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The experience of modification of ore-thermal production is described. A rectangular furnace is replaced by a round ore-thermal furnace at a retained power supply, namely, a three-phase furnace transformer with star-connected terminals. Unique design solutions are proposed to achieve the maximum possible level of introduced useful power and the minimum inductive reactance of the secondary current lead.

In the modern context, there is an increase in the detection of HIV/tuberculosis co-infection, which makes it difficult to timely diagnose and treat complications of HIV infection and, as a result, it is the cause of death. Today, it has been found that a high incidence of oncological diseases is a feature of HIV infection, and HIV infection is a risk factor for B-cell lymphoma development. The purpose of the work is to introduce the practitioners to the features of manifestation, diagnosis and course of HIV-associated B-cell lymphoma in a patient with multiresistant tuberculosis. Materials and methods. The article deals with a clinical case of our own observations of the multiresistant pulmonary tuberculosis (MRTB) progression in a patient with HIV-associated B-cell lymphoma. The patient underwent inpatient treatment in the Department of Pulmonary Tuberculosis No. 3 of the clinical base of the Phthisiology and Pulmonology Department of ZSMU (Zaporizhzhia State Medical University) in the Municipal Institution “Zaporizhzhia Regional TB Clinical Dispensary” (ZRTBCD), inpatient treatment in the Sophia Specialized Tuberculosis Hospital (SSTBH) № 55, branch of the “Health Center of Ukraine” in the Zaporizhzhia region. The results of our own observations. The patient was in a dispensary for HIV infection, chronic viral hepatitis B and C at an infectious disease specialist for 13 years. For all that, ART was not prescribed, since the patient refused it. Against the background of HIV infection, the patient developed retroperitoneal B-cell lymphoma, which was initially interpreted as tuberculosis of the retroperitoneal lymph nodes and was diagnosed only at autopsy. Additionally, pulmonary MRTB, chronic viral hepatitis B and C were occurred. Despite the effective antimycobacterial therapy for pulmonary MRTB, metastatic lesions of the lungs, liver, parietal and visceral pleura, abdominal lymph nodes, development of bilateral exudative pleurisy with a hemorrhagic component complicated the progressive course of oncologic disease. Given the situation, multiple organ failure developed and progressively increased with severe endogenous intoxication, which caused the death, due to the progressive course of cancer against the background of HIV infection with an extremely low number of CD4 lymphocytes (

Today, 89% of all parasitic diseases are caused by helminthiasis. The annual morbidityof helminthiasis in Ukraine is 1333 cases per 100 thousand population. Their influenceleads to the development of multiavitaminosis with decreased appetite, body weight andresistance to adverse factors and metabolic disorders. Therefore, the issues of effectiveprevention and treatment are extremely relevant.Objective - to conduct a marketing analysis of the range of antiparasitic phytodrugsavailable on the Ukrainian pharmaceutical market and to determine the prospects fortheir further use in medicine.Material and methods. The analysis of the range of drugs, dietary supplements andmedicinal plant raw materials with anthelmintic action available on the pharmaceuticalmarket of Ukraine was conductedResults. 102 trade names in various dosage forms were identified, according to theanalysis of the range of drugs, dietary supplements and medicinal plant raw materialswith anthelmintic action available on the pharmaceutical market of Ukraine. It has beenfound that the range of drugs is mainly represented only by biologically active additives(97.06%). It should be noted that among the drugs there are both one-component dietarysupplements (18.63%) and combined (81.37%). The ratio of shares in the production ofantiparasitic drugs is approximately the same, domestic producers - 48.04% and foreignmanufacturers - 51.96%.Therefore, taking into account the topicality of the parasitic diseases problem, it isadvisable to use phytodrugs because of the action complexity at the expense of thebiologically active substances of plants, the lack of toxicity in contradistinction tosynthetic antiparasitic drugs.Conclusions. The represented phytodrugs and dietary supplements can be used asadditional means for pharmacotherapy improvement of the worm infestations, as well asfor recurrence prevention.

Objective – to consider the method of organization and performance by the students ofthe Pharmacy Faculty of practical tasks when studying flat and round worms – humanparasites in biology classes with the bases of genetics.Brief description of the work. The article analyzes the methodological approaches tothe organization and implementation by students-pharmacists of practical tasks inbiology with the bases of genetics, concerning medical helminthology studied by them.An approximate list and content of tasks of independent educational and research work ofstudents, aimed at the formation of practical skills and competencies necessary for theirfuture professional activity, are adduced.Conclusion. Performing the above tasks of independent educational research in practicalclasses in biology with the bases of genetics, students-pharmacists do not only deepenand consolidate their theoretical knowledge about helminths – human parasites andtheir role in the development of parasitic diseases, but also develop practical skills toidentify them. main representatives, determining the place of helminthiasis among otherinvasive human diseases, measures for prevention of relevant diseases. In the processof performing practical tasks in medical helminthology by students-pharmacists, theformation of integral, general and special competencies is ensured in them.

