In this paper, numerical and experimental studies on the elastic behavior of glass fiber reinforced polymer (GFRP) with stiffeners in the GFRP section's web (to prevent local buckling) are presented. The GFRP profiles were connected to the concrete deck slab by shear connectors. Two full-scale simply supported composite beams (with and without stiffeners) were tested under impact load (three-point load) to assess its structural response. The results proved that the maximum impact force, maximum deflection, damping time, and damping ratio of the composite beam were affected by the GFRP stiffeners. The experimental results indicated that the damping ratio and deflection were diminished compared to hybrid beam without stiffeners by 16% and 22%, respectively, and increasing damping time by 26%. Finite element models were used to study pre-failure behavior. The numerical modeling results showed good agreement with experimental data in terms of loading path and final load. The damping ratio and midspan deflection values were greater than the experimental values by 6% and 12%, respectively.
In the present research the flame retardancy to buildings and industrial foundations which are manufacturing from advanced polymeric composite material was increased by coating it with surface layer included flame retardant material. A(3mm) thick antimony tetroxide was used as a coated layer to retard and prevent the flame spread to the coating surface of polyester resin (SIROPOL 8340-PI) reinforced with hybrid fibers as a woven roving (°45-°0) consist of carbon and kevlar (49) fibers, and exposed it to direct flame generated from gas torch at temperature of (2000ºC), at different exposed distance (10,15,20mm)and study the rang of resistance for this layer and its ability to protec
... Show MoreCoupling reaction of 4-aminoantipyrene with 8-hydroxyqunoline gave the new bidentate azo ligand 5-(4-antipyrene azo)-8-hydroxyqunoline. Treatment of this ligand with the following metals ions (MnII, CoII, NiII, CuII and ZnII) in aqueous ethanol with a 1:2 M:L ratio yielded a series of neutral complexes of the general formula [M(L)2Cl2]. The prepared complexes were characterized using flame atomic absorption, FT.IR, UV-Vis spectroscopic as well as magnetic susceptibility and conductivity measurements. Chloride ion content were also evaluated by (Mohr Method). From above data, the proposed molecular structure for these complexes as octahedral geometry.
Rock type identification is very important task in Reservoir characterization in order to constrict robust reservoir models. There are several approaches have been introduced to define the rock type in reservoirs and each approach should relate the geological and petrophysical properties, such that each rock type is proportional to a unique hydraulic flow unit. A hydraulic flow unit is a reservoir zone that is laterally and vertically has similar flow and bedding characteristics. According to effect of rock type in reservoir performance, many empirical and statistical approaches introduced. In this paper Cluster Analysis technique is used to identify the rock groups in tertiary reservoir for Khabaz oil field by analyses variation o
... Show MoreThe current study performed in order to detect and quantify epicatechin in two tea samples of Camellia sinensis (black and green tea) by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Extraction of epicatechin from black and green tea was done by using two different methods: maceration (cold extraction method) and decoction (hot extraction method). Qualitative and quantitative determinations of epicatechin in two tea samples were investigated. Epicatechin identification was made by utilizing preliminary chemical tests and TLC. This identification was also boosted by HPLC and then quantified epicatechin in all ethyl acetate fractions of two tea samples. This research revealed the existence of epica
... Show MoreThis work is an experimental investigation for single basin-single slope solar still coupled with an evacuated tube solar collector. The work is carried out under the climatic conditions of Baghdad city (33.2456º North and East latitude, 44.3337º longitude) through certain days of the months of the year 2019 to study the impact of using evacuated tube solar collector on the daily productivity and efficiency under the outdoors climatic conditions. It was found that using the evacuated tube solar collector increase daily productivity from 2.175 kg/ to 2.95 kg/ for 9 hours (35.63 %) for clear days, also an enhancement about 10.97 % in daily efficiency.
Biological activity substances was investigated in watery extract of lentil which found to contain phenols, tannin, saponins and resins while, flavons, terpens and steroids were not exist in the extract details explained that 5%, 10% of lentil extract largly inhibited the growth of Psedumonas aeruginosa then Escherichia coli and Bacillus subtilis. The growth of both Staphylococcus aureus and Salmonella typhimurium were slightly affected by all extract concentration. Extracellular protease were screened in all bacterial species under study. Complete inhibition was achieved for extracellular protease while different percentage of protease inhibition were seen for intracellular proteases.
A solid Phase Extraction (SPE) followed by HPLC-UV method is described for the simultaneous quantitative determination of nine priority pollutant phenols : Phenol, 2- and 4-Nitrophenol, 2,4-Dimethylphenol, 2-, 2,4-Di-, 2,4,6-Tri-, and Penta- chlorophenol, 4 Chloro-3-methylphenol. The phenols were separated using a C-18 column with UV detector at wave length of 280nm. The Flow of mobile phase was isocratic consisted of 50:50 Acetonitrile: phosphate buffer pH=7.1, column temperature 45 C°, Flow Rate 0.7 ml/min. Calibration curves were linear (R2 = 0.9961-0.9995). The RSDs (1.301-5.805)%, LOD(39.1- 412.4) µg/L, LOQ(118.5-1250.8) µg/L, the Robustness (1.55-4.89), Ruggedness (2.82-4.00), Repeatability (2.1-4.95), Recoveries%
... Show MoreThere are many diseases that affect the arteries, especially those related to their elasticity and stiffness, and they can be guessed by estimating and calculating the modulus of elasticity. Hence, the accurate calculation of the elastic modulus leads to an accurate assessment of these diseases, especially in their early stages, which can contribute to the treatment of these diseases early. Most of the calculations used the one-dimensional (1D) modulus of elasticity. From a mechanical point of view, the stresses to which the artery is subjected are not one-dimensional, but three-dimensional. Therefore, estimating at least a two-dimensional (2D) modulus of elasticity will necessarily be more accurate. To the knowledge of researchers, there i
... Show MoreBackground: Esthetic correction represents one of the clinical conditions that required the use of laminate veneers in premolars region. Aim of the study: The purpose of this study was to evaluate the fracture strength of the laminate veneers in maxillary first premolars, fabricated from either composite (direct and indirect techniques) or ceramic CAD/CAM blocks. Materials and Methods: Fifty sound human maxillary premolar teeth were used in this in vitro study. Teeth were divided randomly into one control group and four experimental groups of ten teeth each; Group A: Restored with direct composite veneer (Filtek Z250 XT), Group B: Restored with indirect composite veneers (Filtek Z250 XT), Group C: Restored with lithium disilicate ceramic CA
... Show MoreGingivitis, the initial stage of periodontal disease, is characterised by inflammation driven by dental biofilm and associated with oxidative stress. Matcha tea, a powdered green tea rich in antioxidants, has shown potential health benefits. This study aimed to investigate the effect of Matcha tea consumption on clinical periodontal parameters and salivary antioxidant levels in patients with gingivitis.
A randomised controlled clinical trial was conducted with 41 participants diagnosed with gingivitis.