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1

Enhancing pitting corrosion inhibition of AISI 304 stainless steel using a green frankincense-modified ferric chloride solution

Masadeh Sami, Al Khateeb Shadi, Ajlouni Almontaser Bellah

Materials Science Poland

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2023

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Vol. 41, No. 3

85--98

EN

To inhibit pitting corrosion of AISI 304 stainless steel (SS), the effect of different percentages of frankincense addition to a 0.5 M ferric chloride solution was explored in this work for the first time. The samples were investigated for pitting corrosion susceptibility via electrochemical noise (EN) tests, where the current and potential noises were recorded for 10000 seconds, and potentiodynamic polarization. The frequency domain of EN data was analyzed using power spectral density (PSD). Frankincense addition to the ferric chloride solution effectively reduced the pitting corrosion of AISI 304 SS. The pitting inhibition was concluded from the high fluctuations in current noises over the test period, its decreasing amplitude, the greater positive potential, the lower current values, and the lower spectral noise and noise resistances with increasing frankincense additions. Optical microscope images supported pitting inhibition with frankincense addition, where pits decreased in number per mm2 and size. A significant decrease in the pit size and pits mm−2 was observed with the 10 wt.% frankincense addition. It was attributed to the adsorption of the inhibitor on the stainless steel surface, inhibiting the adsorption of chloride ions. Additionally, frankincense addition reduced the corrosion current and increased the corrosion potential positively.

2

Imaging polarimeter with high-accuracy measuring principles in crystal optics

Shopa Mykola, Kobyakov Serhiy, Shopa Yaroslav

Opto-Electronics Review

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2022

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Vol. 30, No. 3

art. no. e141948

EN

An imaging polarimeter based on the principles of high-accuracy polarimetry well known in crystal optics is proposed. The application of scientific digital cameras for performance light measurements leads to precise data on polarizers quality, i.e., maps of extinction ratio and transmission axis. Processing of numerous images, acquired at various settings in the polarizer-sample-analyser system, allows to determine the two-dimensional distribution of the phase retardation of birefringent plates. Several results of imaging polarimetry experiments on birefringent plates demonstrate the impact of multiple light reflections on the measured phase retardation values. Experimental data for LiNbO₃ and SiO₂ crystal plates have been presented, demonstrating the capabilities of the proposed type of imaging polarimeter in the crystal optics studies. This technique also allows the measurement of the eigen wave ellipticities, associated with the optical activity of crystals.

3

Utilization of telecommunication optical routes to power fiber-optic polarization sensors

Vyležich Zdeněk, Kyselák Martin

Optica Applicata

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2022

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Vol. 52, nr 4

565--574

EN

A single-mode telecommunication optical route can be used for reliable power supplies of a remote non-electric temperature fiber-optic polarization sensor, but the optical route, due to many physical factors, affects an immediate state of polarization during the transmission. This negative phenomenon changes the sensitivity of the sensor itself. The thesis proposes two main approaches to solving that problem. The first approach is based on the suitable connection of a depolarizer and linear polarizers. The second approach is based on signal interference, which takes place in a polarization-maintaining fiber coupler. This article also evaluates the advantages and disadvantages of the two approaches and graphically demonstrates the functionality of the fiber-optic sensor, which was tested by applying a container with water of different temperatures. A big advantage of this type of sensor is that it is not necessary to have components, that are dependent on electricity, near the monitored place, where there may be no access to electricity, or the place may be sensitive to an electric charge. Paper demonstrates the possibility of successfully powering the non-electric sensor via a classical optical route.

4

A novel method of elimination of light polarization cross sensitivity on tilted fiber Bragg grating bending sensor

Harasim Damian, Cięszczyk Sławomir

Metrology and Measurement Systems

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2022

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Vol. 29, nr 4

737--749

EN

The article shows the possibility of using TFBG gratings to measure the radius of curvature of fiber bending in conditions of variable polarization of the introduced light. Most of the modern, stable light sources generate light with a high degree of polarization. Due to the spatial asymmetry, the direction of the light polarization plane affects the spectral parameters of individual modes. For this reason, in the measurement systems using TFBGs presented so far it becomes necessary to determine and control the state of light polarization directly in front of the periodic structure. The article presents the determined spectral parameters of the cladding modes which allow bending measurements regardless of the direction of polarization of the introduced light. Thanks to this, the measuring system can be constructed without providing control of the introduced light polarization angle, which makes its construction simpler. When using TFBGs with an angle of 2°, the accuracy of determining the bending radius in the range from 15 mm to 30 mm when changing the angle of the plane of polarization in the full range is 0.318 mm in the case of changes in the transmission coefficient. For changes in the wavelength of the selected cladding mode, the accuracy is 0.3203 mm, with the input light polarization being changed in the range from 0° (P type) to 90° (S type).

