1,126 research outputs found
A report on the occurrence of Bangana dero (Hamilton, 1822) from Deepor beel (Ramsar site no. 1207), Brahmaputra valley, Assam
Deepor beel (Latitude: 26°05?26??N to 26°09?26?? N; Longitude: 90°36' E to 90°41?25?? E) located in Kamrup district, Assam is a large (water spread area of 589 ha) natural wetland and a Ramsar site of international importance (Site number 1207 declared in 2002) having enormous biological and environmental importance. The wetland receives water from surface run-off as well as from two hill streams (Basistha and Kalamoni) and drains into River Brahmaputra, through a small rivulet (Khanajan). The beel supports a number of endemic endangered and threatened animals and plants that are included under IUCN red-list. Past studies indicated the occurrence of 67 fin-fish species in the beel. In a recent survey conducted by us, the beel Bangana dero (Synonyms: Cyprinus dero/ Labeo dero), a cyprinid fish, was collected for the first time from the beel. We collected as many as 28 specimens of B. dero from the beel during October 2016. The total length of the reported specimens ranged from 8.77 - 10.14 cm and weight ranged from 6.74 - 10.61 g. The length-weight relationship of the species was worked out as W = 0.074*L2.103. B. dero reportedly inhabits upland rivers, torrential hill-streams; adults migrate to warm downstream regions during the winter season (December-February). Thus, the occurrence of this species in Deepor beel indicates its possible downstream migration from one or both the feeder rivers (Basistha and Kalamoni) or migration from Brahmaputra River through its connecting channel. 
Photon sensitivity of superheated drop at room temperature
It has been reported so far that superheated drop detector made of R-12 at
room temperature are sensitive to neutrons yet insensitive to photons. This
property makes its use as one of the most useful neutron dosimeter. The photon
sensitivity of R12 at room temperature when exposed to 59.54kev photons
obtained from radioactive Am has been noted for the first time in our
laboratory. This discovery is important nt only from the point of view of basic
science but more important to the users of R12 in neutron dosimetry to take
note of this in assessing the neutron dose correctly.Comment: 3pages, 1 fig. Nuclear Instruments and Method A, 2000, (accepted
INSDOCâS contribution to bibliometrics
Traces the history of bibliometric research, training and activities in INSDOC. Describes briefly the objectives, facilities, services, research activities, and publications of National Centre on Bibliometrics
Standardization of setting temperature and time for fish meat
Meat to water ratio used for washing was 1:3 for oil sardine and mackerel; but for pink perch and croaker, it was 1:2. Again the washing process was repeated three times for oil sardine and mackerel; but two times for pink perch and croaker. The washed meat was mixed with 2.5% NaC1 and set at +5°C and +40°C for 1, 2 and 3hrs. The gel strength and expressible water content was measured. Basing on this study, setting temperature at +40°C was selected and with respect to time 1hr for sardine and mackerel and 3hrs for pink perch and croaker was selected
Superheated drop as a neutron spectrometer
Superheated drops are known to vaporise when exposed to energetic nuclear
radiation since the discovery of bubble chamber. As the degree of superheat
increases in a given liquid, less and less energetic neutrons are required to
cause nucleation. This property of superheated liquids are being utilised to
develope the neutron spectromer. A new principle of neutron spectrometry using
Superheated liquid are developed and the developed principle has been tested by
Am-Be neutron source.Comment: 9 pages, 8 figures. accepted in Nucl.Instru.MethA,200
Evaluation of Anthelmentic and Antimicrobial Activity of the Extract of the Root of the Plant Jasminum multiflorum(Andr.)
