bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measurement of high-speed gas-droplet flow characteristics by pulse photography method
Authors: Bokuchava N I , Inochkin F M 
Published: December 2019

Abstract
The subject of this work is the optical probe measurement system for the measure of droplets parameters in high-speed two-phase flow. A system with dark-field illumination including two pulse lasers as illumination sources is used for droplets registration. Rays from lasers intersect at the angle of 120˚ and form a measurement volume. When a droplet crosses the volume, it refracts a part of the light. Refracted rays pass through the optical system and create two highlights on the sensor. Distance between two highlights is equal to the droplet diameter. System for measurement of coarse droplets parameters in wet steam flow, based on the described method, is developed. Main components of the system are the optical probe and PC with software. The system allows determining the following parameters of droplets: size distribution (20–600 µM), velocity distribution (0.1–300 m/s), movement direction. The results of measurements of the system in two-phase flow are presented in this work. The system is successfully operated as part of the complex for investigation of two-phase flow parameters on the model turbine.
LED illumination module for fluorescence and spectroscopic studies in microscopy
Authors: Batshev V I , Blokhin A A , Belov A S 
Published: December 2019

Abstract
In this report we produce a microscopic illuminator consisting of four light emitting diodes (LEDs) with different wavelength. The radiation power of each LED could be controlled independently. The dichroic mirrors are used as a beam combiner. So, it is possible to create a highlight of the required spectral composition on the object under study. This illuminator is useful both for fluorescent analysis or spectral imaging.
Calculation of the optical variosystems with tunable optical power lenses
Authors: Nosov P A , Piskunov D E , Vinogradov M A , Tigaev V O , Yablokova A A 
Published: December 2019

Abstract
Modern optical variosystems include lenses with a fixed and tunable focal length, which can also move relative to each other according to a certain law. The method of dimensional synthesis of the variosystems converting incoherent radiation and laser Gaussian beams is considered. Examples of the calculation of optical variosystems are presented.
Photothermocapillary detection of conductive track ruptures on a printed circuit board coated with a protective film
Authors: Zykov A Yu , Ivanova N A 
Published: December 2019

Abstract
The photothermocapillary (PTC) method has been proposed to detect ruptures of the copper tracks of a printed circuit board coated with a black protective film absorbing the pump laser radiation. The ruptures were simulated by obtaining parallel tracks of different lengths by etching in ferric chloride solution. The method consisted of the scanning with the pump laser of the tracks along a line perpendicular to them and passing through their midpoints, and plotting a scan-profile of the diameter of PTC signal as a function of the scan coordinate. The scan-profile was a sequence of maxima and minima the diameters of the PTC signal corresponded to the beam position in the middle between adjacent tracks and in the midpoint of the track, respectively. It was found that with an increase in the track length above a critical value, dependent on the laser beam power, the diameter of PTC signal reaches saturation. With increasing power by 1.85 times, the sensitivity of the PTC method increases by 2.57 times. The spatial resolution of the PTC method reaches tens of micrometers. Experimental results have shown that the proposed PTC method is simple and efficient for detecting of hidden defects of the copper tracks on the PCB.
Effect of the nanoparticle composition on the fluorescence of carbon nitride coatings
Authors: Bogomolov A B , Zinin P V , Kulakov S A , Kutvitsky V A , Bulatov M F , Kutuza I B 
Published: December 2019

Abstract
In this report we present results on synthesis of graphitic carbon nitride (g-C3N4) coating on various nanoparticles. Carbon nitride coatings were grown on of SiO2, TiO2, and Fe2O3 nanoparticles by the decomposition of the melamine at 300 °C. Relative fluorescence quantum yield was determined by comparing the fluorescence intensity of coated nanoparticles with that of the fluorescein in NaOH solution excited a green laser (532 nm). It was demonstrated that the g-C3N4 coated TiO2 nanoparticles have the highest quantum yield of the fluorescence among investigated nanoparticles.
Hyperspectral camera application for remote gas analysis
Authors: Neverov S M 
Published: December 2019

