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In the modern world, special attention is paid to materials with controlled characteristics. In this aspect, polymers and materials based on them have a number of specific properties for effective use in medicine and cosmetology. Humic substances satisfy most of these features, so their use is very important. The study of the features of the processes of gelation in polymer systems such as agar-agar, which has rather universal properties, makes it possible to use it as a basis for gels and polymer carriers, as well as in the processes of obtaining medical and cosmetic materials with different properties, which can be important in solving a number of topical issues. In particular, these are lightweight and cheap to manufacture antiseptic gels, dressings on wounds with absorption and protective properties, all kinds of cosmetics. In the article, a study was carried out to study the processes of gelation and the features of the rheological properties of hydrogels based on agar-agar in order to obtain modern hydrogels with an antibacterial effect. It was found that the introduction of humic acids into the composition of polymer hydrogels slows down the processes of structure formation, which leads to a decrease in the viscosity of all the studied compositions. Also, a decrease in the melting temperature of hydrogel jellies with an increase in the content of humic acids in them indicates a reduced level of gelation, which also leads to an increase in the time of loss of stickiness of polymer hydrogels. It has been shown that humic acids in polymer hydrogels have high antibacterial activity and almost completely stop the processes of mold formation in them. It was found that the most effective from the point of view of obtaining hydrogels with an antibacterial effect are agar-agar compositions with a humic acid content of 15 %. Thus, cosmetic polymer hydrogels with an antibacterial effect have been developed, which can be used in the treatment of hands, face and other areas of the skin that are open and contact for humans to combat coronavirus bacteria.

At the end of 2019, an outbreak of a new coronavirus infection occurred in the People's Re-public of China with an epicenter in the city of Wuhan (Hubei province). On February 11, 2020, the World Health Organization has assigned the official name of the infection caused by the new coronavirus - COVID-19 ("Coronavirus disease2019"). On February 11, 2020, the International Committee on Virus Taxonomy gave the official name to the infectious agent - SARS-CoV-2.Since the end of January 2020, cases of COVID-19 have begun to be registered in many coun-tries of the world, mainly associated with travel to the PRC. At the end of February 2020, the epidemiological situation with COVID-19 in South Korea, Iran and Italy sharply worsened, which subsequently led to a significant increase in the number of cases in other countries of the world associated with travel to these countries, incl. and in Russia. The World Health Organiza-tion announced the COVID-19 pandemic on 11 March 2020, and the pandemic's challenge to the world will remain so as long as people are not immune to it.The Regional Director of the World Health Organization Takeshi Kasai, on the basis of an epidemiological analysis, reports that the spread of coronavirus infection COVID-19 in July-August 2020 occurred mainly among people under 50 years old, and they often did not even know about it, because they had mild or no symptoms. In the future, these people then infect older people who are more difficult to tolerate COVID-19. And we need to redouble our efforts to prevent the spread of the virus in vulnerable communities.

Unified forms of knowledge representation models in expert control systems are proposed. It is proved that at quantitative measurement of the characteristics of the state of the controlled object, the problem of deriving a managerial solution is reduced to the investigation of a combinatorial optimization problem with a linear structure and two-sided inequality constraints. An algorithm for solving such problems is given, which implements the idea of directional selection of variants.

The article deals with the problem of structural organization of liberal arts fragments in the diachronic world view. It considers the application of a prototypical approach to the knowledge categorization about the types and directions of culture and to the differentiation of the tools of their verbal representation in the metalanguage. The classification of the concepts “Renaissance” and “Baroque” under the criteria of modern linguo-cognitive science is proposed. The article provides definitions of prototypical and peripheral units of the categories analyzed and substantiates the differences in their significates. Special attention is paid to non-central category members, as well as to parameters that confirm their categorical status and place them in the general subsystems’ hierarchy. The study substantiates the polysemy of the terms “Renaissance” and “Baroque”, which is caused by the heterogeneity of the classes they represent. Based on the material of specific category units, it demonstrates the possibility of changing their positions as class members and analyzes the causes and consequences of their re-categorization. The article considers the problem of variability and openness of the range of the categories under study, as well as the criteria of their autonomy and integrity. It is shown that the category stability depends on the prototype identification degree and its differences from the central units in other classes. The main conclusions were obtained by analyzing the meanings of the investigated terms and identifying patterns of their attribution to the texts of the corresponding cultural stages. The study novelty lies in the application of cognitive analysis methods to the concepts and term units of the Humanities metalanguage. The research relevance is accounted for by the need to further study the semantics and functioning of interdisciplinary special units in poetics, literary history, art history, cultural studies, and aesthetics. It helps to distinguish the meanings and contexts of using names that are synonymous and antonymous.

