Abstract
The present research is aimed at studying the impact of the modern no-till agricultural technology on the development of erosion processes on cultivated arable land in the subzone of the ...southern chernozems of the Volgograd region. Evaluation of the impact of this agricultural technology was based on the analysis and comparison of soil cover in hollows located in the fields cultivated using either the classic technology or the no-till technology. The research methodology is based on combination of remote, field and laboratory methods for studying the soil cover. Analysis and generalization of data obtained in the course of laboratory studies of selected soil samples made it possible to identify a high degree of erosion processes in the hollows located in the fields, which had been cultivated using the no-till technology for three years. Comparison of the values of the content of organic carbon in the zones of removal, transit and accumulation of fine earth indicates the development of water degradation processes in the middle part of the hollows. Thus, for soil samples taken from a depth of 0-10 cm, the value of organic carbon content in the variant of soil tilled using the new technology is 2.6%, while in the variant tilled using the classic technology, this value is equal to 3.1%. The revealed differences in the soil cover of the hollows can be explained by interaction of the patterns of development of erosion-accumulation processes and the features of the no-till technology in specific natural and climatic conditions.
In this study criterion of maximum profit intensity for transportation problems, in contrast to the known criteria of minimum expenses or minimum time for transportation, is considered. This ...criterion synthesizes financial and time factors and has real economic sense. According to the purpose of this paper, the algorithm of solution of such transportation problem is constructed. It is shown that the choice is carried out among Pareto-optimal options, moreover the factor of time becomes defining for the high income from transportation, and the factor of expenses - at low ones. Not absolute but relative changes of numerator and denominator become important when the criterion represents the fraction (in this case - the profit intensity as the ratio of profit to time). Nonlinear generalization of such transportation problem is proposed and the scheme of its solution in a nonlinear case is outlined. Graphic illustrations of Pareto-optimal and optimal solutions of transportation problem by profit intensity criterion are also given.
The results of mapping and assessing the sealing rate of soils in the city of Volgograd (Russian Federation) are presented. Soil mapping is based on the interpretation of satellite photographs with ...further control of its results by field surveys at 35 plots within different functional zones of the city. According to the results of the interpretation of satellite images, the portion of sealed areas determined for the functional zones ranged from 0 to 99%, including soils under buildings and roads. The MapInfoProfessional 10.0 software was used to process the obtained data. Based on the results of this assessment, which was performed for the first time within the new boundaries of the city, we quantified the areas of particular soil types and associations of both natural and anthropogenic origin, as well as the sealing rate of soils. The natural soils in Volgograd are dominated (25.86%) by chestnut soils of various texture and alkalinity 23 (Cambisols and Cambisols (Sodic)), and there are 18.67% of natural surface-transformed textural-carbonate agrozems (Cambisols (Aric, Protocalcic)). The range of anthropogenically transformed soils is wide, including the sealed soils (Ekranic Technosols), urbostratozems (Urbic Technosols), chemically contaminated urbostratozems (Technosols (Toxic)), and quasizems (Urbic Technosols). Anthropogenically transformed soils mostly occur in the eastern part of the city, and natural soils dominate its western part. The total portion of sealed surfaces is 18% of the Volgograd area. The calculation is based on the assessment for particular functional zones of the city. The results can be used to solve problems of spatial planning within the modern functional zones and implementation of works on gardening and landscaping of the urban area.
Abstract
The Volga-Akhtuba floodplain is a unique intrazonal ecosystem of the Lower Volga. For many years, the landscapes of the area suffered from an intensive anthropogenic impact, starting with ...the commissioning of the Volga Hydroelectric Power Plant. Increasing anthropogenic pressure, high ecological value and standing out against the background of semi-desert areas led to the inclusion of this area into the Volga-Akhtuba Floodplain Nature Park in 2000. This article analyses the changes in the functional zoning of the nature park at the beginning of active conservation activities and present. The authors reveal the main hotspots of economic activity represented by agriculture in the region and farmsteads, which include settlements, horticultural societies and their linear infrastructure (road and transport network). In addition, they identify forest ecosystems of particular ecological and aesthetic value. The analysis of the economic impact and distribution of unique forest ecosystems provides an assessment of the changes in the spatial organisation of the area.
The article discusses the problems of accessibility of information about the impact of enterprises on environmental components for stakeholders. Assessing the environmental component of non-financial ...reports allows to analyse the environmental activities of any company and draw appropriate conclusions about the effectiveness of the policies of enterprises. Russian companies, unlike foreign ones, have lower trends to disclose environmentally significant information, but there is a positive trend in placing such information in the public domain. The study analyzed the trend of non-financial reporting following the international recommendations of the Global Reporting Initiative (GRI). In the period June-November 2019, the number of Russian companies reports presented in the international GRI database increased by 10%, with a global dynamics of 1.7%. According to the National Register of the Russian Union of Industrialists and Entrepreneurs, 80% of non-financial reporting is the reports of sustainable development field, the most open are the enterprises of the oil and gas industry and the electric power industry. The study covered 107 negative impact facilities of the 1st category, high and significant risk category, located in the Volgograd region. To assess the openness of regional enterprises, we analyzed their official websites and databases of the rating of environmental business performance. Official sites identified for 72% of facilities demonstrate the predominance of environmentally significant declarative information, it is 87% of analyzed sites. A study of companies' readiness to disclose data on anthropogenic impact for stakeholders used copyright checks and showed the commitment of less than 10% of respondents. Regional companies did not support the initiative on the openness of environmentally significant information, which less than 2% of enterprises publish in the open access, and are not ready to prepare reports on sustainable development following international criteria. Since 2018, the exclusion of quantitative data on the negative impact on specific enterprises as a mandatory component of regional reports on the state of the environment has exacerbated the identified trend.
