The Relation of Phytoplankton Periodicity to the Nature of the Physico-Chemical Environment with Special Reference to Phosphorus. I. Morphometrical, Physical and Chemical Conditions

1957 ◽  
Vol 57 (2) ◽  
pp. 300 ◽  
Author(s):  
Allan Tucker
Keyword(s):  
Special Reference ◽  
Chemical Environment ◽  
Physico Chemical ◽  
Chemical Conditions ◽  
Physical And Chemical

scholarly journals Some aspects of the ecology of freshwater algae in the Densu River and two tributaries in Southern Ghana

2014 ◽  
Vol 3 (2) ◽  
pp. 246-257 ◽  
Author(s):  
Ted Y Annang ◽  
RD Yirenya-Tawiah ◽  
GC Clerk ◽  
Thomas Smith
Keyword(s):  
River Water ◽  
Sampling Site ◽  
Freshwater Algae ◽  
Sample Collection ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Physical And Chemical Parameters ◽  
Chemical Conditions ◽  
Physical And Chemical ◽  
Southern Ghana

Studies on the composition and abundance of the phytoplankton in River Densu and two of its tributaries, Rivers Adeiso and Nsakir were carried out at ten sampling sites, including seven from different regions of the river basin namely Afuaman, Akwadum, Densuso, Manhean, Machigeni, Nsawam and Weija, as well as Adeisoand Pokuase. Sampling was done monthly at each sampling site from January to December, 2006. Physical and chemical parameters of river water were studied. The parameters of the river water varied with the sampling sites and the time of the year. Water samples for phytoplankton identification and enumeration were collected at each sampling site. Physico-chemical conditions of the river were assessed during sample collection or in the laboratory. Correlation analysis showed that there was a positive correlation between algal genera and the measured physical and chemical parameters of the river water. DOI: http://dx.doi.org/10.3126/ije.v3i2.10637 International Journal of the Environment Vol.3(2) 2014: 246-257

scholarly journals Periphyton Response Analysis to the Pollution in Seagrass Ecosystem Panjang Island, Banten

2018 ◽  
Vol 23 (3) ◽  
pp. 113
Author(s):  
Yayuk Sugianti ◽  
Barti Setiani Muntalif ◽  
Priana Sudjono
Keyword(s):  
Water Quality Assessment ◽  
Organic Pollution ◽  
Inorganic Materials ◽  
Response Analysis ◽  
Physico Chemical ◽  
The Status ◽  
Standard Quality ◽  
Seagrass Ecosystems ◽  
Chemical Conditions ◽  
Physical And Chemical

Increases in coastal pollutants, largely due to human activity on land, have an impact on seagrass ecosystems. The high sedimentation in the waters causes an increase in the concentration of sludge, organic matter, nutrients, and turbidity which reduce the depth that can be reached by sunlight. The condition affects seagrass ecosystems adversely. Changes in water condition can be illustrated by the presence of water organisms. One dominant organism in seagrass ecosystems is periphyton. The existence of periphyton in the waters is determined by physical and chemical conditions of the waters because it has specific limit of tolerance, which causes different community structure. To analyze periphyton response to the changes of environmental quality in seagrass ecosystems, Shannon Winner diversity and Saprobic Indices were measured at Panjang Island, Banten. The results of water quality assessment indicates the status of aquatic seagrass of the island considered as polluted to heavy polluted. It is observed from some physico-chemical parameters that exceeded the standard quality for the life of seagrass ecosystems and marine life. Based on the classification and saprobic coefficient using periphyton biological parameters, the condition of seagrass land ecosystem in the island is classified into β Mesosaprobic to β/α Mesosaprobic phase, which indicates light to medium pollution with pollutants including organic and inorganic materials. Several types of dominant periphyton were discovered during the observations, including Meridion sp, Navicula sp, Nitzschia sp and Synedra sp. This periphyton species belong to Bacillariophyceae class (Family Chrysophyta) that is commonly used to assess the condition of eutrophication and organic pollution on waters.

scholarly journals Physico-chemical conditions of existence of early Cambrian chemotrophic microbiota in zone of influence of ore-forming hydrothermal solutions

2019 ◽  
Vol 486 (3) ◽  
pp. 331-335
Author(s):  
V. A. Simonov ◽  
A. A. Terleev ◽  
A. V. Kotlyarov ◽  
D. A. Tokarev ◽  
A. V. Kanygin
Keyword(s):  
Low Temperature ◽  
Hydrothermal Systems ◽  
Early Cambrian ◽  
Hydrothermal Solutions ◽  
Ore Body ◽  
Physico Chemical ◽  
Zone Of Influence ◽  
Chemical Conditions ◽  
Physical And Chemical ◽  
Operating Zone

Complex researches of the pyrite Early Cambrian Kyzyl-Tashtyg deposit (East Tuva) have allowed to reconstruct paleohydrothermal systems, to find out physical and chemical conditions of hydrothermal processes, and also to establish features of existence of ancient hydrothermal biota in the operating zone of the solutions, participating at all stages of formation of ore-bearing structures, since influence of postmagmatic fluids and finishing low temperature hydrotherms. The representative data on biota has been received at studying of the objects, which were in a zone of influence of rather low temperature hydrothermal systems. In one cases findings of microorganisms are dated for basalt complexes, containing ore body, and in other cases the found fauna is connected with ferruginous-siliceous sediments. It has been found out that microorganisms in the tonsil cavities of basalts evolved at the temperatures nearby 110-140°С under the influence of hydrothermal solutions. Much lower temperatures (to 100 °С) existed at development of micro-fossils in the quartz-hematite hydrothermal constructions of Kyzyl-Tashtyg deposit.

