The number and size of jet drops produced by air bubbles bursting on a fresh water surface

1994 ◽  
Vol 99 (C5) ◽  
pp. 10289 ◽  
Author(s):  
Donald E. Spiel
Keyword(s):  
Fresh Water ◽  
Water Surface ◽  
Air Bubbles

scholarly journals Eco Friendly Dye Extraction From Cyanophyta for Textiles

2021 ◽  
Vol 10 (4) ◽  
pp. 72-74
Author(s):  
E. Ramkumar ◽  
V.S. Bala Murali ◽  
T. Guna ◽  
S.M. Dharshan ◽  
S. Ajay Vishnu
Keyword(s):  
Fresh Water ◽  
Water Body ◽  
Water Surface ◽  
Water Bodies ◽  
Raw Material ◽  
The Sun ◽  
Major Threat ◽  
Dye Extraction ◽  
Dry Out ◽  
Sun Light

In countries like India there is always a scarcity for fresh water along with it polluting the available fresh water sources is a major threat. The major fresh water bodies are affected by eutrophication. It is the phenomenon in which algae forms a layer above the water surface and does not allow the sun light to enter into the water body. Due to this reason organisms which is present in the water body gets affected and the ecosystem gets damaged. The algae which are taken from the water bodies is dropped as waste in garbage or let to dry out on roads. “One man’s waste is other man’s treasure” so instead of wasting the collected algae, the algae can be used to prepare a dye which can be used to dye clothes for different uses. The collected algae are used as a raw material in an algal dying machine where the processes carried out are cleaning, drying the algae, grind it, boil them with water and other essentials, filter the residue and finally filtrate will be used to print on cloth.

New upgrades of Open-Loop Tracking Command (OLTC) tables of nadir altimeters in 2020 and benefits for inland waters users

2021 ◽  
Author(s):  
Simon Boitard ◽  
Sophie Le Gac ◽  
Denis Blumstein ◽  
Eric Munesa ◽  
François Boy ◽  
...  
Keyword(s):  
Fresh Water ◽  
Water Surface ◽  
Open Loop ◽  
Inland Waters ◽  
Signal Acquisition ◽  
Great Effort ◽  
Close Monitoring ◽  
Alos Palsar ◽  
Major Step ◽  
Tracking Mode

<p>Fresh water is an essential resource that requires a close monitoring and a constant preservation effort. The evolution of hydrological bodies water level constitutes a key indicator on the available quantity of fresh water in a given region. The limited extent of the in situ networks currently deployed has generated a growing interest in using space borne altimetry as a complementary data source to increase the coverage of emerged fresh water stocks and ensure a more global and continuous monitoring of their water surface height.</p><p>A great effort has been carried out over the past decade to improve altimeters’ capability to acquire quality measurements over inland waters. In particular, the Open-Loop Tracking Command (OLTC), which consists in calibrating the altimeter signal acquisition window with a prior information on the overflown hydrological surface height, represents a major evolution of the tracking function. This tracking mode’s efficiency is such that it is now stated as operational mode for current Sentinel-3 and Jason-3 missions as well as the recently launched Sentinel-6A mission. The improvements brought to onboard tables contents in 2017 (Jason-3), 2018 (Sentinel-3B) and 2019 (Sentinel-3A) enhanced and confirmed the OLTC performances.</p><p>In 2020, the onboard OLTC tables of the Jason-3, Sentinel-3A and Sentinel-3B missions have benefitted from further new major upgrades. The first version of the Sentinel-6A onboard OLTC tables holds the same content as Jason-3. The tracking command defined over Jason-3 and Sentinel-6A repeat cycle now accounts for more than 30,000 hydrological targets which represents five times more targets than in the previous version. For each Sentinel-3, the number of water body surface heights coded into the OLTC has been increased by a factor of 3 to 70,000. This further major step is made possible by the analysis and merging of the most recent digital elevation models (SRTM, MERIT and ALOS/PalSAR) and water bodies databases (HydroLakes, GRaND v1.3, SWBD, GSW). This methodology ensures coherency and consistent standards between all nadir altimetry missions and types of hydrological targets.</p><p>A detailed description of the 2020 upgrades will be given as well as measurements validation results obtained since their upload. An overview of the global validation of Sentinel-6A measurements over hydrological targets will also be presented.</p><p>These 2020 OLTC upgrades constitute a great asset for building a valuable and continuous record of the water surface height of worldwide lakes, rivers, reservoirs and wetlands. In addition, for a continuous improvement of the OLTC tracking mode, the users can check the content of the onboard OLTC tables over hydrological targets for both Sentinel-3 missions on the https://www.altimetry-hydro.eu/ web portal. When relevant, they can correct existing water surface heights or submit new targets.</p>

Dynamic mechanical measurements on fresh-water ice during freezing and thawing: preliminary results

2003 ◽  
Vol 81 (1-2) ◽  
pp. 469-477
Author(s):  
E R Fitzgerald
Keyword(s):  
Fresh Water ◽  
Tap Water ◽  
Air Bubbles ◽  
Freezing And Thawing ◽  
Sinusoidal Vibration ◽  
Water Ice ◽  
Air Bubble ◽  
Dynamic Mechanical ◽  
Complex Shear ◽  
Shear Compliance

