Application Of Optical Methods Research Articles

Preface

The conference “Optical Methods of Flow Investigation” (OMFI) has been regularly held since 1989 at intervals of 2 years. The All-Union Seminar was held in 1989, I and II All-Union Conferences (founder – Institute of Thermal Physics of the Siberian Branch of the Russian Academy of Sciences) was held in 1991 and 1993. Since 1995, conferences have been held at the Moscow Power Engineering Institute (MPEI) under the auspices of the Siberian Branch of the Russian Academy of Sciences and the Ministry of Education of the Russian Federation, the co-founders were MPEI and the Institute of Thermophysics of the Siberian Branch of the Russian Academy of Sciences. Since 2019 Scientific and Technological Center of Unique Instrumentation of the Russian Academy of Sciences has also become a co-organizer of the conference.This issue of the Journal is devoted to research and studies presented at the XVI International Scientific and Technical Conference “Optical Methods of Flow Investigation” (OMFI-2021). The conference was held in Moscow Power Engineering Institute, Moscow, Russia, on 28 June – 02 July 2021. The National Research University “Moscow Power Engineering Institute” is one of the leading technical universities in Russia having about 15,000 students from more than 60 countries. MPEI is one of the largest technical universities in Russia. It provides the specialist’s training and scientific research in the field of energy, electrical engineering, radio electronics, computer engineering.The conference brought together experts from different organizations to initiate discussions on topics that are of interest to the conference attendees. The conference papers presented in the following areas: laser anemometry, flow visualization, development of quantum-optical devices, computer methods of signal and image processing, laser and optical interferometry, application of optical methods, acousto-optics and optoacoustic, optical methods in biomedicine and ecology, also included papers of the Youth workshop «Modern Methods of Flow Investigation – 2021».List of Organizing and program committees of the conference are available in this pdf.

Применение оптических методов в исследовании течения газа в системе газообмена двигателя внутреннего сгорания

Применение оптических методов в исследовании течения газа в системе газообмена двигателя внутреннего сгорания

Transversally travelling ultrasound for light guiding deep into scattering media

The application of optical methods for tissue diagnosis, activation, and treatment suffers dramatically from the low accessible depths due to strong light scattering in tissues. Here we demonstrate a method to address this issue by utilizing transient ultrasound waves, travelling transversally to the light propagation direction, to guide light into deeper tissue regions. We study the formation of the ultrasound-induced refractive index structures and waveguides using simple ultrasound field configurations and analyze their effects on the propagation of short light pulses. As a proof of concept, we demonstrate using 5 ns pulses of 532 nm light and Intralipid-20%-based phantoms with mu _{mathrm{s}}^prime up to 4.5 cm−1 a waveguide supported light intensity increase up to the depths of at least 90 mean free paths.

Application of optical methods in tests of new materials with gradient structure

The main idea of the article is to demonstrate the possibility of applying the laser dynamic speckle interferometry technique to control the processes of fatigue failure of specimens with a gradient structure. A distinctive feature of the described technique is the possibility of practical application on high-frequency machines as an experimental non-contact method for recording surface changes in the studying objects with a complex structure. Besides, the proposed technique can be used as an indicator characterizing irreversible processes during fatigue failure and for analyzing the fatigue crack growth kinetics.

The application of optical methods for the assessment of the aesthetic compatibility of architectural concrete

Architectural concrete is usually defined as concrete for with the requirements regarding aesthetics of its surface are formulated. The currently applied requirements regarding aesthetics compatibility are mostly based on subjective methods of concrete surface assessment. While it is relatively easy to apply quantitative criteria for components of surface analysis such as porosity, the quantitative assessment of colour compatibility could be problematic. In this paper, an optical method for the assessment of concrete surface colour is presented. The main goal of the investigation was to assess the effect of modifications of the aggregate used for preparation of architectural concrete mix on the surface colour. Optical test methods using a self-made DARK-BOX device were used. The obtained results confirmed the usefulness of the method used to assess the colour compatibility of architectural concrete surfaces.

