Preferred Language
Articles
/
joe-2019
Theoritical and Experimental Investigation of the Dynamical Behaviour of Complex Configuration Rotors
...Show More Authors

The present work considers an alternative solution for a complex configuration of rotor discs by applying Galerkin Method. The theoretical model consists of elastic shaft carrying number of discs and supported on number of journal bearings. The equation of motion was discretized to finite degree of freedom in terms of the system generalized coordinates. The various effects of the dynamical forces and moments arising from the bearing, discs and shaft were included. Rayleigh beam model is used for analyzing the shaft while the discs are considered rigid . The validity and convergence of the present analysis was carefully checked by comparing with the Finite Element solution. An example of rotor consists of three different size discs and supported by two journal bearing was considered for the numerical solution .The results shows good agreements between the two methods ,where the maximum error not exceeds 5%. The convergence test showed that using few modes (not more than 6) are sufficient for the accurate analysis. The forward and backward whirl was investigated experimentally .The experimental results of a two discs rotor ,show a reasonable agreement where the maximum error not exceeds 11%. The unbalance response, Cambpell diagram, orbit response were plotted .The effects of geometry, disc sizes , location and arrangement on the unbalance response and natural frequencies of three discs rotor were further investigated .

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Nov 01 2020
Journal Name
Journal Of Oral And Maxillofacial Surgery
A Clinicopathologic Review of 21 Cases of Head and Neck Primary Tuberculosis
...Show More Authors

Purpose A diagnosis of tuberculosis (TB) of the head and neck has been a dilemma for clinicians, because the clinical and pathologic features tend to mimic different pathologies. Our study aimed to identify the demographic, clinical, and pathologic features of head and neck TB to help healthcare providers in the early detection of the disease. Materials and Methods We performed a retrospective analysis using the medical archives at the pathology laboratory. Twenty-one patients with a clinical and pathologic diagnosis of head and neck TB were identified from 2010 to 2019. Results The age distribution was broad, with 28.5% of the patients younger than 15 years old. Seven patients had oral TB, with the most common sites affected the labial ves

... Show More
View Publication
Scopus (3)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Thu Aug 31 2023
Journal Name
Materials
Comparative Analysis of Reinforced Asphalt Concrete Overlays: Effects of Thickness and Temperature
...Show More Authors

Reflection cracking in asphalt concrete (AC) overlays is a common form of pavement deterioration that occurs when underlying cracks and joints in the pavement structure propagate through an overlay due to thermal and traffic-induced movement, ultimately degrading the pavement’s lifespan and performance. This study aims to determine how alterations in overlay thickness and temperature conditions, the incorporation of chopped fibers, and the use of geotextiles influence the overlay’s capacity to postpone the occurrence of reflection cracking. To achieve the above objective, a total of 36 prism specimens were prepared and tested using an overlay testing machine (OTM). The variables considered in this study were the thickness of the

... Show More
View Publication Preview PDF
Scopus (6)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Thu Aug 31 2023
Journal Name
Materials
Comparative Analysis of Reinforced Asphalt Concrete Overlays: Effects of Thickness and Temperature
...Show More Authors

Reflection cracking in asphalt concrete (AC) overlays is a common form of pavement deterioration that occurs when underlying cracks and joints in the pavement structure propagate through an overlay due to thermal and traffic-induced movement, ultimately degrading the pavement’s lifespan and performance. This study aims to determine how alterations in overlay thickness and temperature conditions, the incorporation of chopped fibers, and the use of geotextiles influence the overlay’s capacity to postpone the occurrence of reflection cracking. To achieve the above objective, a total of 36 prism specimens were prepared and tested using an overlay testing machine (OTM). The variables considered in this study were the thickness of the

... Show More
Scopus (6)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Tue Jun 01 2021
Journal Name
Iraqi Journal Of Physics
A Study of Crystallographic and DC Electrical Characteristics of PPy/Ag Nanocomposites
...Show More Authors