У статті розглядаються питання управління температурою перегрітої пари в котельних агрегатах. Температура повинна підтримуватися близькою до своєї величини, заданої при проектуванні агрегату, незалежно від характеру режиму роботи і навантаження котла. Пропонується математичну модель системи регулювання температури перегрітої пари з урахуванням наявних на реальному об’єкті нелінійностей. Встановлено, що система управління адекватно реагує на обурення і відновлює задану температуру перегрітої пари, змінюючи при цьому необхідні параметри системи. Пропонується здійснити модернізацію системи регулювання температурного режиму котельного агрегату за допомогою установки нового пароохолоджувача VariCool і системи діагностики вібрації регулюючих клапанів

The maximum entropy formalism and dimensional analysis are used to derive a power-law spectrum of accelerated electrons in impulsive solar flares, where the particles can contain a significant fraction of the total flare energy. Entropy considerations are used to derive a power-law spectrum for a particle distribution characterised by its order of magnitude of energy. The derivation extends an earlier one-dimensional argument to the case of an isotropic three-dimensional particle distribution. Dimensional arguments employ the idea that the spectrum should reflect a balance between the processes of energy input into the corona and energy dissipation in solar flares. The governing parameters are suggested on theoretical grounds and shown to be consistent with solar flare observations. The flare electron flux, differential in the non-relativistic electron kinetic energy E, is predicted to scale as E - 3 . This scaling is in agreement with RHESSI measurements of the hard X-ray flux that is generated by deka-keV electrons, accelerated in intense solar flares.

Particle knockout scattering experiments1,2 are fundamental for mapping the structure of atomic nuclei2–6, but their interpretation is often complicated by initial- and final-state interactions of the incoming and scattered particles1,2,7–9. Such interactions lead to reduction in the scattered particle flux and distort their kinematics. Here we overcome this limitation by measuring the quasi-free scattering of 48 GeV c–1 12C ions from hydrogen. The distribution of single protons is studied by detecting two protons at large angles in coincidence with an intact 11B nucleus. The 11B detection suppresses the otherwise large distortions of reconstructed single-proton distributions induced by initial- and final-state interactions. By further detecting residual 10B and 10Be nuclei, we also identified short-range correlated nucleon–nucleon pairs9–13 and provide direct experimental evidence for separation of the pair wavefunction from that of the residual many-body nuclear system9,14. All measured reactions are well described by theoretical calculations that include no distortions from the initial- and final-state interactions. Our results showcase the ability to study the short-distance structure of short-lived radioactive nuclei at the forthcoming Facility for Antiproton and Ion Research (FAIR)15 and Facility for Rare Isotope Beams (FRIB)16 facilities, which is relevant for understanding the structure and properties of nuclei far from stability and the formation of visible matter in the Universe. Initial- and final-state interactions distort the kinematics in particle knockout scattering experiments, complicating their interpretation. These effects are suppressed by detecting 11B nuclei in quasi-free scattering of 12C ions from hydrogen.

Enthalpies of dissolution are found for crystalline racemic tartaric and glutaric acids and isatin in water and in potassium hydroxide solutions at 298.15 K via direct calorimetry. The protolytic equilibria in isatin aqueous solutions are studied at 298.15 K and ionic strengths of 0.5 (relative to potassium nitrate) by potentiometric means. Standard enthalpies of formation are calculated for racemic tartaric and glutaric acids, isatin, and the products of their dissociation in aqueous solutions.

The enthalpies of complexation of glycine (HGly±) with Nd3+ and La3+ ions at 298.15 K and at an ionic strength of 0.5 (KNO3) are determined by means of calorimetry. The thermodynamic characteristics of the reactions of formation are calculated for NdGly2+, NdGly 2 + , LaGly2+, and LaGly 2 + complexes.

Complexation between ethylenediamine-N,N'-disuccinic acid (Н4Y, EDDS) and Er3+, Yb3+, and Lu3+ ions in aqueous solutions is studied by calorimetry and pH measurements. The thermodynamic parameters (logK, ΔrG, ΔrH, and ΔrS) of formation of LnY–and LnHY complexes at 298.15 K and ionic strength I = 0.5(KNO3) are determined. Changes in the thermodynamic parameters of reactions while moving along the lanthanide series are discussed.

