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The possibility of increasing the corrosion resistance of titanium by electroplating molybdenum carbide coatings from the melts was studied.Molybdenum and molybdenum carbide are widely used as components of corrosion-resistant steels and alloys and of coatings for surface modification. Therefore, the corrosion and electrochemical behavior of molybdenum and molybdenum carbide in aggressive media attracts growing researchers' attention. Various methods are used for surface modification of titanium. For example, the deposition of platinum-group metals increases the corrosion resistance of titanium in hot solutions of acids by several orders of magnitude [1,2]. However, noble metals are expensive, which makes application of this protection method limited. Alloying titanium with molybdenum shows promise [1,3,4]. At the same time, the level of alloying ensuring high corrosion resistance should be no less than 20 325%. This level is successfully attained when, for example, the method of diffusion saturation from solid mixtures with the oxide activator in a vacuum or under argon at 1100 31200oC is used for surface alloying of titanium samples with molybdenum [5]. The method of the high-temperature electrochemical synthesis (HTES) from ionic melts allows the temperature of alloying of titanium with molybdenum, tungsten, and their carbides to be decreased to 800 3900oC and alloying time to be shortened considerably. In this case, the corrosion resistance of St.3 and St.45 steels in sodium chloride solutions and in hot concentrated and dilute solutions of hydrochloric, sulfuric, and phosphoric acids considerably increases.In this study we examined the electrochemical and corrosion behavior of titanium, onto which molybdenum carbide coating was deposited by HTES, in a sulfuric acid solution. Because Mo 2 C is in short supply and is brittle at room temperature, it has not found wide application in industry as structural material [1,8]. At the same time, it is an important alloying component for coating deposition.Molybdenum carbide was plated onto VT 13 0 titanium by the HTES method from the melts of composition (mol %): 85 Na 2 WO 4 , 5 MoO 3 , and 10 Li 2 CO 3 at 800 3900oC and a cathodic current density of 0.04 3 0.12 A cm 32 in air. The maximum thickness of the coatings was 50 mm.An important condition for the successful coating deposition is that the corrosion potential of titanium should be more positive than that of carbide (31.60 to 31.90 V vs. the reference electrode (O 2 )Pt 9 Na 2 WO 4 3 0.2 WO 3 in the alloy studied). Therefore, we measured the stationary potentials of titanium in a Na 2 WO 4 3 5 mol % MoO 3 melt containing different amounts of Li 2 CO 3 and estimated whether molybdenum carbide coatings with good adhesion to the substrate can be deposited. The stationary potentials were not established for a long time and varied jumpwise. Apparently, this is associated with dissolution of oxygencontaining phases in the surface layer of the electrode. After measuring the potentials, we studied the composition of su...

It has long been known that materials containing cellulose fibers in their composition are destroyed by molds, microorganisms, actinomycetes, which use cellulose as a carbon source. Different fibrous materials to varying degrees (but always) are affected by molds. It is known that linseed and cotton types of paper are affected by the smallest number of fungi, and sulphate ones by the largest. The most biostable is cotton paper, the composition of which contains chalk in a sufficiently large amount. The observations carried out by the authors showed that the highest biostability (fungal resistance) is characteristic of papers containing chalk and kaolin, the lowest is glued types of paper with a high degree of sizing. Aging of paper with increasing temperature increases the overall susceptibility of all types of paper tested without exception. Obviously, changes in the physical and chemical properties of paper as a result of aging create more favorable conditions for the growth of fungi. It is well known that paper can serve as a medium for the spread of infectious diseases. The authors of the article studied the thermo-physical properties of basalt fiber and investigated the possibility of using it for the manufacture of heat-insulating technical paper.Obtaining materials that are not affected by bacteria, insects and molds (fungicidal,insecticidal) can be solved by using inorganic fibers, which are obtained from almost unlimited natural resources and which have excellent biochemical properties. It should be noted that the concept of "biocidal" paper (material) is collective. It combines species that differ in their ability to kill bacteria (bactericidal), molds (fungicidal), insects (insecticidal). Each of the biocidal types of materials has two or more of these properties.

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One of the main problems today is the storage of funds, provision of storage conditions, the absence of mold, microbiological dispersions in the air, processing of documents, detoxification of previously processed materials. In this work, samples of papers (condenser, writing, carton for lamination) and usage of biocidal materials (Polydez, Gembar and Metatin) were investigated. The technology of processing samples is not very simple. Biocidal effects were carried out on test cultures of microscopic fungi taken from damaged documents. In addition, samples of papers processed with composite mixtures containing basalt and cellulose fibers, montmorillonite clay and sodium resin salts (SSRA) or sodium humate (SH) were studied in parallel. Aging of samples was monitored by indicators such as the material's whiteness and breakthrough strength (n.d.f.)-the properties that are sensitive to the aging process. It has been proved that samples containing basalt and cellulose fibers, montmorillonite and sodium salts of resin acids (or sodium humate) are more likely to suppress the spread of fungi and microorganisms than official state biocidal materials. Therefore, in this work it is proposed the material and composition mixture, which guarantees certain physical and mechanical properties of the finished product and has a much simpler and cheaper technology to obtain the disinfecting material.