scholarly journals On thermal effects of early structure formation of fluorogypsum composite binder

2020 ◽  
Vol 1611 ◽  
pp. 012048
Author(s):  
L A Anikanova ◽  
O V Volkova ◽  
A I Kudyakov ◽  
V A Lotov ◽  
E Danilova ◽  
...  
Keyword(s):  
Structure Formation ◽  
Thermal Effects ◽  
Composite Binder

scholarly journals ANALYSIS OF THERMAL EFFECTS WITH MULTI-FOCI STRUCTURING

2021 ◽  
pp. 89-99
Author(s):  
A.V. Kolesnikov ◽  
◽  
S.V. Semenova ◽  
V.N. Vyrovoy ◽  
V.Ya. Kersh ◽  
...  
Keyword(s):  
Structure Formation ◽  
Thermal Imaging ◽  
Thermal Effects ◽  
Thermal Sensitivity ◽  
Thermal Processes ◽  
Composite Binder ◽  
Indirect Response ◽  
Heterogeneous Processes ◽  
Exothermic Process ◽  
High Plastic

Abstract. The possibility of a thermal imaging technique for studying the setting of composite materials in the light of the paradigm of multifocal structure formation is analyzed. Since thermal violated observations are characterized by a high thermal sensitivity to temperature gradients up to hundredths of degrees, they make it possible to distinguish the temperature differences arising in the adjacent sections of the hardening binding. A technique for obtaining thermal images (thermograms) of a hardening composite binder is implemented. A series of thermograms of setting processes was obtained, for two of them a quantitative study was carried out, including the temperature gauge and the construction of several types of graphic mappings of the obtained patterns ‒ the normalized frequency of the distribution of the area of the binder for those temperatures and two types of densitograms ‒ radial and circular, allowing to visualize the structure of thermal foci arising in a binder. The hardening of binding materials is considered as a multistage exothermic process, in which hydration processes is accompanied by heating. The speed of heterogeneous processes associated with hydration depends, in turn, on the characteristics of the forming structure of binding materials. The observed thermal processes are considered as an indirect response, "shadow" of structure formation processes. The information consisting in this indirect response, however, is enough to make a number of conclusions on the nature of the emerging structure. The study revealed a high probability of the formation of foci near the macroscopic boundaries of the section (walls and bottom of the form), inconsistency of the structural processes, the occurrence of diverse foci of structure formation corresponding to temperature foci. The interpretation of the data obtained is the conclusion about formation of the regions of high plastic deformations near the boundaries of the contact of the foci. This regions are considered as a cluster of microscopic boundaries of the section, cracks and pores, which give rise to the structure of the destruction of the hardened material. The emergence of such areas is associated with nonynchronouspassage of structuring in different parts of the binder.

Structure Formation Features of Non-Autoclaved Gas Concrete Matrix on the Basis of Composite Binders with Various Mineral Additives

2019 ◽  
Vol 974 ◽  
pp. 249-254
Author(s):  
Michail V. Absimetov ◽  
Mikhail Yurievich Elistratkin ◽  
Marina S. Ageeva
Keyword(s):  
Structure Formation ◽  
Mutual Influence ◽  
Strength Properties ◽  
Mass Concrete ◽  
Composite Binder ◽  
Viscosity Change ◽  
Molding Compound ◽  
Scale Levels ◽  
Good Potential ◽  
Cellular Concrete

One of the effective ways to reduce the material consumption of structures, to save all types of resources due to this, is the transition to porous constructional materials instead of traditional dense materials. In this regard, non-autoclaved gas concrete is of great interest. This material has a high manufacturability and has a good potential for improving the strength properties due to the replacement of traditional portland cement by special composite binders. Available publications confirm the effectiveness and prospects of this direction. An important disadvantage of such works is the fact that the binder indicators and the final cellular concrete characteristics are considered mainly independently. In our opinion, it is more correct to consider at least two structure-forming processes proceeding in parallel and sequentially at different scale levels. Micro level is a stone structure formation based on the composite binder; macro-level is a gas porization of cellular mass concrete. These processes have a great mutual influence on each other, and therefore this article attempts to observe the gassing products effect on the stone hardening based on composite binders, as well as the composite binder makeup on the viscosity change of the molding compound, as an important condition for the formation of high-quality less defective pore structure of cellular concrete.

scholarly journals CEMENT STONE STRUCTURE COMPACTION WITH COMPOSITE BINDER

2019 ◽  
pp. 195-206 ◽  
Author(s):  
R. S. Fediuk ◽  
A. V. Baranov ◽  
D. V. Khromenok ◽  
I. R. Zelenskiy ◽  
S. V. Kim
Keyword(s):  
Portland Cement ◽  
Silicon Dioxide ◽  
Structure Formation ◽  
Quartz Sand ◽  
Strength Properties ◽  
Planetary Mill ◽  
Cement Stone ◽  
Composite Binder ◽  
Silica Additive

The aim of the paper is to improve the strength properties of cement stone via control for structure formation. The composite binder composition includes the type CEM I 42.5N (58–70%) Portland cement, active silica additive (25–37%), quartz sand (2.5–7.5%) and limestone crushed waste (2.5–7.5%). The optimum technology of mechanochemical activation is proposed for the cement stone. The optimization of the structure formation process is provided by the mineral-mineral modifier, crushed together with Portland cement in a planetary mill to a specific surface of 550 m2/kg. The amorphous phase of silicon dioxide in the composition of the modifier intensifies the calcium hydroxide binding forming during alite hydration. It contributes to the growth in low-basic calcium silicate and lowers the cement stone basicity, while reducing the amount of portlandite. The crystalline phase of β-quartz silicon dioxide plays the role of crystallization centers new formations and the cement stone microstructure compaction. Limestone particles contribute to the formation of calcium hydrocarbonate and act as a microfiller together with fine ground quartz sand clogging the pores in the cement stone.

