The following paper reviews the results of 2017-2019 studies of the influence of types and methods of micronutrient fertilizers application: zinc sulfate, cobalt sulfate and ammonium molybdate on the ...growth, development and productivity of corn. The studies were conducted in the southern agricultural zone of Amur region on the experimental field of Far Eastern State Agrarian University, located in the village of Gribskoye (Blagoveshchensk district). The object of research was a hybrid Mashuk 175MV (FAO 170) - an early-ripening three-linear hybrid of universal use. Treatment of seeds and plants of corn by microfertilizers was carried out using a solution with a concentration of 0.1%. As a result of studies, it was found that the use of microfertilizers during plants vegetation more effectively affects the accumulation of dry matter than seeds treatment and double treatment of seeds and vegetative plants. When seeds treatment, the most effective variant is the combined use of microelements and when treatment during vegetation is the variant with using cobalt. The use of microfertilizers showed a significant increase in leaf surface area for all variants relative to the background variant. The greatest effect was shown by the variant with the use of cobalt in the seeds treatment and spraying vegetation of plants. The combined use of microfertilizers in the seeds treatment and spraying during vegetation has shown a good increase the yield of green mass of corn. The greatest effect was shown in seeds treatment by cobalt and spraying the plants during vegetation.
Context. The projection factor p is the key quantity used in the Baade-Wesselink (BW) method for distance determination; it converts radial velocities into pulsation velocities. Several methods are ...used to determine p, such as geometrical and hydrodynamical models or the inverse BW approach when the distance is known. Aims. We analyze new HARPS-N spectra of δ Cep to measure its cycle-averaged atmospheric velocity gradient in order to better constrain the projection factor. Methods. We first apply the inverse BW method to derive p directly from observations. The projection factor can be divided into three subconcepts: (1) a geometrical effect (p0); (2) the velocity gradient within the atmosphere (fgrad); and (3) the relative motion of the optical pulsating photosphere with respect to the corresponding mass elements (fo−g). We then measure the fgrad value of δ Cep for the first time. Results. When the HARPS-N mean cross-correlated line-profiles are fitted with a Gaussian profile, the projection factor is pcc−g = 1.239 ± 0.034(stat.) ± 0.023(syst.). When we consider the different amplitudes of the radial velocity curves that are associated with 17 selected spectral lines, we measure projection factors ranging from 1.273 to 1.329. We find a relation between fgrad and the line depth measured when the Cepheid is at minimum radius. This relation is consistent with that obtained from our best hydrodynamical model of δ Cep and with our projection factor decomposition. Using the observational values of p and fgrad found for the 17 spectral lines, we derive a semi-theoretical value of fo−g. We alternatively obtain fo−g = 0.975 ± 0.002 or 1.006 ± 0.002 assuming models using radiative transfer in plane-parallel or spherically symmetric geometries, respectively. Conclusions. The new HARPS-N observations of δ Cep are consistent with our decomposition of the projection factor. The next step will be to measure p0 directly from the next generation of visible interferometers. With these values in hand, it will be possible to derive fo−g directly from observations.
In this work, we significantly extend our new approach for analyzing nucleation kinetics below the glass transition, Tg, which considers the structural relaxation effect. Using a 5BaO·8SiO2 (B5S8) ...glass, we showed a significant stepwise change in the nucleation relaxation time, τsr, with temperature in the Tg region, in contrast with the expected monotonous variation with temperature: τsr is four times shorter for the supercooled liquid than for the glass. Then, using a combination of new experimental data and theoretical (analytical and numerical) analyses, we advance an interpretation within the Classical Nucleation Theory (CNT) framework that brings together the nucleation rates in the T > Tg and T < Tg ranges. We show once more that the so-called “breakdown” of the CNT is merely the result of underestimated nucleation rates due to incomplete glass relaxation during limited experimental nucleation times, confirming our recent findings for Li2O·2SiO2 and 2Na2O·CaO·3SiO2. Finally, for the first time, we also show that due to the almost complete crystallization of the B5S8 glass, and likely of other glasses that exhibit sufficiently high nucleation and growth rates, the relaxation process cannot be finished in the low-temperature range and the ultimate steady-state nucleation regime cannot be reached. These combined results shed light on the complex nucleation behavior below Tg.
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To cover the so-called terahertz gap in powerful sources of coherent electromagnetic waves, a second-harmonic gyrotron operating in a 10 T liquid helium-free superconducting magnet has been designed, ...manufactured, and tested. With an operating voltage of 15 kV and a beam current of 0.6 A, the gyrotron generated coherent continuous-wave radiation at a frequency of 0.526 Terahertz with an output power of 250 Watts and an efficiency of 2.7%.
Четыре портрета без ретуши Fokin, Pavel Evgenyevich
Neizvestnyj Dostoevskij,
2020, Volume:
7, Issue:
3
Journal Article
Peer reviewed
Open access
Researchers are still raising questions related to the time and place of shooting of certain portraits in the scarce photographic iconography of F. M. Dostoevsky. First of all, this pertains to a set ...of early photographs, whose dating ranges between 1857 and 1863, according to various sources. The article offers new arguments in favor of attributing several portraits of F. M. Dostoevsky to 1859. This refers to photographs that captured an image of F. M. Dostoevsky that is unusual for most of his admirers, namely, without a beard. Two of them were taken in Semipalatinsk by the photographer S. A. Leibin, while in one of them F. M. Dostoevsky was captured together with the Kazakh educator Ch. Ch. Valikhanov, whom he befriended during the years of his exile. Another photo has not been precisely attributed. A comprehensive analysis of the details depicted on them, the facts of the biography of Ch. Ch. Valikhanov and the letters of F. M. Dostoevsky allows to date the Semipalatisk photographs with greater accuracy. The article proposes that another one of the portraits taken in Tver was carried out simultaneously with the shooting of the portrait of M. M. Dostoevsky. A comprehensive examination of various details and circumstances also leads to the same conclusions. To date, only a few copies of photographs with Ch. Ch. Valikhanov and a photograph allegedly taken in Tver are known. The original solitary portrait made in Semipalatinsk has been lost. The conducted research allows to assert that other copies of these photographs may exist. The proposed conclusions are made on the basis of a study of the originals of photographs in the collection of The V. I. Dahl State Museum of the History of Russian Literature.
The advent of ultra-large libraries of drug-like compounds has significantly broadened the possibilities in structure-based virtual screening, accelerating the discovery and optimization of ...high-quality lead chemotypes for diverse clinical targets. Compared to traditional high-throughput screening, which is constrained to libraries of approximately one million compounds, the ultra-large virtual screening approach offers substantial advantages in both cost and time efficiency. By expanding the chemical space with compounds synthesized from easily accessible and reproducible reactions and utilizing a large, diverse set of building blocks, we can enhance both the diversity and quality of the discovered lead chemotypes. In this study, we explore new chemical spaces using reactions of sulfur(VI) fluorides to create a combinatorial library consisting of several hundred million compounds. We screened this virtual library for cannabinoid type II receptor (CB2) antagonists using the high-resolution structure in conjunction with a rationally designed antagonist, AM10257. The top-predicted compounds were then synthesized and tested in vitro for CB2 binding and functional antagonism, achieving an experimentally validated hit rate of 55%. Our findings demonstrate the effectiveness of reliable reactions, such as sulfur fluoride exchange, in diversifying ultra-large chemical spaces and facilitate the discovery of new lead compounds for important biological targets.
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