scholarly journals The results of studies on the extension of methodological capabilities of determining physico-chemical conditions of lead-based liquid-metal coolants

2020 ◽  
Vol 6 (2) ◽  
pp. 71-75
Author(s):  
Sergey V. Salaev ◽  
Radomir Sh. Askhadullin ◽  
Konstantin D. Ivanov ◽  
Alexandr Yu. Legkikh ◽  
Said-Ali S. Niyazov
Keyword(s):  
Thermal Cycling ◽  
Quantitative Data ◽  
Thermodynamic Activity ◽  
Structural Steels ◽  
Martensitic Steels ◽  
Saturation Concentration ◽  
Physico Chemical ◽  
External Conditions ◽  
Chemical Conditions ◽  
Oxygen Impurities

The authors consider examples of using the thermal cycling method for heavy lead- and lead-bismuth-based coolants with simultaneous measurement of the thermodynamic activity (TDA) parameter of oxygen impurities. In these experiments, structural EI852 and EP823 ferritic-martensitic steels as well as EP302 austenitic steel were used as sources of iron impurities. As a result of the experiments, it was found that iron oxides previously formed in the coolant, as such or in the form of an oxide film on the structural steels, are not inert phases in heavy coolants, but can exchange iron and oxygen with the melt. The nature of this exchange depends both on the actual coolant impurity state and on external conditions, including, first of all, temperature. The experimental data obtained by thermal cycling of lead- and lead-bismuth coolants were analyzed both in the region of relatively high oxygen TDA values close to the oxygen saturation concentration and in the region of sufficiently low values of this parameter close to the saturation concentration of iron impurities. It is concluded that the proposed coolant thermal cycling method is informationally significant and can be recommended for further use, for example, to obtain quantitative data on the content of iron impurities in the coolant.

Viability of nematode eggs in high rate algal ponds: the effect of physico-chemical conditions

2000 ◽  
Vol 42 (10-11) ◽  
pp. 371-374 ◽  
Author(s):  
S. Araki ◽  
J. M. González ◽  
E. de Luis ◽  
E. Bécares
Keyword(s):  
Hydraulic Retention Time ◽  
Pilot Scale ◽  
High Rate ◽  
Sterile Water ◽  
Egg Viability ◽  
High Rate Algal Ponds ◽  
Helminth Eggs ◽  
Physico Chemical ◽  
Nematode Eggs ◽  
Chemical Conditions

The viability of Parascaris equorum eggs was studied in two experimental pilot-scale high-rate algal ponds (HRAPs) working in parallel with 4 and 10 days hydraulic retention time respectively. Semi-permeable bags of cellulose (15000 daltons pore size) were used to study the effect of physico-chemical conditions on the survival of these helminth eggs. Three thousand eggs were used in each bag. Replicates of these bags were submerged for 4 and 10 days in the HRAPs and egg viability was compared with that in control bags submerged in sterile water. After 4 days exposure, 60% reduction in viability was achieved, reaching 90% after 10 days, much higher than the 16% and 25% found in the control bags for 4 and 10 days respectively. Ionic conditions of the HRAP may have been responsible for up to 50–60% of the egg mortality, suggesting that mortality due to the ionic environment could be more important than physical retention and other potential removal factors.

scholarly journals Compartmentalization of bacterial and fungal microbiomes in the gut of adult honeybees

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Matteo Callegari ◽  
Elena Crotti ◽  
Marco Fusi ◽  
Ramona Marasco ◽  
Elena Gonella ◽  
...  
Keyword(s):  
Gut Microbiome ◽  
Bacterial Phylotypes ◽  
Specific Variable ◽  
The Core ◽  
Physico Chemical ◽  
Metabolic Conditions ◽  
Chemical Conditions ◽  
And Behavior

