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During ship operations, frequent heave movements can pose significant challenges to the overall safety of the ship and completion of cargo loading. The existing heave compensation systems suffer from issues such as dead zones and control system time lags, which necessitate the development of reasonable prediction models for ship heave movements. In this paper, a novel model based on a time graph convolutional neural network algorithm and particle swarm optimization algorithm (PSO-TGCN) is proposed for the first time to predict the multipoint heave movements of ships under different sea conditions. To enhance the dataset's suitability for training and reduce interference, various filter algorithms are employed to optimize the dataset. The training process utilizes simulated heave data under different sea conditions and measured heave data from multiple points. The results show that the PSO-TGCN model predicts the ship swaying motion in different sea states after 2 s with 84.7% accuracy, while predicting the swaying motion in three different positions. By performing a comparative study, it was also found that the present method achieves better performance that other popular methods. This model can provide technical support for intelligent ship control, improve the control accuracy of intelligent ships, and promote the development of intelligent ships. [ABSTRACT FROM AUTHOR]

The sialidases, which catalyze the hydrolysis of sialic acid from extracellular glycoconjugates, are a group of major virulence factors in various pathogenic bacteria. In Porphyromonas gingivalis, which causes human periodontal disease, sialidase contributes to bacterial pathogenesis via promoting the formation of biofilms and capsules, reducing the ability for macrophage clearance, and providing nutrients for bacterial colonization. Here, the crystal structure of the P. gingivalis sialidase SiaPG is reported at 2.1 Å resolution, revealing an N‐terminal carbohydrate‐binding domain followed by a canonical C‐terminal catalytic domain. Simulation of the product sialic acid in the active‐site pocket together with functional analysis enables clear identification of the key residues that are required for substrate binding and catalysis. Moreover, structural comparison with other sialidases reveals distinct features of the active‐site pocket which might confer substrate specificity. These findings provide the structural basis for the further design and optimization of effective inhibitors to target SiaPG to fight against P. gingivalis‐derived oral diseases. [ABSTRACT FROM AUTHOR]

Abstract: The reaction mechanism of 3-chlorophenol with OH, H in aqueous solution was studied by transient technology. The 3-chlorophenol aqueous solutions have been saturated with air or N[sub 2] previously. Under alkaline condition, the reaction of OH radical with 3-chlorophenol produces 3-chlorinated phenoxyl radical, with the absorption peaks at 400 nm and 417 nm. Under neutral condition, the reaction of OH radical with 3-chlorophenol produces OH-adduct with the maximal absorption at about 340 nm. And in acid solution, the reaction of H with 3-chlorophenol produces H-adduct with the maximal absorption at about 320 nm. 3-chlorophenol is compared with 4- and 2-chlorophenols from the free radical pathways. The results show that the positions of chlorine on the aromatic ring strongly influence the dehalogenation and degradation process. [ABSTRACT FROM AUTHOR]

Abstract: The photolysis of simulating low concentration of hydrogen sulfide malodorous gas was studied under UV irradiation emitted by self-made microwave discharge electrodeless lamps (i.e. microwave UV electrodeless mercury lamp (185/253.7nm) and iodine lamp (178.3/180.1/183/184.4/187.6/206.2nm)). Experiments results showed that the removal efficiency () of hydrogen sulfide was decreased with increasing initial H2S concentration and increased slightly with gas residence time; H2S removal efficiency was decreased dramatically with enlarged pipe diameter. Under the experimental conditions with pipe diameter of 36mm, gas flow rate of 0.42standardls−1, was 52% with initial H2S concentration of 19.5mgm−3 by microwave mercury lamp, the absolute removal amount (ARA) was 4.30μgs−1, and energy yield (EY) was 77.3mgkWh−1; was 56% with initial H2S concentration of 18.9mgm−3 by microwave iodine lamp, the ARA was 4.48μgs−1, and the EY was 80.5mg kWh−1. The main photolysis product was confirmed to be with IC. [Copyright &y& Elsevier]

The 355nm photon-initiated microscopic reaction mechanisms of the mixed aqueous solution of nitrobenzene and nitrous acid in the presence or absence of O2 were studied by the laser flash photolysis technique. The main transient absorption peaks in the recorded spectra were assigned and the growth/decay trends of several transient species were investigated. It was found that the OH radical formed from the photolysis of nitrous acid triggered most of the subsequent radical reactions. The rate constant of the reaction between OH radical and nitrobenzene was measured to be (3. 4±0. 1)×109 lmol−1 s−1. The product from this reaction, namely C6H5NO2–OH adduct, was found to react with O2 to yield C6H5NO2–OHO2 adduct with a rate constant of (1. 6±0. 2)×109 lmol−1 s−1. Final steady-state products were identified by GC/MS analysis and were in accordance with the transient spectroscopic results. The possible reaction pathways were proposed. [Copyright &y& Elsevier]

The photolysis of simulating low concentration of hydrogen sulfide malodorous gas was studied under UV irradiation emitted by self-made microwave discharge electrodeless lamps (i.e. microwave UV electrodeless mercury lamp (185/253.7 nm) and iodine lamp (178.3/180.1/183/184.4/187.6/206.2 nm)). Experiments results showed that the removal efficiency (eta H2S) of hydrogen sulfide was decreased with increasing initial H2S concentration and increased slightly with gas residence time; H2S removal efficiency was decreased dramatically with enlarged pipe diameter. Under the experimental conditions with pipe diameter of 36 mm, gas flow rate of 0.42 standard l s(-1), eta H2S was 52% with initial H2S concentration of 19.5 mg m(-3) by microwave mercury lamp, the absolute removal amount (ARA) was 4.30 microg s(-1), and energy yield (EY) was 77.3 mg kW h(-1); eta H2S was 56% with initial H2S concentration of 18.9 mg m(-3) by microwave iodine lamp, the ARA was 4.48 microg s(-1), and the EY was 80.5mg kW h(-1). The main photolysis product was confirmed to be SO4(2-) with IC.

The rate constants of reactions between the SO4*(-) radical and some common anions in atmospheric aqueous droplets e.g. Cl-, NO3-, HSO3- and HCO3- were determined using the laser flash photolysis technique. Absorption spectra of SO4*(-) and the product radicals were also reported. The chloride ion was evaluated among all the anions to be the most efficient scavenger of SO4*(-). The results may supply useful information for a better understanding of the vigorous radical-initiated reactions in atmospheric aqueous droplets such as clouds, rains or fogs.