Toxocariasis is usually transmitted by ingesting invasive eggs from the soil, howeverrecent reports indicate that the pathogen can also be transmitted by ingesting raw meatfrom infected chicken, rabbit or lamb. Also, the infection of infants through mother's milkand transplacental is very relevant now.Objective. The aim of the study was to determine the state of clinical and laboratoryparameters in the case of Toxocara canis invasion in infants, to optimize the principlesof diagnosis and prevention of toxocariasis in infants based on the study of the epidemiological, clinical and immunological characteristics of the course of the invasion,assessment of the severity of the general condition and natural resistance of the organism.Material and methods. 38 children (24 boys and 14 girls) aged from 6 to 12 monthswere examined. During clinical and laboratory examination of children, clinical andepidemiological, biochemical, serological, immunological research methods were used.ELISA samples with an antibody titer of 1:800 and higher were considered diagnosticallypositive. In addition to the history of life and illness, much attention was paid to theepidemiological, allergic and obstetric history.Results. To analyze the frequency and nature of clinical and laboratory manifestations,their correlation with the results of serological studies, all sick children were divided into3 groups. The first group consisted of 16 children with a seropositive reaction and a scoreof 28.94±1.2 (from 24.5 to 34). The second group included 17 children with a seronegativereaction and a score of 6.91±3.1 (from 2 to 11.5). The third group consisted of 5 childrenwith a seronegative reaction and a score of 19.5±1.4 (from 15.5 to 23). An analysis ofthe results obtained and a comparative assessment of the frequency of manifestation ofthe revealed disorders in each group made it possible to establish that such clinical andlaboratory indicators as hypergammaglobulinemia, hypoalbuminemia and leukocytosiswere significantly more often (5, 8 and more times) observed in children of group 1.Anemia and enlargement of the liver were equally common in all three groups. There wereno significant differences in the frequency of manifestations in children of groups 1 and 3of such clinical and laboratory parameters as recurrent fever, increased ESR, pulmonarysyndrome, radiological signs of lung damage, abdominal syndrome, neurologicaldisorders, lymphadenopathy, eosinophilia, which were significantly less common or werenot detected in group 2 children in general. As for eosinophils in the blood, at the samefrequency, more stable and high eosinophilia was observed in children with toxocariasis(from 20 to 42%) than with food allergies (11-20%). Similar results were obtained whenevaluating clinical and laboratory parameters in points (by Glikman). In all children withtoxocariasis and food allergy, the sum of clinical and laboratory parameters exceeded 12scores and significantly differed from the results of group 2. At the same time, the sum ofpoints in children of group 1 was 28.94±3.1 (from 24.5 to 34), and in children of group3 it was 19.5±2.3 (from 19.5 to 23). As for skin manifestations, they were more commonwith food allergies than with toxocariasis.Conclusions. In infants, invasion by toxocara larvae is possible. In addition to theusual routes of infection, there is the possibility of transplacental invasion from amother infected with toxocariasis. For the timely detection of toxocariasis, infants withhypergammaglobulinemia, hypoalbuminemia, leukocytosis with persistent eosinophiliaabove 20% and a score above 20 (according to Glikman) should be examined fortoxocariasis. To clarify the diagnosis and exclude toxocariasis in both the child andmother, it is necessary to conduct serological tests for toxocariasis.

In Ukraine, about 100,000 cases of geohelminthiasis are registered annually, 80%of which are children under 17 years of age. Symptoms of helminthiasis are mild orcompletely absent, but harmful to the body, however, infection of the child's body isespecially dangerous.Objective - to conduct a marketing study of drugs, used for treatment, and identify themain problems of this pathology prevention.Material and methods. A marketing research and analysis of the trade names’ market,analysis of 52 medical records of inpatients and outpatients (children aged 12 to 17years) for worm infestations and medical records of medical institutions in Chernivtsihave been carried out.Results. At the first stage of the research, a statistical study of invasive diseases state wasconducted and the main risk factors for infection were identified. We studied the rangeof antiparasitic drugs available on the domestic pharmaceutical market. Albendazole ismost often used as an active anthelmintic agent, 75% of which are domestic and 25% ofimported production. Preparations with the active substance pyrantel pamoate accountfor 42.8% of domestic production, all others are imported. According to the results of theprocessed medical records of patients several of the most common treatment regimens,which include anthelmintic therapy, the use of enterosorbents and the appointment ofa 5-day course prescription of H1-histamine receptor blockers were chosen. Havinganalyzed the average cost of the day treatment of nematode infestations, we came to theconclusion that the most available complex of group II drugs, the main antihelmintic drugis Zentel.One of the measures to prevent helminthiasis is the use of phytopreparations anddietary supplements based on medicinal plant materials, which, unlike chemicals, arecharacterized by milder properties and less toxicity, the ability not only to affect thepathogen directly, but also to restore the functional state of the organs and systemsaffected by worm infestation.Conclusions. From the offered schemes of pharmacotherapy the most accessible is theuse of a complex which structure includes Сarbowhite, Rolinoz, Zentel. It is promising tostudy the use of phytomedicines both during medical therapy and for prevention.