5

Polarization tomography of the polycrystalinne structure of histological sections of human organs in determination of the olddamage

Litvinenko Olexandra, Paliy Victor, Vуsotska Olena, Vishtak Inna, Kumargazhanova Saule

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2022

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T. 12, nr 4

31--34

EN

The results of algorithmic approbation of the technique of polarization tomography digital histological study of the age of damageto the myocardium and lung tissue based on the polarization reconstruction of linear birefringence maps are presented. Relationships betweenthe temporal change in the magnitude of statistical moments of 1-4 orders characterizingthe distribution of the magnitude of the degree of crystallization of histological sections of the myocardium and lung tissue and the duration of damage were determined. Established time intervals and accuracyof determining the prescription of damage to the myocardium and lung tissue.

PL

Przedstawiono wyniki algorytmicznej aprobaty techniki polaryzacyjnej tomografii cyfrowej histologicznego badania wieku uszkodzenia mięśnia sercowego i tkanki płucnej na podstawie rekonstrukcji polaryzacyjnej liniowych map dwójłomności. Określono zależnościpomiędzy czasową zmianą wartości momentów statystycznych 1-4 rzędów, charakteryzujących rozkład stopnia krystalizacji skrawków histologicznych tkanki mięśnia sercowego i płuc, a czasem trwania uszkodzeń. Ustalono przedziały czasowe i dokładność określaniapredykcji uszkodzenia mięśnia sercowego i tkanki płucnej.

6

Disinformation and Polarization in the Online Debate During the 2020 Presidential Election in Poland

Domalewska Dorota

Safety & Defense

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2021

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1

14--24

EN

The deliberate manipulation of public opinion, the spread of disinformation, and polarization are key social media threats that jeopardize national security. The purpose of this study is to analyze the impact of the content published by social bots and the polarization of the public debate on social media (Twitter, Facebook) during the presidential election campaign in Poland in 2020. This investigation takes the form of a quantitative study for which data was collected from the public domains of Facebook and Twitter (the corpus consisted of over three million posts, tweets and comments). The analysis was carried out using a decision algorithm developed in C# that operated on the basis of criteria that identified social bots. The level of polarization was investigated through sentiment analysis. During the analysis, we could not identify automated accounts that would generate traffic. This is a result of an integrated action addressing disinformation and the proliferation of bots that mobilized governments, cybersecurity and strategic communication communities, and media companies. The level of disinformation distributed via social media dropped and an increasing number of automated accounts were removed. Finally, the study shows that public discourse is not characterized by polarization and antagonistic political preferences. Neutral posts, tweets and comments dominate over extreme positive or negative opinions. Moreover, positive posts and tweets are more popular across social networking sites than neutral or negative ones. Finally, the implications of the study for information security are discussed.

7

Corrosion Resistance of the Nanostructured X37CrMoV5-1 Steel

Skołek E., Kamiński J., Marciniak S., Świątnicki W. A.

Archives of Metallurgy and Materials

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2020

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Vol. 65, iss. 1

133--140

EN

The aim of this study is to compare the corrosion resistance of X37CrMoV5-l tool steel after nanostructurization and after a conventional heat treatment. The nanostructuring treatment consisted of austempering at 300°C, which produced a microstructure composed of nanometric carbide-free bainite separated by nanometric layers of retained austenite. The retained austenite occurred also in form of blocks which partially undergo martensitic transformation during final cooling. For comparison, a series of steel samples were subjected to a standard quenching and high tempering treatment, which produced a microstructure of tempered martensite. The obtained results showed that the corrosion resistance of steel after both variants of heat treatment is similar. The results indicate that the nanocrystalline structure with high density of intercrystalline boundaries do not deteriorate the corrosion resistance of steel, which depends to a greater extent on its phase composition.

8

Effect of polarized signals on the performance of adaptive antenna arrays

Al Ka'bi Amin H.

