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By developing DPA-TPE-DCM with intense near-infrared fluorescence emission in the aggregation state, AIE materials were used for the first time in the early diagnosis of orthotopic TSCC and SLN mapping in an orthotopic TSCC-bearing mouse model.

High-density polyethylene (HDPE) pipes have been used in essential service water (ESW) systems of nuclear power plants (NPP) for years. Some NPPs use buried HDPE pipes, while some others use above ground (gallery-installed) HDPE pipes, and this paper will discuss the differences in the design methods of these two construction methods in related technical standards. The design requirements and related load types of buried and above ground HDPE pipes in safety-related Class 3 service water or cooling water piping systems are compared. Pipeline models under different load types are introduced, including model assumption, material simplification, boundary conditions, interactions, etc. The differences in design loads are summarized, i.e., soil and surcharge load, negative internal pressure, flotation due to flood of buried HDPE pipe, and axial forces due to different supporting or fixing methods of above ground HDPE pipe. The design methods of buried and above ground HDPE pipeline are discussed and compared, i.e., design of mechanical load, temperature load, non-repeated anchor movements and seismic load. A case study is presented by using different technical standards of buried and above ground HDPE pipes. This work can provide a reference for the selection of HDPE pipes for safety-related Class 3 service water or cooling water piping systems in different NPPs.

As a most feasible defect detection method, phased array ultrasonic testing (PA-UT) plays an important role in nondestructive testing of pressure vessels and piping for its high detection efficiency. It’s necessary to obtain the size and position of defects or features for safety assessment to ensure the safe running of equipment if there is a defect. However, PA-UT suffers from image distortion due to acoustic attenuation and dispersion, as well as problems with imaging principle, which usually leads to errors when measuring the size and position of detected features. In this paper, the standard polyethylene block with a through hole was tested by PA-UT and the PA-UT images of artificial defects were obtained. At the same time, the PA-UT images were simulated by combining finite element analysis of the PA-UT process as well as the ultrasonic imaging algorithm. By comparing the test results and simulation results, the influence of sector scan angle and the number of elements in the active aperture on image distortion was analyzed. Moreover, based on the simulation method, the PA-UT images were post-processed to eliminate the distortion and reconstructed to be closer to the real size. This method could be further used for improving the imaging quality of the PA-UT testing system.

Owing to the complementary high spatial resolution and signal-to-noise ratio, the dual-modality imaging technique of photoacoustic imaging (PAI)/the second near-infrared window fluorescence imaging (NIR-II FI) holds great promise for the detection of tumor tissues and sentinel lymph nodes (SLNs). Herein, by developing two aggregation-induced emission luminogens (AIEgens) (C-NTBD and O-NTBD) with benzodithiadiazole as the electron acceptor, PAI/NIR-II FI was applied to the diagnosis and treatment of neuroendocrine neoplasms (NENs) and their SLNs for the first time. Both AIEgens exhibited good PAI properties as well as intense NIR-II fluorescence emission. Among them, C-NTBD nanoparticles (NPs) have better PAI and NIR-II FI performance with maximum absorption at 732 nm and emission peak at 1042 nm. In NENs-bearing nude mice model, after successful preoperative localization of NENs by PAI, NIR-II FI was then used to detect SLNs. Under the NIR-II FI guidance of C-NTBD NPs, an SLN with a diameter of 1 mm located in the chest wall and far away from the primary tumor site was even detected and precisely removed. This dual-modality imaging technology could improve the detection of NENs and the accuracy of intraoperative SLNs dissection, improve patient prognosis, and provide a new strategy for the precise treatment of NENs.