Preferred Language
Articles
/
ExcQs44BVTCNdQwCBVcS
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-iMPP produces a wider half-absorption bandwidth compared to the conventional homogeneous double-layer MPP. The absorption bandwidth to higher frequencies can be effectively controlled by reducing the air cavity between the iMPPs and to the lower frequencies by increasing the back cavity depth at the second layer.

Scopus Clarivate Crossref
View Publication
Publication Date
Tue Jul 02 2013
Journal Name
Journal Of Baghdad College Of Dentistry
Local Drug Delivery Systems for Treating Periodontal Diseases: A Review of Literature
...Show More Authors

Publication Date
Wed Mar 18 2020
Journal Name
Baghdad Science Journal
Synthesis and Characterization of Gold Nanoparticles by Aluminum as a Reducing Agent
...Show More Authors

             The synthesis of nanoparticles (GNPs) from the reduction of HAuCl4 .3H2O by aluminum metal was obtained in aqueous solution with the use of Arabic gum as a stabilizing agent. The GNPs were characterized by TEM, AFM and Zeta potential spectroscopy. The reduction process was monitored over time by measuring ultraviolet spectra at a range of λ 520-525 nm. Also the color changes from yellow to ruby red, shape and size of GNP was studied by TEM. Shape was spherical and the size of particles was (12-17.5) nm. The best results were obtained at pH 6.

View Publication Preview PDF
Scopus (4)
Crossref (2)
Scopus Crossref
Publication Date
Thu Jul 03 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Local drug delivery systems for treating periodontal diseases (A review of literature)
...Show More Authors

In this review of literature, the light will be concentrated on the local drugs delivery systems for treating the periodontal diseases. Principles, types, advantages and indications of each type will be discussed in this paper.

View Publication Preview PDF
Publication Date
Wed Mar 04 2015
Journal Name
Environmental Earth Sciences
Isotopic study of water resources in a semi-arid region, western Iraq
...Show More Authors

View Publication
Scopus (36)
Crossref (23)
Scopus Clarivate Crossref
Publication Date
Thu Jul 06 2023
Journal Name
Science And Technology Indonesia
Preparation of Al2O3 /PVA Nanocomposite Thin Films by a Plasma Jet Method
...Show More Authors

Alumina thin films have significant applications in the areas of optoelectronics, optics, electrical insulators, sensors and tribology. The novel aspect of this work is that the homogeneous alumina thin films were prepared in several stages to generate a plasma jet. In this paper, aluminium nanoparticles suspended in vinyl alcohol were prepared using exploding wire plasma. TEM analysis was used to determine the size and shape of particles in aluminium and vinyl alcohol suspensions; the TEM images showed that the particle size is 17.2 nm. Aluminium/poly vinyl alcohol (Al/PVA) thin films were prepared using this suspension on quartz substrate by plasma jet technique at room temperature with an argon gas flow rate of 1 L/min. The Al/PV

... Show More
View Publication
Scopus (3)
Crossref (2)
Scopus Crossref
Publication Date
Thu Dec 01 2022
Journal Name
WiadomoĊ›ci Lekarskie
EVALUATION OF TWO CRYOPROTECTANTS USED IN A NEW HUMAN SPERM CRYOPRESERVATION TECHNIQUE
...Show More Authors

The aim: To examine the efficiency of different concentrations of Dimethyl sulfoxide (DMSO) and glycerol as a cytoprotectants in protection of human sperms during cryopres¬ervation in this technique. Materials and methods: Thirty oligozoospermic semen samples were used in this study. Samples diagnosed according to WHO 2010 criteria. Sheep’s ovarian follicles obtained from local slaughterhouse and prepared by slicing the ovaries and evacuating the follicular fluid and oocyte. Each semen sample divided into six equal parts, and diluted 1:1 with cryosolution contains 5%, 10%, 15% DMSO or glycerol and injected within the emptied follicles. After freezing and thawing, the semen mixture aspired outside the follicles and sperm concentr

... Show More
View Publication
Scopus Crossref
Publication Date
Thu Jun 30 2011
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
A PARTICULAR SOLUTION OF THE TWO AND THREE DIMENSIONAL TRANSIENT DIFFUSION EQUATIONS
...Show More Authors

A particular solution of the two and three dimensional unsteady state thermal or mass diffusion equation is obtained by introducing a combination of variables of the form,
η = (x+y) / √ct , and η = (x+y+z) / √ct, for two and three dimensional equations
respectively. And the corresponding solutions are,
θ (t,x,y) = θ0 erfc (x+y)/√8ct and θ( t,x,y,z) =θ0 erfc (x+y+z/√12ct)

View Publication Preview PDF
Publication Date
Sat Jun 01 2024
Journal Name
Journal Of The College Of Languages
A Phono-stylistic Analysis of Utterance Stress in Steve Harvey's talk show
...Show More Authors

patterns of utterance stress in discourse direct attention to specific themes and reactions, controlling the flow and coherence of conversation. this study examines the utterance stress in Steve Harvey's selected episodes from a phono-stylistic perspective. this study is hoped to improve understanding of linguistic mechanism in talk show communication, highlighting the importance of phonetic features in transmitting meaning and increasing broadcast conversation participation. the researcher concentrates on the types of focus functions of utterance stress of some episodes available on YouTube. to conduct the analysis, the researcher adopts (Carr, 2013; Davenport& Hannahs 2005) to analyze utterance stress and Leech and Short (2007

... Show More
Crossref
Publication Date
Mon Jan 02 2023
Journal Name
International Journal Of Nonlinear Analysis And Applications
Diagnostic COVID-19 based on chest imaging of COVID-19: A survey
...Show More Authors

Publication Date
Sat Jun 06 2020
Journal Name
Journal Of The College Of Education For Women
A Critical Pragmatic Study of Racism as Conceptualized in the Glorious Quran
...Show More Authors

Racism changes its meaning, shape, purpose or function according to various factors such as time, place, motives, and backgrounds; among others. It seems, however, to have deep roots back in the history of mankind. Such a concept stems from a perceived difference with the other. It is fed by the feeling of being hierarchically superior in opposition to another party that is depicted as inferior. Since ancient times, racism is disguised in different forms and manifests itself on various levels. It is a truism that this ideology can be best presented via language.

Due to its negative implication, racism lends itself to a critical kind of research.  As such, this paper is a critical pragmatic investigation for this phenomenon a

... Show More
View Publication Preview PDF
Crossref (2)
Crossref