Surface morphology, magnetic resonant and antistatic properties of 07S11-KVfabric coated with stainless steel

A study of the mixed 07С11-KВ fabric (produced by Mogotex) with a coating of steel 12X18H10T, obtained by the method of pulsed cathode arc deposition in a vacuum of 3.5×10–3 Pa, was conducted. It is shown that optical microscopy has a number of advantages in studying the surface morphology of such objects as compared to scanning electron microscopy. The most contrast image is formed using dark-field illumination. When coating is applied, a droplet phase is formed, the droplet sizes vary from 2 to 10 microns. By the method of electron paramagnetic resonance, it has been established that the spectrum of coated fabric has an asymmetrical spectral line with a width of 101 mT, which indicates a high concentration of magnetic resonance centers and a significant resonant absorption of microwave energy. Resonant absorption at low magnetic fields is determined by clusters of iron, nickel, chromium, titanium, etc., with weak nonresonant absorption. The specific surface resistance of the fabric (side 1 / side 2) is 3.3×105 ohm and 5.6×105 ohm, respectively

Catalytic Adaptive Recognition of Thiol (SH) and Selenol (SeH) Groups Toward Synthesis of Functionalized Vinyl Monomers

An unprecedented sustainable procedure was developed to produce functionalized vinyl monomers H₂CC­(R)­(FG) starting from a mixture of sulfur and selenium compounds as a functional group donor (FG = S or Se). The reaction serves as a model for efficient utilization of natural resources of sulfur feedstock in oil and technological sources of sulfur/selenium. The catalytic system is reported with amazing ability to recognize SH/SeH groups in the mixture and selectively incorporate them into valuable organic products via wastes-free atom-economic reaction with alkynes (HCCR). Formation of catalyst active site and the mechanism of the catalytic reaction were revealed by joint experimental and theoretical study. The difference in reactivity of μ₁- and μ₂-type chalcogen atoms attached to the metal was established and was shown to play the key role in the action of palladium catalyst. An approach to solve a challenging problem of dynamically changed reaction mixture was demonstrated using adaptive tuning of the catalyst. The origins of the adaptive tuning effect were investigated at molecular level and were found to be governed by the nature of metal–chalcogen bond

A chemically powered unidirectional rotary molecular motor based on a palladium redox cycle

The conversion of chemical energy to drive directional motion at the molecular level allows biological systems, ranging from subcellular components to whole organisms, to perform a myriad of dynamic functions and respond to changes in the environment. Directional movement has been demonstrated in artificial molecular systems, but the fundamental motif of unidirectional rotary motion along a single-bond rotary axle induced by metal-catalysed transformation of chemical fuels has not been realized, and the challenge is to couple the metal-centred redox processes to stepwise changes in conformation to arrive at a full unidirectional rotary cycle. Here, we present the design of an organopalladium-based motor and the experimental demonstration of a 360° unidirectional rotary cycle using simple chemical fuels. Exploiting fundamental reactivity principles in organometallic chemistry enables control of directional rotation and offers the potential of harnessing the wealth of opportunities offered by transition-metal-based catalytic conversions to drive motion and dynamic functions

Suzuki-Miyaura Cross-Coupling of Unprotected, Nitrogen-Rich Heterocycles: Substrate Scope and Mechanistic Investigation

The Suzuki-Miyaura cross-coupling of unprotected, nitrogen-rich heterocycles using precatalysts P1 or P2 is reported. The procedure allows for the reaction of variously substituted indazole, benzimidazole, pyrazole, indole, oxindole, and azaindole halides under mild conditions in good to excellent yields. Additionally, the mechanism behind the inhibitory effect of unprotected azoles on Pd-catalyzed cross-coupling reactions is described based on evidence gained through experimental, crystallographic, and theoretical investigations.National Institutes of Health (U.S.) (Award GM46059)German Science Foundation (Postdoctoral Fellowship

Microfluidics in Biotechnology: Quo Vadis

Winkler S, Grünberger A, Bahnemann J. Microfluidics in Biotechnology: Quo Vadis. Advances in biochemical engineering/biotechnology. 2021:1-26.The emerging technique of microfluidics offers new approaches for precisely controlling fluidic conditions on a small scale, while simultaneously facilitating data collection in both high-throughput and quantitative manners. As such, the so-called lab-on-a-chip (LOC) systems have the potential to revolutionize the field of biotechnology. But what needs to happen in order to truly integrate them into routine biotechnological applications? In this chapter, some of the most promising applications of microfluidic technology within the field of biotechnology are surveyed, and a few strategies for overcoming current challenges posed by microfluidic LOC systems are examined. In addition, we also discuss the intensifying trend (across all biotechnology fields) of using point-of-use applications which is being facilitated by new technological achievements