scholarly journals Water Composition Changes in the Bureiskoe Reservoir after a Landslide and Blasting

2021 ◽  
Vol 690 (1) ◽  
pp. 012023
Author(s):  
L M Kondratyeva ◽  
E M Golubeva ◽  
Z N Litvinenko
Keyword(s):  
Water Composition ◽  
Composition Changes

scholarly journals The Vasyugan Bog North-Eastern Part Hydro/chemical Regime Specific Features between the Bakchar and Iksa Rivers (Western Siberia)

2018 ◽  
Author(s):  
Keyword(s):  
Chemical Composition ◽  
Vegetation Period ◽  
Water Composition ◽  
North Eastern ◽  
Bog Waters ◽  
Bog Water ◽  
Ph Increase ◽  
Seasonal Indices ◽  
Composition Changes ◽  
North Eastern Part

Analysis of the hydro/chemical regime and spatial regularities of the water composition changes in the Vasyugan Bog North-Eastern part between the Bakchar and Iksa rivers is presented. It has been noted that the chemical composition transformation with water class, group and type during the year is a special feature of the high bog hydro/chemical regime. Within the bog limits three clusters have been identified by bog waters chemical composition characteristics on the basis of the cluster analysis. Reliable differences between the tree clusters have been determined by the mineralization amount, Са2+, Mg2+, Feобщ, NH4 +, NO3 - ions, humic and fulvene acids, Сорг and СО2 content. Analysis of the seasonal indices has demonstrated that during the vegetation period two significant maximal peaks of the bog water seasonal wave of chemical composition occur, namely in March and September. It has been noted that that the near-ground air temperature sum increase more than 10 ºС is accompanied by the pH increase in the high bog water, increase of СО2, ammonia, sulphate, iron ions, and organic matter (humic and fulvene acids, Сорг).

scholarly journals MONITORING OF ATMOSPHERIC AND SOIL WATER COMPOSITION IN FOREST ECOSYSTEMS: MILESTONES AND OUTLOOK

2021 ◽  
Vol 1 (4) ◽  
pp. 1-25
Author(s):  
V.V. Ershov ◽  
Keyword(s):  
Chemical Composition ◽  
Species Composition ◽  
Forest Ecosystems ◽  
Atmospheric Fallout ◽  
Water Composition ◽  
Long Term Trends ◽  
Industrial Regions ◽  
Composition Changes ◽  
Lysimetric Waters

The article provides an overview of Russian and foreign studies on assessment of the composition of atmospheric fallout and soil waters in forest ecosystems. The conclusion was made that little attention is given to the transformation of precipitation chemical composition by forest ecosystems, taking into account the influence of the species composition of the stand and the mosaic structure of the biogeocenosis (areas below the crowns, between the crowns, and open sites). European studies usually look at long-term development of the composition of atmospheric fallout and lysimetric waters, detecting long-term trends in composition changes of atmospheric and soil waters and identifying the factors driving these changes. In Russia, no such long-term (lasting for more than 10 years) continuous observations on the effect of man-made pollution on the composition and properties of atmospheric and soil waters were carried out. This task is very relevant for Russia and, especially, for its industrial regions.

Study of sea water chemistry changes due to thawing permafrost

2020 ◽  
Author(s):  
Maria Pogojeva ◽  
Evgeniy Yakushev ◽  
Ilya Petrov ◽  
Evgeniy Yaeski ◽  
Alexander Polukhin
Keyword(s):  
Sea Water ◽  
Chemical Properties ◽  
The Arctic ◽  
Natural Conditions ◽  
Time Intervals ◽  
Carbonate System ◽  
Water Composition ◽  
Thawing Permafrost ◽  
Permafrost Thawing ◽  
Composition Changes

<p>Influence of thawing permafrost on the chemical properties of the sea water was studied in 2 experiments organized in Svalbard in 2017 and 2018. Permafrost samples were collected at an abrasive cliff 10 km west of Longyearbyen. Experiments were focused on identifying the possible changes in concentrations of nutrients, carbonate system parameters and pollutant composition related to permafrost thawing. During the experiment, the samples of permafrost were added to the seawater. The solution was exposed to natural conditions for 24 hours in 2017 and 5 days in 2018 while water samples from the solution were taken at specified time intervals. The results of the experiment show that the sea water composition changes are connected to the permafrost thawing. Data from this experiment allowed us to estimate the total annual supply of nutrients to the Arctic from permafrost thawing by multiplying the change in concentration from this study by the annual eroded permafrost total volume in Siberia.</p><p> </p><p> </p><p> </p>