As per qualitative evaluation in different solvents of the root of the plant satisfies the presence of cardiac glycosides along with trace quantities of steroid and saponins. Among them the petroleum ether extract of the root of the plant Jasminum multiflorum was evaluated for anthelmintic activity and the ethanolic extract was evaluated for antimicrobial activity.1,2 Traditionally this species are used in indolent ulcer, pitta and inflammation. Only few CNS activity are reported on ethanolic extract of aerial part of the plant, though the root of the plant is more potent as per folkore claim. The petroleum ether extract was investigated for anthelmentic activity using earthworm (Pheretima posthuma) at different concentration (5mg/ml â 50 mg/ml). As standard albendazole suspension (10mg/ml) and 3% solution of normal saline was used as control. The death and paralysis time were recorded and compared. Extract exhibit significant anthelmentic activity at (100mg/ml) concentration and found effective.1,3,4The ethanolic fraction of the root of the plant was collected and evaporated to dryness under vacuum to avoid the presence of even less quantity of ethanol in the extract. Two Gram (+ve) bacteria namely Bacillius subtilis, Staphylococcus aureus and two Gram (-ve) ve bacteria namely Escherichia coli and Klebsiella pneumonia were selected for the estimation of antimicrobial activity depending on zone of inhibition. It was seen that 100mg/ml concentration of the extract showed maximum activity against Klebsiella pneumonia with a zone of inhibition 0.5mm and for others it ranged from 0.3 to 0.4 mm. 1,4,5
Keywords: Jasminum multiforum; anthelmintic; antimicrobial; zone of inhibitio
Model of multifragmentation, Equation of State and phase transition
We consider a soluble model of multifragmentation which is similar in spirit
to many models which have been used to fit intermediate energy heavy ion
collision data. We draw a p-V diagram for the model and compare with a p-V
diagram obtained from a mean-field theory. We investigate the question of
chemical instability in the multifragmentation model. Phase transitions in the
model are discussed.Comment: Revtex, 9 pages including 6 figures: some change in the text and Fig.
Auger decay of degenerate and Bose-condensed excitons in CuO
We study the non-radiative Auger decay of excitons in CuO, in which two
excitons scatter to an excited electron and hole. The exciton decay rate for
the direct and the phonon-assisted processes is calculated from first
principles; incorporating the band structure of the material leads to a
relatively shorter lifetime of the triplet state ortho excitons. We compare our
results with the Auger decay rate extracted from data on highly degenerate
triplet excitons and Bose-condensed singlet excitons in CuO.Comment: 15 pages, revtex, figures available from G. Kavoulaki
Quantum saturation and condensation of excitons in CuO: a theoretical study
Recent experiments on high density excitons in CuO provide evidence for
degenerate quantum statistics and Bose-Einstein condensation of this nearly
ideal gas. We model the time dependence of this bosonic system including
exciton decay mechanisms, energy exchange with phonons, and interconversion
between ortho (triplet-state) and para (singlet-state) excitons, using
parameters for the excitonic decay, the coupling to acoustic and low-lying
optical phonons, Auger recombination, and ortho-para interconversion derived
from experiment. The single adjustable parameter in our model is the
optical-phonon cooling rate for Auger and laser-produced hot excitons. We show
that the orthoexcitons move along the phase boundary without crossing it (i.e.,
exhibit a ``quantum saturation''), as a consequence of the balance of entropy
changes due to cooling of excitons by phonons and heating by the non-radiative
Auger two-exciton recombination process. The Auger annihilation rate for
para-para collisions is much smaller than that for ortho-para and ortho-ortho
collisions, explaining why, under the given experimental conditions, the
paraexcitons condense while the orthoexcitons fail to do so.Comment: Revised to improve clarity and physical content 18 pages, revtex,
figures available from G. Kavoulakis, Physics Department, University of
Illinois, Urban
Processing of aluminum-graphite particulate metal matrix composites by advanced shear technology
Copyright @ 2009 ASM International. This paper was published in Journal of Materials Engineering and Performance 18(9) and is made available as an electronic reprint with the permission of ASM International. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplications of any material in this paper for a fee or for commercial purposes, or modification of the content of this paper are prohibited.To extend the possibilities of using aluminum/graphite composites as structural materials, a novel process is developed. The conventional methods often produce agglomerated structures exhibiting lower strength and ductility. To overcome the cohesive force of the agglomerates, a melt conditioned high-pressure die casting
(MC-HPDC) process innovatively adapts the well-established, high-shear dispersive mixing action of a twin screw mechanism. The distribution of particles and properties of composites are quantitatively evaluated.
The adopted rheo process significantly improved the distribution of the reinforcement in the matrix with a strong interfacial bond between the two. A good combination of improved ultimate tensile strength (UTS) and tensile elongation (e) is obtained compared with composites produced by conventional processes.EPSR
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