Physics and Chemistry of Solid State
https://journals.pnu.edu.ua/index.php/pcss
<p style="margin: 0cm; margin-bottom: .0001pt; text-align: justify;">Physics and Chemistry of Solid State is a peer-review academic periodical journal of Vasyl Stefanyk Precarpathian National University. The main topics for manuscripts are related to the modern problems of the physics, chemistry and of the technology of solids state. The journal publishes reviews and original research papers.<br />Journal's issues has been published from 2000.</p> <p><strong><span lang="EN-US">Media identifier (National): R30-02046 </span></strong></p> <p><strong>ISSN <a href="https://portal.issn.org/resource/ISSN/1729-4428">1729-4428</a></strong> (Print) <strong>E-ISSN <a href="https://portal.issn.org/resource/ISSN/2309-8589">2309-8589</a></strong> (Online)</p> <p><strong>CiteScore</strong> 2021 - 0.8, 2022 - 1.1</p> <p><strong>SJR</strong> 2022 - 0.197</p> <p><strong>SNIP</strong> 2022 - 0.362</p>Vasyl Stefanyk Precarpathian National Universityen-USPhysics and Chemistry of Solid State1729-4428The influence of the structure of guard rings on the dark currents of silicon p-i-n photodiodes
https://journals.pnu.edu.ua/index.php/pcss/article/view/6564
<p>The article examines the influence of the guard rings (GR) system structure on the dark currents of responsive elements (RE) and the actual guard rings of silicon 4-element <em>p-i-n</em> photodiodes (PD). The samples were made on the basis of <em>p</em>-silicon by planar technology. Samples with one, two, and three GR were produced. It was found that increasing the amount of <em>n<sup>+</sup></em>-GRs does not reduce the dark current of the REs. But with an increase in the number of <em>n<sup>+</sup></em>-GRs, the probability of an edge breakdown of the <em>n<sup>+</sup>-p</em>-junction in the regions of the exit of the hetero-junction of the GR to the surface increases. It is possible to reduce the levels of dark current of REs and GR by combining <em>n<sup>+</sup></em>- and <em>p<sup>+</sup></em>- guard regions, where <em>p<sup>+</sup></em>-GR is a region of restriction of dark current leakage channels, isotypic with the substrate material. PD was made with <em>p<sup>+</sup></em>-GR on the periphery of the crystal in the form of a concentric ring, as well as with a <em>p<sup>+</sup></em>- region on the entire periphery of the crystal. This makes it possible to reduce the level of of dark current of <em>n<sup>+</sup></em>- GR due to the reduction of the area of collection of charge carriers from the surface. But a significant decrease in the dark current of REs was not observed in such cases. We proposed to carry out boron diffusion in the gaps between REs and between REs and <em>n<sup>+</sup></em>-GR.</p>M.S. Kukurudzіak
Copyright (c)
2023-11-182023-11-1824460360910.15330/pcss.24.4.603-609Flexural Bending and Fatigue Analysis of Functionally Graded Viscoelastic Materials: Experimental and Numerical Approaches
https://journals.pnu.edu.ua/index.php/pcss/article/view/6549
<p>This work synthesized a thermoplastic polymer with varying densities along one direction using additive manufacturing technology to study the dynamic and static characteristics of functionally graded viscoelastic materials (FGVMs). To describe the mechanical properties of FGVMs, an analytical formulation based on the sigmoid-law formulation was proposed. The experimental program is conducted on 3D-printed samples, and various tests are conducted to examine the performance of such materials. Furthermore, the finite element method was used to evaluate the structural system's flexural properties. The influences of FG parameters and geometrical properties on flexural and reverse bending fatigue life are analyzed. The results show that increasing porosity from 10% to 30% at a power-law index (<em>k </em>= 2) reduces bending strength by 31.25 percent and deflection by around 11.2 percent for VE samples. Changing the power-law exponent from 0.5 to 10 increases fatigue strength by 35 %.</p> <p> </p>E.K. NjimS.E. SadiqM.S. Al-Din TahirM.A. FlayyihL. Hadji
Copyright (c)
2023-11-202023-11-2024462863910.15330/pcss.24.4.628-639Growth and microwave properties of layered ferrogarnet structures
https://journals.pnu.edu.ua/index.php/pcss/article/view/7147
