95 research outputs found
Influence of Filler Metals in Welding Wires on the Phase and Chemical Composition of Weld Metal
The influence of filler metals used in welding wires on the phase and chemical composition of the metal, which is surfaced to mining equipment exposed to abrasive wear, has been investigated. Under a laboratory environment, samples of Mo-V-B and Cr-Mn-Mo-V wires were made. The performed experiments have revealed that fillers of the Cr-Mn-Mo-V system used in powder wire show better wear resistance of the weld metal than that of the Mn-Mo-V-B system; the absence of boron, which promotes grain refinement in the Mn-Mo-V-B system, significantly reduces wear resistance; the Mn-Mo-V-B weld metal has a finer structure than the Cr-Mn-Mo-V weld metal
Modification of naturally occurring chromones with azines. Hetarylation using 6-phenyl-1,2,4-triazin-3-one
A simple and efficient method for modifying naturally occurring 5,7-dihydroxychromones using 6-phenyl-1,2,4-triazin-3(2H)-one was developed. The reaction was found to proceed in good yield by refluxing a mixture of the reactants in acetonitrile in the presence of trifluoromethanesulfonic acid as a catalyst to form the product of nucleophilic addition of chromone in position 6 at the 5-position of the triazine ring. The structures of the compounds obtained were proved using 2D NMR spectroscopy and mass spectrometry
Direct Modification of Quercetin by 6-Nitroazolo[1,5-a]Pyrimidines
The work was sponsored by the Russian Science Foundation (Project 14-13-01301)
Performance of the SAET of the Stavropol Anti-Plague Institute of the Rospotrebnadzor during the XXII Olympic and XI Paralympic Winter Games in Sochi
Given is a general overview of the SAET performance during the XXII Olympic and XI Paralympic Winter Games, 2014 in Sochi. Discussed are the peculiarities of work management of the SAET diagnostic facilities; represented are the data on the structure and scope of laboratory investigations of clinical material and environmental samples. Analyzed is the experience of operation under major international mass event. Consequently, it is concluded that current SAET structure, its stuffing and equipping, the laid-up stock of preparations and test-systems have allowed for coping with a diverse task complex in the laboratory diagnostics of infectious diseases and indication of their agents
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