Abstract
The report reviewed current systems for monitoring gas leaks at industrial facilities. Since in industrial plants the emission of some gases can be technologically justified, and the presence of others indicates a violation of the technological process and is a sign of an emergency situation, a possible option is described not only for detection the fact of leakage, but also for the classification of detected gases. We considered existing hardware-software complexes including acousto-optical, and listed their shortcomings, such as insufficient sensitivity and low data processing speed. In general, we describe the novel technical implementation of imaging spectrometry. For simultaneous detection of spatial and spectral properties of objects, the infrared sensor is divided into a mosaic of the smallest optical filters. Each filter passes individual intervals of the spectrum, blocking the others. The uncooled detector 640×512 can be covered with 16 filters, which spectral characteristics should correlate with the absorption spectra of target gases.
Research of the dynamics of two-phase flows by optical methods PIV/IPI
Authors: Guryanov A I , Veretennikov S V , Evdokimov O A , Guryanova M M , Kalinina K L 
Published: December 2019

Abstract
The paper describes conditions and experimental results of the dynamics of two-phase flows research by optical methods PIV/IPI. Studies were carried out for the finely dispersed flow generated by the centrifugal atomizer. Such atomizer is necessary for the implementation of certification of aircraft engine critical mode under rain conditions: height of 6100 m, the Mach number M = 0.8. The flow parameters were measured for 9 modes of liquid pressure in the nozzle from 0.2 to 1.0 MPa in increments of 0.1 MPa. Velocity vectors obtained for these pressure modes shown that maximum velocity of the droplets is achieved nearby the nozzle section and ranges from 20 to 30 m/s. Increasing the pressure reduces the difference between velocities at peripheral and axial regions of the flow.
Study of effects of electromagnetic factors on the early development of biological organisms using comprehensive multispectral optical and scanning acoustic microscopy approach
Authors: Burlakov A B , Khokhlov D D , Domanskiy V L , Titov S A 
Published: December 2019

Abstract
The effects of electromagnetic field on development of biological organisms were studied in this work by multispectral optical microscopy and scanning acoustic microscopy. The living embryos of loach Misgurnus fossilis at early stages of development were used as biological objects. The electric field applied to the living organism was generated by a specially designed unit that can operate independently or in combination with the acoustic microscope. It was shown that the sequentially recorded multispectral optical and acoustical images reveal dynamics of the development. The long lasting experiments confirm minor effect of the optical and acoustic radiation on the embryos. The scanning acoustic microscope was used for in vivo visualization of three dimensional structure of the egg, estimation of the acoustical properties of the yolk tissue and visualization of slow substance flows inside the object. The speed of motion depends on the location of the investigated area, status of the organism and its development stage. The estimated valued of the speed is in a range of 0.1 – 1 µm/s. It was shown that the application of the electric field causes deceleration of the embryos development.
Application of the structured laser illumination to planar optical diagnostics of the flows with nonuniform density
Authors: Sharaborin D , Tolstoguzov R , Frolova E 
Published: December 2019

Abstract
The aim of this work was to develop a method of panoramic optical diagnostics of the inhomogeneity of the density field in stratified flows based on the registration of the distribution of the Rayleigh scattering intensity using structured laser radiation. Several approaches have been implemented for organizing spatial modulation of laser illumination, intended for use with various values of the incident radiation energy density. To test the processing and reconstruction algorithms of the experimental data, a series of measurements was carried out using the method of planar laser-induced fluorescence. The distribution of local density in a jet of carbon dioxide flowing into atmospheric air was measured experimentally using a method based on the registration of Rayleigh scattering.
Detailed investigation of bag-breakup process in the context of spray of droplets generation within wind-wave interaction
Authors: Kandaurov A A , Sergeev D A , Troitskaya Yu I 
Published: December 2019

Abstract
The main mechanism responsible for the generation of spume droplets in marine atmospheric boundary layer was investigated at the experiments carried out at the high-speed wind-wave flume of IAP RAS. Strong wind tears off water from the crest of the waves during bag breakup fragmentation of small-scale disturbances that arise at the air-water interface. Separate bag-breakup event forced to occur in a dried high-speed wind-wave flume was investigated qualitatively and quantitatively using multiperspective shadowgraph high-speed video recording.
Multi-spectral phase imaging based on acousto-optic selection of light in common-path interferometer
Authors: Burmak L , Zykova L , Machikhin A , Chichigin B 
Published: December 2019

