Elemental Chemical Composition Research Articles

Multi-element ferroactive materials based on KNN-PZT compositions with fundamentally different physical properties

Quasibinary section solid solutions of a four-component system of the (1-x)(Na0.5K0.5)NbO3-xPb(Ti0.5Zr0.5)O3 composition, based on compositions with fundamentally different physical responses (Na, K)NbO3(KNN), Pb(Ti, Zr)O3 (PZT), have been produced by two-step solid-phase synthesis followed by sintering using conventional ceramic technology. The features of their structural formation have been revealed, a phase diagram of equilibria has been constructed, correlation relationships composition ‒ structure ‒ microstructure ‒ macroproperties have been established. Based on the measured X-ray fluorescence intensities, the concentrations of chemical elements, included in the surface composition of the samples of piezoceramic materials, have been determined. Statistical characteristics and variations in the chemical composition of the structure-forming chemical elements of the ferroactive composite materials were researched. Micro-XRF combined with methods of mathematical statistics provides to characterize a degree of chemical homogeneity and statistically compare the average concentrations of the chemical elements. Changes in atomic concentrations were revealed as result of varying technological conditions of synthesis. We have carried out the X-ray quantitative analysis for the thickness of surface layer corresponding to the chemical elements at the depth yield of X-ray fluorescence. Three groups of solid solutions ‒ the foundations of intelligent materials have been identified: with high Kp, ε33T/ε0 low V1E (near PZT) – promising for low-frequency applications; with low ε33T/ε0, high V1E (near KNN) ‒ for high-frequency use; with intermediate values of the piezoelectric parameters (near SS1→SS2 ‒ transition), intended for operation in combined equipment complexes.

Elucidating the structure and optimising the photoluminescence properties of Sr2Al3O6F: Eu3+ oxyfluorides for cool white-LEDs

Herein, Sr2Al3O6F in hexagonal symmetry was synthesized via a solid-state methodology. The X-ray diffraction pattern of Sr2Al3O6F was refined by the Rietveld refinement with lattice parameters a = 17.8232(1) Å and c = 7.2168(0) Å. The stability of the crystal structure is further confirmed from the results of bond valence sums and the global instability index. The theoretical calculations of the electronic and optical behaviors of the Sr2Al3O6F were analyzed by density functional theory and the obtained results of the lattice parameters and direct bandgap were found close to the experimental data. The chemical states and elemental composition of Sr2Al3O6F were also authenticated by X-ray photoelectron spectroscopy (XPS). To evaluate the suitability of the Sr2Al3O6F structure as high efficient red phosphor, a series of Eu3+ doped Sr2-xEuxAl3O6F (x = 0.0 to 0.10) were synthesized, which showed intense red-orange emission (5D0→7F1,2) at UV and blue excitations. The photoluminescence intensity corresponding to 5D0→7F2 transition decreased significantly for x = 0.10 due to the luminescence quenching. Nevertheless, further enhancement in photoluminescence of Sr1.9Al3O6F: Eu0.1 sample was realized with the substitution of 0.1 mol Ba2+ ion for 0.1 mol Sr2+ ion. The various radiative properties of the emission bands were also analyzed through the Judd-Ofelt theory. The optimized Sr1.8Al3O6F: Ba0.1/Eu0.1 phosphor showed high red color purity (>95%), and moderate thermal stability of around 72% at 150 °C, suggesting that it could be an ideal red component for white-LEDs. A white-LED comprising the commercial yellow phosphor and the optimized sample showed bright white light having the CRI of 80.5%, CCT of 5510 K, and CIE of (0.33, 0.36) indicating that Sr1.8Al3O6F: Ba0.1/Eu0.1 phosphor is an appropriate red component for cool white-LEDs.

