788 research outputs found

    Superconductivity at 5K in NdO0.5F0.5BiS2

    Full text link
    We report appearance of superconductivity at 5K in NdO0.5F0.5BiS2 and supplement the discovery [1] of the same in layered sulfide based ZrCuSiAs type compounds. The bulk polycrystalline compound is synthesized by conventional solid state route via vacuum encapsulation technique. Detailed structural analysis showed that the studied compound is crystallized in tetragonal P4/nmm space group with lattice parameters a = 3.9911(3) {\AA}, c = 13.3830(2) {\AA}. Bulk superconductivity is established in NdO0.5F0.5BiS2 at 5K by both transport and magnetic measurements. Electrical transport measurements showed superconducting Tc onset at 5.2K and Tc ({\rho}=0) at 4.7K. Under applied magnetic field both Tc onset and Tc ({\rho} =0) decrease to lower temperatures and an upper critical field [Hc2(0)] of above 23kOe is estimated. Both AC and DC magnetic susceptibility measurements showed bulk superconductivity below 5K. Isothermal magnetization (MH) exhibited typical type II behavior with lower critical field (Hc1) of around 15Oe. Isothermal magnetization (MH) exhibited typical type-II behavior with lower critical field (Hc1) of around 15Oe. Specific heat [Cp(T)] is investigated in the temperature range of 1.9-50K in zero external magnetic field. A Schottky-type anomaly is observed at low temperature below 7K. This low temperature Schottky can be attributed to the change in the entropy of the system.Comment: 10 pages text + Figs (New Version):comments/suggestion welcome ([email protected]

    Synthesis and superconductivity of new BiS2 based superconductor PrO0.5F0.5BiS2

    Full text link
    We report synthesis and superconductivity at 3.7K in PrO0.5F0.5BiS2. The newly discovered material belongs to the layered sulfide based REO0.5F0.5BiS2 compounds having ZrCuSiAs type structure. The bulk polycrystalline compound is synthesized by vacuum encapsulation technique at 7800C in single step. Detailed structural analysis has shown that the as synthesized PrO0.5F0.5BiS2 is crystallized in tetragonal P4/nmm space group with lattice parameters a = 4.015(5) {\AA}, c = 13.362(4) {\AA}. Bulk superconductivity is observed in PrO0.5F0.5BiS2 below 4K from magnetic and transport measurements. Electrical transport measurements showed superconducting transition temperature (Tc) onset at 3.7K and Tc ({\rho}=0) at 3.1K. Hump at Tc related to superconducting transition is not observed in heat capacity measurement and rather a Schottky-type anomaly is observed at below ~6K. The compound is slightly semiconducting in normal state. Isothermal magnetization (MH) exhibited typical type II behavior with lower critical field (Hc1) of around 8Oe.Comment: Short note 10 pages text+figs. First report on PrO.5F.5BiS2 Su

    Deep vein thrombosis prevention with triad of soluble aspirin, pneumatic compression device and early mobilization in surgically managed proximal femur fracture: an observational study

    Get PDF
    Background: To evaluate the effectiveness of regime of thromboprophylaxis including soluble aspirin, pneumatic compression devices and early mobilization in prevention of deep vein thrombosis (DVT) with patients of proximal femoral fracture managed by internal fixation.Methods: The study was an observational study conducted at tertiary care hospital of Indian armed forces with sample size of n= 50, diagnosed case of fracture proximal femur and managed operatively with soluble aspirin and pneumatic compression devices and early mobilization. Patients were observed and evaluated periodically for 12 weeks post discharge with colour doppler assessment.Results: The findings at end of 2 Week, n=1 (2%, p<0.003) had findings suggested of DVT and n=49 (98%) had no signs of DVT. Next periodic evaluation at 6 weeks and 12 weeks n=50 (100% p<0.001) was devoid of any doppler findings suggestive of DVT.Conclusions: The observational prospective study demonstrated the triad of soluble aspirin, pneumatic compression and early mobilization were efficacious in prevention of DVT in surgically managed cases of fracture proximal femur