<p>The ferrogarnet structures consisting from one- to three- layers of monocrystalline yttrium-iron garnet Y<sub>3</sub>Fe<sub>5</sub>O<sub>12</sub> (YIG) films, two- layered YIG - La,Ga:YIG and two- layered {Y,Sm,Lu}<sub>3</sub>(Fe,Ga)<sub>5</sub>O<sub>12 </sub>-YIG structures were grown by liquid-phase epitaxy (LPE) method on gadolinium - gallium garnet Gd<sub>3</sub>Ga<sub>5</sub>O<sub>12</sub> (GGG) substrates of (111) orientation. The obtained layered ferrogarnet structures were studied by the methods of ferromagnetic resonance (FMR) and magnetostatic wave (MSW) interference. The two- and three- layered YIG structures have a wide FMR line width (∆H). For the three- layered YIG structures with the total thickness of 68-102 μm ∆H = 5,7- 11,5 Oe. The line width ∆H = 0,34 – 1,22 Oe correspond to the two- layered (Y,Sm,La)<sub>3</sub>(Fe,Ga)<sub>5</sub>O<sub>12</sub> – YIG structures with thicknesses from 3 to 65 μm. Individual layers in all structures are characterized by similar or different saturation magnetizations (4πM<sub>s</sub>).The frequency MSW separation in the YIG - La,Ga:YIG layered structure was observed. It was shown that the propagation losses of MSW in one- and two- layered structures increase with decreasing wavelength of MSW and transition to a two- layered structure.</p>S.I. YushchukS.O. Yur`evV.V. Moklyak
Copyright (c)
2023-12-112023-12-1124465666110.15330/pcss.24.4.656-661Ti-rich carboborides in the multi-component high-boron alloy: morphology and elemental distribution
https://journals.pnu.edu.ua/index.php/pcss/article/view/7037
<p>In the article, the characterization of the morphology, chemical composition, and elemental distribution in the Ti-based carboboride M(C,B) in (wt.%) Fe-0.72C-2.75B-5.05W-5.57Mo-10.35Cr-2.60Ti multi-component alloy is fulfilled. The study was performed using optical microscopy, SEM, TEM, and energy-dispersive X-ray spectroscopy. It was found that the carboboride M(C,B) is present in the structure in the form of the equiaxed polygonal particles of a 0.5-7.3 mm mean size. The particles are divided into “duplex” and “uniform” ones. The duplex particles consists of the Ti-rich (75 wt. % Ti) “core” (Ti(C,B)) and the Ti-depleted (47.3 wt. % Ti) “shell” ((Ti,W,Mo,V)(C,B)). The uniform particles are characterized by an even distribution of the elements having a chemical composition close to the “shell”. The ratio of B:C (at. %) is 1:2.5, 1:3.3, and 1:3.2 for the “core”, “shell” and the uniform particle respectively. The chemical formulas of the duplex/uniform M(C,B) inclusions and the mechanism of their formation are proposed.</p>Yu.G. ChabakМ.А. GolinskyiV.G. EfremenkoH. HalfaV.І. ZurnadzhyB.V. EfremenkoE.V. TsvetkovaA.V. Dzherenova
Copyright (c)
2023-12-162023-12-1624470771310.15330/pcss.24.4.707-713Hardware and software for automated examination of defects of hard tissues of teeth after endodontic intervention for fatigue and destruction
https://journals.pnu.edu.ua/index.php/pcss/article/view/7189
<p>The work developed circuit engineering, design and software of the loading machine for automated examination of dental hard tissue defects after endodontics intervention for fatigue and destruction. The advantage of this development is the combination as cyclic loading methods simulating chewing movements and force effects on compression in a compact small-sized case, with low power consumption and small noise level. Thanks to the use of a screw transmission and a stepper motor in combination with a sensitive tensoresistive force sensor, it was possible to achieve high accuracy and resolution of 0.1 microns.</p> <p>A series of tests was conducted on real samples of endodontically treated teeth restored using fiberglass pins and cast metal stump inserts. It is shown that methods of restoring incisors and premolars of the upper jaw with the help of fiberglass pins have an advantage when the residual structure of the tooth is lacking due to a more uniform distribution of deformation stresses, since their elastic modulus is close to the elastic modulus of dentin.</p>B.S. DzundzaY.S. YavorskyV.V. FedoriukM.M. RozhkoU.M. PysklynetsO.I. Bulbuk
Copyright (c)
2023-12-212023-12-2124472272810.15330/pcss.24.4.722-728Computer modeling of charge-discharge processes in series-connected sections in storage batteries
https://journals.pnu.edu.ua/index.php/pcss/article/view/7186
<p>A theoretical analysis of the initial charge and discharge processes in consecutive connected sections of the battery under the action of rectangular pulses was carried out, in particular, their influence on the uniformity of energy accumulation and return. The non-uniformity of energy accumulation and return between sections is shown. The equivalent electrical circuit of both single and serially connected battery sections is given. On the basis of equivalent electrical circuits, computer simulation of charge-discharge processes was carried out in the LT SPICE application program package.</p>I.T. KogutT.M. DemyanchukM.D. Prokopiv
Copyright (c)
2023-12-272023-12-2724478078610.15330/pcss.24.4.780-786Phase equilibrium diagram of Y-Cu-Sb system at 870 K
https://journals.pnu.edu.ua/index.php/pcss/article/view/6888
