2,800 research outputs found
Neutral kaon photoproduction on the deuteron
Neutral kaon photoproduction on the deuteron has been investigated by
including the final state effects and compared with the experimental data.
Comparison shows that the models used in this calculation can reproduce the
data in the channel regions fairly well but still give over
predictions in the channel. It seems that the tensor target
asymmetries are more suitable for studying the final state effects. The
extractions of the elementary photoproduction amplitude are also demonstrated.Comment: 6 pages, 6 figures, talk given by A. Salam at Fourth Asia-Pacific
Conference on Few-Body Problems in Physics 2008 (APFB08), Depok, Indonesia,
August 19-23, 200
Role of the meson in photoproduction off the deuteron
Neutral kaon photoproduction off the nucleon and deuteron has been
reinvestigated by utilizing the new experimental data on both targets. An
isobar model for elementary operator and impulse approximation for the reaction
on the deuteron have been used. The available free parameters in the elementary
model have been extracted from both elementary and deuteron data. In contrast
to the elementary reaction, fitting the deuteron data requires an inclusion of
weighting factor. The result indicates that the angular distribution of the
elementary process does not show backward peaking behavior.Comment: 4 pages, 4 figures, prepared for the Fifth Asia-Pacific Conference on
Few-Body Problems in Physics 2011 (APFB2011), Seoul, Korea, August 22-26,
201
The coupling constants for an electroweak model with a unification symmetry
We introduce the sequence of spontaneous symmetry breaking of a coupling
between Pati-Salam and electroweak symmetries
in order to establish a mathematically consistent relation among the coupling
constants at grand unification energy scale. With the values of baryon minus
lepton quantum numbers of known quarks and leptons, by including right-handed
neutrinos, we can find the mixing angle relations at different energy levels up
to the electromagnetic scale.Comment: 8 page
Tropical Soil Labile Fractions of Copper in the Experimental Plots ±Ten Years After Application of Copper-Containing-Waste
Copper is reported to be retained in soils for a quite long time particularly in soil treated with some amendments. This research was intended to evaluate the soil labile fractions of Cu ±10 years after application of Cu-containing industrial waste, lime, and cassava-leaf compost. Soil samples were taken from topsoils and subsoils of ±10 years old experimental plots set up in 1998 and factorially treated with a metal-spoon industrial waste at 0, 15, and 60 Mg ha-1, lime at 0 and 5 Mg ha-1, and cassava-leaf compost at 0 and 5 Mg ha-1. The measured Cu labile fractions were compared to those in soils sampled at ±1.5 years and ±3 years after treatments. The results showed that the soil Cu labile fractions in waste treated soils were higher than those in the control treatments eventhough their concentrations decreased with the years of sampling. Lime showed a decreasing effect on soil labile Cu fractions, but the effect decreased with the years of sampling. The effect of cassava-leaf compost application on soil Cu labile fraction was in general not evidenced ±10 years after treatment
Multidimensional Gravity on the Principal Bundles
The multidimensional gravity on the total space of principal bundle is
considered. In this theory the gauge fields arise as nondiagonal components of
multidimensional metric. The spherically symmetric and cosmology solutions for
gravity on SU(2) principal bundle are obtained. The static spherically
symmetric solution is wormhole-like solution located between two null surfaces,
in contrast to 4D Einstein-Yang-Mills theory where corresponding solution
(black hole) located outside of event horizon. Cosmology solution (at least
locally) has the bouncing off effect for spatial dimensions. In spirit of
Einstein these solutions are vacuum solutions without matter.Comment: REVTEX, 13pages, 2 EPS figure
EVALUATION OF BIOACTIVE COMPONENTS AND ANTIOXIDANT ACTIVITY OF VERNONIA ELAEAGNIFOLIA DC. (ASTERACEAE) IN GLYCOPHYTIC AND HALOPHYTIC CONDITIONS
Objective: The investigate some of the antioxidant activities and bioactive potentials of Vernonia elaeagnifolia grown hydroponically in glycophytic and halophytic conditions.
Methods: Plants were grown in Hoagland solution and subjected to (Sodium chloride (NaCl) treatments. Plants cultivated without salt stress served as the control. The phytochemical analysis was done with the help of Gas Chromatography-Mass Spectrometry (GC-MS) and antioxidants were analyzed following standard procedures using UV-Visible Spectrophotometer.
Results: Significant changes were observed in the presence of antioxidants like superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), total polyphenols, proline and ascorbic acid. GPX and proline proved to be the major components in imparting salinity stress tolerance. The control showed the presence of 23 bioactive components while the treatment contained 19 components.
Conclusion: The study thus provides information regarding the place of collection of the particular plant. Glycophytic conditions prove to be the best choice in terms of bioactive components and fatty acid contents. The investigations reveal that the plant contains several bioactive components and antioxidants, which prove it as a promising plant for developing potential drugs
Signals in the Soil: Underground Antennas
Antenna is a major design component of Internet of Underground Things (IOUT) communication system. The use of antenna, in IOUT, differs from traditional communication in that it is buried in the soil. Therefore, one of the main challenges, in IOUT applications, is to establish a reliable communication. To that end, there is a need of designing an underground-specific antenna. Three major factors that can impact the performance of a buried antenna are: (1) effect of high soil permittivity changes the wavelength of EM waves, (2) variations in soil moisture with time affecting the permittivity of the soil, and (3) difference in how EM waves propagate during aboveground (AG) and underground (UG) communications. For the third challenge above, it is to be noted that lateral waves are dominant component in EM during UG2UG communication and suffer lowest attenuation as compared to other, direct and reflected, components. Therefore, antennas used for over-the-air (OTA) communication will not be suitable for UG communication because of impedance mismatch. This chapter focuses on developing a theoretical model for understanding the impact of soil on antenna by conducting experiments in different soil types (silty clay loam, sandy, and silt loam soil) and indoor testbed. The purpose of the model is to predict UG antenna resonance for designing efficient communication system for IOUT. Based on the model a wideband planar antenna is designed considering soil dispersion and soil–air interface reflection effect which improves the communication range five times from the antennas designed only for the wavelength change in soil. Furthermore, it also focuses on developing an impedance model to study the effect of changing wavelength in underground communication. It is also discussed how soil–air interface and soil properties effect the return loss of dipole antenna
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