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As a mesh-free approach, the incompressible Smoothed Particle Hydrodynamics (ISPH) method has been often used for simulating wave-structure interaction problems. In the conventional ISPH method, the pressure-projection phase of solving the pressure Poisson's equation (PPE) is the most time-consuming. In recent years, the machine learning (ML) techniques has gradually shown their potential in accelerating the computational fluid dynamics. In this paper, the graph neural network (GNN) supported ISPH method (ISPH_GNN), in which the GNN replaces solving the PPE for the fluid pressure in the conventional ISPH, is adopted for numerical simulations of wave-floater interactions. To the best of the authors' knowledge, this is the first work to study the wave-floater interactions by using GNN supported ISPH method. More importantly, this paper demonstrates that the GNN trained only on data for simpler wave-only cases (i.e. no structure in the wave fields) can be satisfactorily applied to the cases for wave-floater interactions. More specifically, the paper will show this by using the ISPH_GNN with such trained GNN model to simulate various different cases, including the decay tests of a box, a floating box subjected to a wave, the interaction between wave and a moored floating breakwater and the violent green water impact on a floating structure. In most of the cases, the numerical results are validated by comparing with experimental data. Agreement between them is surprisingly satisfactory, being as good as those obtained by the conventional ISPH. The paper will also show that the ISPH_GNN requires much less computational time (97 times less for the cases concerned) than the conventional ISPH for estimating pressure involved in wave-floater interactions. This reveals a great potential that one can train the GNN using the datasets for simpler cases and then use the ISPH_GNN to simulate wave-floater interaction problems. • The first work to study the wave-floater interactions by using the graph neural network (GNN) supported ISPH method. • The GNN trained only on data for simpler wave-only cases can be applied to more complex cases for wave-floater interactions. • The ISPH_GNN can give satisfactory results for the relatively complex cases involving wave-floater interactions. • The ISPH_GNN takes much less computation time than the conventional ISPH for estimating pressure. [ABSTRACT FROM AUTHOR]

Following the development of offshore wind turbine (OWT) systems and wave energy converters (WECs), there is an increasing demand for the development of hybrid systems that combine OWTs with WECs, for the purpose of reducing the Levelized Cost of Electricity (LCOE) of WECs by sharing foundations, increasing overall power output, and optimizing the utilization of marine space. One of the hybrid systems integrates WECs with the most widely adopted foundation used by existing wind farms, i.e. the fixed monopile foundation. While existing research mainly focuses on the characteristics of loads and power performance of WECs, the corresponding characteristics related to wave load on the monopile foundation and the hybrid system play a critical role in securing the safety and stability of the monopile foundation but is limited in the available literature. This paper presents an analysis of wave load characteristics on a fixed monopile foundation of a 15 MW OWT integrated with a torus-shaped heaving WEC using the ANASYS-Aqwa adopting the linear potential theory. The structure is subjected to regular and irregular waves in the operational sea conditions. The power take-off (PTO) system of the WEC is modelled by applying a linear damping in the present numerical work. The results suggest that the PTO damping has an insignificant impact on the wave load statistics. It is further confirmed that, the integrated WEC effectively reduces the wave load and overturning moment acting on the monopile foundation within a wide range of wave conditions. Moreover, the presence of the monopile also reduces the horizontal wave load on the WEC. However, the overall load on the hybrid system, which is the resultant force of horizontal wave force acting on buoy and monopile, is higher than that experienced by the monopile foundation of the OWT prototype. To the best of our knowledge, this is the first work investigating into the effect of integrated torus-shaped WECs on wave loads affecting fixed foundations. The findings offer valuable insights for the design and deployment of such hybrid systems in the near future. • Wave load characteristics on the monopile foundation and hybrid system are systematically studied. • Wave load characteristics in the operational sea are analyzed considering the effects of the PTO system on the buoy. • The coupled buoy mainly provides a shielding effect and reduces the diffraction wave force on the monopile. • The overall load on system is higher with considering the introduced buoy within the range of consideration of this paper. [ABSTRACT FROM AUTHOR]

