scholarly journals ACCOUNTING OF SOLAR RADIATION IN NUMERICAL MODELLING OF THE THERMOPHYSICAL PROCESSES OF FREEZING AND THAWING OF PERMAFROST SOILS

2020 ◽  
Vol 11 (4) ◽  
pp. 20-32
Author(s):  
S. A Kudryavtsev ◽  
T. U Valtseva ◽  
A. V Kajarskii ◽  
J. I Kotenko ◽  
V. N Paramonov ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Permafrost Soil ◽  
Geographic Latitude ◽  
Freezing And Thawing ◽  
Local Conditions ◽  
Geological Conditions ◽  
Geographical Latitude ◽  
Permafrost Soils ◽  
Thawing Process ◽  
Reconstruction Period

The article considers options for stabilizing the thawing process of permafrost soil of railways during the reconstruction period. The analysis of the engineering and geological conditions made it possible to design rock cooling structures at this facility, which are berms and cover slopes of the subgrade with fractionated rocky soil. The technical characteristics of fractionated rock soil structures have been developed and tested in this cryological area and have shown their effective operation for more than 30 years. As a result of the operation of the railway embankment, permafrost degrades and its boundary is at different depths depending on local conditions and the condition of the drainage systems from the subgrade. The position of the upper permafrost boundary should be established during surveys, if it is not advisable to restore the frozen base to a depth of 10 m, it is necessary to strengthen the thawed weak base and create conditions for the consolidation of thawed soils. Geographic latitude determines zoning in the distribution of climate elements. Solar radiation enters the upper boundary of the atmosphere, depending on geographic latitude. It determines the midday height of the Sun and the duration of the radiation. The absorbed radiation is distributed more difficultly, since it depends on cloud cover, the albedo of the earth's surface, and the degree of transparency of the air. Zoning also underlies the distribution of air temperature. The temperature depends not only on the absorbed radiation, but also on the circulating conditions. Zoning in the temperature distribution leads to zoning of other meteorological climate values. The influence of geographical latitude on the distribution of meteorological values becomes more noticeable with height when the influence of other climate factors associated with the earth's surface weakens.

scholarly journals Analysis of the causes of engineering structures deformations at gas industry facilities in the permafrost zone

2021 ◽  
Vol 249 ◽  
pp. 377-385
Author(s):  
Gennadii Vasiliev ◽  
Anton Dzhaljabov ◽  
Igor Leonovich
Keyword(s):  
Multicomponent System ◽  
Individual Characteristics ◽  
Raw Material ◽  
Permafrost Zone ◽  
Permafrost Soil ◽  
Material Base ◽  
Engineering Structures ◽  
Gas Industry ◽  
Geological Conditions ◽  
Permafrost Soils

Construction of oil and gas infrastructure facilities on permafrost soils is the most important task of increasing the raw material base of the entire fuel and energy industry in Russia. Permafrost soil is a complex, multicomponent system, state of which depends on many factors. Buildings and structures built under such conditions, on the one hand, have a complex thermal effect on permafrost soils, and on the other hand, they perceive the consequences of changes in the characteristics of such soils. This situation leads to the fact that buildings and structures on permafrost soil during their life cycle are subject to complex and poorly predictable deformations. Article presents the results of a study for various degradation processes of permafrost soils that can be implemented at construction sites of industrial facilities. Analysis of the deformations causes for engineering structures at the gas industry in the permafrost zone is carried out. Series of reasons causing such deformations have been investigated. Comprehensive criterion for assessing changes in permafrost-geological conditions of industrial sites is proposed. It is suggested to apply the method of calculating the individual characteristics for the temperature regime of the territory to monitor and assess the conditions of heat exchange and predict changes in the geocryological conditions of permafrost soil.

scholarly journals Drivers of Spruce Bark Beetle (Ips typographus) Infestations on Downed Trees after Severe Windthrow

Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1290
Author(s):  
Branislav Hroššo ◽  
Pavel Mezei ◽  
Mária Potterf ◽  
Andrej Majdák ◽  
Miroslav Blaženec ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Bark Beetle ◽  
Bark Beetles ◽  
Ips Typographus ◽  
Wind Damage ◽  
Stem Length ◽  
Local Conditions ◽  
Spruce Bark Beetle ◽  
Management Actions ◽  
Spruce Bark

