Composition Of Micro Research Articles

Investigation of Pozzolan Activity, Chemical and Granulometric Composition of Micro- and Nanosilicon of the Bratsk Ferroalloy Plant

The article presents the findings of a study conducted on a range of microsilicon grades selected at the Bratsk Ferroalloy Plant. The following analytical techniques were employed: X-ray fluorescence analysis, X-ray diffraction analysis, a granulometric composition study, and pozzolanic properties. The grades of the investigated microsilicon are compared with the furnace grade and the grade of the produced ferrosilicon. The findings of the research conducted at the Bratsk Ferroalloy Plant indicate that the microsilicon produced at the facility is suitable for use as an additive in the production of tires, artificial irregularities, and other rubber products intended for use on roads. In such applications, the quality and durability of the material are determined by its ability to withstand abrasion and wear. Therefore, it is essential to utilize the purest, most amorphous, and most finely dispersed silicon dioxide. The gas cleaning device GCD-4 FeSi-75 exhibits the greatest number of these parameters among the samples presented. Different samples of microsilica have a color from white to dark gray. The chemical and granulometric compositions were determined. The pozzolan activity was investigated. Based on the conducted analyses, it is possible to draw conclusions about the properties of materials and the potential for use in the construction industry for concretes of various values. The results of the analyses indicate that silicon dioxide with GCD-4 FeSi-75 is suitable for use in critical concrete structures. The quality of the silicon dioxide with GCD-4 FeSi-75 can be compared with that of Elkem 971. It is recommended that all the studied samples be employed as modifiers for cast iron, with the GCD-4 FeSi-75 sample being the optimal choice for testing in steels. The utilization of this modifier enables a reduction in the consumption of FeSi, exerting both an alloying and modifying effect on the melt. However, it is essential to emphasize the necessity for technological selection of the method of administration, as the powder, in its pure form, is susceptible to combustion and is not readily digestible. The quality of such a modifier, with a stable guaranteed effect, is comparable to the use of FeSi. Silicon dioxide plays an essential role in the production of refractories. The primary criteria for this industry are purity, the minimum content of the crystalline phase, and the activity of the material. It is recommended that the material from GCD-4 FeSi-75 be used in the production of refractories.

Microplastics in vineyard soils: First insights from plastic-intensive viticulture systems

In the terrestrial environment, microplastics in specialty cropping systems have not been studied so far. Viticulture as a potential plastic-intensive management form and a land use with high erosion risks, plays an important role in transport and distribution of material to other terrestrial and aquatic systems. This paper is a first investigation of microplastics in vineyard soils, assessing the spatial distribution and composition of microplastics in organically and conventionally managed viticulture, and relates it to the macroplastic collected at the vineyards. Topsoils (0–10, 10–30 cm) and plastic particles on soil surfaces from eight vineyard lots were sampled. Four of the vineyards were under organic and four underconventional management and they were all located in the Moselle and Saar Wine Region (Rhineland-Palatinate, Germany). Microplastic analysis was performed via μFTIR chemical imaging after wet-chemical microplastic extraction from soil samples. The mean microplastic concentration was 4200 ± 2800 p kg−1 (mean ± SD), with detected mean sizes of 230 μm ± 300 μm. Most abundant polymers were PP (35.2 %), PA (25.3 %) and PE (15.5 %). The distribution pattern showed higher microplastic concentration in topsoil, at middle and bottom slope position. The smallest particle sizes were found in subsoil samples and bottom position. Thus, erosion is assumed to be a potential downhill transport pathway. According to our dataset, management seems to have no significant influence on microplastic abundance, but affects polymer composition. Polymer composition of micro- and macroplastics partly coincide, thus in-situ fragmentation, is considered the major input source. Based on our findings, we recommend further investigation of plastic pathways in speciality crop systems like viticulture.

Larval Frass of Hermetia illucens as Organic Fertilizer: Composition and Beneficial Effects on Different Crops.