The enthalpies of complex formation of L-asparagine (HAsn±) with Nd3+ and La3+ ions are determined calorimetrically at 298.15 K and an ionic strength of 0.5 (KNO3). The thermodynamic characteristics of the formation of the NdAsn2+, NdAsn2+, LaAsn2+, and LaAsn2+ complexes are calculated.

The thermodynamic characteristics of complexation between ethylenediamine-N,N'-disuccinic acid (H4Y; EDDA) and Ho3+ ion were determined calorimetrically and potentiometrically at 298.15 K and ionic strengths of 0.1, 0.5, 1.0, and 1.5 (KNO3). The logK, ΔrG, ΔrH, and ΔrS values for the formation of HoY– and HOHY complexes were calculated at the studied and zero ionic strength values. The changes in thermodynamic parameters of the reactions are discussed.

We explore analytical techniques for modeling the nonlinear cosmic ray transport in various astrophysical environments which is of significant current research interest. While nonlinearity is most often described by coupled equations for the dynamics of the thermal plasma and the cosmic ray transport or for the transport of the plasma waves and the cosmic rays, we study the case of a single but nonlinear advection-diffusion equation. The latter can be approximately solved analytically or semi-analytically, with the advantage that these solutions are easy to use and, thus, can facilitate a quantitative comparison to data. In the present study, we extend our previous work in a twofold manner. First, instead of employing an integral method to the case of pure nonlinear diffusion, we apply an expansion technique to the advection-diffusion equation. We use the technique systematically to analyze the effect of nonlinear diffusion for the cases of constant and spatially varying advection combined with time-varying source functions. Second, we extend the study from the one-dimensional, Cartesian geometry to the radially symmetric case, which allows us to treat more accurately the nonlinear diffusion problems on larger scales away from the source.

The unique pelletized cold neutron moderator CM-202 at the IBR-2 reactor was put into test operation and have already worked more than 2000 hours. Normal, fast and trouble-free operation of the cryogenic moderator requires strict adherence to technological conditions (fast charging and discharging of moderator chamber, maintenance of required temperature and pressure at different parts of cryogenic system). The system of control and measuring equipment, designed for cryogenic moderator of the IBR-2 reactor, satisfies all the requirements and is simple to use. Access to the system of measuring instruments is organized via network. The working cycles of moderator confirmed the reliability and stable operation of the whole control system.

Thermodynamic parameters of the complex formation reactions of ethylenediamine-N,N′-disuccinic acid (H4Y) with La3+, Ce3+, Pr3+, and Nd3+ ions are determined by means of calorimetry and pH-metry in aqueous solutions at 298.15 K and ionic strength I = 0.5 (KNO3). Values of logK, ΔrG, ΔrH, and ΔrS are calculated for reactions of LnY- and LnHY complex formation. Changes in the thermodynamic parameters of reactions in the lanthanides series are discussed.

Thermodynamic parameters of the complexation reactions between ethylenediamine-N,N′-disuccinic acid (H4Y) and Nd3+ ions at 298.15 K and ionic strengths of 0.1, 0.5, 1.0, 1.5 (KNO3) are determined by means of calorimetry and pH-metry. The values (logK, ΔrG, ΔrH, ΔrS) of the formation reactions of NdY− and NdHY complexes are calculated at the investigated and zero values of ionic strength. The change in the thermodynamic parameters of the reactions is discussed.

The formation of a current sheet in a weakly collisional plasma can be modelled as a finite-time singularity solution of magnetohydrodynamic equations. We use an exact self-similar solution to confirm and generalise a previous finding that, in sharp contrast to two-dimensional solutions in standard MHD, a finite-time collapse to a current sheet can occur in Hall MHD. We derive a criterion for the finite-time singularity in terms of initial conditions, and we use an intermediate asymptotic solution for the evolution of an axial magnetic field to obtain a general expression for the singularity formation time. We illustrate the analytical results by numerical solutions.

Data analysis and theoretical arguments support magnetic reconnection in a chromospheric current sheet as the mechanism of the observed photospheric magnetic flux cancellation on the Sun. Flux pile-up reconnection in a Sweet{Parker current sheet can explain the observed properties of canceling magnetic features, including the speeds of canceling magnetic fragments, the magnetic uxes in the fragments, and the flux cancellation rates, inferred from the data. It is discussed how more realistic chromospheric reconnection models can be developed by relaxing the assumptions of a negligible current sheet curvature and a constant height of the reconnection site above the photosphere.