<p>The interaction of the components in the Y-Cu-Sb ternary system was investigated using the methods of X-ray phase analysis, microstructure, and energy-dispersive X-ray spectroscopy in the whole concentration range at 870 K. At the temperature of investigation Y-Cu-Sb system is characterized by the formation of three ternary compounds: Y<sub>3</sub>Cu<sub>22</sub>Sb<sub>9</sub> (Dy<sub>3</sub>Cu<sub>20+</sub><em><sub>x</sub></em>Sb<sub>11-</sub><em><sub>x</sub></em> structure type, space group <em>F</em><em>-</em>43<em>m</em>, <em>a</em>=1.6614(3) nm), Y<sub>3</sub>Cu<sub>3</sub>Sb<sub>4</sub> (Y<sub>3</sub>Au<sub>3</sub>Sb<sub>4</sub> structure type, space group <em>I</em><em>-</em>43<em>d</em>, <em>а</em>=0.95357(5) nm), YCuSb<sub>2</sub> (HfCuSi<sub>2</sub> structure type, space group <em>P</em>4<em>/</em><em>nmm</em>, <em>a</em>=0.42580(1), <em>c</em>=0.98932(3) nm). The solubility of copper in the binary compound YSb (NaCl structure type) extends up to 8 at. %.</p>L. RomakaYu. StadnykV.V. RomakaA. ZelinskiyP. KlyzubA. Horyn
Copyright (c)
2023-11-202023-11-2024461061510.15330/pcss.24.4.610-615The influence of a permanent magnetic field on the crystallization of calcium carbonate from carbonate aqueous solutions
https://journals.pnu.edu.ua/index.php/pcss/article/view/6801
<p>The effect of a permanent magnetic field on the crystallization of calcium carbonate from carbonate aqueous solutions was studied. Based on the equations for the first- and second-order dissociation constants of carbonic acid, the stability constants of NaCO<sub>3</sub><sup>-</sup> and NaHCO<sub>3</sub><sup>0</sup> complexes, the mass balance and electroneutrality equations, the values of the system components and the ratio between the components of the carbonate subsystem were determined, and it was established that the main species in experimental conditions are СО<sub>3</sub><sup>2-</sup>, NaСО<sub>3</sub><sup>-</sup> and HСО<sub>3</sub><sup>-</sup> and the main components of the carbonate subsystem are СО<sub>3</sub><sup>2-</sup> (86.7%) and HСО<sub>3</sub><sup>-</sup> (13.19%). Studies have shown that with a significant excess of CO<sub>3</sub><sup>2-</sup> over HCO<sub>3</sub><sup>-</sup> ions in the solution at temperatures of 18-20˚C, calcite and vaterite are most likely formed. During the crystallization of calcium carbonate from an aqueous carbonate solution in a magnetic field of 125-250 mT, the size of the crystallites increases significantly compared to the absence of a magnetic field.</p>V.R. GayevskiiB.D. NechyporukS.G. Gayevska
Copyright (c)
2023-11-202023-11-2024461662210.15330/pcss.24.4.616-622Green synthesis of silver nanoparticles from whole plant extract analyzed for characterization, antioxidant, and antibacterial properties
https://journals.pnu.edu.ua/index.php/pcss/article/view/6828
<p>In this analysis, A green synthesis method utilizing a plant extract derived from <em>Rumex nepalensis (spreng)</em> was employed to synthesize silver nanoparticles. The synthesized nanoparticles were thoroughly characterized for their structural, surface morphological, optical, antioxidant, and antibacterial properties. Structural analysis revealed a face-centered cubic structure, while FTIR analysis confirmed the presence of biosurfactant molecules in the leaf extract that acted as reducing agents. SEM and TEM analyses further confirmed the spherical shape of the nanoparticles, with a size range of 19-28 nm. The evaluation of the silver nanoparticles demonstrated their antioxidant and antibacterial properties. These nanoparticles exhibited activities in both antioxidant and antimicrobial realms, showcasing their potential as dual-functional agents. This study highlights the effectiveness of the green synthesis method using <em>Rumex nepalensis (spreng)</em> extract for the production of silver nanoparticles with desirable properties for various applications.</p>Abhimanyu P. PawarKishor S. NaktodeArvind J. Mungole
Copyright (c)
2023-11-212023-11-2124464064910.15330/pcss.24.4.640-649Properties of Metal Oxide and Pineapple Fiber Reinforced Dental Composite Resin
https://journals.pnu.edu.ua/index.php/pcss/article/view/6607
<p>This study aimed to synthesize fillers in the form of alumina-zirconia-carbonate apatite and pineapple leaf fiber (Ananas comosus (L.) Merr) as matrix reinforcement consisting of UDMA, TEGDMA, and DMAEMA for direct dental restoration applications. The sample consisted of four composite groups with the addition of 0-5% fiber. All composite samples were then tested for hardness, flexural strength, and Scanning Electron Microscope (SEM). The results of the composite hardness test without the addition of fiber were 30.31 VHN. With the addition of 1%, 2.5%, and 5% fiber, the composite has a hardness value of 31.13 VHN, 34.02 VHN, and 27.22 VHN, respectively. The results of the three-point bending test showed that the flexural strength of the sample without the addition of fiber was 1.6 MPa, while the addition of 1%, 2.5%, and 5% fiber resulted in the flexural strength of 2.1 MPa, 2.3 MPa, and 1.8 MPa, respectively. The SEM results show a homogeneous particle dispersion morphology, with various agglomerations and gaps. Composites with the addition of 1% and 2.5% fiber have a narrower gap than without the addition of fiber. This explains the increase in the hardness and flexural strength of the composite.</p>R.I.S. AsriB. SunendarI. DwiandhonoA. Harmaji
