How many and what kind of chemical monuments are known? From the history of chemical language. The most explosive substance

Municipal budgetary educational institution "Secondary school No. 4" in Safonovo, Smolensk region Project The work was carried out by: Ksenia Pisareva, 10th grade Anastasia Strelyugina, 10th grade Supervised the work by: Natalya Ivanovna Sokolova, teacher of biology and chemistry 2015/2016 academic year Project Theme "Chemical substances used in architecture" Project typology: abstract individual short-term Purpose: integration on the topic "Architectural Monuments" of the subject "World Artistic Culture" and information about chemical substances used in architecture. Chemistry is a science associated with many fields of activity, as well as with other sciences: physics, geology, biology. It did not bypass one of the most interesting types of activity - architecture. A person working in this field inevitably has to deal with different types of building materials and somehow be able to combine them, add something to them for greater strength, durability, or to give the most beautiful appearance to the building. To do this, architecture needs to know the composition and properties of building materials, it is necessary to know their behavior in normal and extreme environmental conditions of the area in which construction is being carried out. The purpose of this work is to introduce the buildings that are most interesting in their architectural design and talk about the materials used in their construction. No. 1. 2. 3. 4. 5. 6. Project section Assumption Cathedral St. Isaac's Cathedral Intercession Cathedral Smolensk Assumption Cathedral St. Vladimir Church Presentation Objects used Photo Photo Photo Photo Photo Vladimir Assumption Cathedral It is located in Vladimir. The “Golden Age” of the construction of ancient Vladimir is the second half of the 12th century. The Assumption Cathedral of the city is the earliest architectural monument of this period. Built in 1158-1160 under Prince Andrei Bogolyubsky, the cathedral later underwent significant reconstruction. During the fire of 1185, the old Assumption Cathedral was severely damaged. Prince Vsevolod III, “who did not look for craftsmen from the Germans,” immediately began to restore it using local craftsmen. The building was made of hewn white stone, which formed a powerful “box” of the wall, which was filled with rubble and durable lime mortar. For information, rubble stone is large pieces of irregular shape measuring 150-500 mm, weighing 20-40 kg, obtained during the development of limestones, dolomites and sandstones (less commonly), granites and other igneous rocks. The stone obtained during blasting operations is generally called “ragged”. The rubble stone must be homogeneous, have no signs of weathering, delamination or cracks, and not contain loose and clayey inclusions. The compressive strength of stone from sedimentary rocks is not less than 10 MPa (100 kgf/cm), the softening coefficient is not less than 0.75, frost resistance is not less than 15 cycles. Rubble stone is widely used for rubble and rubble concrete masonry of foundations, walls of unheated buildings, retaining walls, ice cutters and tanks. The new Assumption Cathedral was created in the era of Vsevolod, about whom the author of “The Tale of Igor’s Campaign” wrote that the prince’s warriors could “splash the Volga with their oars.” The cathedral from one-domed becomes five-domed. There is relatively little sculptural decoration on its facades. Its plastic richness lies in the profiled slopes of slit-like windows and wide perspective portals with an ornamented top. Both its exterior and interior take on a new character. The interior decoration of the cathedral amazed contemporaries with its festive folk quality, which was created by the abundance of gilding, majolica floors, precious utensils and especially fresco murals. St. Isaac's Cathedral One of the no less beautiful buildings is St. Isaac's Cathedral, located in St. Petersburg. In 1707, the church, called St. Isaac's, was consecrated. On February 19, 1712, the public wedding ceremony of Peter I and Ekaterina Alekseevna took place there. On August 6, 1717, the second St. Isaac's Church was founded on the banks of the Neva, built according to the design of the architect G.I. Mattarnovi. Construction work continued until 1727, but already in 1722 the church was mentioned among the existing ones. However, the place for its construction was chosen poorly: the banks of the Neva had not yet been strengthened, and the beginning of soil sliding caused cracks in the walls and arches of the buildings. In May 1735, a fire broke out from a lightning strike, completing the destruction that had begun. On July 15, 1761, by decree of the Senate, the design and construction of the new St. Isaac's Church was entrusted to S.I. Chevakinsky, the author of St. Nicholas Cathedral. But he did not have to carry out his plan. Construction dates have been postponed. Having ascended the throne in 1762, Catherine II entrusted the design and construction to the architect Antonio Rinaldi. The cathedral was conceived with five intricately designed domes and a high bell tower. Marble cladding should add sophistication to the color scheme of the facades. This rock got its name from the Greek “mramoros” - brilliant. This carbonate rock is composed primarily of calcite and dolomite, and sometimes includes other minerals. It arises in the process of deep transformation of ordinary, that is, sedimentary limestones and dolomites. During metamorphic processes occurring under conditions of high temperature and high pressure, sedimentary limestones and dolomites recrystallize and become compacted; Many new minerals are often formed in them. For example, quartz, chalcedony, graphites, hematite, pyrite, iron hydroxides, chlorite, brucite, tremolite, garnet. Most of the listed minerals are observed in marble only in the form of single grains, but sometimes some of them are contained in significant quantities, determining important physical, mechanical, technical and other properties of the rock. Marble has a well-defined grain: on the surface of the chipped stone, reflections are visible that appear when light is reflected from the so-called cleavage planes of calcite and dolomite crystals. The grains are small (less than 1 mm), medium and large (several millimeters). The transparency of the stone depends on the size of the grains. Thus, Carrara white marble has a compressive strength of 70 megapascals and it collapses faster under load. The tensile strength of fine-grained marble reaches 150-200 megapascals and this marble is more resistant. But construction was extremely slow. Rinaldi was forced to leave St. Petersburg without completing the work. After the death of Catherine II, Paul I commissioned the court architect Vincenzo Brenna to hastily complete it. Brenna was forced to distort Rinaldi’s project: reduce the size of the upper part of the cathedral, build one instead of five domes; The marble cladding was extended only to the cornice; the upper part remained brick. The raw materials for sand-lime brick are lime and quartz sand. When preparing the mass, lime makes up 5.56.5% by weight, and water 6-8%. The prepared mass is pressed and then heated. The chemical essence of the hardening process of sand-lime brick is completely different than with a binder based on lime and sand. At high temperatures, the acid-base interaction of calcium hydroxide Ca(OH)2 with silicon dioxide SiO2 is significantly accelerated with the formation of calcium silicate salt CaSiO3. The formation of the latter ensures the bond between the sand grains, and, consequently, the strength and durability of the product. As a result, a squat brick building was created that was not in harmony with the ceremonial appearance of the capital. On April 9, 1816, during an Easter service, damp plaster fell from the vaults onto the right choir. Soon the cathedral was closed. In 1809, a competition was announced to create a project for the reconstruction of St. Isaac's Cathedral. Nothing came of the competition. In 1816, Alexander I instructed A. Betancourt to prepare regulations for the reconstruction of the cathedral and select an architect for this. Betancourt suggested entrusting this work to a young architect who came from France, Auguste Ricard de Montferrand. A. Betancourt presented the album with his drawings to the king. Alexander I liked the work so much that he issued a decree appointing Montferrand “imperial architect.” Only on July 26, 1819, the solemn act of renovation of St. Isaac's Church took place. The first granite stone with a gilded bronze plaque was placed on the piles. Granites are among the most common construction, decorative and facing materials and have played