KEY WORD:
periodic system of D.I. Mendeleev, periodic law, layers, periods, groups, rows, quantum numbers, a long period version, a short period version, Klitschkovsky rule

ABSTRACT:
The paper presents a long-period version of the hypothetical structure of the periodic system of chemical elements by D.I. Mendeleev with Z> 118. For comparison, a short form of an impersonal table is given, where instead of the names and characteristics of atoms, integers are arranged in ascending order. The analysis of the obtained images made it possible to discover the periodicity of the properties of integers and put forward a hypothesis that the periodicity of the properties of the natural series of numbers underlies the periodicity of the properties of chemical elements.
It is shown that each period includes two rows of elements. In this regard, a zero series is introduced in the first period, in which it is proposed to place an electron, proton, and neutron. In turn, each pair of periods forms a layer, which corresponds to the generalized principal quantum number m, and the number of elements is determined by the formula N = 2m². In the long-period variant, the rows are absent.

For citation: Sarkisov Yu. S. Generalization of long and short period versions of the table of chemical elements D.I. Mendeleeva with Z> 118// Technique and technology of silicates. – 2020.Vol. 27, No4. – Pp 98 – 103.

KEY WORD:
vermiculite, expanded vermiculite, pore structure, pore size, pore size distribution

ABSTRACT:
The results of investigations of the pore structure of two fractions of expanded vermiculite 8-4 mm and 2-0.7 mm, measured by the methods of gas adsorption and mercury porosimetry are presented. It was found that expanded vermiculite does not contain micro- (<2 nm) and mesopores (2-50 nm) according to the classification of M.M. Dubinin. Using the method of mercury porosimetry, it was determined that the pore sizes fit in the range of 50 nm to 100 microns (macropores), and the average pore size of expanded vermiculite increases with increasing fraction size: 8.54 microns for the 8-4 mm fraction and 3.56 microns for fractions 2-0.7 mm. Additionally, important properties such as porosity, apparent density and specific surface area have been determined. The results of measurements by each of the methods allow a more complete description of the pore structure of expanded vermiculite.

For citation: Yurkov A.L., Skurikhin V.V., Skurikhin A.V. Repeated structure of extended vermiculitis // Technique and technology of silicates. – 2020.Vol. 27, No4. – Pp 103 – 107.

KEY WORD:
fresh concrete, flowability, ultrahigh-performance concrete, UHPC, mix design.

ABSTRACT:
This paper represents the development of a methodology of designing an ultra high performance concrete with a given flowability. The flowability of fresh concrete was determined by measuring the spread of the mixture from a small cone in accordance with GOST 310.4. A model was obtained for calculating the flowability of concrete mixtures, which is based on two parameters: the thickness of the excess paste layer around the aggregate grains and the flowability of the cement paste. The average deviation of the calculated values from the actual ones is 2.7%. It was shown how, using the obtained model, the composition of a concrete mixture with predetermined properties is calculated. A relationship was built between the spreading of the mixture from a normal Abbrams cone in accordance with GOST 10181 and from a small cone in accordance with GOST 310.4. A relationship was obtained between the packing density of monosized sands and the coefficient taking into account the shape of the grains, which can be used for refined calculations of the specific surface area of the aggregate.

For citation: Soloviev V., Matiushin E. A methodology of ultrahigh-performance concrete mix design with a given flowability // Technique and technology of silicates. – 2020.Vol. 27, No4. – Pp 107 – 113.

KEY WORD:
Portland slag cement, ultrafine slag, slag suspension, plasticizer, acoustic cavitation, strength, porosity, aggregative stability factors

ABSTRACT:
This article reveals some methods to increase initial strength of slag Portland cement by modifying it with ultrafine component. Granulated blast-furnace slag, grinded in a laboratory vortex jet mill with upper limit of particle size of 1 μm was used as an ultrafine component. Then the ultrafine dry slag was mixed together with Portland slag cement; in the form of suspension instead of mixing water. Slag suspensions were prepared in water solution and in water-polymer dispersion media. To obtain stable suspensions polycarboxylate resins were used as a plasticizer. To stabilize these water and water-polymer suspensions acoustic cavitation was performed. Comparison of physical, mechanical and structural properties of the modified samples illustrates the most efficient way of introducing the slag suspension into the slag Portald cement as a mixing water stabilized by plasticizer and acoustic cavitation.

For citation: Samchenko S.V., Kozlova I.V., Zemskova O.V., Dudareva M.O., Shubina E.S. Comparative analysis of methods for modifying slag-Portland cement with ultra-disperse component // Technique and technology of silicates. – 2020.Vol. 27, No4. – Pp 113 – 120.

KEY WORD:
reaction-powder concrete, grinding, activation.

ABSTRACT:
The relevance of the issue related to resource conservation in the design of concrete mix is ​​gaining momentum every year. One of the ways to reduce resource costs is to activate both binders and concrete aggregates. In the 1990s, a new type of concrete based on Portland cement was developed - reaction-powder concrete. For the production of more than half of the initial components of reaction-powder concrete, grinding is used. Various equipment is used as grinding, one of which is a disintegrator. However, despite the interest of scientists in the activation of various raw materials, the question of obtaining an ultrafine material with the required properties remains unresolved.
The authors carried out a literary review, highlighting the relevance of the topic, the issues of grinding and activating the components of reaction-powder concrete, as well as research experiments and conclusions of various scientists involved in grinding the initial components of reaction-powder concrete. Preliminary experiments were performed to illustrate the possibility of using disintegrator technology in the design of reactive powder concrete.

For citation: Samchenko S.V., Abramov M.A., Osmanov A.B. Development prospects reactive-powder concrete // Technique and technology of silicates. – 2020.Vol. 27, No4. – Pp 120 – 123.

KEY WORD:
calcium sulfaaluminoferrite, ettringite, low-basic calcium hydrosilicates, corrosion resistance

ABSTRACT:
The phase composition of sulfaaluminoferritic suspensions and mixtures of these phases with tricalcium silicate was investigated. It was found that at elevated temperatures up to 150 ° C and pressures up to 50 MPa, an iron analogue of ettringite, hydrogarnets, calcium hydroalumoferrites C₃(A,F)H₆ and iron hydroxide are formed. In a mixture with tricalcium silicate, the hydrogen garnet contains silica, the proportion of which increases with temperature. The addition of silica also increases the proportion of the C-S-H phase. When added to the mixture, NaCl accelerates the hydration process. The iron analogue of ettringite was found to be more stable at elevated temperatures. The resulting hardened cement mortars had high strength and compensated shrinkage.

For citation: Krivoborodov Yu.R., Thet Nainh Myint. Stability of sulphoalumoferrite cement at increased temperature // Technique and technology of silicates. – 2020.Vol. 27, No4. – Pp 123 – 128.