This paper describes the effects of igneous intrusions on pore structure and adsorption capacity of the Permian coals in the Huaibei Coalfield, China. Twelve coal samples were obtained at different distances from a ~120 m extremely thick sill. Comparisons were made between unaltered and heat-affected coals using geochemical data, pore-fracture characteristics, and adsorption properties. Thermal alteration occurs down to ~1.3 × sill thickness. Approaching the sill, the vitrinite reflectance (R o) increased from 2.30% to 2.78%, forming devolatilization vacuoles and a fine mosaic texture. Volatile matter (VM) decreased from 17.6% to 10.0% and the moisture decreased from 3.0% to 1.6%. With decreasing distance to the sill, the micropore volumes initially increased from 0.0054 cm3/g to a maximum of 0.0146 cm3/g and then decreased to 0.0079 cm3/g. The results show that the thermal evolution of the sill obviously changed the coal geochemistry and increased the micropore volume and adsorption capacity of heat-affected coal (60–160 m from the sill) compared with the unaltered coals. The trap effect of the sill prevented the high-pressure gas from being released, forming gas pocket. Mining activities near the sill created a low pressure zone leading to the rapid accumulation of methane and gas outbursts in the Haizi Mine. PMID:24723841
Jiang, Jingyu; Cheng, Yuanping
This paper describes the effects of igneous intrusions on pore structure and adsorption capacity of the Permian coals in the Huaibei Coalfield, China. Twelve coal samples were obtained at different distances from a ~120 m extremely thick sill. Comparisons were made between unaltered and heat-affected coals using geochemical data, pore-fracture characteristics, and adsorption properties. Thermal alteration occurs down to ~1.3 × sill thickness. Approaching the sill, the vitrinite reflectance (R(o)) increased from 2.30% to 2.78%, forming devolatilization vacuoles and a fine mosaic texture. Volatile matter (VM) decreased from 17.6% to 10.0% and the moisture decreased from 3.0% to 1.6%. With decreasing distance to the sill, the micropore volumes initially increased from 0.0054 cm(3)/g to a maximum of 0.0146 cm(3)/g and then decreased to 0.0079 cm(3)/g. The results show that the thermal evolution of the sill obviously changed the coal geochemistry and increased the micropore volume and adsorption capacity of heat-affected coal (60-160 m from the sill) compared with the unaltered coals. The trap effect of the sill prevented the high-pressure gas from being released, forming gas pocket. Mining activities near the sill created a low pressure zone leading to the rapid accumulation of methane and gas outbursts in the Haizi Mine.
Sheriff, M.; Stevens, J.; Radue, M. J.; Strand, P.; Zhou, W.; Putnam, A. E.
The focus of our team's research is to study patterns of glacier retreat in the Northern and Southern Hemispheres at the end of the last ice age. Our purpose is to search for what caused this great global warming. Such information will improve understanding of how the climate system may respond to the human-induced buildup of fossil carbon dioxide. To reconstruct past glacier behavior, we sample boulders deposited by glaciers to find the rate of ancient recession. Each sample is tested to determine the age of the boulder using 10Be cosmogenic-nuclide dating. My portion of this research focuses on creating 3D models of the sampled boulders. Such high-resolution 3D models afford visual inspection and analysis of each boulder in a virtual reality environment after fieldwork is complete. Such detailed virtual reconstructions will aid post-fieldwork evaluation of sampled boulders. This will help our team interpret 10Be dating results. For example, a high-resolution model can aid post-fieldwork observations, and allow scientists to determine whether the rock has been previously covered, eroded, or moved since it was deposited by the glacier, but before the sample was collected. Also a model can be useful for recognizing patterns between age and boulder morphology. Lastly, the models can be used for those who wish to review the data after publication. To create the 3D models, I will use Hero4 GoPro and Canon PowerShot digital cameras to collect photographs of each boulder from different angles. I will then process the digital imagery using `structure-from-motion' techniques and Agisoft Photoscan software. All boulder photographs will be synthesized to 3D and based on a standardized scale. We will then import these models into an environment that can be accessed using cutting-edge virtual reality technology. By producing a virtual archive of 3D glacial boulder reconstructions, I hope to provide deeper insight into geological processes influencing these boulders during and since their deposition, and ultimately to improve methods that are being used to develop glacial histories on a global scale.