this role since ancient times. It is durable, relatively easy to process into different shapes, holds polish well and weathers very slowly. Typically, granite has a granular, uniform structure and, although it consists of multi-colored grains of different minerals, its overall color tone is uniform pink or gray. A geologist called granite a crystalline rock of deep igneous or mountain origin consisting of three main minerals: feldspar (usually about 30-50% of the rock volume), quartz (about 30-40%) and mica (up to 10-15%) . This is either pink microcline or orthoclase, or white albite or onigoclase, or two feldspars at once. Similarly, micas are either muscovite (light mica) or biotite (black mica). Sometimes other minerals are present in granite instead. For example, red garnet or greenhorn blende. All the minerals that make up granite are chemically silicates, sometimes with a very complex structure. On April 3, 1825, the Montferrand processing project was established. When constructing walls and support pylons, lime mortar was carefully prepared. Sifted lime and sand were alternately poured into the tubs so that one layer lay on top of the other, then they were mixed, and this composition was kept for at least three days, after which it was used for brickwork. Interestingly, lime is the oldest binding material. Archaeological excavations have shown that in the palaces of ancient China there were wall paintings with pigments fixed with slaked lime. Quicklime - calcium oxide CaO - was produced by roasting various natural calcium carbonates. CaCO₃ CaO +CO₂ The content of small amounts of undecomposed calcium carbonate in quicklime improves the binding properties. Lime slaking comes down to converting calcium oxide into hydroxide. CaO + H₂O Ca (OH)2 + 65 kJ Hardening of lime is associated with physical and chemical processes. Firstly, mechanically mixed water evaporates. Secondly, calcium hydroxide crystallizes, forming a calcareous framework of intergrown Ca(OH)₂ crystals. In addition, Ca(OH)₂ interacts with CO₂ to form calcium carbonate (carbonation). Poorly or “falsely” dried plaster can lead to peeling of the oil paint film due to the formation of soap as a result of the interaction of calcium alkali with drying oil fats. The addition of sand to lime paste is necessary because otherwise, when hardened, it shrinks severely and cracks. The sand serves as a kind of reinforcement. Brick walls were built from two and a half to five meters thick. Together with marble cladding, this is 4 times the usual wall thickness of civil buildings. External marble cladding, 5-6 cm thick, and internal, 1.5 cm thick, were made together with the brickwork of the walls and connected to it with iron hooks. The ceilings were made of brick. The sidewalk was supposed to be made of Serdobol granite, and the space behind the fence was to be paved with red marble platforms and a red granite border. White, gray, black and colored marbles are found in nature. Colored marbles are very widespread. There is no other decorative stone, with the exception, perhaps, of jasper, which would be characterized by very diverse colors and patterns, like colored marble. The color of marble is usually caused by a finely crystalline, often dusty, admixture of brightly colored minerals. Red, violet, purple colors are usually attributed to the presence of red iron oxide, the mineral sematite. Intercession Cathedral Intercession Cathedral (1555-1561) (Moscow) Built in the 16th century. by the brilliant Russian architects Barma and Postnik, the Intercession Cathedral - the pearl of Russian national architecture - logically completes the ensemble of Red Square. The cathedral is a picturesque structure of nine high towers, decorated with fancy domes of various shapes and colors. Another small figured (tenth) dome crowns St. Basil's Church. In the center of this group rises the main tower, sharply different in size, shape and decoration - the Church of the Intercession. It consists of three parts: a tetrahedron with a square base, an octagonal tier and a tent ending in an octagonal light drum with a gilded head. The transition from the octagonal part of the central part of the tower to the tent is carried out using a whole system of kokoshniks. The base of the tent rests on a wide white stone cornice shaped like an eight-pointed star. The central tower is surrounded by four large towers, located along the cardinal points, and four small ones, located diagonally. The lower tier rests with its edges on a complex-shaped and beautifully designed plinth made of red brick and white stone. Red clay brick is made from clay mixed with water, then molded, dried and fired. Formed brick (raw) should not crack when drying. The red color of the brick is due to the presence of Fe₂O₃ in the clay. This color is obtained if firing is carried out in an oxidizing atmosphere, that is, with an excess of oxygen. In the presence of reducing agents, grayish-lilac tones appear on the brick. Currently, hollow bricks are used, that is, they have cavities inside of a certain shape. For cladding buildings, two-layer bricks are made. When molding it, a layer of light-burning clay is applied to an ordinary brick. Drying and firing of two-layer facing bricks is carried out using conventional technology. Important characteristics of brick are moisture absorption and frost resistance. To prevent damage from weathering, brickwork is usually protected with plaster and tiling. A special type of fired clay brick is clinker. It is used in architecture for cladding the plinths of buildings. Clinker bricks are made from special clay with high viscosity and low deformability during firing. It is characterized by relatively low water absorption, high compressive strength and high wear resistance. Smolensk Assumption Cathedral From whichever direction you approach Smolensk, you can see the domes of the Assumption Cathedral - one of the largest churches in Russia - from afar. The temple crowns a high mountain located between two ravines deeply cut into the coastal slope. Crowned with five chapters (instead of seven according to the original version), festive and solemn, with lush Baroque decor on the facades, it rises high above the urban development. The grandeur of the building is felt both outside, when you stand at its foot, and inside, where, among the space filled with light and air, a gigantic, unusually solemn and magnificent gilded iconostasis rises upward, shimmering with gold - a miracle of wood carving, one of the outstanding works of decorative art of the 18th century , created in 1730-1739 by the Ukrainian master Sila Mikhailovich Trusitsky and his students P. Durnitsky, F. Olitsky, A. Mastitsky and S. Yakovlev. Next to the Assumption Cathedral, almost close to it, there is a two-tier cathedral bell tower. Small, it is somewhat lost against the background of the huge temple. The bell tower was built in 1767 in St. Petersburg Baroque forms according to the design of the architect Pyotr Obukhov, a student of the famous Baroque master D.V. Ukhtomsky. In the lower part of the bell tower, fragments of the previous building from 1667 are preserved. The Assumption Cathedral in Smolensk was built in 1677-1740. The first cathedral on this site was founded back in 1101 by Vladimir Monomakh himself. The cathedral became the first stone building in Smolensk, it was rebuilt more than once - including the Assumption Cathedral in Smolensk by the grandson of Monomakh, Prince Rostislav, until in 1611 the surviving defenders of Smolensk, who defended themselves for 20 months from the troops of the Polish king Sigismund III, finally, when the Poles They burst into the city and blew up the powder magazine. Unfortunately, the cellar was located right on Cathedral Hill, and the explosion practically destroyed the ancient temple, burying many Smolensk residents and the ancient tombs of Smolensk princes and saints under its rubble. In 1654, Smolensk was returned to Russia, and the pious Tsar Alexei Mikhailovich allocated as much as 2 thousand silver rubles from the treasury for the construction of a new main temple in Smolensk. The remains of the ancient walls, under the leadership of the Moscow architect Alexei Korolkov, were dismantled for more than a year, and in 1677 the construction of a new cathedral began. However, due to the fact that the architect violated the given proportions, construction was suspended until 1712. Assumption Cathedral in Smolensk. In 1740, under the leadership of architect A.I. Shedel, the work was completed and the temple was consecrated. In its original form, it stood for only twenty years, due to the presence of different architects and constant changes in the project. It ended with the collapse of the central and western chapters of the cathedral (there were seven in total at that