The oldest metal objects found in the Middle East are made of copper; It's a small awl, dating back to 5 100 BC. American coins were originally pure copper (although now the zinc content is 97.5% and the copper skin is very thin).
According to the data of the US Geological Survey, copper is the third largest consumer metal in the world, second only to iron and aluminum. Besides gold, about three-quarters of copper is used to make wires, telecommunication cable and electronic products.
Copper is the only metal in the periodic table whose color is not natural silver or gray.
Chemical description Atomic number (number of protons in the nucleus): 29 Atomic symbol (on the periodic table of elements): Atomic weight of copper (average mass of atoms): 63.55 Density: 8.92g per cubic centimeter. At room temperature: solid melting point: 1984.32 degrees Fahrenheit (1084.62 degrees Celsius) boiling point: 53065438. 2 The history and characteristics of the most common stable isotopes: copper -63(69. 15% natural abundance) and copper -65(30.85% natural abundance). Most copper exists in ore, and it must be smelted or extracted from ore to obtain purity before use. However, according to the data of Chemicool, a chemical database website, natural chemical reactions sometimes release natural copper.
Humans have been making things with copper for at least 8000 years, and discovered the method of smelting copper around 4500 BC. The next technological leap is to make copper alloys by adding tin to copper, which creates a metal harder than a single part: bronze. Technological development ushered in the Bronze Age, covering about 3300 to 1200 years, and the use of bronze tools and weapons in history. Archaeologists found a small awl, or pointed tool, in an ancient village in Israel, dating back to 5 100 BC. It was buried with a middle-aged woman. This awl represents the oldest metal object found in the Middle East. According to the article published on 20 14, the copper may come from the Caucasus, located in the mountainous areas of southeastern Russia, Armenia, Azerbaijan and Georgia, 600 miles away (1000 km). In ancient Egypt, people used copper alloy to make jewelry, including toe rings. According to the US Geological Survey, researchers also discovered a large number of copper mines in Israel in the 10 century BC.
About two thirds of the copper on the earth exists in igneous rocks (volcanic rocks) and about one quarter in sedimentary rocks. This metal has ductility, good thermal conductivity and electrical properties, which is why copper is widely used in electronics and wiring. "kdspe" and "kdsps" copper turn green due to oxidation reaction; In other words, when exposed to water and air, copper will lose electrons. The copper oxide produced is dark green. This oxidation reaction is the reason why the copper-plated Statue of Liberty is green rather than orange-red. According to the copper development association, the copper oxide in the weathered layer is only 0.005 inch (0. 1.27 mm) thick, and the covering layer weighs about 80 tons (73 metric tons). According to the historical society of new york, the change from bronze to green occurred gradually, which was completed in 1920, that is, 34 years after the statue was presented and unveiled?
Here are some interesting facts about copper:
According to Peter van der Krogt, a Dutch historian, the word "copper" has several roots, many of which come from Latin cuprum, which means that Todd was the first person to prove that it may have clinical benefits. The researchers didn't change anything in the ICU except copper; Doctors and nurses still wash their hands and clean as usual. The researchers published their findings in the 20 13 issue of Infection Control and Hospital Epidemiology. According to an article published in the American Journal of Infection Control on 20 17, the researchers found that the number of bacteria in copper-plated stethoscopes was significantly reduced, and 66% stethoscopes were completely free of bacteria. Further research is continuing to test the idea of copper plating in other medical wards, especially in areas where patients are more mobile than ICU. She said that a cost-benefit analysis is also needed to weigh the cost of installing copper cables against the cost saved by preventing high-cost infection. She said:
Electronic products: Copper also plays a huge role in electronic products. Because of its abundant and low price, Michael Cheng, a professor of chemical engineering at Monash University in Australia, said that researchers are trying to integrate this metal into more and more sophisticated equipment.
In fact, copper may help to produce future electronic paper, wearable biosensors and other "soft" electronic products. Zheng He and his colleagues used copper nanowires to create an "aerogel monolith", which is highly porous, very light and strong enough to stand independently, similar to a dry kitchen sponge. In the past, these aerogels were made of gold or silver, but copper was a more economical choice. "kdspe" kdsps is a mixture of copper nanowires and a small amount of polyvinyl alcohol. Researchers have made gas gel, which can be turned into conductive rubber, with conductivity and formability. The researchers reported their findings in the 20 14 ACS nano-journal. Cheng told Life Science that the end result may be a robot with a soft body or a medical sensor that can perfectly blend into curved skin. He and his team are currently making blood pressure and temperature sensors with copper aerogel blocks, which is another way that copper helps monitor human health.
Physics: In an experiment in 20 14, when researchers cooled a large piece of copper to 6 millikelvin, that is, one thousandth of a degree above absolute zero (0 Kelvin), it became the coldest cubic meter (35.3 cubic feet) on earth. This is by far the closest thing to absolute zero in mass and volume. Italian National Institute of Nuclear Physics
The researchers put 880 pounds (400 kilograms) of copper cubes into a container called a cryostat, which is specially designed to keep things extremely cold. This is the first cryostat, or cryogenic storage device, which can keep substances near absolute zero.
Building a cryostat with extreme temperature is only the first step in the new experiment of cryostat as a particle detector. The researchers hope that according to the latest situation of 20 18, the detector being debugged can reveal more information about subatomic particles called neutrinos, and why there are much more substances in the universe than antimatter.
Agriculture: Cornell University researchers have been studying the effects of copper on crops, especially wheat. Wheat is one of the most important staple foods in the world, and the lack of copper will lead to the decrease of crop yield and crop fertility.
Researchers have been studying how plants absorb and process copper. According to the USDA, they found two kinds of protein AtCITF 1 and AtSPL7 in wheat, and these two kinds of protein are very important for wheat reproductive organs to absorb and transfer copper.
Early experiments showed that when copper and other nutrients were enriched in soil and then absorbed by wheat, the crop yield increased by as much as seven times. Although people know that knowledge of copper and other minerals is beneficial to the health and fertility of crops, the way and reason of this fact are still unclear. Knowledge about why copper is beneficial and its role in plant growth and reproduction can be further applied to crops such as rice, barley and oats, and mineral-rich fertilizers, including copper, can be provided to these crops. For soils that were once unsuitable for farming,
Other resources The American Cancer Society examined the research on copper and claimed that it might have a role in preventing or treating cancer. The Environmental Protection Agency provided information about exposure to high concentrations of copper and the effects of copper corrosion in domestic pipelines. Thomas Jefferson National Accelerator Facility (Jefferson Laboratory) explored the history and uses of copper. "This article was updated by Rachel Ross, a writer of Life Science, on September 20th18th12nd. "