Hybrid wind-wave systems combining the wave energy converters (WECs) with offshore wind turbines (OWTs) is a promising way to enhance the power production and improve the sea space utilization. In this paper, a novel hybrid wind-wave conceptual system, in which a multi-buoy WEC is integrated with a fixed monopile OWT, is proposed. This is the first concept utilizing multi-buoy WECs and is distinguished from existing hybrid wind-wave systems with a fixed monopile OWT, which integrate a single oscillating water column or a heaving point absorber. To characterize the hydrodynamics associated with the proposed system in operational wave conditions with different directionalities, a potential flow solver with an appropriate power take-off (PTO) model is applied. The results demonstrate a significant buoy-buoy and buoy-monopile hydrodynamic interaction, suggesting that the existing hydrodynamic characteristics for the wind-wave system with a single buoy WEC may not be applicable to the new system. More importantly, the power performance of the present system is proven to be better than the corresponding single-buoy wind-wave system, as being quantitatively assessed by the newly-defined evaluation index within the range of the consideration of this paper. [ABSTRACT FROM AUTHOR]

Starting from readily available vanillin and α-D-acetobromo glucose, two natural acylated phenolic glycosides vitexnegheteroin A and ovatoside D were synthesized for the first time in 4 steps with overall yields of 54% and 65%, respectively. The key steps involve the directly regioselective O -6 acylation of vanillin β-D-glucopyranoside with acyl chlorides, and simultaneous removal of the allyl protecting groups on the phenolic acid moiety and reduction of the aldehyde in the aglycon moiety by using Pd(PPh) 3 -NaBH 4 system in one pot. [ABSTRACT FROM AUTHOR]

As a popular method for modeling violent free surface flow, the incompressible Smoothed Particle Hydrodynamics (ISPH) based on the Lagrangian formulation has attracted a great attention worldwide. The Lagrangian ISPH solves the unsteady Navier-Stokes and continuity equations using the projection method, in which the pressure is obtained by solving the pressure Poisson's equation (PPE) that is the most time-consuming part in the ISPH procedure. In this paper, the Convolutional Neural Network (CNN) is combined with ISPH and used to predict the fluid pressure instead of solving the PPE directly. Although limited attempts of using CNN for solving the PPE in Eulerian formulation (referred to as the Eulerian CNN framework) in mesh-based methods are found in the public domain, the present model is the first ISPH model supported by CNN in a Lagrangian formulation. The proposed model overcome several challenges associated with combining CNN with ISPH, including selecting the input parameters, formulating the objective functions, producing the training dataset and dealing with boundary conditions. Two classic free surface problems, i.e. the dam breaking and the wave propagation, are simulated to evaluate the performance of the present model. Quantitative assessments of the numerical error in terms of both the free surface profile and the pressure field are carried out. The assessments show that the new model does not only give results with satisfactory accuracy, but also requires much less computation time for estimating pressure if the number of particles is large, e.g., 100 thousands particles that is usually required in the practical ISPH simulation for free surface flow. [ABSTRACT FROM AUTHOR]

Abstract: An efficient, chemoselective, and environment-friendly method for the deprotection of tert-butyldiphenylsilyl ethers mediated by triflic acid supported on silica gel is reported. A wide range of tert-butyldiphenylsilyl ethers derived from carbohydrate and saponin residues can be smoothly cleaved in the presence of various types of other protecting groups in good to excellent yields in acetonitrile. This heterogeneous reaction does not require aqueous workup, and the supported catalyst can be readily recycled. [Copyright &y& Elsevier]

The incompressible Smoothed Particle Hydrodynamics (ISPH) is one of the most popular Lagrangian particle methods for modelling wave-structure interactions. It solves the unsteady Navier-Stokes and continuity equations using the projection method, in which solving the pressure Poisson's equation (PPE) plays a critical role. To discretise the Laplacian operator, the quadric semi-analytical finite difference interpolation scheme (QSFDI) has been developed recently and the relevant patch test has demonstrated its superiority over existing schemes at a similar accuracy level in terms of the convergence and robustness. In this paper, the QSFDI is adopted by the ISPH for discretising the Laplacian operator in the PPE. The developed scheme (ISPH_QSFDI) is then applied to various cases with wave propagations and wave impacts on structures. For the purpose of comparison, other Laplacian discretisation schemes, including the classic scheme widely adopted by the ISPH, the CSPM and the CSPH2Γ, have also been considered. Except the Laplacian discretisation, other numerical implementations of the ISPH are kept the same as the classic ISPH. The convergence, accuracy and robustness of these schemes are analysed with reference to either analytical solutions or experimental data. The results demonstrate that the present ISPH_QSFDI leads to more accurate results with the same number of particles and costs less computational time to achieve a specific accuracy, compared with other schemes, although the convergence rate of the ISPH_QSFDI seems to be one-order lower than the theoretical patch test primarily due to the fact that linear schemes are used for the discretisation of the right-hand side of the PPE, the gradient/divergence estimation and the treatment of the boundary conditions. [ABSTRACT FROM AUTHOR]