time). The top was restored in 1767-1772, but with a simple traditional five-domed structure, which we now see. This cathedral is not only visible from everywhere, it is also truly huge - twice the size of the Assumption Cathedral in the Moscow Kremlin: 70 meters high, 56.2 meters long and 40.5 meters wide. The decoration of the cathedral is made in the Baroque style both outside and inside. The interior of the cathedral amazes with its pomp and luxury. Work on painting the temple lasted 10 years under the leadership of S.M. Trusitsky. Assumption Cathedral in Smolensk. The magnificent iconostasis, 28 meters high, has survived to this day, but the main shrine - the icon of the Mother of God Hodegetria - disappeared in 1941. Assumption Cathedral in Smolensk The cathedral bell tower, fading against the background of the huge temple, was built in 1763-1772. from the northwest of the cathedral. It was erected on the site of the previous bell tower, and the ancient foundations have been preserved at the base. At the same time, the cathedral fence was built with three high gates, shaped like triumphal arches. From the central street, a wide granite staircase of the same time leads up to Cathedral Hill, ending in a walkway. The cathedral was spared both by time and the wars that passed through Smolensk. After taking the city, Napoleon even ordered a guard to be posted, marveling at the splendor and beauty of the cathedral. The cathedral is now operational and services are held there. St. Vladimir's Church in Safonovo, Smolensk Region In May 2006, the city of Safonovo celebrated a significant anniversary - a hundred years ago the first church parish was opened on the territory of the future city. At that time, on the site of the current city blocks there were a number of villages, villages and farmsteads surrounding the railway station, which was called “Dorogobuzh” after the nearby county town. The closest village to the station was the village of Dvoryanskoye (current Krasnogvardeyskaya Street) and across the Velichka River from it was the landowner Tolstoy estate (now in its place is a small park). Tolstoy, which received its name from the Tolstoy nobles, has been known since the beginning of the 17th century. By the beginning of the 20th century it was a small owner's estate with one yard. Its owner was an outstanding public figure of the Smolensk province, Alexander Mikhailovich Tukhachevsky, a relative of the famous Soviet marshal. Alexander Tukhachevsky in 1902-1908 headed Dorogobuzh local government - zemstvo assembly, and in 1909-1917. led the provincial zemstvo council. The noble families owned the Leslie and Begichev families. The construction of a railway station on the banks of the Velichka River in 1870 turned this remote place into one of the most important economic centers of Dorogobuzh district. Timber warehouses, inns, shops, a postal station, a pharmacy, bakeries appeared here... The population of the station village began to grow. A fire brigade appeared here, and with it in 1906 a public library was organized - the first cultural institution of the future city. It is probably no coincidence that in the same year the spiritual life of the area received organizational form. In 1904, a stone temple was erected next to Tolstoy in the name of Archangel Michael, thereby turning the owner's estate into a village. Probably, the Archangel Church was for some time assigned to one of the nearby villages. However, already on May 4 (May 17 - according to the current style) 1906, a decree of the Holy Government Synod No. 5650 was issued, which stated: “At the newly built church in the village of Tolstoy, Dorogobuzh district, open an independent parish with a clergy of a priest and a psalm-reader in order to maintain The clergy of the newly opened parish relied exclusively on exquisite local funds.” Thus began the life of the parish of the village of Tolstoy and the Dorogobuzh station. Nowadays, the heir to the church in the village of Tolstoy is the St. Vladimir Church located in its place. Fortunately, history has preserved for us the name of the builder of the Archangel Michael Church. He was one of the most famous Russian architects and engineers, Professor Vasily Gerasimovich Zalessky. He was a nobleman, but initially his family belonged to the clergy and was known in the Smolensk region since the 18th century. People from this family entered the civil and military service and, having reached high ranks and ranks, claimed noble dignity. Since 1876, Vasily Gerasimovich Zalessky served as a city architect at the Moscow City Government and erected most of his buildings in Moscow. He built factory buildings, public houses, and private mansions. Probably the most famous of his buildings is the house of sugar refiner P.I. Kharitonenko on Sofiyskaya Embankment, where the residence of the English ambassador is now located. The interiors of this building were decorated by Fyodor Shekhtel in an eclectic style. Vasily Gerasimovich was a leading specialist in Russia in ventilation and heating. He had his own office, engaged in work in this area. Zalessky carried out extensive teaching activities and published a popular textbook on building architecture. He was a corresponding member of the St. Petersburg Society of Architects, a member of the Moscow Architectural Society, and headed the Moscow branch of the Society of Civil Engineers. At the end of the 19th century, V.G. Zalessky acquired a small estate of 127 acres in the Dorogobuzh district with the village of Shishkin. It was picturesquely located on the banks of the Vopets River. Now Shishkino is the northern outskirts of the city of Safonov. The estate was bought by Zalessky as a summer cottage. Despite the fact that Shishkino was a place of rest for Vasily Gerasimovich from his extensive professional activities, he did not remain aloof from the life of the local area. At the request of the chairman of the Dorogobuzh district assembly, Prince V.M. Urusov, Zalessky drew up plans and estimates for free for the construction of zemstvo primary schools with one and two classrooms. Two miles from Shishkin in the village of Aleshina, the Dorogobuzh zemstvo began to create a large hospital. In 1909, Vasily Zalessky accepted the obligation to be a trustee of this hospital under construction, and in 1911 he offered to equip it with central heating at his own expense. At the same time, the zemstvo asked him “to take part in supervising the construction of the hospital in Aleshin.” V.G. Zalessky was an honorary trustee of the fire brigade of the Dorogobuzh station and a donor of books for its public library. It is curious that in addition to the Archangel Michael Church in the village of Tolstoy, V.G. Zalessky is also related to the Smolensk Assumption Cathedral. According to his relatives, he installed central heating there. Soon after the opening of the parish, a parochial school appeared in the village of Tolstoy, which had its own building. The first mention of it dates back to 1909. The current St. Vladimir Church of Safonov is famous for its beautiful church choir. A remarkable fact is that a century ago the same glorious choir was in the church in the village of Tolstoy. In 1909, in an article in the Smolensk Diocesan Gazette, dedicated to the consecration of the newly built large nine-domed church in the village of Neyolova, it was reported that during the solemn service, the singing choir from the Dorogobuzh station sang beautifully. The Archangel Michael Church, like any newly built church, did not have ancient icons and was probably quite modest in its interior decoration. In any case, the rector of the temple noted in 1924 that only two icons - the Mother of God and the Savior - have any artistic value. Currently, the name of only one rector of the temple is known. From December 1, 1915 and at least until 1924, he was Father Nikolai Morozov. He probably served in the Tolstoy church in subsequent years. In 1934, the church in the village of Tolstoy was closed by decree of the Smolensk Regional Executive Committee No. 2339 and was used as a warehouse for high-quality grain. During the Great Patriotic War, the church building was destroyed and only in 1991, according to the only surviving photograph, the destroyed church was rebuilt through the efforts of its abbot, Father Anthony Mezentsev, who now heads the community of the Boldinsky Monastery with the rank of archimandrite. Thus, the first temple of Safonov completed the circle of its life, in some ways repeating the path of the Savior: from crucifixion and death for faith to the resurrection by Divine providence. Let this miracle of the revival from the ashes of the destroyed Safonov shrine become for the residents of the city a vivid example of the creative power of the human spirit and the faith of Christ.

