Performance analysis of protective functions of forest plantations of the Lviv railway line (Ukraine)

To reduce the harmful impact of railway transport on the environment and ensure environmental safety, railway enterprises develop and implement a wide range of environmentally effective measures annually. First, it concerns the protection of the territories adjacent to the railroad tracks from various types of pollution. These forest plantations are created for the protection of the railroad track from adverse climatic factors, as well as for the reduction of the railway's impact on the surrounding territories - to reduce the various types of pollution, and to protect from adverse aerodynamic effects. In order to investigate the protective properties of forest plantations, we presented their detailed characteristics on the section of the Lviv-Sambir railway line. This is the busiest railway line in terms of the number of trains, which connects the eastern industrial regions of Ukraine with the western part of the European Union. It transports the largest volumes of cargo, including hazardous ones. The effect of afforestation on reducing the heavy metals content in the soil of the impact area of the railway was determined experimentally. In all samples, the concentrations of heavy metals in the soil do not exceed the maximum permissible concentration standards: Cu-100, Zn-100, Pb-30, Cd-3.0 mg/kg3. However, there is a decrease in the heavy metals' content with the distance from the track. Differences in ingredient pollution depending on the placement of plantations were established. Thus, the concentration of heavy metals is higher on average from 2.6% to 29.9% in the areas on the windward side compared to the areas on the opposite leeward side. Therefore, forest vegetation intensively retains heavy metals and performs the function of a filter for the natural environment. Research has established a reduction in the parametric impact of railway transport. The level of protective plantings' effect on noise reduction along railway lines was determined. The highest noise levels of electric trains were determined at 95-94 dBA near the track, at a distance of 50-100 m the noise level remained high at 90-82 dBA, and at a distance of 150-200 m the noise ranged from 86 to 65 dBA; the highest noise levels of passenger trains were determined near the track of 92-91 dBA; freight trains ‒ near the track 93-92 dBA. The dependence of the noise level on the structure and condition of the plantations was determined. Thus, it can be stated that the existing forest plantations perform their phytomelioration functions and reduce the negative ingredient and parametric impact of railway transport. In order to protect the territories adjacent to the railway from pollution successfully, it is necessary to monitor transport sections constantly to ensure the sustainable development of the railway industry

Effect of the BaO-Na2_2O-Nb2_2O5_5-P2_2O5_5 glass addition on microstructure and dielectric properties of BNN ceramics

Barium sodium niobate Ba$_2$NaNb$_5$O$_{15}$ (BNN) ceramics with different amounts of BaO-Na$_2$O-Nb$_2$O$_5$-P$_2$O$_5$ (BNNP) glass were prepared via the conventional solid-state method. The effect of glass content on the structural, microstructure, and dielectric properties of BNN ceramics was investigated. The XRD results showed that no secondary phase was formed after adding BNNP glass. It was found that such additions reduce the average grain size and refine the microstructure of the obtained ceramics. Moreover, the samples exhibited a stable dielectric constant over the temperature range of 25$^\circ$C-150$^\circ$C, and their dielectric constants were significantly improved. The ceramic with 7.5 wt% BNNP glass content showed a dielectric constant which is more than twice as much as that of pure BNN ceramic, as well as a low dielectric loss of less than 5%.Comment: 5 pages, 5 figure

Structural, dielectric and electrocaloric properties of (Ba0.85Ca0.15)(Ti0.9Zr0.1-xSnx)O3 ceramics elaborated by sol-gel method

Ferroelectric ceramics (Ba0.85Ca0.15)(Ti0.9Zr0.1-xSnx)O3 (x=0.00, 0.02, 0.04, 0.06) were prepared by a sol-gel method. Structural investigation revealed the co-existence of tetragonal (P4mm) and orthorhombic (Pmm2) symmetries at room temperature for the undoped ceramic, while only a tetragonal structure (P4mm) was observed for the doped ceramics. Dielectric measurements indicate a dielectric relaxation process at high temperatures which is essentially related to the hopping of oxygen vacancies. Furthermore, a down shifting of the Curie temperature (TC) with increasing Sn4+ doping rate has been revealed. The temperature profiles of the Raman spectra unveiled the existence of polar nanoregions (PNRs) above the Curie temperature in all ceramics. The ferroelectric properties were found to be related to the microstructure. Electrocaloric effect was investigated in this system that revealed an electrocaloric responsivity of 0.225 10-6 K m/V for the composition with x = 0.04 Sn doping, where other remarkable physical properties were also observed

