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How glass is made from sand for children. How is opaque sand made into transparent glass? Glass making components

By name

by name


Merged or separate? Spelling dictionary-reference book. - M.: Russian language. B. Z. Bukchina, L. P. Kakalutskaya. 1998 .

See what "by name and patronymic" is in other dictionaries:

    by name- by name patronymic ... Russian spelling dictionary

    by name He calls me by my first name... Spelling Dictionary of the Russian Language

    by name- by and / me about / patronymic (call) ... merged. Apart. Through a hyphen.

    Appeal (naming) by name and patronymic

    address (naming) by name and patronymic- See anthroponymic formulas ...

    SURNAME- The name of a person by his father, the second of the three parts of the full Russian naming of a person (by name, patronymic and surname). It is formed from the basis of the name (see Russian names *) of the father with the help of the suffixes ovich / ovna, if formed from the name, ... ... Linguistic Dictionary

    Anthroponymic formulas- - formulas for naming a person, including appeals to him, including a component of his own name. Important question speech etiquette- the use of one or another anthroponymic formula in various situations. The most neutral and at the same ... ... Encyclopedic Dictionary of Psychology and Pedagogy

    anthroponymic formulas- formulas for naming a person, including appeals to him, including a component of his own name. An important issue of speech etiquette is the use of one or another anthroponymic formula in various situations. The most neutral and then ... ... Culture of speech communication: Ethics. Pragmatics. Psychology

    Magnifications- 1) festive formulaic glorifications (where the names change) of the Savior, the Mother of God and the saints, to which the chosen ones join. psalms are sung by the clergy in the middle of the temple (in front of the lectern with the icon of the corresponding holiday) at matins, after ... ... Russian humanitarian encyclopedic dictionary

    Surnames in the Russian nominal formula appeared rather late. Most of them came from patronymics (according to the baptismal or worldly name of one of the ancestors), nicknames (according to the type of activity, place of origin, or some other feature of the ancestor) ... Wikipedia

Books

  • Russia Cities People Traditions The Illustrated Encyclopedia, Korobkina T. (ed.). A book for foreigners studying Russian. The book is addressed to all those who are interested in Russia, its realities and traditions, who want to know Russian etiquette and want to learn how to lead…
  • Illustrated Encyclopedia: Russia. Cities, people, traditions, N. B. Karavanova. A book for foreigners studying Russian. The book is addressed to all those who are interested in Russia, its realities and traditions, who want to know Russian etiquette and want to learn how to lead…

Many of us face such a problem in everyday communication - how exactly should we address another person? Moreover, starting from the end of the 90s, the simplified address is increasingly used only by name (without patronymic). How should this be treated? When I was at school (now I am 30 years old), we were hammered into our heads that we should address the elders by their first name and patronymic and “you”, and they, since they are “senior” in relation to us, have every right not to only to address us simply by name and "you", but also using diminutive forms (for example, not Vladimir, but Vova). This was supposed to emphasize the difference in the age hierarchy, well known from the Soviet, and from pre-revolutionary times too. It doesn't matter who you are and what you have achieved in life, whether you have a mind or some positive qualities, the main thing is that you need to "listen" and "respect" your elders.

The last provision also implied that, in principle, it is not at all necessary to respect any person and his personal dignity, but only on the condition that this person is much older than you or has a certain profession / holds a certain position. Chiefs, officials, deputies, and more recently, priests (the same officials, only church ones) have always enjoyed special respect in our country - they are called “fathers” and “fathers” at all, although Christ, as you know, spoke on this subject completely. definitely: "But do not call yourself teachers, for one is your Teacher - Christ, yet you are brothers; and do not call anyone on earth your father, for you have one Father who is in heaven; and do not call yourself teachers, for one Christ is your guide" (Mt 23:8-10).

But if we ignore this husk and try to solve the problem in, so to speak, ideal conditions, then what should be an adequate appeal to other people? I will not undertake to answer for everyone, but for myself I chose the following strategy, consisting of 7 simple rules.
1. Initially, I address everyone as "you", except for very young children (up to 12 years old).
2. If they turn to me with "you", then I also turn to "you", but if this person does not cause me sympathy, then I try to minimize contact with him.
3. To everyone who addresses me simply by my first name, I also address simply by my first name (without a patronymic), regardless of how old he is and what his position is (I make an exception only for a few people who are attractive to me and who it has been too many years for them to wean themselves from certain stereotypes.
4. To everyone who addresses me by my first name and patronymic, I also address by my first name and patronymic (if I know it).
5. I use the address by name and patronymic only in business correspondence and in the public space certain conditions, but in everyday communication I prefer addressing by name, but on "you".
6. I allow diminutive forms of the name only in communication with close people and friends.
7. I have long noticed that any familiarity quickly turns into rudeness and an unacceptable violation of personal boundaries, so I still prefer to keep communication on "you" until I know the person better and get closer to him.