The variety of methods for studying the composition and technology of ancient materials is becoming difficult to comprehend. Let's briefly look at the methods that are most widely known and tested.

The choice of one or another method for studying the composition of ancient objects is dictated by historical and archaeological problems. In general, such problems are few, but they can be solved by different means.

Metal in the form of alloys, ceramics and fabrics are the first artificial materials consciously created by man. Such materials do not exist in nature. The creation of metal alloys, ceramics and textiles marked a qualitatively new stage in technology: a transition from the appropriation and adaptation of natural materials to the production of artificial materials with predetermined properties.

When studying the composition of ancient materials, the following questions are usually considered. Was the item made locally or far from where it was found? If far away, is it possible to indicate the place where it was made? Is the composition of a material, such as an alloy of some metals, intentional or accidental? What was the technology of this or that production process? What was the level of labor productivity when using this or that technique for processing stone, bone, wood, metal, ceramics, glass, etc.? For what purpose were certain tools used? These and other similar questions can be answered based mainly on two types of research: analysis of matter and physical modeling of ancient technological processes.

SUBSTANCE ANALYSIS

The most accurate of the traditional methods of analyzing a substance is chemical analysis. The substance under study is processed in various solutions, in which certain constituent elements precipitate. The precipitate is then calcined and weighed. For such an analysis, a sample of at least 2 g is needed. It is clear that such a sample cannot be separated from every object without destroying it. Chemical analysis is very labor-intensive, and an archaeologist needs to know the composition of hundreds and thousands of objects. In addition, a number of elements present in this subject in
in tiny quantities, practically undetectable chemically.

Optical spectral analysis. If a small amount of a substance of 15-20 mg is burned in the flame of a voltaic arc and passing the light of this arc through a prism, then projecting it onto a photographic plate, then a spectrum will be recorded on the developed plate. In this spectrum, each chemical element has its strictly defined place. The greater its concentration in a given object, the more intense the spectral line of this element will be. The intensity of the line determines the concentration of the element in the burned sample. Spectral analysis makes it possible to detect very small impurities, on the order of 0.01%, which is very important for some questions faced by an archaeologist. Of course, only the most general principle of spectral analysis is outlined here. Its practical implementation is carried out using special equipment and requires certain skills. Instruments for spectral analysis are produced commercially. The analysis technique is not so complicated, and if desired, the archaeologist can master it in a fairly short time. At the same time, a very unproductive intermediate link is excluded, when an archaeologist who is not versed in the technique of analysis must explain his tasks to a surveyor who is poorly versed in archaeological issues. Therefore, the ideal situation seems to be when a professional spectral specialist working in a scientific team of archaeologists becomes so familiar with archaeological problems that he himself can formulate tasks for studying the composition of ancient materials.

Spectral analysis of archaeological finds allowed us to obtain many interesting results.

Ancient bronze. The most important studies using spectral analysis relate to the origin and distribution of ancient copper and bronze metallurgy. They made it possible to move from approximate visual assessments (copper, bronze) to precise quantitative characteristics of the alloy components and to the identification of various types of copper-based alloys.

