Preferred Language
Articles
/
FRgXyZgBVTCNdQwCHMHn
Influence of Solar and Geomagnetic Activity on the Ionospheric Sporadic-E Layer Over Baghdad
...Show More Authors
Abstract<p>This study examines the monthly mean diurnal variations of the ionospheric sporadic E (Es) layer’s critical frequency (<italic>foEs</italic>) and virtual height (<italic>h′Es</italic>) above Baghdad city (latitude 33.3˚N, longitude 44.4˚E) during Solar Cycle 22 (1988–1995). The analysis examines their correlation with solar activity, represented by sunspot numbers, and geomagnetic disturbances, particularly during the descending phase of the cycle. The findings revealed that <italic>foEs</italic> values were the highest during the solar maximum years (1989–1991), aligning with increased sunspot numbers and geomagnetic activity due to coronal mass ejections (CMEs). However, during the declining phase (1993–1994), <italic>foEs</italic> exhibited a stronger dependence on geomagnetic disturbances from the recurrent solar wind structure Stream Interaction Regions (SIRs), suggesting that transient interplanetary space phenomena play a significant role in Eslayer dynamics. Additionally, <italic>h′Es</italic> demonstrated a distinct two-peak diurnal pattern, with maxima occurring in the morning local time (0800–0900 LT) (UCT+3) and late afternoon (1600–1800 LT). Seasonal variations affected peak timing, with summer months experiencing a delayed second peak compared to winter and autumn. The highest <italic>h′Es</italic> values were observed in 1989 and 1994, reflecting the dual influence of solar maximum conditions and increased geomagnetic activity accompanied by minor and moderate disturbances during the descending phase of the cycle. These results highlighted the complex interplay between solar and geomagnetic influences on Es-layer variability.</p>
Scopus Crossref
View Publication
Publication Date
Sat Jun 15 2019
Journal Name
Agriculture
Cover Crop Influence on Soil Enzymes and Selected Chemical Parameters for a Claypan Corn–Soybean Rotation
...Show More Authors

Cover crops (CC) improve soil quality, including soil microbial enzymatic activities and soil chemical parameters. Scientific studies conducted in research centers have shown positive effects of CC on soil enzymatic activities; however, studies conducted in farmer fields are lacking in the literature. The objective of this study was to quantify CC effects on soil microbial enzymatic activities (β-glucosidase, β-glucosaminidase, fluorescein diacetate hydrolase, and dehydrogenase) under a corn (Zea mays L.)–soybean (Glycine max (L.) Merr.) rotation. The study was conducted in 2016 and 2018 in Chariton County, Missouri, where CC were first established in 2012. All tested soil enzyme levels were significantly different between 2016 and 2018

... Show More
View Publication
Scopus (23)
Crossref (19)
Scopus Clarivate Crossref
Publication Date
Wed Apr 01 2020
Journal Name
Applied Acoustics
Wideband sound absorption of a double-layer microperforated panel with inhomogeneous perforation
...Show More Authors

Micro-perforated panel (MPP) absorber is increasingly gaining popularity as an alternative sound absorber in buildings compared to the well-known synthetic porous materials. A single MPP has a typical feature of a Helmholtz resonator with a high amplitude of absorption but a narrow absorption frequency bandwidth. To improve the bandwidth, a single MPP can be cascaded with another single MPP to form a double-layer MPP. This paper proposes the introduction of inhomogeneous perforation in the double-layer MPP system (DL-iMPP) to enhance the absorption bandwidth of a double-layer MPP. Mathematical models are proposed using the equivalent electrical circuit model and are validated with experiments with good agreement. It is revealed that the DL-

... Show More
View Publication
Scopus (66)
Crossref (51)
Scopus Clarivate Crossref
Publication Date
Thu Jun 01 2023
Journal Name
Iraqi Journal Of Physics
Preparation of SiO2:TiO2 for High-Performance Double Layer Anti-Reflection Coating
...Show More Authors

        In this work, an anti-reflection coating was prepared in the region (400-1000) nm of wavelength, with a double layer of silicon dioxide (SiO2) as an inner layer and the second layer of the mixture (SiO2) and titanium dioxide (TiO2) with certain ratios, as an outer layer using the chemical spraying method with a number of 6 sprays of layer SiO2 and 12 sprays of layer SiO2 - TiO2. Using the method of chemical spraying deposited on the glass as a substrate with a different number of sprays of SiO2, and a fixed number of TiO2-SiO2. The optical and structural properties were determined using UV-Vis spectroscopy and atomic force mi

... Show More
View Publication Preview PDF
Crossref (7)
Crossref
Publication Date
Fri Sep 01 2023
Journal Name
Iraqi Journal Of Physics
Study of the Structural, Optical, and Morphological Properties of SnO2 Nanofilms under the Influence of Gamma Rays
...Show More Authors

