scholarly journals Experimental studies of geomechanical processes in hard rock massif during blasting of explosive charge in different crosscut shape

2014 ◽  
Vol 8 (3) ◽  
pp. 373-379
Author(s):  
K Ishchenko ◽  
◽  
S Konoval ◽  
I Kratkovskyi ◽  
V Krukovska ◽  
...  
Keyword(s):  
Explosive Charge ◽  
Hard Rock ◽  
Experimental Studies ◽  
Rock Massif

scholarly journals Laws of gas draining in the massif disturbed by mining operations

2019 ◽  
Vol 109 ◽  
pp. 00047
Author(s):  
Serhii Kurnosov ◽  
Volodymyr Zerkal
Keyword(s):  
Strain State ◽  
Abutment Pressure ◽  
Gas Permeability ◽  
Experimental Studies ◽  
Rock Massif ◽  
Gas Release ◽  
Mining Operations ◽  
Stress Strain ◽  
Stress Strain State ◽  
The Impact

A method for calculating gas permeability of the rock massif depending on its stress-strain state is presented. By using methods of the mine experimental studies, influence of mining operations in the adjacent long walls on intensity of gas release from the previously worked-out long-pillar was determined, as well as impact of the massif stress-strain state on efficiency of the drainage boreholes. Formulas were obtained for calculating coefficients of the impact of zones with static and dynamic abutment pressure on intensity of gas draining in the previously worked-out long-pillar.

scholarly journals The specificities of deformations and failures of highly stressed hard rock massifs

2019 ◽  
Vol 129 ◽  
pp. 01010
Author(s):  
Anatolii Kozyrev ◽  
Eduard Kasparyan ◽  
Iuliia Fedotova ◽  
Nikolay Kuznetcov
Keyword(s):  
Hard Rock ◽  
Experimental Studies ◽  
Strain Curve ◽  
Tectonic Stress ◽  
Stress Fields ◽  
Mining Engineering ◽  
Deformation And Failure ◽  
Loading Mode ◽  
Dynamic Form ◽  
Very High

According to modern concepts, the state of highly stressed hard rock massifs is mostly caused by the effect of gravitational-tectonic stress fields. At that, a probability of brittle rock failure in a dynamic form is very high. Such failures are always accompanied by the significant energy release accumulated during the deformation process. Based on the experimental studies of deformation and failure processes in various types of rock samples from the Kola Peninsula deposits, we have proposed the criteria for classifying rocks as prone to rock bursts. The information for assessing the rock proneness to dynamic failures can be obtained by analysing the strain curve at the pre-peak section when tested on the ordinary presses and testing devices according to the standard methods. If we study the processes of rocks' deformation and energy accumulation under the triaxial loading mode, we can establish the parameters for the occurrence of dynamic failure of rocks. This, in turn, will allow identifying the conditions of such failure in the investigated rocks for a specific mining-engineering situation and, thereby, coming to a scientifically-based prediction of the rocks' proneness to dynamic rock pressure occurrences.

scholarly journals Complex spectral-acoustic monitoring of the state of fluid-saturated coal-rock mass

2020 ◽  
Vol 168 ◽  
pp. 00059
Author(s):  
Yurii Pylypenko ◽  
Iryna Konstantynova ◽  
Kchichtof Оzet
Keyword(s):  
Acoustic Emission ◽  
Roof Rock ◽  
Experimental Studies ◽  
Rock Massif ◽  
Complex Stressed State ◽  
Rock Destruction ◽  
Saturated Rock ◽  
Control Research ◽  
Coal Rock

Subject of the research is the methods for monitoring properties and state of coal-rock massif. This work is an experimental validation of the studied parameters of acoustic emission occurred during destruction of the roadway roof. Elements of the theory of acoustic emission control, research methods, results and experimental studies of the fluid-saturated rock destruction were studied. In this article, methods of studying and interpreting the results of geophysical observations of the process of the roof rock stratification and fall at caving of the undermined rocks at a complex stressed state are presented. Biseds, approaches to solving the problems of managing and controlling the dynamics of changes in the stress-strain state of the undermined fluid-saturated coal-rock massif based on factors of autocorrelation between the seismic-acoustic phenomena occurred over time are described. Experimental grounds are given to the complex control methods with determination of the level of disintegration by the Fourier estimation of the amplitude-frequency and amplitude-time spectra.

Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

1962 ◽  
Vol 14 ◽  
pp. 415-418
Author(s):  
K. P. Stanyukovich ◽  
V. A. Bronshten
Keyword(s):  
Explosive Charge ◽  
The Moon ◽  
Meteorite Impacts ◽  
The Earth ◽  
Lunar Craters ◽  
The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

3-D reconstruction and analysis of mammalian mitotic spindle structure

1992 ◽  
Vol 50 (1) ◽  
pp. 578-579
Author(s):  
Kent McDonald ◽  
David Mastronarde ◽  
Rubai Ding ◽  
Eileen O'Toole ◽  
J. Richard McIntosh
Keyword(s):  
Cross Sections ◽  
Mitotic Spindle ◽  
Experimental Studies ◽  
Video Camera ◽  
Three Dimensions ◽  
Mitotic Spindles ◽  
Black And White ◽  
Reconstruction Methods ◽  
Spindle Structure ◽  
Tissue Culture Line

Mammalian spindles are generally large and may contain over a thousand microtubules (MTs). For this reason they are difficult to reconstruct in three dimensions and many researchers have chosen to study the smaller and simpler spindles of lower eukaryotes. Nevertheless, the mammalian spindle is used for many experimental studies and it would be useful to know its detailed structure.We have been using serial cross sections and computer reconstruction methods to analyze MT distributions in mitotic spindles of PtK cells, a mammalian tissue culture line. Images from EM negatives are digtized on a light box by a Dage MTI video camera containing a black and white Saticon tube. The signal is digitized by a Parallax 1280 graphics device in a MicroVax III computer. Microtubules are digitized at a magnification such that each is 10-12 pixels in diameter.

Effects of Attachment Styles on the Experience of Equity in Heterosexual Couples Relationships

2003 ◽  
Vol 50 (4) ◽  
pp. 298-310 ◽  
Author(s):  
Ina Grau ◽  
Jörg Doll
Keyword(s):  
Attachment Theory ◽  
Attachment Style ◽  
Intimate Relationships ◽  
Attachment Styles ◽  
Experimental Studies ◽  
The Other ◽  
Heterosexual Couples ◽  
Secure Attachment ◽  
Dependent Variables ◽  
Equity Ratio

Abstract. Employing one correlational and two experimental studies, this paper examines the influence of attachment styles (secure, anxious, avoidant) on a person’s experience of equity in intimate relationships. While one experimental study employed a priming technique to stimulate the different attachment styles, the other involved vignettes describing fictitious characters with typical attachment styles. As the specific hypotheses about the single equity components have been developed on the basis of the attachment theory, the equity ratio itself and the four equity components (own outcome, own input, partner’s outcome, partner’s input) are analyzed as dependent variables. While partners with a secure attachment style tend to describe their relationship as equitable (i.e., they give and take extensively), partners who feel anxious about their relationship generally see themselves as being in an inequitable, disadvantaged position (i.e., they receive little from their partner). The hypothesis that avoidant partners would feel advantaged as they were less committed was only supported by the correlational study. Against expectations, the results of both experiments indicate that avoidant partners generally see themselves (or see avoidant vignettes) as being treated equitably, but that there is less emotional exchange than is the case with secure partners. Avoidant partners give and take less than secure ones.

Sign in / Sign up

Export Citation Format

Share Document