scholarly journals Sedimentation rate and physical properties of bottom sediments in the Angara reservoirs under the cyclical conditions of the level regime

LITOSFERA ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 271-279
Author(s):  
G. A. Karnaukhova
Keyword(s):  
Organic Matter ◽  
Physical Properties ◽  
Bottom Sediments ◽  
Sedimentation Rate ◽  
Engineering Geology ◽  
Absorption Capacity ◽  
High Porosity ◽  
Research Subject ◽  
Standard Methods ◽  
Level Regime

Research subject. The article presents the results of a study of sedimentation rate and physical properties of bottom sediments in the Angara reservoirs under controlled level regimes. Materials and methods. The work was based on the materials of fieldwork carried out by the author on the Angara reservoirs in 1972–2017 and open-access literature sources. The physical properties and particle size distribution of bottom sediments were determined by the standard methods of engineering geology. Results. It was found that the controlled level regime determines the time cycles of sedimentation in reservoirs, sources of sediment-forming material, sedimentation rate and ambiguity of the physical properties of bottom sediments. Conclusions. During transgressions, sands, coarse aleurites and fine-aleurite silts accumulate in reservoirs most intensively; however, during regressions, coarse aleurites and aleurite-clayey silts are accumulated. During transgressions, all types of sediments are characterised by the highest sediment density, sediment skeleton density and absorption capacity, while coarse aleurites and fine-aleurite silts exhibit high natural humidity levels. In addition, coarse aleurites are characterised by a high porosity, while fine-aleurite and aleurite-clayey silts are characterised by a high content of organic matter. During regressions, the porosity of sands, fine-aleurite and aleurite-clayey silts increases, the content of organic matter in sands and coarse aleurites increases, and all types of sediments become more saturated with carbonates.

HEAVY METAL SPECIATION IN BOTTOM SEDIMENTS OF THE VYSHNEVOLOTSKY RESERVOIR

2018 ◽  
pp. 46-54
Author(s):  
O. A. Lipatnikova
Keyword(s):  
Heavy Metal ◽  
Organic Matter ◽  
Bottom Sediments ◽  
Metal Speciation ◽  
Organic Matter Content ◽  
Water Reservoir ◽  
Matter Content ◽  
Heavy Metal Speciation ◽  
Mobile Forms ◽  
Manganese Hydroxides

The study of heavy metal speciation in bottom sediments of the Vyshnevolotsky water reservoir is presented in this paper. Sequential selective procedure was used to determine the heavy metal speciation in bottom sediments and thermodynamic calculation — to determine ones in interstitial water. It has been shown that Mn are mainly presented in exchangeable and carbonate forms; for Fe, Zn, Pb и Co the forms are related to iron and manganese hydroxides is played an important role; and Cu and Ni are mainly associated with organic matter. In interstitial waters the main forms of heavy metal speciation are free ions for Zn, Ni, Co and Cd, carbonate complexes for Pb, fulvate complexes for Cu. Effects of particle size and organic matter content in sediments on distribution of mobile and potentially mobile forms of toxic elements have been revealed.

ALUMINUM ALLOY 201.0

Alloy Digest ◽  
1995 ◽  
Vol 44 (7) ◽  
Keyword(s):  
Aluminum Alloy ◽  
High Temperature ◽  
Physical Properties ◽  
High Strength ◽  
Heat Treating ◽  
Absorption Capacity ◽  
Casting Alloy ◽  
Permanent Mold ◽  
Energy Absorption Capacity ◽  
Temperature Performance

Abstract ALUMINUM ALLOY 201.0 is a structural casting alloy available as sand, permanent mold and investment castings. It is used in structural casting members, applications requiring high tensile and yield strengths with moderate elongation, and where high strength and energy-absorption capacity are needed. This datasheet provides information on composition, physical properties, and elasticity as well as creep and fatigue. It also includes information on high temperature performance as well as casting, heat treating, machining, joining, and surface treatment. Filing Code: AL-336. Producer or source: Various aluminum companies.

Paleohydrological processes in Siling-CO (lake) in the Qing-Zang (Tibetan) Plateau based on the physical properties of its bottom sediments

1991 ◽  
Vol 18 (9) ◽  
pp. 1779-1781 ◽  
Author(s):  
Kenji Kashiwaya ◽  
Katsumi Yaskawa ◽  
Baoin Yuan ◽  
Jiaqi Liu ◽  
Zhaoyan Gu ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Physical Properties ◽  
Bottom Sediments

PERSISTENCE OF CHANGES IN SELECTED SOIL CHEMICAL AND PHYSICAL PROPERTIES AFTER PIPELINE INSTALLATION IN SOLONETZIC NATIVE RANGELAND

1987 ◽  
Vol 67 (4) ◽  
pp. 747-763 ◽  
Author(s):  
M. A. NAETH ◽  
A. W. BAILEY ◽  
W. B. McGILL
Keyword(s):  
Organic Matter ◽  
Physical Properties ◽  
Bulk Density ◽  
Organic Matter Content ◽  
Matter Content ◽  
Chemical Changes ◽  
Ecosystem Responses ◽  
Native Prairie ◽  
Natural Gas Pipelines ◽  
Mixed Prairie