ГОДОВЫЕ КОЛЬЦА СОСНЫ ОБЫКНОВЕННОЙ (PINUS SYLVESTRIS L.) – ИНДИКАТОР ГЕОХИМИЧЕСКОЙ ОБСТАНОВКИ И ХРОНОЛОГИЧЕСКОГО ИЗМЕНЕНИЯ ХИМИЧЕСКОГО ЭЛЕМЕНТНОГО СОСТАВА ОКРУЖАЮЩЕЙ СРЕДЫ

Актуальность исследования обусловлена необходимостью поиска или изобретения точного и информативного индикатора для проведения экологического мониторинга окружающей среды. Цель: изучить особенности накопления 28 химических элементов в годовых кольцах сосны обыкновенной (Pinus sylvestris L.) различных территорий. Объект: годовые кольца сосны обыкновенной (Pinus sylvestris L). Методы: отбор кернов сосны обыкновенной; высушивание и разделение проб на временные интервалы, измельчение кернов; определение содержания 28 химических элементов методом количественного инструментального нейтронно-активационного анализа; обработка данных статистическими методами. Результаты. Определен химический элементный состав образцов годовых колец сосны обыкновенной (Pinus sylvestris L.), отобранных на территориях трех регионов России: Томской области, Кемеровской области и Республики Бурятия. Сравнение химического элементного состава годовых колец деревьев разных регионов помогло увидеть геохимические особенности каждой территории в отдельности. Специфичными для дерева Томской области являются элементы Ba (3 мг/кг), Rb (0,5 мг/кг), Ce (0,02 мг/кг), Cs (0,01 мг/кг) и другие. Для дерева Кемеровской области: Cr (1 мг/кг), Fe (34 мг/кг), As (0,01 мг/кг), Sb (0,002 мг/кг), La (0,01 мг/кг), U (0,004 мг/кг) и другие. Для дерева из Республики Бурятия: Br (1 мг/кг), Sr (7 мг/кг), Ag (0,04 мг/кг), Au (0,001 мг/кг), Th (0,001 мг/кг) и другие. Таким образом, дендрогеохимический метод исследования может быть использован для оценки геохимической обстановки территории по уровню накопления химических элементов в годовых кольцах дерева. Динамики поступления химических элементов в годовые кольца позволяют изучать историю трансформации химического элементного состава окружающей среды. Так, тренды железа и хрома для Pinus sylvestris Кемеровской области ярко отражают развитие черной металлургии, а тренды As, Ag, Cs, Sb, U, Sm, Th и Br – развитие угольной промышленности региона. Тренды щелочных металлов Rb, Cs, радиоактивного U и редкоземельных элементов Nd, Sm, Eu показали интенсивность воздействия в разные промежутки времени предприятий ядерно-топливного цикла и других предполагаемых источников на окружающую среду Томского района Томской области. Сделан вывод, что дендрогеохимический мониторинг может быть использован в целях исследования локальных и глобальных изменений окружающей среды и позволяет восстанавливать историю прошлого загрязнения.

Structural/Chemical Characterization and Bond Strength of a New Self-Adhesive Bulk-fill Restorative.

The material structure and chemical elemental composition of a new self-adhesive composite hybrid were investigated. The bonding performance when applied on flat (FLAT) vs high C-factor class-I cavity-bottom (CAVITY) dentin and in light-cure (LC) vs self-cure (SC) mode was determined. The self-adhesive bulk-fill composite Surefil One (Su-O; Dentsply Sirona) was compared with the resin-modified glass-ionomer Fuji II LC Improved (Fuji2LC; GC) and the ion-releasing alkasite material Cention N (CentionN; Ivoclar Vivadent). The material structure was examined with SEM and TEM, while the chemical elemental composition was analyzed using EDS. The immediate and aged microtensile bond strength (μTBS) of Su-O_LC/SC was compared to that of Fuji2LC applied without any pre-treatment, and to that of CentionN applied following bonding with Adhese Universal (AU) (Ivoclar Vivadent) in self-etch mode (AU/CentionN). All restorative materials were bonded onto FLAT and CAVITY dentin. Statistical analysis was performed with the Kruskal-Wallis nonparametric test. EDS analysis revealed that Su-O was richer in C and P than the reference restorative materials. Applied to FLAT dentin, the significantly highest immediate and aged μTBS were recorded for AU/CentionN, which were not significantly different only from Su-O_LC. Applied to CAVITY dentin, the significantly highest immediate μTBS was recorded for AU/CentionN, which did not differ significantly only from Su-O_SC. Su-O_LC bonded to CAVITY dentin suffered from a high incidence of pre-test failures. While Su-O_LC bonded effectively and durably to FLAT dentin, Su-O_SC bonded more favorably than Su-O_LC in class-I cavities, which was probably related to shrinkage stress variously challenging the respective bond.

