Developing and testing the ellipsoidal gravity model manipulator ELGRAM

The commonly used representation of potential as a truncated series of spherical harmonics leads to global models that consist of set of coefficients c nm , s nm (OSU91, EGM96), that can be successively used by a spherical harmonics manipulator to compute values of the potential and its functionals (geoid undulation, gravity anomaly, deflection of the vertical) at any point of given coordinates (φ, λ, h). The approximations involved both in the computations of the coefficients, from satellite and terrestrial measurements, and in their use in the synthesis of potential functionals make desirable the development of different computational techniques. In view of the actual requirements of more and more precise potential representation it is useful to develop a manipulator working with series of ellipsoidal harmonic functions. To this aim, appropriate equations relating geoid undulation, gravity anomaly, deflections of the vertical to anomalous potential T expanded in ellipsoidal series have been deduced, and a source code for their computation have been written and tested, comparing results with 'classical' spherical synthesis. In the paper the main steps of analytical computations are shown, the structure and use of the new software is illustrated and some results of the comparisons are reported

Oxidation of total organic content in lake water samples: a case study

The oxidn. of total org. content (TOC) present in the two selected Bangalore city lake (Medahalli and Ulsoor lakes) water samples at two different seasons of the year 2010 using photocatalyst TiO2 as been studied. The different forms of TiO2 such as anatase, rutile and mixed form (Degussa P25) are used for the study. The mixed form (mixt. of anatase and rutile) has given better results in photooxidn. than the individual TiO2 forms. The oxidn. of these pollutants present in the wastewater will be oxidized by photo​/ photocatalysis and the extent of contamination and oxidn. are measured by COD and BOD tests. The photooxidn. studies were made under natural sun light illumination. The efficiency and the rate consts. for the oxidn. of TOC are calcd. and presented. The TOC oxidn. reactions are found to follow first order kinetics. The rate consts. for photocatalytic oxidn. of TOC of the Medahalli lake samples of June and Dec. months are 0.333 and 0.49 (× 10-​4 s-​1) and for Ulsoor lake samples are 0.52 and 0.666 (× 10-​4 s-​1) resp

Description of nuclear octupole and quadrupole deformation close to the axial symmetry: Octupole vibrations in the X(5) nuclei 150Nd and 152Sm

The model, introduced in a previous paper, for the description of the octupole and quadrupole degrees of freedom in conditions close to the axial symmetry, is used to describe the negative-parity band based on the first octupole vibrational state in nuclei close to the critical point of the U(5) to SU(3) phase transition. The situation of 150Nd and 152Sm is discussed in detail. The positive parity levels of these nuclei, and also the in-band E2 transitions, are reasonably accounted for by the X(5) model. With simple assumptions on the nature of the octupole vibrations, it is possible to describe, with comparable accuracy, also the negative parity sector, without changing the description of the positive-parity part.Comment: 8 pages, 5 figure

Environmental Dependencies for Star Formation Triggered by Expanding Shell Collapse

Criteria for gravitational collapse of expanding shells in rotating, shearing galaxy disks were determined using three-dimensional numerical simulations in the thin shell approximation. The simulations were run over a grid of 7 independent variables, and the resultant probabilities for triggering and unstable masses were determined as functions of 8 dimensionless parameters. When the ratio of the midplane gas density to the midplane total density is small, an expanding shell reaches the disk scale height and vents to the halo before it collapses. When the Toomre instability parameter Q, or a similar shear parameter, Q_A, are large, Coriolis forces and shear stall or reverse the collapse before the shell accumulates enough mass to be unstable. With large values of C=c_sh/(GL)^0.2, for rms velocity dispersion c_sh in the swept-up matter and shell-driving luminosity L, the pressure in the accumulated gas is too large to allow collapse during the expansion time. Considering ~5000 models covering a wide range of parameter space, the common properties of shell collapse as a mechanism for triggered star formation are: (1) the time scale is 4*sqrt(C/2 pi G rho) for ambient midplane density rho, (2) the total fragment mass is ~2x10^7 Msun, of which only a small fraction is likely to be molecular, (3) the triggering radius is ~2 times the scale height, and the triggering probability is ~0.5 for large OB associations. Star formation triggered by shell collapse should be most common in gas-rich galaxies, such as young galaxies or those with late Hubble types.Comment: 7 pages, 6 figures, MNRAS in pres

PHYTOCHEMICAL SCREENING OF INFLORESCENCE OF PIPER BETLE

Objective: The objective of the current study is to determine the phytoconstituents present in the Inflorescence of Piper betle (IPB). Methods: Phytochemical screening was performed to analyse the phytoconstituents present in IPB and the same was identified by TLC. The phytoconstituents were also estimated quantitatively. Results: Phytochemical screening showed the presence of alkaloids, flavonoids, saponins, tannins and polyphenols. TLC results indicated and confirmed the presence of alkaloids, polyphenols, flavonoids and tannins. On quantification IPB was found to contain 4.2±1.661 mg/ml and 1.523±0.156 mg/ml of flavonoids and tannins respectively. Conclusion: The present study suggests that Inflorescence of Piper betle can be a good source of secondary metabolites

Description of nuclear octupole and quadrupole deformation close to the axial symmetry and phase transitions in the octupole mode

The dynamics of nuclear collective motion is investigated in the case of reflection-asymmetric shapes. The model is based on a new parameterization of the octupole and quadrupole degrees of freedom, valid for nuclei close to the axial symmetry. Amplitudes of oscillation in other degrees of freedom different from the axial ones are assumed to be small, but not frozen to zero. The case of nuclei which already possess a permanent quadrupole deformation is discussed in some more detail and a simple solution is obtained at the critical point of the phase transition between harmonic octupole oscillation and a permanent asymmetric shape. The results are compared with experimental data of the Thorium isotopic chain. The isotope Th-226 is found to be close to the critical point.Comment: 17 pages, 5 figures, 8 tables; 3 new references added, misprints correcte