Until relatively recently, it was believed that the metallurgy of copper and bronze originates from Mesopotamia, Egypt and Southern Iran, where it was known since the 4th millennium BC. e. The mass production of analyzes of bronze objects made it possible to raise the question not about regions, but about specific ancient mine workings, to which certain types of alloys can be “linked” with a certain probability. Ore from each deposit has a specific set of microimpurities inherent only to this deposit. When smelting ore, the composition and amount of these impurities may vary somewhat, but can be taken into account. Thus, it is possible to obtain certain “marks” that characterize the characteristics of the metals of a particular deposit or group of deposits, or mining centers. The characteristics of such mining centers as the Balkan-Carpathian, Caucasian, Ural, Kazakhstan, and Central Asian are well known.

Currently, the oldest traces of copper smelting and processing and lead products have been discovered in Asia Minor (Catal Huyuk, Hacilar, Cheyunyu Tepesi, etc.). They date back at least a thousand years earlier than similar finds from Mesopotamia and Egypt.

An analysis of materials obtained during excavations at the oldest copper mine in Europe, Ai-Bunar (on the territory of modern Bulgaria), showed that already in the 4th millennium BC. Europe had its own source of copper. Bronze products were made from ores mined in the Carpathians, the Balkans and the Alps.

Based on a statistical analysis of the composition of ancient bronze objects, it was possible to establish the main directions of the evolution of bronze technology itself. Tin bronze did not appear in most mining and metallurgical centers immediately. It was preceded by arsenic bronze. Alloys of copper and arsenic could be natural. Arsenic is present in a number of copper ores and, when smelted, partially transforms into the metal. It was believed that arsenic impurities deteriorate the quality of bronze. Thanks to mass spectral analysis of bronze objects, it was possible to establish an interesting pattern. Items intended for use under conditions of strong mechanical loads (spear tips, arrows, knives, sickles, etc.) had an admixture of arsenic in the range of 3-8%. Items that should not have experienced any mechanical stress during use (buttons, plaques and other decorations) had an admixture of arsenic of 8-15%. In certain concentrations (up to 8%), arsenic plays the role of an alloying additive: it gives bronze high strength, although the appearance of such a metal is inconspicuous. If the concentration of arsenic is increased above 8-10%, bronze loses its strength qualities, but acquires a beautiful silvery tint. In addition, at a high concentration of arsenic, the metal becomes more fusible and fills all the recesses of the casting mold well, which cannot be said about viscous, quickly cooling copper. The fluidity of the metal is important when casting jewelry with complex shapes. Thus, indisputable evidence was obtained that the ancient craftsmen knew the properties of bronze and were able to produce metal with predetermined properties (Fig. 39). Of course, this happened under conditions that had nothing in common with our ideas about metallurgical production with its precise recipes, express analyzes, etc. For all ancient peoples, blacksmithing was surrounded by an aura of magic and mystery. When throwing bright red realgar stones or golden-orange pieces of orpiment containing significant concentrations of arsenic into the smelting furnace, the ancient metallurgist most likely recognized this as some kind of magical effect with the “magic” stones having the revered red color. Generations of experience and intuition told the ancient master what additives and in what quantities were needed when making things intended for various purposes.

In a number of areas where there were no reserves of arsenic or tin, bronze was obtained in the form of an alloy of copper and antimony. Thanks to spectral analysis, it was possible to establish that Central Asian craftsmen, even at the turn of our era, were able to produce an alloy that was very close in composition and properties to modern brass. Thus, among the items found during excavations of the Tulkha burial ground (2nd century BC - 1st century AD, Southern Tajikistan), there were many earrings, buckles, bracelets and other brass items.

Spectral analysis of a large number of bronze items from Scythian monuments in Eastern Europe indicated that the composition of the alloys of Scythian bronze does not trace continuity from previous cultures of the Late Bronze Age of this region. At the same time, there are things here whose alloy composition is similar in concentration to alloys from the eastern regions (Southern Siberia and Central Asia). This serves as an additional argument in favor of the hypothesis about the eastern origin of the Scythian-type culture.

Using spectral analysis, it is possible to study the nature of the distribution in time and space of not only bronze, but also other materials. In particular, there is successful experience in studying the distribution of flint in the Neolithic era, as well as glass and ceramics in various historical periods.

In recent years, in the practice of archaeological research, the role of modern and, for archaeology, new research methods has been increasing.

Stable isotopes. Just as the microimpurities mentioned above in ancient metals, flint, ceramics and other materials are natural marks, a kind of “passports”, in some cases the ratio of stable, i.e. non-radioactive, isotopes in some substances plays approximately the same role.

On the territory of Attica and on the islands of the Aegean Sea, silver items are found during excavations of monuments of the Chalcolithic and Early Bronze Age (IV-III millennium BC). During Schliemann's excavations of Mycenaean shaft tombs (16th century BC), silver objects were clearly of Egyptian origin. These and other observations, in particular the famous ancient silver mines in Spain and Asia Minor, became the basis for the conclusion that the ancient inhabitants of Attica did not mine their silver, but imported it from these centers. This opinion was generally accepted in Western European archeology until very recently.

In the mid-70s, a group of English and German physicists and archaeologists began a series of studies of ancient mines in Lavrion (near Athens) and on the islands of Sifnos, Naxos, Siroe, etc. The physical basis of the study was as follows. Due to imperfect cleaning methods, ancient silver items contain lead impurities. Lead has four stable isotopes with atomic weights 204, 206, 207 and 208. Once smelted from its ore, the isotopic composition of the lead originating from a given deposit remains constant and does not change from hot and cold working, corrosion or alloying with other metals. The ratio of isotopes in a given sample is recorded with great accuracy by a special device - a mass spectrometer. By determining the isotopic composition of samples of various ores originating from specific mines, and then comparing their isotopic composition with samples of silver items, the source of the metal for each item can be pinpointed.

Ancient mines were exploited for centuries and millennia, and in this case it was important to know which of the more than 30 ancient deposits surveyed had silver-lead minerals mined in the Bronze Age. Using C14 and thermoluminescence of ceramics, it was possible to date individual workings dating back to the end of the 4th-3rd millennium BC. e. Then ore samples from these workings were subjected to mass spectroscopic examination for lead. Lead isotope ratios in samples from different ancient workings were distributed over non-overlapping areas, indicating “tags” inherent in each deposit (Fig. 50). The isotope ratios in the silver objects themselves were then analyzed. The results were unexpected. All items were made from local silver, originating either from Lavrio or from the island mines, mainly from the island of Sifnos. As for the Egyptian silver objects found in Mycenae, they were made from silver mined in Laurion, exported to Egypt. Items made in Egypt from Athenian silver were brought to Mycenae.

