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Coal mine safety is crucial to the healthy and sustainable development of the coal industry, and coal mine flood is a major hidden danger of coal mine accidents. Therefore, the processing of coal mine water source data is of great significance to prevent mine water inrush accidents. In this experiment, the laser induced fluorescence technology was used to obtain the data information of 7 water sources with the assistance of laser. The laser emission power was set to 100 mw, and the 405 nm laser was emitted to the measured water body to obtain 210 groups of fluorescence spectral data of experimental water samples. The standard normal variable transformation (SNV) and multiple scattering correction (MSC) of the pretreatment algorithm are used to denoise the data and improve the spectral specificity. Due to the excessive calculation of the initial data, principal component analysis (PCA) was used to model and reduce the dimension of seven water samples, so as to obtain small data and maintain the data characteristics of the original information. In order to identify the water inrush type of coal mine water source, the sparrow search algorithm (SSA) is used to optimize the BP neural network in this study. This is because the SSA algorithm has the advantages of strong optimization ability and fast convergence rate compared with particle swarm optimization(PSO) and other optimization algorithms. Experiments show that under the premise of SNV pretreatment, the R 2 of SSA-BP model is infinitely close to 1, MRE is 0.0017, RMSE is 0.0001, the R 2 of PSO-BP model is 0.9995, MRE is 0.0026, RMSE is 0.0019, the R 2 of BP model is 0.9983, MRE is 0.0140, RMSE is 0.0075. Therefore, SSA-BP model is more suitable for the classification of coal mine water sources.

Cell cryopreservation is of vital significance both for transporting and storing cells before experimental/clinical use. Cryoprotectants (CPAs) are necessary additives in the preserving medium in cryopreservation, preventing cells from freeze–thaw injuries. Traditional organic solvents have been widely used in cell cryopreservation for decades. Given the obvious damage to cells due to their undesirable cytotoxicity and the burdensome post-thaw washing cycles before use, traditional CPAs are more and more likely to be replaced by modern ones with lower toxicity, less processing, and higher efficiency. As materials science thrives, nanomaterials are emerging to serve as potent vehicles for delivering nontoxic CPAs or inherent CPAs comparable to or even superior to conventional ones. This review will introduce some advanced nanomaterials (e.g., organic/inorganic nanoCPAs, nanodelivery systems) utilized for cell cryopreservation, providing broader insights into this developing field.

In this paper, a class of refinable functions is given by smoothening pseudo-splines in order to get divergence free and curl free wavelets. The regularity and stability of them are discussed. Based on that, the corresponding Riesz wavelets are constructed.

Ultrafine montmorillonite particles are the main clay minerals in industrial wastewater. In order to explore the flocculation performance and mechanism of flocculant with montmorillonite, the effects of nonionic polyacrylamide (NPAM) dosage and molecular weight on flocculation effect were studied using a flocculation sedimentation experiment. The morphology of flocs was observed by metallographic microscope and scanning electron microscope, and the microscopic adsorption mechanism was studied utilizing density functional theory (DFT). The results show that the best reagent system for the montmorillonite sample is that the molecular weight of NPAM is 14 million and the added amount is 100 g/t. The floc size increases with rising NPAM dosage, forming a unique multilevel compact space network structure through polymer bridging. The adsorption energy of acrylamide on the Na-( 001) surface of montmorillonite is -108.81 kJ/mol, which is significantly higher than -50.66 kJ/mol on the None-(001) surface. Hydrogen bonding is not the main reason for the adsorption of acrylamide on the montmorillonite surface. NPAM mainly causes the flocculation and sedimentation of montmorillonite through the processes of polymer bridging and electrostatic attraction. This study can provide a theoretical basis for the design and synthesis of new flocculants.

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