Archives of Electrical Engineering

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2020

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Vol. 69, nr 4

857--872

EN

The polarized electromagnetic waves have significant impact on the performance of adaptive antenna arrays. In this paper we investigate the effect of polarized desired and undesired signals on the performance of electronically steered beam adaptive antenna arrays. To achieve this goal, we built an analytical signal model for the adaptive array, in order to analyze, and compare the effect of polarized signals on the output SINRs (signal to interference plus noise ratios) of single-dipole, and cross-dipole adaptive antenna arrays. Based on a proof-of-concept experiment, and on MATLAB simulation results, it will be shown that cross-dipole adaptive antenna arrays exhibit better performance in comparison with single-dipole adaptive antenna arrays in presence of randomly polarized signals. However, single-dipole arrays show better performance under certain operating conditions.

9

Wpływ polaryzacji stężeniowej i konwekcji swobodnej na właściwości transportowe membrany polimerowej

Ślęzaka Andrzej, Batko Kornelia M., Gawrys Weronika, Bajdur Wioletta

Przemysł Chemiczny

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2019

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T. 98, nr 11

1828--1831

10

Polarization properties of nematic liquid crystal cell with tapered optical fiber

Marć Paweł, Stasiewicz K., Korec J., Jaroszewicz L. R., Kula P.

Opto-Electronics Review

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2019

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Vol. 27, No. 4

321--328

EN

In the paper, an extended analysis of the polarization properties of a liquid crystal cell with a biconically tapered single-mode telecommunication optical fiber was presented. These properties are a result of a sample geometry and used LC materials. They were analyzed by using two theoretical models based on the matrix decomposition methods, i.e., polar and singular-value one. By measuring Mueller matrices, information about losses, depolarization, dichroism and birefringence was obtained. In the experiment two types of tested samples filled with well-known 6CHBT and E7 liquid crystals were prepared and all optical parameters were shown as the voltage dependence. The tested samples have dichroic properties and for both models calculated PDL is similar and it increases from 2.6 to 6.6 dB for E7 and from 0.4 to 2.7 dB for 6CHBT with voltage changes within the range of 40 – 190 V. Optical losses simultaneously decrease from 30 dB to 27 dB and from 36 dB to 28 dB, respectively. The birefringence properties cannot be directly comparable due to differences between both applied models but voltage fluctuations of these parameters are not significant. These results confirm expected dichroic properties of designed device and complete knowledge about its working principles. Moreover, presented analysis validates usefulness of the singular-value decomposition model applied to dichroic optical fiber elements.

11

The polarization and coherence behavior of the flat-topped array beam through non-Kolmogorov turbulence

Golmohammady Shole, Ghafary Bijan

Optica Applicata

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2019

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Vol. 49, nr 1

75--88

EN

In the present paper, investigation on the polarization and coherence fluctuations of a flat-topped array beam in non-Kolmogorov atmospheric optics links has been presented. For this purpose, the spectral degree of polarization and coherence at the receiver plane is analytically formulated via the extended Huygens–Fresnel integral and the unified theory of polarization and coherence. The influences of the laser beam parameters and the power law exponent that describes the non-Kolmogorov spectrum of the statistical propagation properties of a partially coherent flat-topped array laser beam has been studied in detail. For the employed parameters, it can be concluded that the increase in the structure constant of turbulence (which is equivalent to the increase in turbulence strength) leads to a fast reduction in the spectral degree of coherence. Moreover, when the power law exponent is 3.1, the spectral degree of coherence exhibits a minimum value in comparison with the Kolmogorov atmospheric turbulence.

12

Comparative studies of the electroreduction of zinc ions from gluconate solutions

Rudnik Ewa, Chat Karolina

Metallurgy and Foundry Engineering

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2019

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Vol. 45, no. 1

19--31

EN

This study considers the role of chloride and sulphate anions in the cathodic reduction of zinc ions from gluconate solutions (chloride, sulphate, chloride-sulphate). Cyclic potentiodynamic and potentiostatic polarization measurements, as well as chronoamperometric experiments, were performed. Electrochemical results were correlated with the speciation of the baths. The experiments revealed the inhibiting effect of sulphate ions on the cathodic process caused by the formation of stable neutral ZnSO4 complex in the sulphate-gluconate bath. It resulted in zinc deposition under a limiting current, with the release of metal cation as a rate-determining step. The less stable ZnGlu+ complex dominated both chloride-containing baths, thus the metal deposition ran under activation control. Independent of the solution composition, the nucleation of zinc occurred according to the instantaneous model.