Color stability and Microstructure Changes of Two Pressable Ceramics after Repeated Firing protocols

Statement of the problem: it is important that researchers gather more information regarding the effect of repeated firing on optical properties and microstructure of all ceramic restorationPurpose: The aim of this in vitro study was to investigate the effect of repeated firing on color stability and microstructure changes using X-ray diffraction, EDAX and SEM of two pressable ceramics.Methods: A total number of forty eight freshly extracted maxillary central incisors were collected. The selected teeth were cleaned and disinfected in 0.5% sodium hypochlorite solution, then stored in distilled water for maximum two weeks until the testing began. The roots of the selected teeth were serrated with a disc for retention. The teeth were mounted vertically into auto-polymerizing acrylic resin material. Full coverage all-ceramic preparation was performed for all teeth. The prepared teeth were randomly divided into two equal test groups (n=24) according to the all-ceramic materials used for crown fabrication as follows: Group I: IPS e-max Press (LD): Twenty four prepared teeth were restored with pressable lithium di-silicate glass ceramics (IPS e.max press, Ivoclar, Vivadent AG, Schann, Lieshtenstein). Group II: Celtra Press (ZL): Twenty four prepared teeth were restored with pressable zirconia-reinforced lithium di-silicate glass ceramics (Celtra Press, Dentsply, Sirona.). Then samples were subjected to repeated firing cycles up to five firing cycles. Samples were divided into four equal subgroups (n= 6), according to the number of firing cycles performed for each sample. Subgroup (A) : Control samples, subgroup (B):1st firing cycle ,subgroup (C): 3rd firing cycle, Subgroup (D): 5th firing cycle. All ceramic crowns fabrication was done according to manufacturer instructions for each material. For each crown the L *, a* and b* was measured using spectrophotometer (Vita Easy shade) by placing the probe tip on the central part of the labial surface of the crown, the colorimetric values of ΔL*, Δ a* and Δb* were measured from differences in the respective L*, a*and b* values. The total color difference ΔE* were measured at each firing cycles subgroups for each group of ceramic materials. Data were collected, tabulated and statistically analyzed. Microstructural analysis for the two tested all ceramic materials was examined by X-ray diffractometer, scanning electron microscopy, the elemental chemical composition as well as quantitative analysis was measured by energy dispersive X -ray spectroscopy (EDAX) .This analysis was done after the control firing and the 5th firing cycle. Results: Regardless of the ceramic material, statistically significant color differences were resulted by repeated firing as follows ; perceptible but yet clinically acceptable for lithium di-silicate glass ceramics (LD), whereas, perceptible and clinically unacceptable for zirconia reinforced lithium di-silicate(ZL). The microstructure of the two pressable ceramic materials (LD, ZL) turned out to be unstable after repeated firing cycles for both ceramic materials.Conclusions: Color stability is affected by repeated firing for both tested materials. Repeated firing is not recommended for ziconia reinforced lithium di-silicate because color changes (ΔE = 4.18) are exceeding the clinical acceptability.Repeated firings might result in microstructral changes within the ceramic materials.Microstructure analysis through SEM, EDAX and XRD is a reliable analytical approach.

Elemental chemical composition and As speciation in rice varieties selected for biofortification

Toxic elements, essential elements and other elements were determined in Brazilian rice by inductively coupled plasma-mass spectrometry (ICP-MS). A method for As speciation using hydride generation was developed and applied in rice samples.

Impact of the coastal taiga fires onto chemical elemental composition of soils, grounds and near-shore waters of Bol shoy Ushkaniy Island (Lake Baikal, Siberia)

In order to study the chemicals drainage into the lake near-shore zone from burnt out forest territories by ICP-MS method, we determined elemental composition of soils from forest territories in the shore zone on Bolshoy Ushkaniy Island, which were damaged by the fire, which were not damaged by the fire, of ash from burnt anthills, of grounds and water of near-shore zone adjacent to sites of burnt forest and of forest site, which was not burnt (background one). The research found out that the shore zone with damaged by fire vegetation and soil cover and burnt anthills, compared to background site, is a more abundant source of mobile chemical compounds, especially of P, S, K, Ca, Mn, Zn, Mo, Cd, Ba. Their considerable part with surface flow and interflow migrate out of soil profile, accumulate temporarily in the base of shore scarp and are transferred gradually into the adjacent to the shore scarp zone of splash and further, into the lake shallow water zone.

