In marine and offshore engineering, the presence of air in the water plays a significant role in influencing impact pressures during water entry events. Owing to limited research on the impact loads of aerated water entry, this study aims to explore the effect of aeration on water entry impact pressures. A comprehensive experimental investigation on pure and aerated water entry of a wedge with a 20° deadrise angle was presented. The wire-mesh sensor (WMS) technology was proposed to accurately quantify the spatial and temporal distributions of void fractions in multiphase environments. The WMS provides reliable and consistent measurements at varying void fractions, as validated against image-based methods. The results indicated that the aeration reduced peak impact pressures by up to 33 %, and extended pressure duration, with a linear relationship between impact pressure and void fraction. Furthermore, the probability distribution of peak pressures conformed well to both the generalised extreme value and Weibull distributions, with the void fraction exerting a strong influence on pressure distribution parameters. These findings suggest that controlled aeration can effectively mitigate impact loads, offering practical implications for marine structure design.

Motivated by new examples of functional Banach spaces over the unit disk, arising as the symbol spaces in the study of random analytic functions, for which the monomials $\{z^n\}_{n\geq 0}$ exhibit features of an unconditional basis yet they often don’t even form a Schauder basis, we introduce a notion called solid basis for Banach spaces and p-Banach spaces and study its properties. Besides justifying the rich existence of solid bases, we study their relationship with unconditional bases, the weak-star convergence of Taylor polynomials, the problem of a solid span and the curious roles played by c0. The two features of this work are as follows: (1) during the process, we are led to revisit the axioms satisfied by a typical Banach space of analytic functions over the unit disk, leading to a notion of $\mathcal{X}^\mathrm{max}$ (and $\mathcal{X}^\mathrm{min}$), as well as a number of related functorial constructions, which are of independent interests; (2) the main interests of solid basis lie in the case of non-separable (p-)Banach spaces, such as BMOA and the Bloch space instead of VMOA and the little Bloch space.

Broomcorn millet and foxtail millet were first cultivated in Neolithic China then the process spread west across Asia during the Bronze Age. But the distinctive ceramic, and later bronze, vessels utilised in East Asian cuisines for boiling and steaming grains did not move west alongside these crops. Here, the authors use measurements of 3876 charred millet grains to evaluate regional variations and implications for food preparation. In contrast to wheat grains, which became smaller as their cultivation moved east, millet grains became larger as they spread from northern China into Inner Asia and Tibet. This indicates the decoupling of millets from associated cooking techniques as they reached geographical and cultural areas.

Ion adsorption-type rare earth deposits (IADs) are developed via prolonged weathering of REE-rich volcanic and metamorphic rocks. Intense magmatic activity which occurred during the Yanshanian (199.6–65.5 Ma) and Caledonian periods (542–359.2 Ma) provided an abundant material basis for the formation of IADs in South China. High concentrations of REE and the high proportion of ion-exchangeable REE were found in the Maofeng Mountain regolith, Guangzhou city. However, the geochemical patterns and mechanisms of REE enrichment in the regolith were still poorly understood. The present study investigated the regolith profile (0–8 m) developed in Maofeng Mountain based on metallogenic and geochemical characteristics, sequential extraction, and physical and chemical parameters of the regolith profile. The bedrock contained abundant REE resources (245–287 mg kg–1) and the chondrite-normalized REE patterns showed the enrichment of light REE (LREE) and negative cerium (Ce) and europium (Eu) anomalies. The distribution patterns of REE in the bedrock were inherited by the regolith. REE enrichment of the regolith occurred mainly in the completely weathered layer (B1, B2, and B3 horizons), particularly in the depth range 2.5–4.5 m (849–2391 mg kg–1). The position of REE enrichment was controlled by the soil pH (5.52–6.02), by the amount of kaolinite and halloysite, and by the permeability of the metamorphic rock. In the REE-enriched horizon (2–8 m), the REE were hosted mainly in ion-exchangeable fractions (75–2158 mg kg–1), representing 79% of the total REE. Given the pH of 4.73–6.02, REE fractionation driven by the adsorption of kaolinite was limited. Fe–Mn (oxyhydr)oxides played an important role in REE enrichment and the reducible fraction holds up to 21% (139 mg kg–1) of the total REE. The enrichment of LREE was observed in the reducible fraction potentially because of the preferential release of LREE from the LREE-bearing minerals (monazite) and then scavenged by Fe–Mn (oxyhydr)oxides. Positive Ce anomalies (Ce/Ce*: 10) were found in the reducible fraction because trivalent Ce was oxidized by Fe–Mn (oxyhydr)oxides to cerianite (CeO2). The present study helps to understand the enrichment and fractionation of REE in the IADs of South China.

