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Showing 2 results for Rarefaction


Volume 9, Issue 2 (6-2023)
Abstract

Here, the species richness of Campopleginae, a diverse subfamily of the Darwin wasps was studied in an almost organic damask rose plain located at 2600 m a.s.l., the south of Iran. Sampling was done using four Malaise traps for six months from April–October 2019. The total sampling efforts were 18 trap months. The integrated approach was used to assess the sample completeness profile, to infer true diversities of entire assemblages via asymptotic diversity estimates, to standardize the sample coverage via rarefaction and extrapolation, and to infer diversity via an evenness profile. I also used Homogenous, Homogenous (MLE), Chao1, Chao1-bc, iChao1, ACE, ACE-1, 1st order jackknife, and 2nd order jackknife to estimate the species richness of the studied Campopleginae community. Malaise traps yielded 491 individuals belonging to 24 morphospecies. Diadegma majale (Gravenhorst, 1829) included 64.7% of the total individuals collected, representing the highly dominated species. The estimated sample completeness profile showed that our data covers 59% of the total species in this community and thus 41% of species are undetected. The values for Shannon and Simpson diversity indices are 4.53 and 2.29, respectively. The models and non-parametric estimators estimated the species richness of Campoplegines from 24 – 50 species. This study provides a wealth of baseline data for the subfamily Campopleginae in the south of Iran in terms of biological control and conservation.
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Volume 13, Issue 6 (9-2013)
Abstract

Abstract- Hydrodynamics and Heat transfer of a gaseous flow in microchannels is performed numerically. Velocity and temperature at the channel inlet is uniform and the rarefaction effect is imposed to the problem via velocity slip and temperature jump boundary conditions, according to the slip flow regime. The channel is sufficiently long to reach fully developed flow at the outlet. The numerical methodology is based on the control volume finite difference scheme and discrete equations are solved using SIMPLE algorithm. Effects of various parameters such as viscous dissipation, rarefaction, axial conduction and thermal creep on heat transfer have been considered. The results indicate that the Nusselt number in microchannels has a different value than in conventional channels. Local Nu number is found to experience a jump by the presence of viscous dissipation. The magnitude of the jump is independ of the Brinkman number values. Heat transfer is affected in two opposite directions by rarefaction increasing. Also, as Peclet number increases, there is a weak increase in fully developed Nu number values but there is significant effect of Kn number on it.

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