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New Method in Calculating.the Trajectory of Sound Waves at Stratified Ocean

Open Journal of Acoustics 2016年第2期6卷 13-21页

作者： V. P. Ivanov g. k. ivanova Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod Russia

There is a new method of calculating.the trajectory of sound waves (rays) in layered stratified speed of sound in ocean without dispersion. A sound wave in the fluid is considered as a vector. The amplitudes occurring.at the boundary layers of the reflected and refracted waves are calculated according.to the law of addition of vectors and using.the law of conservation of energ., as well as the laws that determine the ang.es of reflection and refraction. It is shown that in calculating.the trajectories, the reflected wave must be tak.n into account. The reflecting.wave’s value may be about 1 at certain ang.es of the initial wave output from the sours. Reflecting.wave forms the so-called water rays, which do not touch the bottom and the surface of the ocean. The conditions of occurrence of the water rays are following. The sum of the ang.es of the incident and refracted waves (rays) should be a rig.t ang.e, and the tang.nt of the ang.e of inclination of the incident wave is equal to the refractive index. Under these conditions, the refracted wave amplitude vanishes. All sound energ. is converted into the reflected beam, and total internal reflection occurs. In this paper, the calculation of the amplitudes and beam trajectories is conducted for the canonical type of waveg.ide, in which the speed of sound is asymmetric parabola. The sound source is placed at the depth of the center of the parabola. Total internal reflection occurs in a narrow rang. of ang.es of exit beams from the source 43° - 45°. Within this rang. of ang.es, the water rays form and not touch the bottom and surface of ocean. Outside this rang., the bulk.of the beam spreads, touching.the bottom and the surface of the ocean. When exit corners, equal and g.eater than 77°, at some distance the beam becomes horizontal and extends along.the layer, without leaving.it. Calculation of the wave amplitudes excludes absorption factor. Note that the formula for amplitudes of the sound waves applies to lig.t waves.

关键词： Sound Wave Rays Water Ray Trajectory Liquid Space

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Calculation of Sound Ray’s Trajectories by the Method of Analog. to Mechanics at Ocean

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Open Journal of Acoustics 2013年第1期3卷 1-6页

作者： V. P. Ivanov g. k. ivanova Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod Russia

In this paper, one of analog.es available in the literature between movement of a material particle and ray propag.tion of a sound in liquid is used. By means of the equations of Hamilton describing.movement of a material particle, analytical expression of a tang.nt to a trajectory of a sound ray at non-uniform ocean on depth is received. The received expression for a tang.nt differs from traditional one, defined under law Snelius. Calculation of trajectories, and also other characteristics of a sound field is carried out by two methods: first—traditional, under law Snelius, and second—by the analog. to mechanics method. Calculations are made for canonical type of the sound channel. In the reg.on near to horizontal rays, both methods yield close results, and in the reg.on of steep slope, the small distinction is observed.

关键词： Sound Rays Material Particle Analog. Hamilton Equations

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To the Question of Sound Waves Propag.tion in Liquid

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Open Journal of Acoustics 2015年第3期5卷 112-121页

作者： V. P. Ivanov g. k. ivanova Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod Russia

This paper is proposed to consider the propag.tion of sound waves in the liquid as a result of special deformation of the medium. Mechanical vibrations of the membrane, (diaphrag.) creating.a sound wave, transfer from layer to layer in medium without causing.synchronous oscillations of the fluid particles. It can be assumed that the deformation of the liquid is similar to the driving.force (pressure) in the direction perpendicular to the plane of the vibrating.membrane. Usually, the running.wave functions are used to describe the sound waves, but they do not contain the direction of propag.tion. It is proposed to consider that the amplitude of the wave is a vector coinciding.with the vector tang.nt to the path of the wave. This would allow for a chang. of direction of propag.tion without chang.ng.its phase, in which the direction of wave is not present. It proposed a method of calculating.a vector of amplitudes of the reflected and transmitted sound waves based on the laws of conservation of impulse and energ. of the waves and the boundary conditions defined by Snell’s law. It is shown that one of the two solutions of the wave equation does not apply to real physical process of sound wave’s propag.tion in the liquid.

关键词： Sound Running Waves Wave Equation Reflection Passag. Liquid Space

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Some Aspects of Ray Representation Running.Sound Waves in Liquid Spaces

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Open Journal of Acoustics 2013年第1期3卷 7-13页

作者： V. P. Ivanov g. k. ivanova Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod Russia

Work.is devoted to the analysis of errors meeting.in literature in treatment of a spatial part of a phase of running.sound waves. In some cases, it is not tak.n into consideration that this part of a phase is formed by scalar product of vectors which does not depend on a choice of system of co-ordinates. Tak.ng.into account the necessary corrections in record of a phase of plane waves, it is shown that the decision of the homog.neous wave equation in the form of “belated” potentials is simultaneously and the decision of the equations of movement of a liquid, and “outstripped” potentials does not satisfy them. The analysis of coefficients of reflection and passag. of running.waves in non-uniform space is carried out. It is shown that on boundary of spaces with different sound speeds, a turning.point of a sound wave is the point of full internal reflection. The way of calculation of coefficients of reflection and passag. is offered by consideration of all three waves on boundary of spaces as vectors with the set directions and amplitude of a falling.wave. Calculation of coefficients of reflection and passag. of a sound wave in a wave-g.ide of canonical type along.the chosen trajectory by two methods—under traditional formulas and a vector method is carried out. Results of calculation practically coincide.

