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As a kind of underwater detecting technology, hyperspectral imaging technology has been well applied in many areas. But the systems usually have a large volume, and it is hard to mount them on different platforms because the external scanning mechanisms are needed for scanning imaging. To overcome these disadvantages, an underwater hyperspectral imaging system that achieves scanning imaging through moving the objective lens is designed. The design of the optical system and internal scanning and focusing structure were completed. According to the design result, the system is assembled and tested. The imaging quality of the whole system is good, and the obtained spectrum of different targets can be distinguished. The system has a good underwater detection capability, which can provide a new feasible technical scheme for underwater detection.

Ultraviolet is an effective electromagnetic spectrum in material detection, which has wide application prospects in aerospace and environmental monitoring. A conventional imaging spectrometer has a narrow UV band and low spectral resolution. To solve this problem, a convex grating imaging spectrometer based on an Offner structure with F#2.5 and a 13 mm long slit was designed and developed. The working wavelength ranges from 200 to 433 nm, and the spectral resolution is greater than 0.5 nm. A hyperspectral data cube with both high spatial and spectral resolutions of external scenes can be obtained by the push-broom imaging mode. Fine Fraunhofer lines can be distinguished in the spectrum. The ultraviolet hyperspectral imager can be used for marine oil spills, trace gas monitoring, and other applications that require high signal-to-noise ratios, wide bands, and high spectral resolutions.

Ultraviolet (UV) hyperspectral imaging technology is commonly used in the field of atmospheric remote sensing. In recent years, some in-laboratory research has been carried out for substance detection and identification. In this paper, UV hyperspectral imaging technology is introduced into microscopy to better utilize the obvious absorption characteristics of components, such as proteins and nucleic acids in biological tissues in the ultraviolet band. A deep UV microscopic hyperspectral imager based on the Offner structure with F# 2.5, low spectral keystone and smile is designed and developed. A 0.68 numerical aperture microscope objective is designed. The spectral range of the system is from 200 nm to 430 nm; the spectral resolution is better than 0.5 nm; and the spatial resolution is better than 1.3 µm. The K562 cells can be distinguished by transmission spectrum of nucleus. The UV microscopic hyperspectral image of the unstained mouse liver slices showed similar results to the microscopic image after hematoxylin and eosin staining, which could help to simplify the pathological examination process. Both results show a great performance in spatial and spectral detecting capabilities of our instrument, which has the potential for biomedical research and diagnosis.

As a new type of pollutant, microplastics have attracted extensive attention due to its characteristics such as small size and degradation difficulty under natural circumstance. Though there are many detection methods nowadays, there are still some limitations like long detection time, high false detection rate and expensive detection equipment, which make the detection of microplastics exists in natural environment hard to carry out. To improve the environmental conditions, rapid, efficient, and accurate detection methods for microplastics are needed urgently. In this paper, a method combined the Spatial heterodyne technology and Raman spectroscopy was proposed to detect the microplastics. A spatial heterodyne spectrometer (SHS) was built, and the algorithms used to process the spectrum data were introduced. An optical system used to collect the Raman signal of the sample was built and connected with the SHS. Four different kinds of microplastic samples were detected by the complete system and identification can be achieved according to the Raman spectrum. The samples were also detected by using a normal spectrometer for comparison. A comparison of Raman spectrum using conventional dispersion spectrometer was carried out and the result shows that SHS is of higher signal-to-noise ratio. The results indicate that SHRS technology has good performance and development prospects in the field of microplastics detection.

Taking advantage of crumb rubber from waste tires to modify bitumen is widely for the environmentally friendly and sustainable development of pavement. This study investigated the modification mechanism, rheological, and aging properties of styrene–butadiene–styrene (SBS)/desulfurized crumb rubber (DCR) composite modified bitumen (SBS/DCRMB). Morphological features and chemical characteristics were assessed by fluorescence intensity measurement and gel permeation chromatography (GPC), respectively, and results demonstrated that the DCR and SBS modifier in SBS/DCRMB had been vulcanized and formed a three-dimensional network structure. Moreover, a comparison of the GPC elution curve showed the residual bitumen hardly changed due to carbon black released from DCR of SBS/DCRMB during the aging process of SBS/DCRMB, and the polymer molecules condensed to larger units. However, the remaining bitumen in SBSMB had changed evidently and the polymer degraded to smaller molecules. Meanwhile the rheological testing results, including multiple stress creep recovery, linear amplitude sweep and bending beam rheometer, declared that the SBS/DCRMB is superior to SBSMB before and after aging.

The purpose of this research was to make full use of waste lubricating by-products (LBP) and reclaimed rubber powder (RR) to modify asphalt by a one-pot approach, so as to achieve the dual purpose of solving the poor storage stability of reclaimed rubber powder modified asphalt (RRMA) and the realization of solid waste recycling. A variety of characterization techniques were performed to analyze storage stability, conventional properties and microstructure of LBP-activated reclaimed rubber powder modified asphalt (Blend). Fourier transform infrared spectroscopy illustrated that not only the chemical composition of LBP was very similar to that of asphalt, but also the activation of LBP improved the compatibility of RR with asphalt and enhanced the storage stability of Blend. Fluorescence spectrum and scanning electron microscopy results indicated that the RR without LBP activation was aggregated and dispersed as blocks in asphalt, while the LBP activated RR was uniformly dispersed in the asphalt phase. The segregation test demonstrated that Blend exhibited outstanding storage stability, in which the softening point difference was within 2.5 °C and the segregation rate was −0.2–0.2. In addition, the conventional properties of Blend have been significantly improved, especially in penetration and ductility. More importantly, the short-term aging results demonstrated that, compared with RRMA, Blend possessed excellent anti-aging performance.

Photocatalytic hydrogen generation will benefit from the realization of more active but less expensive cocatalysts compared with noble metal counterparts. Herein we developed a universal vapor deposition method that selectively uses the thermal decomposition products of sodium hypophosphite as a phosphorus source for the fabrication of inexpensive and highly efficient metal phosphate (MPi) modified CdS nanorods. We find that the modification with a bimetal phosphate (i.e., 5 wt % NiCoPi) leads to an activity enhancement by a factor of approximately 52 in boosting visible-light-driven hydrogen evolution relative to the pristine CdS nanorods. The photocatalyst exhibits a high hydrogen generation rate of 13.44 mmol·g-1·h-1, which is much higher than that of its single metal counterparts (NiPi, 8.70 mmol·g-1·h-1; CoPi, 5.79 mmol·g-1·h-1) and 1 wt % Pt modified CdS (1.33 mmol·g-1·h-1). Its apparent quantum efficiency reaches 23.5% at 420 nm. Furthermore, it also shows remarkable photostability for eight consecutive cycles of photocatalytic activity tests with total reaction time of 24 h. The excellent photocatalytic performance of the photocatalyst is believed to be associated with the in situ formed NiICoP and NiCoIIIPi cocatalysts, which not only play an important role in photogenerated charge separation but also provide highly active catalytic reaction sites for the corresponding hydrogen evolution reaction and the sacrificial agent oxidation reaction.