AbstractThe core gut microbiome of adult honeybee comprises a set of recurring bacterial phylotypes, accompanied by lineage-specific, variable, and less abundant environmental bacterial phylotypes. Several mutual interactions and functional services to the host, including the support provided for growth, hormonal signaling, and behavior, are attributed to the core and lineage-specific taxa. By contrast, the diversity and distribution of the minor environmental phylotypes and fungal members in the gut remain overlooked. In the present study, we hypothesized that the microbial components of forager honeybees (i.e., core bacteria, minor environmental phylotypes, and fungal members) are compartmentalized along the gut portions. The diversity and distribution of such three microbial components were investigated in the context of the physico-chemical conditions of different gut compartments. We observed that changes in the distribution and abundance of microbial components in the gut are consistently compartment-specific for all the three microbial components, indicating that the ecological and physiological interactions among the host and microbiome vary with changing physico-chemical and metabolic conditions of the gut.

scholarly journals Dissolved organic nutrients at the interface of fresh and marine waters: flow regime changes, biogeochemical cascades and picocyanobacterial blooms—the example of Florida Bay, USA

2021 ◽  
Author(s):  
Patricia M. Glibert ◽  
Cynthia A. Heil ◽  
Christopher J. Madden ◽  
Stephen P. Kelly
Keyword(s):  
Water Quality ◽  
Anthropogenic Activities ◽  
Florida Bay ◽  
Climate Conditions ◽  
Regime Changes ◽  
Physico Chemical ◽  
Organic Nutrients ◽  
High Concentrations ◽  
Chemical Conditions ◽  
Favorable Conditions

AbstractThe availability of dissolved inorganic and organic nutrients and their transformations along the fresh to marine continuum are being modified by various natural and anthropogenic activities and climate-related changes. Subtropical central and eastern Florida Bay, located at the southern end of the Florida peninsula, is classically considered to have inorganic nutrient conditions that are in higher-than-Redfield ratio proportions, and high levels of organic and chemically-reduced forms of nitrogen. However, salinity, pH and nutrients, both organic and inorganic, change with changes in freshwater flows to the bay. Here, using a time series of water quality and physico-chemical conditions from 2009 to 2019, the impacts of distinct changes in managed flow, drought, El Niño-related increases in precipitation, and intensive storms and hurricanes are explored with respect to changes in water quality and resulting ecosystem effects, with a focus on understanding why picocyanobacterial blooms formed when they did. Drought produced hyper-salinity conditions that were associated with a seagrass die-off. Years later, increases in precipitation resulting from intensive storms and a hurricane were associated with high loads of organic nutrients, and declines in pH, likely due to high organic acid input and decaying organic matter, collectively leading to physiologically favorable conditions for growth of the picocyanobacterium, Synechococcus spp. These conditions, including very high concentrations of NH4+, were likely inhibiting for seagrass recovery and for growth of competing phytoplankton or their grazers. Given projected future climate conditions, and anticipated cycles of drought and intensive storms, the likelihood of future seagrass die-offs and picocyanobacterial blooms is high.

scholarly journals Croonian lecture.—Observations on isolated nerve. Electrical changes a measure of physico-chemical change

1896 ◽  
Vol 59 (353-358) ◽  
pp. 308-312
Keyword(s):  
Chemical Change ◽  
Physico Chemical ◽  
Chemical Conditions

The present investigation arises from experiments undertaken to determine autographically the varying relations between the magnitude of electrical change and the magnitude of stimulation in nerve under various chemical conditions.

SECONDARY CHANGES IN CARBONATE ROCKS OF OIL AND GAS COMPLEXES

2020 ◽  
pp. 18-23
Author(s):  
M.A. Tugarova
Keyword(s):  
Carbonate Rocks ◽  
Oil And Gas ◽  
Carbonate Reservoirs ◽  
Fundamental Importance ◽  
Schematic Diagram ◽  
Reservoir Properties ◽  
Physico Chemical ◽  
Chemical Conditions ◽  
First Time

The article considers the secondary transformations of carbonate rocks of oil and gas complexes, which are of fundamental importance in the formation of reservoir properties. For the first time, a schematic diagram, illustrating the regularities of secondary processes in carbonate reservoirs and their relationship with the physico-chemical conditions of the stratosphere is proposed.

scholarly journals Interstellar and interplanetary solids in the laboratory

2015 ◽  
Vol 11 (A29B) ◽  
pp. 416-419 ◽  
Author(s):  
Emmanuel Dartois ◽  
Ivan Alata ◽  
Cécile Engrand ◽  
Rosario Brunetto ◽  
Jean Duprat ◽  
...  
Keyword(s):  
Interstellar Medium ◽  
Environmental Parameters ◽  
Interstellar Matter ◽  
Additional Information ◽  
Set Constraints ◽  
Physico Chemical ◽  
Space Environments ◽  
Chemical Conditions ◽  
Extraterrestrial Material ◽  
Shed Light

