Direct visualization of colloid transport across a natural heterogeneous fractured rock surface

A novel approach called the YUV dimension method is proposed in this study to indirectly characterize fractured rock surface topography. This model is based on YUV color model theory in iconography and graphics. The process is described in detail as follows. A true-color photo with m pixels is selected. Y is denoted by gray scale, U by hue, and V by the saturation components of the pixel color. These components are applied to create the z, x and y coordinates of the point in the coordinate system that originates from the pixel. A similar method is applied in each pixel. M points are created in the coordinate space. The number of created points is equivalent to one of the pixels. The m points are then connected and a rough YUV surface is established. Otherwise, the calculation method for the self-affine dimension of a n - 1 ~ n-dimensional fractal body is presented by fractal Brownian motion theory and then degenerated to one between the 2D and 3D case. The approach is applied to evaluate the dimension of the YUV surface, i.e. the YUV dimension. To validate the feasibility of YUV dimension theory, numerical studies on the YUV dimension are conducted through a laser profilometer scanning experiment and scanning electron microscopy with the same specimens. The surface characteristics of similar samples are analyzed by probing into the YUV, general and grayscale dimensions of the specimens. The comparison shows that the YUV and general dimensions of similar specimens are fundamentally identical, and the complete trends of the YUV and gray dimensions remain consistent with changing specimens. The result indicates that YUV dimension theory is reasonable and feasible. In short, the YUV dimension is a new method that exhibits more advantages than the general and grayscale dimensions. This method characterizes surface configuration indirectly.

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Ground vibration generated by hydraulic rock breakers and its impact on the safety of nearby earthfill dam in a graphite mine

Quarterly Journal of Engineering Geology and Hydrogeology ◽

10.1144/qjegh2020-113 ◽

2021 ◽

pp. qjegh2020-113

Author(s):

C. Sawmliana ◽

R. K. Singh ◽

P. Hembram ◽

Orizen MS Dawngliana

Keyword(s):

Structural Damage ◽

Impact Analysis ◽

Fractured Rock ◽

Ground Vibration ◽

Rock Surface ◽

Mining Activities ◽

Ground Vibrations ◽

Fractured Rock Mass ◽

The Stability ◽

Explosive Chemicals

A detailed impact analysis on the effects of non-explosive chemicals and hydraulic rock breakers at a graphite mine in India close to an irrigation dam was carried out in this study. The dam was 70 m away from the mining lease boundary. When a single hydraulic rock breaker worked on fractured rock mass, the magnitude of ground vibration recorded at 10 m on the same working bench was 2.37 mm/s but, when it worked on fresh rock surface, the ground vibration at 9 m on the same working bench was 4.67 mm/s. Beyond 35 m on the same bench, no ground vibrations were recorded. Ground vibrations generated by three jack hammer drilling machines operating simultaneously on the same working bench was less than 0.5 mm/s when measured at 7.2 m distance. The combined effect on the magnitudes of ground vibrations by two hydraulic rock breakers operating simultaneously on the same bench 6 m apart was found to be negligible. The ground vibrations generated by hydraulic rock breakers and other mining activities were found to be lower than required to cause any structural damage or threat to the stability to the dam.

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Experimental Study on the Thermal Infrared Spectral Variation of Fractured Rock

Remote Sensing ◽

10.3390/rs13061191 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1191

Author(s):

Jianwei Huang ◽

Shanjun Liu ◽

Wenfang Liu ◽

Chunju Zhang ◽

Shuiping Li ◽

...

Keyword(s):

Fractured Rock ◽

Thermal Infrared ◽

Spectral Radiance ◽

Rock Surface ◽

Spectral Variation ◽

Remote Sensing Technology ◽

Sensing Technology ◽

Different Types ◽

Infrared Spectral ◽

Thermal Infrared Radiation

Previous studies have shown that thermal infrared radiation (TIR) anomalies occur in the vicinity of fractures that form when a rock is loaded to failure. Different types of fracturing modes correspond to different TIR anomaly trends. However, the spectral features and the mechanisms responsible for the TIR changes in the fracturing stage remain poorly understood. In this paper, experiments involving observations of the thermal infrared spectrum (8.0–13.0 μm) of loaded sandstone during the fracturing stage were conducted under outdoor conditions. The experiment yielded the following results: (1) Different fracturing modes can lead to different trends in the spectral radiance variation; (2) when an extensional fissure appeared on the rock surface, the radiance increased with a local peak in the 8.0–9.7 μm range; 3) when local bulging formed at the surface, the radiance decreased, with a local valley in the 8.0–9.7 μm range. The radiance variation caused by morphologic changes is the combined result of changes in both the temperature and the emissivity. The characteristic waveband corresponding to the reststrahlen features (RF) of quartz was mainly related to the emissivity change. This study provides a preliminary experimental foundation for the detection of crustal surface fractures via satellite-based remote sensing technology.

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Development of Experimental Instrumentation for Measurement of Advection in Narrow Aperture in Granite Block

Journal of Nuclear Engineering and Radiation Science ◽

10.1115/1.4041790 ◽

2019 ◽

Vol 5 (3) ◽

Author(s):

Jaroslav Kotowsk ◽

Tomáš Černoušek ◽

Filip Jankovský ◽

Pavel Kůs ◽

Petr Polívka ◽

...

Keyword(s):

Fractured Rock ◽

Three Dimensional ◽

Precise Determination ◽

Rock Surface ◽

Flow Paths ◽

The Czech Republic ◽

Geological Repository ◽

Ideal Tool ◽

Full Volume

A granite block, acquired from a quarry Panská Dubenka located in the Czech Republic and used in presented experiments, is part of the same bedrock that can be potentially used for a deep geological repository. It is important to characterize advection in fractured rock to assess possible groundwater contamination. Newly used method—three-dimensional scanning using Hexagon Romer Arm was implemented to characterize the morphology of an examined fractured block with a aperture. The scanning technology provides the possibility to digitalize the rock surface. The scanning can be also used to determine any changes in the rock surface. The block was instrumented by tubing, and the aperture was sealed using a silicone. Flow paths were investigated by the comparison of fluid weights on the outlet on every output/site. The Hexagon Romer Arm is an ideal tool for the precise determination of a aperture's width in its full volume.

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Direct visualization of phase-separated domains in lipid membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082315 ◽

1978 ◽

Vol 36 (2) ◽

pp. 290-291

Author(s):

S. W. Hui ◽

T. P. Stewart

Keyword(s):

Lipid Membranes ◽

Structural Information ◽

Freeze Fracture ◽

Biological Molecules ◽

Vacuum Drying ◽

Direct Visualization ◽

X Ray Diffraction ◽

Electron Microscopic ◽

X Ray ◽

Hydrocarbon Chains

Direct electron microscopic study of biological molecules has been hampered by such factors as radiation damage, lack of contrast and vacuum drying. In certain cases, however, the difficulties may be overcome by using redundent structural information from repeating units and by various specimen preservation methods. With bilayers of phospholipids in which both the solid and fluid phases co-exist, the ordering of the hydrocarbon chains may be utilized to form diffraction contrast images. Domains of different molecular packings may be recgnizable by placing properly chosen filters in the diffraction plane. These domains would correspond to those observed by freeze fracture, if certain distinctive undulating patterns are associated with certain molecular packing, as suggested by X-ray diffraction studies. By using an environmental stage, we were able to directly observe these domains in bilayers of mixed phospholipids at various temperatures at which their phases change from misible to inmissible states.

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