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Ultralow dispersion gradient refractive index (GRIN) microlens arrays (MLAs) covering the visible to mid-infrared wavelength range are imprinted in GeS 2 -Ga 2 S 3 -CsI chalcohalide glass by an efficient and economical microthermal poling process. The effect of poling voltage on GRIN microstructure, structural rearrangement, optical properties of the poled glasses, and imaging of the imprinted MLAs have been investigated. Optical focal length of the GRIN MLAs decreases from 353 to 63 μm with increasing the poling voltage from 200 to 1000 V, which is in accordance with imprinting-induced phase difference increase from 0.57 λ to 1.19 λ. Optimal chromatic aberration (between 520 and 850 nm) as low as 5% is achieved in the GRIN MLAs. Formation mechanism of GRIN MLAs is mainly associated with an enhanced transverse migration of Cs+ ions within mesh square area, which is provided by an improved anode of microthermal poling setup. Thus, an efficient and inexpensive process developed can produce broadband and ultralow dispersion GRIN MLAs for imaging, display, and photovoltaic applications. [ABSTRACT FROM AUTHOR]

Coal dust accumulation poses a serious risk to personnel safety. Currently, Microbially Induced Carbonate Precipitation (MICP) technology is widely employed for controlling coal dust. This study aimed to isolate a urease-producing strain, Bacillus subtilis, from a coal mining area and investigate the optimal environmental conditions affecting urease activity. The optimal conditions were found to be a urea concentration of 0.648 M, NaCl concentration of 11.899 g·L−1, and a pH value of 7.602, under these conditions, the urease activity was strongest. As evidenced by the dust suppression effect test which reduced the mass loss of coal dust samples after using biological dust suppression materials under optimal growth conditions to 0.3%. Microscope scans showed that the optimized microbial dust suppression material produced mineral particles of larger size (approximately 40 µm in diameter), with precipitation primarily in the form of calcite. The x-ray diffraction analysis showed that the optimized dust suppression material produced mineralized products with large crystal size (43.2 nm) and high crystallinity (90.3%). Additionally, molecular dynamics analysis was conducted on the Z-axis relative concentration curves of coal molecules, solution molecules, and phospholipids before and after the addition of bacteria, the analysis showed that bacteria could enhance the wettability of water to coal dust at the molecular level. Overall, the experimental data suggested that this bacteria have significant potential for suppressing coal dust. [Display omitted] • Proved that bacteria screened from coal are more adaptable to the environment. • Response surface optimization was used to illustrate the importance of medium environmental conditions for strain growth. • Verify that bacteria increase the wettability of water to coal dust at the molecular level. • A series of performance experiments show that the strain can effectively inhibit coal dust. [ABSTRACT FROM AUTHOR]