The problem of parasitosis is quite pressing today, as the morbidity remains one of the most common in the world. According to the statistics, every third inhabitant of the planet is infected with one or another helminth, often 2-3 or even more of their species. In Ukraine 400-600 thousand patients with helminthiasis are registered each year, which is 53% of all infectious diseases, 80% of the identified patients are children. However, based on sales of anthelmintic drugs, the number of infected parasites can be several times higher. Objective - to optimize the reduction of helminthiasis treatment cost by conducting a pharmacoeconomic analysis of the anthelmintic drugs use. Material and methods. In order to monitor the state of the pharmaceutical market of antiparasitic drugs, we analyzed 83 medical records of inpatients (children aged 1 to 14 years) for worm infestations and medical records of medical institutions in Chernivtsi. Results. According to the results of pharmacoeconomic analysis "cost minimization", it was found that in the age category of 1-2 years while using a suspension of «Vormil» and «Zentel», there was no significant difference in the price of drugs for the treatment course. «Angelmex» (45%), «Vormil» (35%) and «Zentel» (15%) are used in the age group of 2-6 years. In the age group of 6-12 years, the choice of drug depends mostly on the dosage form, in 20% of cases more often they choose chewable tablets, due to the more comfortable way of use, regardless of the drug’s price. In the second stage of the research, a pharmacoeconomic analysis of the dietary supplements use for the helminthiasis prevention was performed. The cheapest for the treatment course was «Phytoglistocide» in the form of capsules (126,83 UAH) and syrup (275,88 UAH), and the most expensive - «Vormil Phyto» in the form of syrup (444,6 UAH). Conclusions. According to the results of the conducted researches it has been established that enterobiasis remains the most widespread in the Chernivtsi region area. Albendazole group agents in the form of tablets and suspensions are most commonly used in these helminthiasis treatment. The drugs of choice are «Algelmex», «Vormil», «Zentel», the choice of which depends on the age category.

Today, the parasitic diseases are the most common in the world and occupy one of the first places in terms of prevalence and economic losses. The reasons for this situation, according to experts, are low-quality epidemiologically dangerous water and low compliance with sanitary and hygienic standards. The problem of prevention and treatment remains relevant for almost all countries, including Ukraine. Objective - to conduct a marketing analysis of the range of the domestic pharmaceutical market of antiparasitic drugs. Material and methods. A marketing analysis was conducted using structural, logical, graphical, systematic and content analysis of data from the State Register of Drugs. Results. The first stage of the research was to study the range of antiparasitic drugs represented on the pharmaceutical market of Ukraine. It has been determined that in the pharmaceutical market, according to the State Register of Drugs of Ukraine, 22 names of anthelmintic drugs are registered. It has been established that the drugs, supplied to the domestic pharmaceutical market from every corner of the world, are 12 trade names, among which the leading positions in terms of supply are India and France (23% respectively). Antiparasitic drugs are presented in 3 dosage forms, among which the largest share are tablets - 65.2%, oral suspensions - 30.4%, the least in the pharmaceutical market are phytodrugs with antihelmintic activity (4.6%). The analysis of the registered antihelmintic drugs has shown that 95.6% of the study drugs are available by prescription. Conclusions. It has been found that the largest share of drugs are benzimidazole derivatives, which account for 47.8% of the total range of the studied drugs, the most common among anthelmintic drugs are dosage forms in tablets (65.2%).

Enormous pollution of the environment exacerbates the parasitic situation, which stipulates its urgency. Objective – to generalize medical and biological problems of helminthiasis and to determine the main directions of the disease prevention and treatment. The problem of helminthiasis spread, mechanisms of parasite infection were considered,information concerning parasite development cycles and life expectancy of helminths in the human body were generalized, the impact on the human body and changes in organs and tissues that occur in helminthiasis were determined, peculiarity of the clinical manifestations and disease diagnosis were indicated at, specific features of preventive measures with enterobiosis and the main causes of high incidence of helminthiasis were determined. Conclusion. Development and implementation of a modern strategy of parasitic control, the use of the latest detection methods, timely diagnosis and treatment of patients with helminthiasis and prevention of helminthiasis are the main tasks to ensure the safety of the human life.

The quaternary chalcogenides, attracting much attention in recent time as promising solar energy materials, permit an effective optimization of their composition by the Ge incorporation. In particular, this implies an interest to the Cu2ZnGeS4 compound, which utilization requires, however, a deeper understanding of its electronic properties in general. Here, we investigate magnetotransport of the p-type Cu2ZnGeS4 single crystals, including resistivity, ρ (T), magnetoresistance (MR) and Hall effect, in pulsed magnetic fields up to B = 20 T. The Mott variable-range hopping charge transfer has been established within a broad temperature interval of T between ∼100 and 200 K by investigations of ρ (T) in zero field. The positive and negative contributions to MR have been observed, attributing them to shrinkage of the impurity wave functions by the magnetic field and to the destructive interference of the hopping charge carriers, respectively. Observation of the negative Hall coefficient, RH (T), exhibiting the dependence close to that of ρ (T), gives a strong support to the Mott conduction mechanism in our p-type Cu2ZnGeS4 material. In addition, the conductivity, connected with thermal activation of holes on the mobility edge, Ec, has been identified both below and above the Mott conduction interval. Finally, the joint analysis of the ρ (T) and MR data has yielded a series of important microscopic parameters. These include such details of the hole spectrum in the acceptor band, as its semi-width, W, the density of localized states, g (μ), at the Fermi level, μ, the positions of μ and Ec, as well as values of the localization radius of holes, a, and of the acceptor concentration, NA.

