Natural convection in a trapezoidal enclosure with partial heating from below and symmetrical cooling from the sides has been investigated numerically. The heating is simulated by a centrally located heat source on the bottom wall, and four different values of the dimensionless heat source length, 1/5, 2/5, 3/5, 4/5 are considered. The laminar flow field is analyzed numerically by solving the steady, two-dimensional incompressible Navier-Stokes and energy equations. The Cartesian velocity components and pressure on a collocated (non-staggered) grid are used as dependent variables in the momentum equations discretized by finite volume method; body fitted coordinates are used to represent the trapezoidal enclosure, and grid generation technique based on elliptic partial differential equations is employed. SIMPLE algorithm is used to adjust the velocity field to satisfy the conservation of mass. The range of Rayleigh number is (103≤ Ra ≤105) and Prandtl number is 0.7. The results show that the average Nusselt number increases with the increases of the source length.
The shortage of irrigation water requires specific measures. One of these measures is the application of the rationing system (a period of irrigation followed by a period of drought). This system could have an effect on the behavior and properties of irrigation canals. So, studying rationing system on the irrigation canals is important both in civil engineering and water resources engineering, especially if these channels constructed with gypsum soil. This study includes the calculation of seepage velocity and water content in each cycle (10 days wetting and 10 days of drying). The model is built for this research contains four samples, two samples for untreated soil one of them expos
The problem of research is to identify the uses of Iraqi women for Facebook and the motives of these uses and the innovations that have been achieved from them, in view of the increasing role-played by social networking sites in the lives of individuals in general and women in particular.The research seeks to identify the following: Identify the extent to which Iraqi women use Facebook and the usage motives and innovations achieved by the interviewees When they using Facebook. This study belongs to the descriptive studies that are interested in monitoring the characteristics of a particular phenomenon to identify its characteristics and characteristics.This study adopted the survey methodology to test the hypotheses of the study and how
... Show MoreThis study aimed to conduct a comparative analysis of seven calliphorid species of third- instar larvae that were collected from central Iraq. The purpose was to morphologically characterize these species and develop an identification key to differentiate them from closely related species. Scanning Electron Microscope (SEM) graphical images and high-resolution traditional optical microscopes were used to analyze the morphological characteristics of the species Calliphora vomitoria (Linnaeus, 1758), C. vicina Robineau-Desvoidy, 1830, Chrysomya albiceps (Widemann, 1819), Ch. rufifacies (Macquart, 1844), Ch. megacephala (Fabricius, 1794), Lucilia cuprina (Wiedemann, 1830), and L. sericata (Meigen, 1826). An identification key was const
... Show MoreLipase enzyme has attracted a lot of attention in recent years because of its diverse biotechnological applications. The present study was conducted to screen germinated seeds of four crops, namely sunflower (Helianthus annuus), flaxor linseed (Linum usitatissimum ), peanut (Arachis hypogaea ) and castor bean (Ricinus communis), for the activity of their lipases. to the study also included the extraction and purification of lipase from the seeds of the most promising crop using different solvents. The results indicated that the maximum enzymatic activity (0.669 U/ml) was obtained when 0.1 M Tris-HCl buffer extract was used after 3 days of seed germination of all the tested species, as compared to the other test solvents
... Show More2-hydrazinylbenzo[d]thiazole compound [1] is produced from reaction of 2-mercapto-benzothiazole with hydrazine hydride in ethanol. Compound [1] reacted with maleic anhydride in DMF to produce (Z)-4-(2-(benzo[d] thiazol-2yl) hydrazinyl)-4-oxobut-2-enoic acid [compound (2)]. While the treatment of compound [2] with the ammonium persulfate (NH4)2S2O8 (as the initiator) in order to produce compound [3], then compound [3] reacted with thionyl chloride in benzene to produce compound [4], finally compound [4] reaction with various drugs: cephalexin, amoxicillin, sulfamethizole, elecoxib obtained polymers [5–8]. The structure of synthesized compounds identified by spectral data: fourier transform infrared (FTIR) and proton nuclear magneti
... Show MorePortulacaria afra is a small succulent tree, previously belonging to the Portulacaceae family, but with further studies, the plant transferred to the Didieracea family. P. afra was used as an ornamental, vegetable, and ethnomedicinal plant. Uses of the plant by rural South Africans to treat chronic skin conditions and rashes, alleviate exhaustion, and aid in treating TB and diarrhea have been documented in folklore. According to pharmaceutical research, plant extracts off er a wide range of remedial outcomes, such as antidiabetic, antifungal, antibacterial, anticancer, antioxidant, and anti-infl ammatory. The study aims to determine some bioactive constituents responsible for pharmacological activities and traditional usefulness. Th
... Show MoreThis work was conducted to study the extraction of pelletierine sulphate from Punica granatum L. roots by liquid membrane techniques. Pelletierine sulphate is used widely in medicine. The general behavior of extraction process indicates that pelletierine conversion increased with increasing the number of stages and the discs rotation speed but high rotation speed was not favored because of the increased risk of droplet formation during the operation. The pH of feed and acceptor solution was also important. The results exhibit that the highest pelletierine conversion was obtained when using two stages,(10 rpm) discs speed of stainless steel discs,(pH= 9.5) of feed solution and (pH= 2) of acceptor solution in n-decane. Assuming the existence
... Show MoreWohlfahrtia longicorpuris sp. nov., from Iraq described, illustrated and distinguished from related species. The adults were reared from larvae collected from ulcer of a human face. Wohlfahrtia Brauer and Bergenstam is one of most important genus,which contains 19 species (Pape, 1998), some of these produce myiasis in mammals (Verves,1985).Taxonomic revision of this genus has been carried out by the following authors: Rohdendrof (1956), Zumpt (1965) and Pape (1996).