nuclei in mass mechanism

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    The (ββ)0ν(\beta ^{-}\beta ^{-})_{0\nu} decay of 94,96^{94,96}Zr, 98,100^{98,100}Mo, 104^{104}Ru, 110^{110}Pd, 128,130^{128,130}Te and 150^{150}Nd isotopes for the 0+0+0^{+}\to 0^{+} transition is studied in the Projected Hartree-Fock-Bogoliubov framework. In our earlier work, the reliability of HFB intrinsic wave functions participating in the ββ\beta ^{-}\beta ^{-} decay of the above mentioned nuclei has been established by obtaining an overall agreement between the theoretically calculated spectroscopic properties, namely yrast spectra, reduced B(E2B(E2:0+2+)0^{+}\to 2^{+}) transition probabilities, quadrupole moments Q(2+)Q(2^{+}), gyromagnetic factors g(2+)g(2^{+}) as well as half-lives T1/22νT_{1/2}^{2\nu} for the 0+0+0^{+}\to 0^{+} transition and the available experimental data. In the present work, we study the (ββ)0ν(\beta ^{-}\beta ^{-})_{0\nu} decay for the 0+0+0^{+}\to 0^{+} transition in the mass mechanism and extract limits on effective mass of light as well as heavy neutrinos from the observed half-lives T1/20ν(0+0+)T_{1/2}^{0\nu}(0^{+}\to 0^{+}) using nuclear transition matrix elements calculated with the same set of wave functions. Further, the effect of deformation on the nuclear transition matrix elements required to study the (ββ)0ν(\beta ^{-}\beta ^{-})_{0\nu} decay in the mass mechanism is investigated. It is noticed that the deformation effect on nuclear transition matrix elements is of approximately same magnitude in (ββ)2ν(\beta ^{-}\beta ^{-})_{2\nu} and (ββ)0ν(\beta ^{-}\beta ^{-})_{0\nu} decay.Comment: 15 pages, 1 figur

    Development of the mathematical model of catalytic cracking: identification of hydrocarbon of the vacuum distillate usin chromatomass- spectrometry

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    Information about composition of catalytic cracking raw materials and products is required fordevelopment of mathematical model of catalytic cracking. The results of laboratory investigation ondetermination of the composition of catalytic cracking vacuum distillate were performed in this work. Groupcomposition of the catalytic cracking raw materials was defined using liquid-adsorption chromatographicseparation on silica gel. Paraffin-naphthenic and aromatic fraction was indefined by chromato-massspectrometry

    The Environmental Effects of Uranium Exploration and Mining

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    Uranium exploration and mining is increasing as the Nation\u27s demand for energy grows. The environmental impacts associated with this exploration and mining are not severe and compare favorably with impacts from the production of other energy resources

    Magnetic-order induced effects in nanocrystalline NiO probed by Raman spectroscopy

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    The magnetic-order induced effects in nanocrystalline NiO are investigated through the phonons and magnons observed in the Raman spectra. The key observations are (i) an anisotropy of the first-order transverse and longitudinal optical phonons, with a splitting on the order of 5 meV and (ii) a marked size and excitation wavelength variation of the two-magnon peak, which varies linearly with a redshift of similar to 50 cm(-1) with a size reduction from 105 to 30 mm The magnon-related peaks, in contrast to the phonons, are suppressed for near-resonance laser excitations. The experimental results are interpreted in terms of the exchange interactions and strong electron-electron correlations. The magnetization measurements shows a crossover to ferromagnetism with large coercivities and magnetization with decreasing size, which is shown to be due to the thermoinduced contribution

    New limit for the half-life of double beta decay of 94^{94}Zr to the first excited state of 94^{94}Mo

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    Neutrinoless Double Beta Decay is a phenomenon of fundamental interest in particle physics. The decay rates of double beta decay transitions to the excited states can provide input for Nuclear Transition Matrix Element calculations for the relevant two neutrino double beta decay process. It can be useful as supplementary information for the calculation of Nuclear Transition Matrix Element for the neutrinoless double beta decay process. In the present work, double beta decay of 94^{94}Zr to the 21+2^{+}_{1} excited state of 94^{94}Mo at 871.1 keV is studied using a low background \sim 230 cm3^3 HPGe detector. No evidence of this decay was found with a 232 g.y exposure of natural Zirconium. The lower half-life limit obtained for the double beta decay of 94Zr\rm^{94}Zr to the 21+2^{+}_{1} excited state of 94Mo\rm^{94}Mo is T1/2(0ν+2ν)>3.4×1019T_{1/2} (0\nu + 2\nu)> 3.4 \times 10^{19} y at 90% C.L., an improvement by a factor of \sim 4 over the existing experimental limit at 90\% C.L. The sensitivity is estimated to be T1/2(0ν+2ν)>2.0×1019T_{1/2} (0\nu + 2\nu) > 2.0\times10^{19} y at 90% C.L. using the Feldman-Cousins method.Comment: 11 pages, 7 figures, Accepted in Eur. Phys. J.