The names and faces of those worthy people who gave the world glass, history, as usual, did not bother to save. Actually, there is nothing surprising in this: according to the Roman historian Pliny the Elder, the Phoenician sailors were the discoverers. Moreover, the discovery, like most of his kind, was made by accident.

If we ignore the high style and ancient Latin in which Pliny's "Natural History" was written, the story is as follows. One day, a Phoenician merchant ship, caught in a strong storm, was forced to anchor in a small bay. Tired and chilled sailors went ashore. They began to look for a place to make a fire in order to cook their own stew and keep warm. The shore was sandy, and there were no stones to be seen anywhere on which to put a cauldron. Then it occurred to one of the sailors to pull out of the ship's hold blocks of soda, which were being transported for sale, and put a boiler on these blocks.

So, it was on these soda blocks that the Phoenician sailors put a cauldron of water. The fire turned out to be extremely successful. The sailors had a hearty meal and went to bed. In the morning, getting ready to go, one of them scattered the smoldering remains of a fire. Suddenly he noticed some shiny pieces in the ashes. They didn't look like wood, or metal, or clay, or stone. Until then, no Phoenician had seen such strange light pieces. This new mysterious substance - according to Pliny - was glass: an alloy of coastal sand with soda.

This story is likely to be remembered by everyone who read a history textbook in school. For some reason, this version is loved by many to this day. But how plausible is it? Alas, modern glass makers have quite convincingly proved that the ancient historian was mistaken. Or misrepresented something. But the fact remains: it is impossible to weld glass from soda and sand in a fire flame.

More realistic seems to be the assumption that, by chance, a mixture of sand and soda fell on a clay pot before firing. And the potter, who took the finished product out of the oven, noticed a thin shiny film that covered the sides of the vessel.

In general, one can only guess about who was lucky with the discovery of glass and either believe the stories about the Phoenician sailors, who were generally wonderful guys, or support the version of the lucky and attentive potter. Those who study the history of the origin of this material will someday come to a consensus regarding the place - Egypt, Phenicia or Mesopotamia, Africa or the Eastern Mediterranean, etc. - and regarding the time - "about 6 thousand years ago", but the characteristic "synchronism of discoveries » can be observed, and the difference even of hundreds of years does not matter much, especially when significant differences can be traced in the reconstructed method of melting glass.

Glass manufacturing technology

Who do you think is ahead of the rest in the field of ancient glassmaking? That's right - the ancient Egyptians. Until about 4 thousand BC. ancient egyptians the so-called "Egyptian faience" was brewed from steatite, soft quartz flour or whole natural quartz.

There is an opinion that the earliest samples are made of steatite. The composition of this mineral is magnesium silicate, it is present in nature in large quantities. Products cut from a piece of steatite were coated with a powder mixture of raw materials that make up the glaze and fired. This glaze, which in chemical composition is sodium silicate with a small admixture of calcium, is nothing more than fusible glass, painted in blue and greenish-blue tones with copper, sometimes with a fair amount of iron.

Egyptian glassmakers melted glass on open hearths in earthenware bowls. The sintered pieces were thrown hot into the water, where they cracked. The resulting fragments, the so-called frits, were ground to dust with millstones and melted again.

Fritting was used as the main glass-making technology even after the end of the Middle Ages, so in old engravings and archaeological excavations we always find two furnaces - one for pre-melting and the other for melting frits.

The required penetration temperature is 1450 °C and the operating temperature is 1100-1200 °C. The medieval melting furnace (“gut” - in Czech) was a low arch, heated by firewood, where glass was melted in clay pots. Laid out only from stones and alumina, it could not stand it for a long time, but for a long time there was not enough firewood. Therefore, when the forest around the guta was cut down, it was transferred to a new place where there was still plenty of forest.

Another furnace, usually connected to a smelter, was an annealing furnace - for tempering, where the finished product was heated almost to the point of glass softening, and then cooled rapidly to compensate for the stresses in the glass (prevent crystallization).

In the form of such a design, the glass furnace lasted until the end of the 17th century, however, the lack of firewood forced some Huts, especially in England, to switch to coal already in the 17th century. With the change of fuel, another inconvenience arose: the sulfur dioxide escaping from the coal stained the glass yellow. To avoid this, the British began to melt glass in the so-called covered pots.


