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The paper presents the results of measuring the surface adhesion fi gures of a dielectric (non-foiled glass-cloth-base laminate) and a conductor (foiled glass-cloth-base laminate) obtained by the adhesive tape tear-off method, as well as the surface potential depending on the time of storage of samples in natural conditions after activation of their surface by plasma-chemical etching. The obtained dependences are complex declining functions of time.

Membranes on the basis of synthetic and modifi ed natural polymeric substrates are widely used in separation and fi ltration processes and as conductive or isolating media. Grafting acrylic monomers onto polymeric substrates is an eff ective method of their production. Polyethylene, a synthetic polymer, has high strength properties, thermal and chemical resistance, which makes it a good substrate for various products.

The calculation of the specifi c electrical conductivity of lithium and sodium fl uorides mixtures melts is presented. The Iinterest in the LiF–NaF system melts is determined by their practical signifi cance. Melts of LiF+NaF mixtures are used in heat-storing compositions and in metallurgy. They are part of various multicomponent systems.

This work summarizes one-pot synthetic approaches to spiro-fused (di)azoles, which are promising in terms of studying biological activity. Proposed approaches involve condensation reactions of (hetero)cyclic ketones, methylene active moieties, and N-nucleophiles, occurring under mild conditions by both stepwise and concerted mechanisms. The antimicrobial activity of signals from the proposed approaches of cyanosubstituted spiro-membered pyrazolines and pyrrolidines against gram-negative (P. aeruginosa, E. coli) and gram-positive (S.

Doxycycline is a broad-spectrum tetracycline antibiotic used to treat infections in humans and in veterinary medicine as a prophylactic drug and growth stimulant. For this reason, residual amounts of antibiotics in milk, meat and other food products can cause resistance and the development of allergies. In this regard, constant monitoring of residual contents of tetracyclines in food products, environmental objects, and biological fl uids is required.

Graft copolymerization onto a solid polymer surface is an eff ective tool for its modifi cation. A large number of works have been published and require systematization. A search and review of English-language scientifi c literature devoted to the graft copolymerization of acrylic monomers onto a polymeric solid-phase surface have been carried out. Grafting onto plates and fi lms, as well as fi bers and colloidal particles, is considered.

The use of mid-fi eld infrared spectroscopy in combination with chemometric algorithms for the identifi cation of cephalosporin antibiotics in the form of injectable powders is demonstrated. III generation cephalosporins have been selected as objects of the study: ceftriaxone, ceftazidime, cefotaxime, which are widely used in pharmaceutical practice. IR spectra of the medical preparations have been recorded using an FT-801 Fourier transform IR spectrometer with an attenuated total refl ection (ATR) attachment.