With the proton beam of the Hamburg isochronous cyclotron (HAIZY) thin uranium targets with the mass numbers 235, 236, and 238 were bombarded. Both fragments from the fission of the Np reaction systems and the neutrons coincident with the fragments were detected in the plane perpendicular to the beam direction. Measured and stored event by event were for all particles the times of flight. The detection of the neutron succeeded in conventional time-of-flight technique with NE213 liquid scintillators. A fission detector system with plastic scintillator foils was developed. It permits high event rates over long measuring times and allows the choice of so long neutron flight paths that a neutron energy resolution between 2% and 4% could be reached. The determination of the fragment masses is in spite of the short flight paths of 15 respectively 21 cm possible to +-2 amu. The isotropic component das discussed under the assumption that it is composed of prefission and scission neutrons which were emitted befor fission respectively during the fragmentation. From the post fission results the distribution of the excitation energy to both fragments was determined in dependence of Esup(*) and the fragment mass. (orig./HSI) [de
Full Text Available Understanding how mining-induced strata movement, fractures, bed separation, and ground subsidence evolve is an area of great importance for the underground coal mining industry, particularly for disaster control and sustainable mining. Based on the rules of mining-induced strata movement and stress evolution, accumulative dilatation of mining-induced unloading rock mass is first proposed in this paper. Triaxial unloading tests and theoretical calculation were used to investigate the influence of elastic dilatation of mining-induced unloading rock mass on the development of bed separation in the context of district No. 102 where a layer of super-thick igneous sill exists in the Haizi colliery. It is shown that the elastic dilatation coefficient of mining-induced unloading hard rocks and coal were 0.9~1.0‰ and 2.63‰ respectively under the axial load of 16 MPa, which increased to 1.30~1.59‰ and 4.88‰ when the axial load was 32 MPa. After successively excavating working faces No. 1022 and No. 1024, the elastic dilatation of unloading rock mass was 157.9 mm, which represented approximately 6.3% of the mining height, indicating the elastic dilatation of mining-induced unloading rock mass has a moderate influence on the development of bed separation. Drill hole detection results after grouting, showed that only 0.33 m of the total grouting filling thickness (1.67 m was located in the fracture zone and bending zone, which verified the result from previous drill hole detection that only small bed separation developed beneath the igneous sill. Therefore, it was concluded that the influences of elastic dilatation of mining-induced unloading rock mass and bulking of caved rock mass jointly contributed to the small bed separation space beneath the igneous sill. Since the accurate calculation of the unloading dilatation of rock mass is the fundamental basis for quantitative calculation of bed separation and surface subsidence, this paper is expected
Huang Guobin, also known as Laurence K. P. Wong, is a Hong Kong writer. He has, to date, published 15 collections of poems, seven collections of essays, and 11 monographs in literary criticism and translation studies, as well as translations of two literary works, The Divine Comedy(translated from the original Italian)and Hamlet, both of them fully annotated. All in all, even though his emphases may vary, he has brought under his jurisdiction the various types of writing d escribed in Western literary theory(poetry, prose, narrative, and so on)and the styles mentioned in the chapter“Ti xing”(‘Style and Temperament’)in Wenxin diaolong(The Literary Mind and the Carving of Dragons). Natural scenery, astronomy, his country and people, romance, kin relationships, and friendships, as well as literature and art, science and technology, all provide him with an inexhaustible source of material to draw on. The title of his first book is!Pan yuegui de haizi(The Child Who Plucks the Laurel,1975), in which“pan,”also meaning“climb,”is the key to understanding him. He is a remarkable mountain climber and swimmer, and once practised karate. He is full of vim and vigour, which he brings to bear on his studies and writing activities. Dedicated to scaling the heights of literature, he has written numerous sublime long poems as well as essays in the grand style, attaining an outstanding level of excellence, which can be described, in Liu Xie’s words, as“perspicacity like the sun and moon hanging in the sky, language like the fecund mountains and seas.”He has a good command of seven foreign languages, has imbibed the quintessence of literature, is well versed in learning, whether ancient or modern, Chinese or Western, and has a superior style of classical elegance of his own. His works are marked by compactness of texture, richness of content, and a multitudinous diversity, embracing both masculine grandeur and delicate beauty. In the world of literature in