Identification the areas of concern for pine forest and soil cover conditions in the Predbaikalie region

The article summarizes and analyzes monitoring results for Scots pine (Pinus sylvestris L.) forests of Southern Predbaikalie (Eastern Siberia, Russia) exposed to technogenic pollution and high recreational loads. The surveys were carried out in areas adjacent to large industrial centers and in recreational areas of the National Park Pribaikalsky. It is shown that vital state of treestands weakened by industrial exposure is comparable to forest health in areas with high recreational loads. The results show that in terms of contamination levels the most problematic areas are those which are adjacent to Shelekhovsky, Irkutsky, Usolsky and Angarsky industrial centers; as for recreation impact, its unacceptably high levels were found in the vicinity of Listvyanka and Khuzhir villages as well as in many sections of the Circum-Baikal Railway. In these areas, the values of the vital state index (VSI) and the soil resistance potential (SRP) index were the lowest, amounting to 3.2-4.4 points for pine stands VSI and 4.7 points for SRP near Khuzhir and 4.8 points for SRP near Usolsky industrial center, while in the background areas, both the VSI and SRP values were close to 10 points. Based on the obtained results, we have developed a schematic map of the problem areas of the Southern Predbaikalie. The data were also used to create a relational database on the elemental chemical composition of pine needles, including those in technologically polluted parts of the region.

Study and identification of contaminant phases in commercial activated carbons

This work aims to identify and study contaminant phases present in commercial activated carbons (AC), also to determine the quality of the AC through methylene blue absorption. A straightforward methodology was implemented to carry out a complete characterization of AC that consists of the morphology determination by SEM, an elemental chemical composition by XRF, identification of crystalline phases using XRD, and vibrational analysis through FTIR. The results showed that the primary contamination in AC is related to trace elements present in raw materials as well as residues from the activation process such as Mg, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, As, Sr, and Zr. It was observed that these elements could react during all steps of AC fabrication and form crystalline compounds, mainly calcium carbonates, calcium phosphates, and silicon oxides. Moreover, gas adsorption (BET) and methylene blue (MB) removal probes show that there is no correlation between the surface area and the MB removal capability.

Improving the Curing and Mechanical Properties of Short Carbon Fibers/Epoxy Composites by Grafting Nano ZIF‐8 on Fibers

AbstractThe nano metal–organic framework particles (nano ZIF‐8) are grafted onto the surface of short carbon fibers (SCFs) by a facile in situ growth method in order to functionalize SCFs. The morphology, crystal structure, and chemical element composition of modified SCFs (ZIF‐8@SCFs) are investigated. The grafted nano‐ZIF‐8 could remarkably enhance the roughness, polarity, and wettability of SCFs surface and promote the curing reaction of epoxy composites. The tensile strength, flexural strength, elastic modulus, toughness, and impact strength of the epoxy composites with 1 wt% ZIF‐8@SCFs are increased by 25%, 31%, 51%, 28%, and 42% compared to that of the composites with 1 wt% SCFs, respectively. Furthermore, the storage modulus (E′) and glass transition temperature (Tg) are enhanced from 2558 MPa and 108.2 °C to 3000 MPa and 147.6 °C. The significant improvement in mechanical and thermomechanical properties of the prepared composites could be ascribed to the ameliorated wettability, enhanced mechanical interlock, and increased chemical bonding induced by ZIF‐8@SCFs.

Kaunas Castle from Another Perspective: the Chemical Composition of Iron Construction Elements

The chemical composition of iron construction elements is not usually a topic of interest in Medieval archaeology. This article focuses attention on the chemical composition of iron elements such as nails. For compositional analysis, the XRF method was used. A comparison was made between XRF results and physical measurements. The aim of this article was to identify the amount of iron in metal elements that were possibly used in constructing castles, and to find a connection between the chemical composition of objects and their physical measurements.

