ELLIPSOMETRIC STUDY OF THE ICE SURFACE STRUCTURE JUST BELOW THE MELTING POINT

1987 ◽  
Vol 48 (C1) ◽  
pp. C1-495-C1-501 ◽  
Author(s):  
Y. FURUKAWA ◽  
M. YAMAMOTO ◽  
T. KURODA
Keyword(s):  
Melting Point ◽  
Surface Structure ◽  
Ice Surface ◽  
Ellipsometric Study

scholarly journals Research on the Tunnel Excavated In Urumqi Glacier No. 1, Tianshan Glaciological Station, China

1987 ◽  
Vol 33 (113) ◽  
pp. 99-104 ◽  
Author(s):  
Huang Maohuan ◽  
Wang Zhongxiang
Keyword(s):  
Melting Point ◽  
Shear Strain ◽  
Maximum Shear Strain ◽  
Ice Surface ◽  
Basal Sliding ◽  
Glacier Ice ◽  
Glacier Motion

AbstractA tunnel was excavated in Urumqi Glacier No. 1, at the Tianshan Glaciological Station. Ice temperature, ice displacement, deformation, and basal sliding, etc. were observed at regular intervals. It is shown that the temperature near the glacier bed is close to the melting point and that the largest proportion of the overall glacier motion is within the lowermost ice layers. The glacier ice is in a state of compression. The maximum shear strain increases towards the entrance of the tunnel, corresponding to the change in slope of the ice surface, and also towards the bedrock.

Ellipsometric Study on Size-Dependent Melting Point of Nanometer-Sized Indium Particles

2016 ◽  
Vol 120 (19) ◽  
pp. 10686-10690 ◽  
Author(s):  
Jinbo Zhang ◽  
Yuxiang Zheng ◽  
Dongdong Zhao ◽  
Shangdong Yang ◽  
Liao Yang ◽  
...  
Keyword(s):  
Melting Point ◽  
Size Dependent ◽  
Ellipsometric Study

Friction on Ice

1988 ◽  
Vol 61 (1) ◽  
pp. 14-35 ◽  
Author(s):  
Asahiro Ahagon ◽  
Toshio Kobayashi ◽  
Makoto Mlsawa
Keyword(s):  
Melting Point ◽  
Energy Loss ◽  
Solubility Parameter ◽  
Low Temperatures ◽  
Fluid Layer ◽  
Frictional Resistance ◽  
High Viscosity ◽  
Polymer Chains ◽  
Solid Surfaces ◽  
Ice Surface

Abstract The friction on ice is strongly dependent on temperature. At sufficiently low temperatures, the frictional resistance on ice is high comparable to those on wet or even dry solid surfaces. As temperature rises and approaches the melting point of ice, however, friction rapidly decreases. Differing from the friction of a rubber on ordinary dry or wet solid surfaces the energy loss processes in the rubber do not seem to be the direct source of the frictional resistance on ice. Although frictional melting of ice could occur at high sliding speeds, an ice surface is inherently lubricated with a persistent mobile fluid layer at relatively high temperatures, near the melting point of ice. When a rubber slides on an ice surface, the fluid layer is sheared and undergoes drag flow. The energy loss process necessary for the frictional resistance takes place primarily in the fluid layer, and not in the rubber. The frictional resistance on ice is primarily determined by the viscosity and the thickness of the lubricating fluid layer. What is required of a rubber for better traction under such a condition is that the rubber surface follows the topography of the ice surface as closely as possible, so that more patches of ice surface can be sheared. Therefore, the rubber has to be sufficiently soft to show high friction on ice. Further improvement of the friction could be obtained by making it more resilient. Thus, a rubber with high friction on ice must be compounded so that the polymer chains maintain a high level of mobility at moderately low temperatures. This can be achieved by using polymers with low glass-transition-temperatures. An increased softener loading level helps to improve friction, but to a limited extent. In order to take maximum advantage of softeners, the choice of softener system is important. A relation common to all the mixed softener systems, except the ones containing high-viscosity softeners, was found to exist between the friction on ice and the solubility parameter of the softener mixture in the rubber. The friction on ice was maximized by selecting a softener system with a solubility parameter near that of the polymers in the rubber. The solubility parameter dependence of the friction was consistent with those of softness and resilience.