scholarly journals Biodiversity and seasonal distribution of benthic diatom assemblages as an indicator of water quality of small karstic river in Bosnia and Herzegovina

2021 ◽  
Vol 80 (2) ◽  
Author(s):  
Anita Dedić ◽  
Dubravka Hafner ◽  
Ana Antunović ◽  
Jasmina Kamberović ◽  
Svjetlana Stanić-Koštroman ◽  
...  
Keyword(s):  
Bosnia And Herzegovina ◽  
Ecological Status ◽  
Quantitative Composition ◽  
Diatom Indices ◽  
Low Concentrations ◽  
Physico Chemical ◽  
Status Assessment ◽  
Chemical Conditions ◽  
Physical And Chemical

The aims of this paper were to describe seasonal changes in the qualitative and quantitative composition of diatom taxa and the potential application of benthic diatoms for ecological status evaluation. Diatom indices (IPS and TI) were calculated from data from three different locations along a longitudinal profile of the Bunica, a small karstic river in Bosnia and Herzegovina. A total of 147 taxa were recorded in 12 samples. The most common taxa were Meridion circulare (Greville) C.Agardh and Ulnaria ulna (Nitzsch) Compère. Physical and chemical analyses showed low concentrations of nutrients, good oxygenation, typical pH for carbonate bed/origin and generally oligotrophic conditions and high ecological status. All sites had similar physico-chemical conditions and there were only few seasonal differences. Ordination of the diatom data showed that samples showed neither longitudinal nor seasonal patterns. Median value for IPS (16.8) and for TI (7.3) can be possible ‘‘expected’’ values for ecological status assessment for small karstic rivers in the Mediterranean region. We propose the use of the phytobenthos Intercalibration Common Metric (pICM - an index that combines the IPS and TI) as a national metric for countries developing WFD diatom methods at a late stage. One situation is described, and a solution, which is potentially transferable to other locations in Bosnia and Herzegovina and also to other countries facing similar challenges.

Physical and chemical conditions for longterm functioning of restorations with zirconium-based framework: literature review

2019 ◽  
Vol 1 (5) ◽  
pp. 48-51
Author(s):  
Z. S. Khabadze ◽  
G. K. Davreshyan ◽  
M. S. Terekhov ◽  
Yu. A. Bakaev ◽  
S. M. Abdulkerimova ◽  
...  
Keyword(s):  
Literature Review ◽  
Zirconium Dioxide ◽  
Heating And Cooling ◽  
Physico Chemical ◽  
Oral Environment ◽  
Chemical Conditions ◽  
Physical And Chemical ◽  
Google Search ◽  
Selection Of

The aim of the study is to determine the optimal physico-chemical conditions and factors for the long-term perspective of zirconia-based restorations. Materials and methods Information was searched in English without time limits in the PubMed electronic database, a Google search and literature lists of relevant studies and reviews. Full-text articles from 2003 to 2018 were selected, in which studies of frameworks made of zirconium dioxide, a protocol for changing firing temperatures, and a description of the structure are described. Results. Totally 79 articles were identified. After the selection of articles on the inclusion criteria and removal of duplicate articles, the total number was 5. The review of the literature included studies of 3 types of zirconium: 3Y-TZP, ATZ, 12Ce-TZP. In a number of studies, the authors studied experimentally the influence of the oral environment on the long-term functioning of zirconium, and a number of authors conducted a study on the effect of heating and cooling gradients, as well as mechanical processing of zirconium frameworks. Conclusion. This literature review has shown the optimal physicochemical conditions and factors for the long-term prospects for restorations with a zirconia-based framework, starting from its composition, technical and laboratory stages, and pumping over the oral cavity factors. The combination of these factors can reduce the effect of the transition of zirconium dioxide from the tetragonal to the monoclinic phase, as well as reduce the stress outcomes resulting from the processing of zirconia frameworks and their facing layer.

Authenticity Identification of Carbonated Alcochol-Free Beverages

Food Industry ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 16-22
Author(s):  
Irina Reznichenko ◽  
Maria Kondratieva
Keyword(s):  
Mass Fraction ◽  
Soft Drinks ◽  
Alcoholic Beverages ◽  
Consumer Market ◽  
Score System ◽  
Regulatory Documents ◽  
Chemical Indicators ◽  
Physico Chemical ◽  
Alcoholic Drinks ◽  
Physical And Chemical

The article concerns the counterfeiting problem of non-alcoholic drinks sold on the consumer market of the Russian Federation; provides data on drinks fraud methods (assortment, qualitative, quantitative and informational types). Strengthening quality control of soft drinks is one of the main directions of providing consumers with qualitative products. The authors presented authenticity identification results of carbonated soft drinks sold on the Kemerovo consumer market for compliance with the current regulatory documents requirements; run the consumer criteria analysis for the drinks identification of various brands. They obtained data on the labeling and packaging identification of selected non-alcoholic carbonated drinks samples for the compliance with current regulatory documents. A man recorded the compliance. There was an absence of the quantitative counterfeiting identification. The study described results of the organoleptic and physico-chemical quality indicators research. According to the GOST 28188-2014 “Non-Alcoholic Beverages. General Technical Conditions” the authors evaluated beverages quality by such physical and chemical indicators as the mass fraction of dry substances, acidity, and the mass fraction of carbon dioxide. The researchers run the organoleptic indicators analysis according to a score system. Authenticity identification of the selected drinks samples showed that there are no signs of counterfeiting and the products are of high quality.

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.

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