Interesting information is that glass, in a general sense, has not undergone practically any changes during its existence (the earliest samples of what they began to call glass do not differ in any way from the bottle known to everyone), but in this case we are talking about a substance and material of mineral origin, which has found application in modern practice.

Glass composition

Pure silica (SiO2) has a melting point of approximately 2000 degrees and is mainly used to make glass for specialty instruments. Usually, two more substances are added to the mixture to simplify the production process. Firstly, it is sodium carbonate (Na2CO3), or potassium carbonate, which lowers the melting point of the mixture to 1000 degrees. However, these components contribute to the dissolution of glass in water, which is highly undesirable. Therefore, another component is added to the composition of the mixture - lime (calcium oxide, CaO) to make the composition insoluble. This glass contains about 70% silica and is called soda-lime glass. The share of such glass in the total production is approximately 90%.

Just like lime and sodium carbonate, other ingredients are added to ordinary glass to change it. physical properties. The addition of lead to glass increases the refractive index of light, significantly increases the brilliance, and the addition of boron to the composition of the mixture changes the thermal and electrical properties of the glass. Thorium oxide gave glass a high refractive index and low dispersion, which is necessary in the production of high-quality lenses, but due to its radioactivity was replaced by lanthanum oxide in modern products. Iron additives in glass are used to absorb infrared radiation(heat).

Metals and their oxides are added to glass to change its color. For example, manganese is added in small amounts to give the glass a green tint, or at higher concentrations, an amethyst color. Like manganese, selenium is used in small doses to discolor glass, or in high concentrations to impart a reddish color. Small concentrations of cobalt give the glass a bluish tint. Copper oxide gives turquoise light. Nickel, depending on the concentration.

In addition to ordinary glass, there are several varieties of historical, cultural and artistic value. For example, Czech and Murano glass. But about them - in the following materials. Follow the news.

Glassware, windows in houses and much more - for us today these are familiar furnishings. However, many centuries ago, glass goblets were fabulously expensive, and they could only be found on the tables of the richest and noblest nobles.


What is glass made of, and how did people learn to make it?

History of the invention of glass

Glass has been known for at least two thousand years. The ancient Roman historian Pliny described the incident as a result of which it was invented. According to his version, once sailors carrying soda on their ship landed to spend the night on a shore covered with pure golden sand.

They lit a fire to cook dinner and keep warm. By chance, one sack of their cargo burst open and spilled the soda into the fire. At night it began to rain, washed away the ashes and firebrands, and the sailors saw a shining glass surface in place of the fire.

Glass making components

Whether glass was actually invented, or, as another version says, it was obtained in the course of experiments with firing clay pots - but people have mastered the secret of its preparation for a long time.

In order to make glass, three main components are required.

Quartz sand- This is pure river sand, consisting of silicon oxide. The proportion of sand in the mixture for melting glass is about 75%. It melts at very high temperature: It needs to be heated to 1700 degrees Celsius. The transparency and quality of future glass products largely depend on the quality of the sand. Venetian glassblowers, who made the most famous in medieval Europe Murano glass, sand was specially brought from the province of Istria, and for Bohemian glass, craftsmen crushed pieces of quartz into fine sand.

Soda (or potash) needed to melt the sand at a lower temperature. By adding soda to the sand in the right proportion, the heating temperature of the glass mixture is reduced by almost half.


During heating, soda decomposes to sodium or potassium oxide, which serves as a melting catalyst. In ancient times, it was obtained by leaching ash after burning algae or coniferous trees. The proportion of soda in the mixture for glass is about 16-17%.

Lime, or calcium oxide, makes glass insoluble by most chemicals, strong and shiny. For the first time, Bohemian glassblowers began to add it to glass in the seventeenth century, using limestone or chalk for this.

In addition, today sodium sulfate, talamite and nepheline syenite are added to the mass for making glass. To obtain multi-colored glass, oxides of various metals are used as additives: copper, iron, silver, etc.

Stages of sheet glass production

All the ingredients from which glass is made are loaded into a furnace and heated until a liquid homogeneous mass is formed.

The molten mass is loaded into a homogenizer and mixed until completely homogeneous.

The glass mass is poured into a long container containing molten tin. On its surface, the glass is poured in an even layer of the same thickness, gradually cooling down.

The frozen glass tape enters the conveyor, where the thickness control and cutting into standard pieces of glass is carried out. Cropped jagged edges and rejects that have not passed quality control are sent for remelting.

Finished sheet glass passes the final quality check and is sent to the warehouse finished products.