Preface

The conference “Optical Methods of Flow Investigation” (OMFI) has been regularly held since 1989 at intervals of 2 years. The All-Union Seminar was held in 1989, I and II All-Union Conferences (founder – Institute of Thermal Physics of the Siberian Branch of the Russian Academy of Sciences) were held in 1991 and 1993. Since 1995, conferences have been held at the Moscow Power Engineering Institute (MPEI) under the auspices of the Siberian Branch of the Russian Academy of Sciences and the Ministry of Education of the Russian Federation, the co-founders were MPEI and the Institute of Thermophysics of the Siberian Branch of the Russian Academy of Sciences. Since 2019 Scientific and Technological Center of Unique Instrumentation of the Russian Academy of Sciences has also become a co-organizer of the conference.This issue of the Journal is devoted to research and studies presented at the XV International Scientific and Technical Conference “Optical Methods of Flow Investigation” (OMFI-2019). The conference was held in Moscow Power Engineering Institute, Moscow, Russia, on 24–28 June 2019. The National Research University “Moscow Power Engineering Institute” is one of the leading technical universities in Russia having about 15,000 students from more than 60 countries. MPEI is one of the largest technical universities of Russia. It provides the specialist’s training and scientific research in the field of energetic, electrical engineering, radio electronics, computer engineering.The conference brought together experts from different organizations that had a great opportunity to share knowledge during oral and poster presentations, to initiate discussions on topics that are of interest to the conference attendees. The conference papers presented in the following areas: laser anemometry, flow visualization, development of quantum-optical devices, computer methods of signal and image processing, laser and optical interferometry, application of optical methods, acousto-optic and optoacoustics, optical methods in biomedicine and ecology, also included papers of the Youth workshop «Modern methods of flow investigation – 2019».

WITHDRAWN: Application of optical methods to determine the stability of emulsions containing carotenoids

Abstract Colloidal systems such as emulsions are commonly used to improve aesthetics but they may also be applied to deliver active ingredients. Recently, group of pigments known as carotenoids, have been added to emulsions as active compounds mainly due to their antioxidant properties. The stability of these formulations is a critical parameter for both pharmaceutical and cosmetics industries. Therefore, in this study optical methods such as multiple light scattering and laser diffraction were applied to determine the stability of various emulsions containing carotenoids such as β-carotene, lycopene and astaxanthin. The results of both methods proved that the type of carotenoid added did not influence the emulsions stability. The stability of emulsions depends mainly on the preparation methods and on the type of emulsifier applied.

Применение оптических методов для изучения теплостойкости композиционных материалов

Применение оптических методов для изучения теплостойкости композиционных материалов

Studies of cortical connectivity using optical circuit mapping methods.

An important consideration when probing the function of any neuron is to uncover the source of synaptic input onto the cell, its intrinsic physiology and efferent targets. Over the years, electrophysiological approaches have generated considerable insight into these properties in a variety of cortical neuronal subtypes and circuits. However, as researchers explore neuronal function in greater detail, they are increasingly turning to optical techniques to bridge the gap between local network interactions and behaviour. The application of optical methods has increased dramatically over the past decade, spurred on by the optogenetic revolution. In this review, we provide an account of recent innovations, providing researchers with a primer detailing circuit mapping strategies in the cerebral cortex. We will focus on technical aspects of performing neurotransmitter uncaging and channelrhodopsin-assisted circuit mapping, with the aim of identifying common pitfalls that can negatively influence the collection of reliable data.

Experimental study of submillimeter droplets dynamics and breakup in continuous supersonic flow terminated by shock wave

The present paper reports an application of optical methods, namely PIV, background-oriented-schlieren (BOS) and high-magnification imaging with background illumination to study of dynamics and breakup of 10-100 μm size droplets in continuous supersonic flow terminated by a normal shock wave. Flow diagnostics was performed by means of BOS and PIV. Shadow photography allowed to specify velocity ranges for different droplet sizes and to visualize droplets dynamics and breakup modes. Features of the experimental setup and certain details of implemented measurement system are considered. Results of velocity measurements and droplets behavior, including deformation and breakup, are presented and analysis of experimental conditions and dimensionless parameters affecting the droplets behavior is performed. Distinctive features of deformation and breakup processes of submillimeter scale droplets are revealed.

