scholarly journals Влияние критических параметров технологии на свойства композитов на основе портландитовой матрицы

2020 ◽  
Vol 45 (4) ◽  
Author(s):  
Keyword(s):  
Experimental Studies ◽  
Mineralogical Composition ◽  
Critical Parameters ◽  
Pressing Pressure ◽  
Factors Affecting ◽  
X Ray ◽  
The Matrix ◽  
Matrix Substance ◽  
Contact Condensation ◽  
Hardening System

Представлены результаты экспериментальных исследований критических параметров технологии на свойства контактно-конденсационных бесклинкерных систем твердения на основе портландитовой матрицы и алюмосиликатного наполнителя. В исследованиях в качестве алюмосиликатного наполнителя использовался трепел. Выявлены основные факторы, влияющие на свойства изделий, полученных по технологии контактно-конденсационного твердения. К ним относятся прежде всего характеристики наполнителя (минералогический состав, тонкость помола) и параметры технологии (соотношение матрицы и наполнителя, величина прессового давления). С помощью рентгенофазового анализа установлено, что минералогический состав выбранного алюмосиликатного компонента (трепела) позволяет получать композиты по контактно-конденсационной технологии. Получены количественные данные о влиянии соотношения матрицы и наполнителя и величины прессового давления на прочность композита разных сроков твердения. Структура этого композита состоит из кристаллических сростков в основном матричной субстанции с присутствием низкоосновных гидросиликатов и гидроалюминатов кальция. Установлено, что оптимальный расход наполнителя составляет 15–30% от массы матрицы, давление прессования – 80 МПа. Ключевые слова: портландитовая матрица, алюмосиликатный компонент, контактно-конденсационная технология, бесклинкерная система твердения, диаграмма Исикавы, прессовое давление. The results of experimental studies of critical parameters of the technology on the properties of contact-condensation linker-free hardening systems based on portlandite matrix and aluminosilicate filler are presented. The flutter was used as an alumosilicate filler in studies. The main factors affecting on properties of the products obtained with the contact-condensation hardening technology have been revealed. These include, first of all, the characteristics of the filler (mineralogical composition, fineness of grinding) and the technology parameters (matrix to filler ratio, press pressure). Using X-ray phase analysis, it was found that the mineralogical composition of the selected aluminosilicate component (trepel) allows to obtain the composites using contact-condensation technology. The quantitative data on effect of matrix-filler ratio and press pressure value on strength of obtained composite in different hardening periods are obtained. The structure of this composite consists of crystalline splices in the main matrix substance the portlandite with the presence of lowbase hydrosilicates and calcium hydroaluminates. It has been established that the optimal flow rate of the filler is 15–30% of the mass of the matrix, the pressing pressure is 80 MPa. Keywords: portlandite matrix, aluminosilicate component, contact-condensation technology, linkless hardening system, Ishikawa diagram, press pressure

scholarly journals THE RESULTS OF THE STUDY OF THE INFLUENCE OF THE OPERATING CONDITIONS OF THE TURBOCHARGER ON ITS PERFORMANCE

2021 ◽  
pp. 70-74
Author(s):  
Aynur Galimov ◽  
Ilgiz Galiev ◽  
Bulat Ziganshin ◽  
Rail Khusainov ◽  
Al'bert Muhametshin
Keyword(s):  
Pressure Drop ◽  
Experimental Studies ◽  
The State ◽  
Operating Conditions ◽  
Lubrication System ◽  
Factors Affecting ◽  
The Matrix ◽  
Lubrication Mode ◽  
Bearing Assembly ◽  
Main Factors

