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This paper concerns the use of high-resolution images from a Hasselblad H6D - 100c middle format camera in the investigation of wall paintings. The presented investigation, proved the great potential of an image-based approach combined with the used camera for such documentation. The conducted analysis shows that the obtained accuracy allows not only for the investigation of a wall paintings, but also enables a highly precise analysis of details. Such detailed analysis, provides information for a deeper understanding of the history of the investigated wall paintings. In this article, the measurement accuracy in such photogrammetric documentation was verified. The conclusions were reached through a series of analyses, including: the analysis of point detection, the analysis of gradual selection, and the analysis of the number of photos and its impact on the accuracy.

Frame-shaped samples method is commonly used for testing the magnetoelastic characteristics of bulk soft magnetic materials, such as ferrites or steels. However, unusual shape of such samples limits the accuracy of estimation of magnetic path length as well as efficient magnetic cross-section of the samples carried out accordingly to the IEC 60205:2016 standard. Paper presents, how to overcome this drawback with finite elements method. The quality of estimation of magnetic path length and efficient magnetic cross-section of the frame-shaped samples were verified from the point of view of non-linear magnetization characteristics of soft magnetic materials. The results indicate that proper correction of core’s parameters calculated accordingly to the IEC 60205:2016 standard enable significant increase of measurements accuracy of soft magnetic materials’ characteristics.

The paper presents the possibility of using amorphous materials as cores of tensile stress sensors. Application of thermal annealing of the core to increase magnetoelastic sensitivity is presented. Important parts of measuring system are the signal processing circuit of the sensor and the sensor control system. The results of measurements of the characteristics of the sensors with signal processing circuit are presented.

Gas-phase proton affinities (PA) of the carboxylate anions are very important parameters for gas-phase as well as condensed-phase reaction studies. Comparison of the PA values with pKa values of the respective carboxylic acids in solution gives information about the solvation effects on the acidity of these compounds. In the present work we have measured the PA values of about 65 aromatic acids using Cooks’ kinetic method. About 30 of these acids have been investigated previously by other researchers and served as the reference compounds in our work. The results of MS measurements were evaluated using three methods differing by the level of simplification. We found that for the series of the studied acids there were no significant differences between these methods, so even the simplest one, which does not take into account entropy effects, can be used. The case of the only exception: o-hydroxybenzoic (salicylic) acid is discussed. It was also found that the kinetic method can be used for acids whose anions undergo further fragmentation under experimental conditions.

Paper discusses the possible of application of iron-based amorphous Fe77Cr2B16Si5 alloys for tensile force sensors. In proposed sensor uniform stresses were generated in direction of the ribbon ring core axis. As a result stresses were perpendicular to the magnetizing field direction, what increases sensor sensitivity as well as simplified analyses. The results show high magnetoelastic sensitivity of Fe77Cr2B16Si5 amorphous alloy. Moreover, this magnetoelastic sensitivity increases during the annealing process, which is connected with thermal relaxation of amorphous alloy.

This paper describes the fabrication of thin magnetic layers for an LTCC planar-type inductor with a 0.11 mm thickness. The thin ferrite layers were fabricated by tape casting method. Synthesis conditions and X-ray analysis (300 K) of the Ni 0.3 Zn 0.62 Cu 0.08 Fe 2 O 4 ferrite are presented. A pure cubic, Fd 3 m crystal structure was observed for the Ni 0.3 Zn 0.62 Cu 0.08 Fe 2 O 4 ferrite. The complex impedance and dielectric permittivity of Ni 0.3 Zn 0.62 Cu 0.08 Fe 2 O 4 ferrite were determined as a function of temperature (from −55 to 170 °C) and frequency (from 10 Hz to 2 MHz). Dc resistivity was measured in a temperature range from −55 to 170 °C. Magnetization and magnetic hysteresis were measured by a vibrating sample magnetometer (VSM) in an applied magnetic field up to 60 kOe. The inductance and quality factor were measured in a frequency range 0.1–120 MHz. With the help of finite elements method (FEM) simulation it is possible to calculate the elements electrical parameters and optimize the design. This paper presents a magnetic field modelling of an inductor structure.

Paper presents a novel application of magnetostrictive delay lines, which give a possibility of real time monitoring of strain in ceramic components. Magnetostrictive delay line was based on highly magnetostrictive Fe-Si-B amorphous alloy ribbon, mounted outside of ceramic component, what is a new solution for increasing sensor’s sensitivity. Developed specially for this sensor, hybrid digital-analog signal processing unit covers the sample-and-hold integrated circuit. The achived sensitivity and repeatability of the sensor confirms, that such solution is suitable for ceramic machine tool monitoring.

