the acute toxicity of salts of alkali and alkaline earth metals, such as sodium (na), potassium (k), calcium (ca) and magnesium (mg) were studied on the egg and larval stages of indian major carp labeo rohita (hamilton). the acute toxicity experiments were conducted followed by the range finding bioassay tests. the experiments were conducted in triplicates. the cumulative percentage of dead or ...

[1] The net influx of water into the deep mantle by plate tectonics has been poorly constrained because it is difficult to quantify how efficiently subducting slabs are devolatilized on a global scale. The significance of deep water cycle in the Earth history is similarly ambiguous because it depends critically on when plate tectonics started and how it evolved through time. Here I show that, u...

We report spectroscopic observations (400−800 nm, R ≈ 100) of Earthshine in June, July and October 2001 from which normalised Earth albedo spectra have been derived. The resulting spectra clearly show the blue colour of the Earth due to Rayleigh diffusion in its atmosphere. They also show the signatures of oxygen, ozone and water vapour. We tried to extract from these spectra the signature of E...

assess the ecological effects of economic activity on the water, earth and man in the iranian economy approach using input - output tablewater is a vital resource for each biological and economic phenomenon. water is considered as a production input. production is not possible without water in all economic sectors. also, the environment including air, soil, fauna and plants utilize water in the...

The reason why the water in wells becomes colder in summer is that the earth is then rarefied by the heat, and releases into the air all the heat-particles it happens to have. So, the more the earth is drained of heat, the colder becomes the moisture that is concealed in the ground. On the other hand, when all the earth condenses and contracts and congeals with the cold, then, of course, as it ...

Compared to Earth’s atmosphere, Mars has a thin CO2-rich atmosphere with a surface pressure of about 700 Pa. When normalized to planetary mass (mass of Mars is 10.7% of that of Earth), the abundance of volatiles on Mars is about 0.07% to 6% of that on Earth (when CO2 in terrestrial carbonates is included). Is the depletion of volatiles on Mars a primary feature (because less volatiles accreted ...

Close-in giant planets (e.g., "hot Jupiters") are thought to form far from their host stars and migrate inward, through the terrestrial planet zone, via torques with a massive gaseous disk. Here we simulate terrestrial planet growth during and after giant planet migration. Several-Earth-mass planets also form interior to the migrating jovian planet, analogous to recently discovered "hot Earths....

Water is essential for sustaining life on Earth. Almost 75% of the Earth’s surface is covered by it. It composes roughly 70% of the human body by mass [1]. It is the medium associated with nearly all microscopic life processes. Much of the reason that water can sustain life is due to its unique properties. Among the most essential and extreme properties of water is its capability to absorb larg...