Transport properties of the kesterite-like single crystals of Cu2ZnSnS4, Cu2ZnSnxGe1−xSe4 and Cu2ZnGeS4 are investigated in pulsed magnetic fields up to B = 20 T. The Mott variable-range hopping (VRH) conduction is established by investigations of the resistivity, ρ (T), in all the materials mentioned above within broad temperature intervals of ΔTv4 ∼ 50–150 K, 50–250 K and 100–200 K, respectively. In addition, the Shklovskii-Efros VRH conductivity below Tv2 ∼ 3–4 K, the nearest-neighbour hopping (NNH) charge transfer between T ∼ 250–320 K and the conductivity by activation of holes on the mobility threshold at temperatures outside ΔTv4, respectively, are observed in these materials. In Cu2ZnSnS4, magnetoresistance (MR) contains only a positive contribution, connected mainly to a shrinkage of impurity wave functions by the magnetic field. At the same time, a negative contribution to MR, attributable to interference effects in VRH, is observed in Cu2ZnSnxGe1−xSe4 and, especially, in Cu2ZnGeS4. The joint analysis of the MR and ρ (T) data has yielded important electronic parameters of the materials. This includes widths of the acceptor band W and of the Coulomb gap Δ, the NNH activation energy En, the localization radius a, the acceptor concentration NA and the density of the localized states at the Fermi level, g (μ). A dramatic increase of a in Cu2ZnSnS4 with decreasing T is observed, whereas in Cu2ZnSnxGe1−xSe4 all the parameter W, En, g (μ), a and NA are non-monotonic functions of x. Finally, in Cu2ZnGeS4 the Hall coefficient RH (T) is negative (despite of the p-type conduction), exhibiting the dependence close to that of ρ (T) in the Mott VRH interval.

A modern technique is proposed to calculate the electrical parameters of the characteristic sections of the power-supply circuits of ore-smelting furnaces, namely, laminated stacks, flexible part, and tubular busbars of the power-supply circuit of an electrode. This technique is based on the results of numerical simulation of the electromagnetic field of a set of conductors with the ANSYS software package and on a mathematical model for calculating the inductance of a system of two rectilinear conductors arbitrarily located in space.

The C-N samples were synthesized at 500 °C from melamine and four kinds of pitch. At 50–100 mass % of pitch all samples were single phase nitrogen solid solutions in graphitic carbon. Maximal detected concentration of 22.4 mass % N correspond to solid solution with formula C100H26.8N26.3O3.1. According to infrared spectroscopy the N atoms chaotically substitute carbon. The electric resistivity of samples with 22.4 mass % N was 1.3–67 Ω ∗ m, which is 100–1000 times lower than resistivity of corresponding graphitic carbon without doping (430–6700 Ω ∗ m). The resistivity of graphitic C3N4 is about 1011 Ω∗m.

This paper presents the results of magnetic and microstructural study of cobalt-substituted NiZn ferrite powders, Ni0.5Zn0.3Co0.2Fe2O4, synthesized with the solid-state reaction method. The lattice parameter decreased with Co substitution, as the ionic radius of cobalt is less than that of zinc. Raman spectroscopy showed clear peaks of the A1g, Eg, and F2g modes, revealing cubic spinel structure and good crystallinity of the samples. The saturation magnetization reduced in the substituted sample to 50.28 emu/g at room temperature. In comparison to the bulk ferrite, the powder sample showed pronounced coercivity even at room temperature. The temperature dependence of the magnetization had superparamagnetic curvature, which yielded the effective anisotropy constant equal to 8.832 kJ/m3.

Ni-Zn and Ni-Zn-Co ferrite powders with nominal compositions Ni0.5Zn0.5Fe2O4 and Ni0.5Zn0.3Co0.2Fe2O4 were prepared by the solid-state reaction synthesis with periodic regrinding during the calcination at 1073 K. The structure of Ni0.5Zn0.5Fe2O4 and Ni0.5Zn0.3Co0.2Fe2O4 was refined assuming space group F d-3m. Scanning electron microscopy revealed the average sizes of the crystalline ferrite particles are 130–630 nm for Ni0.5Zn0.5Fe2O4 and 140–350 nm for Ni0.5Zn0.3Co0.2Fe2O4. The room temperature saturation magnetizations are 59.7 emu/g for Ni0.5Zn0.5Fe2O4 and 57.1 emu/g for Ni0.5Zn0.3Co0.2Fe2O4. The coercivity of the samples is found to be much larger than that of bulk ferrites and increases with Co introduction. The Curie temperature tends to increase upon Zn substitution by Co, as well. The temperature dependences of magnetization measured using zero-field cooled and field cooled protocols exhibit large spin frustration and spin-glass-like behavior.

