What are the derivatives of the skin. What is the skin made of. Functions, features and structure of the sebaceous, sweat and mammary glands. How do sweat and mammary glands differ and what do they have in common, how do they develop in men and women. What are human hair and nails made of?
Science 2024, November
When calculating amplifying stages on semiconductor elements, you need to know a lot of theory. But if you want to make the simplest ULF, then it is enough to select transistors for current and gain. This is the main thing, you still need to decide in which mode the amplifier should work - it depends on where you plan to use it. After all, you can amplify not only sound, but also current - an impulse to control any device
In induction furnaces and devices, heat in a heated device is released by currents arising in an alternating electromagnetic field inside the unit. They are called induction. As a result of their action, the temperature rises
The rapid development of petrochemistry began in the 30s. 20th century The dynamics of development can be estimated by the volume of world production (in million tons): 1950 - 3, 1960 - 11, 1970 - 40, 1980 - 100! In the 1990s, petrochemicals accounted for more than half of the world's organic production and more than one third of the entire chemical industry
Forecasting stages: definition, goals and methods of developing a forecast. Models used to describe processes. Brief description of the stages of forecasting: task setting, analysis of conditions, examination and choice of model, verification and implementation
Innovation cycles: definition of this concept, enlarged phases, stages and stages. A brief description of the work carried out at various stages. Management of innovation cycles at the state level and within a particular enterprise
What are the characteristics of modern society? The question is not easy, but if we talk about it globally and generally, we get a very solid answer. The modern social system is based on a post-industrial, information and legal society, in which knowledge, technology and science play a fundamental role. A modern person must be cultured and educated both in the humanitarian and in the technical sense
What is observation? This is a research method that is used in psychology for an organized and purposeful perception and study of an object. It is used where the intervention of the observer can disrupt the process of interaction of the individual with the environment. This method is especially needed when you need to get a complete picture of what is happening and understand people's behavior
Aristotle: his main philosophical concepts and contributions to science. What does "Man is a political animal" mean? How to understand this definition in the context of Aristotle's philosophy? Interesting facts from the life of a philosopher
Vasily Dokuchaev is a Russian geologist who has reached special heights in soil science. From this article you will get acquainted with the biography of the scientist and his main achievements
Electricity is a stream of particles moving in a certain direction. They have some charge. In another way, electricity is the energy that is obtained during movement, as well as the lighting that appears after receiving energy. The term was introduced by the scientist William Gilbert in 1600
One of the hallmarks of Venus is the special nature of its magnetic field. To the question of whether Venus has a magnetic field, there is the following answer: the planet has practically no own field, but due to the interaction of the solar wind with the atmosphere, an induced field arises
The Higgs boson is the most expensive particle of all time. If, for example, a vacuum tube and a couple of brilliant minds were enough to discover the electron, the search for the Higgs boson required the creation of experimental energies that are rarely seen on planet Earth
Today we will look at some calcium compounds with hydrogen and carbon - calcium carbonate, hydroxide and calcium bicarbonate
The snake is the only composite asterism. In the sky, it occupies 23rd place out of 88 constellations in the area of u200bu200bthe observed sky. The brightest star of the Serpent is Unukelhaya
Many must have often heard the word "ampere", instantly referring this concept to physics. An ampere is a unit of measure for the strength of an electric current. But have you ever wondered why and in whose honor the unit of current strength was named? Today we will present information about the biography of André Marie Ampère, an outstanding physicist and brilliant scientist
Everyone knows the fact that a person is almost 80% water. But few people know that our he alth and well-being depend on the quality of this water
Magnetic field is a very interesting phenomenon. Currently, its properties have found application in many areas. Do you know what is the source of the magnetic field? After reading the article, you will know about it. In addition, we will talk about some facts related to magnetism
Amphoteric hydroxides are inorganic compounds capable of exhibiting acidic and basic properties depending on the nature of the substance with which they react. Dual properties are shown by metals of group A - Be, Al, Ga, Ge, Sn, etc. and group B - Cr, Mn, Fe, Zn, etc
Tungsten is a chemical element whose atomic number is 74. This heavy metal, from steel gray to white, is highly durable, which makes it simply irreplaceable in many cases
Every parent wants their children to be happy and find their place in life. Additional classes in music, dancing, sports, foreign languages - moms and dads are ready for anything so that their child is a comprehensively educated person. In itself, such zeal is commendable, but if the child does not "draw" on the ideal image? Here you need to look at the inclinations and interests of the baby and develop them. Help in choosing the right one can be provided by Howard Gardner's theory of multiple intelligences
Summary of theories about the essence of narratives in various humanitarian fields: in psychology, philology, philosophy, sociology and others. Description of the most significant terms related to the concept of narrative
On the outskirts of our star system is the Kuiper belt. It passes beyond the orbit of Neptune, so it was extremely difficult to see anything in this space before. However, since powerful telescopes have appeared at the disposal of man, several discoveries have been made. So, for example, it became known that the trans-Neptunian object is the main unit that makes up the Kuiper belt, the Oort cloud and the scattered disk. It is worth taking a closer look at the bodies rotating in the "backyard" of the solar system
Any star - yellow, blue or red - is a hot ball of gas. The modern classification of luminaries is based on several parameters
Characterization of celestial bodies can be very confusing. Only stars have apparent, absolute magnitude, luminosity and other parameters. We will try to deal with the latter. What is the luminosity of stars? Does it have anything to do with their visibility in the night sky? What is the luminosity of the Sun?
