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China has rich reserves of deep coal resources, and underground coal gasification can transform coal into gas and transport it to the ground, which is an important way for in-situ fluidized mining of deep coal.This article introduces the development history and technical status of underground coal gasification technology (UCG), as well as typical cases of underground coal gasification in the middle and deep parts.Based on the modern underground coal gasification technology system, the key technologies and technical research directions of deep underground coal gasification was analyzed and the prospect of deep coal gasification mining with the goal of natural gas production was outlooked.The development trend of UCG is from the mine type to the drilling type, from shallow coal seams to deep coal seams, from single power generation to comprehensive utilization.The practice of UCG in the middle and deep coal seams has verified the technical feasibility.The key technologies of deep underground coal gasification mainly include geological evaluation and scientific site selection, gasifier construction, deep coal seam high-pressure ignition, controllable mobile injection and deep fire zone geophysical detection.Deep coal gasification to produce natural gas can not only realize the clean and efficient use of deep coal resources, but also solve the contradiction between supply and demand caused by the increase in natural gas consumption.

Luminescent metal–organic frameworks (LMOFs) have been extensively employed as detection probes. However, the majority of the reported probes are fluorescence-based, lacking reports on visible afterglow detection. Herein, we present two new afterglow MOFs, compound 1 with a layered structure and 2 with an interpenetrated dia framework. 1 exhibits blue-green room temperature phosphorescence (RTP) (τ485nm = 264.6 ms) and can serve as an afterglow "turn off" probe for selective detection of Fe3+ ions through a framework decomposition mechanism, with a detection limit of 1.63 μM. Displaying blue-green RTP (τ495nm = 83.0 μs), 2 can serve as an afterglow "turn on" probe for the detection of NH3 in both solution and vapor phases. Notably, the afterglow of 2 is visually activated even at concentrations of NH3 vapor as low as 6 ppm. Mechanistic investigations reveal that the "turn on" response is attributed to structural transformation induced by NH3 molecules replacing coordinated solvents. Furthermore, their potential applications were demonstrated through the development of portable test strips for detecting Fe3+ ions and an cryptographic algorithm logic gate for NH3 deciphering. This work opens up new opportunities for the development of LMOF-based afterglow probes. [ABSTRACT FROM AUTHOR]

This paper is concerned with the inverse scattering of the rough surfaces with multi-frequency phase and phaseless measurements. We present a high-order recursive iteration method based on the homotopy iteration technique to reconstruct the rough surfaces. The convergence for the multi-frequency homotopy iteration method is obtained under some conditions. Some numerical experiments show the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Dezhou donkey is one of the representative local breeds in China, which is mainly divided into two strains: Sanfen and Wutou. There are obvious differences in coat color between the two strains. The former shows light points around the eyes, around the muzzle and under the belly, while the latter is completely solid black. In this study, genome‐wide association analysis was performed for the differences in coat color traits between the Sanfen (n = 97) and Wutou (n = 108) strains using a novel donkey 40K liquid chip developed based on GenoBaits technology, to identify genomic regions and causal genes that could explain this variation. We also used FST and The cross‐population composite likelihood ratio test (XPCLR) analyses to explore selected regions related to coat color differences. We identified one significant region on chromosome 15, with the most significant SNP located within the agouti signaling protein (ASIP) gene. At the same time, both FST and XPCLR methods detected the same selected region on chromosome 15, and ASIP was the gene with the strongest signal. ASIP and melanocortin 1 receptor (MC1R) control the ratio of eumelanin to pheomelanin through their protein activity. They are deeply involved in the process of melanosome organation and melanogenesis, thus affecting mammals' coat color variation. We used a range of genome‐wide approach to identify the genetic basis of coat color variation in Dezhou donkeys. The results provide a supplement to the color variation study in Chinese donkeys at the genome‐wide level, and preliminarily verified the reliability of the Molbreeding Donkey No. 1 40K liquid chip. [ABSTRACT FROM AUTHOR]