Research Highlights: Bark beetles are important agents of disturbance regimes in temperate forests, and specifically in a connected wind-bark beetle disturbance system. Large-scale windthrows trigger population growth of the European spruce bark beetle (Ips typographus L.) from endemic to epidemic levels, thereby allowing the killing of Norway spruce trees over several consecutive years. Background and Objectives: There is a lack of evidence to differentiate how outbreaks are promoted by the effects of environmental variables versus beetle preferences of trees from endemic to outbreak. However, little is known about how individual downed-tree characteristics and local conditions such as tree orientation and solar radiation affect beetle colonization of downed trees. Materials and Methods: To answer this question, we investigated the infestation rates and determined tree death categories (uprooted, broken, and stump) in wind-damaged areas in Western Tatra Mts. in Carpathians (Slovakia) from 2014–2016, following a windthrow in May 2014. In total, we investigated 225 trees over eight transects. For every tree, we measured its morphological (tree height, crown characteristics), environmental (solar radiation, terrain conditions, trunk zenith), temporal (time since wind damage), and beetle infestation (presence, location of attack, bark desiccation) parameters. We applied Generalized Additive Mixed Models (GAMM) to unravel the main drivers of I. typographus infestations. Results: Over the first year, beetles preferred to attack broken trees and sun-exposed trunk sides over uprooted trees; the infestation on shaded sides started in the second year along with the infestation of uprooted trees with lower desiccation rates. We found that time since wind damage, stem length, and incident solar radiation increased the probability of beetle infestation, although both solar radiation and trunk zenith exhibited nonlinear variability. Our novel variable trunk zenith appeared to be an important predictor of bark beetle infestation probability. We conclude that trunk zenith as a simple measure defining the position of downed trees over the terrain can anticipate beetle infestation. Conclusions: Our findings contribute to understanding of the bark beetle’s preferences to colonize windthrown trees in the initial years after the primary wind damage. Further, our findings can help to identify trees that are most susceptible to beetle infestation and to prioritize management actions to control beetle population while maintaining biodiversity.

scholarly journals Conditioning of excess activated sludge by freezing and thawing process

1987 ◽  
Vol 10 (3) ◽  
pp. 180-186,169 ◽  
Author(s):  
Tetsuo IDE ◽  
Kenji KAWASAKI ◽  
Hirotaka YAMASHIRO ◽  
Akira MATSUDA
Keyword(s):  
Activated Sludge ◽  
Freezing And Thawing ◽  
Thawing Process

scholarly journals Associations of Blood Pressure With Geographical Latitude, Solar Radiation, and Ambient Temperature: Results From the Chilean Health Survey, 2009–2010: Table 1.

2016 ◽  
Vol 183 (11) ◽  
pp. 1071-1073 ◽  
Author(s):  
Sebastián E. Cabrera ◽  
Jennifer S. Mindell ◽  
Mario Toledo ◽  
Miriam Alvo ◽  
Charles J. Ferro
Keyword(s):  
Blood Pressure ◽  
Solar Radiation ◽  
Ambient Temperature ◽  
Health Survey ◽  
Geographical Latitude

Volumetric Changes in Cells During Freezing and Thawing

1980 ◽  
Vol 102 (2) ◽  
pp. 91-97 ◽  
Author(s):  
J. M. Knox ◽  
G. S. Schwartz ◽  
K. R. Diller
Keyword(s):  
Experimental Data ◽  
Image Analysis ◽  
Close Agreement ◽  
Living Cells ◽  
Freezing Process ◽  
Freezing And Thawing ◽  
Image Analysis Technique ◽  
Computerized Image Analysis ◽  
Analysis Technique ◽  
Thawing Process

A thermodynamic model is presented to describe the combined freezing and thawing process for living cells. Continuous changes in the cell volume are predicted according to the thermal protocol imposed on the system. Experimental verification of the model is sought by monitoring continuously the volume of cells as frozen on a cryomicroscope. The volumes of individual cells are measured from sequential photomicrographs by a computerized image analysis technique. The model and experimental data are in quite close agreement for the freezing process, but upon thawing the experimentally measured volumes consistently increased much more rapidly than predicted by the model. The model can be made to conform to the data by accounting for a substantial influx of electrolyte to the cell at subfreezing temperatures.

scholarly journals Conditioning of excess activated sludge by freezing and thawing process -the effect of freeze rate-