This paper presents the idea of the extension of the Jiles–Atherton model applied for modelling of the magnetic characteristics of Mn–Zn, as well as Ni–Zn ferrites. The presented extension of the model takes into account changes of the parameter k during the magnetisation process, what is physically judged. The extended Jiles–Atherton model gives novel possibility of modelling the hysteresis loops of isotropic materials. For one set of the extended model parameters, a good agreement between experimental data and modelled hysteresis loops is observed, for different values of maximal magnetising field. As a result, the extended Jiles–Atherton model presented in the paper may be applied for both technical applications and fundamental research, focused on understanding the physical aspects of the magnetisation process of anisotropic soft magnetic materials.

The paper presents a new idea of extension of the Jiles-Atherton-Sablik model for modeling of the influence of mechanical stresses on magnetic hysteresis loops of amorphous alloys. In the extended model changes of parameter k are considered during the magnetization and the influence of stresses on eight parameters of the Jiles-Atherton-Sablik model is taken into account. Verification of the model was carried out on the base of experimental results obtained for Fe40Ni38Mo4B18 amorphous alloy subjected to both stress from external compressive force as well as shearing stresses from torque. In the experiment uniform stress distribution was achieved in both cases due to special mechanical system of backings. Evolutionary strategies were used in conjunction with gradient optimization for calculation of the model parameters. Results of simulation are in good agreement with experimental findings. As a result the extended Jiles- Atherton-Sablik model enables modeling of the magnetoelastic characteristics of amorphous materials for mechatronic inductive components such as compressive stress and torque sensors.

This paper presents the experimental results of the magnetic and magnetoelastic investigation on the properties of Fe70Ni8Si10B12 amorphous alloy, subjected to thermo-magnetic treatment. Samples were annealed at temperature 350◦C for 1 hour, in parallel magnetic field (4 kA/m), as well as in transverse field (350 kA/m). Sample annealed without magnetic field was also tested. Magnetoelastic tests were performed under uniform compressive stress, applied to the ring-shaped core, perpendicularly to the direction of magnetizing field. The results indicated that the thermo-magnetic heat treatment changes the magnetic characteristics, but does not have a significant influence on the coarse of magnetoelastic characteristics of Fe70Ni8Si10B12 amorphous alloy.

The investigation presented in this paper was carried out on ribbon ring samples annealed for 1 hour at various temperatures (T a = 410, 440, 470, 500 and 580 °C) in order to achieve different stages of nanocrystallization and different magnetic properties. To achieve the full description of crystallization process, both X-ray diffraction method (XRD) as well as differential scanning calorimetry (DSC) were utilized. For magnetoelastic tests, nonmagnetic cylindrical backings were used in order to obtain uniform compressive stresses and enable sample to be wound. In this paper the changes of flux density B as a function of compressive stresses σ (for constant values of the magnetizing field H) for samples at different stages of nanocrystallization are presented.

This paper presents the results of investigation of the influence of nanocrystallization process on magnetoelastic properties and structure of Fe73.5Nb3Cu1Si16.5-xB6+x (x=0; 3) alloys. The magnetoelastic investigation was carried out on ring cores. During the magnetoelastic tests the compressive force (F) was applied perpendicularly to the direction of the magnetizing field (H) in the sample. In the paper the stress dependences of magnetic hysteresis loops as well as changes of flux density B as a function of compressive stresses σ (for constant values of the magnetizing field H) are presented. The experiment was carried out on both alloys after different stages of nanocrystallization. The obtained results confirmed that heat treatment influences not only magnetic but also magnetoelastic properties of Fe73.5Nb3Cu1Si16.5-xB6+x (x=0; 3) alloys.

The paper presents new possibilities in the field of construction of the magnetoelastic stress and force sensors. Two methods of applying mechanical stress to the core of the magnetoelastic sensing elements were presented. The first one is suitable for bulk magnetic materials, such as ferrites. The second method can be utilized in a case of both ribbon and bulk ring cores. Such ring-shaped cores can be made of amorphous alloys as well as ferrites. Both these methods enable achieving uniform distribution of stresses in the samples with closed magnetic circuit. The experiment was performed on high permeability Mn–Zn ferrite and Co-rich amorphous alloy. The results confirm, that magnetic properties of both ferrite and amorphous alloys change significantly under compressive stress from the external forces. The relative changes of the permeability exceed 100% for stresses up to 25 MPa. Paper presents also functional characteristics of the magnetoelastic sensor which operate in the resonant circuit configuration. Output frequency signal from the sensor operating in this configuration is suitable for further digital processing.