scholarly journals Excess Pressure Observed in a Water-filled Cavity in Athabasca Glacier, Canada

1970 ◽  
Vol 9 (55) ◽  
pp. 103-107 ◽  
Author(s):  
W.S.B. Paterson ◽  
J.C. Savage
Keyword(s):  
Melting Point ◽  
Excess Pressure ◽  
Ice Surface ◽  
Pressure Melting

AbstractDuring drilling in the Athabasca Glacier in April 1968, a cavity containing water was punctured at a depth of 9.2 m below the ice surface. Upon removing the drill, water gushed from the bore hole for about 55 s indicating an excess pressure of at least 0.25 bar within the cavity. The surrounding ice was slightly below the pressure melting point, and the excess pressure was apparently generated by the reduction in volume of the cavity caused by freezing of some of the water within it.

Real fibre diameters from freeze-etched Pt-C replicated fibre images: A DNA study

1984 ◽  
Vol 42 ◽  
pp. 684-685
Author(s):  
George C. Ruben ◽  
Kenneth A. Marx
Keyword(s):  
Surface Structure ◽  
Reliable Method ◽  
Cellular Origin ◽  
Ice Surface ◽  
Double Helices ◽  
Surface Detail ◽  
Filament Surface

Not only is recognition of characteristic filament surface structure important in identifying filaments of cellular origin but so is a reliable method for accurately measuring real filament width. Although a number of methods have been reported for estimating filament diameters these replication techniques are inappropriate for resolving filament surface detail to 12Å. To investigate how Pt-C metal replication changes the thickness of single or paired tightly wrapped hydrated DNA double helices, we have measured fibres with their long axis oriented (±5°) in the direction of metal replication in freeze-etched preparations. These fibres are coated with metal on both sides of their upper surface and are suspended horizontally above the ice surface over unshadowed regions so that both fibre edges are clearly delineated. The materials and methods have been described previously.

V.—Glacier Granule-markings

1910 ◽  
Vol 7 (3) ◽  
pp. 112-114 ◽  
Author(s):  
R. M. Deeley
Keyword(s):  
Surface Structure ◽  
Polarized Light ◽  
Plaster Of Paris ◽  
Ice Surface ◽  
Glacier Ice

I have already described the granular appearance of glacier ice as seen in polarized light and also the striations on the granules as shown by pencil rubbings. Last summer I succeeded in obtaining exact reproductions, in plaster of Paris, of the ice surface-structure in the upper cave in the Rhone Glacier. These are shown in Figs. 1–3.

scholarly journals Excess Pressure Observed in a Water-filled Cavity in Athabasca Glacier, Canada

1970 ◽  
Vol 9 (55) ◽  
pp. 103-107 ◽  
Author(s):  
W.S.B. Paterson ◽  
J.C. Savage
Keyword(s):  
Melting Point ◽  
Excess Pressure ◽  
Ice Surface ◽  
Pressure Melting

Abstract During drilling in the Athabasca Glacier in April 1968, a cavity containing water was punctured at a depth of 9.2 m below the ice surface. Upon removing the drill, water gushed from the bore hole for about 55 s indicating an excess pressure of at least 0.25 bar within the cavity. The surrounding ice was slightly below the pressure melting point, and the excess pressure was apparently generated by the reduction in volume of the cavity caused by freezing of some of the water within it.

scholarly journals Research on the Tunnel Excavated In Urumqi Glacier No. 1, Tianshan Glaciological Station, China

1987 ◽  
Vol 33 (113) ◽  
pp. 99-104 ◽  
Author(s):  
Huang Maohuan ◽  
Wang Zhongxiang
Keyword(s):  
Melting Point ◽  
Shear Strain ◽  
Maximum Shear Strain ◽  
Ice Surface ◽  
Basal Sliding ◽  
Glacier Ice ◽  
Glacier Motion

AbstractA tunnel was excavated in Urumqi Glacier No. 1, at the Tianshan Glaciological Station. Ice temperature, ice displacement, deformation, and basal sliding, etc. were observed at regular intervals. It is shown that the temperature near the glacier bed is close to the melting point and that the largest proportion of the overall glacier motion is within the lowermost ice layers. The glacier ice is in a state of compression. The maximum shear strain increases towards the entrance of the tunnel, corresponding to the change in slope of the ice surface, and also towards the bedrock.

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