scholarly journals Новый метод измерения показателя преломления текущей жидкости

2021 ◽  
Vol 129 (7) ◽  
pp. 954
Author(s):  
В.В. Давыдов ◽  
А.В. Мороз ◽  
Д.И. Николаев
Keyword(s):  
Refractive Index ◽  
Laser Radiation ◽  
Vertical Section ◽  
Experimental Studies ◽  
New Method ◽  
Practical Implementation ◽  
Multiple Reflections ◽  
Optical Elements ◽  
Flowing Liquid ◽  
Flow Through

The necessity of developing a new method for measuring the refractive index of a liquid in a turbulent mode of its flow in a pipeline is substantiated. A new method for measuring the refractive index of a medium n is presented. For its practical implementation, a new design of a flow-through refractometer has been developed, which makes it possible to measure n in both laminar and turbulent fluid flow. A new design of the optical part of the refractometer is considered. A new way of placing it on the vertical section of the pipeline for measuring n is proposed. All this makes it possible to make insignificant the influence on the measurement result of n flowing liquid of errors associated with multiple reflections of laser radiation from optical elements, with the formation of voids or vortex flows in the pipeline and with temperature fluctuations. In the design of a refractometer with a new method for measuring n, there are no restrictions on determining the value of n of a flowing liquid, in contrast to the used industrial flow-through refractometers, the principle of which is based on the phenomenon of total internal reflection of laser radiation at the interface of two media. The results of experimental studies of various media are presented.

scholarly journals Condition monitoring of current media using a differential refractometer

2021 ◽  
Vol 2086 (1) ◽  
pp. 012135
Author(s):  
V I Svyatkina ◽  
V V Davydov ◽  
V Yu Rud
Keyword(s):  
Refractive Index ◽  
Laser Radiation ◽  
Condition Monitoring ◽  
Optical Density ◽  
New Method ◽  
Experimental Investigations ◽  
Refractive Index Measurement ◽  
Flowing Liquid ◽  
Index Measurement ◽  
Differential Flow

Abstract A new design of a differential flow refractometer has been developed to monitor the condition of flowing media in a pipeline. A new method of refractive index measurement has been implemented, taking into account the specifics of flowing and closed cuvette arrangement, as well as the angles of incidence of laser radiation on their walls. The effect of changes in the optical density in the flowing liquid on the refractive index measurement result is determined. The results of experimental investigations of different media are presented.

scholarly journals On the need to control the state of the upper edge of the prism in a flow-through refractometer for measurements with an error less than 10−4

2021 ◽  
Vol 2086 (1) ◽  
pp. 012145
Author(s):  
F A Isakov ◽  
V V Davydov ◽  
V Yu Rud
Keyword(s):  
Thin Film ◽  
Refractive Index ◽  
Measurement Error ◽  
Technological Process ◽  
Experimental Studies ◽  
The State ◽  
Flowing Liquid ◽  
Upper Face ◽  
Flow Through ◽  
Negative Factors

Abstract The article substantiates the need to use a flow-through refractometer to control the state of a flowing liquid during scientific research, when automating a technological process, etc. The main negative factors that affect an increase in the measurement error of the refractive index n of a flowing liquid are determined. It was found that one of these factors is the formation of a thin film (plaque) on the upper face of the prism, which is in contact with the medium under study. The study of the influence of this film on the measurement error has been carried out. A method has been developed to eliminate plaque from the upper face of the prism during the operation of the refractometer. The results of experimental studies are presented.

Design of flowing refractometer with cylindrical insert in the form a vertical pipeline section for control to clear media state

2021 ◽  
pp. 36-43
Author(s):  
Vadim V. Davydov ◽  
Denis I. Nikolaev ◽  
Angelina V. Moroz
Keyword(s):  
Refractive Index ◽  
Laser Radiation ◽  
Experimental Investigations ◽  
Optical Elements ◽  
Flowing Fluid ◽  
Flowing Liquid ◽  
Unbalance Voltage ◽  
Laminar And Turbulent Flow ◽  
Differential Type ◽  
Media Condition

The article a the new design of flowing refractometer of differential type for media condition control both in laminar and turbulent flow regimes is considered. Given the peculiarities of the location of the flow and closed cuvette and the angles of incidence of laser radiation on their walls we have implemented a new method of measuring the refractive index n in new developed design of refractometer. This allowed us to make the influence of a number of errors related with unbalance voltage on the photoelectric converter, with an increase in the number of reflections between optical elements of laser radiation, with the presence of a transport link for the selection of flowing fluid and temperature fluctuations on the result of measuring the refractive index. The technique allowing to reduce the influence of change of the optical density of the flowing liquid on the measurement error of refractive index is proposed. The results of experimental investigations for different media are presented.

scholarly journals Vertically Coupled Plasmonic Racetrack Ring Resonator for Biosensor Applications

Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 203 ◽  
Author(s):  
Kirill V. Voronin ◽  
Yury V. Stebunov ◽  
Artem A. Voronov ◽  
Aleksey V. Arsenin ◽  
Valentyn S. Volkov
Keyword(s):  
Refractive Index ◽  
Ring Resonator ◽  
High Sensitivity ◽  
Light Transmittance ◽  
Practical Implementation ◽  
Refractive Index Sensor ◽  
Plasmonic Waveguides ◽  
Optical Elements ◽  
A Value ◽  
Strip Waveguide

