scholarly journals Organic matter and mineralization of river waters in mountains of Russia and adjacent countries

2019 ◽  
pp. 99-106
Author(s):  
M. P. Smirnov
Keyword(s):  
Organic Matter ◽  
Experimental Studies ◽  
The Arctic ◽  
Mountain Rivers ◽  
River Waters ◽  
Taiga Forest ◽  
Salinity Water ◽  
Cis Countries ◽  
Relationship Of ◽  
The Relationship

The article examines general regularities of the formation of dissolved organic matter (DOM), salinity (∑), the acid-alkaline indicators (pH) river waters in the mountains with various types of altitudinal zonation in Russia and CIS countries. The analysis is based on the results of many years of experimental studies in the network of the Roshydromet. The reaction of water of rivers in a southerly direction in accordance with changes in landscape-geochemical conditions are sequentially changed from acidic in the tundra of the Arctic to neutral in the tundra and taiga, slightly alkaline in forest-meadow and alkaline in a desert and subtropical mountains. The average annual salinity water of the mountain rivers in two Northern types of vertical zones is 42 and 74 mg/l, in two Southern types – 140 and 450 mg/l. The average annual values of permanganate (PO) and bichromate (BO) oxidation, and color of river water in xerophytic desert-subtropical mountains are small (3 and 7), and increase to medium and slightly increased grades into humid tundra and taiga, tundra of the Arctic, and the forest meadow mountains (7–8 and 13–18 mg O/l). Relationships PO:BO change from 62% in the tundra of the Arctic up to 50%, 41% and 35% in the tundra and taiga, forest-meadow and desert-subtropical mountains. The content of humic (HA) and fulvic (FA) acids is also maximum in two Northern types of vertical zones (0.224 and 1.80 mg/l) and decreases in the two Southern types to 0.013 and 0.067, 0.373 and 0.637 mg/l. The relationship of contents of HA and FA decreases to the South in forest-grassland and desert-subtropical mountains in 1.3 and 3.7 times.

scholarly journals Fractionation of Heavy Metals in Multi-Contaminated Soil Treated with Biochar Using the Sequential Extraction Procedure

Biomolecules ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 448
Author(s):  
Mahrous Awad ◽  
Zhongzhen Liu ◽  
Milan Skalicky ◽  
Eldessoky S. Dessoky ◽  
Marian Brestic ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Ph ◽  
Contaminated Soil ◽  
Contaminated Soils ◽  
Extraction Procedure ◽  
Sequential Fractionation ◽  
Relationship Of ◽  
The Relationship

Heavy metals (HMs) toxicity represents a global problem depending on the soil environment’s geochemical forms. Biochar addition safely reduces HMs mobile forms, thus, reducing their toxicity to plants. While several studies have shown that biochar could significantly stabilize HMs in contaminated soils, the study of the relationship of soil properties to potential mechanisms still needs further clarification; hence the importance of assessing a naturally contaminated soil amended, in this case with Paulownia biochar (PB) and Bamboo biochar (BB) to fractionate Pb, Cd, Zn, and Cu using short sequential fractionation plans. The relationship of soil pH and organic matter and its effect on the redistribution of these metals were estimated. The results indicated that the acid-soluble metals decreased while the fraction bound to organic matter increased compared to untreated pots. The increase in the organic matter metal-bound was mostly at the expense of the decrease in the acid extractable and Fe/Mn bound ones. The highest application of PB increased the organically bound fraction of Pb, Cd, Zn, and Cu (62, 61, 34, and 61%, respectively), while the BB increased them (61, 49, 42, and 22%, respectively) over the control. Meanwhile, Fe/Mn oxides bound represents the large portion associated with zinc and copper. Concerning soil organic matter (SOM) and soil pH, as potential tools to reduce the risk of the target metals, a significant positive correlation was observed with acid-soluble extractable metal, while a negative correlation was obtained with organic matter-bound metal. The principal component analysis (PCA) shows that the total variance represents 89.7% for the TCPL-extractable and HMs forms and their relation to pH and SOM, which confirms the positive effect of the pH and SOM under PB and BB treatments on reducing the risk of the studied metals. The mobility and bioavailability of these metals and their geochemical forms widely varied according to pH, soil organic matter, biochar types, and application rates. As an environmentally friendly and economical material, biochar emphasizes its importance as a tool that makes the soil more suitable for safe cultivation in the short term and its long-term sustainability. This study proves that it reduces the mobility of HMs, their environmental risks and contributes to food safety. It also confirms that performing more controlled experiments, such as a pot, is a disciplined and effective way to assess the suitability of different types of biochar as soil modifications to restore HMs contaminated soil via controlling the mobilization of these minerals.