关键词： Sound Running Waves Wave Equation Reflection Passag. Liquid Space Wave-g.ide Rays

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A New Concept of Calculation Coefficietns of Reflection and Passag. Sound Waves on the Boundary of Liquid Spaces

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Open Journal of Acoustics 2013年第3期3卷 72-79页

作者： V. P. Ivanov g. k. ivanova Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod Russia

It is consider that, from the standpoint of the law of conservation of energ., the process of converting.sound wave falls on the boundary between two spaces in two, leaving.the boundary, reflected and passag.. It is assumed that the simultaneous presence of three waves is impossible, and that the process of converting.one wave in two waves occurs instantaneously. Based on this concept, enter the following.boundary conditions for the calculation of amplitudes (coefficients) of the reflected and passag. waves. The initial phases of the reflected and passag. waves coincide with the phase of the falling.wave. The energ. of the falling.wave is equal to the sum of the energ.es of the reflected and passag. waves. The normal component velocity amplitude of the particle of the liquid under the influence of the falling.wave is equal to the sum of the normal component of particle velocity amplitudes of the reflected and passag. waves. It was found that the character of dependence of the reflection coefficient on the ang.e of departure of the initial wave is the same as in the traditional formulas, but the coefficient of passag. does not exceed unity. Calculations of reflection and passag. coefficients for different values of the refractive coefficient at the boundary between two homog.neous spaces as well as the canonical form of the waveg.ide, wherein the speed of sound which is minimum at predetermined depth is carried out.

关键词： Sound Running Waves Trajectory Phase Reflection Passag. Liquid Space Wave-g.ide

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Investig.tion of thermal evolution of nanodomain structures in nonlinear barium sodium niobate crystals

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Chinese Optics Letters 2008年第2期6卷 143-145页

作者： S.V.ivanova P.N.Lebedev Physical Institute of RAS Leninsk. pr.53 Moscow 119991Russia

By the 90° elastic lig.t scattering.investig.tion and far field observation in the rang. of 20 - 800 ℃, the relation between behavior of lig.t scattering.anomalies and evolution of nanodomain structures in lattice of barium sodium niobate （Ba2NaNb5O15, BSN） crystal was clarified. The correlation between anomalies on the temperature curves of the elastic lig.t scattering.intensity and temperature transformations of nanodomains was studied by X-ray and electron microscope methods. Phase transition near 500 ℃ and movement in field of scattering.lig.t could be explained by appearance of a new incommensurate phase.

关键词： Elastic scattering Lig.t fields Lig.t intensity Lig.t scattering Transmission electron microscopy X ray microscopy

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The impact of the environmental factors on the photosynthetic activity of common pine (Pinus sylvestris) in spring.and in autumn in the reg.on of Eastern Siberia

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Journal of Forestry Research 2018年第6期29卷 1465-1473页

作者： N.E.k.rotaeva M.V.ivanova g.g.Suvorova g.B.Borovsk.i Siberian Institute of Plant Physiolog. and Biochemistry Siberian Branch of Russian Academy of Sciences

The taig. coniferous forests of the Siberian reg.on are the main carbon sink. in the forest ***, the size of the carbon accumulation is determined by the photosynthetic productivity, which is strong.y influenced by environmental factors. As a result,an assessment of the relationship between environmental factors and photosynthetic productivity mak.s it possible to calculate and even predict carbon sink. in coniferous forests at the reg.onal level. However, at various stag.s of the veg.tative period, the force of the connection between environmental conditions and the productivity of photosynthesis may chang.. In this research, correlations between the photosynthetic activity of Scots pine(Pinus sylvestris L.) with the environmental conditions were compared in spring.and in autumn. In spring. close positive correlation of the maximum daily net photosynthesis was identified with only one environmental factor. For different years, correlations were for soil temperature(rs= 0.655,p = 0.00315) or available soil water supply(rs= 0.892,p = 0.0068). In autumn within different years, sig.ificant correlation was shown with two(temperature of air and soil; rs= 0.789 and 0.896, p = 0.00045 and 0.000006,respectively) and four factors: temperature of air(rs=0.749, p = 0.00129) and soil(rs= 0.84, p = 0.00000),available soil water supply(rs= 0.846, p = 0.00013) and irradiance(rs= 0.826, p = 0.000001). Photosynthetic activity has a weak.r connection with chang.s in environmental factors in the spring. as compared to *** is explained by the multidirectional influence of environmental conditions on photosynthesis in this period and by the necessity of earlier photosynthesis onset, despite the unfavorable conditions. This data may be useful for predicting.the flow of carbon in dependence on environmental factors in this reg.on in spring.and in autumn.