The astronomical unit, which has developed in the course of history, is a unit of distance measurement in astronomy - the science of the Universe. It is mainly used to determine the distance between various objects in the solar system, but its value is also used in the study of extrasolar systems
Rigel is a star that has amazed people with its beauty since ancient times. In Egypt, she was identified with the god of the dead and the patron of the starry sky Sakh, and later with Osiris. Rigel is part of the constellation Orion, one of the most visible celestial drawings
In 2009, the Kepler astronomical telescope was launched. The planet, the discovery of which is waiting for the whole world, inhabited by life, preferably intelligent. Are scientists' expectations realistic or will they remain just expectations? Perhaps, thanks to the space telescope, we will soon find out about this
There are many hypotheses and theories in geology. Tectonics is a relatively young science, the subject of which is lithospheric plates
Signal is a material carrier of information and a physical process in nature. Level, value and time as the main parameters of the signals. Relationship between the signal and their spectrum through the Fourier transform. RF and digital signal analyzers
One of the most important milestones in the history of the planet is the invention of electricity. It is this discovery that helps to develop our civilization to this day. Electricity is one of the most environmentally friendly types of energy. Who owns the discovery of this phenomenon? How is electricity produced and used? Is it possible to create a galvanic cell yourself?
Colligative properties of solutions are properties that do not depend on the nature of the solute, but are determined only by the concentration and nature of the solvent
Ionic bond - a chemical bond carried out by the electrostatic attraction of ions. It has no direction and saturation
Richard Phillips Feynman (years of life - 1918-1988) - an outstanding physicist from the USA. He is one of the founders of such a direction as quantum electrodynamics. Between 1943 and 1945, Richard was involved in the development of the atomic bomb. He also created the path integration method (in 1938), the Feynman diagram method (in 1949)
As you know, mathematics is the mother of all sciences. And this is no wonder. Since all the exact sciences are focused on calculations. However, this does not mean at all that everything in this kingdom is boring and boring. By no means! Despite the seriousness of the teaching, surprising and interesting facts about mathematics appear. And you can find them almost anywhere in the world
John Glenn, the first American to orbit the Earth, made history for the second time when, at the age of 77, he became the oldest person in space. But before the astronaut was recognized as a national hero, he risked his life more than once for his country
What is the distance from Earth to Saturn and how much time does it take a person to overcome this monstrous number of kilometers?
According to the definition in physics, the concept of "vacuum" implies the absence of any substance and elements of matter in a certain space, in this case one speaks of an absolute vacuum. A partial vacuum is observed when the density of the substance in a given place in space is low. Let's take a closer look at this issue in this article
In recent decades, large volcanic eruptions have become more frequent. This gives food for talk that a certain global cataclysm is approaching, which will lead, if not to the total extinction of all living things, then, in any case, to a significant reduction in populations
The discoveries of the outstanding scientist Svante Arrhenius became the basis of modern physical chemistry. The name of this researcher is primarily associated with the theory of electrolytic dissociation, however, this diversified person also de alt with other issues. Thanks to him, the capital of Sweden at the end of the 19th century. revived its glory as a major center of chemical science