Influence of Constructional-Material Parameters on the Fire Properties of Electric Cables

The significant number of cables of different materials and construction used extensively in building objects increases their fire load and, therefore, strongly influences safety in the case of fire. The purpose of the study was to identify relevant factors related to the construction of electrical cables, and perform a qualitative and quantitative assessment of their influence on specific fire properties, such as heat release and smoke production. Fifteen cables of different construction and materials were studied using the EN 50399 standard test. The analysis was focused on cable constructional-material parameters related to the chemical composition of non-metallic elements and the number and shape of conductors in the cable, as well as the concentric barrier as armor or the copper concentric conductor. The conclusions drawn from the experiments were: (1) Construction, the number of conductors, and the presence of armor or concentric metallic conductors improve the fire properties by forming a barrier against flame penetration through the cable; (2) the use of copper conductors resulted in a decrease of fire parameters compared to cables with aluminum conductors (peakHRRav parameter even four times lower for copper cable); (3) construction material based on non-plasticized poly(vinyl chloride) (PVC) significantly reduced the fire properties of cables more than halogen-free materials (LS0H) (peakHRRav parameter more than 17 times higher for the fully halogenated cable), which is due to the decomposition process of the material; and (4) no clear relationship between the fire parameters and the cable parameter, χ, was found.

Composition of chemical elements in the edible viscera of Tibetan pigs and its correlation with environment and feed.

The main purpose of this research was to evaluate the element distribution in the edible viscera of Tibetan pigs and to clarify its correlation with soils, drinking water and feed. A total of 55 chemical elements were simultaneously quantified. P, K, Na, Mg, Ca, Fe and Zn were the most abundant elements in the analyzed viscera. The general distribution of all element concentrations in the viscera of Tibetan pigs was such that liver>kidney>small intestine>heart=lung=large intestine>stomach. Comparison with national and international allowable limits of toxic elements indicates that consumption of Tibetan pig viscera presents potential health risks. Spearman correlation analysis reveals that significantly (p<0.0001) positive relationships exist between the element profiles of viscera and drinking water, soils as well as feed. For all edible viscera, the largest values of correlation coefficient were observed to be with corn feed. Our research provides a relatively comprehensive investigation of the elemental composition in Tibetan pig viscera. The correlation data would be helpful for the local farm to reformulate the feed for Tibetan pigs to improve the quality and safety of the viscera.

Superhydrophobic Cerium-Based Coatings on Al-Mg Alloys and Aluminized Steel

Aluminum-magnesium (Al-Mg) alloy and aluminum-coated steel (aluminized steel) are typically used for the manufacturing of baking trays and molds. For these applications, these materials must be modified to develop release and hydrophobic properties. With this aim, the bare substrates are typically coated with low-surface energy materials such as fluoropolymers, elastomers, or sol-gel layers. In this work, some alternative strategies to prepare these functional surfaces are presented. We used three-step processes involving (i) micro-texturing, (ii) nano layer deposition through immersion and electrodeposition, and (iii) hydrophobization. The raw substrates were sanded or sandblasted at the micro scale, accordingly. Texturization at the nano scale was achieved with a cerium layer formed by electrodeposition or solution immersion. The cerium layers were hydrophobized with fatty acids. The wetting properties of the samples were studied with tilting-plate and bouncing drop methods. We measured the surface roughness of the samples by contact profiling and analyzed their surface morphology using a field emission scanning electron microscope (FESEM). The elemental chemical composition of the samples was analyzed by energy-dispersive X-ray spectroscopy (EDX). The wettability results indicated that the best performance for the Al-Mg substrates was reached by sandblasting and later immersion in a cerium nitrate solution. For aluminized steel substrates, the best results were obtained with both electrodeposition and immersion methods using a cerium chloride solution.

ELECTRON PROBE MICROANALYSIS OF CARBONACEOUS ROCKS

The problems that often arise during the X-ray analysis of light elements are caused by the physics of the X-ray spectrum process and the mathematical algorithms (correction systems) used to calculate the concentration of elements. Therefore, the solution to these problems is determined by the hardware implementation of the analysis methods and its functionality. The most difficult situations arise in the qualitative and quantitative analysis of rocks that contain carbon in their composition. This is due to the fact that in the zone of generation of the X-ray signal, the polymerization of residual oil vapors and the appearance of a carbon film on the surface of the sample under study occurs. Therefore, with the standard method of studying a sample of unknown composition using an energy dispersive spectrometer, the peak of carbon is usually excluded from the scheme for calculating the concentrations of elements, which is unacceptable for carbon-containing samples. Using the example of the study of calcium and strontium carbonates, we have developed a method for measuring elemental chemical composition using the INCA Energy+ X-ray analysis system, which includes energy dispersive and wave dispersive spectrometers. The X-ray spectrum analysis system was applied in the study of carbon-containing unstable samples under the electron probe – unique remnants of paleoflora in the impact-melted rocks of the impact crater Elgygytgyn.Ref

