scholarly journals Mineral Composition of Sapropelles of Lakes of the Right Bank of the Ob River (Middle Ob Region)

2019 ◽  
Vol 9 (1) ◽  
pp. 77
Author(s):  
M. P. Sartakov ◽  
E. M. Osnitsky ◽  
K. Iu. Kudrin ◽  
N. S. Larina

The objective of this work is to study the mineral composition of bottom sediments of eight small lakes located on the right bank of the Ob River (Western Siberia) in the Surgut region of the Khanty-Mansiysk Autonomous Okrug - Yugra. The studies were carried out using wave dispersive X-ray fluorescence (WDFR) spectroscopy. The content of organic substances, ash, and oxides in the ash in the samples was determined. Based on these data, the studied bottom sediments were classified. The bottom sediments of Lake S-1 are siltstone sands, lakes Vach Lor and S-189 - weakly sapropelic siltstone sands, lakes S-5, S-6, S-3, S-89, and S-294 - typical sapropels. The article presents the content of the main elements in the ash of the studied samples.

Minerals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 552
Author(s):  
Ekaterina Ovdina ◽  
Vera Strakhovenko ◽  
Emilia Solotchina

We studied 46 small, drainless lakes in various landscape types: The sub-taiga (Vasyugan plain), forest–steppe (Baraba lowland), and steppe and subzone of ribbon forests (Kulunda plain). Sampling of lake components (sediments, water, and biota) was performed. The materials were analyzed via a combination of modern analytical methods (atomic absorption spectroscopy, X-ray fluorescence, scanning electron microscopy and X-ray diffractometry). It was found that in the south of Western Siberia, lakes with a bicarbonate-sodium water composition are widespread against the background of general landscape zoning. This composition contributes to the abundant growth of biota in the lakes, which leads to the processes of authigenic carbonate formation from calcite–dolomite series and aragonite on geochemical barriers, i.e., drifting biota–water, submerged biota–water, and water–bottom sediments against a background of terrigenous demolition and organic matter accumulation. The article shows the differences in the composition and structure of low-temperature carbonate minerals formed on various geochemical barriers. It was found that low-magnesium calcite and aragonite are the most common authigenic carbonates in small lakes in the south of Western Siberia and are formed on all three geochemical barriers in lakes. High-magnesium calcites and Ca-excess dolomites are formed only at the water–bottom sediment barrier in lakes with HCO3–Na and Cl–HCO3–Na water composition at pH > 9 and with a total dissolved solids > 3 g·L−1 (in some lakes of HCO3-Na composition with a TDS < 3 g·L−1 and pH > 9).


2021 ◽  
Vol 6 (4) ◽  
pp. 299-307
Author(s):  
Gulnara N. Shigabaeva ◽  
Andrey V. Soromotin ◽  
Еvgeny V. Galunin ◽  
Аnna V. Ruseikina ◽  
Anna А. Kurbash ◽  
...  

The article analyzes and provides data on the processes of accumulation of heavy metals by bottom sediments from the point of view of environmental assessment. The purpose of this paper is to identify the degree of anthropogenic influence on the lakes of the Tazovskiy and Surgut districts, and assess the ecological state of water bodies and adjacent territories. The main processes occurring in natural reservoirs, which lead to the transfer of toxicants into the environment, are considered. The data of quantitative chemical analysis of bottom sediments of two groups of natural reservoirs with an assessment of their ecological state according to the results of statistical processing of the measured values were obtained. Excess concentrations of metals were recorded: for mobile forms – 2200 times for Fe, 1050 times for Mn, 35 times for Cr, 20 times for Co, up to 15 times for Ni, 5 times for Cu, 3 times for Pb, for acid-soluble forms – 45 000 times for Fe, 550 times for Pb, up to 75 times for Ni, 525 times for Mn, 105 times for Cr, 50 times for Cu, 16 times for Co. The geochemical interpretation of the results of the factor analysis is presented.


