21,811 research outputs found
Parton Distributions in Impact Parameter Space
Fourier transform of the generalized parton distributions (GPDs) at zero
skewness with respect to the transverse momentum transfer gives the
distribution of partons in the impact parameter space. We investigate the GPDs
as well as the impact parameter dependent parton distributions (ipdpdfs) by
expressing them in terms of overlaps of light front wave functions (LFWFs) and
present a comparative study using three different model LFWFs.Comment: 13 pages, 6 figure
Some Barriers to Clean Technologies
Traditionally metallurgical industries have been using unclean technologies and the need for clean technologies cannot be over emphasised. There has always been a gap between technologies of production and those handling the environment problems arising out of production methods. The gap needs to be narrowed, and if possible eliminated by changing production technologies themselves.
There are barriers to clean technologies because of a wide-ranging; technical, financial, administrative, psycho-logical etc. This article deals with some of the non-technical factors and attempts to identify approaches that may be more fruitful
The effect of long-range forces on cold-atomic interaction: Ps-H system
The s-wave elastic phase-shifts and s-wave elastic cross sections are studied
to find the effect of long-range forces on cold-atomic interactions using a
modified static-exchange model for Ps-H system. A Feshbach resonance in the
triplet channel using the modified static-exchange model at the energy ~
3x10^{-6} eV caused by long-range forces in the Ps-H system is being reported.Comment: 7 pages, 2 figures, 1 tabl
On the anomalous afterglow seen in a chameleon afterglow search
We present data from our investigation of the anomalous orange-colored
afterglow that was seen in the GammeV Chameleon Afterglow Search (CHASE). These
data includes information about the broad band color of the observed glow, the
relationship between the glow and the temperature of the apparatus, and other
data taken prior to and during the science operations of CHASE. While differing
in several details, the generic properties of the afterglow from CHASE are
similar to luminescence seen in some vacuum compounds. Contamination from this,
or similar, luminescent signatures will likely impact the design of
implementation of future experiments involving single photon detectors and high
intensity light sources in a cryogenic environment.Comment: 6 pages, 5 figures, submitted to PR
Waste Management in Some Medium Sized Metallurgical Industries
In thispaper, an attempt has been made to discuss some aspects of the nature of wastes generated and their management in some medium sized metallurgical industries, viz. mini steel plants of (1) MIs Special Steels Limtited, Bombay; (2)MIs Sun Flag Iron and Steel Company Ltd., Bhandara Road; (3) MIs IPISTEEL,Dhenkanal; (4) MlsIncast Metal Private Limited, Bhubaneswar (Steel Casting); (5)
MIs Indo Flo gates Limited, Kalunga (Refractory Castings); (6) MIs Konark Malleables Private Limited, Jagatpur (Processing of Malleables) and (7) Mr's Foundry Forge Plant, Ranchi (Forging). The wastes considered are solid, liquid and gaseous entities. The solid wastes are in the form of slag, mill scale, used refractory, used moulding sand, coal ash, saw dust, metal turnings and borings,
various dusts from flue gases and dry grinding units, lime slurry and sludges. The liquid wastes are in the form of industrial effluents at ambient and higher temperatures.
The characteristics such as pfl, total suspended solids, total dissolved solids,dissolved oxygen, chemical oxygen and biological oxygen demands, oil and greases etc. are given quantitatively. The gaseous wastes consists of flue gases and fumes from furnaces and tar pots. These wastes may contain oxides of carbon, sulphur and nitrogen, cyanides, fluorides, etc. Values of these characteristics are given. Mention has been made of the requirements of the Central Pollution Control Board (CPCB)for the Iron and Steel Industry together with pollution control measures for better environmental management
Physical properties of Tolman-Bayin solutions: some cases of static charged fluid spheres in general relativity
In this article, Einstein-Maxwell space-time has been considered in
connection to some of the astrophysical solutions as previously obtained by
Tolman (1939) and Bayin (1978). The effect of inclusion of charge into these
solutions has been investigated thoroughly and also the nature of fluid
pressure and mass density throughout the sphere have been discussed.
Mass-radius and mass-charge relations have been derived for various cases of
the charged matter distribution. Two cases are obtained where perfect fluid
with positive pressures give rise to electromagnetic mass models such that
gravitational mass is of purely electromagnetic origin.Comment: 15 pages, 12 figure
Recrystallization of epitaxial GaN under indentation
We report recrystallization of epitaxial (epi-) GaN(0001) film under
indentation.Hardness value is measured close to 10 GPa, using a Berkovich
indenter. Pop-in burst in the loading line indicates nucleation of dislocations
setting in plastic motion of lattice atoms under stress field for the
recrystallization process. Micro-Raman studies are used to identify the
recrystallization process. Raman area mapping indicates the crystallized
region. Phonon mode corresponding to E2(high) close to 570 cm-1 in the as-grown
epi-GaN is redshifted to stress free value close to 567 cm-1 in the indented
region. Evolution of A1(TO) and E1(TO) phonon modes are also reported to
signify the recrystallization process.Comment: 10 pages, 3 figures
Einstein equations in the null quasi-spherical gauge III: numerical algorithms
We describe numerical techniques used in the construction of our 4th order
evolution for the full Einstein equations, and assess the accuracy of
representative solutions. The code is based on a null gauge with a
quasi-spherical radial coordinate, and simulates the interaction of a single
black hole with gravitational radiation. Techniques used include spherical
harmonic representations, convolution spline interpolation and filtering, and
an RK4 "method of lines" evolution. For sample initial data of "intermediate"
size (gravitational field with 19% of the black hole mass), the code is
accurate to 1 part in 10^5, until null time z=55 when the coordinate condition
breaks down.Comment: Latex, 38 pages, 29 figures (360Kb compressed
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