A novel demountable shear connector is proposed to link a concrete slab to steel sections in a way that resulting steel-concrete composite floor is demountable, i.e. it can be easily dismantled at the end of its service life. The proposed connectors consist of two parts: the first part is a hollow steel tube with internal threads at its lower end. The second part is a compatible partially threaded bolted stud. After linking the stud to the steel section, the hollow steel tube can be fastened over the threaded stud, which create a complete demountable shear connector. The connector is suitable for use in both composite bridges and buildings, and using cast in-situ slabs, precast solid slabs, or hollow-core precast slabs. A series of push-off tests with different parameters including wall thickness of steel tube, compressive strength of concrete slab and infilled grout were carried out to study shear strength, shear stiffness, failure modes and relative slip characteristics of demountable shear connectors. Experimental results indicated that the shear connector has a high strength and initial stiffness, also the slip capacity that is higher than the requirements of the current codes of practice. Finally, it is suggested that under applied loading, concrete slabs do not crack or crush, demountable connectors can yield into plastic state, therefore, concrete slabs and steel beams can be easily replaced, repaired or reused.
The article considers semantic and stylistic motivations for using obsolete lexicon (historicisms) in the text of a work of art. The specifics of the functioning of this process are presented against the background of the features of the contemporary Russian literary language. Attention is focused on the fact that the layer of obsolete lexical units belongs to a number of nationally specific vocabulary, the development of which forms an understanding of the nature of the actualized language. In addition, it should be noted that the semantics of historicisms is culturally commensurate: the latter is explained by the fact that the deactuation of linguistic units is positioned as parallel to the sociocultural and political changes.
... Show MoreAntibiotic resistance is a problem of deep scientific concern both in hospital and community settings. Rapid detection in clinical laboratories is essential for the judicious recognition of antimicrobial resistant organisms. So, the growth of Uropathgenic Escherichia coli (UPEC) isolates with Multidrug-resistant (MDR) and Extensively Drug-resistant (XDR) profiles that thwart therapy for (UTIs) has been detected and has straight squeezed costs and extended hospital stays. This study aims to detect MDR- and XDR-UPEC isolates. Out of 42 UPEC clinical isolates were composed from UTI patients. The bacterial strains were recognized by standard laboratory protocols. Susceptibility to antibiotic was measured by the standard disk diffusi
... Show MoreThe research aims to determine the required rate of return according to the Fama and French five-factor model, after strengthening it by adding the indebtedness factor to build the Fama and French six-factor model FF6M-DLE. The effect of the indebtedness factor on the company's profitability and the real value of the ordinary shares calculated according to the (equivalent ascertainment) model and its suitability with the company's situation, and an analysis of the fluctuation between the market value and the real value of the ordinary stocks.
Coronavirus 2019 (COVID-19) pandemic led to a massive global socio-economic tragedy that has impacted the ecosystem. This paper aims to contextualize urban and rural environmental situations during the COVID-19 pandemic in the Middle East and North Africa (MENA) Region.
An online survey was conducted, 6770 participants were included in the final analysis, and 64% were females. The majority of the participants were urban citizens (74%). Over 50% of the urban residents significantly (
This work represents the preparation of the starting material, 3-chloro-2-oxo-1,4-dithiacyclohexane (S) using a new method. This material was reacted with, 4-phenylthiosemicarbazide to give (H3NS3) as a tetradentate ligand H3L. New complex of rhenium (V) with this ligand of the formula [ReO(L)] was prepared. New complexes of the general formula [M(HL)] of this ligand when reacted with some metal ions where: M = Ni(II), Cu(II), Cd(II), Zn(II), Hg(II) have been reported. The ligand and the complexes were characterized by infrared, ultraviolet–visible, mass, 1H nuclear magnetic resonance and atomic absorption spectroscopic techniques and by (HPLC), elemental analysis, and electrical conductivity. The proposed structure for H3L with Re (V) i
... Show MoreSilver nanoparticles synthesized by different species
Compound 4-(((6-amino-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl)methoxy)methyl)- 2,6-dimethoxyphenol (6) was synthesized by multi steps. The corresponding acetonitrile thioalkyl (7) was cyclized by refluxing with acetic acid to afford 4-(((6-amino-7H-[1,2,4]triazolo[3,4- b][1,3,4]thiadiazin-3-yl)methoxy)methyl)-2,6-dimethoxyphenol (8). Two new series of 4-(((6-(3- (4-aryl)thioureido)-7H-[1,2,4]triazolo[3,4-b][1,3,4] thiadiazin-3-yl)methoxy)methyl)-2,6- dimethoxyphenol (9a-c) and of 4-(((6-(substitutedbenzamido)7H-[1,2,4]triazolo[3,4- b][1,3,4]thiadiazin-3-yl)methoxy)methyl)-2,6-dimethoxyphenol (10a-c) were synthesized as new derivatives for fused 1,2,4-trizaole-thiadiazine(8). The antioxidants of newly compounds were evaluated by DPPH
... Show MoreThe present study was investigated the activity of aqueous extract from Cinnamomum cassia bark on the blood glucose levels in healthy and diabetic rats induced by Streptozotcin (STZ). In healthy rats the blood glucose levels were slightly decreased after six hoursof single oral administration with dose (25 mg/kg) of body wight, as well as four weeks after twice daily repeated oral administration of aqueous extract of Cinnamomum cassia bark. In streptozotocin induced diabetic rats we absorved high significant decreased (p<0.05) in blood glucose levels, after four weeks of oral administration of aqueous extract (25 mg /kg ).And blood glucose levels seems to be normal after the period of treatment .Glibenclamide used as standard drug to com
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