Plasmonic chemical and biological sensors offer significant advantages such as really compact sizes and extremely high sensitivity. Biosensors based on plasmonic waveguides and resonators are some of the most attractive candidates for mobile and wearable devices. However, high losses in the metal and complicated schemes for practical implementation make it challenging to find the optimal configuration of a compact plasmon biosensor. Here, we propose a novel plasmonic refractive index sensor based on a metal strip waveguide placed under a waveguide-based racetrack ring resonator made of the same metal. This scheme guarantees effective coupling between the waveguide and resonator and low loss light transmittance through the long-range waveguide. The proposed device can be easily fabricated (e.g., using optical lithography) and integrated with materials like graphene oxide for providing adsorption of the biomolecules on the sensitive part of the optical elements. To analyze the properties of the designed sensing system, we performed numerical simulations along with some analytical estimations. There is one other interesting general feature of this sensing scheme that is worth pointing out before looking at its details. The sensitivity of the considered device can be significantly increased by surrounding the resonator with media of slightly different refractive indices, which allows sensitivity to reach a value of more than 1 μm per refractive index unit.

scholarly journals Radar Beam Tracing Methods Based on Atmospheric Refractive Index

2014 ◽  
Vol 31 (12) ◽  
pp. 2650-2670 ◽  
Author(s):  
Yuefei Zeng ◽  
Ulrich Blahak ◽  
Malte Neuper ◽  
Dorit Jerger
Keyword(s):  
Refractive Index ◽  
Ad Hoc ◽  
Beam Propagation ◽  
New Method ◽  
Actual State ◽  
Practical Implementation ◽  
Atmospheric Conditions ◽  
Radar Beam ◽  
Snell’S Law ◽  
Snell's Law

Abstract Simulation of radar beam propagation is an important component of numerous radar applications in meteorology, including height assignment, quality control, and especially the so-called radar forward operator. Although beam propagation in the atmosphere depends on the refractive index and its vertical variation, which themselves depend on the actual state of the atmosphere, the most common method is to apply the 4/3 earth radius model, based on climatological standard conditions. Serious deviations from the climatological value can occur under so-called ducting conditions, where radar beams at low elevations can be trapped or propagate in a waveguide-like fashion, such that this model is unsuitable in this case. To account for the actual atmospheric conditions, sophisticated methods have been developed in literature. However, concerning the practical implementation of these methods, it was determined that the description in the literature is not always complete with respect to possible pitfalls for practical implementations. In this paper, a revised version of an existing method (one example for the above-mentioned “pitfall” statement) is introduced that exploits Snell’s law for spherically stratified media. From Snell’s law, the correct sign of the local elevation is a priori ambiguous, and the revised method explicitly applies (i) a total reflection criterion and (ii) another ad hoc criterion to solve the problem. Additionally, a new method, based on an ordinary differential equation with respect to range, is proposed in this paper that has no ambiguity. Sensitivity experiments are conducted to investigate the properties of these three methods. The results show that both the revised and new methods are robust under nonstandard conditions. But considering the need to catch an elevation sign ambiguity in the revised method (which cannot be excluded to fail in rare instances), the new method is regarded as more robust and unproblematic, for example, for applications in radar forward operators.

scholarly journals Определение времени продольной релаксации текущей жидкости ядерно-магнитным спектрометром дифференциального типа

2020 ◽  
Vol 46 (22) ◽  
pp. 46
Author(s):  
В.В. Давыдов ◽  
Н.С. Мязин ◽  
В.И. Дудкин ◽  
Р.В. Давыдов
Keyword(s):  
Flow Rate ◽  
Simultaneous Measurement ◽  
Entire Range ◽  
Relaxation Times ◽  
Experimental Studies ◽  
The State ◽  
Magnetic Spectrometer ◽  
New Method ◽  
T2 Relaxation ◽  
Flowing Liquid

The necessity of simultaneous measurement of the longitudinal T1 and transverse T2 relaxation times for monitoring the state of the flowing liquid during the study in the range of flow rate q changes by at least two orders of magnitude has been substantiated. A new method for measuring T1 has been developed. For its implementation, the design of a differential nuclear magnetic spectrometer has been proposed, which makes it possible to measure T1 in the entire range of measurement of flow rate q. The results of experimental studies are presented.

scholarly journals Optical Sensitivity of Waveguides Inscribed in Nanoporous Silicate Framework

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 123
Author(s):  
Zhong Lijing ◽  
Roman A. Zakoldaev ◽  
Maksim M. Sergeev ◽  
Andrey B. Petrov ◽  
Vadim P. Veiko ◽  
...  
Keyword(s):  
Refractive Index ◽  
Near Field ◽  
Experimental Studies ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Direct Writing ◽  
Sensor Applications ◽  
Refractive Index Contrast ◽  
Optical Sensitivity ◽  
Index Contrast

Laser direct writing technique in glass is a powerful tool for various waveguides’ fabrication that highly develop the element base for designing photonic devices. We apply this technique to fabricate waveguides in porous glass (PG). Nanoporous optical materials for the inscription can elevate the sensing ability of such waveguides to higher standards. The waveguides were fabricated by a single-scan approach with femtosecond laser pulses in the densification mode, which resulted in the formation of a core and cladding. Experimental studies revealed three types of waveguides and quantified the refractive index contrast (up to Δn = 1.2·10−2) accompanied with ~1.2 dB/cm insertion losses. The waveguides demonstrated the sensitivity to small objects captured by the nanoporous framework. We noticed that the deposited ethanol molecules (3 µL) on the PG surface influence the waveguide optical properties indicating the penetration of the molecule to its cladding. Continuous monitoring of the output near field intensity distribution allowed us to determine the response time (6 s) of the waveguide buried at 400 µm below the glass surface. We found that the minimum distinguishable change of the refractive index contrast is 2 × 10−4. The results obtained pave the way to consider the waveguides inscribed into PG as primary transducers for sensor applications.

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