Similarly, glass is made for the production of dishes, measuring instruments, Christmas decorations and other products. The composition of the glass may vary depending on the properties it is intended to have.

In addition, to increase strength, it can be subjected to a hardening procedure, acquiring the ability to withstand strong impacts on the surface.


Popular today are duplex and triplex glass, glued with special compositions of two or three layers of thin glass. However, the basis of each of them is golden quartz sand, baking soda and ordinary lime.

Why do we need furnaces for glass melting? The fact is that in order to make something useful out of glass, you must first melt it, and it melts at temperatures of neither more nor less, 1400-1600 ° C.

The raw material for the manufacture of glass is mainly quartz sand (silicon oxide SiO2)


Quartz sand

To give the glass the necessary properties, quartz sand is mixed with various additives, mainly limestone (the one that is shell rock, from the facades of buildings), feldspar, dolomite, soda and dyes (metal oxides)


Limestone


Feldspar


Dolomite

Such additives in glass can be up to 20-30%. In general, the more additives, the lower the viscosity of the melt (roughly speaking, it is “fluid”) and the lower the melting point, i.e. it is easier to process, for example, blowing bottles, etc. is already possible at 800 ° C. But it can be different: if, for example, boron oxide is added to the mixture, borosilicate glass will come out, heat-resistant and resistant to temperature extremes - to the delight of housewives. Glass made of pure silicon oxide will turn out to be refractory; in order to blow something out of it, it will be necessary to heat it up to 1600 ° C.

In general, we sorted out the raw materials. Everything that is needed is thoroughly cleaned, crushed (usually special concentrating factories / productions are engaged in this), mixed and poured into a glass furnace through a special window. Inside the furnace in a huge pool, almost infernal fire takes over and turns sand into liquid in a few hours.

Flame inside the oven.

By the way, stoking such a furnace to the desired temperature is a difficult, long, and most importantly, expensive process (how much fuel is needed to heat up such a huge fool for 2-9 thousand tons of glass!), therefore, having ignited it once, they try not to extinguish it anymore: the process of glass melting for 10-15 years of furnace service is interrupted only a couple of times for cold repairs.

Naturally, the mixture does not melt all at once, but gradually; as it melts, it mixes, air bubbles come out of it. What has already melted well is collected at the bottom of the pool (the density of the melt is higher) and, according to the law of communicating vessels, flows under the wall passing through the pool to another part of it, away from the flame and the mixture that has not yet been melted.

Here the temperature is a little lower, and liquid glass from here it enters the next, working bath outside the furnace, and from there it goes for processing. To obtain, for example, sheet glass for windows and mirrors, it is cast and rolled almost like metal.

In order to obtain a perfectly flat surface, in modern factories, molten glass is first poured into a pool full of molten tin, and it, the glass, floating on the surface of the tin, is distributed over it in a uniform thin layer and cools from about 1000 to 600 ° C, so the so-called float glass (float-glas).

As I said, this process is continuous, and the output after cooling is an endless glass ribbon. But before it is cut into pieces, the surface is heated again with gas burners: in this way, microcracks are sealed, which still form even despite gradual cooling due to the difference in stresses inside the glass during hardening. As a result, the glass comes out especially transparent.


Float glass production

The old technology, used in Soviet factories, provided for the vertical drawing of a glass ribbon with intensive cooling of the mass coming from the furnace. Glass produced in this way is characterized by significantly higher optical distortions.

Well, it looks like almost everything is sorted out. In the picture, only one more incomprehensible part of the furnace remained: the regenerator. The contraption is wonderful and ingenious in its simplicity. For its invention back in 1856, the youngest of the Siemens brothers, Friedrich, received the English nobility. And the point is to save fuel for the glass melting furnace by heating the air supplied to the combustion furnace. And you can save up to 40% on fuel!


The principle of operation of the regenerator

The regenerator consists of two identical shafts filled with heat-resistant ceramic assemblies, which form many small air channels inside the shafts. Air enters through the first shaft, enters the furnace through the window, mixes with fuel (gas) and burns. The hot products of combustion go through another window into the second shaft, and before going outside, the mentioned ceramic assemblies are heated. Then, as soon as they are sufficiently heated, after about twenty minutes, the air flow is let through the second shaft, it is heated in it before entering the furnace, and the exhaust gases begin to heat up the assemblies in the first shaft. Then the cycle repeats.

Outside of this story, there were various heat-resistant ceramic coatings inside the furnace (metal is not suitable for such a temperature). With them, everything is also quite entertaining: the physical and chemical processes that occur during the melting of glass lead to amazing formations: stalactites begin to grow inside the furnace!

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