On the goals of functional diagnostics in general and in relation to gastric cells in particular

If you take the point of view held by my unforgettable teacher, prof. Tarkhanov, that life is the explosive decomposition of the protoplasm of the organism in response to stimuli, and its decomposition is a kind of definite and suitable reflex to a corresponding and suitable stimulus, then it must be admitted that the stimulus must be specific, for it is not always a response to stimulation that a reaction is obtained.

Vibrational Analysis of Benziodoxoles and Benziodazolotetrazoles

Tetrazoles are well known for their high positive enthalpy of formation which makes them attractive as propellants, explosives, and energetic materials. As a step towards a deeper understanding of the stability of benziodazolotetrazole (BIAT)-based materials compared to their benziodoxole (BIO) counterparts, we investigated in this work electronic structure features and bonding properties of two monovalent iodine precursors: 2-iodobenzoic acid and 5-(2-iodophenyl)tetrazole and eight hypervalent iodine (III) compounds: I-hydroxybenzidoxolone, I-methoxybenziodoxolone, I-ethoxybenziodoxolone, I-iso-propoxybenziodoxolone and the corresponding I-hydroxyben ziodazolotetrazole, I-methoxybenziodazolotetrazole, I-ethoxybenziodazolotetrazole and I-iso- propoxybenziodazolotetrazole. As an efficient tool for the interpretation of the experimental IR spectra and for the quantitative assessment of the I−C, I−N, and I−O bond strengths in these compounds reflecting substituent effects, we used the local vibrational mode analysis, originally introduced by Konkoli and Cremer, complemented by electron density and natural bond orbital analyses. Based on the hypothesis that stronger bonds correlate with increased stability, we predict that, for both series, i.e., substituted benziodoxoles and benziodazolotetrazoles, the stability increases as follows: I-iso-propoxy < I-ethoxy < I-methoxy < I-hydroxy. In particular, the I−N bonds in the benziodazolotetrazoles could be identified as the so-called trigger bonds being responsible for the initiation of explosive decomposition in benziodazolotetrazoles. The new insight gained by this work will allow for the design of new benziodazolotetrazole materials with controlled performance or stability based on the modulation of the iodine bonds with its three ligands. The local mode analysis can serve as an effective tool to monitor the bond strengths, in particular to identify potential trigger bonds. We hope that this article will foster future collaboration between the experimental and computational community being engaged in vibrational spectroscopy.

Asphaltene oxide promotes a broad range of synthetic transformations

Carbocatalysts, which are catalytically-active materials derived from carbon-rich sources, are attractive alternatives to metal-based analogs. Graphene oxide is a prototypical example and has been successfully employed in a broad range of synthetic transformations. However, its use is accompanied by a number of practical and fundamental drawbacks. For example, graphene oxide undergoes explosive decomposition when subjected to elevated temperatures or microwaves. We found that asphaltene oxide, an oxidized collection of polycyclic aromatic hydrocarbons that are often discarded from petroleum refining processes, effectively overcomes the drawbacks of using graphene oxide in synthetic chemistry and constitutes a new class of carbocatalysts. Here we show that asphaltene oxide may be used to promote a broad range of transformations, including Claisen-Schmidt condensations, C–C cross-couplings, and Fischer indole syntheses, as well as chemical reactions which benefit from the use of microwave reactors.

Влияние изменения газодинамической разгрузки на лазерное инициирование композита ТЭН-алюминий

Thresholds of explosive decomposition H _cr under irradiation using the first harmonic of a pulsed neodymium laser (14 ns) are experimentally determined for pentaerythritol tetranitrate (PETN) with aluminum nanoparticles (100 nm) at concentrations ranging from 0.05 to 1 wt %. Amplitudes of optoacoustic signals are measured versus concentrations of impurities in the sample at a fixed laser fluence. The experiments are performed in two regimes. In the first one, the irradiated surface of the sample is covered with a finite-weight glass plate that impedes the gas-dynamic unloading. In the second regime, an external pressure of no less than 10^7 Pa is applied to the glass plate to prevent the gas-dynamic unloading. The interpretation of the experimental effects is proven by the results of theoretical simulation.