    Phase separation of a magnetic fluid: Equilibrium phases and non-equilibrium kinetics

    Full text link
    We study self-assembly in a colloidal suspension of magnetic particles by performing comprehensive molecular dynamics simulations of the Stockmayer (SM) model which comprises of spherical particles that are decorated by a magnetic moment. The SM potential incorporates dipole-dipole interactions along with the usual Lennard-Jones interaction, and exhibits a gas-liquid phase coexistence observed experimentally in magnetic fluids. When this system is quenched from the high-temperature homogeneous phase to the coexistence region, the non-equilibrium evolution to the condensed phase proceeds with the development of spatial as well as magnetic order. We observe density-dependent coarsening mechanisms - a diffusive growth law ℓ(t)∼t1/3\ell(t)\sim t^{1/3} in the nucleation regime, and hydrodynamics-driven inertial growth law ℓ(t)∼t2/3\ell(t)\sim t^{2/3} in the spinodal regimes. [ℓ(t)\ell(t) is the average size of the condensate at time tt after the quench.] While the spatial growth is governed by the expected conserved order parameter dynamics, the growth of magnetic order in the spinodal regime exhibits unexpected non-conserved dynamics. The equilibrium morphologies have density-dependent shapes which typically include the isotropic sphere and spherical bubble morphologies in the nucleation region, and the anisotropic cylinder, planar slab, cylindrical bubble morphologies in the spinodal region. The structures are robust and non-volatile and exhibit characteristic magnetic properties. For example, the oppositely magnetized hemispheres in the spherical morphology impart the characteristics of a {\it Janus particle} to it. The observed structures have versatile applications in catalysis, drug delivery systems, memory devices and magnetic photonic crystals to name a few.Comment: 12 pages, 8 figure

    FTP SERVLET

    Get PDF
    This paper presents new idea about the servlet we know about http servlet and generic servlet case of http servlet we use http protocol for the server side programming this is a protocol dependent servlet if we use ftp and SMTP protocol instead of http protocol then servlet will be protocol independent. An FTP servlet is an intermediate application that resides between the FTP server and the FTP client. It works as a proxy interposed within client/server communications and helps to unload some of the computing power of the FTP server and distribute it to the FTP servlet. It also provides a firewall and proxy friendly file transfer environment by wrapping FTP traffic over HTTP. FTP traffic can be wrapped over Https using a SSL certificate to provide enhanced security. Keywords: SMTP, wrapping FTP, enhanced securit

    Genetic analysis of grain yield and its contributing traits for their implications in improvement of bread wheat cultivars

    Get PDF
    Genetic analysis was carried out in 55 genotypes (10 parents and 45 F1s) through diallel mating design excluding reciprocals in bread wheat. Analysis of variance showed appreciable variability among the breeding material for almost all the traits under study. The highest value of phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) was found for flag leaf area (PCV=18.82, GCV=17.74), biological yield (PCV=12.98, GCV=11.70), grain yield (PCV=11.90, GCV=10.39) and harvest index (PCV=10.39, GCV=10.05). Highest heritability with highest genetic advance was estimated for flag leaf area (h2=52.24, GA=34.64), biological yield (h2=15.04, GA=21.71), harvest index (h2=18.19, GA=20.01), peduncle length (h2=31.72, GA=15.96) and spikelets per spike (h2=34.92, GA=12.96), therefore selection will be effective based on these traits. Grain yield was found significantly correlated (at <1% level of significance) with productive tillers (gr=0.3283**, pr=0.4347**), spike length (gr=0.1959**, pr=0.2203**), spikelets per spike (gr=0.4342**, pr=0.3813**), grains per spike (gr=0.7188**, pr=0.4918**), biological yield (gr=0.6101**, pr=0.6616**), harvest index (gr=0.3518**, pr=0.3227**) and thousand grain weight (gr=0.5232**, pr=0.3673**). Similarly path coefficient analysis estimates for biological yield (g=1.0524, p=1.0554), harvesting index (g=0.8862, p=0.8291), thousand grain weight (g=0.0588, p=0.0269), grains per spike (g=0.0496, p=0.0074), spike length (g=0.0209, p=0.0289), days to maturity (g=0.0142, p=0.0127), productive tillers (g=0.0186, p=0.0147), peduncle length (g=0.0123, p=0.0157), days to 50% flowering (g=0.0093, p=0.0072) and plant height (g=0.0042, p=0.0020) showed high positive direct effects on grain yield indicating that due importance should be given to these traits during selection for high yield

