5,248 research outputs found
Phytochemical evaluation of Celastrus paniculatus seed oil extracted by a method used by ‘Uraanv’ tribe of Chhattisgarh
More than 35,000 plant species are being used in various human cultures around the world for medicinal purposes. Medicated oil plays an important role for prevention and cure of diseases in Ayurveda. Celastrus paniculatus seed oil is such wonderful medicinally useful oil. It is commonly known as Black-Oil tree, Intellect tree, Climbing-staff plant and Jyotishmati and “Tree of life” in Ayurveda. It possesses Anti-depressant, Anti-Parkinson, Anti-Alzheimer’s, Neuroprotective, IQ improving activity. In tribal district (Jashpur) of Chhattisgarh, Indian people uses traditional method to extract C. paniculatus oil. It is commonly used by the tribes for the treatment of various diseases like headache, muscular spasm and local inflammations. The present study aim is documentation of traditional method of oil extraction used by ‘Uraanv’ tribe. This paper also dealt with the Physicochemical and qualitative phytochemical evaluation of C. paniculatus seed oil. Oil yield by traditional method was 25%. Carbohydrate, reducing sugar, monosaccharide, protein, amino acid, steroid, flavonoid, alkaloid, fixed oil, phytosterols, saponin, diterpenoid and cardiac glycoside were found in the oil sample.The GC-MS analysis shows the presence of 47 compounds in the oil. These phytochemical might be responsible for the therapeutic effect of C. paniculatsus seed oil
Antiferromagnetic Order in Disorder-Induced Insulating Phase of SrRu_{1-x}Mn_xO_3 (0.4<x<0.6)
We have performed the powder neutron diffraction measurements on the solid
solutions of SrRu_{1-x}Mn_xO_3, and found that the itinerant ferromagnetic
order observed in pure SrRuO_3 changes into the C-type antiferromagnetic (AF)
order with nearly localized d electrons in the intermediate Mn concentration
between x=0.4 and 0.6. With increasing x, the AF moment is strongly enhanced
from 1.1 mB (x=0.4) to 2.6 mB (x=0.6), which is accompanied by the elongation
of the tetragonal c/a ratio. These results suggest that the substitution of Mn
for Ru suppresses the itinerant character of the d electrons, and induces the
superexchange interaction through the compression in the c plane. We have also
found that the magnetic and transport properties observed in our tetragonal
samples are quite similar to those of recently reported orthorhombic ones.Comment: 4 pages, 4 figure
FT-IR spectroscopic investigation of high sulphur assam coals and their solvent-extracts
The FT-IR spectroscopic techniques were used to
understand the structural feature of four samples of high
sulphur Assam coals and their extracts in polar solvents.
Pyridine, N, N-Dimethyl Acetamide and Ethyl Acetate
were used for extraction of the coals at their reflux
temperatures in a Soxhlet apparatus. The
difference-FT-IR spectroscopic technique was used to
characterize the compositions of extracts. The extracts
were found to contain characteristic absorption bands of
original coals. Both aromatic and aliphatic C-H stretching
bands were observed in the spectra of extracts. The
spectral interpretations of the extracts closely resembled
the parent coal structures. The relative transmittances of
characteristic bands in extract spectrum suggest that the
distribution of functional groups in coals were somewhat
effected due to the interaction with the solvents. The
spectra show some depletion of bands along with
increase in some regions. The information regarding the
structure of coal and extracts obtained by this method
are qualitative in nature but very much useful in coal
utilizations. © Geol. Soc. India
Strangeness dynamics and transverse pressure in relativistic nucleus-nucleus collisions
We investigate hadron production as well as transverse hadron spectra from
proton-proton, proton-nucleus and nucleus-nucleus collisions from 2 GeV
to 21.3 TeV within two independent transport approaches (HSD and UrQMD)
that are based on quark, diquark, string and hadronic degrees of freedom. The
comparison to experimental data on transverse mass spectra from , and
C+C (or Si+Si) reactions shows the reliability of the transport models for
light systems. For central Au+Au (Pb+Pb) collisions at bombarding energies
above 5 AGeV, furthermore, the measured transverse mass
spectra have a larger inverse slope parameter than expected from the default
calculations. We investigate various scenarios to explore their potential
effects on the spectra. In particular the initial state Cronin effect
is found to play a substantial role at top SPS and RHIC energies. However, the
maximum in the ratio at 20 to 30 AGeV is missed by ~40% and
the approximately constant slope of the spectra at SPS energies is not
reproduced either. Our systematic analysis suggests that the additional
pressure - as expected from lattice QCD calculations at finite quark chemical
potential and temperature - should be generated by strong
interactions in the early pre-hadronic/partonic phase of central Au+Au (Pb+Pb)
collisions.Comment: 20 pages, 15 figures, Phys. Rev. C, in pres
The hadron-quark phase transition in dense matter and neutron stars
We study the hadron-quark phase transition in the interior of neutron stars
(NS's). We calculate the equation of state (EOS) of hadronic matter using the
Brueckner-Bethe-Goldstone formalism with realistic two-body and three-body
forces, as well as a relativistic mean field model. For quark matter we employ