Experimental and theoretical studies of direct photon production in hadronic collisions essentially expand our insights in multiparticle production mechanisms. These photons are useful probes to ...investigate nuclear matter at all stages of the interaction. Soft photons play a particular role in these studies. Until now we have no explanation for the experimentally observed excess of soft photons. These photons have low transverse momenta GeV/c, . In this domain their yield exceeds the theoretical estimates by 5-8 times. The registration of soft photons at Nuclotron (LHEP, JINR) has been carried out by the electromagnetic calorimeter built by the SVD-2 Collaboration. Soft photon electromagnetic calorimeter was tested at U-70, IHEP (Protvino). For the first time the soft photon yield at interactions of 3.5A GeV/c per nucleon deuterium and lithium beams has been measured. The obtained energy spectra confirm the increased yield of soft photons with their energy less than 50MeV (in the laboratory system) in comparison with theoretical predictions and agree with previous experiments at high-energy interactions. It is planned to continue soft photon study at the future accelerator complex NICA with heavy-ion beams.
Observation of K+→π+π0π0γ decay Artamonov, A. V.; Bychkov, V. N.; Donskov, S. V. ...
The European physical journal. C, Particles and fields,
04/2024, Letnik:
84, Številka:
4
Journal Article
Recenzirano
Odprti dostop
The
K
+
→
π
+
π
0
π
0
γ
decay is observed by the OKA collaboration. About 60 events of the decay observed with signal:noise
≈
1
. The branching ratio obtained by normalization to
K
+
→
π
+
π
0
π
0
is ...measured to be
(
3.7
±
0.9
(
s
t
a
t
)
±
0.3
(
s
y
s
t
)
)
×
10
-
6
for
E
γ
∗
>
10
MeV
. The branching ratio,
γ
energy spectrum and angular distribution are consistent with ChPT prediction.
A high-statistics data sample of the
K
+
decays is recorded by the OKA collaboration. A missing mass analysis is performed to search for a light invisible pseudoscalar axion-like particle (ALP)
a
in ...the decay
K
+
→
π
+
π
0
a
. No signal is observed, and the upper limits for the branching ratio of the decay are calculated. The
90
%
confidence level upper limit changes from
2.5
·
10
-
6
to
2
·
10
-
7
for the ALP mass from 0 to 200 MeV/
c
2
, except for the region of
π
0
mass, where the upper limit is
4.4
·
10
-
6
.
In this work we discuss some problems of polymer physics which require use of the geometrical and topological methods for their solution. Selection of problems is made to provide some balanced view ...between the real physical situations and the mathematical methods which are required for their understanding. We consider both static and dynamic properties of polymer solutions which depend on the presence of entanglements. These include: problems related to polymer collapse, statics and dynamics of individual circular polymers and concentrated polymer solutions, problems related to elasticity of rubbers and gels, motion of polymers through pores, etc. This work serves both as an introduction to the field and as a guide for further study.
Although contact geometry and topology is briefly discussed in V I Arnol'd's book "Mathematical Methods of Classical Mechanics "(Springer-Verlag, 1989, 2nd edition), it still remains a domain of ...research in pure mathematics, e.g. see the recent monograph by H Geiges "An Introduction to Contact Topology" (Cambridge U Press, 2008). Some attempts to use contact geometry in physics were made in the monograph "Contact Geometry and Nonlinear Differential Equations" (Cambridge U Press, 2007). Unfortunately, even the excellent style of this monograph is not sufficient to attract the attention of the physics community to this type of problems. This book is the first serious attempt to change the existing status quo. In it we demonstrate that, in fact, all branches of theoretical physics can be rewritten in the language of contact geometry and topology: from mechanics, thermodynamics and electrodynamics to optics, gauge fields and gravity; from physics of liquid crystals to quantum mechanics and quantum computers, etc. The book is written in the style of famous Landau-Lifshitz (L-L) multivolume course in theoretical physics. This means that its readers are expected to have solid background in theoretical physics (at least at the level of the L-L course). No prior knowledge of specialized mathematics is required. All needed new mathematics is given in the context of discussed physical problems. As in the L-L course some problems/exercises are formulated along the way and, again as in the L-L course, these are always supplemented by either solutions or by hints (with exact references). Unlike the L-L course, though, some definitions, theorems, and remarks are also presented. This is done with the purpose of stimulating the interest of our readers in deeper study of subject matters discussed in the text.Sample Chapter(s)Chapter 1: Motivation and Background (116 KB)Contents:Motivation and BackgroundFrom Ideal Magnetohydrodynamics to String and Knot TheoryAll About and Around Woltjer's TheoremTopologically Massive Gauge Theories and Force-Free FieldsContact Geometry and PhysicsSub-Riemannian Geometry, Heisenberg Manifolds and Quantum Mechanics of Landau LevelsAbrikosov Lattices, TGB Phases in Liquid Crystals and Heisenberg GroupSub-Riemannian Geometry, Spin Dynamics and Quantum-Classical Optimal ControlFrom Contact Geometry to Contact TopologyClosing Remarks:The Unreasonable Effectivenessof Contact Geometry and Topology in Physical SciencesAppendices:Heisenberg Group in the Context of Sub-Riemannian Geometry and Optimal ControlSub-Riemannian Dynamics of Josephson JunctionsQuantum Computers and Quantum Random WalksThe Measurement Protocol. Geometry and Topology of EntanglementsReadership: Researchers and professionals in applied mathematics and theoretical physics.
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