Sediment source area of early cambrian stone coal in Northeastern Hunan Province, China

There were a variety of high content elements associated with the early Cambrian stone coal in northeastern Hunan province, and the attribute characteristics were distinct. In order to find out the sedimentary sources of stone coal in this area, the contents of major elements and trace elements in 12 stone coal samples were determined by X-ray fluorescence spectrometer (XRF) and inductively coupled plasma mass spectrometer (ICP–MS). Based on the combination of major elements, content characteristics of trace elements, distribution characteristics of rare earth elements and geochemical parameters of related elements, the source regions of the early Cambrian stone coal deposits in northeast Hunan province were discussed. The results showed that the early Cambrian stone coal in northeast Hunan province was mainly composed of inorganic minerals, and the content of SiO2 was the highest in the stone coal. The relationships between SiO2 and other major elements (and other major elements) were not obvious, and the quartz mineral morphology was characterized by terrigenous input. The trace elements (V, As, Sr, Mo, Cd, Sb, Ba, Bi, U) in stone coal were obviously enriched. The distribution characteristics of rare earth elements and the relationship between Nb/Y–Zr/TiO2 indicated that stone coal was influenced by neutral rock. LaN/YbN indicated that the deposition rate of stone coal deposits decreases from southeast to northwest. Means, the source comes from the eastern and southern directions; The w(SiO2)/w(Al2O3), w(Al2O3)/w(Al2O3+Fe2O3), w(Al)/w(Al+Fe+Mn) and K2O/Na2O–SiO2 structural discrimination models showed that the early Cambrian stone coal was deposited in the continental margin area, mainly receiving continental sources. Based on the comparison with the contents of rare earth elements, Rb, Nb and Pb in the middle-acid rocks of Shangshu Group distributed in the southeast direction of the study area, and the contents and combination characteristics of major elements in the magmatic rocks of Shuangxiwu Group, and combined with the evolution history of Jiangnan Orogenic belt, the middle-acid rock belt developed in the southeastern margin of Jiangnan orogenic belt was considered to be the source region of the early Cambrian stone coal deposits in northeast Hunan province. It was also one of the main controlling factors for the enrichment of trace elements in stone coal

5 T Permanent Magnetic Resonance Imaging Device and Its Application for Mouse Imaging

By improving the main magnet, gradient, and RF coils design technology, manufacturing methods, and inventing new magnetic resonance imaging (MRI) special alloy, a cost-effective and small animal specific permanent magnet-type three-dimensional magnetic resonance imager was developed. The main magnetic field strength of magnetic resonance imager with independent intellectual property rights is 1.2∼1.5 T. To demonstrate its effectiveness and validate the mouse imaging experiments in different directions, we compared the images obtained by small animal specific permanent magnet-type three-dimensional magnetic resonance imager with that obtained by using superconductor magnetic resonance imager for clinical diagnosis

Analysis of Gas Content and Permeability Change Pattern of a Coal Reservoir in the Tectonic Positions Based on a THM Coupled Model

The theory of coalbed methane distribution controlled by tectonism is a hot issue in the field of geofluid-geotectonic interaction research. Taking the geological structure in the scale range of the 1302 working face of a Guojiahe wellfield in a Yonglong mining area as the background, this paper focuses on the basic research problem of the influence of geological structure on the control of coal reservoir gas content and uses a THM coupling model to analyze the change of coalbed gas content and distribution characteristics of different tectonic positions. The change of CBM content and permeability in the anticline, syncline, and faults is analyzed. Accordingly, the variation distance of gas content and reservoir permeability controlled by tectonism of different geological structures is quantified to provide guidance for the selection of CBM-favorable areas. The research results show that the gentle dip syncline hinge zone is a potential gas-rich area with heat preservation and low permeability, while the gentle dip anticline hinge zone is a gas-poor area with low temperature and low pressure and high permeability. The thick coal seam zone of the syncline hinge zone is the potential gas accumulation zone, and the high-permeability area is near the fault plane of a normal fault. The coal matrix near the normal fault is subjected to tensile tectonic stresses to form tensional fissures, and the coal seam in the fault plane area is susceptible to coalbed gas dispersion and increases the permeability of the coal reservoir. The variation distance of gas content and reservoir permeability controlled by the normal fault within the Guojiahe wellfield is 37 m and 54 m from the fault plane, respectively

Development of the 1.2 T~1.5 T Permanent Magnetic Resonance Imaging Device and Its Application for Mouse Imaging

By improving the main magnet, gradient, and RF coils design technology, manufacturing methods, and inventing new magnetic resonance imaging (MRI) special alloy, a cost-effective and small animal specific permanent magnet-type three-dimensional magnetic resonance imager was developed. The main magnetic field strength of magnetic resonance imager with independent intellectual property rights is 1.2~1.5 T. To demonstrate its effectiveness and validate the mouse imaging experiments in different directions, we compared the images obtained by small animal specific permanent magnet-type three-dimensional magnetic resonance imager with that obtained by using superconductor magnetic resonance imager for clinical diagnosis

Basic characteristics of coalfield tectonic framework in China

The occurrence of coal-bearing strata in China is characterized by the variety of coal-bearing basins，the remarkable spatial and temporal differences of late tectonic deformations.The main controlling factors，which determine the tectonic framework of coalfields，include geodynamic environment，tectonic evolution，deep structures，tectonic stress，and lithologic combination features of coal measures.The continent of China has experienced multi-stage tectonic movements since the late Paleozoic，and due to the spatio-temporal heterogeneity of continental tectonic evolution and the complexity of basement properties，the coalfield structures present complex and ordered patterns.The coalfield tectonic framework of China can be divided into two major coalfield regions，three coal deformation zones，and five coal occurrence structural areas.Taking coal occurrence structural sub-areas as basic units，the tectonic characteristics of five coal occurrence structural areas in China were summarized in this paper

Supporting materials

Supporting materials for the details of the manuscrip