14 Result(s)
within
Article
A. A. Krasnovsky
-
Article
Stress State of Support System in Temporary Roadway in Unstable Rock Mass
The authors estimate stress state in the support system and in rocks nearby a roadway driven in unstable rock mass and when the voids and cavities in the roadway roof are filled with hardening foam. The calcul...
-
Article
Kinetic Measurements of Singlet Oxygen Phosphorescence in Hydrogen-Free Solvents by Time-Resolved Photon Counting
Solvents lacking hydrogen atoms are very convenient models for elucidating the properties of singlet oxygen, since the lifetime of singlet oxygen in these solvents reaches tens milliseconds. Measuring intrinsi...
-
Article
Stress state of rocks surrounding excavations under variable Young’s modulus
Deep-level mining needs extra data on physical behavior of rocks at great depths (under high stresses). Without such data, any computations for deep-level technologies based on analogy with shallowdepth techno...
-
Article
Accounting for depth-wise linear change of stresses in the intact rock mass in geomechanical problems
The authors discuss formulation of boundary conditions in problems on stress-strain state of rocks around an underground excavation. The classical formulations neglect the presupposition of linearity of stress...
-
Article
New approach to measurement of IR absorption spectra of dissolved oxygen molecules based on photochemical activity of oxygen upon direct laser excitation
Generation of singlet oxygen upon excitation of oxygen molecules with IR diode lasers has been studied in organic media (carbon tetrachloride and acetone) saturated with air under normal pressure and temperatu...
-
Article
Mathematical modeling of rock specimen deformation
Among the aspects of modeling mathematically deformation of rock specimens, the article analyzes soft and stiff loading. The authors formulate an inverse problem on identification of mechanical properties, bou...
-
Article
Damage accumulation in a piecewise-homogeneous rock block under compression
The damage accumulation in a rock mass is conventionally monitored using rock specimens that are subjected to gradually growing compression for acoustic emission recording. The research problem is to establish...
-
Article
On the mechanism of photosensitized luminescence of singlet oxygen dimols in air-saturated pigment solutions
Luminescence of singlet oxygen dimols (1O2)2 was studied in aerobic solutions of a nonfluorescent photosensitizer phenalenone in CCl4 and C6F6 using a setup with a mechanical phosphoroscope and relatively low rat...
-
Article
Identification of weakenings in a rock block
The authors propose a process for identification of a weakening location in a rock block and the algorithm of its numerical realization based on the direct problem solutions and complementary data on boundary ...
-
Article
Primary mechanisms of photoactivation of molecular oxygen. History of development and the modern status of research
This review starts from a brief historical account devoted to the principles of the Bach-Engler peroxidation theory and experiments and ideas which led A. N. Bach to its creation. Then, the discovery of photod...
-
Article
Molecular arrangement of pigment-protein complex of photosystem 1
The circular dichroism (CD) method was applied to study the molecular organization of P700, antenna chlorophyll and protein of photosystem 1 complexes (CP1), isolated from chloroplasts under mild treatment wit...
-
Article
Some remarks on the origin and evolution of photosynthesis
-
Article
Chemical evolution of photosynthesis
The principles of biological evolution of photosynthesis are established, but the ways of chemical evolution are unclear yet. The model systems will help to elucidate the problem. Every type of photosynthesis ...
-
Article
Pathways of chemical evolution of photosynthesis
The primary metabolism of protobionts was probably based on the electron transfer reactions regulated by catalysts or photosensitizing pigments. The action of photoreceptive pigments was inevitable in the case...
