The provision of openings in serviceable reinforced concrete beams may result in a substantial decline in the beam's capacity and integrity, indicating the necessity of opening strengthening. The present study investigates the experimental response of reinforced concrete T-beams with multiple web-strengthened openings disposed in shear span to static and impact loads. Fourteen RC T-beams were tested in two groups, each of seven beams. The first group was tested under static loading up to failure, while the second group was tested under repeated impact loading until the width of shear cracks reached 0.3 mm. The residual static strengths of the beams subjected to impact loading were then determined. The test variables considered were: number of web openings, the method used to strengthen the member at openings and the height of drop during impact tests. All beams were simply supported with load applied at mid – span. Static results indicated that T-beams with four and six un-strengthened web circular openings whose diameter is 48% of the web depth have strength capacities less than those without openings by 30% and 41%, respectively. However, strengthening of webs results in an increase in the strength capacities ranging between 27% and 92%, depending on the type of strengthening. Impact results indicated that the beam with four openings did not show a remarkable increase in the maximum mid-span deflection compared with the solid beam, while that with six openings showed an increase in the maximum mid-span deflections by about 75% greater than the maximum mid-span deflection of the solid beam. Strengthening of specimens could overcome the increase in deflections.
Free radicals are reactive compounds, their excessive production is considered to be an important cause of oxidative damage in biomolecules causing degenerative diseases. Polyphenols are one of the most important groups of secondary metabolites of plants, which have an antioxidant activity depending on their properties as hydrogen donors. Echinops polyceras Boiss. (Asteraceae) is one of Echinops genus species that spread in Syria, Lebanon, and Palestine. Phytochemicals found in this species leaves have been extracted with gradient polarity solvents, and primary screening of the secondary metabolites was established. The phenolic compounds and flavonoids contents were determined. The free radicals scavenging activity was evaluated for all
... Show MoreThe international business environment faces many challenges, including the intensity of competition, the speed of expansion, and control of the market. This leads to its shadow on the local business environment, which prompted many economic units to adopt modern strategies, including mergers and acquisitions, for expansion and prosperity. The research was conducted to verify the role of internal audit in the governance of strategy operations (Mergers and acquisitions) and its reflection on management decisions and making them efficient and effective. Internal auditing is the independent variable related to the other variable, the governance of strategic operations and its impact on management decisions for strategic operations as a depende
... Show MoreThe aim: Infection with the hepatitis B virus (HBV) caused by blood transfusion is a big problem throughout the world. The aim of study is to determine the faster and more accurate methods for detection of hepatitis B infections by serological screening and PCR- amplification. Materials and methods: A total of 140528 donors were tested for HBsAg and total anti-HBc from January to October 2021 in Iraq’s National Blood Transfusion Center; however, only 100 samples with HBsAg (-) and anti-HBc (+) were collected and tested for HBV DNA using quantitative real-time PCR. Results: From 2015 to 2021, the percentage of HBsAg positive donors was 0.33 percent in 2015, 0.32 percent in 2016, 0.30 percent in 2017, 0.28 percent in 2018, 0.23 pe
... Show MoreSilica-based mesoporous materials are a class of porous materials with unique characteristics such as ordered pore structure, large surface area, and large pore volume. This review covers the different types of porous material (zeolite and mesoporous) and the physical properties of mesoporous materials that make them valuable in industry. Mesoporous materials can be divided into two groups: silica-based mesoporous materials and non-silica-based mesoporous materials. The most well-known family of silica-based mesoporous materials is the Mesoporous Molecular Sieves family, which attracts attention because of its beneficial properties. The family includes three members that are differentiated based on their pore arrangement. In this review,
... Show MoreBackground: Polycystic ovary syndrome is among the leading causes of fertility-related problems and menstrual irregularities in women of reproductive age. The granulosa cells of the developing pre-antral and antral follicles produce inhibin B, which triggers chemical responses in the ovaries. Inhibin B is most often observed in the follicular phase when levels peak early and then decline over time Objectives: This study was designed to investigate the role of serum inhibin B and the Luteinizing Hormone / Follicle Stimulating Hormone ratio in differentiation between the different phenotypes of polycystic ovary syndrome as well as to define the predominant PCOS phenotype. Methods: This cross-sectional research was conducted in the
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