Abstract: An efficient synthesis of 4-methoxyphenyl α-l-Rhap-(1→3)-α-l-Rhap-(1→3)-α-l-Rhap-(1→2)-6-deoxy-α-l-Talp, the tetrasaccharide related to the GPLs of Mycobacterium intracellare serotype 7, was achieved with 4-methoxyphenyl 3,4-di-O-benzoyl-6-deoxy-α-l-talopyranoside (6c) as the key intermediate which was obtained through selective 3-O-benzoylation of 4-O-benzoyl-6-deoxy-α-l-taloside. Coupling of 6c with 3-O-allyloxycarbonyl-2,4-di-O-benzoyl-α-l-rhamnopyranosyl trichloroacetimidate followed by removal of the allyloxycarbonyl protecting group afforded the disaccharide acceptor 11. Condensation of 11 with 2,3,4-tri-O-benzoyl-α-l-rhamnopyranosyl-(1→3)-2,4-di-O-benzoyl-α-l-rhamnopyranosyl trichloroacetimidate and subsequent deprotection gave the target tetrasaccharide. [Copyright &y& Elsevier]

Abstract: 1-O-Allyloxycarbonyl (or ethyloxycarbonyl)-2-azido-2-deoxy-3-O-benzyl (or allyl, or benzoyl)-4,6-O-isopropylidene-β-d-mannopyranose derivatives were prepared from the corresponding 2-hydroxy-β-d-glucopyranosyl carbonates in high yields via triflation of the 2-hydroxyl group and subsequent SN2 displacement with azide ion. An N-acetyl-mannosamine-containing trisaccharide, a fragment of the putative O10 antigen from Acinetobacter baumannii, was efficiently synthesized using these derivatives. [Copyright &y& Elsevier]

Trimaran added resistance and seakeeping performance in oblique waves with strong nonlinearity are rarely investigated. This paper presents the numerical investigations on them by applying a hybrid method, called the QaleFOAM. This method can simulate a trimaran moving in a large wave field, considering viscous effects and dealing with violent wave-structure interaction (WSI). The numerical method is validated by experimental data for a trimaran moving in waves. Various cases are investigated with different wave steepness, different wavelengths, different forward speeds and different wave incident angles to study the properties and characteristics of the added resistance and seakeeping performance of a trimaran. The results demonstrate that the variational trend of the added resistance and motion amplitudes of the trimaran in waves is significantly affected by the wave steepness and wave incident angles and different from those of traditional mono-hull ships. • A systematic study on the added resistance/seakeeping performance of trimarans in oblique waves of different parameters. • Directly modelling the advancing of the trimaran in waves by using a robust hybrid model, QaleFOAM. • The added resistance and motion amplitudes of the trimaran are significantly affected by the wave steepness and wave incident angles. • Two approaches (directly modelling or inputting ship speed and waves at inlet) for forward ship in waves leading to considerable difference. [ABSTRACT FROM AUTHOR]

Abstract: A new and efficient method for the preparation of 1,6-anhydro sugars using silica supported perchloric acid as a catalyst is described. The catalyst is heterogeneous and 1,6-anhydro sugars could be formed within a few minutes with good yields. [Copyright &y& Elsevier]