Hermetia illucens has received a lot of attention as its larval stage can grow on organic substrates, even those that are decomposing. Black soldier fly breeding provides a variety of valuable products, including frass, a mixture of larval excrements, larval exuviae, and leftover feedstock, that can be used as a fertilizer in agriculture. Organic fertilizers, such as frass, bringing beneficial bacteria and organic materials into the soil, improves its health and fertility. This comprehensive review delves into a comparative analysis of frass derived from larvae fed on different substrates. The composition of micro- and macro-nutrients, pH levels, organic matter content, electrical conductivity, moisture levels, and the proportion of dry matter are under consideration. The effect of different feeding substrates on the presence of potentially beneficial bacteria for plant growth within the frass is also reported. A critical feature examined in this review is the post-application beneficial impacts of frass on crops, highlighting the agricultural benefits and drawbacks of introducing Hermetia illucens frass into cultivation operations. One notable feature of this review is the categorization of the crops studied into distinct groups, which is useful to simplify comparisons in future research.

Impact and survival strategies of UMKM in cakung sub-district during the covid-19 pandemic

UMKM (MSMEs) or Usaha Mikro Kecil dan Menengah (Micro, Small and Medium Enterprises) are productive business units that can be carried out by individuals or business entities in all economic sectors. UMKM have driven Indonesia's economy and development. Through UMKM, new jobs are created, there is an increase in tax revenue, an increase in GDP (Gross Domestic Product) as well as its contribution to exports and the creation of fixed capital/investment. The number of UMKM in Indonesia is 64.19 million, where the composition of micro and small enterprises is very dominant, namely 64.13 million or around 99.92 percent of the total business sector.The covid-19 pandemic has made the economy in the world, including in Indonesia, fall into a crisis. UMKM, which is usually able to survive when hit by an economic crisis, turned out to be the sector that was affected during the pandemic. The difficulties faced by UMKM players during the covid-19 pandemic are declining sales, difficulties with capitalization, obstacles to product distribution and difficulty in obtaining raw materials. During the Covid-19 pandemic, there were restrictions on activities so that UMKM players had to carry out the right strategy to continue to do business in this situation. E-commerce is carried out to continue to serve consumers and also so that the business being managed can survive. In addition to e-commerce, innovating makes business people or business actors, including UMKM,still able to survive during the Covid-19 pandemic. The government provides support incentives for UMKM through the National Economic Recovery (PEN) program in 2020 and continued in 2021.The purpose of this study was to determine the impact of the covid-19 pandemic on the businesses of UMKM Cakung players, and to determine the effect of e-commerce, innovation, government policies on the survival position of UMKM Cakung. The sample of this study was 35 UMKM Cakung players who were randomly selected. Data analysis was carried out descriptively and by regression and correlation. The results showed that the covid-19 pandemic had an impact on the businesses of UMKM Cakung players. E-commerce and innovation partially have no effect on the survival position of UMKM Cakung, but government policies affect the survival position of UMKM Cakung . Simultaneously, e-commerce, innovation and government policies have an influence on the survival position of UMKM Cakung.

Interfacial properties of liquid metal immersed in various liquids

HypothesisWhen gallium-based liquid metal (LM) droplets are injected through different solvent media, the oxygen solubility of the environment influences the droplet eccentricity. The formation of an oxide membrane in solvents can determine whether a bulk-scale droplet behaves in a liquidlike or solidlike manner. In the case of LM emulsions, the solvent’s oxygen solubility leads to varying degrees of organic solvent adsorption. The adsorption of solvent molecules changes the surface energy of the oxide layer. ExperimentsThe pinch-off frames of LM droplets immersed in liquids with differing oxygen solubility were captured using a high-speed camera. Through scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), the surface composition of micro and nanoscale LM emulsions in different solvents was investigated. The van Oss-Good model was implemented to determine the polar and nonpolar surface energy components of LM layers with adsorbates. FindingsPear-shaped LM droplets displaying solidlike behavior are created when the mole fraction of dissolved oxygen in the ambient solution is above approximately 2.43×10-4. For LM emulsions sonicated in organic solvents, Carbon/Oxygen (C/O) and Carbon/Gallium (C/Ga) atomic percent ratios display an increasing trend with increasing oxygen solubility. The nonpolar component of surface energy shows a logarithmic relationship with the oxygen solubility of the solvent used to treat the LM layer. The polar component of surface energy is more susceptible to the chemical properties of the solvent.

