INVESTIGATION OF THE INTERACTION OF UDP METALS WITH PRODUCTS OF THERMAL DECOMPOSITION OF TETRAZOLE BINDER

В статье приводятся экспериментальные исследования ультрадисперсных металлических порошков алюминия, меди, железа, вольфрама, титана, цинка, никеля, сплавов меди с алюминием, меди с железом и латуни. Описаны термические свойства их смесей с метилполивинилтетразолом, пластифицированным динитратпропиленгликолем; указаны численные величины значимых характеристик.Результаты исследования показали, что существенное количество тепла выделяется при нагреве порошков алюминия, цинка, титана и железа; при нагреве смесей со связующим, наилучшие результаты соответствуют сплаву меди с железом, алюминию и сплаву меди с алюминием. The article presents experimental studies of ultrafine metal powders of aluminum, copper, iron, tungsten, titanium, zinc, nickel, alloys of copper with aluminum, copper with iron and brass. The thermal properties of their mixtures with methyl polyvinyl tetrazole and plasticized propylenglycoldinitrate are described; numerical values of significant characteristics are indicated.The results of the study showed that a significant amount of heat is released when heating aluminum, zinc, titanium and iron powders; when heating mixtures with a binder, the best results correspond to an alloy of copper with iron, aluminum and an alloy of copper with aluminum.

Metallic Nanoscaffolds as Osteogenic Promoters: Advances, Challenges and Scope

Bone injuries and fractures are often associated with post-surgical failures, extended healing times, infection, a lack of return to a normal active lifestyle, and corrosion associated allergies. In this regard, this review presents a comprehensive report on advances in nanotechnology driven solutions for bone tissue engineering. The fabrication of metals such as copper, gold, platinum, palladium, silver, strontium, titanium, zinc oxide, and magnetic nanoparticles with tunable physico-chemical and opto-electronic properties for osteogenic scaffolds is discussed here in detail. Furthermore, the rational selection of a polymeric base such as chitosan, collagen, poly (L-lactide), hydroxyl-propyl-methyl cellulose, poly-lactic-co-glycolic acid, polyglucose-sorbitol-carboxymethy ether, polycaprolactone, natural rubber latex, and silk fibroin for scaffold preparation is also discussed. These advanced materials and fabrication strategies not only provide for appropriate mechanical strength but also render integrity, making them appealing for orthopedic applications. Further, such scaffolds can be functionalized with ligands or biomolecules such as hydroxyapatite, polypyrrole (PPy), magnesium, zinc dopants, and growth factors to stimulate osteogenic differentiation, mineralization, and neovascularization to aid in rapid healing. Future directions to co-incorporate bioceramics, biogenic nanoparticles, and fourth generation biomaterials to enhance biocompatibility, mechanical properties, and rapid recovery are also included in this review. Hence, the further development of such biomimetic metal-based nano-scaffolds at a lower cost with reduced risks and greater efficacy at regrowing bone can revolutionize the future of orthopedics.

Tribological Properties of Stainless Steel and Other Corrosion-Resisting Metals

This chapter covers the tribological properties of stainless steel and other corrosion-resistant alloys. It describes the metallurgy and microstructure of the basic types of stainless steel and their suitability for friction and wear applications and in environments where they are subjected to liquid, droplet, and solid particle erosion. It also discusses the tribology of nickel- and cobalt-base alloys as well as titanium, zinc, tin, aluminum, magnesium, beryllium, graphite, and different types of wood.

Titanium, Zinc, Lead, Chromium, Cadmium, Cobalt and Copper Concentrations in Vegetables Produced using Wastewater in Urban and Peri-Urban Areas of Nairobi City County, Kenya

Vegetables are rich sources of vitamins, minerals and fibres. Ingestion of vegetables contaminated with heavy metals is one of the main routes through which heavy metals enter the human body and may cause diseases. In this study we investigated the concentrations of titanium, zinc, lead, chromium, cadmium, cobalt and copper in the commonly produced vegetables viz. Brassica sp.,Spinacia oleracea, Amaranthus sp. and Solanum sp. using wastewater in Ruai ward, Nairobi City County, Kenya. Atomic absorption spectrometry (AAS) was used to estimate the levels of these metals in vegetables sampled from five plots in the study area. The concentration status for each heavy metal in the samples was compared with the permissible levels for corresponding heavy metals set by the Food and Agriculture Organization and World Health Organization. Our findings indicated the presence of Ti, Zn, Cr and Cu in all the vegetable samples and their concentrations varied considerably, while Pb, Cd and Co were not detected in most samples. The presence of heavy metals in vegetables was in the order of Pb > Cd > Co > Cu > Cr > Zn > Ti. We concluded that vegetables produced using wastewater had elevated levels of the investigated heavy metals at the time of analysis beyond FAO/ WHO safe limits for corresponding metals in leafy vegetables.

Nanometals-Containing Polymeric Membranes for Purification Processes

A recent trend in the field of membrane research is the incorporation of nanoparticles into polymeric membranes, which could produce synergistic effects when using different types of materials. This paper discusses the effect of the introduction of different nanometals such as silver, iron, silica, aluminum, titanium, zinc, and copper and their oxides on the permeability, selectivity, hydrophilicity, conductivity, mechanical strength, thermal stability, and antiviral and antibacterial properties of polymeric membranes. The effects of nanoparticle physicochemical properties, type, size, and concentration on a membrane’s intrinsic properties such as pore morphology, porosity, pore size, hydrophilicity/hydrophobicity, membrane surface charge, and roughness are discussed, and the performance of nanocomposite membranes in terms of flux permeation, contaminant rejection, and antifouling capability are reviewed. The wide range of nanocomposite membrane applications including desalination and removal of various contaminants in water-treatment processes are discussed.

Mineralogy and microstructure of skull varieties in blast furnace № 6 JSC EVRAZ NTMK

The results of a comprehensive study of the material composition and microstructure of 20 skull samples taken after blowing out blast furnace № 6 of EVRAZ NTMK JSC are presented. More than 30 minerals and metal phases of different chemical classes were diagnosed in the samples of the skull. Unlike the skull of blast furnaces of other metallurgical plants (NLMK, ZSMK), the skull of NTMK blast furnaces has an abnormally high content of titanium, zinc, vanadium compounds, as well as heavy non-ferrous metals and sulfur. On the basis of a detailed petrographic analysis, 5 structural and genetic types (varieties in composition and origin) of the garnice were identified. The varieties of the garnish contain a large amount of grenal, which is dominated by refractory compounds of titanium and vanadium carbonitrides of the general formula (Ti, V) (C, N).