The operability of the bearing assembly, which ensures the operation of the turbocharger at different speeds of its rotor, determines the reliability of the turbocharger as a whole. In this regard, the condition of the turbocharger bearing assembly determines the performance of the entire turbocharger. The purpose of the research is to justify the parameter that determines the performance of the turbocharger and a comparative assessment of changes in the state of turbochargers with a standard lubrication system and when using individual bearing assembly lubrication systems. The main factors affecting the state of the turbocharger bearing assembly, and hence the length of the rotor rotation by inertia after the engine stops, are considered to be: the increase in the clearance in the bearing assembly, the speed of rotation of the turbocharger rotor before the engine stops, and the time of pressure drop in the bearing assembly to zero after the engine stops. To obtain dependences describing the effect of the gap in the turbocharger bearing, the time of pressure drop in its lubrication system after the engine stops, and the change in the duration of rotation of the turbocharger rotor by inertia in dynamics, we conducted experimental studies. The experiment involved vehicles with a standard lubrication system and with an individual lubrication system for the turbocharger bearing assembly. The data was sample along the main diagonal of the matrix of experimental indicators. The dependences of the effect of the gap and the time of pressure drop in the bearing assembly on the duration of rotation of the rotor of the turbocharger by inertia after stopping the engine, at the speed of rotation of the rotor before stopping the engine 10000, 25000 and 40000 min-1 are obtained. A comparative analysis of this indicator is given for turbochargers with a standard and individual lubrication system of the bearing assembly, which shows that the duration of rotation of the rotor by inertia increases from 45 s (standard lubrication mode) to 90 s (with an individual lubrication system). This gives us reason to believe that the wear rate of the bearing will decrease by half during operation

scholarly journals Petrography And Field Study Of Andesitic Ignimbrite In Temangan, Kelantan

2021 ◽  
Vol 72 ◽  
pp. 223-232
Author(s):  
Nur Shafiqah Shahman ◽  
◽  
Elvaene James ◽  
Arham Muchtar Achmad Bahar ◽  
Muhammad Irfan Hadhi ◽  
...  
Keyword(s):  
Volcanic Rocks ◽  
Alkali Feldspar ◽  
Mineralogical Composition ◽  
Intimate Relationship ◽  
Thrust Fault ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Matrix ◽  
Two Stages ◽  
Plagioclase Textures

The volcanic rocks in Temangan, Kelantan consist of felsic to intermediate volcanic rocks, that is mainly of pyroclastic with rhyolitic, dacitic, and andesitic tuff. A geological review has been carried out in Kampung Bukit Besi, Temangan, in Kelantan, Malaysia, which is composed of schist, shale, andesite, and ignimbrite. In Temangan, andesite and ignimbrite show an intimate relationship, as the ignimbrite exists as the fragments and andesite as the matrix. The methodology used in this study are petrography and X-ray Diffraction (XRD) analyses, to determine the mineralogical composition of andesitic ignimbrite. Andesite shows aphenitic and porphyritic textures and consist of pyroxene, plagioclase, alkali feldspar, quartz, biotite and iron oxides. A range of plagioclase textures indicate imperfect equilibrium condition from andesite, reflecting plagioclase dissolution and regrowth. The structural analysis suggest that thrust fault occurred in the study area. Andesite and ignimbrite of the two stages are suggested to have derived from the andesite magma eruption which produced pyroclastic flow eruptions in small amount in most caldera volcanoes at high temperature gradient.

Lateral resolution of the electron microbeam analysis

1978 ◽  
Vol 36 (1) ◽  
pp. 542-543
Author(s):  
H.J. Dudek
Keyword(s):  
Quantitative Analysis ◽  
Depth Resolution ◽  
Lateral Resolution ◽  
Cylindrical Particle ◽  
Correction Procedure ◽  
X Ray ◽  
Element Concentrations ◽  
Microbeam Analysis ◽  
The Matrix

The chemical inhomogenities in modern materials such as fibers, phases and inclusions, often have diameters in the region of one micrometer. Using electron microbeam analysis for the determination of the element concentrations one has to know the smallest possible diameter of such regions for a given accuracy of the quantitative analysis.In th is paper the correction procedure for the quantitative electron microbeam analysis is extended to a spacial problem to determine the smallest possible measurements of a cylindrical particle P of high D (depth resolution) and diameter L (lateral resolution) embeded in a matrix M and which has to be analysed quantitative with the accuracy q. The mathematical accounts lead to the following form of the characteristic x-ray intens ity of the element i of a particle P embeded in the matrix M in relation to the intensity of a standard S

