For the first time in 100 years, Atlantic salmon are once again spawning in the upper waters of the River Derwent.
Plants & Animals
Apr 10, 2024
0
8
Engineering structures made of concrete, steel, or other materials are subject to vibrations and stress. Because of this, small cracks appear, which grow and eventually lead to destruction. This phenomenon is called "fatigue ...
Polymers
Jan 16, 2024
0
2
We know that war is bad for the environment, with toxic chemicals left polluting the soil and water for decades after fighting ceases. Much less obvious are the carbon emissions from armed conflicts and their long-term impacts ...
Environment
Dec 13, 2023
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6
Earth's average temperature in September 2023 was 1.75°C above its pre-industrial baseline, breaching (if only temporarily) the 1.5°C threshold at which world leaders agreed to try and limit long-term warming.
Plants & Animals
Oct 21, 2023
1
89
With a light flick of the conductor's baton and a unified breath from each member, the band started playing the two deep and ominous notes easily recognized as the theme of "Jaws." The sounds echoed off the walls of the acoustics ...
Space Exploration
Jun 30, 2023
0
4
On the morning of February 6, 2023, a very strong earthquake with a magnitude of 7.8 hit an area in south central Turkey and northwestern Syria. About nine hours later, another powerful earthquake measuring 7.5 struck a nearby ...
Earth Sciences
Jun 21, 2023
0
5
The first piece of a series of concrete structures was lowered into the water off the coast of Miami Beach on Wednesday morning, a massive crane on the deck of a floating barge hoisting the unit into the air and sinking it ...
Ecology
Mar 6, 2023
0
50
There is no good place to be when a nuclear bomb goes off. Anything too close is instantly vaporized, and radiation can pose a serious health threat even at a distance. In between, there is another danger: the blast wave ...
General Physics
Jan 17, 2023
4
179
Racist segregation housing practices in the U.S. have had a genetic impact on urban wildlife, a new study by University of Manitoba in the Proceedings of the National Academy of Sciences reports.
Ecology
Oct 19, 2022
0
30
Seeing a larger number of species on urban coastlines—from marine animals to seaweed—is likely to improve the well-being of local people and visitors, new research from a team at Swansea University has revealed. The findings ...
Ecology
May 11, 2022
0
18
Concrete is a construction material composed of cement (commonly Portland cement) as well as other cementitious materials such as fly ash and slag cement, aggregate (generally a coarse aggregate such as gravel, limestone, or granite, plus a fine aggregate such as sand), water, and chemical admixtures. The word concrete comes from the Latin word "concretus" (meaning compact or condensed), the past participle of "concresco", from "com-" (together) and "cresco" (to grow).
Concrete solidifies and hardens after mixing with water and placement due to a chemical process known as hydration. The water reacts with the cement, which bonds the other components together, eventually creating a stone-like material. Concrete is used to make pavements, architectural structures, foundations, motorways/roads, bridges/overpasses, parking structures, brick/block walls and footings for gates, fences and poles.
Concrete is used more than any other man-made material in the world. As of 2006, about 7.5 cubic kilometres of concrete are made each year—more than one cubic metre for every person on Earth. Concrete powers a US $35-billion industry which employs more than two million workers in the United States alone.[citation needed] More than 55,000 miles (89,000 km) of highways in the United States are paved with this material. Reinforced concrete and prestressed concrete are the most widely used modern kinds of concrete functional extensions.
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