PL

W artykule przedstawiono rolę anionów chlorkowych i siarczanowych w katodowej redukcji jonów cynku z roztworów glukonianowych (chlorkowy, siarczanowy, chlorkowo-siarczanowy). Przeprowadzono pomiary cyklicznej polaryzacji potencjodynamicznej i potencjostatycznej oraz eksperymenty chronoamperometryczne. Wyniki elektrochemiczne skorelowano ze składem jonowym roztworów. Eksperymenty wykazały hamujący wpływ jonów siarczanowych na proces katodowy w kąpieli siarczanowo-glukonianowej spowodowany tworzeniem się stabilnego obojętnego kompleksu ZnSO4. W rezultacie, w elektrolicie siarczanowym osadzanie cynku zachodziło w warunkach prądu granicznego, a etapem powolnym było uwalnianie jonu metalu z kompleksu. W obecności jonów chlorkowych dominujący kompleks stanowił mniej trwały ZnGlu+, a redukcja jonów cynku zachodziła w warunkach kontroli aktywacyjnej. Niezależnie od składu roztworu stwierdzono natychmiastowe zarodkowanie cynku.

13

2D-Mueller-matrix tomography of optically anisotropic polycrystalline networks of biological tissues histological sections

Trifonyuk L., Baranowski W., Ushenko V., Olarc O., Dubolazov A., Ushenko Yu., Bodnar B., Vanchulyak O., Kushnerik L., Sakhnovskiy M.

Opto-Electronics Review

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2018

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Vol. 26, No. 3

252--259

EN

A new technique of Mueller-matrix mapping of the birefringent structure of biological preparations of human organs tissues is suggested. The algorithms of reconstruction of average values and magnitude of fluctuations of the phase (birefringence) and amplitude (dichroism) of optically anisotropic structure of myocardium and connective tissue component of the vaginal wall histological section are proposed.The magnitudes and ranges of changes in the statistical moments of the 1st-4th order that characterize the distribution of average values and magnitude of fluctuations of birefringence and dichroism of the myocardium and connective tissue of the vaginal tissues histological sections were determined. Joint studies of distributions of the characteristics of phase and amplitude of the anisotropy of myocardium and connective tissue component of the vaginal wall tissues of different states were performed. The cases of various necrotic changes in the myocardium and pathological conditions of the vagina wall (prolapse of the genitals) are examined. Balanced accuracy of the method of Mueller-matrix polarization-phase and diffuse tomography of optically anisotropic polycrystalline networks in the differentiation of necrotic and pathological changes in human organs is determined.

14

Polarization of the longitudinal Pochhammer-Chree waves

Ilyashenko A. V., Kuznetsov S. V.

Mechanics and Mechanical Engineering

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2018

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Vol. 22, nr 4

1329--1336

EN

The exact solutions of the linear Pochhammer-Chree equation for propagating harmonicwaves in a cylindrical rod, are analyzed. Spectral analysis of the matrix dispersionequation for longitudinal axially symmetric modes is performed. Analytical expressionsfor displacement fields are obtained. Variation of wave polarization on the free surfacedue to variation of Poisson's ratio and circular frequency is analyzed. It is observed thatat the phase speed coinciding with the bulk shear wave speed all the components of thedisplacement eld vanish, meaning that no longitudinal axisymmetric Pochhammer-Chree wave can propagate at this phase speed.

15

VSP polarization angles determination: Wysin-1 processing case study

Zaręba M., Danek T.

Acta Geophysica

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2018

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Vol. 66, no. 5

1047--1062

EN

In this paper, we present an analysis of borehole seismic data processing procedures required to obtain high-quality vertical stacks and polarization angles in the case of walkaway VSP (vertical seismic profile) data gathered in challenging conditions. As polarization angles are necessary for more advanced procedures like anisotropy parameters determination, their quality is critical for proper media description. Examined Wysin-1 VSP experiment data indicated that the best results can be obtained when rotation is performed for each shot on data after de-noising and vertical stacking of un-rotated data. Additionally, we proposed a procedure of signal matching that can substantially increase data quality.

16

Two cases of phase-shifting interferometry for wave front recovery from heterodyne hologram storage: piezoelectric transducer and modulation of polarization

Rodríguez-Zurita G., Vázquez-Castillo J. F., Toto-Arellano N. I., Calderón-Hernández G., Barojas-Gutiérrez E.