Abstract
Multispectral interference techniques are widely used in biomedicine and science for quantitative characterization of morphological, chemical and other properties. These techniques, for example, multispectral digital holography and spectral-domain optical coherence tomography, require wavelength tuning in the interferometer. In this paper, we discuss the effectiveness and potential applications of acousto-optic light filtration for this purpose. We show experimentally that acousto-optical tunable filters are effective for simultaneous spectral and phase data collection not only in conventional dual-path interferometers but also in a common-path interferometer. Scheme of a compact spectral interferometric module based on such interferometer is presented.
Spectral oil analyzer
Authors: Lashova A A , Korsakov V S , Korsakova E A , Kashuba I A , Zhukova L V 
Published: December 2019

Abstract
We worked out a spectral oil analyzer, implemented the method of Fourier transform infrared spectroscopy, which allow simultaneous detecting characteristic peaks of water absorption and sulfur-containing substances in oil within the wavelength range from 0.2 to 25.0 µm. The usage of fiber-optic delivering channels makes it possible to produce online industrial probes for the control of chemical composition and concentration, what is demanded at oil producing platforms and oil refinery plants. As identifiers, we used the most intense absorption peaks of water (λ – 1.45 µm, 1.95 µm, 3.00 µm, 6.00 µm), oil (λ – 1.72 µm, 2.31 µm, 3.41 µm) and sulfur-containing heterocycles (λ – 8.00 µm). The spectral analyzer consists of a broadband-light source, a flow-cell, a fiber-optic assembly, narrow-band optical filters and photodetectors. For delivering a broadband optical signal, a fiber-optic assembly was developed. It comprises silica fibers and polycrystalline fibers derived from solid solutions of silver and thallium (I) halides. It was calculated the effective area and diameter of each fiber type in the assembly, taking into account attenuation coefficients and overall optical losses of the system. Using eight channels for the probe at the same time, we were able to measure the content of water and sulfur-containing substances in oil in concentrations from 0.1 to 100.0 wt %.
Studies by PIV-methods of self oscillating hydrodynamic processes in the elements of pipeline
Authors: Sergeev D A , Kandaurov A A 
Published: December 2019

Abstract
Investigation of the self-oscillation regimes in the flow chamber modelling elements of stop valves in the pipeline in the systems of heat exchange in the power plants were performed by using PIV methods. Dependency of parameters of self-oscillation regimes on the parameter of the gap between the inlet and outlet pipe line in the chamber was investigated. Simultaneous measurements of the hydrodynamic and acoustic fluctuations allows us to offer explanation of the observed regimes.
Technical implementation of acousto-optical instruments: basic types
Authors: Pozhar V E , Bulatov M F , Machikhin A S , Shakhnov V A 
Published: December 2019

Abstract
The comparative analysis of the basic characteristics of acousto-optical instruments of different levels of integration and complexity: functional elements, devices and systems. The basic characteristics and their interrelations are determined. It is shown that each class requires individual approach to design. We indicate a novel trend of development of special class of instruments – modules, which are easy-to-integrate into existant devices or systems extending their functionality. The principle requirements for this kind of instruments are their connectivity with the device in each channel, port, protocol, so that the module adding and removing need not the device retuning or adjustment. This tendency has universal nature. The presented analysis is convinient for prognosing prospects and basic directions of acousto-optical instruments development.
Analysis of the statistical errors of the emissivity measurement of a laser heated surface by acousto-optical tunable filter
Authors: Mantrova Yu V , Zinin P V , Bykov A A , Bulatov K M 
Published: December 2019

