Science and technology

Two hydrogens can form a diatomic molecule H2, which exists in gaseous form at room temperature and is therefore referred to as hydrogen. Hydrogen molecules are composed of covalent bonds, and the modern theory of covalent bonds begins with quantum mechanical studies of hydrogen molecules. Hydrogen is a clean energy source that combines with oxygen to release a lot of heat. At the same quality, the heat released by hydrogen combustion is more than four times that of coal, and its reaction product is water, which is harmless to the environment...

3D printing, a new type of manufacturing technology, is receiving more and more attention. Conventional manufacturing techniques generally process a single piece of material into the required size and...

First, we have to figure out what the background radiation is. Many people may first think of these four words as the concept of physics "cosmic background radiation" or "universe microwave background radiation." In fact, background radiation, also known as background radiation, is a concept in the field of radiation safety and protection. We know that radiation can be divided into ionizing radiation and non-ionizing radiation according to whether it can ionize atoms and molecules. The former includes particles such as α particles, β particles, neutrons, etc...

When it comes to glue or adhesive, the first thing that everyone thinks of is the glue that is contained in the small bottle. When it is used, it can be applied to the object to be bonded. However, some adhesives are separately contained in two containers, and the two parts must be mixed evenly before use, otherwise, they will not work. Such an adhesive is commonly known as AB glue. AB glue is much more complicated in form than ordinary adhesives, and it is more troublesome to use. So why do we develop...

There is a "Chicago school" in the economics field. They believe that everyone is very rational when making choices. They will definitely make their own decisions. Therefore, the government should not interfere with individual freedom and let people freely choose what they want. lifestyle. This school is very influential in the economics field and is the theoretical basis of "neoliberalism." However, there have been people who have questioned this theory and accused it of overestimating human judgment...