Monthly Succession of Biofouling Communities and Corresponding Inter-Taxa Associations in the North- and South-West of the Arabian Gulf

Marine biofouling is a complicated process involving changes within micro- and macro-fouling community, species co-occurrence, and inter-taxa association patterns. An investigation of all above-mentioned aspects has rarely been conducted so far. Our study aimed to compare the monthly succession of the biofouling community developed at two locations each in the north- (Kuwait) and south-west (Oman) of the Arabian Gulf (AG) over 6 months, and to explore the association patterns within microfouling and between micro- and macro-fouling communities on a temporal and spatial scale. Spatio-temporal effects on the abundance and composition of micro- and macro-fouling communities were detected based on total biomass, bacterial and phototroph abundances, macrofouling coverage and 16S rRNA gene sequencing. We documented the development of distinct ecological niches within the fouling community resulting in fundamentally different succession patterns depending on location. Network analysis revealed nine clusters of highly interconnected co-occurring fouling bacterial taxa (M1-M9), with strong association (both positive and negative) to microalgae and macrofoulers in both Kuwait and Oman. Early stages of Kuwait biofilm showed M7 (cyanobacterial OTUs) positively and negatively associated with the majority of diatoms and macroalgae (Cladophoraceae), respectively, unlike the later stages where M5 (composed of Vibrio spp.) was positively associated with polychaetes (Hydroides elegans). While the causal relationships behind the observed inter-taxa associations remain unknown, our study provided insights into the underlying dynamics of biofouling processes encountered in the north- and south-west of the AG. Comprehensive future investigations encompassing transcriptomic or metabolomic tools may be required to address the challenge of interpreting such complicated dynamics over time and space in a continuously changing environment.

Epibiont Assemblages on Nesting Hawksbill Turtles Show Site-Specificity in the Persian Gulf

Sea turtle epibionts can provide insights into the hosts' habitat use. However, at present, there is a lack of information on sea turtle epibiont communities in many locations worldwide. Here, we describe the epibiont communities of 46 hawksbill turtles (Eretmochelys imbricata) in the Persian Gulf. Specifically, we sampled 28 turtles from the Dayyer-Nakhiloo National Park (DNNP) in the northern Gulf and 18 turtles from Shibderaz beach in the Strait of Hormuz. A total of 54 macro, meio, and micro-epibiont taxa were identified, including 46 taxa from Shibderaz and 29 taxa from DNNP. The barnacles Chelonibia testudinaria and Platylepas hexastylos, as well as harpacticoid copepods and Rotaliid foraminifers, had the highest frequency of occurrence found on almost all turtle individuals. Harpacticoids were the most abundant epizoic taxa (19.55 ± 3.9 ind. per 9 cm2) followed by forams (Quinqueloculina spp.: 6.25 ± 1.5 ind. per 9 cm2 and Rotaliids: 6.02 ± 1.3 ind. per 9 cm2). Our results showed significant differences between the study sites in the composition of micro and macro-epibiont communities found on hawksbill turtles. We speculate that the differences in epibiont communities were largely influenced by local environmental conditions.