Abstract
The aim of this report is to conduct a rigorous data analysis of the emissivity and temperature measurements on the surface of a solid specimen during laser heating (LH). Measurements of the emissivity and temperature is based on the use of a tundem acousto-optic filter (tandem acousto-optical tunable filter or TAOTF) connected with a high-resolution video camera. The set of spectral images obtained with the help of TOTF in the range of 750-800 nm makes it possible to calculate the dependence of the radiation intensity of the heated surface on the wavelength at each point of the surface. The distribution of the temperature and the emissivity of the heated body surface is obtained by fitting the experimental spectral dependence of the radiation intensity at each point of the heated object to the Planck distribution using the least squares method (LSM). A development of the mathematical analysis of the statistical errors of the emissivity determination by the LSM is described.
The specifics of single-mode laser modules application in optical-electronic complexes based on light scattering
Authors: Parshin V , Bliznyuk V , Evtikhieva O 
Published: December 2019

AbstractThe polarization state of edge-emitting single-mode laser modules radiation and their conditions of using in laser measuring systems of scattered radiation diagnosis are considered. For laser modules from two batches, both the polarization degree of collimated radiation and polarization degree spatial dependence in two orthogonal planes when there is no collimation are measured. It is established the angular dependence of non-collimated radiation polarization degree at different planes is various. We also considered the impact laser diodes degradation on these dependencies. It is shown that while exploitation of single-mode laser diodes in laser systems for scattered radiation characteristics researching it is needed to make control the polarization state of their radiation while service.
Application of a laser-Doppler anemometry for the study of unsteady flow structure in a model micro-hydro turbine
Authors: Shtork S I , Litvinov I V , Gorelikov E Yu , Mukhin D G , Dremov S V , Suslov D A 
Published: December 2019

Abstract
Current work deals with an LDA characterization of the velocity distributions and pressure pulsation maps in an axisymmetric draft tube for the flow conditions corresponding to wide range of the operating regimes of the micro-hydro turbine unit. For the detailed analysis of the velocity profiles, three characteristic regimes corresponding to part-load regime with precessing vortex core formation, best efficiency regime and overload regime of hydro turbine operation were selected. To capture spatial characteristics of the unsteady flow for part-load regime a phase averaging procedure for the LDA data has been employed.
Lasing in slurry-like active medium on LiF:F2 microparticles
Authors: Burdukova O A , Konyushkin V A , Petukhov V A , Senatsky Yu V , Zverev P G 
Published: December 2019

Abstract
Active media composed of the particles of solid-state laser-active material immersed in the liquid are the subject of research since this approach can provide new solutions to the problem of heat removal from the laser medium. Investigation of the active medium on microparticles of LiF crystal with F2 color centers is presented. The technique of the preparation and characterization of the index-matched slurry-like mixture was developed. Powders of LiF crystal particles with F2 color centers with size from 50 to 1000 μm immersed in various liquids and their mixtures were tested. Laser radiation of a compact cavity containing two flat dichroic mirrors and a glass cuvette with the LiF:F2 slurry with grain size of 500 ÷ 1000 μm and the mixture of heptane and vaseline oil was obtained under Coumarin 120 dye laser pumping. The pulses of the laser radiation with the beam divergence of 2 ÷ 5 mrad at the wavelength of about 680 nm, duration of 10 ns and energy of 83 μJ were obtained under pulsed pumping with the energy of 1.34 mJ. The real and slope efficiencies of the LiF:F2 slurry laser reached 6.2% and 12.9% correspondingly.
Mechanistic insight into how gonadotropin hormone receptor complexes direct signaling†
Authors: Johnson Gillian P , Jonas Kim Carol 
Published: December 2019

AbstractGonadotropin hormones and their receptors play a central role in the control of male and female reproduction. In recent years, there has been growing evidence surrounding the complexity of gonadotropin hormone/receptor signaling, with it increasingly apparent that the Gαs/cAMP/PKA pathway is not the sole signaling pathway that confers their biological actions. Here we review recent literature on the different receptor–receptor, receptor–scaffold, and receptor–signaling molecule complexes formed and how these modulate and direct gonadotropin hormone-dependent intracellular signal activation. We will touch upon the more controversial issue of extragonadal expression of FSHR and the differential signal pathways activated in these tissues, and lastly, highlight the open questions surrounding the role these gonadotropin hormone receptor complexes and how this will shape future research directions.
Loss of Fbxw7 in Sertoli cells impairs testis development and causes infertility in mice†
Authors: Zhang Hanbin , Chen Feilong , Dong Heling , Xie Minyu , Zhang Huan , Chen Yan , liu Hong , Bai Xiaochun , Li Xuemei , Chen Zhenguo 
Published: December 2019