A similar problem was considered to identify marble objects with marble sources. This question is important from different angles. Works of Greek sculpture or architectural details made of marble are found at great distances from mainland Greece. Sometimes it is very important to answer the question of what marble, local or imported from Greece, is a sculpture, or the capital of a column, or any other object made of. Modern counterfeits of antiquity find their way into museum collections. They need to be identified. Restorers, etc. need to know the sources of marble for a particular structure.

The physical basis is the same: stable isotope mass spectrometry, but instead of lead, the ratio of the isotopes of carbon, 2C and 13C, and oxygen, 80 and 160, is measured.
The main deposits of marble in Ancient Greece were on the mainland (mountains Pentelikon and Hymettus near Athens) and on the islands of Naxos and Paros. It is known that the Parian marble quarries, or rather mines, are the most ancient. Measurements of marble samples from quarries and measurements of samples from ancient sculptures (non-destructive analysis: a sample of tens of milligrams is required) and architectural details made it possible to connect them with each other (Fig. 51).

Similar results can be obtained by conventional, petrographic or chemical analysis. For example, it was found that samples of Gandhara sculpture stored in museums in Taxila, Lahore, Karachi, and London were made of stone taken from a quarry in the Swat Valley in Pakistan, in the Mardai district near the Takht-i-Bahi monastery. However, analysis using a mass spectrometer is more accurate and less labor intensive.

Neutron activation analysis (NAA). Neutron activation analysis is perhaps the most powerful and effective means of determining the chemical composition of an object from a long series of elements at once. In addition, this is a non-destructive analysis. Its physical essence is

Rice. 51. Comparison of marble samples from architectural details and sculptures with samples from quarries:
1 - Naxos island; 2 - Paros island; 3 - Mount Pentelikon; 4 - Mount Gimmettus; 5 - samples from monuments

that when any substance is irradiated with neutrons, the reaction of radiative capture of neutrons by the nuclei of the substance occurs. As a result, the excited nuclei emit their own radiation, and each chemical element has its own energy and has its own specific place in the energy spectrum. In addition, the greater the concentration of a given element in a substance, the more energy is emitted in the spectral region of that element. Externally, the situation is similar to what we observed when considering the basics of optical spectral analysis: each element has its own place in the spectrum, and the degree of blackening of the photographic plate in a given place depends on the concentration of the element. Unlike others, neutron activation analysis has very high sensitivity: it detects millionths of a percent.

In 1967, the University of Michigan Museum of Art (USA) organized an exhibition of Sasanian silver, which included objects from various museums and private collections. These were mainly silver dishes with embossed images of various scenes: Sasanian kings hunting, at feasts, epic heroes, etc.). Experts suspected that among the genuine masterpieces of Sasanian toreutics there were modern fakes. Neutron activation analysis showed that more than half of the exhibits were made from modern silver of a purified composition that was unattainable in ancient times. But this is, so to speak, a crude fake, and such a fake is now very easy to detect by its chemical composition. But among the objects of this exhibition there were dishes that, although they differed from the genuine ones in their chemical composition, were not so much that on this basis alone they could be considered fakes. Experts believe that in this case a more sophisticated forgery cannot be ruled out. Scrap of ancient silver could have been used to make the dish itself. Moreover, even individual applied embossed parts could be genuine, while the rest of the composition could be skillfully forged. This is indicated by some stylistic and iconographic subtleties, visible only to the experienced eye of a professional art historian or archaeologist. From this example, an important conclusion for an archaeologist follows: any, the most advanced physical and chemical analysis must be combined with cultural, historical and archaeological research.

The neutron activation method is used to solve archaeological problems of various levels. For example, a deposit has been identified in which huge monoliths of ferruginous quartzite were mined to make giant statues (15 m high) of the temple complex of Amenhotep III in Thebes (15th century BC). Several deposits were suspected, located at different distances from the complex: approximately from 100 to 600 km. Based on the concentration of some elements, especially the extremely low europium content (1-10%), it was possible to establish that the monoliths for the statues were delivered from the most remote quarry, where quartzite was mined with a fairly homogeneous structure suitable for processing.

For all its temptingness, the neutron activation method cannot yet be considered generally accessible to an archaeologist, the same as, for example, spectral analysis or metallography. In order to obtain the energy spectrum of a substance, it needs to be irradiated in a nuclear reactor, and this is not very accessible and also expensive. When it comes to verifying the authenticity of a masterpiece, this is a one-step study, and in this case, as a rule, the costs of examination are not taken into account. But if, to solve ordinary current scientific problems, an archaeologist needs to analyze hundreds or thousands of samples of ancient bronze, ceramics, silicon and other materials, the neutron activation method turns out to be too expensive.

STRUCTURE ANALYSIS

Metallography. An archaeologist often has questions about the quality of metal products, their mechanical properties, methods of their manufacture and processing (casting in an open or closed mold, with fast or slow cooling, hot or cold forging, welding, carburizing, etc.). Metallographic research methods provide answers to these questions. They are very diverse and not always easily accessible. At the same time, quite satisfactory results in various areas of archeology were obtained using a relatively simple method.
microscopic examination of thin sections. After some training, this method can be mastered by the archaeologist himself. Its essence is that various methods of processing iron, bronze and other metals leave their “traces” in the structure of the metal. A polished section of a metal product is placed under a microscope and the technique of its manufacture or processing is determined by the distinguishable “traces”.

Important results were obtained in the field of metallurgy and processing of iron and steel. During the Hallstatt period, basic skills in the plastic processing of iron appeared in Europe, with rare attempts to make steel blades by carburizing iron and hardening it. The imitation of bronze objects in shape is clearly visible, just as in their time bronze axes inherited the shape of stone ones. A metallographic study of iron products of the subsequent La Tène era showed that at that time the technology of steel production had already been fully mastered, including rather complex methods for producing welded blades with a high quality cutting surface. Recipes for making steel products passed through all of Roman times practically without any special changes and had a certain influence on the level of blacksmithing in early medieval Europe.