The Potential of Small Grains Crops in Enhancing Biofortification Breeding Strategies for Human Health Benefit

Nutrition is a source of energy, and building material for the human organism. The quality of food has an effect on the quality of individual life. Minerals and vitamins participate in various catalytic and regulatory functions of the main metabolic processes: absorption, transport, redox and biosynthesis of organic compounds, genetic information transfer, etc. Regular consumption of dietary fibers like β-glucans and oat-specific phenolics, antioxidants, and avenanthramides, stimulate innate and acquired immunity, prevent cancer, obesity, reduce glucose, total cholesterol and triglyceride blood levels and regulate the expression of cholesterol-related genes. Thus, all those compounds are vitally important for the normal functional status of the human body. A deficiency in one or another essential nutrient causes disruptions in human metabolism, thus leading to serious illnesses. Plants are the main source of essential nutrients that are bioavailable for humans. One of the most popular groups of staple crops are the small grains crops (SGC), so these crops are most often used for biofortification purposes. Exploiting the potential of plant resources, biofortification is a long-term strategy, aimed at increasing the number of essential micro- and macronutrients in major food sources and ensuring their bioavailability. The most productive way to implement such strategy is the active use of the possibilities offered by collections of plant genetic resources, including SGC, concentrated in various countries of the world. The collections of plant resources contain both cultivated plants and their wild relatives that possess the required composition of micro- and macronutrients. A complex scientific approach to studying plant germplasm collections, together with agricultural practices (soil enrichment with fertilizers with a required composition), genetic biofortification (traditional breeding, marker-assisted selection or genetic engineering tactics), and their combinations will lead to the development of new biofortified cultivars and improvement of old ones, which can be used to solve the problems of unbalanced nutrition (malnutrition or hidden hunger) in different regions of the world.

Microelements in the Late Pleistocene ice wedges of Seyakha yedoma, east of Yamal Peninsula

The subject of this research is the composition of micro- and macro- rare earth elements in the Late Pleistocene syngenetic ice wedges of the Seyakha yedoma, explored in the outcrop of the Gulf of Ob in the east of Yamal Peninsula (70°9'27.88 "N, 72° 34'8.31" E), north of the Western Siberia. The All-Russian Scientific-research Institution of Mineral Resources after named N.M. Fedorovsky examined the composition of chemical elements in the ice wedges using the methods of atomic-emission spectrometry and mass spectrometry with inductively linked plasma (spectrometers Elan-6100, Optima-4300DV, Perkin-Elmer, Polyvac E-1000, Rank Hilger). The following conclusions were made: 1) Ice wedges of the Seyakha yedoma are rich in macro - and microelements was recorded, which exceeds such in ice wedges of Yakutia by 8-10 times. The high composition of microelements indicates the role of aerosol and soil particles in the formation of chemical composition of ice. The differences between the ice of Yamal and Northeastern Yakutia also testify that the chemical composition reflects the involvement of marine aerosols in ice formation. 2) Rare-earth elements accumulate in the ice of Seyakha yedoma. The composition of all rare-earth elements exceeds the Clarke number in river waters by 69 (Tm ) – 382 (Y) times. 3) Variability of microelement composition within the ice wedge is insignificant, which implies that the water of the polluted with dust and aerosols spring-summer snow is filtered through the entire snow layer and is partially cleaned prior to getting into the ice-break in the ground under the snow.

The impact of the weakly-fibrogenic bauxite dust on lungs in mine workers

Introduction. New cases of pneumoconiosis are detected annually at the bauxite mining enterprises of the Sverdlovsk Region. Differential diagnosis of bauxite pneumoconiosis with other interstitial lung diseases using only lung radiography can be difficult. The aim of the work was to clarify the nature of changes in the lungs of workers exposed to weakly fibrogenic dust of bauxite, and the relationship of changes in the lungs with working conditions in cases of difficulty in making the final diagnosis of pneumoconiosis. Material and methods. Underground miners of a working face and underground drifters with a work experience of at least ten years in conditions of exposure to bauxite dust were examined. All patients underwent a plain chest x-ray and high-resolution computed tomography (HRCT), bodyplethysmography, bronchoscopic examination with trans-bronchial biopsy, and subsequent histological examination of the biopsy. To determine the elemental composition of micro- and nanoparticles in biological tissue samples, scanning electron microscopy with X-ray spectral microanalysis was used. Results. During the histopathological examination of lung tissue biopsy materials by a bright-field method and polarized filter and using electron microscopy, the composition of dust in the lung tissue complied with the composition of industrial aerosol. It is formed during bauxite mining (aluminum, iron, and quartz compounds). High-resolution computed tomography (HRCT) and bronchoscopy can detect signs of exposure to industrial aerosol of complex composition represented by early interstitial parenchymal fibrosis and changes in bronchial mucosa. This is typical for individuals at risk of occupational respiratory diseases development without radiological features specific to pneumoconiosis. Before X-ray pattern formation, typical for pneumoconiosis, bronchitis syndrome and atrophic changes in the bronchial mucosa are developed. This happens in workers exposed to weakly-fibrogenic dust of a complex composition formed during the mining of bauxite. The changes are permanently observed long after the exposure to the dust factor has ceased.