ABSTRACT: Polypyrrole and polypyrrole / silver nanocomposites were fabricated by in-situ polymerization employing Ammonium Persulphate as an oxidizing agent. Nanocomposites were synthesized by combining polypyrrole and silver nanoparticles in various weight percentages (0.1%, 0.5%, 3%, 5% and 7% wt.). Crystallographic data were collected using X-ray diffraction.  PPy particles were found to have an orthorhombic symmetry. In contrast, PPy/Ag nanocomposites were reported to have monoclinic structure. The crystallite size was determined by XRD using Scherrer equation and considered to be within 49 nm range. DC conductivity of pelletized samples was evaluated in the temperature range of 323.15k to 453.15k. The conductivity displayed an

... Show More
Crossref (1)
Crossref
Publication Date
Sat Apr 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Center of Urban and Regional Planning for postgraduate Studies - University of Baghdad
...Show More Authors

Project deal with the study of the suitability of the planning standards of the select sites for sports facilities for the holy city of Karbala and the extent of convergence and divergence between these standards and points of strength and weakness in each of these standards.

It was found that there was a lack of the   role given to the sports as a kind of luxury does not deserve to spend money and efforts, and was then incorporated with a lot of entertainment services by planners.

أعلى النموذج

<

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Jan 01 2019
Journal Name
World Journal Of Dentistry
Assessment of Implant Stability Changes and Success Rate of Narrow Dental Implants
...Show More Authors

Aims: To assess the success rate and implant stability changes of narrow dental implants (NDIs) during the osseous healing period. Materials and methods: This prospective observational clinical study included 21 patients with narrow alveolar ridge of restricted mesiodistal interdental span who received NDIs. The alveolar ridge width was determined by the ridge mapping technique. Implant stability was measured using Periotest® M immediately after implant insertion then after 4 weeks, 8 weeks and 12 weeks postoperatively. The outcome variables were success rate and implant stability changes during the healing period. The statistical analysis included one-way analysis of variance (ANOVA) and Tukey\'s multiple comparisons test, values < 0.05 w

... Show More
View Publication
Scopus Crossref
Publication Date
Thu Mar 30 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Synthesis of Schiff Bases of Benzaldehyde and Salicylaldehyde as Anti-inflammatory Agents
...Show More Authors

Three Schiff bases from Benzaldehyde and Salicylaldehyde have been synthesized (A, 1and 2) and two of them (1and 2) have been tested for anti-inflammatory activity. The p-aminobenzene sulfonamide has been synthesized from acetanilide through the addition of excess chlorosulfonic acid then concentrated ammonia solution; Schiff base of this derivative (2) exhibited good level of activity against egg-white induced edema in rat hind paw, while the other tested derivative exhibited no activity.

Key words: Schiff bases, sulfonamide derivatives, salicylaldehyde

View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Mon Jan 04 2021
Journal Name
Medico-legal Update
Study of Production and Characterization of Laccase Enzyme from Klebsiellapneumoniae K7 Isolate
...Show More Authors

Sixty four local isolated of Klebsiella spp. have been isolated from environment samples (soil and water). These isolates were identified and diagnosis according to phenotype and biochemical tests. These isolates were subjected to primary and secondary screening, to select the isolate with the highest laccase activity. Fifteen isolates chosen from primary screening for screening their enzyme activity in secondary screening. It has been found the Klebsiella(K7) has the highest productivity of the enzyme (12 Unit/ml).Klebsiella(K7) isolate was diagnosis by Vitak 2 system, it was identified asK. pneumonia. The laccase purified was characterization, the experiments showed that: The molecular weight of laccase was 120KD and the optimum pH for th

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Sep 30 2015
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Problems of Heavy Oil Transportation in Pipelines And Reduction of High Viscosity
...Show More Authors

Drag has long been identified as the main reason for the loss of energy in fluid transmission like pipelines and other similar transportation channels. The main contributor to this drag is the viscosity as well as friction against the pipe walls, which will results in more pumping power consumption.

   The aim in this study was first to understand the role of additives in the viscosity reduction and secondly to evaluate the drag reduction efficiency when blending with different solvents.

   This research investigated flow increase (%FI) in heavy oil at different flow rates (2 to 10 m3/hr) in two pipes (0.0381 m & 0.0508 m) ID By using different additives (toluene and naphtha) with different concent

... Show More
View Publication Preview PDF
Publication Date
Thu Dec 18 2025
Journal Name
Ishraqat Tanmawia
Formation Engineering and Pedagogy of E-Learning in Light of Corona Pandemic
...Show More Authors

View Publication