Effects of Zn/P ratio on the structures and properties of glasses with the general composition of (80-x)ZnO-20Fe2O3-xP2O5 (x=40, 45, 50, 55, 60) (molar fraction, %) were investigated. Glass structure was measure...Effects of Zn/P ratio on the structures and properties of glasses with the general composition of (80-x)ZnO-20Fe2O3-xP2O5 (x=40, 45, 50, 55, 60) (molar fraction, %) were investigated. Glass structure was measured by infrared absorption spectrum. Glass density (/9) was measured by the Archimedes method. Coefficients of thermal expansion (a) and characterization temperature were obtained by a dilatometer. Water durability of each glass was estimated from the dissolution rate (DR)in water at 90 ℃ for 24 h. With increasing Zn/P ratio, water durability of zinc-iron phosphate glasses increases dramatically without large increase in the characterization temperature. (80-x)ZnO-20Fe2O3-xP2O5 glasses with 0.3≤Zn/P≤0.5 are suit for low-to-mid temperature sealing application for substrates with a〈8.0× 10^-6℃^-1.展开更多
The Jesuits played an important role in the transmission of Western science and technology to China during the seventeenth and eighteenth centuries,though their impact on water technology has received scant attention ...The Jesuits played an important role in the transmission of Western science and technology to China during the seventeenth and eighteenth centuries,though their impact on water technology has received scant attention thus far.As a case in point,Sabatino de Ursis,Society of Jesus熊三拔,in collaboration with the Chinese official Xu Guangqi徐光啟,published in 1612 Hydraulic Methods of the Far West(Taixi shuifa泰西水法),the earliest book in China on Western water-lifting devices,which contained a detailed description of the Archimedean screw pump.While the impact of the Archimedean screw pump in China and Korea remained rather limited,the screw pump was used to drain water from gold mines in the Japanese Sado Island from as early as 1637.This fact became known in the West only in the very late 1800s when hand-colored picture scrolls about the Japanese gold mining process became available.These scrolls show various applications of Archimedean screw,which apparently were made according to the manufacturing instructions in Hydraulic Methods of the Far West.展开更多
The spiral has been studied for the first time in the book “About the spirals”, by Archimedes (Greece, 287-212 BC). In America, the design of spirals seems to have been used previous to Archimedes' time, although...The spiral has been studied for the first time in the book “About the spirals”, by Archimedes (Greece, 287-212 BC). In America, the design of spirals seems to have been used previous to Archimedes' time, although in the Northwest of Argentina the appearance of this figure in ceramics can be dated between the years 800 and 1,400 (AD). The spiral is found in cave paintings, in pumpkin carvings and in pottery, particularly those painted inside of plates (pucos in Quechua language).There can be seen simple linear spirals, double spirals and spirals filled with squares, spirals in two, facing each other symmetrically, as well as spirals joined to bodies of animals. The number of spires detected in the largest spiral is 12, a number of evidently sacred characteristics. When there are several spirals in an earthenware vessel, it can be seen that all of them spin to the same side whether it is clockwise or not. This could have been caused by the predominance of the use of either one hand or the other by the ancient artist. This paper is produced with computer methods used to design spirals in the computer, either Archimedes or the logarithmic ones. Finally, the book: “Man and his symbols” of the psychiatrist Carl Gustav Jung (1875-1961) help to understand this congruencies. In this paper, Mathematics is complemented with the Archeology of art and Psychology.展开更多
基金Project(7602110340) supported by the Postdoctoral Science Foundation of Central South University, ChinaProject(721500277)supported by the Fundamental Research Funds for the Central Universities of China
文摘Effects of Zn/P ratio on the structures and properties of glasses with the general composition of (80-x)ZnO-20Fe2O3-xP2O5 (x=40, 45, 50, 55, 60) (molar fraction, %) were investigated. Glass structure was measured by infrared absorption spectrum. Glass density (/9) was measured by the Archimedes method. Coefficients of thermal expansion (a) and characterization temperature were obtained by a dilatometer. Water durability of each glass was estimated from the dissolution rate (DR)in water at 90 ℃ for 24 h. With increasing Zn/P ratio, water durability of zinc-iron phosphate glasses increases dramatically without large increase in the characterization temperature. (80-x)ZnO-20Fe2O3-xP2O5 glasses with 0.3≤Zn/P≤0.5 are suit for low-to-mid temperature sealing application for substrates with a〈8.0× 10^-6℃^-1.
文摘The Jesuits played an important role in the transmission of Western science and technology to China during the seventeenth and eighteenth centuries,though their impact on water technology has received scant attention thus far.As a case in point,Sabatino de Ursis,Society of Jesus熊三拔,in collaboration with the Chinese official Xu Guangqi徐光啟,published in 1612 Hydraulic Methods of the Far West(Taixi shuifa泰西水法),the earliest book in China on Western water-lifting devices,which contained a detailed description of the Archimedean screw pump.While the impact of the Archimedean screw pump in China and Korea remained rather limited,the screw pump was used to drain water from gold mines in the Japanese Sado Island from as early as 1637.This fact became known in the West only in the very late 1800s when hand-colored picture scrolls about the Japanese gold mining process became available.These scrolls show various applications of Archimedean screw,which apparently were made according to the manufacturing instructions in Hydraulic Methods of the Far West.
文摘The spiral has been studied for the first time in the book “About the spirals”, by Archimedes (Greece, 287-212 BC). In America, the design of spirals seems to have been used previous to Archimedes' time, although in the Northwest of Argentina the appearance of this figure in ceramics can be dated between the years 800 and 1,400 (AD). The spiral is found in cave paintings, in pumpkin carvings and in pottery, particularly those painted inside of plates (pucos in Quechua language).There can be seen simple linear spirals, double spirals and spirals filled with squares, spirals in two, facing each other symmetrically, as well as spirals joined to bodies of animals. The number of spires detected in the largest spiral is 12, a number of evidently sacred characteristics. When there are several spirals in an earthenware vessel, it can be seen that all of them spin to the same side whether it is clockwise or not. This could have been caused by the predominance of the use of either one hand or the other by the ancient artist. This paper is produced with computer methods used to design spirals in the computer, either Archimedes or the logarithmic ones. Finally, the book: “Man and his symbols” of the psychiatrist Carl Gustav Jung (1875-1961) help to understand this congruencies. In this paper, Mathematics is complemented with the Archeology of art and Psychology.