This paper presents results of investigation of the stress sensitivity of the fluxgate sensor with amorphous alloy (CoFe) 89 (MnMoSiB) 11 (Vitrovac 6150F) ring core. Stress was applied in two directions: perpendicularly to the flux density in the ring core or in the direction of diameter of the ring. The influence of mechanical stress from the external forces on magnetic properties of this ring core was measured. Then results of this testing were used in computer simulation of the influence of the stress on the output signal of the fluxgate sensor.

This paper presents results of an investigation on the magnetoelastic properties of ferrites. Two ferrite samples with different magnetocrystalline anisotropy were investigated: Mn 0.51 Zn 0.44 Fe 2.05 O 4 high permeability ferrite and Mn 0.70 Zn 0.24 Fe 2.06 O 4 ferrite for power application. The influence of stresses on hysteresis loops and permeability of the investigated ferrites is presented. It is shown that in Mn-Zn ferrites with λ s 0 the Villari point occurs for a 0 and that these ferrites exhibit for |σ| 0 considerable magnetoelastic sensitivity, in spite of their small |λ s value. It is shown that the influence of stresses on the magnetic parameters of the materials should be taken into consideration in the case of construction of ferrite components.

This paper presents results of investigations on the magnetoelastic Villari effect in nanocrystalline Fe 73.5 Nb 3 Cu 1 Si 13.5 B 9 alloy. The investigations were carried out using a ribbon ring sample. A special cylindrical backing was used in order to obtain uniform compressive stresses -a in the sample. The experiment was performed for compressive stresses up to 10 MPa. The changes of flux density B(-a) were investigated as a function of compressive stresses -a for different values of the magnetizing field. Significant changes of the flux density B and the Villari point were detected. The experimental results are discussed.

This paper presents a new method of applying stresses to an amorphous ring core. Due to the special cylindrical backings, compressive stress is applied perpendicular to the direction of flux density. In this method the distribution of stresses in the core is uniform and known. This method was used to investigate magnetoelastic properties of a ring core made of Fe 40 Ni 38 Mo 4 B 18 amorphous alloy. The changes of quasi-static hysteresis loops, flux density and permeability for compressive stresses up to 10 MPa are presented. Permeability at H m = 1.5H c decreases over 40% for stresses up to 10 MPa. These experimental results confirm that the presented method may be very useful in the construction of stress transducers.

Initial curve, major and minor magnetostriction hysteresis loops of the NiFe2O4 ferrite as the functions of static magnetic field were investgated. Magnetostriction hysteresis loops as the functions of static induction are also presented. The experimental phenomenon of “liftoff” value of the magnetostriction loop is detected.

This paper presents results of the experimental investigation on the tensile stress dependence of signal transmission of the magnetostrictive delay line based on amorphous ribbon. These results create possibility of novel application of the magnetostrictive delay lines for real-time monitoring of ceramic components. Such ceramic components are commonly used in machine industry, where real-time tool monitoring is required from the practical point of view. Experimental results presented in the paper indicate that the magnetoelastic wave amplitude decreases with the value of stresses in the rod. This creates possibility of application of the developed methodology for the real-time monitoring of ceramic components in machine industry.

This paper presents results of the investigation on a novel solution in construction of the magnetoelastic torque sensors. In this solution, ribbon ring-shaped magnetic materials based on both iron and nickel were used. Due to a special backing glued to the ring-shaped core the uniform stresses under the influence of the torque can be achieved. As a result magnetoelastic properties under the influence of the torque can be tested. For investigation both Fe 78 B 13 Si 9 and Fe 40 Ni 38 Mo 4 B 18 alloy compositions in as-quenched and annealed state were used. In annealed Fe 40 Ni 38 Mo 4 B 18 core, under the torque equal 4 Nm, was observed a decreasing of flux density from 301 to 108 mT.

This paper presents results of the calculation of torque stress dependence of the magnetic properties of Fe78Si13B9 amorphous alloys in the as-quenched state. Mathematical simulation according to Jiles–Atherton–Sablik (J–A–S) model was made on the basis of experimental results. In the experiment, the uniform torque was applied by special, nonmagnetic backings. For precise calculation of the model's parameters, optimization on the basis of application of evolutional strategies together with Hook–Jeevis gradient optimization was applied. Presented, experimentally confirmed results create new possibilities of the description of the process of magnetization of the amorphous alloy subjected to the torque and quantitative interpretation of the changes of the hysteresis loops.