Optica Applicata

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2017

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Vol. 47, nr 4

579-590

EN

Heterodyne holographic interferometry is a well-known interferometric technique for high precision measurements of the phase difference between two recorded wave fronts. These wave fronts are typically registered at a given distance from the object under inspection. Although the affinity of heterodyne techniques with the phase-shifting ones is immediate, reports on concrete implemented set-ups from the former type of techniques as adaptations into the second type seems to be not so widely spread as convenient. To illustrate this point, in this communication we demonstrate two phase-shifting methods as applied to heterodyne holograms, each variant using a different shifting method for phase shifting. One method is based on a conventional piezoelectric stack transducer and the other method comprises modulation of polarization. The alternatives that these two techniques offer could be of direct benefit in dynamic holography.

17

The effect of the symmetrical deformation y = xk + 1 on the optimization of the symmetrical multiple channeled white light color filter

Baraket Z., Zaghdoudi J., Kanzari M.

Optica Applicata

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2017

|

Vol. 47, nr 1

19--28

EN

In this paper, we consider a hybrid photonic crystal symmetrically deformed (Bg5/Cu3/Bg5) consisting of the third generation of the copper mean sequence (Cu3), sandwiched between two Bragg mirrors at the fifth generation (Bg5). Our system realizes a polychromatic filter that transmits five wavelengths in the visible spectrum independently of the polarization of the light transverse electric or transverse magnetic. Secondly, the photonic crystal (Bg5/Cu3/Bg5) undergoes the deformation y = xk + 1 (where k is the degree of deformation, x and y are respectively the coordinates of the system before and after the deformation). With a proper choice of the degree of deformation k, this photonic crystal maintains its property of polychromatic filter whose transmission wavelength is independent of the polarization’s state. Thanks to this deformation, we can disperse the optical windows in different spectra of visible light and exactly in the violet, blue, green, and orange light. This system can be used in the fabrication of color filter devices and the white light emitting diodes.

18

Polarization and EIS studies to evaluate the effect of aluminum concentration on the corrosion behavior of SAC105 solder alloy

Liyana N. K., Fazal M. A., Haseeb A. S. M. A.

Materials Science Poland

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2017

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Vol. 35, No. 4

694--701

EN

This paper presents an investigation on corrosion behavior of Sn-1.0Ag-0.5Cu-XAl (X = 0, 0.1, 0.5, 1.0) by means of polarization and electrochemical impedance spectroscopy (EIS) measurements in 3.5 wt.% NaCl solution. The results show that addition of aluminum into SAC105 shifts the corrosion current density and passivation current density towards more positive values. It is also found that with an increase in aluminum concentration in SAC105 solder alloy, the corrosion current density increases and polarization resistance decreases. This suggests that SAC105 with the highest concentration of Al has the lowest corrosion resistance. In this case, the corrosion behavior seems to be attributed to anodic dissolution of aluminum and Sn-matrix.

19

Development of Data Processing Tools for the Analysis of Radargrams in Utility Detection Using Ground Penetrating Radar

Sagnard F.

Journal of Telecommunications and Information Technology

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2017

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nr 3

55--68

EN

The extraction of quantitative information from Ground Penetrating Radar (GPR) data sets (radargrams) to detect and map underground utility pipelines is a challenging task. This study proposes several algorithms included in the main stages of a data processing chain associated with radargrams. It comprises preprocessing, hyperbola enhancing, hyperbola detection and localization, and parameter extraction. Additional parameters related to the GPR system such as the frequency band and the polarization bring data sets additional information that need to be exploited. Presently, the algorithms have been applied step by step on synthetic and experimental data. The results help to guide future developments in signal processing for quantitative parameter estimation.

20

Odbiór zbiorczy polaryzacyjny w środowisku wewnątrzbudynkowym

Magiera J.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

|

2016

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nr 6

281—284, CD

PL

Niniejszy referat dotyczy oceny efektywności odbioru zbiorczego polaryzacyjnego warunkach propagacji sygnałów wewnątrz budynków. W artykule scharakteryzowano warianty odbioru zbiorczego oraz stosowane w nich metody łączenia sygnałów. Ponadto, zdefiniowano wyrażenia służące szacowaniu zysku odbioru zbiorczego dla tych metod. Przedstawiono również metodykę przeprowadzonych badań pomiarowych oraz dokonano analizy wyników tych badań.

EN

This paper concerns the effectiveness of polarization receive diversity in conditions of indoor signal propagation. The article includes a brief review of receive diversity schemes and diversity combining techniques. Expressions used to estimate the receive diversity gain for these techniques are defined as well. Moreover, methodology of conducted field research is presented and analysis of obtained results is provided.