A finite-size scaling of the nanoscale magnetization m on size averaging R of a single vortex in d -wave bulk superconductor is developed using quasiclassical Eilenberger equations. Nanoscaling is anchoring around the linear London approximation for bulk superconductors. Comparing the results with those obtained in local nonlinear approach demonstrated the importance of the nonlocal contribution. Temperature dependences of two-point correlation function χ ( T , R 1 , R 2 ) = m ( T , R 2 ) / m ( 0 , R 2 ) − m ( T , R 1 ) / m ( 0 , R 1 ) with R 2 > R 1 and one-point function χ ( T, R 1 → ∞, R 2) are calculated. It is found that χ ( T, R 1, R 2), R 2 > R 1, is a nonmonotonous function of temperature and changes sign at high temperatures. This nonmonotonous temperature dependence can be understood as a result of competition between various effects i) Volovik effect and nonlocal corrections to superconducting electron density dominating in low temperature range, and ii) current-induced suppression of the order parameter dominating at high temperatures. The introduced nonmagnetic disorder greatly suppresses the low temperature nonlocal and nonlinear effects, leaving the order parameter effects to prevail in the whole temperature range. Nonlocal pairing and tunneling effects are investigated at the superconductor - normal metal border by considering a d -wave superconducting dot ( d -dot) inside a normal diffusive metal. These effects result in a suppression of the supercurrent in the vortex core and are essential in nanodots with relatively small sizes. At sizes larger than a temperature dependent characteristic length the nanoscale physics transforms into bulk solution.

Resistivity, ρ(T), and magnetoresistance (MR) are investigated in the Cu2ZnSnxGe1−xS4 single crystals, obtained by the chemical vapor transport method, between x = 0–0.70, in the temperature range of T ~ 50–300 K in pulsed magnetic field of B up to 20 T. The Mott variable-range hopping (VRH) conductivity is observed within broad temperature intervals, lying inside that of T ~ 80–180 K for different x. The nearest-neighbor hopping conductivity and the charge transfer, connected to activation of holes into the delocalized states of the acceptor band, are identified above and below the Mott VRH conduction domain, respectively. The microscopic electronic parameters, including width of the acceptor band, the localization radius and the density of the localized states at the Fermi level, as well as the acceptor concentration and the critical concentration of the metal-insulator transition, are obtained with the analysis of the ρ(T) and MR data. All the parameters above exhibit extremums near x = 0.13, which are attributable mainly to the transition from the stannite crystal structure at x = 0 to the kesterite-like structure near x = 0.13. The detailed analysis of the activation energy in the low-temperature interval permitted estimations of contributions from different crystal phases of the border compounds into the alloy structure at different compositions.

Thin films of FeCuNbMoSiB have been sputtered on Corning glass substrates with thicknesses varying from 10 to 200 nm with post annealing at 450 °C and 550 °C. Annealing in the presence of the magnetic field applied along the plane of a substrate develops an uniaxial magnetic anisotropy with the in-plane easy axis. Estimation of the effective anisotropy constant from the magnetization measurements gave Keff = 3.23 kJ/m3. Structure and surface of the films were investigated with the X-ray powder diffraction (XRD), resistivity measurements, and Raman spectroscopy. XRD and resistivity analyses show that thermal annealing at 550 °C improves the crystalline fraction and Fe-Si grain size. Raman spectra identified hematite, goethite, magnetite, as well as graphite contamination of film surfaces.

We present an original, easy to implement, reliable method of non-destructive testing of the orientation of carbon nanotubes by magnetic moment measurements performed in three perpendicular directions of magnetic field. Multi-wall carbon nanotubes/polystyrene composites were prepared by stretching and forge-rolling methods with the same nanotube loading. Unusually strong diamagnetic anisotropy in the composites prepared by the stretching method was observed and attributed to an additional diamagnetic response from the polystyrene aromatic rings wrapping the nanotubes. Strong anisotropy of diamagnetic susceptibility of the composites with highly aligned nanotubes correlates with anisotropic electromagnetic response and with improved microwave absorption properties. Both magnetic anisotropy and microwave absorbance is considerably lower in the composites prepared by the forge-rolled method. The magnetic results correlate well with polarized Raman spectroscopy. The research findings contribute to a better understanding of nanotube-polymer interface, alignment mechanisms, and ultimately the optimal design and performance of functional nanotube - aromatic polymer nanocomposites.

This paper presents magnetic properties of manganese substituted barium hexaferrite BaFe12-xMnxO19 single crystals. Crystals of BaFe12–xMnxO19 with x up to 1.5 and sizes up to 8 mm were observed. The influence of Fe substitution by Mn on the magnetic properties was investigated. For the BaFe10.5Mn1.5O19 single crystal samples saturation magnetization reduced from 72 to 63.5 emu/g at room temperature, and Curie temperature decreased from 455 to 380 °C.

Single crystals of barium hexaferrites with compositions BaFe 12 O 19 and BaFe 11.5 Al 0.5 O 19 were grown from carbonate flux. The Al substitution results in a reduction of the unit cell volume from 697.54(7) A 3 for unsubstituted hexaferrite to 695.93(3) A 3 for the Al-substituted phase and the Curie temperature from 450 to 420 °C. The magnetization of BaFe 11.5 Al 0.5 O 19 samples was measured between 3 and 300 K in external magnetic fields of 0.001 and 0.05 T. The temperature dependence of the magnetization at a magnetic field of 0.001 T demonstrates irreversibility, which disappeared at 0.05 T field. Millimeter-wave characterization of BaFe 11.5 Al 0.5 O 19 slabs loaded in a WR-10 waveguide was carried out in the frequency range of 75 to 100 GHz. In this range electromagnetic resonances were observed at the frequencies of 78.6 GHz and 96.3 GHz. The resonant microwave absorption level was controlled by value of bias magnetic field.