The magnetoelastic investigation presented in this paper was carried out on ribbon ring samples made of Fe41,5Co41,5Cu1Nb3B13 amorphous alloy annealed for 1 h in different temperatures ( Ta = 20 , 360, 380, 460 and 540 ∘ C ) in order to achieve different stages of nanocrystallization. During the magnetoelastic tests, nonmagnetic cylindrical backings were used in order to obtain uniform compressive stresses and enable sample to be wound. The changes of flux density B as a function of compressive stresses σ (for constant values of the magnetizing field H) for samples at different stages of nanocrystallization are presented. The results indicate, that both magnetic and magnetoelastic characteristics of Fe41,5Co41,5Cu1Nb3B13 alloy are slightly dependent on annealing process.

This paper presents results of magnetoelastic investigation carried out on Fe 78 Si 13 B 9 amorphous alloy both as quenched and after the thermal treatment. New method of applying uniform compressive stresses perpendicularly to the direction of magnetizing field was used. Results confirm that after heat treatment influence of stresses on the properties of the amorphous alloy is higher. This phenomenon is connected with increasing of the contribution of the stress-induced anisotropy energy in the total free energy of the material.

The paper presents results of calculation according to the idea of Jiles–Atherton–Sablik (J–A–S) model, of the stress dependence of the hysteresis loop of the Fe 78 Si 13 B 9 amorphous alloys in as-quenched state. Mathematical simulation was made on the basis of experimental results. In the experiment uniform, compressive stresses were achieved in the ring-shaped sample due to special nonmagnetic backings. Based on the experimental data, corresponding to the J–A–S model, the quantitative interpretation of changes of the model's parameters is presented and discussed.

New method of characterization of magnetoelastic properties of amorphous ring cores is presented. The uniform compressive stresses are applied to the core perpendicular to the magnetic flux direction using special backings. The magnetoelastic properties of the amorphous Fe78 Si13 B9 ring core were investigated by the described method. The effect of stress up to 30 MPa is presented.

The relationship between magnetoelastic properties and microstructure has been studied for a series with different bulk density of Mn 0.70 Zn 0.24 Fe 2.06 O 4 ferrite for switch mode power supplies applications. It is shown that in investigated ferrites, in spite of their small λ s value (equal 0.6×10 −6 ), the effect of stress is considerable. The course of magnetoelastic characteristics B ( σ ) H and H c ( σ ) H of investigated Mn–Zn ferrites depends significantly on its microstructure.

The results of magnetoelastic investigation in Mn0.51Zn0.44Fe2.05O4 high-permeability ferrite are presented. The obtained results are compared with the energy-based Jiles–Atherton–Sablik model of the magnetization process. Dependence of model's parameters on compressive stress up to 60 MPa is presented.

The relationship between magnetic induction B, and compressive stress −σ in Mn–Zn ferrites, of very low magnetostrictive constant λs, were investigated. The Villari effect and its technical importance is discussed. It is shown that in Mn–Zn ferrites, with λs≈0, the Villari point occurs for σ≈0 and that these ferrites exhibit, for σ ≫0 , considerable magnetoelastic sensitivity — in spite of their small λ s value. Hence, a low magnetostriction constant λs does not exclude the possibility to apply such materials in magnetoelastic sensors.

Initial curve, major and minor magnetostriction hysteresis loops (butterfly loops) as the functions of the static magnetic field of the Co 0.004 Cu 0.12 Ni 0.866 Fe 2.01 O 4.02 ferrite were investigated. The saturation magnetostriction for the field equal to 2500 A/m was negative and equal to −11.1×10 −6 and for the field of 540 A/m (equal to 3 H c ) was equal to −8.0×10 −6 . Other minor magnetostriction hysteresis loops are presented.

Problems of measurement which cause difficulty in investigating the magnetostrictive properties of ferrites under stresses are concerned with: (i) considerable brittleness of ferrites, (ii) non-uniform distributions of applied stresses on investigated sample, (iii) small values of λ s of ferrites. In this paper the above problems are discussed.

The effect of stress-dependent magnetostriction λ∣ and λ⦜ in Ni-Zn ferrites containing cobalt is investigated. Under applied compressive stress the magnetostriction changes its sign at some -σ value which corresponds to the -σ value of the Villari point.

The relationships between the magnetic flux density B , and compressive stresses σ (up to 100 MPa) in Ni-zn ferrites containing cobalt are presented. The dependence of B (σ, H ) characteristics on magnetocrystalline properties are discussed and the experimental data concerning to this problem are given.

The paper presents results of magnetoelastic investigation carried out on Fe 40 Ni 38 Mo 4 B 18 alloy in as quenched and annealed state. Special nonmagnetic backings were used in order to obtain the uniform stresses in the core and enable sample to be winded. The changes of the magnetic characteristics, as a function of the compressive stresses, for both samples are presented. Results confirmed that the thermo-magnetic improvement of the magnetic properties of Fe 40 Ni 38 Mo 4 B 18 amorphous alloy induces significant changes of its magnetoelastic characteristics.

