282 research outputs found
Efficient and high-âyielding protocol for the synthesis of nitriles from aldehydes
An operationally simple and high-âyielding procedure was developed for the conversion of aryl aldehydes into the corresponding nitriles using p-âtoluenesulfonic acid as a mild catalyst under microwave irradn. The products were characterized by IR spectral anal. and by comparison of the melting and b.ps. with the reported values
ChemInform Abstract: Molecular IodineâCatalyzed, Mild, Effective, Ecofriendly, MicrowaveâAssisted, OneâPot Synthesis of 5âArylmethylideneâ2âphenyloxazolâ4âones (Azalactones) under SolventâFree Conditions
The advantages of this method, compared to conventional methods, are good substrate generality, inexpensive reagents, environmentally benign catalyst and experimental simplicity
Effect of supplemental Vitamin E on the performance, metabolic profiles, and immune responses of dairy calves.
Forty-six Holstein heifer calves were used from birth to 3 rno to study the effect of supplemental vitamin E at 1400 or 2800 mg dl-a.-tocopherol acetate given orally at weekly intervals or 1400 mg dl-a-tocopherol by intramuscular injection. Weekly starter consumption was 10 to 27 % more (P=.12) and weekly weight gains were 9 to 25% more (P=.13) in supplemented calves. Creatine phosphokinase activity was negatively correlated with serurn tocopherol concentrations, indicating a subclinical muscular dystrophy in unsupplemented calves. Lymphocyte stimulation indices were positively correlated with serum tocopherol concentration. Calves given high level of oral supplementation had higher IgM antibody concentration. It was concluded that supplemental vitamin E is beneficial for calves reared on conventional complete starters to increase disease resistance and to obtain optimum performance.; Dairy Day, 1984, Kansas State University, Manhattan, KS, 1984
Localization of multi-class on-road and aerial targets using mmwave FMCW radar
publishedVersio
Stability of the lattice formed in first-order phase transitions to matter containing strangeness in protoneutron stars
Well into the deleptonization phase of a core collapse supernova, a
first-order phase transition to matter with macroscopic strangeness content is
assumed to occur and lead to a structured lattice defined by negatively charged
strange droplets. The lattice is shown to crystallize for expected droplet
charges and separations at temperatures typically obtained during the
protoneutronstar evolution. The melting curve of the lattice for small
spherical droplets is presented. The one-component plasma model proves to be an
adequate description for the lattice in its solid phase with deformation modes
freezing out around the melting temperature. The mechanical stability against
shear stresses is such that velocities predicted for convective phenomena and
differential rotation during the Kelvin-Helmholtz cooling phase might prevent
the crystallization of the phase transition lattice. A solid lattice might be
fractured by transient convection, which could result in anisotropic neutrino
transport. The melting curve of the lattice is relevant for the mechanical
evolution of the protoneutronstar and therefore should be included in future
hydrodynamics simulations.Comment: accepted for publication in Physical Review
Surface Tension between Kaon Condensate and Normal Nuclear Matter Phase
We calculate for the first time the surface tension and curvature coefficient
of a first order phase transition between two possible phases of cold nuclear
matter, a normal nuclear matter phase in equilibrium with a kaon condensed
phase, at densities a few times the saturation density. We find the surface
tension is proportional to the difference in energy density between the two
phases squared. Furthermore, we show the consequences for the geometrical
structures of the mixed phase region in a neutron star.Comment: 7 pages, 5 figures (Latex
Comparison of feed based intensification with conventional feeding practice in dairy cattle in Tumkur (Karnataka) and Yavatmal (Maharashtra)
A laboratory demonstration of rail grinding and analysis of running roughness and wear
Rail grinding has been widely used for rail maintenance to keep the performance of the rail track at satisfactory levels. However, there is a lack of knowledge on the relationship between different grinding parameters and the effect on the rails and the post-grinding evolution of roughness and wear. Rail undergoes significant levels of stress during grinding to remove any defects that appear during its life-cycle which can cause significant microstructural change. By developing a method of demonstrating rail grinding it will allow further investigation of the process and potentially the exploration of different grinding patterns. Moreover, an analysis of the roughness of wheel and rail is an input parameter in most modern simulation tools that could be associated with the coefficient of friction. This paper reports a laboratory demonstration of rail grinding followed by a series of tests to determine the wear of the rail and if there is a relationship between friction coefficient and roughness. The rail specimens that were ground have undergone a phase transformation and showed White Etching Layer (WEL) on
the contact surface. This was found to initially act protectively for the rail disc reducing the wear rates, but then contributed to crack formation. No clear long-term correlation was identified between the coefficient of friction and roughness during the testing, however a relationship could be drawn when test periods were studied individually
SL(2,Z) symmetries, Supermembranes and Symplectic Torus Bundles
We give the explicit formulation of the 11D supermembrane as a symplectic
torus bundle with non trivial monodromy and non vanishing Euler class. This
construction allows a classification of all supermembranes showing explicitly
the discrete SL(2,Z) symmetries associated to dualities. It hints as the origin
in M-theory of the gauging of the effective theories associated to string
theories.Comment: 13 pages, Late
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