Copyright (c)
2023-12-162023-12-1624469269810.15330/pcss.24.4.692-698Experimental investigation and thermodynamic assessment of phase equilibria in the GaTe–AgGa5Te8–Te system below 600 K
https://journals.pnu.edu.ua/index.php/pcss/article/view/7029
<p>Equilibrium <em>T–x</em> space of the Ag–Ga–Te system in the GaTe–AgGa<sub>5</sub>Te<sub>8</sub>–Te part was divided below 600 K into three-phase regions Ga<sub>2</sub>Te<sub>5</sub>–AgGa<sub>5</sub>Te<sub>8</sub>–Te, Ga<sub>2</sub>Te<sub>3</sub>–AgGa<sub>5</sub>Te<sub>8</sub>–Ga<sub>2</sub>Te<sub>5</sub>, Ga<sub>7</sub>Te<sub>10</sub>–AgGa<sub>5</sub>Te<sub>8</sub>–Ga<sub>2</sub>Te<sub>3</sub>, Ga<sub>3</sub>Te<sub>4</sub>–AgGa<sub>5</sub>Te<sub>8</sub>–Ga<sub>7</sub>Te<sub>10</sub>, and GaTe–AgGa<sub>5</sub>Te<sub>8</sub>–Ga<sub>3</sub>Te<sub>4</sub> by the electromotive force (EMF) method. To accomplish accurate experimental data, the following electrochemical cells (ECs) were assembled: (−)IE|NE|SSЕ|R{Ag<sup>+</sup>}|PЕ|IE(+), where IE is the inert electrode (graphite powder), NE is the negative electrode (silver powder), SSE is the solid-state electrolyte (glassy Ag<sub>3</sub>GeS<sub>3</sub>Br), PE is the positive electrode, R{Ag<sup>+</sup>} is the region of PE that contact with SSE. At the stage of cell preparation, PE is a nonequilibrium phase mixture of the well-mixed powdered compounds Ag<sub>2</sub>Te, GaTe, Ga<sub>2</sub>Te<sub>3</sub>, and tellurium, taken in ratios corresponding to two or three different points in each of the mentioned regions. The equilibrium set of phases was formed in the R{Ag<sup>+</sup>} region at 600 K for 48 h with the participation of the Ag<sup>+</sup> ions. Silver cations, displaced for thermodynamic reasons from the NE to the PE of the ECs, acted as catalyst, i.e., small nucleation centers of equilibrium phases. The spatial position of the established three-phase regions relative to the silver point was used to assign the overall potential-determining reactions of synthesis of the ternary AgGa<sub>5</sub>Te<sub>8</sub> and binary Ga<sub>2</sub>Te<sub>5</sub>, Ga<sub>7</sub>Te<sub>10</sub>, Ga<sub>3</sub>Te<sub>4</sub> compounds. For the first time, the values of the standard thermodynamic functions (Gibbs energies, enthalpies, and entropies) of these compounds were determined based on the temperature dependences of the EMF of the ECs.</p>M. MorozP. DemchenkoF. TesfayeM. ProkhorenkoS. ProkhorenkoO. Reshetnyak
Copyright (c)
2023-12-162023-12-1624469970610.15330/pcss.24.4.699-706Modeling of orthosilicate and methanesulfonic acid clusters in aqueous solution
https://journals.pnu.edu.ua/index.php/pcss/article/view/7023
<p>In the work using the quantum-chemical modeling method, the possibility of binding orthosilicate acid with different amounts of methanesulfonate anions was considered. It was demonstrated that methanesulfonic acid forms two hydrogen bonds with a molecule of orthosilicate acid, regardless of the conformation of the cluster itself. According to the results of calculations of energy parameters of systems and frontier molecular orbitals, it was established that the most stable cluster of orthosilicate acid with methanesulfonate anion is [H<sub>4</sub>SiO<sub>4</sub> · 4CH<sub>3</sub>SO<sub>3</sub><sup>–</sup>]. It was also established that the formation of an eight-membered cycle (S–O···H–O–Si–O–H···O) and (S–O···H –O–Si–O···H–С). Furthermore, it was established that there is no significant dependence of the effective charge on the silicon atom on the number of methanesulfonate anions in the inner sphere. Thus, it is theoretically demonstrated that the methanesulfonate anion is able to stabilize orthosilicate acid and reduce the possibility of its dimerization.</p>A.H. MandrykaO.O. PasenkoV.H. VereschakY.S. Osokin
Copyright (c)
2023-12-212023-12-2124473574110.15330/pcss.24.4.735-741Effect of scandium atoms substitution on the two-slab structure of scandate BaGd2Sc2O7
https://journals.pnu.edu.ua/index.php/pcss/article/view/7093