The Scythian-Sarmatian cultures of Eastern Europe, synchronous with the late Hallstatt and La Tène, also possessed many secrets of steel production. This is shown by a series of works by Ukrainian archaeologists who widely used metallographic methods.
Metallographic analysis of copper products of the Trypillian culture made it possible to establish the sequence of improvement of copper processing technology over a long period of time. At first it was the forging of native copper or metallurgical, smelted from pure oxide minerals. Early Tripoli masters apparently did not know casting technology, but they achieved great success in forging and welding techniques. Casting with additional forging of working parts appears only in the Late Tripolie period. Meanwhile, the southwestern neighbors of the early Trypillians - the tribes of the Karanovo VI - Gumelnitsa culture already knew different techniques for casting in open and closed molds.

Of course, the most significant results are obtained by combining metallographic studies with other methods of analysis: spectral, chemical, X-ray diffraction, etc.

Petrographic analysis of stone and ceramics. Petrographic analysis is similar in its technique to metallographic analysis. The initial object of analysis in both cases is a polished section, that is, a polished section of an object or its sample placed under a microscope. The structure of this rock is clearly visible under a microscope. The nature, size, and number of different grains of certain minerals determine the characteristics of the material being studied, according to which it can be “tied” to a particular deposit. This is relative to the stone. Polished sections obtained from the ceramics make it possible to determine the mineralogical composition and microstructure of the clay, and parallel analysis of clay from supposed ancient quarries makes it possible to identify the product with its raw materials.

When turning to petrographic analysis, a clear formulation of the questions that the archaeologist wants to answer is necessary. Petrographic research is quite labor-intensive. It requires the production and study of a fairly large number of thin sections, which is not cheap. Therefore, such studies, like all others, are not done “just in case.” We need a clear formulation of the question that we want to answer using petrographic analysis.

For example, during a petrographic study of Neolithic tools found at sites and in graves in the lower reaches of the Tom River and in the Chulym basin, specific questions were posed: did the inhabitants of these microdistricts use raw materials from local sources or from distant ones? Was there an exchange of stone products between them? The analysis was carried out on more than 300 thin sections taken from various stone tools from stone deposits in the area. A study of thin sections showed that approximately two thirds of the total number of stone tools were made from local raw materials (silicified siltstones). Some abrasive tools are made from local sandstone and shale rocks. At the same time, individual adzes, bumpers and other objects were made from rocks that had deposits on the Yenisei and in the Kuznetsk Ala-Tau (serpentine, jasper-like silicite, etc.). Based on these facts, it could be concluded that the bulk of the tools were made from local raw materials, and the exchange was insignificant. The answer to these kinds of questions can be obtained by other methods, for example, spectral or neutron activation methods.

Unlike the inhabitants of the valleys of the Tom and Chulym rivers, the Neolithic tribes of Asia Minor actively exchanged tools or workpieces made from obsidian. This was established through spectral analysis of the tools themselves and samples of obsidian deposits, which clearly differed from each other in the concentration of elements such as barium and zirconium.

Analysis of the structure of ancient materials should also include the study of fabrics, leather, and wood products, which makes it possible to identify special technological techniques inherent in a given culture or period. For example, the study of fabrics found during excavations of Noin-Ula, Pazyryk, Arzhan, Moshchevaya Balka and other monuments made it possible to establish the paths of ancient economic and cultural ties with very remote regions.

EXPERIMENTAL MODELING OF ANCIENT TECHNOLOGIES

Analysis of substance and structure allows us to learn about the composition and technology of ancient materials and answer various questions of a cultural and historical nature. However, here too an integrated approach is needed, a combination with other methods. The greatest completeness of understanding of many production processes is achieved by means and methods of physical modeling of ancient technologies. This direction in archeology has now become widespread under the name “experimental archaeology”.

Along with archaeological expeditions that excavate ancient monuments, in recent years completely unusual archaeological expeditions have been created in universities and scientific institutions of the USSR, Poland, Austria, Denmark, England, the USA and other countries. Their main goal is to find out in practice, experimentally, certain problems of reconstructing the way of life and the level of technology of ancient groups. Students and graduate students, professors and researchers make stone axes, use them to cut poles and logs, build dwellings and cattle pens, exact replicas of dwellings and other structures studied during excavations. They live in such dwellings, using only those tools and means of labor that existed in ancient times, sculpting and firing pottery, melting metal, cultivating arable land, raising livestock, etc. All this is recorded in detail, analyzed and generalized. The results are interesting and sometimes unexpected. The work of S. A. Semenov and his students made it possible to put hypotheses about the level of labor productivity in primitive communities under strict experimental control. Labor productivity is one of the main measures of progress in all periods of history. Scientists' ideas about labor productivity in the Stone Age were very speculative. In old textbooks you can find a phrase that the Indians polished a stone ax for so long that sometimes a whole life was not enough to do it. S. A. Semenov showed that depending on the hardness of the stone, this operation took from 3 to 25 hours. It turned out that the productivity of the Trypillian sickle made of flint inserts is only slightly inferior to the modern iron sickle. Residents of the Trypillian village could harvest a grain crop per hectare with four people in about three daylight hours.

Experimental smelting of bronze and iron made it possible to understand in more detail a number of “secrets” of ancient craftsmen, to make sure that some technological techniques and skills of foundries and blacksmiths were not in vain covered with an aura of magic. Soviet, Czech and German archaeologists tried many times to obtain kritsa from sponge iron smelted in a cheese furnace, but there was no lasting result. Experimental smelting of copper-tin ore from ancient workings in the Fan Mountains (Tajikistan) showed that in some cases ancient foundries were engaged not so much in the selection of alloy components, but in the use of ores with natural associations of different metals. It is possible that Bactrian brasses are also the result of the use of a special ore with a natural composition of copper-tin-zinc-lead.

On this day:

Man has always sought to find materials that leave no chance for his competitors. Since ancient times, scientists have been looking for the hardest materials in the world, the lightest and the heaviest. The thirst for discovery led to the discovery of an ideal gas and an ideal black body. We present to you the most amazing substances in the world.

1. The blackest substance

The blackest substance in the world is called Vantablack and consists of a collection of carbon nanotubes (see carbon and its allotropes). Simply put, the material consists of countless “hairs”, once caught in them, the light bounces from one tube to another. In this way, about 99.965% of the light flux is absorbed and only a tiny fraction is reflected back out.
The discovery of Vantablack opens up broad prospects for the use of this material in astronomy, electronics and optics.