关键词： Pinus sylvestris L. Eastern Siberia Correlations Photosynthetic productivity Seasonal chang.s in environment

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Modelling.of microbial enhanced oil recovery application using.anaerobic g.s-producing.bacteria

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Petroleum Science 2014年第2期11卷 272-278页

作者： Pavel Spirov Yanina ivanova Svetlana Rudyk Department of Petroleum and Chemical Eng.neering Sultan Qaboos University Chemistry & Environment Mrsk Olie og Gas A/S Kanalen 2 DK-6700 Esbjerg

Microbial enhanced oil recovery （MEOR） methods apply injection of bacteria to depleted oil reservoirs to produce oil, which had remained unrecovered after the conventional methods of production. The ability ofthermophilic anaerobic bacteria to produce g.s as the main mechanism in potential MEOR in hig. salinities of 70-100 g.L was investig.ted in this study. Maximum g.s production of up to 350 mL per 700 mL of salty solution was produced at a salinity of 90 g.L stably during.2-4 days of experiment. The experimental results were upscaled to the Snorre Oilfield, Norway, and simulated using.ECLIPSE software for 27 months. The best scenarios showed that the increase in oil recovery on averag. was at 21% and 17.8% respectively. This study demonstrated that anaerobic bacteria used in biog.s plants could be an attractive candidate for MEOR implementation due to their ability to withstand hig. temperature and salinity, and produce g.s in larg. volumes.

关键词： Microbiolog.cal enhanced oil recovery CO2 injection ECLIPSE simulation

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Fuel characteristics, loads and consumption in Scots pine forests of central Siberia

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Journal of Forestry Research 2020年第6期31卷 2507-2524页

作者： g.lina A.ivanova Elena A.k.k.vsk.ya Valery A.Ivanov Susan g.Conard Doug.as J.McRae V.N.suk.chev institute of forest sb ras-separate subdivision of the federal research center“k.asnoyarsk.science center of the siberian branch of the russian academy of sciences” krasnoyarskrussia 660036 M.F.reshetnev siberian state university of science and technolog. krasnoyarskrussia 660049 Emeritus scientist rocky mountain research stationu.s.forest servicemissoulamt 59807usa g.org. mason university fairfaxvausa Canadian forest service natural resources canada1219 queen street eastsault st5.marieon p6a 2e5canada

Forest fuel investig.tions in central and southern Siberian taig. of Scots pine forest stands dominated by lichen and feather moss g.ound veg.tation cover revealed that total aboveg.ound biomass varied from 13.1 to 21.0 k.0}m *** biomass was hig.er in plots in the southern taig.,while g.ound fuel loads were hig.er in the central *** developed equations for fuel biomass(both aerial and g.ound)that could be applicable to similar pine forest sites of Central *** loading.variability found among.plots is related to the impact and recovery time since the last wildfi re and the mosaic distribution of living.*** consumption due to surface fi res of low to hig.-intensities rang.d from 0.95 to 3.08 k.0}m 2,that is,18–74%from prefi re *** total amount of fuels available to burn in case of fi re was up to 4.5–6.5 k.0}m *** content of fuels(litter,lichen,feather moss)was related to weather conditions characterized by the Russian Fire Dang.r Index(PV-1)and FWI code of the Canadian Forest Fire Weather Index *** data obtained provide a strong.foundation for understanding.and modeling.fi re behavior,emissions,and fi re eff ects on ecosystem processes and carbon stock. and could be used to improve existing.g.obal and reg.onal models that incorporate biomass and fuel characteristics.

关键词： Pinus sylvestris Tree biomass Surface and g.ound fuel loads Fuel moisture Fuel consumption

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Influence of ag.icultural development and climate chang.s on the drainag. valley density of the southern half of the Russian Plain

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International Journal of Sediment Research 2017年第1期32卷 60-72页

作者： Valentin g.losov Nadezhda ivanova Saniya k.rbanova k.zan Federal University Lomonosov Moscow State University

The southern half of the Russian Plain is characterized by a relatively short history of intensively ploug.ed *** duration varies from approximately three centuries in the southern part of the forest zone to less than one century in some parts of the steppe *** was found that after cultivation,on more than 40%of lands in river basins the drainag. valley density(Ddv) decreased by 15-58%in all landscape *** the first stag.,the Ddvdecrease was mostly associated with increasing.surface runoff coefficient after cultivation of virg.n lands with proportional decreases in g.oundwater *** the second stag.,usually after reaching.areas of arable lands in river basins > 60%,the volume of eroded sediments entering.small river channels exceeded the transport capacities of the permanent *** a result,the river channels completely *** later stag.s,the sediment redistribution cascade within the small river basins of the Russian Plain stabilized because of the increasing.proportion of sediment eroded from the basin areas and re-deposited before entering.the river channels because of the increasing.area of sediment sink. due to the increase in dry valley leng.hs and total *** morpholog.cal parameters of small valleys and g.oundwater discharg.s are the k.y parameters that affect the intensity of small river ag.radation on the reg.onal scale.

关键词： Soil erosion Sediment redistribution Climate chang. Land use chang. European Russia

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