Author(s):  
Roman V. Smelyi ◽  
Alexander L. Finkelshtein ◽  
Igor S. Yakimov ◽  
Alena A. Amosova ◽  
Victor M. Chubarov

A method is proposed for estimating the range of mineral group content in the cores of silicate bottom sediments of lakes based on the search for the minimum and maximum content of stoichiometric minals that make up the group of minerals, provided that the balance of the mineral composition and the content of elements in the sample is observed. The mineral components were determined using the method of qualitative X-ray phase analysis, the contents of the main rock-forming elements were determined by X-ray fluorescence analysis. Comparison with the results of quantitative X-ray phase analysis showed that the contents of mineral groups either lie in the range calculated in the extreme search procedure based on data on the element composition, or overlap with the calculated range within the measurement error. The systematic discrepancy between the results of calculating the range of content of the silicon dioxide phase and the results of quantitative X-ray phase determination of quartz observed for the samples under consideration is due to the presence of an X-ray amorphous phase of biogenic silica. The proposed method for estimating the range of mineral group content is easy to implement, uses the publicly available MS Excel software, and can be useful for estimating variations in mineral composition by core depth, in conditions of frequent shortages of individual sample material distributed between different methods of analysis


2020 ◽  
Vol 169 ◽  
pp. 01001
Author(s):  
Elena Agbalyan ◽  
Aleksander Krasnenko ◽  
Elena Shinkaruk

We performed this study in order to obtain relevant data about the actual ecological status of the lakes in remote areas of the Russian Arctic. The objective was to determine the level of technogenic pollution of bottom sediments in the lakes on the Vilkitsky island in the Kara Sea. To this end, we examined 8 of the island’s small lakes. The content of heavy metals and metalloids (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Y, Nb) in the samples of bottom sediments was determined using the method of Energy Dispersive X-ray Fluorescence (EDXRF). The total pollution value in the examined bottom sediments varied from Zc = 9.5 to Zc = 15.3. The maximum level of pollution was found in Lake 4 located in an anthropogenically disturbed area due to the levels of Cr, Co, Ni, As, Y, Nb.


Author(s):  
Roman V. Smelyy ◽  
Ekaterina V. Kaneva ◽  
Anastasiya V. Oshchepkova ◽  
Valerii A. Bychinskii ◽  
Tat’yana S. Aisueva ◽  
...  

The paper reports comparison of three approaches to define the contents of minerals and mineral groups in the carbonate-silicate lake bottom sediments. The two approaches are based on the method of X-ray powder diffraction. The first one treats with the Rietveld Method in the software DIFFRAC Plus diffractometer D8 Advance (PDF-2 database). The second one uses the method of reference intensities (corundum ratios) and optimization of the model powder patterns from the X-ray phase standards of PDF-2 database and equations of the element balance with regularization of the least square functional. The third approach of physic-chemical modeling selects probable single mineral and multi-component phases through modelling the sold solutions, and it uses the data on the element composition obtained by XRF technique, as well as the data of X-ray diffraction on the qualitative mineral composition. Thirty samples of bottom sediment cores taken in the Zun-Torey Lake in East Siberia were analyzed by the three approaches described herein. The contents of mineral groups (feldspars, quartz, clay minerals and carbonates) varied within the range 10-40 mass %. The discrepancies between obtained results show the standard deviation ranging from 2 to 9 mass %. A relative standard deviation commonly provides the value below 30 %, so such determinations could be considered quantitative ones. With regard to the acquired data, it is hard to prefer this or that approach. Available data was employed to assess the error of X-ray phase powder analysis in measuring the abundance of mineral groups in the carbonate-silicate sedimentary rocks in the absence of reference materials to compare with certified mineral composition


2007 ◽  
Vol 1 (1-2) ◽  
pp. 75-80 ◽  
Author(s):  
Snezana Petrovic ◽  
Vojo Jovanov ◽  
Slavica Vujovic ◽  
Jonjaua Ranogajec ◽  
Emilija Fidancevska

Conservation and restoration of cultural heritage are the objects of great interest worldwide. For setting the correct methodology for the procedures of the restoration it is very important to have the right information about the state of the object and the characteristics of the original materials. The basis of our examinations were clay products (samples of bricks, terracotta and clay roof tile) from the middle ages, the fortress in Bac. The following methods were used: x-ray diffraction, classic chemical analysis, SEM-EDS, Hg-porosimetry and dilatometry. Based on the used methods, mineral composition, temperature and regime of firing and textural properties of the examined materials were determined. The degree of destruction of examined materials was also identified, in order to find compatible materials for future techniques of conservation and restoration.