An automated measurement system for elastic (J' ) and viscous (J'' ) components of complex shear compliance, J* = J' – iJ'', and the elastic (G' ) and viscous (G'' ) components of complex shear modulus, G* = G' + iG'' = 1/J*, has been used to obtain these material parameters for fresh-water ice during freezing and thawing. The system is reviewed briefly and yields mechanical loss tangents, J''/J' = G''/G', the shear-wave velocity and attenuation, in addition to shear compliance and modulus, at sinusoidal vibration frequencies from 2 to 10 000 Hz at temperatures between –25 and 150°C. Results reported here are chiefly at temperatures from 10 to –10°C. The required sample disk pairs, which are clamped to a central drive plate, are prepared outside the apparatus for solids and gels. Liquids of known volume are inserted between the drive plate and surrounding clamps at a separation distance, h, by a syringe to form sample disks of area, A = Volume / h. Measurements at 58 frequencies between 2 and 10 000 Hz require 3.5 min; several measurements at each temperature were made to test for equilibrium. Results for both tap and distilled water above freezing revealed high values of elastic (J' ) compliance that decreased sharply at 100 Hz and higher frequencies. Tap-water samples with 4 to 6% by volume air bubbles were less compliant ("stiffer") above freezing than samples with 0 to 1% by volume air, but when frozen, the samples with the smaller volume of air bubbles were less compliant, that is, had higher modulus values than the samples with high air-bubble volumes. Dynamic mechanical property changes in the transition from water to ice are compared to changes previously found during phase transitions in other materials. Further investigation on the effects of air-bubble volumes on dynamic mechanical properties of both water and ice is planned. PACS Nos.: 62.30+d, 62.40+i

scholarly journals III. The bionomics of certain air-breathing fishes of India, together with an account of the development of their air-breathing organs

1928 ◽  
Vol 216 (431-439) ◽  
pp. 183-219 ◽  
Keyword(s):  
Fresh Water ◽  
The Other ◽  
Fresh Water Fish ◽  
Air Bubbles ◽  
Air Breathing ◽  
Other Hand ◽  
Water Fish ◽  
Close Observation ◽  
To Come

It has long been known that certain species of fresh-water fish, inhabiting the rivers, lakes and ponds of India, are in the habit of leaving the water and making considerable excursions over the adjacent marshes and meadows, and some have been credited with the power of climbing trees. The older authors (Cuvier, Owen and Günther) explained the power which these fishes possessed of sustaining life outside the water by supposing that they carried with them, in reservoirs at the sides of the head, supplies of water by which the gills were kept moist. On the other hand, Taylor (1831) and specially Day (1808) and Hyrtl (1863) showed, as the result of close observation, that the reservoirs in question contained little or no water, and that the fish, when kept in tanks or globes, could be seen to come to the top at intervals and emit air-bubbles. It was, therefore, clear that the reservoirs in question contained not water but air, and that the fish must be regarded as true air-breathers. The fact that certain fish, such as Protopterus in Africa, Lepidosiren in S. America and Ceratodus in Australia, possess organs for breathing air as well as gills for respiring in water is well known; the structure and habits of these “double-breathers” (Dipnoi) form an integral part of the instruction given in every elementary course of Zoology. But the air-breathing organs of the Dipnoi are homologous with the lungs of the higher vertebrates, and the Dipnoi must be regarded as comparatively unchanged survivors from the time when the Devonian fish were making their first attempt to invade the land, at a period when no land-inhabiting air-breathing vertebrates existed.

Contact angle of air bubbles attached to an air-water surface in foam applications

Langmuir ◽  
1990 ◽  
Vol 6 (5) ◽  
pp. 995-1001 ◽  
Author(s):  
L. A. Lobo ◽  
A. Nikolov ◽  
A. Dimitrov ◽  
P. Kralchevski ◽  
D. T. Wasan
Keyword(s):  
Contact Angle ◽  
Water Surface ◽  
Air Bubbles

scholarly journals Temperature Gradient Daily Dynamics Area and Time Zoning for Local Analysis of Air-Water Interaction

2021 ◽  
Author(s):  
Christophil S. Medellu ◽  
Alfrits Komansilan
Keyword(s):  
Temperature Gradient ◽  
Fresh Water ◽  
Coastal Waters ◽  
Water Surface ◽  
Repeated Measurements ◽  
Local Analysis ◽  
Thermal Interaction ◽  
Water Interaction ◽  
Water Measurement

Abstract This article describes the results of the application of time zoning for air-water thermal interaction, and the temperature gradient daily dynamics area (TGDDA) parameters at six locations with different ecological conditions. The research locations consisted of two locations in lakes, two locations in coastal waters which were affected by fresh water and two locations in coastal waters which were not affected by fresh water. Measurement of air and water temperature was carried out in situ at several vertical positions with logarithmic distances to the water surface. The results of the analysis show that the analysis and modeling of the TGDDA parameters produce the time zoning of thermal interaction and TGDDA that vary between research locations. Repeated measurements on two consecutive days at the same location, resulted in almost the same TGDDA and time zoning duration of air-water thermal interaction. These results suggest that these parameters can be used to characterize air-water interactions. The results of this study serve as references to the chemical analysis of water and biota which is interactive or influenced by the dynamics of air-water thermal interactions.

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