The possibility of utilizing the magnetomechanical Villari effect in ferrite for the construction of transducer for measuring stresses has been investigated. The sensitivity, linearity and hysteresis of the output voltage against applied stresses characteristic of the transducer is presented.

The relationships between the induction B and compressive stress —σ, in the presence of a small constant magnetic field H0, in ferrites are presented. It is shown that the B(-σ)H0 relations depend both on the magnetostrictive properties of the ferrite and its magnetocrystalline anisotropy and granular structure.

The relationship between magnetic flux density B , and stress σ in ferrites is presented. The origin of the Villari effect and its technical importance is discussed. It is shown that the position of the Villari point and piezomagnetic sensitivity depend on the same properties of a material as those governing the B ( H ) relation.

The λ (H) relation for Ni-Zn ferrites with the addition of a small amount of cobalt was measured up to H = 30Hc. Series of samples of two basic chemical compositions have been investigated: of 50 mol% Fe2O3 and with a small excess of iron. It is shown that: (1) the dependence of λ on cobalt content is different for the two types of ferrite in accordance with the difference in their magnetocrystalline anisotropy; (2) these differences in magnetostrictive effects do not arise solely from the Fe2+ ion content in iron-excess ferrite; (3) the value of λ depends on the granular structure of the cores and it is higher for the dense ferrites even when they contain much more Fe2+ ions than those of standard density. This means that the magnetostrictive effects can be controlled by all the physical and chemical factors which have an influence on the domain structure.

The influence of a small cobalt content on the magnetostriction of Ni-Zn ferrites has been investigated and is discussed. It is shown that, as in the case of a magnetocrystalline anisotropy, the value of λ s may in this case be quite different from that expected. The results prove that, in spite of common opinion, there are no “piezomagnetic obstacles” to introducing Co ions into Ni-Zn ferrites, when the diminishing of their magnetic loss factor in high frequency range is needed.

The dependence of localization of the Villari point and piezomagnetic sensitivity on the magnetostriction and other material properties are discussed. The discussion is based on B(σ)H and λ(H) relations for ferrites of different chemical compositions. By measurements of B(σ)H in the range of both positive and negative values of σ it was confirmed the expectation that the Villari point for the ferrite with λ=0 occurs for σ≈0. Variation of the ZnO content in Ni-Zn ferrite can be used to control the piezomagnetic sensitivity in a limited range only. The B(σ)H relations seem to be the most explicit data with regard to estimation of the piezomagnetic properties of ferrites.

The paper reports on the deposition of two-component Langmuir-Blodgett films containing poly(3-n-alkylthiophenes) with “film-builders” —low-molecular-weight amphiphilic molecules facilitating film formation. Fatty acids and 3-n-octadecylpyrrole were used as builders. The thicknesses and electric permittivities of the films were determined by measurements of the surface plasmon resonance; it was found that the former parameter is controlled by the length of the builder molecules. The electrical conductivities of the deposited films were of the order of 1 μS/m. The contact with oxides gives rise to an abrupt increase of conductivity by several orders of magnitude, followed by a decrease due to an irreversible destruction of the π-electron system of the polymer.

Paper presents results of investigation on influence of external magnetic field on measuring characteristics of magnetoelastic sensor with ring-shaped core. The core of sensor was made of a high permeability amorphous alloy. External magnetic field up to 4 kA/m was generated by Helmholtz coils. Presented results confirm significant role of the demagnetization in analyze of influence of the external magnetic field on characteristics of the magnetoelastic sensors. Due to demagnetization even strong magnetic field has relatively small influence on the functional properties of the sensor.

The results of an investigation of the influence of thermal annealing on the magnetoelastic properties of Fe 73.5 Nb 3 Cu 1 Si 13.5 B 9 soft magnetic alloy in both amorphous and nanocrystalline state are presented. A new method developed was used to apply uniform compressive stresses to the investigated ring core made of the alloy. The compressive stresses produced by external mechanical forces were applied perpendicularly to the direction of the magnetizing field. Due to the uniform distribution of stresses in the core brittle nanocrystalline alloys may be tested for stresses up to 10 MPa. The results revealed, that process of nanocrystallisation causes significant increase in the stress sensitivity of the Fe 73.5 Nb 3 Cu 1 Si 13.5 B 9 alloy. Moreover the influence of stresses caused by external forces is more significant at relatively low values of the magnetizing field suggesting that these nanocrystalline soft magnetic materials are stress sensitive in the range of technical operation of inductive components based on such materials.