    Inverted porphyrins and expanded porphyrins: an overview

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    Porphyrins and metallopophyrins have attracted the attention of chemists for the past 100 years or more owing to their widespread involvement in biology. More recently, synthetic porphyrins and porphyrin-like macrocycles have attracted the attention of researchers due to their diverse applications as sensitizers for photodynamic therapy, MRI contrasting agents, and complexing agents for larger metal ions and also for their anion binding abilities. The number of π-electrons in the porphyrin ring can be increased either by increasing the numberof conjugated double bonds between the pyrrole rings or by increasing the number of heterocyclic rings. Thus, 22π sapphyrins, 26π rubyrins, 30π heptaphyrins, 34π octaphyrins and higher cyclic polypyrrole analogues containing 40π, 48π, 64π, 80π and 96π systems have recently been reported in the literature. These macrocycles show rich structural diversity where normal and different kinds of inverted structures have been identified. In this review, an attempt has been made to collect the literature of the inverted porphyrins and expanded porphyrins reported until December 2001. Since themeso aryl expanded porphyrins have tendency to form both inverted and non-inverted structures more emphasis has been given to meso aryl expanded porphyrins

    Community youth teams facilitating participatory adolescent groups, youth leadership activities and livelihood promotion to improve school attendance, dietary diversity and mental health among adolescent girls in rural eastern India: protocol for a cluster-randomised controlled trial

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    BACKGROUND: Improving the health and development of adolescents aged 10-19 years is a global health priority. One in five adolescents globally live in India. The Rashtriya Kishor Swasthya Karyakram (RKSK), India's national adolescent health strategy, recommends supporting community-based peer educators to conduct group meetings with boys and girls. Groups aim to give adolescents a space to discuss the social and health issues affecting them and build their capacity to become active community members and leaders. There have been no evaluations of the community component of RKSK to date. In this protocol, we describe the evaluation of the Jharkhand Initiative for Adolescent Health (JIAH), a community intervention aligned with RKSK and designed to improve school attendance, dietary diversity and mental health among adolescent girls aged 10-19 years in rural Jharkhand, eastern India. METHODS: The JIAH intervention is delivered by a community youth team consisting of yuva saathis (friends of youth), youth leadership facilitators and livelihood promoters. Teams conduct (a) peer-led Participatory Learning and Action meetings with girls and boys, mobilising adolescents, parents, health workers, teachers and the wider community to make changes for adolescent health and development; (b) group-based youth leadership activities to build adolescents' confidence and resilience; and (c) livelihood promotion with adolescents and their families to provide training and practical skills. We are evaluating the JIAH intervention through a parallel-group, two-arm, superiority, cluster-randomised controlled trial. The unit of randomisation is a geographic cluster of ~1000 people. A total of 38 clusters covering an estimated population of 40,676 have been randomised to control or intervention arms. Nineteen intervention clusters have adolescent groups, youth leadership activities and livelihood promotion. Nineteen control clusters receive livelihood promotion only. Study participants are adolescent girls aged 10-19 years, married or unmarried, in or out of school, living in the study area. Intervention activities are open to all adolescent boys and girls, regardless of their participation in surveys. We will collect data through baseline and endline surveys. Primary trial outcomes are school attendance, dietary diversity and internalising and externalising mental health problems. Secondary outcomes include access to school-related entitlements, emotional or physical violence, self-efficacy and resilience. TRIAL REGISTRATION: ISRCTN17206016. Registered on 27 June 2018

    Parametrization of dark energy equation of state Revisited

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    A comparative study of various parametrizations of the dark energy equation of state is made. Astrophysical constraints from LSS, CMB and BBN are laid down to test the physical viability and cosmological compatibility of these parametrizations. A critical evaluation of the 4-index parametrizations reveals that Hannestad-M\"{o}rtsell as well as Lee parametrizations are simple and transparent in probing the evolution of the dark energy during the expansion history of the universe and they satisfy the LSS, CMB and BBN constraints on the dark energy density parameter for the best fit values.Comment: 11 page

    Discrimination, molecular characterisation and phylogenetic comparison of porcine Eimeria spp. in India

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    Infections with Eimeria spp. are common in pigs worldwide,occasionally affecting animals clinically after weaning or during the fattening period when diarrhoea and weight loss can be observed upon infection with the more pathogenic species. Molecular characterization of pathogens is valuable to accurately delimit species and development novel diagnostics, although sequences which define Eimeria species that infect pigs are scarce. Only three of the eight common species are currently represented in GenBank. In this study we describe the occurrence of Eimeria species in pigs sampled in Punjab, India;going on to use the samples to generate new species-specific 18 S rDNA sequences for all of the previously uncharacterised species. Using these data we report the first phylogenetic analyses to include the eight Eimeria species that commonly infect the domestic pig (Sus scrofa domesticus).Consideration of phylogenetic trees produced using Maximum Likelihood, Neighbour Joining, Maximum Parsimony and Unweighted Pair Group Method with Arithmetic Mean methods indicate that the 18 S rDNA sequences present lower levels of genetic diversity than Eimeria which infect avian species and are insufficient to infer stable phylogenies
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