<p>Tetragonal crystal structure (space group <em>P</em>4<sub>2</sub>/<em>mnm</em> (No 136)) of the isovalently substituted BaGd<sub>2</sub>Sc<sub>2-<em>x</em></sub>In<em><sub>x</sub></em>O<sub>7</sub> phase with <em>x</em> = 0.5 was determined by X-ray powder diffraction methods. The crystal structure of BaGd<sub>2</sub>Sc<sub>1.5</sub>In<sub>0.5</sub>O<sub>7</sub> consists of two-dimensional perovskite-like blocks with a thickness of two slabs of (Sc,In)O<sub>6</sub> octahedra connected by vertices. A slab of GdO<sub>9</sub> polyhedra is located between the blocks. There are no direct (Sc,In) – O – (Sc,In) connections between the octahedra of adjacent blocks. They are "stitched" to each other with the help of – O – Gd – O – bonds. Ba atoms are arranged only in the cubooctahedral voids of the perovskite-like block and their coordination number is 12. Analysis of the crystal chemical characteristics of BaGd<sub>2</sub>Sc<sub>2</sub>O<sub>7</sub> and BaGd<sub>2</sub>Sc<sub>1.5</sub>In<sub>0.5</sub>O<sub>7</sub> showed that upon the isovalent substitution of Sc atoms by large In atoms in slab perovskite-like structure leads to increase of the deformation degree of (Sc,In)O<sub>6</sub> octahedra, GdO<sub>9 </sub>interblock polyhedra, increase in average (Sc,In) – O bond length and a decrease the degree deformation of BaO<sub>12 </sub>cuboctahedrons. Such changes lead to the destabilization of the slab perovskite-like structure and determine the limitation of the area of BaGd<sub>2</sub>Sc<sub>2-x</sub>In<sub>x</sub>O<sub>7</sub> solid solutions and the absence of BaGd<sub>2</sub>In<sub>2</sub>O<sub>7</sub> compound.</p>Y.A. TitovN.M. BelyavinaM.S. SlobodyanikO.I. NakonechnaN.Yu. StrutynskaV.V. Chumak
Copyright (c)
2023-12-212023-12-2124474274710.15330/pcss.24.4.742-747Effect of Mn2+ substitution on catalytic properties of Fe3-xMnxO4 nanoparticles synthesized via co-precipitation method
https://journals.pnu.edu.ua/index.php/pcss/article/view/7310
<p>Mn-substituted magnetite samples Fe<sub>3-x</sub>Mn<sub>x</sub>O<sub>4</sub> (x = 0.0; 0.02; 0.05; 0.1; 0.15; 0.2; 0.25) were synthesized using the co-precipitation method. X-ray diffraction patterns confirmed the formation of pure, well-crystallized manganese ferrite with a cubic spinel structure. The crystallites size increases sharply for the minimum degrees of substitution, with a subsequent tendency to decrease with the growth of manganese ions content. The catalytic properties of Fe<sub>3-x</sub>Mn<sub>x</sub>O<sub>4</sub> were investigated for the degradation of oxytetracycline (ОТС) and inactivate <em>E. coli</em>. There is a correlation between particle size and catalytic activity. The Fe<sub>2.95</sub>Mn<sub>0.05</sub>O<sub>4</sub> sample exhibited the highest catalytic activity in the destruction of OTC. The effect of electromagnetic heating (EMH) on the catalytic properties of iron oxides were investigated. The Fe<sub>2.9</sub>Mn<sub>0.1</sub>O<sub>4</sub> sample with electromagnetic heating achieved 100 % efficiency in decomposing 5 mg/L of OTC. Fe<sub>3-x</sub>Mn<sub>x</sub>O<sub>4</sub> samples reduce the number of Gram-negative bacteria <em>E. coli</em> at concentrations of 10<sup>4</sup> and 10<sup>6</sup> CFU/mL. Electromagnetic heating experiments demonstrated high performance, achieving inactivation of 6 logs of <em>E. coli</em> in the presence of Fe<sub>2.98</sub>Mn<sub>0.02</sub>O<sub>4</sub> and Fe<sub>2.95</sub>Mn<sub>0.05</sub>O<sub>4</sub> catalysts within 135 minutes. Studies on ecotoxicity have shown that <em>Daphnia magna</em> is a sensitive bioindicator of residual H<sub>2</sub>O<sub>2</sub> concentration. An increase in the Mn<sup>2+</sup> content in the synthesized catalysts resulted in a decrease in the toxicity of purified water. The study suggests that Mn-substituted magnetite catalysts are effective materials for catalytic decomposition of OTC and inactivation of <em>E. coli</em> bacteria.</p>Nazarii DanyliukIvanna LapchukVolodymyr KotsyubynskyVolodymyra BoychukViktor Husak
Copyright (c)
2023-12-212023-12-2124474876010.15330/pcss.24.4.748-760Impact of Cd+2 substitutions on structural and mechanical properties of Co0.6Ni0.4-xCdxFe2O4 (0.00≤ x≤0.40) system
https://journals.pnu.edu.ua/index.php/pcss/article/view/6590
<p>This article presents the structural and mechanical properties of Co<sub>0,6</sub>Ni<sub>0,4-x</sub>Cd<sub>x</sub>Fe<sub>2</sub>O<sub>4</sub>spinel ferrite nanoparticles. The as prepared samples were characterized by thermo-gravimetric differential thermal analysis to examine their phase transition. TGA/DTA analysis confirmed the reaction is endothermic in nature and the process completion temperature around 714.24oC is good for annealing the prepared ferrite powder. X-ray diffraction pattern revealed, Co<sub>0,6</sub>Ni<sub>0,4-x</sub>Cd<sub>x</sub>Fe<sub>2</sub>O<sub>4</sub> have been well crystallized to spinel crystal structure. The average crystallite size ranging from 14.52nm to 16.92nm. FTIR spectra showed, two significant absorption bands (ν<sub>1</sub> and ν<sub>2</sub>) in between 400 cm<sup>−1</sup>and 600 cm<sup>−1</sup>confirmed the spinel structured ferrites. Morphological observations revealed, the grain size of prepared ferrites lies in the range 0.85 to 0.21 μm. Raman spectra peak positions of both tetrahedral and octahedral sublattice shifted towards higher energy position.</p>P. KashidS.N. MathadMahadev R. Shedam
Copyright (c)