Natural Surface Hydrocarbons and Soil Faunal Biodiversity: A Bioremediation Perspective

Hydrocarbon pollution threatens aquatic and terrestrial ecosystems globally, but soil fauna in oil-polluted soils has been insufficiently studied. In this research, soil hydrocarbon toxicity was investigated in two natural oil seepage soils in Val D’Agri (Italy) using two different approaches: (i) toxicological tests with Folsomia candida (Collembola) and Eisenia fetida (Oligochaeta) and (ii) analysis of abundance and composition of micro- and meso-fauna. Soil sampling was done along 20 m-transepts starting from the natural oil seepages. Toxicological testing revealed that no exemplars of F. candida survived, whereas specimens of E. fetida not only survived but also increased in weight in soils with higher PAH concentrations, although no reproduction was observed. Analysis on microfauna showed that Nematoda was the most abundant group, with distance from seepages not affecting its abundance. Arthropoda results showed that Acarina, Collembola and Diptera larvae represented the most abundant taxa. The highest divergence in community composition was found between soils situated near seepages and at 5 m and 10 m distance. Arthropoda taxa numbers, total abundance and Acarina were lower in soils with high PAH concentration, while Diptera larvae were not significantly affected. Earthworms, together with Nematoda and Diptera larvae, could therefore represent ideal candidates in PAH degradation studies.

Mesoporous polymer systems based on divinylbenzene copolymers modified with linear rubbers

Porous polymer systems based on divinylbenzene copolymers modified with co-monomers (ethylvinylbenzene, methyl acrylate, methacrylic acid) and linear rubber macromolecules (polybutadiene, polyisoprene, polyisobutylene, polystyrene-butadiene, polyacrylonitrile-butadiene) were investigated. The copolymers in the form of spherical beads were synthesized by radical suspension polymerization of monomer compositions with appropriate porogenic organic solvents. It was found that modification of the divinylbenzene copolymers by linear rubbers enables the synthesis of sorbents with a controlled fractional composition of micro- and mesopores. A universal method is suggested for a quantitative estimation of fractional pore size distribution in the range of micro and mesopores from the data of low-temperature nitrogen sorption. Calculations of integral and differential distributions are based on using methods of quenched solid density functional theory (QSDFT), non-local density functional theory and the Barrett-Joyner-Halenda method based on capillary condensation theory. According to QSDFT calculations, the porous system of sorbents contains three groups of pores of certain sizes: 1.7–3.3, 3.3–6.6 and 8.4–40 nm. Upon introduction of polyisoprene into the polymer system the sorbent containing primarily 8–24 nm mesopores is obtained; upon the introduction of polyisobutylene, the sorbent with pore sizes of 4–6 nm is synthesized. The volume and surface area of micropores in the copolymers with polyisoprene and polyisobutylene may be increased by extracting a part of the rubber phase with toluene. Specific surface area of the copolymers varies in the range of 230–570 m2 g−1. Scanning electron microscopy studies of the porous structure of the polymer systems showed that in the copolymers with polybutadiene the porous structure is formed by the aggregates of globules 20–60 nm. The copolymer with polyisobutylene has a 3D skeletal structure with 100–200 nm voids.

