Articles written in Pramana – Journal of Physics
Volume 1 Issue 4 October 1973 pp 177-187 Solids
ESR investigations on exchange coupled pairs of Cu ions in single crystals of Cu(dtc)2, isomorphously diluted with the corresponding diamagnetic zinc salt, are reported. The spin Hamiltonian parameters for the coupled species (
Volume 6 Issue 2 February 1976 pp 87-93 Solids
The isotherms for the alkaline earth fluorides (CaF2, SrF2 and BaF2) have been computed using the expression for the total free energy of a crystal in the quasiharmonic approximation. The theoretical points for SrF2 and BaF2 have been compared with the points derived from Bridgman’s experimental relation.
The temperature variation of the isothermal bulk modulus of the alkaline earth fluorides has been worked out on the basis of Axe’s shell model. The theoretica points are compared with the points obtained from the temperature variation of the elastic constants data. It is found that the vibrational contribution to the temperature variation of the elastic constants in these crystals is significant.
Volume 6 Issue 4 April 1976 pp 189-195 X-ray Crystallography
The crystal structure of a new form of L-isoleucine hydrochloride monohydrate C6H13O2NHClH2O (termed form II) has been determined using three-dimensional photographic data. This differs conformationally from the hydrochloride derivative (termed form I, Trommel and Bijvoet 1954) reported earlier. The crystal belongs to the orthorhombic space group P212121 with cell dimensions,
Volume 6 Issue 4 April 1976 pp 196-202 X-ray Crystallography
Using the Bijvoet difference data reported in the literature for four compounds,
Volume 6 Issue 4 April 1976 pp 203-208 Solids
The determination of the internal strains on the coupling parameter approach becomes very involved particularly when the number of atoms per unit cell is very large. It is shown in this paper that a knowledge of the site symmetry of the atoms helps one in determining the number of non-vanishing internal strain coefficients easily. The internal strain coefficients of two symmetry connected atoms can also be related. Examples are shown to illustrate these ideas.
Volume 9 Issue 3 September 1977 pp 283-296 Solids
A study of the hyperfine interaction in the ESR of Cu-Cu pairs in single crystals of copper diethyldithiocarbamate as a function of temperature has shown distinct differences in the hyperfine structure in the two fine structure transitions at 20 K, the spectrum not having the same hyperfine intensity pattern in the low field fine structure transition in contrast to that of the high field transition. The details of the structure of both the fine structure transitions in the 20 K spectrum have now been explained by recognizing the fact that the mixing of the nuclear spin states caused by the anisotropic hyperfine interaction affects the electron spin states | + 1 > and | −> differently. This has incidentally led to a determination of the sign of
Volume 13 Issue 3 September 1979 pp 281-292 Crystallography
The crystal packing of five planar molecules is considered in this paper. Each unit cell contains two non-equivalent molecules whose planes are inclined to each other. It is shown that the angle of inclination between the planes is completely determined by a simple geometrical criterion. A simple sequential arrangement of the four molecules defining the elementary parallelopiped of which the entire crystal is built leads to various configurations from which the one which has the least interaction energy can be picked out. Using a crude Lennard-Jones potential for the non-bonded interaction and a hard sphere model for the atoms, one can compute the crystal structure from the minimum energy criterion and this is found to be in fair agreement with the observed structure. This simple sequential packing with some modifications can provide an useful model for calculating the radial distribution function in amorphous solids involving planar groups.
Volume 19 Issue 3 September 1982 pp 203-213 Solid State Physics
The temperature variation of the Debye-Waller factors of Ba++ and F− ions in BaF2 powder has been studied using x-ray powder diffraction over the temperature range 77°–298°K. A continuous flow cryostat has been specially fabricated for this purpose for the YPC 50 NM powder diffractometer available in the department. The Debye-Waller factors of Ba++ and F− between room temperature and 879°K have been measured using single crystal neutron diffraction by Cooper
Volume 22 Issue 3-4 March 1984 pp 345-364 Nuclear Physics
The origin of the crystal field and its variation with temperature in several
Volume 23 Issue 3 September 1984 pp 423-432 Solid State Physics
Normal state electrical resistivity of the Chevrel phase compounds of the type Cu1.8Mo6S8−
Volume 29 Issue 2 August 1987 pp 1- Rapid Communication
The absolute thermopower of single phase YBa2Cu3O7 and Y0.8Er0.2Ba2Cu3O7 has been measured in the range 250 K to the superconducting transition temperature. It is found that these compounds show a large enhancement of thermopower in the range 150 K down to
Volume 30 Issue 5 May 1988 pp 419-421 Condensed Matter Physics
The specific heat of superconducting oxide compound, YBa2Cu3O7 −
Volume 39 Issue 2 August 1992 pp 109-116
Thermal conductivity of YBa2Cu3O7 has been measured on samples of a few mm thickness. Above
Volume 41 Issue 1 July 1993 pp 61-66
Melt grown samples of Y1.2Ba1.8Cu2.4O
Volume 43 Issue 3 September 1994 pp 211-217
The real (
Volume 92 Issue 2 February 2019 Article ID 0015 Research Article
CHANDAN DANANI DEEPAK AGGARWAL H L SWAMI VINAY MENON RITESH SRIVATSAVA AASHOO SHARMA DEEPTI SHARMA M HIMA BINDU JYOTI AGRAWAL M MANOAH STEPHEN NAVEEN RASTOGI PRAMIT DUTTA SOMESWAR DUTTA UPENDRA PRASAD M WARRIER R SRINIVASAN
Steady State Tokamak-2 (SST-2) will be an intermediate fusion machine before Indian DEMOnstration power reactor (DEMO) development to realise the reactor technologies. It is designed for fusion gain Q = 5 andfusion power in the range of 100–300 MW. Nuclear design analyses of SST-2 machine have been carried out to support the conceptual design work. Analyses have been carried out for two breeding blanket concepts: Indian lead–lithium ceramic breeder (LLCB) and helium-cooled ceramic breeder (HCCB). The analyses assess the tritium production and radiation shielding capability of the machine referring to the engineering design parameters. In this study, one-dimensional radiation transport calculations have been performed to assess the SST-2 nuclear responses for 1 full power year (FPY) operation. Nuclear responses such as tritium breeding ratio (TBR), various radiation loads to toroidal field (TF) coil have been calculated to obtain the radial build-up of SST-2 capable of breeding tritium and satisfying the shielding requirements. The assessment has been made using the ANISEN code andFENDL 2.1 cross-section library. It is observed that the TBRs with LLCB and HCCB blankets are 0.85 and 0.94, respectively. Shielding calculations confirm that the radial build is sufficient to protect the superconducting TF coils for 1 FPY.
Volume 93 | Issue 6
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