Ice surface gravity survey in river and lake areas and its applications

2018 ◽  
Author(s):  
Yang Zhanjun ◽  
Li Dechun ◽  
Li keyi ◽  
Li Zhao
Keyword(s):  
Surface Gravity ◽  
Gravity Survey ◽  
Ice Surface

Performing a High Resolution surface Gravity Survey to Monitor the Gas Cap Water Injection Project, Prudhoe Bay, Alaska

2002 ◽  
Author(s):  
Jerry L. Brady ◽  
John F. Ferguson ◽  
Carlos V.L. Aiken ◽  
John E. Seibert ◽  
Tianyou Chen ◽  
...  
Keyword(s):  
High Resolution ◽  
Water Injection ◽  
Surface Gravity ◽  
Gravity Survey ◽  
Prudhoe Bay

UNDERGROUND AND SURFACE GRAVITY SURVEY, LEADWOOD, MISSOURI

Geophysics ◽  
1961 ◽  
Vol 26 (2) ◽  
pp. 158-168 ◽  
Author(s):  
S. T. Algermissen
Keyword(s):  
Surface Gravity ◽  
Gravity Survey ◽  
The North ◽  
Anomalous Density ◽  
Principal Factors ◽  
Mine Workings ◽  
Four Square

A surface gravity survey consisting of 214 stations covering approximately four square miles was conducted over and adjacent to the North Leadwood Mines at Leadwood, Missouri. A corresponding survey of 278 stations was carried out in the mine workings. A method of reducing underground gravity observations is outlined. The principal factors limiting the accuracy of the underground observations are given. Methods for determining rock densities are described. A comparison of the surface and underground gravity maps shows that major Precambrian knobs were revealed by both surveys. Smaller structures not shown on the surface map were revealed by the underground survey. Anomalous density areas between the level of the two surveys were easily located.

A seafloor and sea surface gravity survey of Axial Volcano

1990 ◽  
Vol 95 (B8) ◽  
pp. 12751 ◽  
Author(s):  
John A. Hildebrand ◽  
J. Mark Stevenson ◽  
Philip T. C. Hammer ◽  
Mark A. Zumberge ◽  
Robert L. Parker ◽  
...  
Keyword(s):  
Sea Surface ◽  
Surface Gravity ◽  
Gravity Survey ◽  
Axial Volcano

Discrimination of monomer from multimer DNA disk-shaped toruses by freezeetch TEM

1984 ◽  
Vol 42 ◽  
pp. 210-211
Author(s):  
George C. Ruben ◽  
Kenneth A. Marx
Keyword(s):  
Biochemical Data ◽  
Dna Structures ◽  
Ice Surface ◽  
Double Stranded Dna ◽  
Data Support ◽  
Dna Organization ◽  
Trivalent Cations

In vitro collapse of DNA by trivalent cations like spermidine produces torus (donut) shaped DNA structures thought to have a DNA organization similar to certain double stranded DNA bacteriophage and viruses. This has prompted our studies of these structures using freeze-etch low Pt-C metal (9Å) replica TEM. With a variety of DNAs the TEM and biochemical data support a circumferential DNA winding model for hydrated DNA torus organization. Since toruses are almost invariably oriented nearly horizontal to the ice surface one of the most accessible parameters of a torus population is annulus (ring) thickness. We have tabulated this parameter for populations of both nicked, circular (Fig. 1: n=63) and linear (n=40: data not shown) ϕX-174 DNA toruses. In both cases, as can be noted in Fig. 1, there appears to be a compact grouping of toruses possessing smaller dimensions separated from a dispersed population possessing considerably larger dimensions.

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

An Analytical Thermodynamic Approach to Friction of Rubber on Ice

2012 ◽  
Vol 40 (2) ◽  
pp. 124-150
Author(s):  
Klaus Wiese ◽  
Thiemo M. Kessel ◽  
Reinhard Mundl ◽  
Burkhard Wies
Keyword(s):  
Coefficient Of Friction ◽  
Liquid Layer ◽  
Contact Area ◽  
Leading Edge ◽  
Viscous Friction ◽  
Analytical Approximation ◽  
Real Contact Area ◽  
Length Scales ◽  
Real Contact ◽  
Ice Surface

ABSTRACT The presented investigation is motivated by the need for performance improvement in winter tires, based on the idea of innovative “functional” surfaces. Current tread design features focus on macroscopic length scales. The potential of microscopic surface effects for friction on wintery roads has not been considered extensively yet. We limit our considerations to length scales for which rubber is rough, in contrast to a perfectly smooth ice surface. Therefore we assume that the only source of frictional forces is the viscosity of a sheared intermediate thin liquid layer of melted ice. Rubber hysteresis and adhesion effects are considered to be negligible. The height of the liquid layer is driven by an equilibrium between the heat built up by viscous friction, energy consumption for phase transition between ice and water, and heat flow into the cold underlying ice. In addition, the microscopic “squeeze-out” phenomena of melted water resulting from rubber asperities are also taken into consideration. The size and microscopic real contact area of these asperities are derived from roughness parameters of the free rubber surface using Greenwood-Williamson contact theory and compared with the measured real contact area. The derived one-dimensional differential equation for the height of an averaged liquid layer is solved for stationary sliding by a piecewise analytical approximation. The frictional shear forces are deduced and integrated over the whole macroscopic contact area to result in a global coefficient of friction. The boundary condition at the leading edge of the contact area is prescribed by the height of a “quasi-liquid layer,” which already exists on the “free” ice surface. It turns out that this approach meets the measured coefficient of friction in the laboratory. More precisely, the calculated dependencies of the friction coefficient on ice temperature, sliding speed, and contact pressure are confirmed by measurements of a simple rubber block sample on artificial ice in the laboratory.

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