To assess the survivability of marine structures, numerical tools that can predict the interaction between extreme waves and structures are needed. Considering the significant nonlinearity associated with the problem, fully nonlinear models, including the fully nonlinear potential theory (FNPT) and general viscous flow theory based on the Navier-Stokes equation (NS) and Continuity equation, are necessary for a reliable prediction. Both methods have relatively higher computational cost compared to the linear or second order wave theories, which are popular in routine design practices. Although the FNPT model generally requires less computational efforts compared to the NS model, its theoretical assumption, i.e. the flow is incompressible, irrotational and inviscid, invalidates its applications to those problems with significant viscous effects and/or breaking waves. It is, therefore, necessary to conduct a comparative study on the accuracy of the FNPT in various problems to quantify its range of application. In this paper, both the Quasi Arbitrary Lagrangian Eulerian Finite Element (QALE-FEM) method based on the FNPT model and the open source Reynolds Average Navier-Stoke (RANS) based code, OpenFOAM, are used to predict the interaction between extreme waves and a moored Floating Production Storage and Offloading (FPSO) model. The extreme waves are generated using the NewWave theory and different wave steepnesses are used. The results, including the wave runup, pressure and force on the FPSO, are compared with the corresponding experimental data obtained from the ocean basin at the COAST Laboratory, University of Plymouth. Satisfactory agreement between the numerical predictions and the experimental measurements are observed. It is also concluded that the differences between the QALE-FEM results and the OpenFOAM results are mainly caused by the effectiveness of the wave generation in the corresponding simulations; the viscous effects may be considerable in the rotational motion of the FPSO when subjected to extreme waves. • A numerical comparative study on extreme wave interaction with moored FPSO using FNPT (QALE-FEM) and CFD solvers (OpenFOAM). • New sets of experimental data for interaction between extreme waves and a moored FPSO. • Investigations on the viscous effects associated with the FPSO in extreme wave conditions. • Effect of the wave generation on overall accuracy of wave runup and motion responses of the floating structures. [ABSTRACT FROM AUTHOR]

• The total synthesis of leontopodioside A was achieved by two strategies for the first time. • Glycosylation of chalcone acceptor first followed by the cyclization to construct the flavone scaffold. • The strategy has general applicability for the synthesis of other flavonoid glycosides. Leontopodioside A, isolated from the whole plants of Leontopodium leontopodioides , possesses significant α -glucosidase inhibitory activity. In this work, we studied the total synthesis of leontopodioside A by two strategies for the first time. The optimized strategy involved nine linear steps and has an overall yield of 16.1%. The key feature of the strategy is that glycosylation of chalcone acceptor first followed by the cyclization to construct the flavone scaffold, which has general applicability for the synthesis of flavonoid glycosides. [ABSTRACT FROM AUTHOR]

Natural flavonoids and flavonoid glycosides exist in many plants and have been demonstrated to possess various clinically relevant properties, isolating large amounts of these compounds that have striking structural similarity from plant sources needs tedious isolation techniques. These processes limited their availability in structural diversity for structure−activity relationship (SAR) studies, and restrict large quantities for, as an example, their mechanistic evaluation of the in vivo activities. In this work, we developed a semi-synthetic strategy from scutellarin for the synthesis of a series of natural flavonoids and flavonoid glycosides. By taking this strategy, eight bioactive flavonoids with striking structural similarities were synthesized efficiently and practically. The sufficient amounts obtained products will greatly facilitate the SAR studies and mechanistic evaluation of the in vivo activities. Image 1 • Semi-synthesis of natural flavonoids and flavonoidglycosides from scutellarin. • Eight bioactive flavonoids with striking structural similarities were synthesized. • The syntheses of linaroside, stachannin A and homoplantagininwere reported for the first time. [ABSTRACT FROM AUTHOR]

This paper numerically investigates the energy evolution of the focused wave and its correlation with input parameters for the wave generation. The focused wave is numerically generated based on the fully nonlinear potential wave theory which is solved by the Quasi Arbitrary Lagrangian Eulerian-Finite Element Method. The investigation is performed by dividing the generated wave energy into three categories according to their frequency intervals, i.e., the initially assigned frequency interval [ f 1 f N ] , the frequencies lower (f < f 1) and higher (f > f N) than the initial interval. The amount of the generated energy falling into three energy categories and the energy distribution in the initial frequency interval are analysed against amplitude parameters and frequency bands under three amplitude spectra. Four indicators are proposed to indicate the actual energy variations comparing to the initial design. It is found that for all the three frequency intervals the energies increase when the amplitude parameters increases or the given frequency shifts towards the lower frequency domain. The choice of wave amplitude spectrum plays a significant role to maintain the distribution of the energy in the design frequency range and to minimise the energies out of the design frequency range. The results from the second-order wave group theory are used to assist analyses of the mechanism of the energy evolution alongside the focused wave generation. It is found that the lower-frequency energy in the vicinity of the focusing point is dominated by the second-order difference waves, whereas the higher-frequency energy is mainly produced by the wave flap. The waves which are higher than the second-order and the complex interactions not considered by the second-order wave theory are found significantly disturbing the energy distribution in the originally assigned wave-frequency interval. [ABSTRACT FROM AUTHOR]