2023-11-182023-11-1824459560210.15330/pcss.24.4.595-602Influence of temperature regimes of synthesis on the structure of glassy GeS2
https://journals.pnu.edu.ua/index.php/pcss/article/view/6799
<p>The effect of synthesis temperature regimes on the structure and some physical properties of glassy germanium disulfide was examined using the methods of dilatometry and Raman scattering of light. It is concluded that the bond angle disorder increases and the formation of stronger Ge–S bonds in the tetrahedral structure depends on the increase in the synthesis temperature of glassy GeS2. Significant changes in the structural grid of glass also occur when the thermal history of the sample varies in the temperature interval of vitrification.</p>I.J. RosolaV.V. TsyhykaM.V. Tsyhyka
Copyright (c)
2023-11-202023-11-2024462362710.15330/pcss.24.4.623-627Magnetic moment of Mn2+ ions that are responsible for the ferromagnetic properties of ZnO:Mn nanocrystals
https://journals.pnu.edu.ua/index.php/pcss/article/view/6840
<p>The calculation of the magnetic moment of Mn<sup>2+</sup> ions in ZnO:Mn (2 at%.) nanocrystals obtained by ultrasonic pyrolysis of aerosol which are responsible for their ferromagnetic properties is given. In order to investigate the influence of structural defects on the value of magnetic moment the samples were heat treated in air. The calculation was performed on the basis of the analysis of magnetization curves and EPR spectra. It was shown that the defective state of ZnO:Mn nanocrystals has a significant effect on the magnetic moment. The values of magnetic moment for the synthesized sample significantly exceed the values of magnetic moment compared to similar nanocrystals obtained by other methods. The assumption is made that this result is due to the presence of an additional component in the magnetization of the defective samples. In addition to the paramagnetism of Mn<sup>2+</sup> ions, there may be the paramagnetism of the defective shell of ZnO:Mn nanocrystals. After the elimination of structural defects by heat treatment of samples in air and in a gas mixture with hydrogen, the magnetic moment for Mn<sup>2+</sup> ions, which form the ferromagnetic properties of nanocrystals, was determined. The value of this magnetic moment is 0.02µB, where µB is the Bohr mangiton. Such ions, according to the model of bound magnetic polarons, are part of ferromagnetic clusters and take part in the formation of the ferromagnetic properties of the samples.</p> <p><strong>Keywords</strong>: magnetic moment, nanocrystals, ultrasonic aerosol pyrolysis, heat treatment, hydrogen.</p> <p> </p> <p> </p> <p> </p>O.V. KovalenkoV.Yu. Vorovsky
Copyright (c)
2023-11-222023-11-2224465065510.15330/pcss.24.4.650-655Energy state of the electronic subsystem of porous carbon material caused by laser irradiation
https://journals.pnu.edu.ua/index.php/pcss/article/view/7293
<p>The changes in the electronic subsystem of a porous carbon material caused by its doping with Mn, Cr, and Fe and laser irradiation were studied by the method of electron paramagnetic resonance. It has been found that Mn doping leads to the appearance of several paramagnetic centers, and laser irradiation facilitates the redistribution of electrons between different states so that their mobility increases due to the transition from the g = 3.9 to the g = 6.0 state. The Mössbauer spectroscopy of porous Fe-doped carbon material indicates the presence of oxygen ligands for iron ions, in particular the formation of octa- and tetra-complexes with redistribution of electron density between iron and oxygen nuclei, and, accordingly, changes in the degree of covalence of the chemical bond from Fe<sup>3+</sup> to Fe<sup>2+</sup>.</p>I.M. BudzulyakL.S. YablonM.M. KhemiiV.O. KotsyubynskyB.І. RachiyV.М. BoychukІ.І. Budzulyak
Copyright (c)
2023-12-122023-12-1224466266910.15330/pcss.24.4.662-669Thick and Thin Film Solar Cells: New Formulation
https://journals.pnu.edu.ua/index.php/pcss/article/view/7146
<p>Solar cells rely on photogeneration of charge carriers in <em>p</em>-<em>n</em> junctions and their transport and subsequent recombination in the quasineutral regions. Several basic issues concerning the physics of the operation of solar cells remain obscure. This paper discusses some of those unsolved basic problems. In conventional solar cells, recombination of photogenerated charge carriers plays a major limiting role in the cell efficiency. High quality thin-film solar cells may overcome this limit if the minority diffusion lengths become large as compared to the cell dimensions, but, strikingly, the conventional model fails to describe the cell electric behavior under these conditions. A new formulation of the basic equations describing charge carrier transport in the cell along with a set of boundary conditions is presented. An analytical closed-form solution is obtained under the linear approximation. It is shown that the calculation of the open-circuit voltage of the solar cell diode does not lead to unphysical results in the new given framework.</p>J.E. Velazquez-PerezO.Yu. TitovYuri G. Gurevich