Analysis of high-temperature flexural behaviour of copper–alumina micro- and nanocomposites

Copper (Cu)-based composites were studied for their high-temperature mechanical response. Copper is a high temperature–high strength material when combined with harder reinforcements, which find applications in engine components. High-temperature flexural testing of copper–alumina (Al2O3) micro- and nanocomposites fabricated by powder metallurgy was carried out at temperatures of 100 and 250°C. The composition of micro- and nanocomposites varied as 5, 10 and 20 vol.% and 1, 3 and 5 vol.%, respectively. The variation in the flexural strength of the composites at high-temperature testing is reported and compared with the ambient test values here, and, subsequently, deformation mechanisms of the composites are discussed. Fractography was performed to predict the mode of failure. The ductile mode of failure in microcomposites is contradictory to quasicleavage in nanocomposites. Nanocomposites show higher flexural strength at 100°C compared to microcounterparts. Interfacial de-cohesion and particle pull out are the results of the thermal gradient across the matrix to the reinforcement.

Spatially Resolved XPS Characterization of Electrochemical Surfaces

Synchrotron-based scanning photoelectron microscopy (SPEM) has opened unique opportunities for exploiting processes occurring at surfaces and interfaces, which control the properties of materials for electrochemical devices, where issues of chemical and morphological complexity at microscopic length scales should be faced and understood. The present article aims to demonstrate the present capabilities of SPEM to explore the surface composition of micro- and nano-structured materials, focusing on cases relevant to electrochemical technologies. We report and discuss a selection of recent results about three different systems, targeting hot topics in the fields of electrochemical energy storage and electrochemical fabrication: (i) an in-depth analysis of Ag-In electrodeposited alloys exhibiting dynamic pattern formation, (ii) the analysis of electrochemical processes at the electrodes of a self-driven solid oxide fuel cell and (iii) an operando characterization of a single-chamber solid oxide fuel cell. The last example has been performed at near-ambient pressure conditions using a unique specially designed setup which extends the traditional capabilities of scanning photoemission microscopes in the ultra-high and high-vacuum regimes to operating conditions that are closer to realistic ones, contributing to overcome the so-called “pressure gap”.

USE OF CORN GRAIN IN PRODUCTION OF FOOD PRODUCTS

In Ukraine, the following basic crops are used as raw materials for the production of cereals, flour, flakes: wheat, barley, buckwheat, oats, corn, rice, millet, peas. The volume of world grain production in recent years has grown significantly. In Ukraine, corn is the main fodder crop, and only in small quantities is used as food. Corn takes the leading place among the main grain crops in the world agricultural production. The production of corn for grain is concentrated in warm regions. In some regions, corn is the basis of the traditional food of the population, but mostly it is part of the feed in the feeding of farm animals. Corn does not accumulate nitrates and is an environmentally friendly product. Corn is a plant of versatile use. Currently, corn is one of the most important food crop cultivated by man. As to the largest producers of this cereal are the United States, China, Mexico, India, Brazil, Argentina, Indonesia, South Africa, France and Italy. Today, about 3500 food and technological products are made from corn. Corn is able to largely meet the needs of animal husbandry, its share is almost 30% in the composition of concentrated feed. Corn is used in food, starch, brewing and alcohol industries. With the advent of new directions in the development of biotechnology in the world, the importance of this culture is growing even more. In the countries of the European Union in recent years, the production of various types of fuels from plant materials - biodiesel, bioethanol, biomethanol and biofuel is actively developing. Bioethanol is obtained from all cultures with a high content of starch and sugar, for example, potatoes, sugar beet, corn, various types of cereals, and therefore a significant expansion of the acreage under corn is projected. In the article volumes of corn grain collection in different years in Ukraine for the production of cereals and groats are considered. Various types of maize as a perspective raw material for use in the food industry are considered. It is shown that two subspecies of maize are most widespread in Ukraine - a dentate (large grain of elongated form) and siliceous (a rounded grain). The presence of vitamins B (B1, B2, PP), calcium, magnesium, phosphorus and iron, as well as trace elements (copper, nickel, etc.) in maize makes it possible to recommend corn products as a separate product or in combination with other people with blood diseases, allergies, diabetes mellitus, obesity and other forms of metabolic disorders and pathology of the gastrointestinal tract. The authors analyzed the chemical composition of corn grain of various botanical groups intended for the production of cereals and products from them. The composition of micro- and macronutrients of corn groats used in the production of food products (snacks, breakfast cereals, instant cereals, cereals, etc.) is given.