Green synthesis of SnO2-bentonite nanocomposites for the efficient photodegradation of methylene blue and eriochrome black-T

In this paper, for the first time, SnO2-bentonite nanocomposites were synthesized through immobilization of SnO2 nanoparticles on natural bentonite using aqueous extract of jujube fruit. In this simple and safe procedure, the jujube acted as a naturally-sourced reducing agent. The biosynthesized SnO2-bentonite nanocomposites were characterized by various techniques such as SEM (scanning electron microscopes), EDX (energy-dispersive X-ray spectroscopy), TEM (transmission electron microscope), XRD (X-ray diffraction), FT-IR (Fourier-transform infrared spectroscopy), and N2 adsorption-desorption to investigate the morphology, chemical elemental composition, crystalline size, functional groups and surface area of the biosynthesized nanocomposites. The supported SnO2 nanoparticles on bentonite were observed obviously in the SEM image of SnO2-bentonite nanocomposites. The EDX analysis of biosynthesized nanocomposites was well indicated the successful immobilization of SnO2 nanoparticles on bentonite. The average particle size of SnO2-bentonite nanocomposites was evaluated based on the TEM and found to be 18 nm. The crystalline nature of the SnO2-bentonite nanocomposites was confirmed via XRD analysis. The presented functional groups in biosynthesized SnO2-bentonite nanocomposites were identified by FTIR spectral analysis. Afterward, then, the photocatalytic performance of SnO2-bentonite nanocomposites was studied for the efficient degradation of organic dyes (methylene blue and eriochrome black-T) without using any toxic reducing agents under solar irradiation. The new SnO2-bentonite nanocomposites as a very stable catalyst could be tolerated the reaction conditions and reused at least three times without remarkable loss of activity.

Hydrolysis kinetic study of CaAlSiN3:Eu2+ red phosphor with both water immersion test and first-principles calculation

At present, most high-power white Light-emitting diode and laser diode (LED&LD) package is usually constructed by a blue LED&LD chip with a Cerium doped Yttrium Aluminum Garnet (YAG:Ce3+) yellow phosphor, but its color rendering performance is severely challenged due to the lack of red light emission spectrum. The CaAlSiN3:Eu2+ red phosphor can effectively improve the color quality of traditional yellow phosphor converted white LED&LDs(pc-wLED&LDs), however, it is often susceptible to degradation under high temperature and high humidity environments, which will directly affect the color quality of pc-wLED&LDs. In this study, a series of water immersion tests on CaAlSiN3:Eu2+ red phosphor are used to quantitatively study its hydrolysis reaction kinetics. Then, the degradations of its photoluminescence and photothermal performances are evaluated by characterizing the crystal structure, micromorphology and chemical element composition. Finally, an atomic level hydrolysis reaction mechanism of CaAlSiN3:Eu2+ red phosphor is investigated by using the first-principles density functional theory (DFT) calculation. The results show that: (1) By modelling the in-situ monitored electrical conductivity of CaAlSiN3:Eu2+ red phosphor water solution with a first-order reaction function, the calculated hydrolysis reaction rate satisfies the Arrhenius relationship and the reaction activation energy is estimated as 49.19 kJ/mol; (2) The increased self-heating effect of CaAlSiN3:Eu2+ red phosphor after water immersion test attribute to its drastic drop of light emission efficiency; (3) The hydrolysis reaction mechanism of CaAlSiN3:Eu2+ red phosphor is confirmed, which sequentially results in the dissolution of Ca2+ and OH−, the crash of host lattice and the accumulation of reaction residues.

Phase Composition of D16 and V95 Deformable Aluminum Alloys with the Quantitative Assessment of Metal Burning at Various Stages of Development

