Preferred Language
Articles
/
joe-2040
Numerical Simulation of 3D- Flow Structure and Heat Transfer for Longitudinal Riblet Upstream of Leading Edge Endwall Junction of Nozzle Guide Vane
...Show More Authors

The simulation have been made for  3D flow structure and heat  transfer with and without

longitudinal riblet upstream of leading edge vane endwall junction of first stage nozzle guide vane .The research explores concept of weakening the secondary flows and reducing their harmful effects.Numerical investigation involved examination of the secondary flows ,velocity and heat transfer rates by solving the governing equations (continuity, Navier -stokes and energy equations ) using the known package FLUENT version (12.1).The governing equations were solved for three dimentional, turbulent flowe, incompressible with an appropriate turbulent model (k-ω,SST) .The numerical solution was carried out for 25 models of V-groove riblet with wide ranges of height (h) and space (s). The results indicated that, the riblet endwall junction was a powerful tool for controlling the flow structure, reducing secondary flow formation,and elimination the effect of heat transfer at leading edg and passage . The drag reduction produced by riblet was proportional with their height and space. V-groove riblet with dimension of (h=1.35mm and s=2.26mm) was found to be the most effective in reduction of drag (2.7%) and heat transfer (21%) so it was selected as an optimum dimension of riblet model. The results also showed that the drag reduction produced by riblet was proportional to their size. The riblet model had a great effect in elimination spanwise ,pitchwise velocities ,but strength the streamwise velocity .At leading edge ,the effect of secondary flow was extended up to 23% from span height and 35% upstream leading edge .The riblet model caused an increase in momentom at a region very close to leading edge and to move stagnation point very close to the leading edge.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Sep 19 2022
Journal Name
International Journal Of Biomaterials
Green Biosynthesis of Silver Nanoparticles from Moringa oleifera Leaves and Its Antimicrobial and Cytotoxicity Activities
...Show More Authors

The plant occupied the largest area in the biosynthesis of silver nanoparticles, especially the medicinal plants, and it has shown great potential in biotechnology applications. In this study, green synthesis of silver nanoparticles from Moringa oleifera leaves extract and its antifungal and antitumor activities were investigated. The formation of silver nanoparticles was observed after 1 hour of preparation color changing. The ultraviolet and visible spectrum, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy techniques were used to characterize synthesis particles. Ultraviolet and visible spectroscopy showed a silver surface plasmon resonance band at 434

... Show More
View Publication
Scopus (20)
Crossref (19)
Scopus Clarivate Crossref
Publication Date
Fri Jun 14 2019
Journal Name
Biotechnology Letters
Extracellular biosynthesis of silver nanoparticles from Penicillium italicum and its antioxidant, antimicrobial and cytotoxicity activities
...Show More Authors

View Publication
Scopus (86)
Crossref (85)
Scopus Clarivate Crossref
Publication Date
Sat Jun 25 2022
Journal Name
International Journal Of Drug Delivery Technology
Evaluation of IL17A, FGF21 and CXC12 in Post-menopause Iraqi Sample with Osteoporosis and Osteopenia
...Show More Authors

Osteoporosis (OP) is a systemic skeletal disorder that is characterized by reduced bone mass and micro-architectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture. The most frequent osteoporotic fractures are fractures of the hip, wrist, and spine. The exact causes of OP are still unknown; several factors contribute to the disorder. Subjects and Methods: This study consists of patient groups, this group (Group A) was composed of 80 postmenopausal women with OP and osteopenia and the patient group was subdivided into two group; First group (GroupA1) was composed of 50 postmenopausal women with OP and the second group (Group A2) composed of (30) Postmenopausal Women with oste

... Show More
View Publication
Scopus Crossref
Publication Date
Fri Oct 16 2020
Journal Name
Int J Energy Res
Structural, electronic and optoelectronic properties of AB5C8 (A = Cu/Ag; B = In and C = S, Se and Te) compounds
...Show More Authors

Ternary semiconductors AB5C8 (A = Cu/Ag, B = In and C = S, Se or Te) have been investigated. The CuIn5S8 and AgIn5S8 have been synthesize in cubic spinel structure with space group (Fd3m), whereas CuIn5Se8, AgIn5Se8, CuIn5Te8 and AgIn5Te8 have tetragonal structures with space group P-42m. The relaxed crystal geometry, electrical properties such as electronic band structure and optoelectronic properties are predicted by using full potential method in this work. For the determination of relaxed crystal geometry, the gradient approximation (PBE-GGA) is used. All the studied compounds are semiconductors based on their band structures in agreement with the experimental results, and their bulk moduli are in the range 35 to 69 GPa. Wide absorption

... Show More
Publication Date
Mon Jun 07 2021
Journal Name
Journal Of Molecular Histology
Structural and functional relations between the connective tissue and epithelium of enamel organ and their role during enamel maturation
...Show More Authors