Raman response of quantum critical ferroelectric pb-doped srtio3

A quantum paraelectric SrTiO3 is a material situated in close proximity to a quantum critical point (QCP) of ferroelectric transition in which the critical temperature to the ferroelectric state is suppressed down to 0 K. However, the understanding of the behavior of the phase transition in the vicinity of this point remains challenging. Using the concentration x of Pb in solid solution Sr1−x Pbx TiO3 (PSTx) as a tuning parameter and applying the combination of Raman and dielectric spectroscopy methods, we approach the QCP in PSTx and study the interplay of classical and quantum phenomena in the region of criticality. We obtain the critical temperature of PSTx and the evolution of the temperature-dependent dynamical properties of the system as a function of x to reveal the mechanism of the transition. We show that the ferroelectric transition occurs gradually through the emergence of the polar nanoregions inside the non-polar tetragonal phase with their further expansion on cooling. We also study the ferroelastic cubic-to-tetragonal structural transition, occurring at higher temperatures, and show that its properties are almost concentration-independent and not affected by the quantum criticality.Fil: Linnik, Ekaterina D.. Southern Federal University; RusiaFil: Mikheykin, Alexey S.. Southern Federal University; RusiaFil: Rubi, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Constituyentes | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Constituyentes; ArgentinaFil: Shirokov, Vladimir B.. No especifíca;Fil: Mezzane, Daoud. No especifíca;Fil: Kondovych, Svitlana V.. No especifíca;Fil: Lukyanchuk, Igor A.. No especifíca;Fil: Razumnaya, Anna G.. Southern Federal University; Rusi

Comparative characteristics of the methods of delivery of chemotherapy drugs in the treatment of patients with locally advanced breast cancer: a prospective, case-series study