Application of Galvanic Zinc-Iron Coating in the Repair of Transport and Technological Machines

2021 ◽  
Vol 1022 ◽  
pp. 181-193
Author(s):  
Dmitry M. Rozhkov ◽  
Evgenia V. Eltoshkina ◽  
Petr I. Ilyin ◽  
Olga A. Svirbutovich
Keyword(s):  
Experimental Studies ◽  
Iron Alloy ◽  
Resource Saving ◽  
Experimental Base ◽  
Optimal Resource ◽  
Iron Coating ◽  
Saving Mode ◽  
Relationship Of ◽  
The Relationship ◽  
Kinetics Of

The article presents the results of experimental studies to determine the relationship between the electrolysis modes and the properties of electroplating coatings for mathematical modeling of the dynamics of the electrolytic process (MDEP), described by a system of ordinary differential equations due to the complex relationship of the kinetics of chemical reactions, hydrodynamics and mass transfer in the electrolyte flow, the kinematics of electrode plates, and the influence of the electric field of the "anode-cathode" pair on all these processes. At the same time, the experimental base was a series of full-scale experiments to restore the seats of the root supports of cylinder blocks with electroplated coatings. The final result of the research is the procedure for constructing an optimal resource-saving mode of electroplating, which is a zinc-iron alloy.

scholarly journals Issues of wind mode visualization and pedestrian comfort assessment when designing residential buildings on sloping territories in the Arctic zone

2019 ◽  
Vol 64 ◽  
pp. 03013 ◽  
Author(s):  
Ilya V. Dunichkin ◽  
Emanuele Naboni ◽  
Anna E. Korobeinikova ◽  
Olga I. Poddaeva
Keyword(s):  
Urban Areas ◽  
Residential Buildings ◽  
The Arctic ◽  
Wind Regime ◽  
Local Climate ◽  
Factors Affecting ◽  
Aerodynamic Roughness ◽  
The Stability ◽  
Relationship Of ◽  
The Relationship

Subject of research: visualization of the wind regime of residential buildings on the slope area in the Arctic. Goals: the purpose of the study is to identify the problems of visualization of the wind regime on the slopes and the analysis of patterns of airflow around the sloping territories, affecting the comfort of pedestrians. Materials and methods: airflow patterns of slope areas with different characteristics and comfort assessment for humans are analyzed in the course of work. Geotechnical methods are presented in solving the problems of wind erosion and the stability of hillsides and complex terrain within the city limits. Results: The importance and novelty of the research in studying the relationship of slope geometry and environmental quality, as a decrease in comfort inevitably leads to a decrease in the development of nearby urban areas in settlements on the coast of the Arctic Ocean, problems with climate and local climate, as well as a decrease in the quality of life of people. The article considers the relationship of plastic relief with the aeration regime of the territory, the dependence of aerodynamic roughness on their height, features of aeration of the slope and hilly terrain, factors affecting the direction and speed of the wind and methods for studying the aeration regime of slope areas. Findings: The possibilities of applying existing approaches to research and visualization for slope areas are demonstrated. The direction of development of the technique for visualization of slope areas has been determined.

Measuring change

2015 ◽  
Author(s):  
David L. Streiner ◽  
Geoffrey R. Norman ◽  
John Cairney
Keyword(s):  
Experimental Studies ◽  
Curve Analysis ◽  
Growth Curve Analysis ◽  
Clinical Assessments ◽  
Measuring Change ◽  
Quasi Experimental ◽  
Measure Change ◽  
Relationship Of ◽  
The Relationship ◽  
Methodological Difficulties

Although the goal of many clinical assessments and research studies is to measure how much people change between two occasions, the measurement of change is fraught with conceptual and methodological difficulties. One of the difficulties is that there are (at least) two different reasons to measure change: to determine if intervention had any effect, and to identify the correlates of change. These two goals work against each other, because the former requires there to be little difference in the amount of change among people in the same group, while the latter depends on inter-individual differences. The chapter also discusses various biases that exist when people are asked directly how much they think they have changed. This chapter addresses the issues of the relationship of change to the reliability of the scale, difficulties of measuring change in experimental and quasi-experimental studies, and new approaches to measuring change, such as growth curve analysis.