An exact self-similar solution is used to investigate current sheet formation at a magnetic neutral line in incompressible Hall magnetohydrodynamics. The collapse to a current sheet is modelled as a finite-time singularity in the solution for electric current density at the neutral line. We establish that a finite-time collapse to the current sheet can occur in Hall magnetohydrodynamics, and we find a criterion for the finite-time singularity in terms of the initial conditions. We derive an asymptotic solution for the singularity formation and a formula for the singularity formation time. The analytical results are illustrated by numerical solutions, and we also investigate an alternative similarity reduction. Finally, we generalise our solution to incorporate resistive, viscous and electron inertia terms.

The authors have identified priority units – target neuroprotective therapy aimed at restoring the ratio NO/glutathione restored. For this purpose, animals with acute cerebral blood flow (stroke) were injected modulator selenium-dependent glutathione peroxidase medicament "Selenaza" in various doses. In the experiment, the authors used the model of bilateral occlusion of the common carotid arteries – by type of ischemic stroke to Wistar rats. It has been shown that the administration of different dosages "Selenaza" significantly reduces stress marker nitrosating stress - nitrotyrosine, improves the reduced glutathione and glutathione peroxidase enzyme, modifies thiol-disulfide equilibrium in the direction of its reduced forms. According to effect – dose dependence, the concentrations of sodium selenite were calculated ED50 drug "Selenaza", it was 50 ug/ml. Conclusions: These results suggest that selenium protects neurons against hypoxic/ischemic damage by reducing oxidative stress, restoring mitochondrial functional activities, as well as increase levels of reduced glutathione and glutathione peroxidase and reduce markers of nitrosating stress- nitrotyrosine.

One of the main tasks of the NICA/MPD physics program is the study of the strangeness production in nuclear collisions. In this paper the MPD detector performance is presented for measurements of K 0 -mesons, $$\Lambda (\bar \Lambda )$$ -hyperons and hypertritons in central Au + Au collisions at NICA energies.

The thermodynamic parameters of the formation of the complexes of ethylenediamine-N,N′-disuccinic acid (H4Y) with Sm3+ ion are determined by means of calorimetry and measuring pH at 298.15 K and ionic strengths of 0.5, 1.0, and 1.5 (KNO3). The values of logK, ΔrG, ΔrH, and ΔrS are calculated for the formation of SmY− and SmHY complexes at fixed and zero values of ionic strength. The resulting values are interpreted.

The changes in oxidative status indicators in patients with newly diagnosed HIV/AIDS-associated pulmonary tuberculosis after the treatment depending on the course of the therapy were evaluated. It was found the increasing in the levels of protein peroxidation markers in spontaneous and induced oxidation and of lipid peroxidation markers in patients who treated with standard anti-TB and antiretroviral therapy in the dynamics. Its indicates the rise of the oxidative stress severity and disruption of adaptive-compensatory mechanisms, that exacerbates the disease. There were decreased levels of oxidative stress markers in dynamics and in comparison with indicators of other patients after 3 months of treatment in patients, who received the additional treatment with additional pathogenetic therapy with the inclusion of Contrycal, Glutoxim and laser therapy. The antioxidant protection indicators in patients, who received the additional pathogenetic treatment returned to normal or increased in the dynamics and these levels were higher, than that of other patients. In patients, treated with standard therapy, most indicators decreased in dynamics and in comparison with rates in control patients, and patients from the1 group. This suggests an imbalance in the oxidative status in the body after the standard treatment appointment and necessity of its pathogenetic correction.

We study the process of magnetic field annihilation and reconnection in simulations of magnetised solar photosphere and chromosphere with magnetic fields of opposite polarities and constant numerical resistivity. Exact analytical solutions for reconnective annihilations are used to interpret the features of magnetic reconnection in simulations of flux cancellation in the solar atmosphere. We use MURaM high-resolution photospheric radiative magneto-convection simulations to demonstrate the presence of magnetic field reconnection consistent with the magnetic flux pile-up models. Also, a simulated data-driven chromospheric magneto-hydrodynamic simulation is used to demonstrate magnetic field and flow structures, which are similar to the ones theoretically predicted. Both simulations demonstrate flow and magnetic field structures roughly consistent with accelerated reconnection with magnetic flux pile-up. The presence of standard Sweet-Parker type reconnection is also demonstrated in stronger photospheric magnetic fields., Comment: 7 pages, 6 figures. Resubmitted after taking into account the referee's comments

