Double-layer micro-perforated panels (MPPs) have been studied extensively as sound absorption systems to increase the absorption performance of single-layer MPPs. However, existing proposed models indicate that there is still room for improvement regarding the frequency bands of absorption for the double-layer MPP. This study presents a double-layer MPP formed with two single MPPs with inhomogeneous perforation backed by multiple cavities of varying depths. The theoretical formulation is developed using the electrical equivalent circuit method to calculate the absorption coefficient under a normal incident sound. The simulation results show that the proposed model can produce absorption coefficient with wider absorption bandwidth compared w

During COVID-19, wearing a mask was globally mandated in various workplaces, departments, and offices. New deep learning convolutional neural network (CNN) based classifications were proposed to increase the validation accuracy of face mask detection. This work introduces a face mask model that is able to recognize whether a person is wearing mask or not. The proposed model has two stages to detect and recognize the face mask; at the first stage, the Haar cascade detector is used to detect the face, while at the second stage, the proposed CNN model is used as a classification model that is built from scratch. The experiment was applied on masked faces (MAFA) dataset with images of 160x160 pixels size and RGB color. The model achieve

The antioxidant and antibacterial activities of ethanolic extract and phenolic compounds extract of Lemon balm (Melissa officinalis) and Oregano (Oreganum vulgare) plants were studied; the phenolic content and the relationship between these compounds and the above activities were also investigated. The results showed that the Lemon balm had the highest phenolic content (56.5% mg g) and the phenolic content of Oregano was twice lower than Lemon balm. Lemon balm has the highest antioxidant activity which causes lipid peroxidation inhibition activity of linoleic acid (90.5%), this activity was more than ?-tocopherole antioxidant activity (79.3 %). It was found that the main source of antioxidant activity o

THE Schiff base reaction played an important role of the condensation reaction between 2-aminophenol and Glyoxylic acid in the presence of calculated amounts of KOH as a catalyst. The reaction has been carried out in ethanol under reflux and stirring condition for 3.5 hrs. All syntheses were carried out under hydrogen gas forming a new potassium (E)-1-hydroxy-2-(2-hydroxyphenylimino)ethanolate ligand type [NO2]. The ligand of the general formula K2[Mn(L2)] type and its Mnп complex K2[Mn(N2O4)] type, has been characterized by spectroscopic methods (F.T-I.R. and U.V-Vis.), elemental analysis (C.H.N) metal content, magnetic susceptibility measurement, Thin-layer chromatography (T.L.C), X-RD powder diffraction, 1H-NMR, 13C-NMR molar conductanc

A new carbonyl complexes of triazole and oxadiazole were synthesized. These complexes were identified and their structural geometric were suggested by using FT-IR and UV-Vis spectra, conductivity measurements and other chemical and physical properties. The spectra data (FT-IR, UV, Vis.) with the substantial aid of group theoretical calculations gave so many evidences for the proposed geometries and the type of bonding of these compounds

Background : Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of upper extremities and Open carpal tunnel release is the most frequent surgical procedure and the gold standard for cases that do not respond to conservative treatment. Aims :This study is used to evaluate the functional outcome of limited palmar mini-incision of carpal tunnel release. This study aims to determine the safety and symptomatic and functional efficacy of median nerve decompression with limited incision in carpal tunnel syndrome surgery. Patients and methods:Carpal tunnel release with a 1.5-2 cm limited palmar incision was performed on 20 patients. Patients were evaluated initially at one month after treatment according to symptom severity

Small ring heterocycles containing nitrogen and sulfur have been under investigation for a long time because of their important medicinal properties. Among the wide range of heterocycles explored to develop pharmaceutically important molecules, thiadiazoles had played an important role in medicinal chemistry. A survey of literature had shown that compounds having thiadiazole nucleus possess a broad range of biological activities such as anti-inflammatory (1), antibacterial (2), and antifungal activities (3). Thiazine-4-one and their derivatives are import classes of compounds in organic and medicinal chemistry. The thiazine-4-one ring system is a core structure in various synthetic pharmaceutical agents, displaying a broad spectrum of biolo

In this work involved prepared of several new 1-cyclopentene-1,2-dicarboxylimide linked to oxadiazole and benzothiazole moiety were synthesized by two steps: The first step 2-amino-substituted-1,3,4-oxadiazoles and substituted-2-aminobenzothiazole were reaction with 1-cyclopentene-1,2-dicarboxyl anhydride producing N-( 5- substituted-1,3,4-oxadiazole-2-yl)-1-cyclopentene-1,2-dicarboxyl amic acids and N-(Substitutedbenzothiazole-2-yl)-1-cyclopentene-1,2-dicarboxyl amic acids which in turn were dehydrated in the second step via fusion method to afford he desirable N-(5-substituted-1,3,4-oxadiazole-2-yl)-1-cyclopentene-1,2-dicarboxylimides and N-(Substituted benzothiazole-2-yl)1-cyclopentene-1,2-dicarboxylimides respectively. Struct