The physical-mechanical properties of Populus x canadensis Moench and Populus x euramericana (Dode) Guinier cv. Gelrica were studied to provide theoret- ical and scientific bases for the directional breeding and eff...The physical-mechanical properties of Populus x canadensis Moench and Populus x euramericana (Dode) Guinier cv. Gelrica were studied to provide theoret- ical and scientific bases for the directional breeding and efficient use of artificial forests with P. canadensis and P. euramericana Gelrica. The results showed the air-dried density, basic density of P. canadensis were 0.468 g/cm3 and 0.372 g/cm3, respectively; the shrinkage coefficient of radial, tangential and volume were 0.133%, 0.270% and 0.553%, respectively;the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 302.99 MPa, 79.69 MPa and 40.32 Mpa, respectively. As for the P. euramericana Gelrica, the air-dried density, basic densitywere 0.453 and 0.355 g/cm3, respectively; the shrink- age coefficient of radial, tangential and volume were 0.205%, 0.304% and 0.554%, respectively; the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 014.44, 55.87 and 33.09 Mpa respectively. Comprehensive analysis of the indicators showed that the properties of P. canadensis were better than those of P.euramericana Gelrica.展开更多
The tradition of serving trees has a long history in the Caucasus and therefore there is quite a long tradition of interest in these problems by different authors, including foreign scientists. The tradition starts wi...The tradition of serving trees has a long history in the Caucasus and therefore there is quite a long tradition of interest in these problems by different authors, including foreign scientists. The tradition starts with Apollonius of Rhodes. Since then it has been the field of permanent interest by scientists. The material presented in the report, that brings forward the specific practical aspects of sacral functions of sacral trees and forests and mainly deals with the mountainous part of Georgia (both East and West Georgia) and represents an attempt to compare Georgian ethnographic data with the materials found in Georgia by German scientists of the same period, which allows of drawing similarities and differences between these two sources of data. C. Hahn--a public figure living on the verge of the 19th-20th century, who had original material from Khevsureti and Svaneti, was chosen from German scientists. The first and important function is the connection of sacral trees with the world of the dead, which has a practical implication rather than a religious-ritual function, which is confirmed by the use of sacral forests as a burying place and for a ritual related to the dead; The second practical aspect of the sacral trees was their healing function. The purpose of the trees is established in the ethnographic material found virtually throughout the entire Caucasus. According to ethnographic data, there appears another function of sacral trees and forests. People used to gather there in order to solve important issues and reconcile conflicting parties. Sacred forests were a nature reserve for animal habitat and a kind of a haven for the people who, for some reason, had to shelter themselves in forests.展开更多
文摘The physical-mechanical properties of Populus x canadensis Moench and Populus x euramericana (Dode) Guinier cv. Gelrica were studied to provide theoret- ical and scientific bases for the directional breeding and efficient use of artificial forests with P. canadensis and P. euramericana Gelrica. The results showed the air-dried density, basic density of P. canadensis were 0.468 g/cm3 and 0.372 g/cm3, respectively; the shrinkage coefficient of radial, tangential and volume were 0.133%, 0.270% and 0.553%, respectively;the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 302.99 MPa, 79.69 MPa and 40.32 Mpa, respectively. As for the P. euramericana Gelrica, the air-dried density, basic densitywere 0.453 and 0.355 g/cm3, respectively; the shrink- age coefficient of radial, tangential and volume were 0.205%, 0.304% and 0.554%, respectively; the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 014.44, 55.87 and 33.09 Mpa respectively. Comprehensive analysis of the indicators showed that the properties of P. canadensis were better than those of P.euramericana Gelrica.
文摘The tradition of serving trees has a long history in the Caucasus and therefore there is quite a long tradition of interest in these problems by different authors, including foreign scientists. The tradition starts with Apollonius of Rhodes. Since then it has been the field of permanent interest by scientists. The material presented in the report, that brings forward the specific practical aspects of sacral functions of sacral trees and forests and mainly deals with the mountainous part of Georgia (both East and West Georgia) and represents an attempt to compare Georgian ethnographic data with the materials found in Georgia by German scientists of the same period, which allows of drawing similarities and differences between these two sources of data. C. Hahn--a public figure living on the verge of the 19th-20th century, who had original material from Khevsureti and Svaneti, was chosen from German scientists. The first and important function is the connection of sacral trees with the world of the dead, which has a practical implication rather than a religious-ritual function, which is confirmed by the use of sacral forests as a burying place and for a ritual related to the dead; The second practical aspect of the sacral trees was their healing function. The purpose of the trees is established in the ethnographic material found virtually throughout the entire Caucasus. According to ethnographic data, there appears another function of sacral trees and forests. People used to gather there in order to solve important issues and reconcile conflicting parties. Sacred forests were a nature reserve for animal habitat and a kind of a haven for the people who, for some reason, had to shelter themselves in forests.