2. The most flammable substance

Chlorine trifluoride is the most flammable substance ever known to mankind. It is a strong oxidizing agent and reacts with almost all chemical elements. Chlorine trifluoride can burn concrete and easily ignite glass! The use of chlorine trifluoride is practically impossible due to its phenomenal flammability and the impossibility of ensuring safe use.

3. The most poisonous substance

The most powerful poison is botulinum toxin. We know it under the name Botox, which is what it is called in cosmetology, where it has found its main application. Botulinum toxin is a chemical produced by the bacteria Clostridium botulinum. In addition to the fact that botulinum toxin is the most toxic substance, it also has the largest molecular weight among proteins. The phenomenal toxicity of the substance is evidenced by the fact that only 0.00002 mg min/l of botulinum toxin is enough to make the affected area deadly to humans for half a day.

4. The hottest substance

This is the so-called quark-gluon plasma. The substance was created by colliding gold atoms at near light speed. Quark-gluon plasma has a temperature of 4 trillion degrees Celsius. For comparison, this figure is 250,000 times higher than the temperature of the Sun! Unfortunately, the lifetime of matter is limited to a trillionth of one trillionth of a second.

5. The most caustic acid

In this nomination, the champion is fluoride-antimony acid H. Fluoride-antimony acid is 2×10 16 (two hundred quintillion) times more caustic than sulfuric acid. It is a very active substance and can explode if a small amount of water is added. The fumes of this acid are deadly poisonous.

6. The most explosive substance

The most explosive substance is heptanitrocubane. It is very expensive and is used only for scientific research. But the slightly less explosive octogen is successfully used in military affairs and in geology when drilling wells.

7. The most radioactive substance

Polonium-210 is an isotope of polonium that does not exist in nature, but is manufactured by humans. Used to create miniature, but at the same time, very powerful energy sources. It has a very short half-life and is therefore capable of causing severe radiation sickness.

8. The heaviest substance

This is, of course, fullerite. Its hardness is almost 2 times higher than that of natural diamonds. You can read more about fullerite in our article The Hardest Materials in the World.

9. The strongest magnet

The strongest magnet in the world is made of iron and nitrogen. At present, details about this substance are not available to the general public, but it is already known that the new super-magnet is 18% more powerful than the strongest magnets currently in use - neodymium. Neodymium magnets are made from neodymium, iron and boron.

10. The most fluid substance

Superfluid Helium II has almost no viscosity at temperatures close to absolute zero. This property is due to its unique property of leaking and pouring out of a vessel made of any solid material. Helium II has prospects for use as an ideal thermal conductor in which heat does not dissipate.

Chemicals are widely used not only for conducting chemical experiments, but also for making various crafts, and also as building materials.

Chemicals as building materials

Let's consider a number of chemical elements that are used in construction and more. For example, clay is a fine-grained sedimentary rock. It consists of minerals of the kaolinite, montmorillonite or other layered aluminosilicates group. It contains sand and carbonate particles. Clay is a good waterproofing agent. This material is used to make bricks and as a raw material for pottery.

Marble is also a chemical material that consists of recrystallized calcite or dolomite. The color of marble depends on the impurities it contains and may have a striped or variegated tint. Iron oxide gives marble its red color. With the help of iron sulfide it acquires a blue-black hue. Other colors are also due to impurities of bitumen and graphite. In construction, marble refers to marble itself, marbled limestone, dense dolomite, carbonate breccias and carbonate conglomerates. It is widely used as a finishing material in construction, to create monuments and sculptures.

Chalk is also a white sedimentary rock that is insoluble in water and is of organic origin. It mainly consists of calcium carbonate and magnesium carbonate and metal oxides. Chalk is used in:

• medicine;
• sugar industry, for purification of glassy juice;
• production of matches;
• production of coated paper;
• for rubber vulcanization;
• for the production of compound feed;
• for whitewashing.

The scope of application of this chemical material is very diverse.

These and many other substances can be used for construction purposes.

Chemical properties of building materials

Since building materials are also substances, they have their own chemical properties.

The main ones include:

1. Chemical resistance - this property shows how resistant the material is to other substances: acids, alkalis, salts and gases. For example, marble and cement can be destroyed by acid, but they are resistant to alkali. Silicate building materials, on the contrary, are resistant to acids, but not to alkali.
2. Corrosion resistance is the ability of a material to withstand environmental influences. Most often this refers to the ability to keep moisture out. But there are also gases that can cause corrosion: nitrogen and chlorine. Biological factors can also cause corrosion: exposure to fungi, plants or insects.
3. Solubility is a property in which a material has the ability to dissolve in various liquids. This characteristic should be taken into account when selecting building materials and their interaction.
4. Adhesion is a property that characterizes the ability to connect with other materials and surfaces.
5. Crystallization is a characteristic in which a material can form crystals in a state of vapor, solution or melt.

The chemical properties of materials must be taken into account when carrying out construction work in order to prevent incompatibility or unwanted compatibility of some building substances.

Chemically cured composite materials

What are chemical curing composite materials and what are they used for?

These are materials that are a system of two components, for example, “powder-paste” or “paste-paste”. In this system, one of the components contains a chemical catalyst, usually benzene peroxide or another chemical polymerization activator. When the components are mixed, the polymerization reaction begins. These composite materials are often used in dentistry for the manufacture of fillings.

Nanodispersed materials in chemical technology

Nanodispersed substances are used in industrial production. They are used as an intermediate phase in the preparation of materials with a high degree of activity. Namely, in the production of cement, the creation of rubber from rubber, as well as for the production of plastics, paints and enamels.

When creating rubber from rubber, finely dispersed carbon black is added to it, which increases the strength of the product. In this case, the filler particles must be small enough to ensure the homogeneity of the material and have high surface energy.

Chemical technology of textile materials

Textile chemical technology describes the processes of preparing and processing textiles using chemicals. Knowledge of this technology is necessary for textile production. This technology is based on inorganic, organic, analytical and colloidal chemistry. Its essence lies in highlighting the technological features of the processes of preparation, coloring and final finishing of textile materials of various fibrous compositions.

You can learn about these and other chemical technologies, such as the chemical organization of genetic material, at the Chemistry exhibition. It will take place in Moscow, on the territory of the Expocentre.