A fast and accurate prediction of the wake of an upwind turbine is very important to quantify the performance of downwind turbines in offshore wind farms, which become larger and larger. The wake flow and dynamics may be quite accurately simulated by high-fidelity computational fluid dynamics (CFD) software but its computational costs are too high, in particular to simulate a long wake flow often required in engineering practice. Therefore, the wake is often modelled by simplified dynamic wake models in design practices. They are computationally efficient but could not catch all physics, depend on pre-specified empirical parameters, and are not suitable for flow near the turbine. This paper proposes a new hybrid method, in which the near wake flow is simulated by a CFD model based on Navier–Stokes equations with the turbine represented by actuator lines while the far wake flow is modelled by an improved simplified CFD-based dynamic wake model. The two models are two-way coupled at a section downwind the turbine. The newly formulated method is validated by the results of full CFD simulations in the whole domain. Its performances are investigated under different conditions. It will be demonstrated that the new method takes considerably less computational time than the full CFD tool to produce similar results. • Develop and present a new hybrid method for modelling the wake dynamic of wind turbines. • Propose an improved dynamic wake model and use it in the hybrid method. • Validate the new method and new dynamic wake model. [ABSTRACT FROM AUTHOR]

The Korteweg–de Vries (KdV) equation is often adopted to simulate phase-resolved random waves on large scale in shallow water. It shows that the KdV equation is computationally efficient and can give sufficiently accurate results, but it is not always suitable and the error by using it cannot be predicted. This paper attempts to give the quantitative formulas for estimating the error of the statistics when simulating random waves in shallow water by using it. The formulas are obtained by fitting the errors of the KdV equation in comparison with the fully nonlinear model using the same initial condition based on the Wallops spectrum with a wide range of parameters. This paper also demonstrates how the formulas would be used, e.g., to estimate the error of the results by using the KdV model, or to justify its suitability for modelling random waves on large scale in shallow water. [ABSTRACT FROM AUTHOR]

Focusing waves are often considered as an effective simulation of freak waves observed in oceans, or extreme sea states for marine structures design. The understanding of factors in generating prescribed focusing wave is of great importance for its generation in both numerical and physical wave tank. Based on the fully nonlinear potential theory solved by the QALE-FEM, this paper numerically investigates the effect of wave amplitude distribution over the frequency band under a series of the crest elevation parameters and frequency ranges on focusing wave generation, including focusing wave crest elevations and focusing positions. The results suggest that focusing wave crest elevation is significantly affected by the wave amplitude distribution especially for target waves with large wave crests or those are assigned at low frequency domain. Moreover, generation positions of focusing wave are also strongly correlated to amplitude spectra through phase shift of the wave surface and wave nonlinearity denoted by wave steepness. • Results for guiding amplitude spectra type selection to generate tailored focusing waves in physical or numerical wave tank. • Three amplitude distributions of wave components over frequency band are numerically tested to generate focusing waves. • Wave amplitude spectra affects focusing wave profiles. • Large amplitudes at low end of the frequency band produce the highest focusing wave crest and the nearest focusing position. • Wave amplitude spectra significantly affect the focusing position through wave surface phase shift and nonlinearity. [ABSTRACT FROM AUTHOR]

