Abdollahzadeh Jamalabadi M.Y.,Chabhar Maritime University |
Abdollahzadeh Jamalabadi M.Y.,Gyeongsang National University
Journal of Porous Media | Year: 2015
This study reports the results of the numerical investigation of steady-state thermal developing forced convection between parallel plate channels. The Darcy-Forchheimer-Brinkman model is used for momentum equation. Based on the local thermal equilibrium taking into account the viscous dissipation and the heat generation in solid and fluid phases, temperature profiles of the solid and fluid are obtained numerically in a saturated porous medium, with walls being at constant temperature and constant heat flux. The temperature and the Nusselt number profiles are shown in figures for different dimensionless fluid parameters such as Prantdl, Darcy, Forchheimer, and Brinkman number and the effects of thermal parameters such as the dimensionless heat exchange coefficient, thermal conductivity ratio, fluid heat number and solid heat numbers on the length, and the heat transfer of the thermal developing region are revealed by parameter study. Furthermore, four terms contributing to the viscous dissipation are investigated and the comparisons between the effects of combinations of these terms with temperature boundary conditions are highlighted. © 2015 by Begell House, Inc.
Sharifian S.,Hormozgan University |
Kamrani E.,Hormozgan University |
Safaie M.,Hormozgan University |
Sharifian S.,Chabhar Maritime University
Tissue and Cell | Year: 2015
In this study, the reproductive biology of female freshwater crab Sodhiana iranica, oogenesis and ovarian development were described. An H-shaped ovary consisting of a pair of long ovarian sacs connected by a narrow bridge tube was located in the cephalothorax on the dorsal side of the stomach. Females at different stages of ovarian development were anesthetized and their ovaries were removed, photographed, fixed, and processed for histological examination. Based on the light microscopic observations of cells' sizes, chromatin patterns, and amount of lipid vesicles, the female germ cells could be classified into seven different stages: (1) oogonia (Oog), (2) primary oocytes (pOc), (3) early previtellogenic oocyte (Oc1), (4) late previtellogenic oocyte(Oc2), (5) early vitellogenic oocyte (Oc3), (6) late vitellogenic oocyte (Oc4), and (7) mature oocyte (mOc). Oog are small oval-shaped cells with irregular-shaped nuclei. Oog undergo first meiotic division to become primary oocytes. The primary oocytes are small oval-shaped cells with large nuclei. The secondary oocytes derived from 2nd meiosis and comprise five steps. Four ovarian development stages were found for females based on the number and types of oocytes present in each stage: spent I (Spent), II (Proliferative) and III (Premature) and stage IV (Mature). The ovaries, macroscopically, varied in size and color during each developmental stage and, microscopically, the ovarian stages differed in proportion oogonia, and the secondary oocytes. During ovarian stage I, ovary contains primarily oogonia, primary oocytes and Oc1. In stage II, contains mainly Oc1, Oc2, and Oc3, while in stage III the predominant cells are Oc4. Mature oocytes appear synchronously in stage IV. © 2014 Elsevier Ltd.