Quantitative models of sunspot and starspot decay predict the timescale of magnetic diffusion and may yield important constraints in stellar dynamo models. Motivated by recent measurements of starspot lifetimes, we investigate the disintegration of a magnetic flux tube by nonlinear diffusion. Previous theoretical studies are extended by considering two physically motivated functional forms for the nonlinear diffusion coefficient $D$: an inverse power-law dependence $D \propto B^{-\nu}$ and a step-function dependence of $D$ on the magnetic field magnitude $B$. Analytical self-similar solutions are presented for the power-law case, including solutions exhibiting "superfast" diffusion. For the step-function case, the heat-balance integral method yields approximate solutions, valid for moderately suppressed diffusion in the spot. The accuracy of the resulting solutions is confirmed numerically, using a method which provides an accurate description of long-time evolution by imposing boundary conditions at infinite distance from the spot. The new models may allow insight into differences and similarities between sunspots and starspots., Comment: 12 pages, 5 figures, to appear in the Astrophysical Journal (accepted 11 November 2016)

The enthalpies of complexation of lead(II) and cobalt(II) with N-(carboxymethyl)aspartic acid (H3Y) were determined calorimetrically at 298.15 K within a wide ionic strength range (KNO3). The thermodynamic characteristics of formation of the CoY2- and PbY2− complexes were calculated at non-zero and zero ionic strengthes. The explanation of the obtained values is given.

Enthalpies of complex formation between N,N-bis(carboxymethyl)aspartic acid (H4Y) with Co2+ ion at 298.15 K are determined by calorimetry over a wide range of ionic strengths (KNO3). Thermodynamic characteristics of the formation reactions of the complexes CoY2−, CoY 2 6− , and Co(OH)Y3− are calculated at zero and other values of ionic strength. The obtained values are interpreted.

The enthalpies of complexation between N,N-bis(carboxymethyl)aspartic acid (H4Y) and the Pb2+ ion at 298.15 K were determined from calorimetric data for a wide range of the ionic strengths (KNO3). The thermodynamic characteristics ΔH, ΔG, and ΔS, of formation of the complexes PbHY− and PbY2− were calculated for zero and fixed ionic strengths. The results obtained were interpreted.

The equilibrium constants and heats of formation of complexes of N,N-bis(carboxymethyl)aspartic acid (H4Y) with Cd2+ ions at 298.15 K and ionic strengths of 0.2, 0.5, and 1.0 (KNO3) were determined by potentiometric titration and calorimetrically. The thermodynamic characteristics of formation of the CdY2− complex at fixed and zero ionic strength values were calculated. The values obtained were interpreted.

Global energy losses associated with transient magnetic reconnection in a viscous resistive plasma are examined. The Braginskii stress tensor is used to model the plasma viscosity for conditions typical of the solar corona. Analytic arguments are used to show that the large-scale advective flows associated with magnetic merging are likely to generate significant viscous losses. It is pointed out that the development of a visco-resistive reconnection scale, predicted for the classical shear viscosity, is not expected in the more realistic case of the Braginskii viscosity. Numerical simulations of planar coalescence merging show that viscous losses should easily dominate resistive losses for physically plausible parameters in flaring regions. Our computations imply that flare-like rates exceeding 1029 erg s–1 can be achieved under plausible coronal conditions.

Formation of solar filament channels by photospheric magnetic reconnection is considered. A magnetohydrodynamic model for magnetic merging, driven by converging convective motions in the photosphere, is presented. Evolution of the axial magnetic field in a channel is analyzed. An exact time-dependent analytical solution for the field profile in a steady stagnation-point flow is derived. The maximum magnetic field in the channel is determined, and its dependence on the reconnection inflow speed is discussed. The quantitative results show that the maximum axial magnetic field in a forming channel is an indicator of the photospheric reconnection rate, in agreement with recent solar observations and laboratory experiments.

Recent theoretical studies suggest that the nonlinearity of three-minute velocity oscillations at each atmospheric level can be quantified by the two independent parameters—the steepening parameter and the velocity amplitude parameter. For the first time, we measured these two parameters at different atmospheric levels by analyzing a set of spectral lines formed at different heights of sunspots ranging from the temperature minimum to the transition region. The spectral data were taken by the Fast Imaging Solar Spectrograph of the Goode Solar Telescope, and by the Interface Region Imaging Spectrograph. As a result, from the wavelet power spectra of the velocity oscillations at different heights, we clearly identified the growth of the second harmonic oscillations associated with the steepening of the velocity oscillation, indicating that higher-frequency oscillations of periods of 1.2 to 1.5 minutes originate from the nonlinearity of the three-minute oscillations in the upper chromosphere. We also found that the variation of the measured nonlinearity parameters is consistent with the theoretical expectation that the nonlinearity of the three-minute oscillations increases with height, and shock waves form in the upper chromosphere. There are, however, discrepancies as well between theory and observations, suggesting the need to improve both theory and the measurement technique.