View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Sat Apr 01 2023
Journal Name
Iop Conference Series: Earth And Environmental Science
Effect of Blue and Red LED Light and some Plant Extract on Lettuce Growth and Yield in NFT Technique
...Show More Authors
Abstract<p>This experiment was carried out in the College of Agricultural Engineering Sciences, Univ. of Baghdad, during autumn 2021 growing season to investigate possibility study of increase lettuce antioxidant and biological yield, growing and producing lettuce hydroponically under film technique (NFT) using a globally approved standard solution (Cooper solution), Nested design with three replications adopted in the experiment, each of them included in main plot the first factor, which is LED light (B and R), Then levels of second factor were randomly distributed within each replicate, which included spraying with organic nutrients which was Cymbopogon citratus and Hibiscus sabdariffa at two </p> ... Show More
View Publication Preview PDF
Scopus (3)
Scopus Crossref
Publication Date
Wed Mar 30 2022
Journal Name
Iraqi Journal Of Science
Isolation, Purification, and Characterization of Pecan Nut Lipase and Studying its Affinity towards Pomegranate Extracts and 1, 4-Diacetoxybenzene
...Show More Authors

     This study included partial purification of the lipase enzyme from the karnel of the pecan nut. After applying ion exchange chromatography technique using CM-Cellulose, two lipase isoenzymes were observed with specific activity values of 2.66 and 1.7 units/mg protein. The highest activity of both isoenzymes appeared at the optimum pH values of 8 and 6 and at temperatures of 40 and 50 °C, respectively. A pure single band was obtained by using electrophoresis technique and it was found that the approximate molecular weight was 42 kDa for the two isoenzymes. The study dealt with the preparation of the diester compound 1,4-diacetoxybenzene, which was diagnosed by GC-MS and 1H NMR spectrometry. When studying the inhibitio

... Show More
View Publication Preview PDF
Scopus (3)
Scopus Crossref
Publication Date
Thu Mar 30 2023
Journal Name
College Of Islamic Sciences
Title: Arabic Manuscript, Concepts and Terms and Their Impact on Determining Its Historical beginnings and extension of its existence.
...Show More Authors

Title: Arabic Manuscript, Concepts and Terms and Their Impact on Determining Its Historical beginnings and extension of its existence.

Researcher: Dr. Atallah Madb Hammadi Zubaie.

Bn the name of Allah Most Merciful

The interest in manuscripts and rules  of their investigation and dissemination appeared soon, and the speech in editing terms and concepts appeared in sooner time.  When looking at the classified books  in the Arab manuscripts , we find the books of the first generation  did not allude definition for this term  , but rather  focused on  the importance of manuscripts and their  existence locations, indexing, care, and verification rules. The  reason for this is that the science of Arabic manuscrip

... Show More
View Publication Preview PDF
Publication Date
Fri Jun 24 2022
Journal Name
Iraqi Journal Of Science
Petrology, Mineralogy and Diagenesis of the Rus and Jil Formations (l- Eocene) in Najif and Samawa areas, Southern Iraq
...Show More Authors

This research deals with study of the Petrology and mineralogy of the Rus and Jil Formations at Najif and Al-Muthanna Governorates, Southern Iraq. The Rus Formation consists mainly of evaporites and subordinate carbonates. The evaporites are characterized by nodular structure (compound wispy, wispy, structureless and mosaic structures) with some laminated structure at the studied sections. Compound wispy to wispy structure are the dominant structures. The Jil Formation consists almost entirely of carbonate. The carbonate rocks are dolomitic limestone and dolomite beds, massive, fossiliferous, cavernous sometime friable and bioturbated in its lower part. The Jil Formation contains evaporites as thin beds, sometimes nodular and contains se

... Show More
View Publication Preview PDF
Publication Date
Fri Jun 24 2022
Journal Name
Iraqi Journal Of Science
Petrology, Mineralogy and Diagenesis of the Rus and Jil Formations (l- Eocene) in Najif and Samawa areas, Southern Iraq
...Show More Authors

This research deals with study of the Petrology and mineralogy of the Rus and Jil Formations at Najif and Al-Muthanna Governorates, Southern Iraq. The Rus Formation consists mainly of evaporites and subordinate carbonates. The evaporites are characterized by nodular structure (compound wispy, wispy, structureless and mosaic structures) with some laminated structure at the studied sections. Compound wispy to wispy structure are the dominant structures. The Jil Formation consists almost entirely of carbonate. The carbonate rocks are dolomitic limestone and dolomite beds, massive, fossiliferous, cavernous sometime friable and bioturbated in its lower part. The Jil Formation contains evaporites as thin beds, sometimes nodular and contains se

... Show More
View Publication Preview PDF