As one of the widely used high-performance ships, the hydrodynamic characteristics of the trimaran ships have been widely investigated in recent years. But, the study on the maneuverability and the skill of the maneuvering simulation are still limited. In this paper, a hybrid method coupling the FNPT-based (fully nonlinear potential flow theory) QALE-FEM (quasi arbitrary Lagrangian-Eulerian finite element method) with the viscous flow method is applied to simulate the turn and zigzag maneuvers of the trimaran in both calm water and waves. The environment of calm water and incident waves is simulated by the numerical tank of QALE-FEM. The maneuvering of the trimaran is carried out in the scope of the numerical tank by the viscous flow method. The grid convergence test is carried out first, and the computed results are compared with the experimental results. Then, the turn and zigzag maneuvers of a trimaran model in both calm water and waves are simulated to study the trimaran's maneuvering characteristics. 1) A hybrid method coupling the FNPT-based QALE-FEM and viscous flow theory is applied to simulate turn and zigzag maneuvers of a trimaran in both calm water and head waves. An external domain by FNPT-based QALE-FEM is used to simulate a numerical tank. An internal domain by viscous flow method is used to simulate the maneuvering of the trimaran, which could take the nonlinear effect into accounts, such as green water and side-hull intermittent emergence. 2) The turn and zigzag maneuvers in calm water and waves are simulated, and the effect of the speed on the turn and zigzag maneuvers are analyzed. 3) By numerical simulation of trimaran's maneuver in waves, the effect of wavelength and wave steepness on the maneuverability of the trimaran was studied. [ABSTRACT FROM AUTHOR]

This work uses machine learning to produce synthetic data of wave energy converters from time-expensive 3D simulations based on computational fluid dynamics models. The simulations to analyse the response of these systems to incoming waves are lengthy and computationally expensive to obtain. Here, we explore the use of a beta-VAE and a Principal Components-based adversarial autoencoder for generating new synthetic data. The compression plus the generation of synthetic data introduces an exceptionally fast surrogate model of the original simulation and delivers more samples of either dynamic viscosity and velocity fields, enlarging the design space. The new generated synthetic samples can have a speed up from 5 to 6 orders of magnitude. The new design space can be used to improve the prediction of dynamic viscosity given the velocity fields. The generative model has the potential to capture the transition and the new physical phenomena under extreme initial conditions. • We propose a surrogate model for Wave Energy Converters Computational Fluid Dynamics. • Generative models are used to create unseen scenarios of velocity and dynamic viscosity responses. • Two different generative models are employed and expand the design space. • These generative models can produce 100 new scenarios in up to 10 s. • To create high-fidelity scenarios, it is better to separate all variables and preprocess them individually. [ABSTRACT FROM AUTHOR]

• The phase-resolved fully nonlinear numerical simulations of directional seas with presence of opposing and oblique current on large spatiotemporal scale are carried out. • This study reports some new findings about how the fully nonlinear wave-current interactions modify the extreme wave properties in directional seas subject to current from different incident angles. • The study also discusses whether the NewWave model is sufficient for describing the average shape of extreme waves induced by fully nonlinear wave-current interactions in directional seas. This paper will address two questions: i) How the fully nonlinear wave-current interactions modify the extreme wave statistics, spectrum characteristics and average shape of extreme waves in directional seas subject to current with different incident angles; ii) Whether the NewWave model is adequate to describe the average shape of nonlinear extreme waves in directional seas with presence of opposing and oblique current. This study employs fully nonlinear numerical simulations, and the results demonstrate that current can enhance the wave crest exceedance probability at distribution tail and kurtosis, broaden the spectra, and cause severe vertical and horizontal asymmetry of extreme wave profiles depending on the incident angle and initial wave steepness. The assessment on the NewWave models reveals that they fail to predict the reduction of the crest width with increasing current incident angle and significantly underestimate the asymmetry parameters for large steepness waves. [ABSTRACT FROM AUTHOR]