The enthalpies of complex formation between iminodisuccinic acid (H4L) and the Cd2+ ion were determined calorimetrically at 298.15 K and ionic strengths 0.5, 1.0, and 1.5 (KNO3). The thermodynamic characteristics of formation of CdL2− and CdHL− complexes at fixed and zero ionic strength values were calculated.

Photospheric magnetic flux cancellation on the Sun is generally believed to be caused by magnetic reconnection occurring in the low solar atmosphere. Individual canceling magnetic features are observationally characterized by the rate of flux cancellation. The specific cancellation rate, defined as the rate of flux cancellation divided by the interface length, gives an accurate estimate of the electric field in the reconnecting current sheet. We have determined the specific cancellation rate using the magnetograms taken by the Solar Optical Telescope (SOT) aboard the Hinode satellite. The specific rates determined with SOT turned out to be systematically higher than those based on the data taken by the Michelson Doppler Imager (MDI) aboard the Solar and Heliospheric Observatory. The median value of the specific cancellation rate was found to be 8 × 106 G cm s-1—a value four times that obtained from the MDI data. This big difference is mainly due to a higher angular resolution and better sensitivity of the SOT, resulting in magnetic fluxes up to five times larger than those obtained from the MDI. The higher rates of flux cancellation correspond to either faster inflows or stronger magnetic fields of the reconnection inflow region, which may have important consequences for the physics of photospheric magnetic reconnection.

Aims. We consider viscous and resistive energy dissipation in the flaring solar corona. Methods. We compute energy dissipation rates, associated with magnetic merging in three dimensions. We examine an exact 3D solution for steady magnetic merging in a viscous resistive incompressible plasma. We use the Braginskii stress tensor to model viscous effects and derive scalings for the resistive and viscous dissipation rates. We evaluate the dissipation rates for typical parameters of solar active regions. Results. Large-scale advective flows required to sustain resistive current sheets are shown to be associated with significant viscous losses. For plausible dimensionless resistivities (inverse Lundquist numbers), whether classical η ≤ 10 −14 or anomalous η ≤ 10 −8 , viscous loss rates greatly exceed the resistive loss rates of the current layer and can approach flare-like rates of 10 28 erg s −1 .

Steady magnetic reconnection in the framework of incompressible Hall magnetohydrodynamics is considered. The principal role of the Hall effect in the formation of the structure of the reconnecting current sheet is emphasized. Analytical expressions for the velocity and the magnetic field in the sheet are derived, based on the approximation of a weak two dimensionality of the planar components of the solution. The analytical solution illustrates key features of Hall magnetic reconnection, including the reconnection rate enhancement and the sheet thinning due to the Hall effect, the presence of a quadrupolar axial (out-of-the-plane) magnetic field that controls the geometry of the reconnecting planar magnetic field, and the dynamical coupling of the axial and planar components of the solution, with the coupling strength that is proportional to the ion skin depth. Scalings for the sheet thickness, width, and the reconnection inflow and outflow speeds in terms of the electric resistivity and the axial magnetic field are determined. Implications of the results for fast magnetic reconnection in a weakly collisional plasma of the solar corona are discussed.

Aims. Predicted and observed signatures of magnetic reconnection in the solar chromosphere are discussed. Methods. Compressible reconnection scalings for the Sweet-Parker current sheet in the chromosphere are derived, which generalize earlier treatments by including both the Lorentz force and the pressure gradient in the reconnection outflow as possible drivers of reconnection jets. The theoretical scalings were tested against the measured speed, density, and temperature of an extreme-ultraviolet jet, observed with TRACE. Model predictions for the reconnection jet parameters as functions of height above the solar photosphere were computed. Results. The predicted variation of reconnection jet parameters with height appears to correspond to the observed wide range of parameters of chromospheric jet-like features.

The enthalpies of complex formation between ethylenediamine-N,N′-disuccinic acid (H4A) and Cd2+ ions were determined calorimetrically at 298.15 K and ionic strengths of 0.5, 1.0, and 1.5 (KNO3). The thermodynamic characteristics of formation of the CdA2− and CdHA− complexes at fixed and zero ionic strengths were calculated. The values obtained were interpreted.