1988 ◽  
Vol 11 (8) ◽  
pp. 520-526,496 ◽  
Author(s):  
Kenji KAWASAKI ◽  
Kazuhisa ISIKAWA ◽  
Hirotaka YAMASHIRO ◽  
Akira MATSUDA ◽  
Tetsuo IDE
Keyword(s):  
Activated Sludge ◽  
Freezing And Thawing ◽  
Thawing Process

75 GLUCOSE CONCENTRATION OF FREEZING EXTENDER MODULATES THE TYROSINE PHOSPHORYLATION PATTERN OF FROZEN-THAWED BOAR SPERMATOZOA

2009 ◽  
Vol 21 (1) ◽  
pp. 138
Author(s):  
J. E. Rodríguez-Gil ◽  
M. Hernández ◽  
M. M. Rivera ◽  
L. Ramió-Lluch ◽  
J. Ballester ◽  
...  
Keyword(s):  
Protein Phosphorylation ◽  
Tyrosine Phosphorylation ◽  
Glucose Concentration ◽  
Egg Yolk ◽  
Freezing And Thawing ◽  
Precise Control ◽  
Boar Sperm ◽  
Phosphorylation Pattern ◽  
Thawing Process ◽  
Boar Spermatozoa

The optimization of freezing extenders is an essential issue for enhancing boar sperm cryosurvival. The aim of the present study was to disclose the role of glucose concentration of freezing extender on the metabolic activity of frozen–thawed spermatozoa. To achieve it, pooled sperm-rich ejaculate fractions from 5 mature and fertile boars (3 ejaculates per boar) were collected using the gloved-hand method. After centrifugation (2400g for 3 min), the sperm pellet was split into 7 aliquots. The aliquots were diluted to a final concentration of 1 × 109 sperm mL–1, in a Tris-citric extender supplemented with 20% egg-yolk, 3% glycerol, and 0, 0.05, 2, 4, 10, 55, or 185 mm glucose. All the extenders were adjusted to a pH of 6.8 and 310 mOsm kg–1 to avoid osmolarity effects. Extended semen samples were dispensed into 0.5-mL straws, and frozen in a programmable cell freezer at 20°C min–1. Thawing was carried out in a water bath at 37°C for 20 s. Afterward, an analysis of protein phosphorylation in tyrosine residues was carried out through bi-dimensional electrophoresis followed by a Western blot analysis. This analysis indicated that sperm samples frozen in extenders without glucose showed specific changes in the tyrosine phosphorylation pattern compared with fresh sperm. Furthermore, the addition of glucose in increasing concentrations to the freezing extender was accompanied by a concentration-dependent decrease in the overall tyrosine phosphorylation pattern, especially in proteins with a molecular weight ranging from 150 to 200 kDa and an acidic isoelectric point (pI). The maximal decrease was observed in spermatozoa frozen in the extender containing 185 mm glucose, in which an additional decrease in the tyrosine phosphorylation of proteins ranging from 60 to 80 kDa, and a basic pI was also observed. These results suggest that glucose is a modulator in the resistance of boar sperm to support freezing and thawing process, because the precise protein phosphorylation pattern of spermatozoa is directly linked to their functional status. In this way, a precise control of the glucose concentration of the freezing extender would be required to improve boar sperm cryoresistance. Supported by CICYT (AGL2005-00760 and AGL2004-04756-C02-02/GAN), Madrid and GERM (04543/07), Murcia, Spain.

The effect of selenium supplementation on fresh and frozen ram semen

1996 ◽  
Vol 1996 ◽  
pp. 185-185
Author(s):  
Jennifer M.L. Anderson ◽  
R.F.E. Axford ◽  
I. Ap Dewi
Keyword(s):  
Liquid Nitrogen ◽  
Semen Quality ◽  
Selenium Supplementation ◽  
Freezing And Thawing ◽  
Frozen Semen ◽  
Thawing Process ◽  
Low Selenium

Previous research conducted on bulls, rats and man have shown that selenium-deficient animals produce less viable semen than animals of an adequate status, because the tail of the spermatozoa is a seleno-flagellate (Slaweta et al., 1988). Furthermore, the fertilising ability of ram spermatozoa is reduced in liquid nitrogen as the semen quality is affected by osmolality and the freezing and thawing process (Colas and Guerin, 1981). In a small experiment, the effect of selenium supplementation on low-selenium rams was tested to ascertain the quality and viability of fresh ram semen and the post-thaw recovery and fertilising ability of frozen semen.

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