CO2 geosequestration is currently considered to be the most effective and economical method to dispose of artificial greenhouse gases. There are a large number of coal mines that will be scrapped, and some of them are located in deep formations in China. CO2 storage in abandoned coal mines will be a potential option for greenhouse gas disposal. However, CO2 trapping in deep coal pillars would i...

The secondary lamellae of the gill filaments are the sites of gas exchange in fish gills. They are mainly composed of 2 epithelial sheets joined together by pillar cells. These cells are characterized by collagen columns contained in infoldings of the cell membrane and oriented perpendicular to the epithelial sheets. The gill is the first organ to which the blood flows from the heart and within...

A radial stagnation-point flow cell utilizing an optical microscope and an image-capturing device was used to directly observe the deposition kinetics of colloidal particles onto micropatterned glass surfaces with well-defined surface charge features. Surface charge heterogeneity was microfabricated onto glass surfaces by silanizing specified regions of the glass surface by a soft lithographic ...

The properties and behaviour of an  colony Ti-6242 alloy have been investigated at 20C utilising coupled micro-pillar stress relaxation tests and computational crystal plasticity. The -phase slip strength and intrinsic slip system strain rate sensitivity have been determined, and the -phase shown to have stronger rate sensitivity than that for the  phase. Close agreement of experimental o...

The collapse of abandoned room-and-pillar mines is often violent and unpredictable. Safety concerns often resulted in mine closures with no post-mining stability evaluations. As a result, large amounts of land resources over room-and-pillar mines are wasted. This paper attempts to establish an understanding of the long-term stability issues of goafs (abandoned mines). Considering progressive pi...

The fundamental processes that govern plasticity and determine strength in crystalline materials at small length scales have been studied for over fifty years. Recent studies of single-crystal metallic pillars with diameters of a few tens of micrometres or less have clearly demonstrated that the strengths of these pillars increase as their diameters decrease, leading to attempts to augment exis...

Original scientific paper To enhance underground mining safety, researchers developed high-water and fast-setting cement (HWFSC). HWFSC essentially consists of two components and can be mixed with large quantities of water. To determine its mechanical strength, a series of uniaxial compressive strength tests were conducted on HWFSC specimens with different water-to-solid ratios. Results indicat...

Room-and-pillar mining is commonly employed for the extraction of rock salt in underground mines. Pillar stress a major concern these mines as it directly related to stability and mineral recovery. In this study flat jack method was used measure pillar stresses three Pakistan. The field work included determination in-situ stress, elastic modulus, recording variables (pillar length width, height...

Pillar is a part of the deposition excavated material that left behind to sustain rock weight above it. The aim this study was determine effect height and diameter ratio on strength pillar obtained from uniaxial compressive testing numerical modeling. Laboratory test results showed pillars with 1.5 H/D did not show an increase in 1.83%, while 1 gave more significant strength, which 32.99%. mode...