Oxidative C-H/C-H Coupling of Dipyrromethanes with Azines by tio2-Based Photocatalytic System. Synthesis of New Bodipy Dyes and Their Photophysical and Electrochemical Properties

Oxidative C-H/C-H coupling reactions of dipyrromethanes with azines in the presence of a heterophase oxidative photocatalytic system (O2/TiO2/visible light irradiation) were carried out. As a result of cyclization of obtained compounds with boron trifluoride etherate, new hetaryl-containing derivatives of 4,4-difluoro-4-boron-3a,4a-diaza-s-indacene were synthesized. For the obtained compounds, absorption and luminescence spectra, quantum yields of luminescence as well as cyclic volt-amperograms were measured. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Funding: This research was supported by the Russian Foundation for Basic Research, research project numbers 20-43-660054 and 19-29-08037. The photophysical studies were carried out within the state assignment no AAAA-A19-119070790003-7

On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection

A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D 2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion 55 093013)

Progress in understanding disruptions triggered by massive gas injection via 3D non-linear MHD modelling with JOREK

3D non-linear MHD simulations of a D 2 massive gas injection (MGI) triggered disruption in JET with the JOREK code provide results which are qualitatively consistent with experimental observations and shed light on the physics at play. In particular, it is observed that the gas destabilizes a large m/n = 2/1 tearing mode, with the island O-point coinciding with the gas deposition region, by enhancing the plasma resistivity via cooling. When the 2/1 island gets so large that its inner side reaches the q = 3/2 surface, a 3/2 tearing mode grows. Simulations suggest that this is due to a steepening of the current profile right inside q = 3/2. Magnetic field stochastization over a large fraction of the minor radius as well as the growth of higher n modes ensue rapidly, leading to the thermal quench (TQ). The role of the 1/1 internal kink mode is discussed. An I p spike at the TQ is obtained in the simulations but with a smaller amplitude than in the experiment. Possible reasons are discussed

Measurement of fractional frequency difference and frequency stability calculation

Praca prezentuje metodę pomiaru odchylenia względnego częstotliwości (o.w.cz.) oraz wyznaczania niestabilności częstotliwości (odchylenie Allana) wzorców częstotliwości za pomocą komparatora fazy i częstotliwości w połączeniu z częstościomierzem cyfrowym. Dane pomiarowe zbierane są automatycznie i przeliczane przy pomocy arkuszy kalkulacyjnych oraz specjalistycznego oprogramowania do analizy danych w dziedzinie częstotliwości Stable 32. W pracy zawarto również analizę źródeł niepewności występujących przy pomiarach częstotliwości oraz opisano sposób wyznaczania poprawki związanej z prognozą o.w.cz. wzorca odniesienia.This paper presents a method of fractional frequency difference measurement and frequency stability (Allan deviation) calculation of frequency standards with frequency and phase comparator in connection with a frequency counter. Measurement data are collected automatically and calculated with calculation sheets or with special purpose software Stable 32 for time- and frequency-domain data analysis. This paper presents also the sources of uncertainties that occur during frequency measurement and reveals the method of reference standard accuracy prognosis calculation

The issue of metrological terminology and the process of its implementation

W ostatnich kilkunastu latach nastąpił znaczący postęp w pracach nad terminologią metrologiczną. Pomimo starań na rzecz wdrożenia jednolitej i poprawnej terminologii wciąż obserwuje się rozbieżności terminologiczne i liczne przykłady wadliwej lub źle interpretowanej terminologii. Koniecznym wydaje się poddać analizie proces wdrażania poprawnej terminologii i możliwość minimalizacji towarzyszących mu negatywnych zjawisk.In the recent years, there has been significant progress made in metrological terminology works. This article describes a work, that has been carried out on implementation of proper and uniform terminology. Despite the release of international publications such as vocabularies (of basic and general terms in metrology and of terms in legal metrology) terminological discrepancies and numerous examples of defective or misinterpreted terminology are continuously observed. Another aspect of terminological confusion are neglectful, incorrect and defective translations of both, legal and technical documents. Negative effects of terminological inconsistence are, most of all, interpretation problems concerning instruments technical parameters, interpretation and application of legal provisions or deepening problem of general understanding of even basic metrological terms. It seems indispensable that in the framework of terminological works attention be paid to the problems of implementation of uniform, internationally agreed upon terminology in metrology. This article gives some encountered examples of defective or inaccurate usage of metrological terms. An attempt was also made to diagnose the situation and to propose some solutions to improve the current state. Looking at the whole work in the field of metrological terminology, it should be noted that it is necessary to effectively implement it, which requires special, targeted actions. They should be the domain of many metrological institutions, not only state bodies. However, situations in which mistakes, misunderstandings or controversies may arise are unavoidable. It is necessary in such situations to rationally seek a solution to the problem and comply with rules that will prevent the negative consequences of a wide range