The treatment of porphyry copper ores which are considered an important source of non-ferrous and precious metals requires the development of high-efficient technologies for metal extraction ensuring ...a low impact on the environment. The goal of the present work was to study the feasibility of a biohydrometallurgical approach for the processing of Kajaran porphyry copper-molybdenum ore as no attempt was done previously for microbiological processing of the mentioned ore. Sulfide and oxide ore samples used for bioleaching tests contained 0.63 and 0.77% copper, 1.81 and 1.55% iron, and 0.14 and 0.023% molybdenum, respectively. The experiments were carried out in 250 ml flasks under shaking conditions. Indigenous and adapted bacterial consortia 'Kashen' and 'Kavart' were used for bioleaching of ore samples. The objectives of the study were to investigate the influence of particle size (PS), pulp density (PD), and adaptation of the bacterial cultures to the process of copper extraction. The composition of feed material and leaching residues from bioleaching experiments were characterized by geochemical, mineralogical, and particle analyses. As a result, nearly complete bioleaching of the sulfide and oxide ores could be achieved after the optimization of the experiments. The particle analyses showed an enhanced liberation of chalcopyrite particles out of the intergrown ore under bioleaching conditions compared to the abiotic controls and hence an improved Cu solubilization under bioleaching conditions.
The results of experimental observation of coherent Cherenkov radiation from picosecond electron bunches traveling along the axis of a dielectric loaded cylindrical waveguide are presented. ...Experiments have been performed at the AREAL linear accelerator at the CANDLE Synchrotron Research Institute. The angular distribution of radiation from 3.7 MeV electron bunches passing through cylindrical quartz sample is investigated. In the second part of the paper we argue that, by tuning the ratio of the distance between the bunches crossing the plate inside the waveguide and the radius of the waveguide, one can further increase the intensity of quasi-coherent Cherenkov radiation on several neighboring modes.
Previously synthesized ethyl 2-benzamido-4-(1,4-benzodioxan-2-yl)thiophene-3-carboxylates were cyclized to 2-aryl-3-aminothieno2,3-
d
pyrimidin-4(1
H
)-ones by the action of hydrazine hydrate. The ...condensation of ethyl 2-amino-4-(1,4-benzodioxan-2-yl)thiophene-3-carboxylate with chloroacetyl chloride gave the corresponding N-substituted 2-chloroacetamide which reacted with piperidine and morpholine to produce 2-aminoacetamides, and the latter were also subjected to cyclization with hydrazine hydrate to obtain 3-aminothienopyrimidin-4-one derivatives. The synthesized compounds were tested for antihypoxic activity.
The review presents the history of the creation and work of the Scientific Council “Cybernetics” (SCC)—the center for development of cybernetics in the USSR and Russia. The Council’s activity is ...covered as a structure that coordinates scientific and technical activity in cybernetics in the country via a system of sections: about 16 public and professional bodies involving thousands of specialists. Brief information about the sections is given. The chronology of development of the SCC is discussed, in particular, information about its chairmen, starting with the renowned organizer of research and development, Academician and Admiral Axel Ivanovich Berg and the following academicians: B.N. Petrov, O.M. Belotserkovsky, A.P. Ershov, E.P. Velikhov, B.V. Bunkin, and Yu.I. Zhuravlev. The SCC’s publishing activity is briefly reviewed. The second function, built into the SCC from its onset, is as a research institute conducting its own research on the most pressing scientific problems insufficiently covered by existing structures. Several main areas of research by the SCC itself and its successor, the Axel Berg Institute of Cybernetics and Educational Computing of the Federal Research Center “Computer Science and Control” of the RAS: coding and transmission of information, economic cybernetics, aircraft control, supercomputers, digital technologies in education, mathematical logic and the theory of algorithms, pattern recognition and image analysis, mathematical methods of image analysis, theoretical physics, biomedical cybernetics, and ultrasound imaging. Another function of the SCC is considered: as an incubator of new academic industrially oriented structures and the fate of one of them—the Institute of Cybernetics Problems—is traced.