Analysis and lattice imaging of a transitional event on garnets

1978 ◽  
Vol 36 (1) ◽  
pp. 270-271
Author(s):  
J.Y. Laval
Keyword(s):  
Yttrium Iron Garnet ◽  
Reciprocal Lattice ◽  
Transitional Zone ◽  
Lattice Imaging ◽  
Yttrium Iron ◽  
X Ray ◽  
Ionic Process ◽  
The Matrix ◽  
High Resolution Technique ◽  
Iron Garnet

The exsolution of magnetite from a substituted Yttrium Iron Garnet, containing an iron excess may lead to a transitional event. This event is characterized hy the formation of a transitional zone at the center of which the magnetite nucleates (Fig.1). Since there is a contrast between the matrix and these zones and since selected area diffraction does not show any difference between those zones and the matrix in the reciprocal lattice, it is of interest to analyze the structure of the transitional zones.By using simultaneously different techniques in electron microscopy, (oscillating crystal method microdiffraction and X-ray microanalysis)one may resolve the ionic process corresponding to the transitional event and image this event subsequently by high resolution technique.

Phase identification in SiC whisker reinforced Al2O3-R2O3-based composites

1992 ◽  
Vol 50 (1) ◽  
pp. 152-153
Author(s):  
C.M. Sung ◽  
K.J. Ostreicher ◽  
M.L. Huckabee ◽  
S.T. Buljan
Keyword(s):  
Analytical Electron Microscopy ◽  
Phase Identification ◽  
Reinforced Composites ◽  
Ion Milling ◽  
X Ray ◽  
Binary Oxides ◽  
Analytical Electron ◽  
The Matrix ◽  
Second Phases ◽  
Convergent Beam

A series of binary oxides and SiC whisker reinforced composites both having a matrix composed of an α-(Al, R)2O3 solid solution (R: rare earth) have been studied by analytical electron microscopy (AEM). The mechanical properties of the composites as well as crystal structure, composition, and defects of both second phases and the matrix were investigated. The formation of various second phases, e.g. garnet, β-Alumina, or perovskite structures in the binary Al2O3-R2O3 and the ternary Al2O3-R2O3-SiC(w) systems are discussed.Sections of the materials having thicknesses of 100 μm - 300 μm were first diamond core drilled. The discs were then polished and dimpled. The final step was ion milling with Ar+ until breakthrough occurred. Samples prepared in this manner were then analyzed using the Philips EM400T AEM. The low-Z energy dispersive X-ray spectroscopy (EDXS) data were obtained and correlated with convergent beam electron diffraction (CBED) patterns to identify phase compositions and structures. The following EDXS parameters were maintained in the analyzed areas: accelerating voltage of 120 keV, sample tilt of 12° and 20% dead time.

Improving x-ray map resolution with image restoration techniques

1996 ◽  
Vol 54 ◽  
pp. 598-599
Author(s):  
Richard B. Mott ◽  
John J. Friel ◽  
Charles G. Waldman
Keyword(s):  
Image Restoration ◽  
Hubble Space Telescope ◽  
Extensive Literature ◽  
Small Object ◽  
X Rays ◽  
X Ray ◽  
Mapping Parameters ◽  
The Matrix ◽  
The 1960S ◽  
Map Resolution

X-rays are emitted from a relatively large volume in bulk samples, limiting the smallest features which are visible in X-ray maps. Beam spreading also hampers attempts to make geometric measurements of features based on their boundaries in X-ray maps. This has prompted recent interest in using low voltages, and consequently mapping L or M lines, in order to minimize the blurring of the maps.An alternative strategy draws on the extensive work in image restoration (deblurring) developed in space science and astronomy since the 1960s. A recent example is the restoration of images from the Hubble Space Telescope prior to its new optics. Extensive literature exists on the theory of image restoration. The simplest case and its correspondence with X-ray mapping parameters is shown in Figures 1 and 2.Using pixels much smaller than the X-ray volume, a small object of differing composition from the matrix generates a broad, low response. This shape corresponds to the point spread function (PSF). The observed X-ray map can be modeled as an “ideal” map, with an X-ray volume of zero, convolved with the PSF. Figure 2a shows the 1-dimensional case of a line profile across a thin layer. Figure 2b shows an idealized noise-free profile which is then convolved with the PSF to give the blurred profile of Figure 2c.