Author(s):  
S. Edith Taylor ◽  
Patrick Echlin ◽  
May McKoon ◽  
Thomas L. Hayes

Low temperature x-ray microanalysis (LTXM) of solid biological materials has been documented for Lemna minor L. root tips. This discussion will be limited to a demonstration of LTXM for measuring relative elemental distributions of P,S,Cl and K species within whole cells of tobacco leaves.Mature Wisconsin-38 tobacco was grown in the greenhouse at the University of California, Berkeley and picked daily from the mid-stalk position (leaf #9). The tissue was excised from the right of the mid rib and rapidly frozen in liquid nitrogen slush. It was then placed into an Amray biochamber and maintained at 103K. Fracture faces of the tissue were prepared and carbon-coated in the biochamber. The prepared sample was transferred from the biochamber to the Amray 1000A SEM equipped with a cold stage to maintain low temperatures at 103K. Analyses were performed using a tungsten source with accelerating voltages of 17.5 to 20 KV and beam currents from 1-2nA.


2004 ◽  
Vol 6 (2) ◽  
pp. 186-198
Author(s):  
G. K. Khursevich ◽  
A. V. Kudelskiy ◽  
S. A. Fedenya ◽  
J. Marphy

2008 ◽  
pp. 68-75 ◽  
Author(s):  
G. S. Taran

In the Ob river floodplain between the mouths of its tributaries Vakh and Tym (within the limits of Aleksandrovskiy district of Tomsk region), phytocoenoses belonging to 9 associations and 2 communities of Braun-Blanquet classification vegetation classes are listed. Class Lemnetea is represented by associations Ricciocarpetum natantis (Segal 1963) Tx. 1974, Lemnetum trisulcae Soó 1927, Stratiotetum aloidis Miljan 1933; class Potametea is done by asso­ciations Potametum perfoliati Koch 1926, Myriophylletum sibirici Taran 1998, Myriophylletum verticillati Soó 1927, Potametum graminei Koch 1926, Potametum pectinati Carstensen 1955, Nymphoidetum peltatae (All. 1922) Bellot 1951, as well as Sagittaria natans and Potamogeton natans—Ceratophyllum demersum communities. The syntaxa distribution in Western Siberia and adjoining territories is characterized.


2019 ◽  
Vol 65 (5) ◽  
pp. 756-759
Author(s):  
Mikhail Postolov ◽  
Nadezhda Kovalenko ◽  
K. Babina ◽  
Stanislav Panin ◽  
Yelena Levchenko ◽  
...  

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal neoplasm characterized by expression of both mela-nocytic and smooth muscle markers. Only 10 primary malignant lung PEComas have been reported up to date. We report a 59-year-old male who presented with a lung neoplasm, found during the routine X-ray examination. Preoperative CT-scan revealed the 3,5-cm-sized mass, located at the border of the upper, middle and lower lobes of the right lung. Patient underwent a thoracotomy, resection of the upper, middle and lower lobes of the right lung accompanied with mediastinal lymphadenectomy. After surgery, chylothorax was revealed. Conservative treatment was unsuccessful, so we performed laparoscopic clipping of the thoracic lymph duct. Patient was dismissed from hospital on the 10-th day after the second operation in good condition. In this report, we intend to increase the limited knowledge relating to natural history and optimal treatment of such a rare condition as a primary malignant lung PEComa.


Sign in / Sign up

Export Citation Format

Share Document