Abstract In order to gain advanced understanding of the mechanism of the submerged oil leakage from damaged tankers subjected to wave-excited motions, a three-dimensional (3D) full scale numerical model is developed in this paper. The model is based on the three-phase Navier-Stokes equation and the continuity equation, which are solved by using the finite volume method (FVM). The volume of fluid (VOF) method is implemented to identify the interfaces between different phases and the k-ε turbulence model is employed to approximate the turbulence effects. The prototype of the oil tanker is taken as the side tank of VLCC, which is subjected to a periodically forced motions yielding a liquid sloshing inside the tank. After being validated by comparing its prediction with experimental data, the present model is utilized to a systematic investigation with wide range of applications including different motion amplitudes and periods. The dynamic characteristics of both the macroscopic parameters, e.g. the volume of the oil/water, and the microscopic parameters, e.g. the velocity distributions, are analyzed. The results fill the gap in the existing numerical and experimental work, in which the tank is assumed to be stationary, and produce a more reliable prediction on the dynamic process of the oil leakage and the stability of the damaged oil tankers subjected to wave actions. Highlights • A 3D full scale numerical model was developed to estimate dynamic characteristic of crude oil leakage from moving tank. • The process of crude oil leakage was divided into three stages to explore mechanism of crude oil leakage. • The mechanism model and characteristics of crude oil leakage from moving tank were presented. • The flow field and free surface deformation were explored to validate mechanism of crude oil leakage. [ABSTRACT FROM AUTHOR]

A versatile strategy for the synthesis of 6″-functionalized α-GalCers by using NAP ether group for permanent hydroxyl protection was developed, which provide the flexibility necessary for the incorporation of a wide range of functional groups in target molecules including alkyne, azide, thiol that are intolerant to Pd-catalyzed hydrogenolysis as well as other functionalities like carboxylic acid and amine. This strategy is also adaptable to other glycoconjugate synthesis especially those containing clickable tags and unsaturated functionalities. [ABSTRACT FROM AUTHOR]

The trimaran is a high-performance ship of excellent seakeeping performance and stability, which makes it less vulnerable to capsizing. In recent years, strong survivability has increased the applicability of trimaran in unmanned ships. However, compared with the stability and seakeeping, side hulls and the larger width make the trimaran's maneuverability not as good as the traditional monohull. The unified study on trimaran's course keeping and broaching in waves is still limited. In this paper, the navigation of trimaran in oblique stern waves is simulated, and the force and moment by the water-jet impetus and nozzle reflection are simplified. The hybrid method coupling FNPT and CFD is applied to simulate the process of surf-riding and broaching. The characteristics of the surf-riding and broaching of the autopilot trimaran in oblique stern waves are analyzed by changing the working condition of initial forward speed, wave parameters, and initial wave heading. • A hybrid method coupling the FNPT-based QALE-FEM and viscous flow theory is applied to simulate the autopilot of a trimaran in oblique stern waves. The process of the surf-riding and broaching of trimaran in oblique stern waves could be captured. • The surf-riding and broaching of the autopilot trimaran in oblique stern waves of different steepness and wavelength are simulated, and the effect of the wave steepness and wavelength on the occurrence of surf-riding and broaching of trimaran are analyzed. [ABSTRACT FROM AUTHOR]

In present work, a multifunctional magnetic core–shell dendritic silica nanocatalyst Fe 3 O 4 @SiO 2 @Dendritic-SiO 2 -NH 2 -Ag with easy accessibility of active sites and convenient recovery was successfully fabricated by an oil–water biphase stratification coating strategy, and characterized by transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, N 2 adsorption–desorption, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. The as-synthesized nanocatalyst Fe 3 O 4 @SiO 2 @Dendritic-SiO 2 -NH 2 -Ag displayed excellent catalytic activity for the catalytic reduction of 4-nitrophenol and 2-nitroaniline using sodium borohydride in aqueous solution at room temperature due to easy accessibility of active sites. Interestingly, the novel catalyst could be conveniently recovered by magnetic separation from the reaction system and recycled for at least five times without significant loss in activity. These results indicate that the above mentioned approach based on magnetic core–shell dendritic silica Fe 3 O 4 @SiO 2 @Dendritic-SiO 2 provided a useful platform for the preparation of noble metal nanocatalysts with easy accessibility, excellent catalytic activity and convenient recovery. [ABSTRACT FROM AUTHOR]

Highlights: [•] The removal of cadmium using MnO2/o-MWCNTs was studied for the first time. [•] The MnO2/o-MWCNTs which synthesized at pH=5 is the most effective adsorbent. [•] A detailed study for the adsorption process on cadmium removal was obtained. [•] The maximum adsorption capacity was 41.6mgg−1. [•] Adsorption mechanisms were revealed and elucidated in detail. [Copyright &y& Elsevier]