Erratum: Substrate influence on the plasmonic response of clusters of spherical nanoparticles [Phys. Rev. B83, 075426 (2011)

The reflection and scattering of light from surfaces is a topic that has been much discussed in the scientific literature. The application of optical methods for the characterization of surfaces and the understanding of natural phenomena is dependent on good models for the optical properties of surfaces and interfaces. In this work, we will examine three different aspects of the optical properties of surfaces and interfaces.The measurement of polarization effects of surfaces is dependent on wellperforming Mueller matrix ellipsometers. While designing Mueller matrix ellipsometers for a single wavelength is trivial, the design of broad-band imaging ellipsometers is a much more challenging problem. We discuss the use of genetic algorithms to optimize such ellipsometers in a very general fashion, and apply them to ellipsometers based on various liquid crystal technologies. The results include an ellipsometer design which was patented, and which outperforms previous designs both in terms of spectral bandwidth and noise propagation.Recent progress in the ability to manipulate matter on the nanoscale has led to great interest in the biological, chemical, and physical properties of nanoparticles and nano-sized structures. Depositing nanoparticles on top of a surface modifies the optical properties of both the particles as well as the substrate: any optical resonances that the particle(s) possess are modified by the substrate, and the reflectivity of the substrate is changed due to the presence of the particles. The electromagnetic interactions between nanoparticles and substrate are here investigated in the quasistatic regime, with discussion of both small clusters of nanoparticles as well as (infinite) periodic lattices of nanoparticles deposited on a substrate. The results include analysis of the interactions and resonances found in nanoparticle clusters deposited on a substrate.When light is incident on surfaces possessing random roughness or structure, the light is scattered according to the statistical properties of the surface. While there has been significant progress on surface scattering from surfaces with one-dimensional surface profile functions, less attention has been devoted to numerical models of surfaces possessing two-dimensional surface profiles. The main reason for this is that the solution of these models requires a large amount of computational power, even by today’s standards. We attempt to shed some light on optical effects observed in scattering from two-dimensional rough surfaces, with some focus on polarization effects, which are absent in scattering from one-dimensional surfaces. The Mueller matrix for a rough surface is also calculated, and describes the full polarization effects of rough surface scattering.

Some optical methods for modal analysis of musical instruments.

Because of their high spatial resolution, optical methods have become important for modal analysis of vibrations in musical instruments. Among optical methods for modal analysis are time-average holographic interferometry, pulsed TV holography, disital speckle interferometry, and scanning vibrometry. We review briefly principles and applications of optical methods for modal analysis.

Berechnung und experimentelle Prüfung einer Implantatstruktur in Faserverbundbauweise für die Überbrückung von Kontinuitätsdefekten des Unterkiefers / Computation and experimental examination of an implant structure made by a fibre-reinforced building method for the bypass of continuity defects of the mandible

A partial resection of the lower jaw often has to be carried out in the context of the surgical removal of tumours in the lower jaw, mouth and tongue-floor space and lower jaw fractures with loss of substance, benign bone lesions and extensive difficult inflammation of bone tissue, respectively. The primary reconstruction of the lower jaw after partial resection with loss of continuity is mainly important for functional and aesthetic reasons. The defects of lower jaw continuity are often bridged with metal plates to reconstruct the masticatory function of the lower jaw, temporarily or permanently. Functional as well as aesthetic disadvantages arise in the case of the application of such plates as a result of a high stiffness jump between reconstruction plate and bone and their insufficiently individual design. The employment of biocompatible, carbon-fibre-reinforced Polyetheretherketon (CF-PEEK) permits the development of a geometry- and stiffness-adapted carrying structure for the mandible. For the demand-adapted dimensioning and the test of a CF-PEEK bandage, the application of optical methods, such as the grey value correlation method, is suited as well as numeric methods, such as the finite element method. In an initial analysis of deformation behaviour, the various osteosynthesis configurations are comparatively investigated on a model jaw. The calculations and tests of the lower jaw model show that the use of the new CF-PEEK bandage compared to the use of conventional titanium osteosynthesis plates shows a mechanical behaviour which is much better adapted to the natural lower jaw.

