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In order to simply, quickly and efficiently evaluate the impact of nuclear power plant operation on the surrounding marine environment, a cobalt sulfide coprecipitation method was established to rapidly analyze the gross beta activity excluding 40K in seawater. The effects of constant temperature, initial pH value of solution and constant temperature time on the enrichment rate of Ag, Fe, CO and Sb in the analysis of gross beta activity excluding 40K in seawater by cobalt sulfide coprecipitation method were studied. It is determined that the pH value of the supernatant after cooling is the key factor affecting the enrichment rate of radionuclides. The detection efficiency of 60Co and 137Cs on the proportional counter was studied, and 60Co is recommended as the calibration source for the efficiency calibration of this method. The detection limit is 0�005 7 Bq/L for 3�0 L seawater samples. The analysis results of gross beta activity excluding 40K in actual seawater show that the range is 0�083�0�113 Bq/L. The spiked experimental results show that the maximum relative deviation between the measured value and the spiked value is -8�33%, which confirms the accuracy of this method.

Clozapine (CLZ) is the most prescribed medication for treating refractory schizophrenia but is associated with significant cardiovascular toxicity. This study aimed to investigate the cardiovascular toxicity induced by CLZ using zebrafish as a model animal. For this purpose, zebrafish developed to 80‐h post‐fertilization were exposed to different CLZ concentration solutions for 24 h followed by cardiac morphological observations in yolk sac edema, pericardial edema, and blood coagulation, in addition to increased SV‐BA distance, functionally manifested as bradycardia, and decreased cardiac ejection fraction using the untreated embryos as control. At the same time, RNA sequencing was used to study the possible molecular mechanism of CLZ‐induced cardiovascular toxicity. The results indicated that compared to the control group, the experimental groups possessed a total of 5888 differentially expressed genes (DEGs), where gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment of analysis indicated that DEGs were mainly enriched in the pathways related to ion channels. These findings may provide new insights and directions for the subsequent in‐depth study of the molecular mechanism of CLZ‐induced cardiovascular toxicity. Zebrafish embryos showed varying degrees of morphological and functional changes; RNA sequencing revealed 5888 differentially expressed genes compared to the control group. GO and KEGG enrichment analysis revealed multiple potentially related ion channel genes were involved; the top 6 pathways included the mismatch repair, primary bile acid biosynthesis, NOD‐like receptor, cell adhesion molecules, butanoate metabolism, and calcium signaling pathways. [ABSTRACT FROM AUTHOR]

Precise damage identification and quantification is of great significance to ensure structural performance and provide early-warning for safety maintenance. In this research, a time-reversal assisted probabilistic strategy is developed to accurately localize damage via baseline-free manner in plate-like structures by fusing damage prediction data obtained from the elliptical trajectory location method (ETLM) and reconstruction algorithm for probabilistic inspection of defects (RAPID) algorithm. Damage features, including time difference for ETLM and correlation coefficient index (CCI) for RAPID algorithm, are extracted from the time-reversal focusing signal using the Hilbert transform (HT). To make full use of the damage-related information contained in the time-reversal focusing signals and improve the localizing accuracy, a decision-level data fusion based on Bayesian inference is proposed to fuse damage features and reconstruct damage information. A series of numerical and experimental studies, including different configurations of damage cases and transducer distributions, were conducted to investigate the performances of the proposed time-reversal assisted probabilistic method on damage localization. Results shows that the proposed method could successfully achieve accurate damage localization via baseline-free manner and significantly reduce the damage artifacts compared to traditional methods. [ABSTRACT FROM AUTHOR]

In this study, an implantable array-based sensing technique for damage imaging of concrete wall-like structures was developed. Unlike conventional concrete damage imaging methods that require several distributive transducers instrumented in the detection structure, the proposed technique integrates a multi-transducer into a cylindrical concrete implantable module (CCIM) that can be directly implanted into the wall-like structures to transmit and receive probe signals based on a sensing array. Implantable designs within integrated sensing elements benefit the management of devices and provide a new transducer-to-structure installation for structural health monitoring (SHM). Furthermore, to analyze the received probe signals and visualize the structural defects, a novel damage-imaging algorithm aimed at a heterogeneous concrete medium was proposed. The algorithm assumed that each point in the detection space was a virtual scatter to simulate a series of signal transceiving processes using a computer. The virtual scattered signals received by the CCIM were projected onto the signals received under real damage conditions to reconstruct an imaging map. The reliability of the developed technique for damage imaging of heterogeneous concrete wall-like structures was studied both numerically and experimentally. The numerical study employed a 2-D mesoscale model considering concrete as a multiphase composite material and revealed the stress-wave propagation law in concrete. In the experiment, two fabricated CCIMs were implanted into a concrete wall-like specimen for signal transmission and reception. The imaging results acquired by simulation and experiment both successfully displayed the damaged area and exhibited excellent prospects for the implantable array-based sensing technique in SHM. [ABSTRACT FROM AUTHOR]