The dependence of lead silicate glass color, applied using copper(
ii
) ions, on lead content in the glass, the nature of the alkali metal, and copper content was studied. It was shown that the ...principal contribution to the color is made by the shift of the fundamental absorption edge, which correlates with the amount of lead and copper ions. According to EPR results for glasses with the studied compositions, copper ions have a tetragonally distorted octahedral coordination environment, which does not change considerably with composition. The Cu
ii
d—d-transition bands also do not undergo considerable changes.
We analyzed the research data on antitumor effects of a wide range of ferrocene compounds and discussed possible mechanisms of their bioactivities. Current trends in the study of anticancer effects ...of ferrocene derivatives were considered. Promising ways in the design of low-toxicity anticancer ferrocene-based drugs of new generation were outlined.
—
Samples of composites of ultra-high molecular-weight polyethylene (UHMWPE) with addition of 2.24, 5, and 8.1 wt % quasicrystalline Al–Cu–Fe alloy have been prepared by in situ polymerization. ...Friction and wear tests are performed, the physico-mechanical tensile properties are studied, and the thermophysical properties are investigated using differential scanning calorimetry and thermogravimetric analysis. The surface morphology of composite samples, both subjected and not subjected to friction, has been investigated by scanning electron microscopy. It is found that addition of a quasicrystalline Al–Cu–Fe filler in amount of 2.24 wt % improves the tribological characteristics of UHMWPE: under a load of 50 N and at friction duration of 8 h, the wear decreases by a factor of 3, and the friction coefficient decreases by 20%.
The paper is devoted to solving the problem of reducing the power consumption of programmable logic integrated circuits (hereinafter FPGAs) by software methods. The solution of this issue is ...especially relevant for various types of radio engineering systems, which include autonomous and portable stations. At the beginning of the paper, the theoretical foundations of FPGA consumption are given: types of consumption (static and dynamic) and influencing parameters (switching logic, the physical foundations of the integrated circuit and other internal resources). The work is explained and methodological guidelines are given for the specialized built-in PowerAnalyzer utility of the Quartus II software development environment, the main indicators with which the utility works are explained: toggle rate (switching frequency) and static probability (the probability of finding a signal in a stable state "0" or "1"). The following is a Pipelinning method for eliminating the racing effect (the effect in which signals passing through an element/crystal reach the destination point with different time delays). The essence of the method is that a register is set at the output of the element that creates the delay. The register stores the value at the input at the CLK clock frequency, so random switching of the previous circuit element will be ignored. This eliminates the effect of racing and reduces the dynamic consumption of the circuit. At the end of the paper, the results of reducing energy consumption using the above methods are presented. The greatest gain is observed when minimizing consumption, when a large number of logic elements on the FPGA chip are involved, as well as when high-frequency operation occurs. This is due to the fact that when using the methods of switching off the clock frequency, we get rid of a large number of switches between the states of logic elements (the higher the frequency, the more such state switches per unit of time). If the number of occupied elements is more than 50%, we get a reduction in power consumption of more than 5%, and if the number of occupied elements is 75%, then we get a gain of about 14%.
In Russian Arctic seas, observations of surface methane concentrations (CH
4
), ozone, nitrogen and carbon oxides, as well as the content of
isotope and black carbon (BC, soot aerosol), were carried ...out from onboard of the R/V
Academician Mstislav Keldysh
. The areas of local methane releasing from bottom sediments were investigated. It was shown that the studied methane releasing on the Arctic shelf are of a local nature and, on the whole, insignificantly affect the composition of the atmosphere in the region. The average concentration of methane in the surface air in the Arctic seas is mainly determined by large-scale processes of air mass transfer. An analysis of the distribution of black carbon along the route of the vessel was carried out. It was found that the excess in the concentration of black carbon over the background values is observed occasionally during advection of air masses from the mainland and from the areas of associated gases burning and forest fires. The effect of emissions from a ship’s chimney on the data obtained was analyzed.
Complexes {(Zn(Bbtm)(H
2
O)
4
(NO
3
)
2
}
n
(
I
) and Cu(Вbtm)(NO
3
)
2
n
(
II
) are formed due to the reactions of solutions of zinc and copper(II) nitrates with the ...bis(1,1'-1,2,3-benzotriazolyl)methane ligand (Bbtm). Their crystal structures are determined by X-ray diffraction analysis (CIF files ССDС nos. 1963126 (
I
) and 1963127 (
II
)). Complex
I
is a linear metal-organic framework (1D-MOF) in which the octahedral coordination of the central atom is provided by four water molecules and two nitrogen atoms of two Bbtm molecules in the
trans
position. In the structure of complex
II
, the coordination sphere of copper contains two nitrogen atoms of the Вbtm ligands and four oxygen atoms of two nitrate anions, one of which is bridging like the Вbtm ligand. This makes it possible to describe the structure of complex
II
as 3D-MOF. The luminescence spectra are recorded for earlier undescribed compound
I
. The emission maximum is observed at 363 nm. Compound
I
is also tested as a catalyst for the cycloaddition of СО
2
to epoxides. The synthesized MOF efficiently catalyzes the cycloaddition reactions for both monosubstituted and disubstituted epoxides.
The early 21st century saw increased eruption activity of major volcanoes in the Northern Group of Kamchatka, namely, Sheveluch, Klyuchevskoy, Bezymianny, and the Tolbachik Fissure Zone. The growth ...of an extrusive dome on Sheveluch andesitic volcano has occurred, with the dome reaching a height of 600 m after 38 years of nearly uninterrupted eruption activity. An 8-year period of relative quiet was followed by ten summit eruptions and two lateral vent openings on the Klyuchevskoy basaltic volcano. Explosive–effusive eruptions were observed nearly every year on the Bezymianny andesitic volcano. A 36-year quiet period gave way to a new eruption in the Tolbachik regional fissure zone.
Abstract
The article is devoted to the problems of the Earth’s climate change as an object of environmental protection and an object of international cooperation. In the implementation of ...environmental and legal support for climate preservation by the countries of the European Union and the Russian Federation, characteristic features are manifested, which are due to the similarity of specific tasks. The aim of the study is to analyze the prospects for the development of the institute of environmental monitoring associated with the dynamic implementation of the latest information and communication methods and systems in the implementation of mechanisms that prevent and stabilize changes in the Earth’s climate. The article analyzes the main program and legal documents of Denmark, Germany, France and Russia, their variability in determining special approaches to the study of climate change. Attempts to create an adequate system of convergence of national and international legal regulation in order to determine modern legal approaches to the problems of global warming have been studied and discussed in detail. Each of the represented countries has a national strategy for achieving carbon neutrality in the context of creating a circulating model of the modern economy. It is noted that for most of the topical issues, these strategies have common approaches: scientifically based methods of environmental monitoring, the introduction of innovative digital technologies and science-intensive information and communication methods and systems.
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