Chemical diagenesis in near-surface zone above oil fields in geochemical exploration

Hydrocarbon microseepages result in chemical and mineralogical changes in the near-surface zone above oil reservoirs. The results of geochemical research within the three oil fields of the West Siberian Basin demonstrate that chemical diagenetic processes lead to an increased inhomogeneity in chemical element distribution in soils, subsoil atmosphere and snow. Pulse cathodoluminescence (PCL) study of soils and transmission electron microscopy (TEM) study of micro- and nanoparticles, collected from the subsoil atmosphere, showed that geochemical conditions over oil reservoirs were favorable for the enrichment of silicate and aluminosilicate minerals by chemical impurities. Chemical composition of micro- and nanoparticles of metal compounds, collected from within the vertical projection of the oil field outline, suggested that these compounds were formed under intense reductive conditions that are not characteristic for the hypergene zone.

Дослідження мінерального складу сланей пармелії перлинової

Introduction. Parmelia perlata is a widespread lichen that belongs to the Parmeliaceae family. In Ayurvedic medicine thalli of Parmelia perlata are used for the treatment of a series of diseases of different genesis. Literature data contain information that the representatives of Parmeliaceae family show a wide spectrum of biological activity, in particular, possess anti-bacterial, cardiotonic, spasmolytic, antioxidant and other types of activity.The aim of the study – to learn the mineral composition of parmelia perlata thalli of Kazakh and Russian production.Materials and Methods. For the study of the composition of micro- and macroelements by the atomic-absorption spectroscopy method Parmelia perlata thalli of Kazakh and Russian production were used.Results and Discussion. As a result of the study the content of 19 mineral elements in Parmelia perlata thalli of Kazakh and Russian production was determined. The dominating elements in both studied objects were calcium and silicon. The content of calcium in the raw material of Kazakh production comprised 2270.00 μg/100 g, and in the raw material of Russian production – 1938.00 μg/100 g. The content of silicon in the raw materials studied comprised 1815.00 μg/100 g and 1619.00 μg/100 g respectively. The content of iron and magnesium in both samples was almost identical, while the content of sodium and potassium in the raw material of Russian production was 1.5 times higher than in the raw material of Kazakh production. Both samples were found to accumulate magnesium and zinc in quite high concentration. The content of heavy metals in both raw material samples was within the limit of maximum permissible concentration for medicinal plant material and food products according to the requirements of the current legislation.Conclusions. The obtained results can be used at working out medicines on the basis of Parmelia perlata thalli and the quality control methods for the raw material.

Formation, Phase, and Elemental Composition of Micro- and Nano-Dimensional Particles of the Fe–Ti System

X-ray fluorescence, X-ray phase analysis, and transmission Mossbauer and NGR spectrometry are used to study the formation, phase, and elemental composition of Fe–Ti particles. The interaction between Fe(III) ions and dispersed titanium in an aqueous solution containing chloride ions and HF is studied. It is shown that the resulting Fe–Ti samples are a set of core–shell microparticles with titanium cores coated with micro- and nanosized α-Fe nucleation centers with the thinness outer layer of iron(III) oxide characterized by a developed surface.