Aiming at the problem that the covariance matrix includes the desired signal and the signal steer vector mismatches will degrade the beamforming performance, an effective robust adaptive beamforming (RAB) approach is presented in this paper based on a residual convolutional neural network (RAB-RCNN). In the presented method, the RAB-RCNN model is designed by introducing a residual unit, which can extract the deeper features from the signal sample covariance matrix. Residual noise elimination and interferences power estimation are utilized to reconstruct the desired signal covariance matrix, and correct the mismatched steering vector (SV) by the eigenvalue decomposition of the reconstructed desired signal covariance matrix. The projection method is utilized to redesign the signal interference-plus-noise covariance matrix. Furthermore, the beamforming weight vector is calculated with the two parameters obtained before and used as the label of the RAB-RCNN model, The trained model can rapidly and precisely output the predicted beamforming weight vector without complex matrix operations, including the matrix inversion of the signal covariance matrix, so that the calculation time can be reduced for beamforming. Simulations demonstrate the robustness of the presented approach against SV mismatches due to the direction-of-arrival estimation error, sensor position error, and local scattering interference.

A low-profile wideband circularly polarized (CP) metasurface antenna is demonstrated for C-band applications. The metasurface consists of 4 × 4 square patches with Z-shaped slots. Characteristic mode analysis is used to investigate the modal behavior of the metasurface, and a pair of degenerate modes is chosen as the operating modes. The CP radiation is realized by exciting a pair of degenerate modes of the metasurface through a slot antenna, which is used as a feed structure with a 90° phase difference. The CP bandwidth is further widened by combining the resonance modes of the metasurface and slot antenna. The measured results show that the −10 dB impedance bandwidth of the antenna is 3.47–4.76 GHz, and the 3 dB axial ratio bandwidth is 3.5–4.9 GHz with a peak gain of 6.9 dBic. Moreover, the antenna exhibits well left-hand CP radiation performances with a low profile of 0.046λ0.

The association between time-restricted eating (TRE) and the risk of non-alcoholic fatty liver disease (NAFLD) is less studied. Moreover, whether the association is independent of physical exercise or diet quality or quantity is uncertain. In this nationwide cross-sectional study of 3813 participants, the timing of food intakes was recorded by 24-h recalls; NAFLD was defined through vibration-controlled transient elastography in the absence of other causes of chronic liver disease. OR and 95 % CI were estimated using logistic regression. Participants with daily eating window of ≤ 8 h had lower odds of NAFLD (OR = 0·70, 95 % CI: 0·52, 0·93), compared with those with ≥ 10 h window. Early (05.00–15.00) and late TRE (11.00–21.00) showed inverse associations with NAFLD prevalence without statistical heterogeneity (Pheterogeneity = 0·649) with OR of 0·73 (95 % CI: 0·36, 1·47) and 0·61 (95 % CI: 0·44, 0·84), respectively. Such inverse association seemed stronger in participants with lower energy intake (OR = 0·58, 95 % CI: 0·38, 0·89, Pinteraction = 0·020). There are no statistical differences in the TRE-NAFLD associations according to physical activity (Pinteraction = 0·390) or diet quality (Pinteraction = 0·110). TRE might be associated with lower likelihood of NAFLD. Such inverse association is independent of physical activity and diet quality and appears stronger in individuals consuming lower energy. Given the potential misclassification of TRE based on one- or two-day recall in the analysis, epidemiological studies with validated methods for measuring the habitual timing of dietary intake are warranted.