A study was conducted in Solonetzic mixed prairie of southern Alberta to evaluate and determine the longevity of selected ecosystem responses to pipeline installation. Five adjacent natural gas pipelines on a series of rights-of-way (ROW) were studied at three sites. The lines, which were installed in 1957, 1963, 1968, 1972 and 1981, had diameters of 86, 86, 91, 107 and 107 cm, respectively. Soils were analyzed for particle size distribution, bulk density, pH, electrical conductivity, ion composition, and organic matter content. It was concluded that pipeline construction in Solonetzic mixed prairie range-land initially tended to improve surface soil chemical and physical properties compared to blowouts, but reduced soil quality in vegetated native prairie. Surface bulk density increased to 1.3–1.6 Mg m−3 from an undisturbed density of 0.9–1.0 Mg m−3. Increased densities were evident to 55 cm in all 1981 transects except the trench where subsurface densities were reduced. Chemical changes were associated with reduced organic matter and increased salts at the surface. On the basis of differences between the various ages of pipelines (1981, youngest; 1957, oldest) there was evidence for greater amelioration of chemical changes than of physical disturbances over time. The time needed to restore half the lost organic matter was estimated to be approximately 50 y. Key words: Pipeline, Solonetzic soil, rangeland (native), soil chemistry, bulk density, reclamation

Advances in understanding the transformation of engineered nanoparticles in the environment

2014 ◽  
Vol 86 (7) ◽  
pp. 1129-1140 ◽  
Author(s):  
Setare Tahmasebi Nick ◽  
Ali Bolandi ◽  
Tova A. Samuels ◽  
Sherine O. Obare
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Physical Properties ◽  
Recent Work ◽  
Environmental Remediation ◽  
Health And Safety ◽  
Green Manufacturing ◽  
Consumer Products ◽  
Engineered Nanoparticles ◽  
Proactive Study

AbstractEngineered nanoparticles (ENPs) are known to possess unique size and shape dependent chemical and physical properties. As a result of their properties, ENPs have been effective in several important applications including catalysis, sensor design, photonics, electronics, medicine, and the environmental remediation of toxic pollutants. Such properties and applications have led to an increase in the manufacture of ENPs and a rise in their presence in consumer products. The increase of ENPs in consumer products presents several opportunities and challenges, and necessitates a proactive study of their health and safety. This article highlights some recent work in which we have studied the effect of exposure of well-defined ENPs to pesticides and the effect of pH and dissolved organic matter. We also summarize our work and that of others who have studied the toxicity of ENPs with microorganisms. The results provide insights on the need for green manufacturing strategies of ENPs, their use and safe disposal practices.

scholarly journals Functional and pasting characteristics of pupuru and pupuru analogues from cassava (Manihot esculenta) and breadfruit (Artocarpus altilis) blends

2020 ◽  
Vol 13 (1) ◽  
pp. 51-68
Author(s):  
O. F. Akinyele ◽  
A. V. Ikujenlola ◽  
T. O. Omobuwajo
Keyword(s):  
Water Absorption ◽  
Manihot Esculenta ◽  
Pasting Properties ◽  
Absorption Capacity ◽  
Peak Time ◽  
Standard Methods ◽  
Artocarpus Altilis ◽  
Swelling Power ◽  
Pasting Characteristics ◽  
Pasting Temperature

Abstract Pupuru and pupuru analogues are fermented, smoked food products usually produced from cassava or cassava substituted with a varying ratio of breadfruit. This study aims at determining and comparing the functional and pasting characteristics of pupuru and pupuru analogues with a view to expanding the utilization of breadfruit as pupuru analogue. The functional properties (water absorption capacity (%), swelling power (g/g), solubility (%)) and pasting characteristics were determined using standard methods. The results showed that the yield of the products ranged between 24.66 and 29.65%, and it was not affected by the amount of breadfruit substituted. The water absorption capacities of the pupuru and pupuru analogues ranged between 216.0 and 449.0%; this parameter increased with temperature increase. Both swelling power and solubility had a rapid increase from 80 °C to 90 °C. Pasting temperature ranged between 73.15 and 83.66 °C, with peak time between 4.58 and 5.33 min. The final viscosity ranged between 94.08 and 391.83 RVU, and it decreased with increase in breadfruit substitution. The study concluded that adding breadfruit to cassava in pupuru analogue production improved some of the functional and pasting properties of the product.

scholarly journals Development of nanostructured bioplastic material for wound healing

2021 ◽  
Author(s):  
Ilmira R. Gilmutdinova ◽  
Elena Kostromina ◽  
Regina D. Yakupova ◽  
Petr S. Eremin
Keyword(s):  
Hyaluronic Acid ◽  
Clinical Practice ◽  
Physical Properties ◽  
Human Fibroblasts ◽  
Fibroblast Cell ◽  
Human Skin Fibroblast ◽  
High Porosity ◽  
The Matrix ◽  
Photochemical Crosslinking ◽  
Fibroblast Cell Culture

The development of new biomaterials whose characteristics are as close as possible to the properties of living human tissues is one of the most promising areas of regenerative medicine. This work aimed at creating a bioplastic material based on collagen, elastin and hyaluronic acid and studying its structure and properties to assess the prospects for further use in clinical practice. Bioplastic material was obtained by mixing collagen, hyaluronic acid and elastin in predetermined proportions with distilled water. We treated the material with photochemical crosslinking to stabilize biofilm in a liquid medium and form a nanostructured scaffold. A commercial human skin fibroblast cell culture was used to assess the biomaterial cytotoxicity and biocompatibility. The visualization and studies of the biomaterial structure were performed using light and scanning electron microscopy. It has been shown that the obtained biomaterial is characterized by high resilience; it has also a high porosity. The co-culturing of the bioplastic material and human fibroblasts did not reveal any of its cytotoxic effects on cells in culture. It was shown that the biomaterial samples could maintain physical properties in the culture medium for more than 10 days, while the destruction of the matrix was observed 3–4 weeks after the beginning of incubation. Thus, the created biomaterial can be used on damaged skin areas due to its physical properties and structure. The use of the developed biomaterial provides effective conditions for good cell proliferation, which allows us to consider it as a promising wound cover for use in clinical practice.

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