Analytical technology is constantly being developed, refined, and applied to different materials. A key objective is to develop technologies that are non-destructive, rapid, and improve data accuracy. Hyperspectral imaging (HSI) is a non-destructive analytical technique that measures the spectral response of molecular bonds within mineral crystals or organic matter, caused by their excitation by light. The technique has a potential to save time and money for the coal exploration and mining companies. Typically, minerals within borehole cores are characterised based on their unique spectral properties within specific infrared ranges and presented as a function of reflectance versus wavelength. to examine spectra generated on coal core samples using HSI. The HSI spectral data were compared to traditional approaches X-ray fluorescence, X-ray diffraction, proximate data, and Fourier-transform infrared spectroscopy (FTIR). A coal core from Witbank Coalfield, South Africa (Medium Rank C bituminous, inertinite-rich, generally high ash), was examined within the visible-near infrared (VNIR) (350–1000 nm) and shortwave infrared (SWIR) (1000–2500 nm) regions. The HSI coal spectra exhibit positive slopes with low reflectance values within the VNIR region and gradual increase of reflectance values in the SWIR region. The spectra are influenced by very-fine grained clay and Fe-rich minerals (pyrite and siderite) included in the coal; the latter was verified by XRD as pyrite and siderite. The spectra with higher amounts of organic matter are flat and the absorption features are weaker due to the absorbing nature of the carbon. The identified absorption features for coal functional groups within VN-SWIR are 1700 nm (CH), 2200–2206 nm (CH, CC, CO) and ∼ 2310 nm (CH), which were confirmed by FTIR data. However, the absorption features between 2200 and 2450 nm are affected by overlapping bands of inorganic phases, resulting in uncertainty. The bright banded coal (vitrinite-rich) can be adequately separated from the dull coal (inertinite-rich) through the extraction (D) of D2200 and the deepest feature between D2100 - D2450. The technique can also distinguish the carbonaceous shale from coal, demonstrating the ability to differentiate rock types based on the mineral composition and proportions.

中文翻译：

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煤岩心高光谱成像：聚焦可见光-近短波红外 (VN-SWIR) 区域

分析技术不断发展、完善并应用于不同的材料。一个关键目标是开发非破坏性、快速并提高数据准确性的技术。高光谱成像 (HSI) 是一种无损分析技术，可测量矿物晶体或有机物内分子键因光激发而产生的光谱响应。该技术有可能为煤炭勘探和采矿公司节省时间和金钱。通常，钻孔岩心内的矿物根据其在特定红外范围内的独特光谱特性进行表征，并表示为反射率与波长的函数。使用 HSI 检查煤芯样品生成的光谱。将 HSI 光谱数据与传统方法 X 射线荧光、X 射线衍射、近似数据和傅里叶变换红外光谱 (FTIR) 进行比较。来自南非 Witbank 煤田的煤芯（中等级 C 烟煤，富含惰质体，灰分普遍较高）在可见光-近红外 (VNIR) (350–1000 nm) 和短波红外 (SWIR) (1000–1000 nm) 范围内进行了检查。 2500 nm）区域。HSI 煤光谱在 VNIR 区域内呈现正斜率，反射率值较低，而在 SWIR 区域反射率值逐渐增加。光谱受到煤中含有的极细粒粘土和富铁矿物（黄铁矿和菱铁矿）的影响；后者经X射线衍射证实为黄铁矿和菱铁矿。有机物含量较高的光谱是平坦的，并且由于碳的吸收性质，吸收特征较弱。VN-SWIR 中煤官能团的识别吸收特征为 1700 nm (CH)、2200–2206 nm (CH、CC、CO) 和 ∼ 2310 nm (CH)，这些特征已由 FTIR 数据证实。然而，2200 至 2450 nm 之间的吸收特征受到无机相重叠谱带的影响，导致不确定性。通过 D2200 的提取 (D) 和 D2100 - D2450 之间的最深特征，可以将光亮带状煤（富含镜质体）与暗淡煤（富含惰质体）充分分离。该技术还可以区分碳质页岩和煤，展示了根据矿物成分和比例区分岩石类型的能力。