A two-element low-profile closely coupled dual-band MIMO antenna is demonstrated for WiMAX applications. Based on the principle of metasurface (MTS) decoupling, a double-layer MTS consisting of pairs of elliptic patches with two different sizes is proposed. The MTS is loaded above a coupled dual-band MIMO antenna, and the mutual coupling in the lower and upper band is reduced by the larger and smaller elliptic patches, respectively. The edge-to-edge distance of antenna elements is only 0.01λ0 (λ0 is the free-space wavelength at 2.6 GHz). The measured results show that the working bandwidths of the MIMO antenna are 2.5–2.69 and 3.4–3.69 GHz. The −10 dB impedance bandwidths in two bands are 8.83% (2.49–2.72 GHz) and 8.50% (3.38–3.68 GHz), and the isolation between antenna elements is enhanced by 13.5 and 18.4 dB in two bands, respectively. Moreover, broadside radiation performances in two bands are obtained.

Studies of ‘food globalisation’ have traced the dispersal of cereals across prehistoric Eurasia. The degree to which these crops were accompanied by knowledge of soil and water preparation is less well known, however. The authors use stable isotope and archaeobotanical analyses to trace long-term trends in cultivation practices on the Loess Plateau (6000 BC–AD 1900). The results indicate that ancient farmers cultivated grains originating in South-west Asia and used distinct strategies for different species. Barley was integrated into pre-existing practices, while wheat was grown using novel soil and water management strategies. These distinct approaches suggest that the spread of prehistoric crops and knowledge about them varied by local context.

Supercapacitor has received intense interest due to its high-charge/discharge rate and high-power density. C/Fe2O3 layer with different C/Fe ratios were synthesized by a solution-based approach for supercapacitor application. The influence of synthesis conditions on their electrochemical performances was investigated. Cobalt was added into C/Fe2O3 and significant improved its performance. The optimal C/Fe2O3 sample gives a high specific capacitance of 85.3 F/g and the addition of Co3O4 further increase the capacitance of obtained C/Fe2O3/Co3O4 to 144.4 F/g at 5 A/g. This work demonstrates an efficient supercapacitor application of low-cost metal oxides and facile solution-based synthesis approach.

Astronomy cloud computing environment is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences). Based on virtualization technology, astronomy cloud computing environment was designed and implemented by China-VO team. It consists of five distributed nodes across the mainland of China. Astronomer can get compuitng and storage resource in this cloud computing environment. Through this environments, astronomer can easily search and analyze astronomical data collected by different telescopes and data centers , and avoid the large scale dataset transportation.

A novel CuWO4/Cu1−x Znx WO4/ZnWO4 hybrid photocatalyst with sandwiched heterojunction structure was prepared by a one-port synthesis with Zn doping into CuWO4. The crystalline structure, optical, and morphological properties as well as photocatalytic performance of the as-prepared hybrid photocatalyst were studied. By adjusting the amount of Zn doped, the optimal doping level was determined to be 0.1 wt% Zn2+. More than 80% photocataytic degradation of rhodamine B was achieved within 20 min over 0.1 wt% Zn2+ doped CuWO4, while only 20% was achieved for the pure CuWO4. The enhancement was proposed to be due to the formation of a CuWO4/Cu1−x Znx WO4/ZnWO4 sandwiched heterojunction. Such tandem type heterojunction was found to be efficient for charge separation compared to traditional single heterojunction, which, in turn, resulted in a significantly enhanced photocatalytic activity. Our finding is also expected to be valuable for the exploration of CuWO4-material as a new group of efficient photocatalysts.