This study reports the fabrication of tin oxide (SnO2) thin films using pulsed laser deposition (PLD). The effect of 60Co (300, 900, and 1200 Gy) gamma radiation on the structural, morphological, and optical features is systematically demonstrated using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and ultraviolet-visible light analysis (UV-Vis), respectively In XRD tests, the size of the crystallites decreased from 45.5 to 40.8 nm for the control samples and from 1200 Gy to 60Co for the irradiated samples. Using FESEM analysis, the particle diameter revealed a similar trend to that attained using XRD; in particular, the average diameters were 93.8 and

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Economics And Administrative Sciences
The Effect of Knowledge Upgrading on Business Continuity:A Field Research in Private Colleges and Universities in Baghdad
...Show More Authors

The research aims to study the effect of knowledge upgrade on business continuity in private colleges and universities in Baghdad. The research problem is summarized in the main question (were the academic leaders able to employ knowledge upgrading to enhance business continuity). The most important of this sector were the universities and the private college in the city of Baghdad as a field for this research, the researchers conducted a field visit to (10) universities or private colleges, the research sample consisted of (177) individuals from the deans of colleges and their assistants, as well as heads of scientific and administrative departments. The data was analyzed and the hypotheses were tested using the appropriate statistical

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Dec 12 2003
Journal Name
Iraqi Journal Of Laser
The Influence of Short Wavelength Laser on the Pupae Development of the Old World Screw- Worm Fly (OWSWF) Chrysomya bezziana Villeneuve (Diptera: Calliphoridae)
...Show More Authors

The biological effects of pulsed N2-laser on the old world screw-worm fly, Chrysomya bezziana Villeneuve in the pupal stage were investigated. Different laser parameters were involved in this work. The old pupae of 1, 2, 3, 4 and 5 days were exposed to laser radiation during 10, 30 and 60 second with repetition rate 10, 20 and 30 pulse/second. The percent of normal adults emergence (female and male) was investigated. The results showed that the adults emergence was highly decreased as the repetition rate and exposure time increased when the pupae irradiated for 1, 2 and 3 days old as compared with 4 and 5 days. The results also indicated that the pupal period was significantly increased of irradiated pupae for 1, 2, 3 and 4 days old, whi

... Show More
View Publication Preview PDF
Publication Date
Sun May 19 2024
Journal Name
Basrah Journal Of Agricultural Sciences
Investigation on Field Performance of Plowing and Harvesting Potatoes in Southern Baghdad
...Show More Authors

This field experiment, was conducted to investigate a comparison of two methods for harvesting potatoes: mechanical and handy when using moldboard and chisel plow for primary tillage and three different distances for planting tubers in the rows 15, 25, and 35 cm in silt clay loam soil south of Baghdad. The factorial experiment followed a randomized complete block design with three replications using L.S.D. 5 % and 1 %. Mechanical harvest recorded the best valid potato tubers at 88.78 %, marketable yield of 31.74 ton. ha-1, efficiency lifted 95.68 %, tubers damage index 28.41, speeding up the harvesting process and reducing time and effort. Handy harvest gave the least damage to potato tubers, 6.02 %, and unlifted potato tubers, 4.32 %. Howe

... Show More
Publication Date
Mon May 11 2020
Journal Name
Baghdad Science Journal
Strong Subordination for E -valent Functions Involving the Operator Generalized Srivastava-Attiya
...Show More Authors

Some relations of inclusion and their properties are investigated for functions of type " -valent that involves the generalized operator of Srivastava-Attiya by using the principle of strong differential subordination.

View Publication Preview PDF
Scopus (6)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Wed Aug 30 2023
Journal Name
Al-kindy College Medical Journal
The Impact of using the Internet and Social Media on Sleep in a group of Secondary School Students from Baghdad
...Show More Authors

Background: Insufficient sleep due to excessive media use is linked to decrease physical activity, poor nutrition, obesity, and decreased overall health-related quality of life.

Objectives: To assess the effect of using the internet and social media on the sleep of 4th-stage secondary school students.

Subjects and Methods: Cross-sectional study with the analytic element; for 500 secondary school students, obtained by choosing two schools randomly from each of the six educational directorates, by using a structured questionnaire.

Result: Secondary scho

... Show More
View Publication Preview PDF
Scopus (4)
Crossref (2)
Scopus Crossref
Publication Date
Fri Sep 27 2019
Journal Name
Journal Of Baghdad College Of Dentistry
Salivary vitamin E and uric acid in patients with OLP and healthy individuals
...Show More Authors

Background: Oral Lichen planus (OLP) is a T-cell mediated chronic inflammatory oral mucosal disease of unknown etiology. Recent studies have reported an increased oxidative stress and lipid peroxidation in such patients. This suggests that reactive oxygen species may have a role in the pathogenesis of lichen planus. Oxidative stress in OLP release molecules consisting of granzymes resulting in local tissue damage in the effectors. Antioxidants that can defend against oxidative stress in the body cells include enzymes, as well as non- enzymatic antioxidants, such as melatonin, uric acid, vitamin A and E. Purpose: To study the level of salivary vitamin E and uric acid as antioxidant agents in patients with OLP and compared with healthy con

... Show More
View Publication Preview PDF
Scopus (3)
Crossref (3)
Scopus Crossref