Problems in Thin-Film X-ray Quantification

1990 ◽  
Vol 48 (2) ◽  
pp. 458-459
Author(s):  
J N Chapman ◽  
W A P Nicholson
Keyword(s):  
Thin Film ◽  
Specimen Thickness ◽  
X Rays ◽  
Characteristic Peak ◽  
Local Composition ◽  
X Ray ◽  
Measured Ratio ◽  
Path Lengths ◽  
Composition Changes

Energy dispersive x-ray microanalysis (EDX) is widely used for the quantitative determination of local composition in thin film specimens. Extraction of quantitative data is usually accomplished by relating the ratio of the number of atoms of two species A and B in the volume excited by the electron beam (nA/nB) to the corresponding ratio of detected characteristic photons (NA/NB) through the use of a k-factor. This leads to an expression of the form nA/nB = kAB NA/NB where kAB is a measure of the relative efficiency with which x-rays are generated and detected from the two species.Errors in thin film x-ray quantification can arise from uncertainties in both NA/NB and kAB. In addition to the inevitable statistical errors, particularly severe problems arise in accurately determining the former if (i) mass loss occurs during spectrum acquisition so that the composition changes as irradiation proceeds, (ii) the characteristic peak from one of the minority components of interest is overlapped by the much larger peak from a majority component, (iii) the measured ratio varies significantly with specimen thickness as a result of electron channeling, or (iv) varying absorption corrections are required due to photons generated at different points having to traverse different path lengths through specimens of irregular and unknown topography on their way to the detector.

Clogging Problems in Groundwater Heat Pump Systems in Sweden

1988 ◽  
Vol 20 (3) ◽  
pp. 133-140 ◽  
Author(s):  
Annika Lindblad-Påsse
Keyword(s):  
Redox Potential ◽  
Heat Pump ◽  
Hydrogen Sulphide ◽  
Sludge Formation ◽  
Iron Bacteria ◽  
Iron Precipitation ◽  
Water Composition ◽  
Groundwater Heat Pump ◽  
And Control ◽  
System Knowledge

A number of groundwater heat pump systems have been investigated to determine the extent of problems caused by the chemistry of the groundwater used. The main purpose was to investigate sites using iron rich groundwater. Fifteen facilities were studied regularly for three years. Ten of these facilities had some kind of problem caused by iron precipitation. Four of the sites were rebuilt because of severe plugging due to iron sludge in wells, pumps and pipes. In all facilities with severe problems, iron bacteria were found. Low redox potential, indicated by hydrogen sulphide in the groundwater, seems to protect from iron bacteria. In some of the systems using groundwater with H2S the problems were corrosion and sludge formation caused by sulphur oxidizing bacteria. Rapid clogging was caused by aeration of the groundwater due to improper design of the system. Knowledge of the water composition, design of the systems to minimize aeration, and control of clogging turned out to be important factors to maintain operation safety.

scholarly journals Compensation Mechanism of the Photosynthetic Apparatus in Arabidopsis thaliana ch1 Mutants

2020 ◽  
Vol 22 (1) ◽  
pp. 221
Author(s):  
Joanna Wójtowicz ◽  
Adam K. Jagielski ◽  
Agnieszka Mostowska ◽  
Katarzyna B. Gieczewska
Keyword(s):  
Light Stress ◽  
Photosynthetic Apparatus ◽  
Protein Composition ◽  
Mrna Levels ◽  
Chlorophyll B ◽  
Low Light ◽  
Plant Acclimation ◽  
Chlorophyll B Deficiency ◽  
Composition Changes

The origin of chlorophyll b deficiency is a mutation (ch1) in chlorophyllide a oxygenase (CAO), the enzyme responsible for Chl b synthesis. Regulation of Chl b synthesis is essential for understanding the mechanism of plant acclimation to various conditions. Therefore, the main aim of this study was to find the strategy in plants for compensation of low chlorophyll content by characterizing and comparing the performance and spectral properties of the photosynthetic apparatus related to the lipid and protein composition in four selected Arabidopsis ch1 mutants and two Arabidopsis ecotypes. Mutation in different loci of the CAO gene, viz., NW41, ch1.1, ch1.2 and ch1.3, manifested itself in a distinct chlorina phenotype, pigment and photosynthetic protein composition. Changes in the CAO mRNA levels and chlorophyllide a (Chlide a) content in ecotypes and ch1 mutants indicated their significant role in the adjustment mechanism of the photosynthetic apparatus to low-light conditions. Exposure of mutants with a lower chlorophyll b content to short-term (1LL) and long-term low-light stress (10LL) enabled showing a shift in the structure of the PSI and PSII complexes via spectral analysis and the thylakoid composition studies. We demonstrated that both ecotypes, Col-1 and Ler-0, reacted to high-light (HL) conditions in a way remarkably resembling the response of ch1 mutants to normal (NL) conditions. We also presented possible ways of regulating the conversion of chlorophyll a to b depending on the type of light stress conditions.

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