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Herein, a new template carbonization method is used to prepare calcite‐type nano‐calcium carbonate (CaCO3) with a core–shell structure using calcium hydroxide as a solute and Pluronic F‐127 as a templating and pore‐forming agent. Dopamine hydrochloride is added to control the size of calcium hydroxide particles. The morphology, particle size, and crystal type of CaCO3 are characterized via transmission electron microscopy, X‐ray diffraction, nanoparticle size, and zeta potentiometer. The creation of core–shell calcium carbonate nanoparticles is examined in relation to reaction circumstances (i.e., additive sequence, additive amount, and additive mixing time), carbonization temperature, liquid flow rate, and templates with varying chain lengths. Furthermore, a discussion is held regarding the formation mechanism of spherical core–shell calcium carbonate that is created using the innovative template carbonization method. The results show that the order, amount, liquid flow rate, and template type of additives have a significant effect on the crystal shape of calcium carbonate nanoparticles. The mixing time of additives has a significant effect on the particle size of calcium carbonate nanoparticles. Interestingly, the thickness of the shell depends on the carbonization temperature, and too slow or too fast flow rate will lead to the formation of cyclic calcium carbonate nanoparticles. [ABSTRACT FROM AUTHOR]

This study proposes a multi‐scale transformation method based on morphological reconstruction and membership filtering, termed as MMFuse, to fuse infrared and visible images. This method employs a fuzzy c‐means clustering algorithm for multi‐scale decomposition by introducing morphological reconstruction operations and modifying member partitions to ensure noise resistance and image detail preservation. In addition, the MMFuse utilises the image attributes of layers as their fusion weights at each scale for adaptive feature fusion, which reduces the difficulty of manual adjustment of fusion weights. Moreover, on the basis of histogram enhancement, a visible image enhancement method is proposed, which can help exploit additional texture details in low‐light visible images and transfer these details to the fused image. The experiments performed on public datasets indicates that the MMFuse can generate sharp and clean fused images with high robustness and good fusion results for the images corrupted by different noises. Moreover, the results of this method appear as high‐quality visible images with clear highlighted infrared targets. [ABSTRACT FROM AUTHOR]

Mountain steppe has important production value and ecological function. The chlorophyll content is a critical biochemical parameter of steppe. This study aims at exploring effective spectral parameters for estimating the chlorophyll content in mountain steppe using in situ hyperspectral measurements. The study area is located on the northern slope of Tianshan Mountains with complex terrain and sparse vegetation. The canopy hyperspectral data and leaf chlorophyll content and canopy chlorophyll content data were measured from 101 samples. The empirical models were constructed based on nine vegetation indices and three red-edge parameters. The results showed that the red-edge magnitude, red-edge area, Second Modified Chlorophyll Absorption Ratio Index, Second Modified Chlorophyll Absorption Ratio Index/Second Optimized Soil-Adjusted Vegetation Index, Second Transformed Chlorophyll Absorption Ratio Index and Triangle Vegetation Index estimated canopy chlorophyll content satisfactorily. Leaf chlorophyll content of mountain steppe is not well estimated using canopy spectral parameters. The results revealed the specific vegetation indices and red-edge parameters for estimating vegetation biochemical parameters at canopy scale in mountain steppe using in situ hyperspectral measurements. [ABSTRACT FROM AUTHOR]