scholarly journals Contact-deformation mechanism of boundary friction

2020 ◽  
Vol 164 ◽  
pp. 14004
Author(s):  
Alexandr Dykha ◽  
Volodymyr Kukhar ◽  
Viktor Artiukh ◽  
Maxim Aleksandrovskiy
Keyword(s):  
Experimental Studies ◽  
Deformation Mechanisms ◽  
Internal Stresses ◽  
Stress And Strain ◽  
Relative Deformation ◽  
Contact Deformation ◽  
Surface Layers ◽  
Friction Units ◽  
Relationship Of ◽  
The Relationship

Research was conducted to determine the effect of lubricants on stress and strain in the contact of metal surfaces. Experiments were carried out on the introduction of a fixed and moving indenter in contact with a dry and lubricated surface.The steel spherical specimen was pressed into a lubricated and dry metal surface. The microstructures of the structure of the surface layer are studied under various conditions of deformation. The diagrams of the relative deformation of the surface layers are constructed. The mechanism of the formation and distribution of internal stresses for dry and greased contact is described. Experimental studies of the introduction of a moving steel indenter into a lubricated surface have been carried out. The relationship of the deformation mechanisms of lubricated surfaces with their wear resistance is determined. The results obtained are recommended for predicting the durability of lubricated friction units according to the criterion of contact strength.

scholarly journals Iron oxides and organic matter on soil phosphorus availability

2016 ◽  
Vol 40 (4) ◽  
pp. 369-379 ◽  
Author(s):  
Jessé Rodrigo Fink ◽  
Alberto Vasconcellos Inda ◽  
Tales Tiecher ◽  
Vidal Barrón
Keyword(s):  
Organic Matter ◽  
Iron Oxides ◽  
Soil Phosphorus ◽  
Phosphorus Availability ◽  
Phosphorus Sorption ◽  
Effective Strategies ◽  
Phosphorus Sorption Capacity ◽  
Soil Components ◽  
Relationship Of ◽  
The Relationship

ABSTRACT Continuous crop expansion has led to a growing demand for phosphate fertilizers. A sound knowledge of the dynamics of phosphorus, and its interaction with iron oxides and organic matter, can be useful to develop effective strategies for sustainable management, especially in a scenario of increasing shortage of mineral phosphate resources. In this paper, we review the relationship of phosphate to iron oxides and organic matter, and its effect on phosphorus availability. Crops typically obtain phosphate from weathered minerals and dissolved fertilizers. However, the amount of phosphorus present in the soil solution depends on the extent to which it is adsorbed or desorbed by iron oxides, which may be influenced by interactions with organic matter. Therefore, systems for fertilizer recomendation based on methodologies considering interactions between soil components such as oxides and organic matter, and the phosphorus sorption capacity resulting from such interactions (e.g. residual P analysis), may be more reliable to ensure efficient, rational use of phosphate.

THE INFLUENCE OF SOME PHYSICAL AND CHEMICAL PROPERTIES ON SOIL AGGREGATION AND RESPONSE TO VAMA

1966 ◽  
Vol 46 (2) ◽  
pp. 155-160 ◽  
Author(s):  
G. R. Saini ◽  
A. A. MacLean ◽  
J. J. Doyle
Keyword(s):  
Organic Matter ◽  
Soil Properties ◽  
Chemical Properties ◽  
Correlation Coefficients ◽  
Multiple Correlation Coefficient ◽  
Mean Weight Diameter ◽  
The Mean ◽  
Relationship Of ◽  
Physical And Chemical ◽  
The Relationship

The relationship of the mean weight diameter of water-stable aggregates to certain soil properties (clay, organic matter, free iron, free aluminum, and polysaccharide contents) and the relationship of the increase in aggregation caused by VAMA to the same properties of 24 New Brunswick soils were evaluated by correlation and regression analyses.Simple correlation coefficients relating aggregation to soil properties indicated that organic matter (r = 0.627), polysaccharides (r = 0.602), and aluminum (r = 0.679) were the most important factors. However, when the influence of each factor was separated by partial correlation, the coefficients were not significant. On the other hand, the combined effects of all factors as indicated by the multiple correlation coefficient (r = 0.743) was significant at the 1% level. The effect of the same soil properties on response to VAMA, as shown by increase in mean weight diameter, indicated that clay exerted the greatest influence. The relationship with other factors was nonsignificant.

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