New methods to monitor metal burning in D16 and V95 aluminum alloys based on using energy-dispersive X-ray spectral analysis (EDS analysis) are shown. It is known that the reduced properties of aluminum-based materials are often associated with the presence of metal burning in the structure. The structural changes caused by metal burning (partial melting of eutectics and excessive low-melting phases with the subsequent crystallization of molten microvolumes) are often accompanied by the development of porosity and negatively affect the physicochemical, mechanical, and manufacturing properties. The ability to reveal metal burning at early stages makes it possible to reject the defective metal. The characteristics sensitive to the early metal-burning stage are proposed based on the EDS analysis. The induced metal-burning degree in a sheet of the D16 alloy is identified. The structural components of the V95 alloy determining the alloy liability to metal burning are established. It is shown that the EDS analysis makes it possible to reveal the variations in the chemical composition of structural elements of the D16 and V95 aluminum alloys, as well as quantitatively identify the metal-burning stage by the oxygen content. The metal-burning development leads not only to an increase in the oxygen content in the chemical composition of aluminum alloys, but also to a decrease in the electrical conductivity of the material. The correlation between the electrical conductivity of the D16 alloy with induced metal burning and oxygen content is considered. The applicability of the EDS analysis is due to the simplicity of the procedure and the possibility of quantitatively evaluating the development of defects in heat-strengthened deformed aluminum alloys after manufacturing heating. It can be used as an additional method for investigation when metallographic analysis gives an ambiguous answer when revealing early metal-burning stages.

Anatomical characterization, histochemistry and crystal analysis of the leaf blade of Mangifera indica L.

Mangifera indica L., popularly known as mangueira, is an important fruitful widely used in Brazilian traditional medicine for the treatment of diabetes, anemia, diarrhea, hemorrhoids, indigestion, asthma, bronchitis, flu, hypertension, rheumatism, disorders of the liver and for tumors. In order to expand the pharmacobotanical information about the species, this study aimed to perform the anatomical characterization, histochemistry and crystal analysis of the leaf blade of M. indica. For the anatomical characterization were used optical microscopy, polarization microscopy and scanning electron microscopy. Histochemical tests were performed to evidence the presence of metabolites and microchemical analyzes by dispersive energy spectroscopy were done to determine the elemental chemical composition of the crystals. The microscopic analysis allowed the identification of characters useful in the identification of the species, such as the presence of glandular trichomes in the leaf blade. Through histochemistry was evidenced the presence of phenolic compounds, lipophilic substances, lignin and starch in the leaf blade. The chemical nature of the crystals was determined to be calcium oxalate. The results contribute to the pharmacobotanical standardization of M. indica.

Сравнительный анализ элементного химического состава побегов Padus avium из техногенно нарушенных экотопов

In order to use vegetative resources more efficiently nowadays a possibility to produce food supplements enriched with biologically active substances and also combined types of medical plant raw materials from wood pulp of crown is considered. When using plants growing on anthropogenically transformed territories, the issues of accumulation of chemical elements (CE) potentially hazardous for human in them become decisive. There have been studied mechanisms of CE distribution in Padus avium fruits, leaves and stems from anthropogenically transformed ecotopes in the south of Western Siberia. The content of CE has been studied by the atomic emission spectrometry after dry ashing. Element chemical composition of soils of studied habitats is characterized by high variability and absence of significantdifferences. The amounts of CE in fruits, leaves and lignified stems of Padus avium from anthropogenically transformed ecotopes with the different degree of environmental footprint do not differ significantly. Relatively stable content of CE is mainly peculiar to the essential elements of Ca, K, Mg, P, B, Cu, Zn and Pb, Sn, V as well. High variability is recorded for CE strongly associated with finely dispersed soil particles (Al, Cr, Fe, Mn, Na, Sc, Si, Ti). Higher concentration of Sr specific to other plants in the south of Western Siberia is observed in all studied samples. A sustainable difference was recorded in CE’s concentration in the studied organs. The minimum percentage of the most part of the elements was found in fruits (apart from B) and stems (apart from Zn). Leaves contain several times more CE whichmay be due to a higher contribution of soil particles. The exceedence absence of maximum permissible concentrations of potentially hazardous CE and presence of biologically active compounds in fruits and leaves indicate the capability of usage crown wood pulp of P. avium in food and beauty industries as a source of biologically active substances and natural dyes.For citation: Zagurskaya Yu.V., Siromlya Т.I. Comparative Analysis of the Elemental Chemical Composition of Padus avium Shoots from Antropogenically Disturbed Ecotops. Lesnoy Zhurnal [Forestry Journal], 2019, no. 5, pp. 105–114. DOI: 10.17238/issn0536-1036.2019.5.105Funding: The research was carried out within the framework of the projects No. 0352-2019-0015 (EGISU NIOKTR No. 171170414100531) and No. 0313-2016-0001 (EGISUNIOKTR No. 171170301100781).