Three self-assembled nanogranular composites based on MnAs ferromagnetic inclusions embedded in ZnSnAs 2 semiconductors with MnAs concentration 10, 20, 47 mol.% were synthesized. The samples were studied by X-ray, SEM, AFM, MFM and SQUID methods. It has been shown that the increasing of the MnAs concentration in composite leads to slightly increasing of the size of the magnetic inclusions. Their size depends mainly on the speed of the crystallization, but the shape of the inclusions depends on the type of the interaction between materials. The connection between equilibrium and non-equilibrium structure of the compounds has been demonstrated. Magnetic properties of the ZnSnAs 2 + MnAs samples show ferromagnetic phase transition with the Curie temperature having values from 313 K to 336 K, increasing as a function of the MnAs concentration in the nanocomposite. A small paramagnetic signal is observed at low temperatures due to individual Mn ions randomly distributed in the ZnSnAs 2 lattice. All our samples show only a narrow magnetic hysteresis loop except of the sample with 47 mol.% of MnAs, for which the coercive field increases to about 120 G. The carrier transport of the alloy shows significant influence of the MnAs clusters. All our samples have p-type conductivity with magnetotransport strongly influenced by the presence of the MnAs phase in the nanocomposite samples. The magnetoresistance (MR) of the alloy shows a complex behavior. The grain boundaries and MnAs clusters influence on the amplitude, sign, and temperature of MR.

Fe73.9Cu1Nb3Si13.2B8.9 (Finemet) thin films were deposited on the glass substrates by means of radio frequency sputtering. The films thickness was varied from 10 to 200 nm. Heat treatment at temperatures of 350, 400 and 450 °C were performed for 30 minutes in order to control thin film structural state. The X-ray powder diffractometry revealed that the crystallization of α-FeSi nanograins took place only at 450 °C whilst the other samples stayed in the amorphous state. Relation between the structure and magnetic properties of the films was discussed in the framework of random magnetic anisotropy model and the concept of stochastic magnetic domains. The latter was investigated using magnetic force microscopy (MFM). MFM data showed formation of such magnetic domains only in samples thermally treated at 450 °C. There was a tendency of the magnetic domain size reduction with the thickness decrease. © 2018 The Authors, published by EDP Sciences. The research was supported by the Ministry of Education and Science of the Russian Federation Agreement no. 02.A03.21.0006 and project no. 3.6121.2017.

Adiabatic temperature change, resulting from MCE, is a complex effect depending on in-field behavior of both lattice and magnetic subsystem of the sample. For studying MCE, the understanding of their interplay is crucial. Comparing ΔT ad in different fields (e.g. below, above and far above saturation field) it should be possible to derive contributions from lattice and magnetic subsystems. In this present work we present our study of the MCE in Ni 50 Mn 35 In 15 Heusler alloy in the vicinity of the magnetostructural transition in 1.6 T and 14 T field.

A La0.7Ca0.3Mn0.5Fe0.5O3 (LCMFO) ceramic sample was produced using conventional solid-state reactions. According to the X-ray diffraction data, the obtained sample has an orthorhombic space group Pnma (a = 5.482(2) Å, b = 7.739(3) Å, c = 5.446(3) Å). Magnetic properties of the obtained sample were studied by 57Fe Mössbauer spectroscopy in the temperature interval of 77–423 K. All spectra recorded at room temperature exhibit the presence of trivalent Fe. Mössbauer spectra of the LCMFO sample show the presence of two intensive components: a paramagnetic doublet and a magnetic sextet, and several weak magnetic sextets. Within the investigated temperature range, phase separation and coexistence of a paramagnetic matrix and a phase of nano-sized antiferromagnetic clusters both below and above TN were found. Keywords: 57Fe Mössbauer spectra, Perovskite manganites, Phase separation, Clusters

Recent development of the thin film solar cells, based on quaternary compounds, has been focused on the Ge contain compounds and their solid solutions. However, for effective utilization of Cu2ZnGeS4, deeper investigations of its transport properties are required. In the present manuscript, we investigate resistivity, ρ (T), magnetoresistance and Hall effect in p-type Cu2ZnGeS4 single crystals in pulsed magnetic fields up to 20 T. The dependence of ρ (T) in zero magnetic field is described by the Mott type of the variable-range hopping (VRH) charge transfer mechanism within a broad temperature interval of ~100–200 K. Magnetoresistance contains the positive and negative components, which are interpreted by the common reasons of doped semiconductors. On the other hand, a joint analysis of the resistivity and magnetoresistance data has yielded series of important electronic parameters and permitted specification of the Cu2ZnGeS4 conductivity mechanisms outside the temperature intervals of the Mott VRH conduction. The Hall coefficient is negative, exhibiting an exponential dependence on temperature, which is quite close to that of ρ(T). This is typical of the Hall effect in the domain of the VRH charge transfer.

Synthesis of a new biodiesel fuel, namely, isopropyl ester of rapeseed oil, is described. The performance properties of the synthesized product, other diesel fuels, and petroleum fuels are compared. The results of computational studies of the efficiency indices of diesel engine running on various fuels are furnished. It is concluded that the synthesized biofuel is of a high quality and can be used in diesel engines.

The paper describes experience of reconstruction ore-thermal plant by replacement a rectangular ore-thermal furnace to circular one while keeping same power source — three-phase furnace transformer with star-connected outputs. Original constructive decisions were made to provide minimal inductance of secondary current lead and maximal useful power input.