Cu2ZnSnSe4 (CZTSe) precursor films were deposited by one-step RF sputtering process at room temperature under various sputtering power, and then films were annealed at different pressure of 10-3 Pa and 100 Pa. Films annealed at high vacuum of 10-3 Pa exhibit significant loss of Sn element and they construct with two phases of Cu1.8Se and ZnSe. Higher annealing pressure at 100 Pa can drastically reduce the loss of Sn element and result in single kesterite CZTSe phase of the annealed films. Loss of Se element is found in all the annealed films and the values of [Se]/[Metal] and [Sn]/[Zn] are related with sputtering power. High vacuum annealed films show cracks and porous structure on the surface, meanwhile, films annealed at 100 Pa show compact, densely packed homogeneous morphology.

The clogging of the Submerged Entry Nozzle (SEN) duringbillet continuous casting of mid-carbon steel is studied.Clogging materials and inclusions in steel samples taken atladles, tundish and billets are investigated. The total oxygen onthe whole section of the billet is measured. Steel cleanliness atunsteady casting states, including cast start, ladle change, SENchange, cast end, and the special unsteady pouring periodinduced by SEN clogging, are studied. Fluid flow and inclusionmotion and entrapment to SEN surface are also simulated.

In this study, we characterized the structural defects in blue and green GaInN/GaN LEDs grown on c-plane bulk GaN and sapphire substrates. Low density large V-defects with diameters around 600 nm were found in the blue LEDs on bulk GaN. They were initiated by edge-type threading dislocations (TDs) around the homoepitaxial growth interface. On the other hand, a high density 7×109 cm−2 of smaller V-defects with sidewalls on {1101} facets was observed in the active region of green LEDs on sapphire. Their diameter ranges from 150 to 200 nm. Misfit dislocations (MDs) generated in the quantum wells are found to initiate these V-defects. With optimizing the epitaxial growth conditions, the generation of MDs and their smaller V-defects was largely suppressed. As a result, the light output power improved by one order of magnitude. For green LEDs on bulk GaN, another unique type of defect was found in the active region: an inclined dislocation pair (IDP). In it a pair of dislocations propagate at a tilt angle of 18 to 23° from the [0001] growth direction towards <1100>. This defect seems to be a path of strain relief in the high indium composition quantum wells.

In order to study the preferred crystal orientations of Mg-Zr-O composite protective layers in PDP, Mg-Zr-O composite protective layers were deposited by Electron-beam Evaporator using (MgO+ZrO2) powder mixture as evaporation source material. X-ray diffractometer (XRD) was used to determine preferred crystal orientations of Mg-Zr-O composite protective layers, surface morphologies of films were analyzed by FESEM and voltage characteristics were examined in a testing macroscopic discharge cell of AC-PDP. On the basis of experimental analysis, the influence of oxide addition and deposition conditions on preferred orientations of Mg-Zr-O composite protective layers were investigated. The results showed that the preferred orientations of Mg-Zr-O films were determined by lattice distortion of MgO crystal. The deposition conditions have great effects on the preferred orientations of Mg-Zr-O films. The preferred orientations affect voltage characteristics through affecting surface morphology of Mg-Zr-O films. A small amount of Zr solution in MgO can decrease firing voltage compared with using pure MgO film. Firing voltage is closely related with the [ ZrO2/(MgO+ZrO2)]ratio of evaporation source materials.

A convenient way is given in this paper to calculate the effective secondary electron emission coefficient (γ $_{\it eff}$ ) of protective layers in AC-PDP by fitting breakdown voltage curves. Based on the analysis of chemical kinetics of gas discharging in Plasma Display Panels, we deduced an empirical equation of self-sustaining discharge condition for Penning gas mixture in terms of Townsend breakdown criteria. It was used to calculate the breakdown voltage curves of Ne-Xe/MgO, Ne-Ar/MgO, Ne/MgO, Ar/MgO and Xe/MgO in a testing macroscopic discharge cell of AC-PDP. The effective secondary electron emission coefficients were derived by comparing the breakdown voltage curves obtained from the empirical equation with the experimental data of breakdown voltages. The γ $_{\it eff}$ results showed a good conformity with the secondary electron emission coefficients in literatures. The empirical equation can be used as a convenient approach to research gas discharge characteristics and the effective secondary electron emission behaviors in plasma display panels.