    Previous caesarean scar rupture: mortality averted a case report

    Get PDF
    Uterine rupture at the site of a previous cesarean section scar is an uncommon but catastrophic complication of pregnancy by associated with significant foetal and maternal mortality and morbidity. A 31-year old woman, G6P3A2L1 with previous lower segment cesarian section (LSCS), booked case was admitted at 37 week of gestation with complaint of leaking per vaginal (P/V) in our tertiary care centre. Patient had spontaneous labor pain, which subsided after few contractions and sustained hemorrhagic shock with utero placental insufficiency due to previous LSCS scar rupture. Due diligence and expeditious caesarean management strategy needs to be adopted in parturient with previous caesarean patients owing due to risk of scar rupture. Ultrasonography is a useful tool which can be used to assess women with previous cesarean section to carry out risk stratification for subsequent pregnancies

    Bulk Superconductivity in Bismuth-oxy-sulfide Bi4O4S3

    Full text link
    Very recent report [1] on observation of superconductivity in Bi4O4S3 could potentially reignite the search for superconductivity in a broad range of layered sulphides. We report here synthesis of Bi4O4S3 at 5000C by vacuum encapsulation technique and basic characterizations. Detailed structural, magnetization, and electrical transport results are reported. Bi4O4S3 is contaminated by small amounts of Bi2S3 and Bi impurities. The majority phase is tetragonal I4/mmm space group with lattice parameters a = 3.9697(2){\AA}, c = 41.3520(1){\AA}. Both AC and DC magnetization measurements confirmed that Bi4O4S3 is a bulk superconductor with superconducting transition temperature (Tc) of 4.4K. Isothermal magnetization (MH) measurements indicated closed loops with clear signatures of flux pinning and irreversible behavior. The lower critical field (Hc1) at 2K, of the new superconductor is found to be ~39 Oe. The magneto-transport R(T, H) measurements showed a resistive broadening and decrease in Tc (R=0) to lower temperatures with increasing magnetic field. The extrapolated upper critical field Hc2(0) is ~ 310kOe with a corresponding Ginzburg-Landau coherence length of ~100{\AA} . In the normal state the {\rho} ~ T2 is not indicated. Our magnetization and electrical transport measurements substantiate the appearance of bulk superconductivity in as synthesized Bi4O4S3. On the other hand same temperature heat treated Bi is not superconducting, thus excluding possibility of impurity driven superconductivity in the newly discovered Bi4O4S3 superconductor.Comment: 12 pages Text + Fig

    Kaons and antikaons in strong magnetic fields

    Full text link
    The in-medium masses of the kaons and antikaons in strongly magnetized asymmetric nuclear matter are studied using a chiral SU(3) model. The medium modifications of the masses of these open strange pseudoscalar mesons arise due to their interactions with the nucleons and scalar mesons within the model. The proton, the charged nucleon, has effects from the Landau energy levels in the presence of the magnetic field. The anomalous magnetic moments (AMM) of the nucleons are taken into consideration in the present study and these are seen to be large at high magnetic fields and high densities. The isospin effects are appreciable at high densities. The density effects are observed to be the dominant medium effects, as compared to the effects from magnetic field and isospin asymmetry. ~Comment: 22 pages, 4 figures, version to be published in Eur. Phys. Jour. A. arXiv admin note: text overlap with arXiv:1712.0799
    • …
    corecore