the MIT bag model constraining the bag constant by using the indications coming
from the recent experimental results obtained at the CERN SPS on the formation
of a quark-gluon plasma. We find necessary to introduce a density dependent bag
parameter, and the corresponding consistent thermodynamical formalism. We
calculate the structure of NS interiors with the EOS comprising both phases,
and we find that the NS maximum masses fall in a relatively narrow interval,
. The precise value of the
maximum mass turns out to be only weakly correlated with the value of the
energy density at the assumed transition point in nearly symmetric nuclear
matter.Comment: 25 pages, Revtex4, 16 figures included as postscrip
Distribution of compact object mergers around galaxies
Compact object mergers are one of the currently favored models for the origin
of GRBs. The discovery of optical afterglows and identification of the nearest,
presumably host, galaxies allows the analysis of the distribution of burst
sites with respect to these galaxies. Using a model of stellar binary evolution
we synthesize a population of compact binary systems which merge within the
Hubble time. We include the kicks in the supernovae explosions and calculate
orbits of these binaries in galactic gravitational potentials. We present the
resulting distribution of merger sites and discuss the results in the framework
of the observed GRB afterglows.Comment: 8 pages, 5 figures, submitted to MNRA
C2D Spitzer-IRS spectra of disks around T Tauri stars: I. Silicate emission and grain growth
Infrared ~5--35 um spectra for 40 solar-mass T Tauri stars and 7
intermediate-mass Herbig Ae stars with circumstellar disks were obtained using
the Spitzer Space Telescope as part of the c2d IRS survey. This work
complements prior spectroscopic studies of silicate infrared emission from
disks, which were focused on intermediate-mass stars, with observations of
solar-mass stars limited primarily to the 10 um region. The observed 10 and 20
um silicate feature strengths/shapes are consistent with source-to-source
variations in grain size. A large fraction of the features are weak and flat,
consistent with um-sized grains indicating fast grain growth (from 0.1--1.0 um
in radius). In addition, approximately half of the T Tauri star spectra show
crystalline silicate features near 28 and 33 um indicating significant
processing when compared to interstellar grains. A few sources show large
10-to-20 um ratios and require even larger grains emitting at 20 um than at 10
um. This size difference may arise from the difference in the depth into the
disk probed by the two silicate emission bands in disks where dust settling has
occurred. The 10 um feature strength vs. shape trend is not correlated with age
or Halpha equivalent width, suggesting that some amount of turbulent mixing and
regeneration of small grains is occurring. The strength vs. shape trend is
related to spectral type, however, with M stars showing significantly flatter
10 um features (larger grain sizes) than A/B stars. The connection between
spectral type and grain size is interpreted in terms of the variation in the
silicate emission radius as a function of stellar luminosity, but could also be
indicative of other spectral-type dependent factors (e.g, X-rays, UV radiation,
stellar/disk winds, etc.).Comment: 17 pages, 13 figures, accepted for publication by ApJ, formatted with
emulateapj using revtex4 v4.
High-precision photometry by telescope defocussing - VI. WASP-24, WASP-25 and WASP-26
The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013/) under grant agreement nos. 229517 and 268421. This publication was supported by grants NPRP 09-476-1-078 and NPRP X-019-1-006 from Qatar National Research Fund (a member of Qatar Foundation). TCH acknowledges financial support from the Korea Research Council for Fundamental Science and Technology (KRCF) through the Young Research Scientist Fellowship Programme and is supported by the KASI (Korea Astronomy and Space Science Institute) grant 2012-1-410-02/2013-9-400-00. SG, XW and XF acknowledge the support from NSFC under the grant no. 10873031. The research is supported by the ASTERISK project (ASTERoseismic Investigations with SONG and Kepler) funded by the European Research Council (grant agreement no. 267864). DR, YD, AE, FF (ARC), OW (FNRS research fellow) and J Surdej acknowledge support from the Communauté française de Belgique – Actions de recherche concertées – Académie Wallonie-Europe.We present time series photometric observations of 13 transits in the planetary systems WASP-24, WASP-25 and WASP-26. All three systems have orbital obliquity measurements, WASP-24 and WASP-26 have been observed with Spitzer, and WASP-25 was previously comparatively neglected. Our light curves were obtained using the telescope-defocussing method and have scatters of 0.5–1.2 mmag relative to their best-fitting geometric models. We use these data to measure the physical properties and orbital ephemerides of the systems to high precision, finding that our improved measurements are in good agreement with previous studies. High-resolution Lucky Imaging observations of all three targets show no evidence for faint stars close enough to contaminate our photometry. We confirm the eclipsing nature of the star closest to WASP-24 and present the detection of a detached eclipsing binary within 4.25 arcmin of WASP-26.Publisher PDFPeer reviewe
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