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.
The research aims to reveal the methods of visual intertextuality used in the websites of the oriented satellite channel which is Arabic-speaking when addressing normalization with Israel. It also indicates the sources and types of intertextual images, the methodological and semiotic mechanisms for analyzing the intertextuality of news images used on the website of Alhurra satellite channel for the period from 1/6 - 30/8/2022, which included (94) images. The researcher analyzed (37) images with intertextual dimensions, excluding (57) images, which did not carry connotations connected with the inputs and objectives of the research.
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... Show MoreThe use of heavy ions in the treatment of cancer tumors allows for accurate radiation of the tumor with minimal collateral damage that may affect the healthy tissue surrounding the infected tissue. For this purpose, the stopping power and the range to which these particles achieved of Nitrogen (N) in the skin tissue were calculated by programs SRIM (The Stopping and Range of Ions in Matter),(SRIM Dictionary) [1],(CaSP)(Convolution approximation for Swift Particles )[2]which are famous programs to calculate stopping power of material and Bethe formula , in the energy range (1 - 1000) MeV .Then the semi - empirical formulas to calculate the stopping power and range of Nitrogen io
... Show MoreDuring of Experimental result of this work , we found that the change of electrical conductivity proprieties of tin dioxide with the change of gas concentration at temperatures 260oC and 360oC after treatment by photons rays have similar character after treatment isothermally. We found that intensive short duration impulse annealing during the fractions of a second leads to crystallization of the films and to the high values of its gas sensitivity.
The Study addressed the effectiveness of dialogic communication in online public relations with an audience of higher education institutions in the United Arab Emirates. The study aimed to know about the interest extent of higher education institutions through their websites with the elements of dialogic communication in online public relations to communicate with their audience. The researcher used survey methodology and content Analysis tool as an essential tool for collecting information. Some of the important results of the study are: The websites of higher education institutions in terms of indicators of ease of use; the main links on the websites are clearly available on the opening page, there is a map on the websites, reduce depe
... Show MoreKE Sharquie, AA Noaimi, MR Al-Karhi, Journal of Cosmetics, Dermatological Sciences and Applications, 2014 - Cited by 2
Cerebellum is the most important and critical part of the central nervous system, cerebellum is very sensitive to the abnormal changes during the embryological development in its histological structure, the exposure to any infection during embryogenesis produce abnormalities in the cerebellum and behavioral of offspring. In this study we tried to study the ontogenesis of the cerebellum in the embryos of the albino rats and detection the effect of the AgNPs on the ontogenesis of the rat cerebellum after exposure of AgNPs during pregnancy. we used 60 female pregnant rats divided in to three group, each contain 20 female, (G1) treated with 2mg/kg /day suspension of silver nanoparticles (Ag NPs) (G2) treated with 20mg/kg/day AgNPs from first da
... Show MoreBackground: Anti-oxidants are used as supplements to counteract the over production of free radicals in periodontal disease.Co-Q10 functions as an intercellular antioxidant by acting as a primary scavenger of free radicals (FRs) and reactive oxygen species (ROS), this study aimed to evaluate the effect of intra pocket application of perio Q gel (coenzyme Q10) alone and as adjunct to scaling and root planing on the periodontal clinical parameters in the treatment of patients with chronic periodontitis and compare the better improvement on the clinical periodontal parameters among different treatment modalities at 3 and 6 weeks. Materials and methods: A total of 323 sites with pocket depth (5-8) mm in patients with chronic periodontitis were
... Show MoreThe purpose of the current study was to explore the standards that teachers take into consideration when selecting and using assistive technology (AT), in addition to their knowledge and skills in this area. A quantitative, descriptive survey design was used and a convenience sample of 79 teachers of students with intellectual disabilities and autism spectrum disorder (ASD) participated in the current study. Based on the four main areas of the SETT Framework—student, environment, tasks, and tools—, teachers reported a lack consideration for most of the standards in each area. Among other findings, statistically significant differences were found between teachers’ standards of the SETT Framework, with teachers who had previous profe
... Show MoreUrinary tract infections (UTIs) mean microbial pathogens in the urethra or bladder (lower urinary tract). Important risk factors for recurrent UTI include obstruction of the urinary tract, use of a bladder catheter or a suppressed immune system. This study aims to isolate and identify bacteria from patients with TCC-bladder cancer or patients with a negative cystoscope and estimate antibiotic susceptibility patterns and evaluate some of the virulence factors. From a total of 62 patients with TCC-BC or negative cystoscope, only 35 favorable bacterial growths were obtained, including Escherichia coli (UPEC), a significant bacterial isolate, and Stenotrophomonas maltophilia. The percentage of multi drug-resistance bacteria
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