Forecasting the Microstructure of a Microalloyed Steel Plate Strip

2021 ◽  
Vol 316 ◽  
pp. 306-312
Author(s):  
Sergey Platov ◽  
Konstantin Maslennikov ◽  
Nicolay Urtsev
Keyword(s):  
Structure Formation ◽  
Thermal Effects ◽  
Steel Plate ◽  
Thermomechanical Processing ◽  
Microalloyed Steel ◽  
Heat Removal ◽  
Structural Transformations ◽  
Point Of View ◽  
Plate Strip ◽  
Kinetics Of

A description of the experience in the development and implementation of a model for forecasting the microstructure of rolled tubular products steel during thermomechanical processing of a semi-finished product and the relative IT-solution for the plate mill 5000 of PJSC MMK is presented. This solution is based on modeling the kinetics of structure formation in the mill technological line. The article describes briefly the result of analysis of a number of existing kinetics models of phase and structural transformations from the point of view of their application under the conditions of interest to us. An empirical study of the thermal effects of phase transformations and the influence of the heat removal mode on the kinetics of structure formation is described. The process of development of an empirical kinetics model and implementation of IT-solution, that implements this model, is also described.

Thermal Considerations in Lens Regulator Systems

1970 ◽  
Vol 28 ◽  
pp. 358-359
Author(s):  
K.C. Newton
Keyword(s):  
Electron Microscope ◽  
Thermal Effects ◽  
Environmental Control ◽  
Reference Networks ◽  
Better Than

Thermal effects in lens regulator systems have become a major problem with the extension of electron microscope resolution capabilities below 5 Angstrom units. Larger columns with immersion lenses and increased accelerating potentials have made solutions more difficult by increasing the power being handled. Environmental control, component choice, and wiring design provide answers, however. Figure 1 indicates with broken lines where thermal problems develop in regulator systemsExtensive environmental control is required in the sampling and reference networks. In each case, stability better than I ppm/min. is required. Components with thermal coefficients satisfactory for these applications without environmental control are either not available or priced prohibitively.

Direct measurement of electron-diffraction-pattern intensities using an energy loss spectrometer

1989 ◽  
Vol 47 ◽  
pp. 668-669
Author(s):  
A. G. Jackson ◽  
M. Rowe
Keyword(s):  
Thermal Effects ◽  
Dynamic Range ◽  
Scattering Amplitude ◽  
Dynamical Theory ◽  
Site Symmetry ◽  
Proof Of Concept ◽  
Parallel Acquisition ◽  
Kinematic Approximation ◽  
Speed Up ◽  
Structure Calculations

Diffraction intensities from intermetallic compounds are, in the kinematic approximation, proportional to the scattering amplitude from the element doing the scattering. More detailed calculations have shown that site symmetry and occupation by various atom species also affects the intensity in a diffracted beam. [1] Hence, by measuring the intensities of beams, or their ratios, the occupancy can be estimated. Measurement of the intensity values also allows structure calculations to be made to determine the spatial distribution of the potentials doing the scattering. Thermal effects are also present as a background contribution. Inelastic effects such as loss or absorption/excitation complicate the intensity behavior, and dynamical theory is required to estimate the intensity value.The dynamic range of currents in diffracted beams can be 104or 105:1. Hence, detection of such information requires a means for collecting the intensity over a signal-to-noise range beyond that obtainable with a single film plate, which has a S/N of about 103:1. Although such a collection system is not available currently, a simple system consisting of instrumentation on an existing STEM can be used as a proof of concept which has a S/N of about 255:1, limited by the 8 bit pixel attributes used in the electronics. Use of 24 bit pixel attributes would easily allowthe desired noise range to be attained in the processing instrumentation. The S/N of the scintillator used by the photoelectron sensor is about 106 to 1, well beyond the S/N goal. The trade-off that must be made is the time for acquiring the signal, since the pattern can be obtained in seconds using film plates, compared to 10 to 20 minutes for a pattern to be acquired using the digital scan. Parallel acquisition would, of course, speed up this process immensely.

Social development of modern Russia: trends, risks, prospects

2018 ◽  
pp. 76-89
Author(s):  
E. M. Avraamova ◽  
V. N. Titov
Keyword(s):  
Middle Class ◽  
Social Development ◽  
Social Structure ◽  
Structure Formation ◽  
Resource Availability ◽  
Social Dynamics ◽  
Quantitative Estimation ◽  
Resource Potential ◽  
Institutional Conditions ◽  
Resource Characteristics

The analysis of present-time directions in the study of social development has allowed to identify the resource approach as the most productive one which enables to assess social dynamics through the range of resource characteristics of different population groups and abilities of the relevant groups to apply development resources in the current economic and institutional conditions. Basing on the sociological survey conducted by ISAP RANEPA, the quantitative estimation of material and social recourses of the population has been made; integral values of the resource potential have been calculated as well. The issues of social structure formation are analyzed through the aspect of resource availability; the barriers of Russian middle-class enlargement are defined.

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