Copyright (c)
2023-12-122023-12-1224467067410.15330/pcss.24.4.670-674Modeling the deformation of the semiconductor quantum dot with a multilayer shell in a living cell
https://journals.pnu.edu.ua/index.php/pcss/article/view/7125
<p>The model of the semiconductor quantum dot with a multilayer shell and the quantum dot-human serum albumin bionanocomplex, which are contained in a living cell, was constructed. The regularities of changes in deformation of materials of the CdSe-core / ZnS/CdS/ZnS-shell quantum dot with changes in cell elasticity (comprehensive modulus) at different core radii, thicknesses of individual shell layers, and surface concentration of albumin molecules were investigated. It is shown that the presence of human serum albumin on the surface of the quantum dot significantly increases its sensitivity to pressure caused by the surrounding medium (living cell). The obtained results indicate the prospect of using the core-shell quantum dot-human serum albumin bionanocomplexes for the diagnosis of cancer diseases in the early stages. This is due to the fact that such diseases are accompanied by a sharp change in the elasticity of the cell (its elastic constants).</p>O.V. KuzykO.O. Dan'kivR.M. PeleshchakI.D. StolyarchukV.A. Kuhivchak
Copyright (c)
2023-12-132023-12-1324467568110.15330/pcss.24.4.675-681Facile SERS substrates from Ag nanostructures chemically synthesized on glass surfaces
https://journals.pnu.edu.ua/index.php/pcss/article/view/7158
<p>A quick one-step fabrication of efficient SERS substrates by a modified approach based on a silver-mirror reaction (using Tollens’ reagent) is reported. Commercially available microscope slides or cover glass (coverslips) were used as-received, without special surface treatment. In contrast to the commonly used two-step process, the composition of the Tollens reagent was modified to use a single-step process. The obtained rather homogeneous films of densely packed nanoislands are promising for application as substrates for Surface-Enhanced Raman Scattering (SERS), as demonstrated by several different kinds of molecules as analytes. In particular, the achieved level of detection of a standard dye analyte, down to 10<sup>-14</sup> M of Rhodamine 6G, is in the range of best values reported in the literature. Low concentrations of some biomolecules are also detected, such as lysozyme (10<sup>-4</sup> M), adenine (10<sup>-4</sup> M), and salicylic acid (10<sup>-5</sup> M). For some analytes, stronger SERS was observed in the drop, and for others after the solvent was dried. The possible reasons for this effect are described. By applying thermal annealing in the inert gas atmosphere, the Ag film morphology can be partially converted into a coral-like 3D structure that may be advantageous for the localization of the analyte in the “hot spots” and allow additional spectral tunability of the plasmon resonance.</p> <p> </p>N.V. MazurO.A. KapushO.F. IsaevaS.I. BudzulyakA.Yu. BuziashviliY.V. PirkoM.А. SkorykA.I. YemetsO.M. HreshchukV. YukhymchukV.M. Dzhagan
Copyright (c)
2023-12-132023-12-1324468269110.15330/pcss.24.4.682-691Assessing the Effect of Electronic Pseudopotentials and Relativistic Treatments on the Structural and Electrical Properties of GaN: A DFT Study
https://journals.pnu.edu.ua/index.php/pcss/article/view/7043
<p>Applying the principle of Density functional theory, we can calculate various parameters like lattice constant, band gap, band plot, dielectric function plot, refractive index plot, conductivity plot, density of state plot, loss function etc. of GaN. In this work, we use different electronic pseudopotentials with different relativistic treatment studied using Local density approximation functional (LDA-CAPZ) within DFT for GaN. We used to calculate the energy values, lattice parameters change after geometry optimisation and plot the band energies. Electronic structure calculations results are compares taking different electronic pseudopotentials of different cut-off energy having different relativistic approaches. The Density of state plot and partial density of states plot help to studied more about the electronic as well as magnetic characteristics of the GaN sample. Here, we also compare the advantages and disadvantages of different pseudopotentials with different relativistic approaches of the sample. Energy level distribution and partial density of states were compared for all the pseudopotentials with different relativistic treatments, providing insight into the orbital contributions of electrons to the density of levels. Our study provides a deeper understanding into the impact of electronic pseudopotentials and relativistic treatments on the electronic and structural properties of GaN.</p>D. K. DasP. PatnaikS.K. NayakM. Barala
