Tears of Gratitude 6th Grade Essay 450 Words Today to hurry up and be quick and good with additional

From fireflies to artificial cold light.

Since the invention of electric light, life has become much more convenient and richer. But electric light can only convert a small part of the electrical energy into visible light, and most of the rest is wasted in the form of heat, and the heat rays of electric lights are harmful to the human eye. So, is there a light source that only emits light but does not heat up?

Humanity has turned its attention to nature again.

In nature, there are many organisms that can emit light, such as bacteria, fungi, worms, mollusks, crustaceans, insects and fish, etc., and the light emitted by these animals does not produce heat, so it is also called "cold light".

Among the many light-emitting animals, fireflies are one of them. There are about 1,500 species of fireflies, and the colors of their cold light range from yellow-green to orange, and the brightness of the light varies. The cold light emitted by fireflies not only has a high luminous efficiency, but also the cold light emitted is generally very soft, which is very suitable for human eyes, and the intensity of the light is relatively high.

Therefore, biolight is a kind of light that is ideal for human beings.

Scientists have found that the glowing device of the firefly is located in the abdomen. This luminaire is composed of three parts: a light-emitting layer, a transparent layer and a reflective layer. The luminescent layer has thousands of light-emitting cells, and they all contain two substances, luciferin and luciferase.

Under the action of luciferase, luciferin fluoresces when it is oxidized with the participation of intracellular water. The luminescence of fireflies is essentially the process of converting chemical energy into light energy.

Back in the 40s, fluorescent lamps were created based on the study of fireflies, which changed the source of human lighting a lot. In recent years, scientists have isolated pure luciferin from the luminescent device of fireflies, and later isolated luciferase, and then chemically synthesized fluorescein. A biological light source composed of a mixture of luciferin, luciferase, ATP (adenosine triphosphate) and water, which can be used as a flash lamp in mines filled with ** gas.

Since this light has no power source and does not generate a magnetic field, it can be illuminated by a biological light source to remove magnetic mines.

Nowadays, people can use the method of mixing certain chemicals to obtain cold light similar to biological light, which is used as safety lighting.

Sun rain. — Tears of gratitude.

When clouds and cold winds last only until dawn.

When thunder and lightning and heavy rain began again in the evening.

I know. Heaven is sentient.

Because it knows.

Having a son needs a sunny day.

Accompany his mother to play.

When my mother and I walked through the park.

When I first experienced solar rain.

I know. Heaven is a dutiful son-

Because on Mother's Day.

He put the most sincere tears.

Dedicated to his mother.

Put on a sunny day.

It was given to the mother of the whole world.