Application of Optical Methods in Nuclear Track Measurements

Application of Optical Methods in Nuclear Track Measurements

Real-time determination of fringe pattern frequencies: An application to pressure measurement

Retrieving information in real time from fringe patterns is a topic of a great deal of interest in scientific and engineering applications of optical methods. This paper presents a method for fringe frequency determination based on the capability of neural networks to recognize signals that are similar but not identical to signals used to train the neural network. Sampled patterns are generated by calibration and stored in memory. Incoming patterns are analyzed by a back-propagation neural network at the speed of the recording device, a CCD camera. This method of information retrieval is utilized to measure pressures on a boundary layer flow. The sensor combines optics and electronics to analyze dynamic pressure distributions and to feed information to a control system that is capable to preserve the stability of the flow.

On the determination of eigenfrequencies for nanometer-size objects

At present, the problem of the experimental determination of mechanical characteristics for nanometersize objects (nanoobjects) is urgent. One of the most efficient methods for the determination of elastic-moduli is based on the measurement of the eigenfrequencies of objects under study. However, the measurement of nanoobject frequencies, in particular, on the basis of optical methods turns out to be problematic [1]. The main, though not exclusive, limitation upon the application of optical methods is the fact that the laser-beam cross section is not a point ...

Mechanical characterization of membrane like microelectronic components

The tools of optical measurement of deformation are increasingly used to characterize both the mechanical and the thermal properties of MEMS components and especially membranes. In the paper the application of optical methods for membranes tension measurement, their thickness variations and vibrational mode shapes identification of membrane like microcomponents is reported. Using of several sophisticated optical techniques is reviewed such as autocollimation observation of the radii of curvature of deflected 6-in. large membranes, Fizeau interferometry of membrane thickness, Laser doppler vibrometry for membrane vibration movement and deformation propagation and also time-average recording of vibrational mode structure. Specific features of the methods, their performances and limitations regarding practical experience of the exploitation are reported, too.

Silicon Microchannel Array as a Basis of Biosensor Device

AbstractThis work shows the possibilities of using the silicon-based microchannel array (Si-MCA) as a 3D-solid support of DNA probes and studying of application of optical methods for DNA hybridization direct analysis. It was obtained that amount of immobilized oligodeoxyribonucleotides on the Si-MCA surface is enhanced with lighting of Si-MCA microchannel. The sample of 160 μm thickness succeeded in immobilizing oligonucleotides 40 times as much as the standard glass slides having the same external surface. The application of Si-MCA as a carrier of DNA allows doing direct analysis of nucleic acids in infrared region by the FTIR method that essentially simplifies creation of a biosensor based on the Si-MCA. It is indicated that using of the Si-MCA as a diffraction grating in visible and UV spectra allows simplifying the spectral analysis of biochemical reaction. It was success confidently to distinguish the mediums differing on the refractive index by dn=0.006.

Reply to “Remarks on the electrochemical application of optical methods for the determination of stress in electrodes by T.A. Rokob, G.G. Láng”, Electrochim. Acta 51 (2005) 93–97

Reply to “Remarks on the electrochemical application of optical methods for the determination of stress in electrodes by T.A. Rokob, G.G. Láng”, Electrochim. Acta 51 (2005) 93–97

Optische Konzentrations‐ und Temperatur‐Messung in Aerosolen und Sprays

AbstractOptical measurement of concentration and temperature in aerosols and sprays. This article surveyes progress in the development and application of optical methods, particullarly in Raman scattering and fluorescence for the analysis of aerosols and sprays. The main emphasis lies on examination of the particle phase. Fundamentals and state of the art in the determination of molecular composition of the particle phase with the aid of linear and simulated Raman scattering are described and the role of structural resonance discussed. Various models are presented for distinguishing between the contribution of the liquid and the gas phase to Raman scattering and fluorescence. Finally, new developments pertaining to the measurement of droplet temperature in aerosols and sprays are described.