Menu English Ukrainian russian Home

Free technical library for hobbyists and professionals Free technical library


BIG ENCYCLOPEDIA FOR CHILDREN AND ADULTS
Free library / Directory / Big encyclopedia for children and adults

What age can be considered Balzac? Detailed answer

Big encyclopedia for children and adults

Directory / Big encyclopedia. Questions for quiz and self-education

Comments on the article Comments on the article

Did you know?

What age can be considered Balzac?

The expression "Balzac's age" arose after the release of Balzac's novel "The Thirty-Year-Old Woman" and is permissible in relation to women no older than 40 years.

Authors: Jimmy Wales, Larry Sanger

 Random interesting fact from the Great Encyclopedia:

What is metal?

It is not so easy to give an exact answer to the question: "What is a metal?" In terms of physical properties, a metal is a substance that has a bright luster and good conductivity of heat and electricity. However, these properties can also have substances that are by no means metals.

Metals differ greatly from each other in hardness, density, malleability and malleability. (Ductility means the ability to work metal with blacksmith hammers or presses, and malleability means drawing it into wire.) Each metal has a specific melting point, as well as the ability to form alloys with other metals.

At normal room temperature, all metals except mercury are solids. Some metals (for example, gold) can sometimes be found in nature in pure form, but most of them exist in natural conditions only in the form of compounds with other elements. Most often they occur in the form of sulfides, oxides, carbonates and silicates, usually with impurities of granite and other rocks. Many metals are found in ores in combinations with each other. These include lead, zinc, iron, copper, chromium, nickel and others.

Some of the metals are so rare in nature that in order to obtain a very small amount, for example, pure rhenium radium, it is sometimes necessary to process tens of tons of ore. The branch of industry engaged in obtaining pure metals and their alloys from natural raw materials is called metallurgy. Many metals in their pure form have properties that make it difficult to use them for one purpose or another. That is why most of them are used in the form of alloys or chemical compounds. For example, pure iron has insufficient hardness.

Therefore, as a rule, it is used in the form of steel, which is its compound with carbon, often with the addition of other metals: chromium, tungsten, vanadium, etc. Some metals are necessary for the existence of living beings. These include iron, calcium, sodium, magnesium and potassium. Even copper, aluminum and manganese, however, in very tiny amounts, are required for the normal development of the body.

 Test your knowledge! Did you know...

▪ Which stars are closest to Earth?

▪ Who has screwed horns?

▪ Why don't hedgehogs, contrary to children's drawings, carry apples on their backs?

See other articles Section Big encyclopedia. Questions for quiz and self-education.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Solidification of bulk substances 30.04.2024

There are quite a few mysteries in the world of science, and one of them is the strange behavior of bulk materials. They may behave like a solid but suddenly turn into a flowing liquid. This phenomenon has attracted the attention of many researchers, and we may finally be getting closer to solving this mystery. Imagine sand in an hourglass. It usually flows freely, but in some cases its particles begin to get stuck, turning from a liquid to a solid. This transition has important implications for many areas, from drug production to construction. Researchers from the USA have attempted to describe this phenomenon and come closer to understanding it. In the study, the scientists conducted simulations in the laboratory using data from bags of polystyrene beads. They found that the vibrations within these sets had specific frequencies, meaning that only certain types of vibrations could travel through the material. Received ... >>

Implanted brain stimulator 30.04.2024

In recent years, scientific research in the field of neurotechnology has made enormous progress, opening new horizons for the treatment of various psychiatric and neurological disorders. One of the significant achievements was the creation of the smallest implanted brain stimulator, presented by a laboratory at Rice University. Called Digitally Programmable Over-brain Therapeutic (DOT), this innovative device promises to revolutionize treatments by providing more autonomy and accessibility to patients. The implant, developed in collaboration with Motif Neurotech and clinicians, introduces an innovative approach to brain stimulation. It is powered through an external transmitter using magnetoelectric power transfer, eliminating the need for wires and large batteries typical of existing technologies. This makes the procedure less invasive and provides more opportunities to improve patients' quality of life. In addition to its use in treatment, resist ... >>

The perception of time depends on what one is looking at 29.04.2024

Research in the field of the psychology of time continues to surprise us with its results. Recent discoveries by scientists from George Mason University (USA) turned out to be quite remarkable: they discovered that what we look at can greatly influence our sense of time. During the experiment, 52 participants took a series of tests, estimating the duration of viewing various images. The results were surprising: the size and detail of the images had a significant impact on the perception of time. Larger, less cluttered scenes created the illusion of time slowing down, while smaller, busier images gave the feeling of time speeding up. Researchers suggest that visual clutter or detail overload can make it difficult to perceive the world around us, which in turn can lead to faster perception of time. Thus, it was shown that our perception of time is closely related to what we look at. Larger and smaller ... >>

Random news from the Archive

Solar Powered Wireless Sensor Module 29.07.2005

The German company Startup EnOcean GmbH offers a wireless sensor module powered by solar cells.

The STM100 module contains three analog and two digital inputs for connecting sensors, an embedded microprocessor, a radio frequency (RF) transceiver, a two-stage (two-stage) solar panel and an energy storage device. The dimensions of the module are 2x20x40 mm, it can work both indoors and outdoors with a minimum illumination of 10 lux. For comparison, the typical level of illumination in the halls of buildings is 200 lux, on the desktop - 200 lux.

The energy reserve is enough to work for five days in complete darkness. The power of the RF transmitter is 50 μW, the range is 300 meters (indoors through walls). The signal is transmitted in short (about 1 μs) pulses (packets). The module supports several types of sensors, including sensors for measuring humidity, illumination, position and pressure. The cost of the STM100 module is $25 in industrial lots.

Other interesting news:

▪ Nanolaser for photonics

▪ A black hole cannot become heavier than 50 billion suns

▪ Synthesis of bones and enamel

▪ Ventilator to help you breathe

▪ Refrigerator for quantum chips

News feed of science and technology, new electronics

 

Interesting materials of the Free Technical Library:

▪ site section Batteries, chargers. Article selection

▪ article Clinical psychology. Crib

▪ What is the difference between papyrus and parchment? Detailed answer

▪ article Universal stud driver. home workshop

▪ UMZCH article with an output stage on field-effect transistors. Encyclopedia of radio electronics and electrical engineering

▪ article Application of medium power solid-state optoelectronic relays. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

Name:


Email (optional):


A comment:





All languages ​​of this page

Home page | Library | Articles | Website map | Site Reviews

www.diagram.com.ua

www.diagram.com.ua
2000-2024