Fluorescent amino acids as versatile building blocks for chemical biology

Fluorophores have transformed the way we study biological systems, enabling non-invasive studies in cells and intact organisms, which increase our understanding of complex processes at the molecular level. Fluorescent amino acids have become an essential chemical tool because they can be used to construct fluorescent macromolecules, such as peptides and proteins, without disrupting their native biomolecular properties. Fluorescent and fluorogenic amino acids with unique photophysical properties have been designed for tracking protein–protein interactions in situ or imaging nanoscopic events in real time with high spatial resolution. In this Review, we discuss advances in the design and synthesis of fluorescent amino acids and how they have contributed to the field of chemical biology in the past 10 years. Important areas of research that we review include novel methodologies to synthesize building blocks with tunable spectral properties, their integration into peptide and protein scaffolds using site-specific genetic encoding and bioorthogonal approaches, and their application to design novel artificial proteins, as well as to investigate biological processes in cells by means of optical imaging. [Figure not available: see fulltext.]

Water evaporation particularities in the process of forest fire extinguishing

Numerical simulation of water massif motion through the high temperature gases corresponding to the typical conditions of forest fires was carried out. Maximal values of part by volume of liquid evaporating from water massif under its motion through the flaming burning area were determined when solving the heat and mass transfer problem under the conditions of endothermic phase transformations. Influence of liquid phase transition heat on the heat and mass transfer conditions on the track of water massif was determined. The expediency of polydisperse interspaced in time and space atomization of water massifs under the large-scale (especially, forest fires) fire extinguishing was proved

Studies of the Adsorption of Organic Vapours by Metal Stearates and Their Complexes with Octadecylamine in a Flow Impulse Regime by Piezoquartz Sensor Techniques

The adsorption properties of metal (Co 2+ , Ni 2+ and Cu 2+ ) stearates and their coordination compounds with octadecylamine, as well as those of carbon nanotubes (CNTs), have been studied by piezoquartz resonator (PQR) sensor techniques in steady flow and flow impulse regimes for vapours of volatile organic compounds (VOCs), especially hydrocarbons. It was shown that the adsorption of hydrocarbon homologues onto each of the studied sensor coverings was characterized by a linear dependence between the logarithm of the Henry constant and the boiling points of the corresponding substances. Such individual linear dependencies were observed for a series of alkanes, cyclanes and aromatics. The slopes of these dependencies differed for different sensor coverings. This allowed discrimination between individual hydrocarbon analogues by using these coverings in a PQR sensor array in combination with the proposed flow impulse technique

Forecasting investigation of mode fire hazard of electrical overload of cable lines

The physical and predictive mathematical models of heat and mass transfer, phase transformations and chemical reaction have been developed to determine the necessary and sufficient conditions of inflammation and fire nascence at typical cable lines electrical overloads. The integral characteristics of study process complex – ignition delay times have been established according to cable lines electrical overloads modes. The temperature distributions in typical cable lines at overloads have been determined. The concentration variation characteristic ranges (which are sufficient for gas-phase ignition) of thermal decomposition components of cable sheaths at overloads have been adduced. The two-dimensional heat-and-mass transfer problem for a three-layer cable in the area of limited heat sink is solved. Thermal decomposition of the cable sheath and diffusion of thermal decomposition components and air were taken into account. Fire risk assessment of cable lines on overload in conditions of limited heat transfer is carried out. The dependence of ignition time delay for mixture of oxidized and thermal decomposition components from intensity of a current