Polystyrene / iron-filled multi-wall carbon nanotube composite films were prepared by solution processing, forge-rolling and stretching methods. Elongated iron carbide nanoparticles formed because of catalytic growth are situated inside the hollow cavity of the nanotubes. Magnetic susceptibility measurements as well as records of isothermal hysteresis loops performed in three perpendicular directions of magnetic field confirmed that the nanotubes have a preferential alignment in the matrix. Strong diamagnetic anisotropy in the composites emerges not only from the MWCNTs but also from the polystyrene matrix. The polymer sticks to the honeycomb lattice through the interaction of the p-orbitals of the phenyl ring and those of the carbon nanotube, contributing to anisotropic diamagnetic response. The contribution of iron nanoparticles to overall magnetic response strongly depends on nanotube concentration in the composite as well as on matrix-filler non-covalent stacking, which influences magnetic interparticle interactions.

Multi-wall carbon nanotubes filled with iron nanoparticles were combined with polystyrene to evaluate interface interactions and nanotube orientation in composite using magnetic susceptibility measurements. Iron-containing species were introduced into MWCNT cavities as the result of catalytic chemical vapor deposition synthesis using ferrocene as a catalyst source. Polystyrene loaded with certain quantity of MWCNTs was uniaxially stretched to provide the nanotube alignment. Magnetic susceptibility measurements performed in three perpendicular directions of magnetic field confirmed the alignment in the stretching direction. The composites showed a large diamagnetic response in a magnetic field perpendicular to the nanotube axis and low response in a parallel field. In a quantitative sense, anisotropy exceeds by more than an order of magnitude the effect expected from intrinsic susceptibility of nanotubes. Apparently, the graphitic nature of the nanotube lattice results in strong non-covalent interactions with uniaxially stretched polymer matrix, and aromatic rings as side groups of polystyrene align parallel to the nanotube surface, contributing to strong diamagnetism. As magnetic susceptibility is a penetrative but non-destructive type of measurement, it can successfully characterize both the alignment of one-dimensional or two-dimensional carbon allotropies and the arrangement of the macromolecules around them, contributing to the optimal design and performance of nanocomposites.

The generalized London equation in the mixed state of high- κ s -wave pairing superconductors with impurities is considered as a projection of the quasiclassical nonlocal nonlinear Eilenberger theory. Only one fitting parameter – the cutoff parameter ξ h – is used in the theory. The distribution of the magnetic field is calculated self-consistently. Both nonlocal effects originated from extended states between the vortices and bound Andreev states in the vortex are taken into account. Comparison with different analytical nonlocal linear approaches (the Kogan–Gurevich, Amin–Franz–Affleck, Kogan–Zhelezina models) including only extended states is done. The importance of the Kramer–Pesch nonlinear effect and the field dependence of the cutoff parameter is emphasized and their strong influence on the variance of the magnetic field is found. The influence of the impurities on the ratio of the cutoff parameter ξ h and the Ginzburg–Landau coherence length ξ c 2 is considered. Quasiparticle scattering by impurities and lowering of the temperature reduces the value of ξ h to the values much less than ξ c 2 . This is different from the prediction of the local Ginzburg–Landau theory where ξ h is scaled by ξ c 2 . It is found that impurities influence by different way on the cutoff parameter ξ h and the order parameter coherence length ξ 1 . The ξ h decreases monotonously with the impurity scattering time in contrast to the nonmonotonous behavior of ξ 1 . The results can be used for analysis of the μ SR experimental data.

We present an original, easy to implement, reliable method of non-destructive testing of the orientation of carbon nanotubes by magnetic moment measurements performed in three perpendicular directions of magnetic field. Multi-wall carbon nanotubes/polystyrene composites were prepared by stretching and forge-rolling methods with the same nanotube loading. Unusually strong diamagnetic anisotropy in the composites prepared by the stretching method was observed and attributed to an additional diamagnetic response from the polystyrene aromatic rings wrapping the nanotubes. Strong anisotropy of diamagnetic susceptibility of the composites with highly aligned nanotubes correlates with anisotropic electromagnetic response and with improved microwave absorption properties. Both magnetic anisotropy and microwave absorbance is considerably lower in the composites prepared by the forge-rolled method. The magnetic results correlate well with polarized Raman spectroscopy. The research findings contribute to a better understanding of nanotube- polymer interface, alignment mechanisms, and ultimately the optimal design and performance of functional nanotube - aromatic polymer nanocomposites.&nbsp

In Mn-doped InSb single crystals an unusual, for nonmagnetic semiconductors, dependence on manganese concentration have been revealed for magnetization, conductivity, magnetoresistance and the Hall effect in the range NMn= (1÷2)×1017cm-3. Noticeable low temperature magnetization increase was observed at NMn≈1×1017cm-3. Strong correlation between magnetization, specific resistivity, Colossal Magnetoresistance (CMR) and the Hall constant as a function of manganese concentration in InSb(Mn) was revealed on the insulating side of the metal-insulator transition at Ncr=2×1017cm-3 and at temperature below 10K. Simultaneously, an onset of ferromagnetic-like response in the magnetic moment measurements of p-InSb(Mn) at NMn≤Ncr= 2×1017 cm-3 was registered. This experimental evidence fits the pattern of triplet excitons switching off from conductivity and demonstrates weak magnetic ordering. The coincidence in transport, magnetotransport properties of p-InSb(Mn) and uniaxially stressed p-InSb(Ge) crystals puts forward the idea that the unusual InSb(Mn) properties could be related to Jahn-Teller distortions caused by Mn.

