Stock assessment of the bony fishes in Iranian coastal waters of the Caspian Sea (2005-2007)

Exploitation of bony fishes resources started on 12 October 2005 and finished on 9 April 2006 in 2005-2006. 142 beach seines caught about 14333.4 tons of bony fishes by 47101 hauling. The total catch was estimated 21844.7 tones (Includes illegal fishery). Kutum, mullets and common carp comprised more than 97 percent of total catch. Length classes 39-40, 31-32 and 40-41 cm predominated for kutum, golden grey mullet and common carp, respectively. Age groups 3 to 5 year comprised 84.2, 74.8 and 83.7 percent for Kutum, golden grey mullet and common carp, respectively and age group 4 year was dominant with 42.0, 35.9 and 43.0 percent, respectively. K value and L_∞ calculated 0.26 (/year) and 58.3 cm for Kutum and 0.15 (/year) and 61.5 cm for golden grey mullet, respectively. The total biomass and MSY estimated about 24733.7 and 8550.4 tones for kutum and about 16948.0 and 4999.0 tones for golden grey mullet, respectively. Exploitation rate (E) calculated 0.71 and 0.70 for Kutum and golden grey mullet, respectively. In 2006-2007, the exploitation of bony fishes resources started on 12 October 2006 and finished on 7 April 2007 in 2006-2007. 134 beach seines caught about 14120.0 tons of bony fishes by 48470 hauling. The total catch was estimated 23801.8 tones (Includes illegal fishery). Kutum, mullets and common carp comprised more than 98.5 percent of total catch. Length classes 39-40 and 38-39 cm predominated for kutum and common carp, respectively and length classes 27-28 and 29-30 cm predominated for golden grey mullet. Age groups 3 to 5 year comprised 80.2 and 71.8 percent for kutum and golden grey mullet, respectively and age groups 4 to 6 year comprised 71.8 percent for common carp. Age group 3, 4 and 5 year was dominant with 35.5, 32.1 and 27.1 percent for kutum, golden grey mullet and common carp respectively. K value and L∞ calculated 0.27 (/year) and 60.7 cm for Kutum, 0.2 (/year) and 58.4 cm for golden grey mullet and 0.19 (/year) and 66.7 cm for common carp, respectively. The total biomass and MSY estimated about 46654.9 and 14801.4 tones for Kutum, about 19549.0 and 5748.4 tones for golden grey mullet and about 10584.3 and 2186.0 tones for common carp, respectively. Exploitation rate (E) calculated 0.69, 0.53 and 0.52 for kutum, golden grey mullet and common carp, respectively

Calculation of phonon spectrum and thermal properties in suspended aOE (c) 100 \u3e In (X) Ga1-X As nanowires

The phonon spectra in zinc blende InAs, GaAs and their ternary alloy nanowires (NWs) are computed using an enhanced valence force field (EVFF) model. The physical and thermal properties of these nanowires such as sound velocity, elastic constants, specific heat (C (v) ), phonon density of states, phonon modes, and the ballistic thermal conductance are explored. The calculated transverse and longitudinal sound velocities in these NWs are similar to 25% and 20% smaller compared to the bulk velocities, respectively. The C (v) for NWs are about twice as large as the bulk values due to higher surface to volume ratio (SVR) and strong phonon confinement in the nanostructures. The temperature dependent C (v) for InAs and GaAs nanowires show a cross-over at 180A degrees K due to higher phonon density in InAs nanowires at lower temperatures. With the phonon spectra and Landauer\u27s model the ballistic thermal conductance is reported for these III-V NWs. The results in this work demonstrate the potential to engineer the thermal behavior of III-V NWs