Resistance spot welding (RSW) aluminum alloys has a major problem of inconsistent quality from weld to weld, because of the problems of the non-uniform oxide layer. The high resistivity of the oxide causes strong heat released which influence significantly on the electrode lifetime and the weld quality. Much effort has been devoted experimentally to the study of the sheet surface characteristics for as-received sheet and surface pretreatment sheet by pickling in NaOH and glassblasted with three thicknesses (0.6, 1.0, and 1.5 mm) of AA1050. Three different welding process parameters energy setup as a low, medium, and high were carried. Tensile-shear strength tests were performed to indicate the weld quality. Moreover, microhardness tests, macro/micrographs, and
SEM/EDS examinations were carried out to analyze, compare, and evaluate the effect of surface conditions on the weldability. The as received sheet showed a higher electrical contact resistance because of its thicker and non-uniform oxide layer. In contrast, the glass-blasted sheet showed lower value, since it has a roughest surface, which leads to easy breakdown the oxide layer. The highest average values and least scattering of the maximum load fracture are with treated sheet by
pickling in NaOH, these values are 760, 1193, and 2283 N for 0.6, 1.0, and 1.5 mm sheet thickness respectively for medium input energy. In contrast, the minimum values with glass-blasted sheet are 616, 1008, and 2020 N for 0.6, 1.0, and 1.5 mm sheet. The microhardness profiles of the fusion zone and HAZ is the lower than the base metal for all cases. Numerical simulation with SORPAS® was used to simulate and optimize the process parameters, and it has given good results in prediction when they compared with experiments.
Efficacy of Varnishes with: Bioactive Glass, Recaldent Technology and Silver Diamine Fluoride in Comparison with Sodium Fluoride on Tooth Surface Micro-hardness (an In Vitro Study)
Die Zusammenfassung :
In der Forschung „ Die Wirkungen der Nachkriegliteratur „ findet man einen Überblick über die Wirkungen der Literatur im Allgemeinen und besonders über die Wirkungen der Nachkriegliteratur in Deutschland. Das Kurzgeschichte „ das Brot“ von Wolfgang Borchert „ wird in dieser Forschung als Beispiel analysiuert, weil sie die Nachteile des Kriegs und ihre Wirkungen auf die Familienbeziehungen behandelt. Die Hauptfiguren der Kurzgeschichte sind ein alter Mann und seine Frau. Der Schriftsteller bestimmt die Rolle der Frauen in Deutschland. Die Frau in dieser Geschichte ist stärker als ihren Mann , denn er war lügner und schwach.
Post-war Literature has an e
... Show MoreLimitations of the conventional diagnostic techniques urged researchers to seek novel methods to predict, diagnose, and monitor periodontal disease. Use of the biomarkers available in oral fluids could be a revolutionary surrogate for the manual probing/diagnostic radiograph. Several salivary biomarkers have the potential to accurately discriminate periodontal health and disease. This study aimed to determine the diagnostic sensitivity and specificity of salivary interleukin (IL)‐17, receptor activator of nuclear factor‐κB ligand (RANKL), osteoprotegerin (OPG), RANKL/OPG for differentiating (1) periodontal health from disease and (2) stable a
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 MoreApplications of quantitative methods, which had been explicit attention during previous period (the last two centuries) is the method of application sales man or traveling salesman method. According to this interest by the actual need for a lot of the production sectors and companies that distribute their products, whether locally made or the imported for customers or other industry sectors where most of the productive sectors and companies distributed always aspired to (increase profits, imports, the production quantity, quantity of exports. etc. ...) this is the part of the other hand, want to behave during the process of distribution routes that achieve the best or the least or most appropriate.
... Show MoreThe compound [L] was produced in the current study through the reaction of 4-aminoacetophenon with 4-methoxyaniline in the cold, concentrated HCl with 10% NaNO2. Curcumin, several transition metal complexes (Ni (II), La (III), and Hg (II)), and compound [L] were combined in EtOH to create new complexes. UV-vis spectroscopy, FTIR, AA, TGA-DSC, conductivity, chloride content, and elemental analysis (CHNS) were used to describe the structure of produced complexes. Biological activities against fungi, S. aureus (G+), Pseudomonas (G-), E. coli (G-), and Proteus (G-) were demonstrated using complexes. Depending on the outcomes of the aforementioned methods, octahedral formulas were given as the geometrical structures for each created comp
... Show MoreFour Co(II), (C1); Ni(II), (C2); Cu(II), (C3) and Zn(II), (C4) chelates have been synthesized with 1-(4-((2-amino- 5‑methoxy)diazenyl)phenyl)ethanone ligand (L). The produced compounds have been identified by using spectral studies, elemental analysis (C.H.N.O), conductivity and magnetic properties. The produced metal chelates were studied using molar ratio as well as sequences contrast types. Rate of concentration (1 ×10 4 - 3 ×10 4 Mol/L) sequence Beer’s law. Compound solutions have been noticed height molar absorptivity. The free of ligand and metal chelates had been applied as disperse dyes on cotton fabrics. Furthermore, the antibacterial activity of the produced compounds against various bacteria had been investigated. F
... Show MoreCoronavirus 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 (