AbstractF-box and WD-40 domain protein 7 (Fbxw7) is a component of the Skp1-Cdc53/Cullin-F-box-protein complex (SCF/β-TrCP), which is an E3 ubiquitin ligase that mediates protein degradation. This complex has recently been shown to negatively regulate spermatogonial stem cell self-renewal; however, its roles in Sertoli cell (SC) proliferation, differentiation, and function remain to be established. In this study, we generated conditional mutant mice with SC-specific deletion of Fbxw7 via the Cre-loxP system. Fbxw7 deficiency in SCs impaired testis development, which is characterized by age-dependent tubular atrophy, excessive germ cell loss, and spermatogenic arrest, and the mutant males were infertile at 7 months old. Fbxw7 ablation also compromised cytoskeletal organization and cell polarity of SCs, as well as integrity of the blood-testis barrier. In addition, the transcript levels of cell markers for germ cells, Leydig cells, and SCs were significantly decreased in Fbxw7 mutant mice. Importantly, protein levels of GATA-4, a transcription factor that plays a crucial role in SC maturation and testis development, were progressively decreased in control SCs after postnatal day 14, whereas levels were aberrantly elevated in Fbxw7-deleted SCs. Interestingly, the Gata-4 messenger RNA levels remained stable following Fbxw7 deletion. Fbxw7 silencing in SCs also induced progressive Leydig cell inefficiency and testosterone insufficiency. Collectively, these results demonstrate that Fbxw7 expression is required for SC maturation and function, potentially through degradation of GATA-4, to support pubertal testis development and spermatogenesis.
Bin Cheng: His Study of International Law and His Inductive Approach to International Law
Authors: Chen Li 
Published: December 2019

Abstract
This paper relies on archival research and interviews with Bin Cheng to trace his study of law at the University of Geneva with Maurice Bourquin and at the University College London, University of London with Georg Schwarzenberger. It focuses on Cheng’s doctoral study and his supervisor’s profound influence on his inductive approach to researching the general principles of law. It provides a panoramic view of the international legal community’s overwhelmingly favourable reactions to the publication of Cheng’s thesis in 1953. Finally, it reveals Cheng’s personal reflections on comparative legal education and the study of international law. In our increasingly inter-connected, integrated and complex society today, public international law scholars of today would certainly benefit from drawing upon Cheng’s experience and wisdom in the conduct of our work.
Age structure of a lizard along an elevational gradient reveals nonlinear lifespan patterns with altitude
Authors: Comas Mar , Reguera Senda , Zamora-Camacho Francisco J , Moreno-Rueda Gregorio 
Published: December 2019

Abstract
Lifespan is one of the main components of life history. Shorter lifespans can be expected in marginal habitats. However, in the case of ectotherms, lifespan typically increases with altitude, even though temperature—one of the main factors to determine ectotherms’ life history—declines with elevation. This pattern can be explained by the fact that a shorter activity time favors survival. In this study, we analyzed how lifespan and other life-history traits of the lizard Psammodromus algirus vary along a 2,200 m elevational gradient in Sierra Nevada (SE Spain). Populations at intermediate altitudes (1,200–1,700 m), corresponding to the optimal habitat for this species, had the shortest lifespans, whereas populations inhabiting marginal habitats (at both low and at high altitudes) lived longest. Therefore, this lizard did not follow the typical pattern of ectotherms, as it also lived longer at the lower limit of its distribution, nor did it show a longer lifespan in areas with optimal habitats. These results might be explained by a complex combination of different gradients along the mountain, namely that activity time decreases with altitude whereas food availability increases. This could explain why lifespan was maximum at both high (limited activity time) and low (limited food availability) altitudes, resulting in similar lifespans in areas with contrasting environmental conditions. Our findings also indicated that reproductive investment and body condition increase with elevation, suggesting that alpine populations are locally adapted.