The heat of detonation of the Energetic Materials (EMs) is determined by the release of chemical energy, the bond energies, and the chemical structures, which can be reflected by the...

Online component detection is highly desirable for monitoring industrial raw materials and imported raw materials in customs. Raman spectroscopy is a possible route for in situ monitoring. However, so far, few qualitative estimations for online solid-state materials such as ore are reported due to the low accuracy of the measurements. Herein, a kind of potential online portable shifted-frequency excitation differential Raman spectroscopy (SEDRS) system was built for the first time to quantitatively determine the iron content in hematite samples with merits of no background noise and a high signal-to-noise ratio. The Raman spectra of hematite generally have strong A 1g mode at 230 and 498 cm −1 , and band intensity analysis illustrates a good positive correlation with iron content, which are used for quantitative analysis via principal component analysis and partial least squares regression. In contrast to the quantitative results based on singlefrequency excitation Raman spectra, the average relative error of the differential data treated with SEDRS was only 1.20%. The distribution of particle size for solid-state material is proven to have been the main factor for impacting the accuracy by comparing the peak intensity at 230 cm −1 of powders with different particle sizes. These findings confirm that SEDRS analysis is a high-accuracy reliable tool for analyzing iron content in hematite with uniform particle size, providing a feasible method to remotely detect the iron content of ore online.

The random lasing in quantum dot systems is in anticipation for widespread applications in biomedical therapy and image recognition, especially in random laser devices with high brightness and high monochromaticity. Herein, low-threshold, narrowband emission, and stable random lasing is realized in carbon quantum dot (CQD)/DCM nanowire composite-doped TiN nanoparticles, which are fabricated by the mixture of carbon quantum dots and self-assembly DCM dye molecules. The Förster resonance energy transfer process results in a high luminescence efficiency for the composite of carbon dots and DCM nanowires, allowing significant random lasing actions to emerge in CQD/DCM composite as TiN particles are doped that greatly enhance the emission efficiency through the plasmon resonance and random scattering. Thus, sharp and low-threshold random lasing is finally realized and even strong single-mode lasing occurs under higher pumping energy in the TiN-doped CQD/DCM composite. This work provides a promising way in high monochromaticity random laser applications.

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In general, high-accuracy quantitative analysis of material components based on Laser induced breakdown spectra requires large sample sizes for accurately modeling. However, in most cases, there are no abundant standard...