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Small structures in coal mine working face is one of the main hidden dangers of safe and efficient production in coal mine. Currently, seismic exploration is often used as the main method for detecting such structures. However, limited by the accuracy of seismic data processing and interpretation, the interpreted location of small structures is often deviated. Ground-penetrating radar (GPR) can detect small structures accurately, but the exploration depth is shallow. The combination of the two methods can improve the exploration accuracy of small structures in coal mine. Aiming at the 1226# working face of Shuguang coal mine, we propose a method of seismic-attributes based small-structure prediction error correction using GPR data. First, we extract the coherence, curvature, and dip attributes from seismic data, that are sensitive to small structures, then by considering factors such as the effective detection range of GPR and detection environment, we select two structures from the prediction results of seismic attributes for GPR detection. Finally, based on the relationship between the positions of small structures predicted by the two methods, we use statistical methods to determine the overall offset distance and azimuth of the small structures in the entire study area and use the results as a standard for correcting each structure position. The results show that the GPR data can be used to correct the horizontal position errors of small structures predicted by seismic attribute analysis. The accuracy of the prediction results is greatly improved, with the error controlled within 5 m and reduced by more than 80%. Therefore, the feasibility of the method proposed in this study is verified. [ABSTRACT FROM AUTHOR]

An enigmatic acrochaetioid alga was collected from Niangziguan spring in Shanxi Province, northern China. Morphological data indicated that this alga reproduces exclusively asexually by monosporangia and its morphological characteristics suggested that it might be referred to Audouinella heterospora. To ascertain its phylogenetic position, phylogenetic trees were reconstructed using partial sequences of the plastid-encoded gene (rbc L) and the nuclearencoded gene (SSU rDNA) applying Bayesian inference (BI), maximum parsimony (MP) and maximum likelihood (ML). However, phylogenetic reconstructions showed that this acrochaetioid alga does not belong in a clade with the genus Audouinella, but forms a clade with Th orea hispida (Th oreales). Based on this analysis it is concluded that A. heterospora represents the 'chantransia' stage of T. hispida. [ABSTRACT FROM AUTHOR]

The combustion explosion of ordinary diesel is a global environmental problem. Green microalgae, which do not cause eutrophication, are a raw material that can be used to clean biodiesel. To increase lipid productivity, this study used a nitrogen deficient & mixotrophic (+Glucose) culture of lipid-producing microalgae Parachlorella kessleri TY from Shanxi Province, China. To examine the growth of P. kessleri TY, we measured dry weight, chlorophyll content, and chlorophyll fluorescence intensity under different culture conditions, in addition to the contents of neutral lipids, total lipids, and fatty acids, to examine its lipid accumulation ability. Cells were cultured in autotrophic, nitrogen deficient, mixotrophic (+Glucose), and nitrogen deficient & mixotrophic (+Glucose) conditions for 7 days. We found the growth of P. kessleri TY under nitrogen deficient & mixotrophic conditions was higher than that under the autotrophic and nitrogen deficient conditions, but lower than that under the mixotrophic (+Glucose) conditions. However, its lipid accumulation ability was significantly higher than that of control cultures. In conclusion, P. kessleri TY cultured under nitrogen-deficient and mixotrophic (+Glucose) conditions has significant lipid production capacity. Our results provide a theoretical basis for the use of microalgae as a raw material in the production of biodiesel, and promote the application of P. kessleri TY in large-scale production. [ABSTRACT FROM AUTHOR]