AbstractThe composition of interstellar matter is driven by environmental parameters and results from extreme interstellar medium physico-chemical conditions. Astrochemists must rely on remote observations to monitor and analyze the interstellar solids composition. They bring additional information from the study of analogues produced in the laboratory, placed in simulated space environments. Planetologists and cosmochemists access and spectroscopically examine collected extraterrestrial material in the laboratory. Diffuse interstellar medium and molecular clouds observations set constraints on the composition of organic solids that can then be compared with collected extraterrestrial materials analyses, to shed light on their possible links.

scholarly journals Study Of Impacts Of Oil Spill On The Sundarbans Mangrove Forest Of Bangladesh

2015 ◽  
Vol 41 (1) ◽  
pp. 75-94 ◽  
Author(s):  
Abdullah Harun Chowdhury ◽  
Md Ali Akber
Keyword(s):  
Oil Spill ◽  
Oil Content ◽  
World Heritage Site ◽  
Heritage Site ◽  
Physico Chemical ◽  
Common Birds ◽  
Chemical Conditions ◽  
Monitor Lizards ◽  
Total Study Area ◽  
The Sundarbans

Studies were carried out on the recent oil spill in the Sundarbans of Bangladesh to findout the immediate impacts on the ecosystem of the Sundarbans after oil spilling. Morethan 500 km2 areas out of the total study area have been affected seriously by the oil spillcontamination on 9 December 2014. Recorded data of the physico-chemical conditions,oil content, productivity, diversity and abundance of phyto-zooplankton and benthos ofwater, and oil content in soil indicate that the water and soil of the Eastern part of theSundarbans were polluted by the oil contamination. Results also indicate that seedlings,mangrove algae, eggs and hatchlings of commercially valuable fishes, mudskippers, mudcrabs, snails, monitor lizards were affected due to oil spill. Regeneration of the Sundritrees; intertidal zone bird - ‘Masked finfoot’, common birds, fishing cat, otter, dolphins,crocodile would be affected due to the oil spill. Long term monitoring, in depth researchand proper implementation of all rules and regulations are necessary to save the fragileecosystem of the Sundarbans-the UNESCO declared world heritage site. Asiat. Soc. Bangladesh, Sci. 41(1): 75-94, June 2015

scholarly journals SOIL DEVELOPMENT AND PROPERTIES OF MICROBIAL BIOMASS SUCCESSION IN RECLAIMED SITES IN BULGARIA

2019 ◽  
Vol 7 ◽  
pp. 1008-1014
Author(s):  
Veneta V. Stefanova ◽  
Petar G. Petrov
Keyword(s):  
Heavy Metals ◽  
Microbial Activity ◽  
Vegetation Type ◽  
Soil Microbial Activity ◽  
Soil Development ◽  
Substrate Quality ◽  
Mining Sites ◽  
Soil Microbial ◽  
Physico Chemical ◽  
Chemical Conditions

One of the most important preconditions of ecosystem rehabilitation in post mining landscapes is the process of soil development. In this context, the microbial activity in soil plays an important role. Microbial activity was studied in several reclaimed post mining sites resulted from the mining activity in Bulgaria. The studied soils are characterized by different biogenicity. The development of the total microflora in soils is higher in the surface layers but in depth, their number decreases due to the inhibiting effect of pollutants (heavy metals) and a change in the physico-chemical conditions. The dominant microorganisms are non-spore bacteria and all studied soils showed the development of pigment types of bacteria resulting from the high content of heavy metals. The composition of the microorganisms is poor, which can be taken as an indicator that the microbicenosis is still in the process of formation. In depth, their number is reduced by applying the effect of contamination. The mineralization coefficient values are the highest in the field with the greatest age of re-cultivation, where humidification is the most advanced. The study shows that vegetation type and litter quality seem to be more important for soil microbial activity than the substrate quality on the reclaimed sites.

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