We present results of experimental studies of magnetic properties, resistivity and magnetoresistance (MR) of (Co84Nb14Ta2)x(Al2O3)100-x films deposited onto a glass-ceramic substrate by the ion-beam sputtering, focusing on MR in high magnetic fields for compositions close to the percolation threshold (x=47-57 at.%). The samples consist on Co-Nb-Ta metallic nanogranules size of 2-5 nm which are embedded into the non-stoichiometric Al-O matrix. Magnetization was measured by SQUID magnetometer at T=4.2-350 K. MR was studied in the pulsed magnetic fields μ0H up to 20 T at T=70-300 K in three geometries: magnetic field in plane parallel and perpendicular to current, magnetic field perpendicular to plane. The pulse duration was 11-12 ms. For the sample with x=57 at.% the temperature dependence of conductivity follows the lnT behavior that matches a strong tunnel coupling between nanogranules. With decreasing metal volume fraction lnT behavior gradually changes to the T1/2 dependence at 47 at.%. For all samples MR is small (0H0H=20T. Accordingly to structural and magnetic data a large amount of metallic atoms are located between magnetic nanogranules that diminish the tunnel barrier height and make tunnel MR small and weakly dependent on temperature.

Diode structures obtained by vacuum sputtering deposition of Al onto the surface of p-Cd1−xZnxTe (x=0.05) single crystals were studied. In the context of the Sah-Noyce-Shockley model for generation and recombination of charge carriers, a quantitative description of the diodes’ electrical characteristics is attained.

The nanocomposites comprising of anatase titania nanoparticles uniformly distributed inside the porous carbon matrix were synthesized using furfuryl alcohol, tetrabutyltitanate, and nonionic surfactant. The characterization of the nanocomposite by scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray analysis, x-ray diffractometry, and Raman spectroscopy revealed the formation of anatase titania nanoparticles of average sizes 10 to 20 nm. The observed broadening and blueshift of the main Raman peak of titanium dioxide nanoparticles were explained using the phonon confinement effect. The nanocomposite exhibited strong paramagnetism at low temperatures and was diamagnetic at higher temperatures, as well as a small contamination by magnetic impurities was detected. The paramagnetism originated from the amorphous defect-rich carbon and oxygen vacancies in titania.

The mechanism of unconventional superconductivity in recently discovered Fe-based superconductors has been intensively discussed. A plausible candidate is the superconducting (SC) pairing mediated by antiferromagnetic (AFM) interactions. There are two different approaches predicting the s ± pairing state, in which the SC gap shows an s -wave symmetry that changes sign between different Fermi-surface (FS) sheets. The first one is based on the itinerant spin fluctuations promoted by FS nesting, and the second is based on the local AFM exchange couplings. We apply quasiclassical Eilenberger approach to the vortex state to calculate the cutoff parameter, ξh , at different levels of impurity scattering rates and to compare results with experimental data for iron pnictides. The s ± -wave pairing symmetry is considered as a presumable state for these materials. Magnetic field dependence of ξh /ξ c 2 is found to be nonuniversal for s ± pairing: depending on the chosen parameter set it can reside both below and above analytical Ginzburg-Landau curve. It is also found that normalized ξ 2 /ξ c 2 (B/B c 2 ) dependence is increasing with pair-breaking (interband) impurity scattering, and the intraband scattering results in decreasing of the ξ 2 /ξ c 2 value. Here, ξ 2 is the vortex core size and ξ c 2 is the Ginzburg-Landau coherence length determined from the upper critical field. The ξ 2 /ξ c 2 (B/B c 2 ) curve has a minimum at low temperatures and small scattering evolving into monotonously decreasing function at strong scattering and high temperatures.

There is some evidence that the electron-phonon mechanism is not strong enough to produce ob- served high critical temperatures in unconventional superconductors; this is the case in both the cuprates and Fe-based superconductors. The d-wave pairing in strongly correlated systems is consistent with the observation of nodal quasiparticles in the heavily hole doped superconductor KFe2As2 with Tc = 3 K and high-Tc cuprates. In this work the Eilenberger equations are solved for anisotropic dx2−y2 -wave superconductors. The cutoff pa- rameter ξh and vortex core size ξ2 (the distance from the vortex center to the radius where the current density reaches its maximum value) in the mixed state are investigated numerically. The cutoff parameter determines the field distribution in the generalized London equation obtained as a projection of the quasiclassical theory. It can be used for the fitting of the μSR and small-angle neutron scattering (SANS) experimental data. Field and temperature dependences of ξh/ξc2 in dx2−y2 -wave superconductors are similar to those in s-wave super- conductors: ξh/ξc2(B/Bc2) dependence has minimum at high temperatures and shows monotonously increasing behavior at low temperatures. Here, ξc2 is determined by the relation Bc2 =Φ 0/2πξc2 2 . The ξ2/ξc2(B/Bc2) dependence is monotonously decreasing function at intermediate and high temperatures.