In this study, the effect of glass fiber reinforced polymer (GFRP) section and compressive strength of concrete in composite beams under static and low velocity impact loads was examined. Modeling was performed and the obtained results were compared with the test results and their compatibility was evaluated. Experimental tests of four composite beams were carried out, where two of them are control specimen with 20 MPa compressive strength of concrete deck slab and 50 MPa for other. Bending characteristics were affected by the strength of concrete under impact loading case, as it increased maximum impact force and damping time at a ratio of 59% and reduced the damping ratio by 47% compared to the reference hybrid beam. Under stat
... Show MoreNear-ideal p-CdS/n-Si heterojunction band edge lineup has been investigated for the first time with aid of I-V and C-V measurements. The heterojunction was manufactured by deposition of CdS films prepared by chemical spray pyrolysis technique (CSP) on monocrystalline n-type silicon. The experimental data of the conduction band offset Ec and valence band offset Ec were compared with theoretical values. The band offset Ec=530meV and Ev=770meV obtained at 300K. The energy band diagram of p-CdS/n-Si HJ was constructed. C-V measurements depict that the junction was an abrupt type and the built-in voltage was determined from C-2-V plot
Burdock ( Arctium lappa), is among the most popular plants in traditional medicine and it is associated with several biological effects. Literature survey revealed the presence of phenylpropanoid compounds .The most widespread are hydroxycinnamic acids ( mainly caffeic acid and chlorogenic acid) and lignans (mainly arctiin and arctigenin). This work will confirm the presence of these compounds in Arctium lappa, cultivated in Iraq, in both root and leaf samples. The dried plant samples were extracted by soxhlet with 80% methanol then separated the main constituents by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Identification of the isolated compounds wa
... Show MoreOptoelectronic devices, widely used in high energy and nuclear physics applications, suffer severe radiation damage that leads to degradations in its efficiency. In this paper, the influence of gamma radiation (137Ce source) and beta radiation (90Sr source) on the photoelectric parameters of the Si solar cell, based on the I–V characterization at different irradiation exposer, has been studied. The penetrating radiation produces defects in the base material, may be activated during its lifetime, becoming traps for electron–hole pairs produced optically and, this will, decrease the efficiency of the solar cell. The main objective of the paper is to study and measure changes in the I–V characteristics of solar cells, such as efficienc
... Show MoreThe present study was conducted to determine the optimum conditions required for lipase enzyme activity extracted from germinated sunflower seeds, including temperature, pH, agitation, time of incubation, enzyme concentration, substrate type, and concentrations of mineral salts and EDTA. Optimum pH, temperature and time of incubation required for lipase stability were also determined. The results showede optimum lipase activity (3.251U/ml) wasund at 30 ÌŠC and pH 7 after 20 minutes of incubation when using 1 ml lipase enzyme with 0.02 ml of CaCl2 (10 mM) at 100 rpm of agitation and in the presence of olive oil as the substrate for enzyme reaction. EDTA appeared to have inhibitory effects, while Ca+2 and Mg+2 have stimulatory effec
... Show MoreBackground: Biologic mechanisms of the form-function interaction are one of important component of orthodontic diagnosis. The purpose of this study is to search for the statistical associations between natural postural and craniofacial morphologic variables of the head. Materials and methods: The sample comprised natural head posture (NHP) cephalograms of 90 subjects, aged 18 to 25 years. Interpretation of the facial structure was made by using both intracranial and the extra-cranial reference lines in AutoCAD computer program. Results The measures of anteroposterior maxillary position, SNA showed a low negative correlations with the anterior cranial base angulation to true vertical (SN.Ver) and with the cranio-cervical position of the head
... Show MoreBackground: Lateral cephalometric radiography is commonly used as a standard tool in orthodontic assessment and treatment planning. This study aimed to determine the tongue and surrounding space area in a sample of Iraqi adults with class I dental and skeletal pattern. Materials and methods: The study included thirty healthy subjects (15 males and 15 females) with an age ranged between 23-34 years and class I dental and skeletal pattern with no history of any sleep related disorders. The assessed cephalometric measurement included length and height of the tongue and position of hyoid bone from cervical line. Descriptive statistics were obtained for the data. Genders difference was evaluated by independent sample t-test. Results: There wer
... Show MoreThe aim of this study is to recognize the influence of model of active thinking in achievement ofeighth grade students andtheir visual thinking in science.The finds of this research show the superiority students of the experimental group who studied the science material by using the active thinking model on the students of the control group who studied by usual method, in the achievement test. Also the finds show that the students of the experimental group are more successful than students of control group in the test of visual thinking, so the two null hypotheses have been rejected. In light of the results of the research, numbers of recommendations were made.
This paper discusses estimating the two scale parameters of Exponential-Rayleigh distribution for singly type one censored data which is one of the most important Rights censored data, using the maximum likelihood estimation method (MLEM) which is one of the most popular and widely used classic methods, based on an iterative procedure such as the Newton-Raphson to find estimated values for these two scale parameters by using real data for COVID-19 was taken from the Iraqi Ministry of Health and Environment, AL-Karkh General Hospital. The duration of the study was in the interval 4/5/2020 until 31/8/2020 equivalent to 120 days, where the number of patients who entered the (study) hospital with sample size is (n=785). The number o
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