Copyright (c)
2023-12-172023-12-1724471472110.15330/pcss.24.4.714-721Geometric phase for investigation of nanostructures in approaches of polarization-sensitive optical coherence tomography
https://journals.pnu.edu.ua/index.php/pcss/article/view/6995
<p>Proposed paper presents the latest results in the framework of polarization-sensitive low-coherence interferometry related to new approaches for using the geometric phase to reproduce the polarization structure of a biological transparent anisotropic micro (nano) object. The polarization parameters of an anisotropic object are measured in real time on the basis of a modified Mach-Zehnder interferometer. The advantage of using the geometric phase is the diagnostic of polarization anisotropic surface (subsurface) nanosized layers in a non-contact, non-invasive manner.</p>C.Yu. ZenkovaO.V. AngelskyD.I. IvanskyiM.M. Chumak
Copyright (c)
2023-12-212023-12-2124472973410.15330/pcss.24.4.729-734Study of the short-range order of Co-W alloys electrodeposited using pulse current
https://journals.pnu.edu.ua/index.php/pcss/article/view/7058
<p>Pulsed electrodeposition modes allowed to obtain amorphous Co-W alloys. Using X-ray phase and spectral analysis methods, it was established that the deposition modes and the concentration of the amorphizing component (sodium tungstate salts) in an aqueous electrolyte solution affect the amorphization of alloys. The short-range atomic order was studied by X-ray diffraction analysis and the sizes of the regions of ordered arrangement of atoms were determined in X-ray amorphous Co-W alloys obtained by pulsed electrodeposition. The radial distribution function of atoms was analysed. The assumption is made that cobalt and tungsten atoms combine into configurations that are irregular polyhedrons.</p>D.V. GerasimenkoV.V. Tytarenko
Copyright (c)
2023-12-222023-12-2224476176410.15330/pcss.24.4.761-764Copper and Aluminium Electrochemical Corrosion Investigation during Electrolysis and Heating from 20oC to 180oC
https://journals.pnu.edu.ua/index.php/pcss/article/view/6523
<p>Our investigations show that electrochemical corrosion of copper is faster than electrochemical corrosion of aluminium at temperatures below 180°C and electric current density 3,000 A/m<sup>2</sup> (or 30 A/dm<sup>2</sup>=3 mA/mm<sup>2</sup>). We have obtained that aluminium anodes (cylindrical or spherical) dissolve into concentrated NaCl solution during electrolysis more rapidly with temperature increasing while copper anodes (cylindrical or spherical) dissolve more slowly with temperature increasing from room temperature to temperature 180°C. Electric current value also increases with temperature increasing. Really, such result is unexpected. General quantity of the H<sup>+</sup> and Cl<sup>-</sup> ions decreases during electrolysis at all temperatures since the H<sub>2</sub> and Cl<sub>2</sub> gases are formed near electrodes. It decreases electric current value on 1.3%. General quantity of the Cu<sup>+</sup> and Cu<sup>2+</sup> ions decreases with temperature increasing too. We guess that one reason only should be for electric current value increasing: average charge of copper ions increases from +1 at room temperature to +1.5 at 100°C and to +2 at 180°C while charge of aluminium ions remains the same +3. Corresponding mathematical model is proposed for the analysis, and literature experimental data are used too.</p>M.V. YarmolenkoS.O. Mogilei
Copyright (c)
2023-12-272023-12-2724476577310.15330/pcss.24.4.765-773Growth, Surface Morphology and Mechanical Properties of Potassium Hydrogen Sulphate Single Crystals for Antimicrobial and Third-Order NLO Applications
https://journals.pnu.edu.ua/index.php/pcss/article/view/6830
<p>A good quality single crystal of potassium hydrogen sulphate (KHS) has been grown and subjected to characterization techniques including single crystal X-ray diffraction, scanning electron microscope, hardness test, Z-scan and antimicrobial test. The single crystal X-ray diffraction study discloses the orthorhombic system of the KHS crystals. The SEM analysis shows the formation of tiny hillocks in the KHS crystal. Vickers microhardness test was utilized for testing the mechanical hardness of the grown KHS crystals. Moreover, the mechanical parameters such as elastic stiffness constant and yield strength were also determined. The nonlinear optical properties such as nonlinear susceptibility, nonlinear refractive index, and nonlinear absorption coefficient were estimated by Z scan analysis. In addition, antimicrobial activity was performed against certain pathogens for medication applications.</p>K. ThilagaP. SelvarajanS.M. Abdul Kader
Copyright (c)
2023-12-272023-12-2724477477910.15330/pcss.24.4.774-779