Planktonic Diatoms Species Composition and Water Characteristics Along Selected Sites of River Kisat, Kisumu County, Kenya

In all global aquatic ecosystems, species composition of micro and macro organisms, abundance, growth, development and their distribution depend on quantity of contaminants, types of contamination; levels of chemical concentrations; sediment load; electrical conductivity; turbidity; seasonal variations; depth, width, flow rate, number of inlets and outlets with volume of water and also the impacts of anthropogenic activities always reflect on the water quality of a wetland. Physico-chemical parameters and planktonic diatoms species composition were studied at five selected sampling stations (C1-C5) along River Kisat from March to August 2016. There are 26 species of planktonic diatoms belong to 13 genus which are Amphora, Aulacoseira, Cyclotella, Cymbella, Diatoma, Fragillaria, Gomphocymbella, Navicula, Nitzschia, Pinnularia, Stephomodiscus Surillela and Synedra. Out of these 26 species, only eight species (Cymbella cistula; Cymbella sp; Diatoma hiemiale; Navicula granatum; Nitzschia lucastris; Nitzschia palea; Nitzchia recta and Nitzschia sub-acicularis) are present in all the five sampling stations, while Fragillaria longissima and Gomphocymbella beccari are present only once in sampling station C4 and C5 respectively. Only genus Nitzschia has five species followed by the genus Aulacoseira represented by three species. There are seven genus which are Amphora, Cyclotella, Cymbella, Diatoma, Fragillaria, Navicula and Synedra represented by two species each, while rest of the four genus including Pinnularia, Gomphocymbella, Surillella and Stephomodiscus are represented only with one species each. The mean monthly values of selected physico-chemical parameters are: electrical conductivity 657.27 ± 186.78 μS/cm, temperature 24.84 ± 0.65°C, pH 7.87 ± 0.24, dissolved oxygen 4.19 ± 0.7 mg/l, turbidity 89.90 ± 9.76 NTU, flow rate 1.38 ± 0.05 km/h; total alkalinity 150.85 ± 28.23 mg/l, total nitrogen 657.27 ± 227.56 μg/l, total phosphorus 677.18 ± 20.87 μg/l, silicates 4.11 ± 0.52 mg/l and chlorophyll-a 130.54 ± 40.15 mg/l. The study revealed that only pH, dissolved oxygen, alkalinity and silicate show significant difference (p ≤ 0.05) along Kisat river but rest of the physico-chemical levels of conductivity, turbidity, total nitrogen, total phosphorus show higher concentrations in river water. It is concluded that the presence or absence of planktonic species and their frequency should be used as bioindicator( s) to assess the status of water quality of any aquatic ecosystem.

The vertical distribution and abundance of copepod nauplii and other micro- and mesozooplankton in the seasonal ice zone of Lützow-Holm Bay during austral summer 2009

The Antarctic seasonal ice zone (SIZ) is an ecologically important region of the Southern Ocean. However, the abundance and vertical distribution of micro- and mesozooplankton in this zone, in particular the contribution of nauplii of smaller copepod taxa, are poorly understood. We investigated the vertical distribution, abundance, and species composition of micro- and mesozooplankton in the SIZ of Lutzow-Holm Bay, East Antarctica, in January 2009. Zooplankton samples were collected using a 60-µm mesh closing net (appropriate to estimate the quantitative abundance of copepod nauplii) vertically hauled from three depth layers (0–100, 100–200, 200–500 m). Small calanoid copepods, Oithonidae, and Oncaeidae were dominant among the zooplankton communities in this region. Cluster analysis revealed that the communities were separated by depth into epipelagic (0–200 m) and mesopelagic (>200 m) groups. Distribution patterns in the 0- to 100-m layer changed at the sea ice edge, but showed no clear relationship with frontal structures. Nauplii of copepods including Oithona spp., Oncaea spp., and Calanoida were major contributors to total zooplankton abundance. The abundance of these nauplii in the surface layer was high in open water and the marginal ice zone but low in the pack ice zone where chlorophyll a concentrations were high. Low water temperature associated with sea ice, rather than food availability, may have caused the low copepod nauplii abundance observed in the surface layer within the pack ice zone. These findings provide valuable background information to monitor variations in zooplankton community structure in response to changing environmental conditions.