Based on a joint review and discussion of data on the ignition of aldehyde–oxygen mixtures, initiated by an adsorbed peroxide compound upon heating, and on the heterogeneous interaction between RO
2
...peroxide radicals and an aldehyde, it is concluded that the constant temperature
T
i
of ignition in one range of changes in the amount of peroxide compound is due to the limited number of active centers on its surface because of its saturation with heterogeneous radical reactions.
Advanced Research Electron Accelerator Laboratory (AREAL) is a 50MeV electron linear accelerator project with a laser driven RF gun being constructed at the CANDLE Synchrotron Research Institute. In ...addition to applications in life and materials sciences, the project aims as a test facility for advanced accelerator and radiation source concepts. In this paper, the AREAL RF photoinjector performance, the facility design considerations and its highlights in the fields of free electron laser, the study of new high frequency accelerating structures, the beam microbunching and wakefield acceleration concepts are presented.
Flexible response of the airframe structural elements under operational loads are one of the main sources of fatigue damage accumulation. It is known that fuel sloshing in tanks can change the ...dynamic (frequencies and shapes of natural oscillations) and dissipative properties (oscillation damping decrements) of an elastic system, including partially or completely fuelfilled tanks. It is specified that fuel sloshing in tanks due to the additional oscillation energy dissipation of the elastic system can have a significant impact on both the fatigue and aeroelastic characteristics of aircraft structural elements. Theoretical and experimental studies, applicably to the majority of currently operating transport aircraft, have shown that when modeling dynamic phenomena and solving aeroelasticity problems, fuel can be considered conditionally solidified, which actually does not affect the resultant effect. The advent of modern heavy transport aircraft with a high aspect ratio wing and four engines on pylons under the wing has led to a considerable change in the dynamic picture of the aircraft interaction with the environment. The main feature is that, under this arrangement, the first horizontal bending mode of the wing is embedded in the main flexible modes that determine the dynamic response to external effects. In this case, the model of solidified fuel can have a significant impact on the accuracy of predicting dynamic loads and, as a consequence, on the quantitative characteristics of durability and aeroelasticity. The article presents the results of experimental studies of the impact of fluid sloshing in the tank on the dynamic characteristics (frequencies of natural oscillations and amplitudes of forced oscillations) of the “wing model – fuel tank” system. The design of the experimental installation and the methodology of conducting experiments are described. During the experiment, the tank was partially filled with liquid or full, and horizontal bending modes of the wing model, for which considering liquid sloshing in the tank is the most relevant, were studied. The tank refueling levels are determined at which the maximum effect of the system oscillation damping is achieved due to energy dissipation under liquid sloshing. The effect of various factors (presence of a top cover, internal structural frame, perforation in the structural frame) on the amplitudes and frequencies of forced oscillations is analyzed.
The paper highlights the issues related to the validity and appropriateness of the using of international standards in the processes of accounting and internal audit of the leasing operations. The ...problem, the results of which are presented in this article, is that due to the changes in the Russian legislation there is a necessity for a detailed researching of the possibilities of using of international standards in accounting and internal audit. A brief overview of changes in the Russian legislation relating to the accounting of leasing is presented as a result of the researching, its content and importance is disclosed. The statutes about accounting and internal audit of leasing operations according to the requirements of international standards are also presented.
Cyclization of previously synthesized ethyl 2-amino-4-(1,4-benzodioxan-2-yl)thiophene-3-carboxylate with formamide gave 5-(1,4-benzodioxan-2-yl)thieno2,3-
d
pyrimidin-4(3
H
)-one which was treated ...with phosphoryl chloride in pyridine to obtain the corresponding 4-chloro derivative. The latter reacted with various primary and secondary amines to produce a series of new thieno2,3-
d
pyrimidines containing a pharmacophoric fragment at the 4-position. The reaction of 5-(1,4-benzodioxan-2-yl)-4-chlorothieno2,3-
d
pyrimidine with hydrazine hydrate afforded the corresponding 4-hydrazinyl derivative which was cyclized with formic acid to thieno3,2-
e
1,2,4triazolo1,5-
c
pyrimidine derivative. Antihypoxic properties of the synthesized compounds were studied.
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