Centrul Oncologic Regional din Donetsk, Donetsk, Ukraina, Clinica Universitară din Odessa, Odessa, UkrainaRezumat. Introducere. Tratamentul persoanelor cu cancer de sân local-avansat este complex și constă din polichimioterapie sistemică, radioterapie, hormonoterapie și intervenție chirurgicală radicală sau paliativă. Administrarea selectivă a chimioterapeuticelor – intra-arterial, prin artera toracică internă și endolimfatic, în combinație cu cea sistemică, permite creșterea eficienței tratamentului și crește speranța la viață la 3 și la 5 ani. Material și metode. Studiu prospectiv, pe serie de cazuri, efectuat asupra la 285 de paciente cu cancer de sân local-avansat, subtipurile HER/2-neu pozitiv și basal-like, aflat în stadiile T4N0-2M0 de evoluție. Studiul a fost efectuat la Centrul Oncologic Regional din Donetsk și la Clinica Universitară din Odessa în perioada 2000-2014. Primul grup, format din 221 de paciente, a beneficiat de polichimioterapie intra-arterială (CMF, CAF, CAMF), combinată cu intravenoasă; cel de-al doilea grup, de control – de polichimioterapie endolimfatică (CMF, CAF, CAMF). Suplimentar, pacientele au primit radioterapie și terapie hormonală, la indicații, după care au fost operate. Rezultatele imediate sunt prezentate în baza criteriilor RECIST. Rezultatele tardive sunt prezentate sub formă de speranță medie la viață, precum și drept rată de supraviețuire la la 3 și la 5 ani. Rezultate. Speranța medie la viață la pacientele din lotul de cercetare a fost de 3,4 ani, iar la cele din lotul de control – de 2,8 ani. Rata de supraviețuire la 3 ani a fost de 59,9% la pacientele lotului de studiu și de 43,1% – la pacientele din lotul de control. Rata de supraviețuire la 5 ani a fost de 37,8% – la pacientele lotului de studiu și de 25,2% – la pacientele din lotul de control. Concluzii. Rezultatele tratamentului pacientelor cu cancer de sân local-avansat, cu pronostic nefavorabil al creșterii tumorale, care constă din asocierea metodei propuse de polichimioterapie selectivă intra-arterială prin artera toracică internă cu cea intravenoasă, împreună cu radioterapia și hormonoterapia, oferă rezultate mai favorabile, comparativ cu tratamentul convențional, care constă din mastectomie și polichimioterapie.Abstract. Introduction. The methods of treatment of patients with locally advanced breast cancer are complex and consist of: systemic poly-chemotherapy, radiotherapy, hormonal therapy and radical or palliative surgery. Selective administration of chemotherapy drugs – intra-arterially (through internal thoracic artery) or endo-lymphatic, in combination with systemic administration, offers a better efficiency of the treatment and rises survival rate at 3 and 5 years. Material and methods. The present study is prospective, case series based on the data of 285 patients with locally advanced forms of breast cancer HER/2-neu positive and basallike biological subtypes, with the stages T4N0-2M0. The study was performed in Donetsk Regional Antitumoral Center and University Clinic of Odessa between 2000-2014. The first investigated group included 221 patients, that underwent intraarterial poly-chemotherapy (CMF, CAF, CAMF), combined with intravenous administration; and the second, control group – endo-lymphatic poly-chemotherapy (CMF, CAF, CAMF). Additionally, patients underwent hormonal and radio therapy, upon indications, and surgery after that. Early results are presented under RECIST criteria. Late results are resented under mean life span, and survival rate at 3 and 5 years. Results. The average life expectancy of patients of the investigated group was 3.4 years, while in the control group – 2.8. Survival rate at 3 years was 59.9% in patients from the study group, and 43.1% – in patients from the control group. Survival rate at 5 years was 37.8% in patients from the study group, and 25.2% – in patients from the control group. Conclusions. Results of complex treatment of locally advanced breast cancer with unfavorable prognostic factors of tumor growth that consist of using a combination of selective intra-arterial injection and intravenous chemotherapy though the internal thoracic artery, in combination with radiation and hormonal therapy exceed the results of conventional treatment that consists of mastectomy and systemic poly-chemotherapy

Phase Diagram of a Strained Ferroelectric Nanowire

Ferroelectric materials manifest unique dielectric, ferroelastic, and piezoelectric properties. A targeted design of ferroelectrics at the nanoscale is not only of fundamental appeal but holds the highest potential for applications. Compared to two-dimensional nanostructures such as thin films and superlattices, one-dimensional ferroelectric nanowires are investigated to a much lesser extent. Here, we reveal a variety of the topological polarization states, particularly the vortex and helical chiral phases, in loaded ferroelectric nanowires, which enable us to complete the strain–temperature phase diagram of the one-dimensional ferroelectrics. These phases are of prime importance for optoelectronics and quantum communication technologie

Magnetoelectric coupling in multiferroic CFO/BCTSn core shell nanofibers elaborated by co-axial electrospinning method

Multiferroic CoFe2O4-Ba0.95Ca0.05Ti0.89Sn0.11O3 core-shell nanofibers (CFO@BCTSn NFs) were synthesized by a sol-gel co-axial electrospinning technique. The scanning electron microscope and transmission electron microscope were used to check nanofibers' core-shell structure/configuration. X-ray diffraction and a high-resolution transmission electron microscope were used to confirm the spinel structure of CFO and the perovskite structure of BCTSn. The magnetic character of the resultant CFO@BCTSn NFs was determined by SQUID magnetometry. The piezoelectricity was verified using piezo-response force microscopy, which revealed an entirely covered ferroelectric shell outline, in accordance with SEM and TEM observations. The magnetoelectric (ME) coefficient was measured as a function of the applied external DC magnetic field. The maximum ME coefficient obtained for the CFO@BCTSn NFs was 346 mV cm-1 Oe-1. The high magnetoelectric coupling suggests that CFO@BCTSn NFs could be a promising candidate for magnetic field sensor and magnetoelectric device applications