DIESEL ENGINE OPERATION IN USE OF FUEL WITH ADDITIVES

2018 ◽  
pp. 18-24
Author(s):  
Petar Kazakov ◽  
Atanas Iliev ◽  
Emil Marinov
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Diesel Fuel ◽  
Internal Combustion Engines ◽  
Experimental Studies ◽  
Combustion Engines ◽  
Engine Operation ◽  
Factors Affecting ◽  
Operating Modes ◽  
Positive Effects

Over the decades, more attention has been paid to emissions from the means of transport and the use of different fuels and combustion fuels for the operation of internal combustion engines than on fuel consumption. This, in turn, enables research into products that are said to reduce fuel consumption. The report summarizes four studies of fuel-related innovation products. The studies covered by this report are conducted with diesel fuel and usually contain diesel fuel and three additives for it. Manufacturers of additives are based on already existing studies showing a 10-30% reduction in fuel consumption. Comparative experimental studies related to the use of commercially available diesel fuel with and without the use of additives have been performed in laboratory conditions. The studies were carried out on a stationary diesel engine СМД-17КН equipped with brake КИ1368В. Repeated results were recorded, but they did not confirm the significant positive effect of additives on specific fuel consumption. In some cases, the factors affecting errors in this type of research on the effectiveness of fuel additives for commercial purposes are considered. The reasons for the positive effects of such use of additives in certain engine operating modes are also clarified.

ADOLESCENTS IN CRIMINAL STREET GROUPINGS: REASONS AND MOTIVATIONS

2019 ◽  
Vol 29 (2) ◽  
pp. 195-199
Author(s):  
E.O. Chernova
Keyword(s):  
At Risk ◽  
Preventive Measures ◽  
Experimental Studies ◽  
Motivational Factors ◽  
Social Motives ◽  
Factors Affecting ◽  
Social Communities ◽  
Criminal Groups

The article gives an analysis of the results of authorial experimental studies. Motivational factors affecting adolescents' participation in criminal groups are considered, they are: dominant groups of motives, the predominance of aspiration to success or avoidance of failures. Thus, the author explores the subjective potential of the personality of adolescent groupers. According to the results of the research, the author concludes that the specificity of the motivation of such adolescents consists in the predominance of material motives, social motives (involvement in social communities, groupings) and motives of recognition and respect. The author notes that the motivation for avoiding failures is more characteristic of such adolescents than the motivation for the pursuit of success. It is concluded that the data obtained can serve as a basis for developing preventive measures when working with adolescents at risk.

The methodology of experimental research of the feed components extrusion process in order to improve its energy performance

2020 ◽  
pp. 147-152
Author(s):  
E. M. Ratnikov ◽  
D. O. Milko
Keyword(s):  
Experimental Studies ◽  
Energy Performance ◽  
Extrusion Process ◽  
Mathematical Methods ◽  
Screw Extruder ◽  
Mathematical Planning ◽  
Factors Affecting ◽  
Extrusion Processing ◽  
Definition Of

Annotation Purpose. Development of a program and methods for conducting experimental studies of the extrusion process with the definition of parameters and modes of operation of the extruder to improve its energy performance. Methods. Methods of mathematical statistics, synthesis, analysis, description and modeling were used. Results. The application of mathematical methods, in particular mathematical planning, reduces the number of experiments several times, and allows to evaluate the role of influencing factors, obtain a mathematical model of the process and determine the optimal conditions for its parameters and modes, etc. Conclusions. The methodology for experimental studies of a screw extruder is presented with the necessary equipment and methodology for processing the obtained experimental data. A mathematical method of planning, which reduces the number of experiments several times, allows us to evaluate the role of factors affecting productivity and energy intensity is presented. Keywords: extruder, auger, nutrients, research methodology, extrusion, processing, feed.

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