Preferred Language
Articles
/
9Rc5e44BVTCNdQwCC0lc
Inducing Frictional Force to Enhance the Transient Response in Beams
...Show More Authors

This paper studies the effect of contact areas on the transient response of mechanical structures. Precisely, it investigates replacing the ordinary beam of a structure by two beams of half the thickness, which are joined by bolts. The response of these beams is controlled by adjusting the tightening of the connecting bolts and hence changing the magnitude of the induced frictional force between the two beams which affect the beams damping capacity. A cantilever of two beams joined together by bolts has been investigated numerically and experimentally. The numerical analysis was performed using ANSYS-Workbench version 17.2. A good agreement between the numerical and experimental results has been obtained. In general, results showed that the two beams vibrate independently when the bolts were loosed and the structure stiffness is about 20 N/m and the damping ratio is about 0.008. With increasing the bolts tightening, the stiffness and the damping ratio of the structure were also increased till they reach their maximum values when the tightening force equals to 8330 N, where the structure now has stiffness equals to 88 N/m and the damping ratio is about 0.062. Beyond this force value, increasing the bolts tightening has no effect on stiffness of the structure while the damping ratio is decreased until it returned to 0.008 when the bolts tightening becomes immense and the beams behave as one beam of double thickness.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Sep 02 2012
Journal Name
Baghdad Science Journal
Effect of Aquatic, Alcoholic and Oily Extracts of Cocos nucifera L.on the Growth of Certain Pathogenic Bacteria Isolated from Wounds and Burns Infections
...Show More Authors

Three types of extracts ( aquatic, alcoholic, and oily ) were prepared from the fruits of coconuts, and a series of chemical tests were conducted in addition to the use of the FTIR equipment to determine the active locations in the prepared extracts. The results indicated the presence of active compounds (tannins, saponins, flavonoids, turbines and steroids) in the extracts prepared from the fruits of coconuts, also the antimicrobial capability of these extracts were tested on pathogenic bacteria isolated from wounds and burns infections cases. The results proved that the concentration 80 mg/ml of the aquatic extract is the minimum inhibitory concentration for the microbes: Proteus vulgaris and Pseudomonas fluorescence, while the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2012
Journal Name
Baghdad Science Journal
Effect of Aquatic, Alcoholic and Oily Extracts of Cocos nucifera L.on the Growth of Certain Pathogenic Bacteria Isolated from Wounds and Burns Infections
...Show More Authors

Publication Date
Sun Aug 01 2021
Journal Name
Journal Of Environmental Chemical Engineering
Green synthesis for novel sorbent of sand coated with (Ca/Al)-layered double hydroxide for the removal of toxic dye from aqueous environment
...Show More Authors

Crossref (32)
Crossref
Publication Date
Sun Jan 01 2017
Journal Name
International Journal Of Chem Tech Research
Synthesis of New Selective Electrodes for the Determination of Metronidazole Benzoate (MNZB) Based on a Molecularly Imprinted Polymer Combined With Poly Vinyl Chloride
...Show More Authors

Publication Date
Wed Dec 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Evaluation the Effect of Addition of Plasma Treated Polypropylene Fiber and Silanized Silicon Dioxide Nanoparticles Composite on Some Properties of Heat-Polymerized Polymethylmethacrylate
...Show More Authors


Background: Polymethylmethacrylate (PMMA) is the most ‎commonly used m‏aterial in denture construction. This material is ‎far from ideal in fulfilling the‎ mechanical requirements, like low impact and transverse strength and poor thermal conductivity are present in this material. The purpose of this study was to study the effect of addition a composite which include 1%wt silanized silicone dioxide nano fillers (SiO2) and 1wt% oxygen plasma treated polypropylene fiber (PP) on some properties of heat cured acrylic resin denture base material (PMMA). Materials and methods: One hund‏red (100) prepared specimens were divided into five groups according to the tests, each group consisted of 20 specimens and t

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Isolation of some active materials and aqueous, alcoholic and oil seed extracts of the plant (Curcuma longa (and study Antibacterial and anticancer activity
...Show More Authors

This study included isolation of some active materials from Curcuma longa such as tannins, saponins and volatile oils with percentage of 59%, 31%, and 9% respectively. Also the study included the determination of minerals in Curcuma longa such as " Na, Ca and K" using Flame photometer. The concentrations of these minerals were (14 ppm),(10 ppm) and )76 ppm) respectively. The anti-bacterial activity study was performed for the active materials isolated from Curcuma longa against two genus of pathogenic bacteria, Escherichia Coli and Staphylococcus aurous by using agar-well diffusion method. It appeared from this study that all of the extraction have inhibitory effect on bacteria was used. The inhibition zone diameter varies with

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Dec 30 2018
Journal Name
Baghdad Science Journal
Concentration of lead and the proportion of sedimentary organic matter , clay minerals , non-clay minerals and soil gradation , City of Nasiriyah , Southern Iraq
...Show More Authors

The present research included sampling and analysis of 41 soil samples , the samples cover various areas of Nasiriyah city (industrial,commercial,residential and agricultural ) to estimate pollution levels of lead element and determine the correlation between lead concentration and natural factors in soil which represent sedimentary organic matter content, granular gradient, clay minerals and non-clay minerals . The results of the current study showed that the average concentration of lead in the soil samples was 61.12 ppm , it was noticed an increase in the concentration of lead in environmental components in the area of this study especially in residential , industrial and commercial location and the impact of natural factors of the so

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jun 30 2023
Journal Name
Biomedicin
Antibacterial action of AgNPs produced from different isolates Gram positive and Gram-negative bacteria on biofilm of Klebsiella pneumoniae isolated from the RTI
...Show More Authors

Silver nanoparticles synthesized by different species

Preview PDF
Publication Date
Wed Dec 29 2021
Journal Name
Journal Of The College Of Education For Women
Difficulties of Understanding English Breaking News Headlines by Iraqi EFL Learners at the University Level: عبد القادر طالب نعيم, و جمعة قادر حسين
...Show More Authors

Understanding breaking news necessitates a special attention, since they are written with a special style. The study aims at identifying the difficulties faced by the Iraqi university EFL learners in comprehending English breaking news. The study included 10 fourth year students enrolled at the Department of English, College of Education for Humanities, University of Anbar. Thus, a questionnaire as a research instrument, was sent online to the students. The questionnaire points were related to the identification of difficulties faced by the learners in comprehending English breaking news. The data of the study were (10) headlines selected purposively from Euronews website. The data were qualitatively analyzed based on quantifying the qua

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Feb 22 2021
Journal Name
Educatum Journal Of Science, Mathematics And Technology
Effect of ammonia/gallium ratio and growth temperature towards the surface morphology of semi-polar GaN grown on m-plane sapphire via MOCVD
...Show More Authors

A single-crystalline semi-polar gallium nitride (11-22) was grown on m-plane (10-10) sapphire substrate by metal organic chemical vapor deposition. Three-step approach was introduced to investigate the grain size evolution for semi-polar (11-22) GaN. Such approach was achieved due to the optimized gallium to ammonia ratio and temperature variations, which led to high quality (11-22) oriented gallium nitride epilayers. The full width at half maximum values along (-1-123) and (1-100) planes for the overgrowth temperature of 1080°C were found to be as low as 0.37° and 0.49°, respectively. This was an indication of the enhanced coalescence and reduction in root mean square roughness as seen by atomic force microscopy. Surface analysi

... Show More
View Publication Preview PDF
Crossref