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•The membrane was prepared by using a novel nature-inspired method.•The membrane possesses self-cleaning and antibacterial properties.•The membrane exhibits robust mechanical strength ...and stability.•The membrane features excellent biocompatible and UV-shielding.•Using this membrane can effectively separate various oil-water mixtures.
Fabrication of environmental-friendly, low-cost, and free-standing superhydrophobic nanofibrous membranes with additional functionalities such as self-cleaning and UV-shielding properties is highly demanded for oil-water separation. Herein, we describe the preparation of multifunctional superhydrophobic nanofibrous membrane by using a facile and novel nature-inspired method, i.e., plant polyphenol (tannic acid) metal complex is introduced to generate rough hierarchical structures on the surface of an electrospun polyimide (PI) nanofibrous membrane, followed by modification of poly (dimethylsiloxane) (PDMS). Taking an as-prepared tannic acid − Al3+-based superhydrophobic membrane as an example, it not only exhibits anti-impact, low-adhesive and self-cleaning functions, but also presents excellent performance in the separation of various oil-water mixtures. A high flux up to 6935 l m−2 h−1 with a separation efficiency of over 99% and the oil contents in water below 5 ppm is obtained even after repeating use for twenty separation cycles. Additionally, the membrane exhibits excellent UV-shielding property, attributing to the inherent UV-absorbing ability of tannic acid. Furthermore, the membrane also possesses additional properties including antibacterial activity, good biocompatibility, robust mechanical strength, and excellent resistance to various harsh conditions. These attractive properties of the as-prepared membrane make it a promising candidate for potential applications in industrial oil-contaminated water treatments and oil-water separation.
We estimate the upper mantle temperature of the Antarctic Plate based on the thermoelastic properties of mantle minerals and S velocities using a new 3‐D shear velocity model, AN1‐S. Crustal ...temperatures and surface heat fluxes are then calculated from the upper mantle temperature assuming steady state thermal conduction. The temperature at the top of the asthenosphere beneath the oceanic region and West Antarctica is higher than the dry mantle solidus, indicating the presence of melt. From the temperature values, we generate depth maps of the lithosphere‐asthenosphere boundary and the Curie temperature isotherm. The maps show that East Antarctica has a thick lithosphere similar to that of other stable cratons, with the thickest lithosphere (~250 km) between Domes A and C. The thin crust and lithosphere beneath West Antarctica are similar to those of modern subduction‐related rift systems in East Asia. A cold region beneath the Antarctic Peninsula is similar in spatial extent to that of a flat‐subducted slab beneath the southern Andes, indicating a possible remnant of the Phoenix Plate, which was subducted prior to 10 Ma. The oceanic lithosphere generally thickens with increasing age, and the age‐thickness correlation depends on the spreading rate of the ridge that formed the lithosphere. Significant flattening of the age‐thickness curves is not observed for the mature oceanic lithosphere of the Antarctic Plate.
Key Points
High‐resolution crust/lithosphere temperature model covering the Antarctic Plate
A fossil slab of the Phoenix Plate is found beneath the Antarctic Peninsula
The age‐thickness relation of oceanic lithosphere depends on ridge spreading rate
Urban and suburban road dust samples were collected in the most populated city of China, Shanghai. Size fractions of dust particles were analyzed; metal levels of the dust were also measured. Human ...exposure to individual toxic metals through road dust was assessed for both children and adults. The results showed that dust particles from urban and suburban road were presented similar size distribution pattern, with most particles in the range of 100–400
μm. Urban road dust consisted of higher proportions of inhalable, thoracic and respirable particles with increased risk of adverse effects to human. In general, mean grain sizes of urban road dust were smaller than suburban dust. Total organic carbon contents and levels of Pb, Cd, Cu, Zn, Ni, Cr in urban dust were higher than those of suburban dust. But the concentrations of As and Hg from suburban dust were higher, indicting a different main source. The exposure pathway which resulted in the highest level of risk for human exposed to road dust was ingestion of this material, which was followed by dermal contact. Except for some locations, risk values of both cancer and non-cancer obtained in this study were in the receivable range on the whole. Children had greater health risks than adults. The overall risks of non-cancer in urban area were higher than those in suburban area, but the values of cancer in the two areas were comparable. As for the aggregate noncarcinogenic risk, Pb was of most concern regarding the potential occurrence of health impacts. Of the three carcinogenic metals As, Cr and Cd, the only mean risk higher than 10
−6 was Cr, accounting for a great percentage (95%) of the overall risk of cancer. Hence, potentially adverse health effects arising from Pb and Cr in road dust should arouse wide concern.
Since 2007/2008, seismographs were deployed in many new locations across much of Antarctica. Using the records from 122 broadband seismic stations, over 10,000 Rayleigh wave fundamental‐mode ...dispersion curves have been retrieved from earthquake waveforms and from ambient noise. Using the processed data set, a 3‐D S‐velocity model for the Antarctic lithosphere was constructed using a single‐step surface wave tomographic method, and a Moho depth map was estimated from the model. Using the derived crustal thicknesses, the average ratio of lithospheric mantle and crustal densities of Antarctica was calculated. The calculated density ratio indicates that the average crustal density for Antarctica is much higher than the average values for continental crust or the average density of lithospheric mantle is so low as to be equal to low‐density bound of Archean lithosphere. The latter implies that the lithospheric mantle in much of Antarctica should be old and of Archean age. The East Antarctic Mountain Ranges (EAMOR) represent a thick crustal belt, with the thickest crust (~60 km) located close to Dome A. Very high velocities can be found at depths greater than 200 km beneath parts of East Antarctica, demonstrating that the continental lithosphere extends deeper than 200 km. The very thick crust beneath the EAMOR may represent the collision suture of East Gondwana with Indo‐Antarctica and West Gondwana during the Pan‐African orogeny.
Key Points
High‐resolution crust/lithosphere Vs model covering the whole Antarctic Plate
Lithospheric mantle in most of the Antarctica is significantly old and buoyant
East Antarctic Mountain Ranges are a thick‐crust belt
This paper focuses on the problem of joint detection, tracking, and classification (JDTC) for multiple extended objects (EOs) within a Poisson multi-Bernoulli (MB) mixture (PMBM) filter, where an EO ...is described as an ellipse, and the ellipse is modeled by a random matrix. The EOs are classified according to the size information of the ellipse. Usually, detection, tracking, and classification are processed step-by-step. However, step-by-step processing ignores the coupling relationship between detection, tracking, and classification, resulting in information loss. In fact, detection, tracking, and classification affect each other, and JDTC is expected to be beneficial for achieving better overall performance. In the multi-target tracking problem based on RFS, the overall performance of the PMBM filter satisfying the conjugate priors has been verified to be superior to other filters. Specifically, the PMBM filter propagates multiple MB simultaneously during iterative updates and model the distribution of hitherto undetected EOs. At present, the PMBM filter is only applied to multiple extended objects tracking problem. Therefore, we consider using the PMBM filter to solve the JDTC problem of multiple EOs and further improve JDTC performance. Furthermore, the closed-form implementation based on the product of a gamma Gaussian inverse Wishart (GGIW) and class probability mass function (PMF) is proposed. The details of parameters calculation in the implementation process and the derivation of class PMF are presented in this paper. Simulation experiments verify that the proposed algorithm, named the JDTC-PMBM-GGIW filter, performs well in comparison to the existing JDTC strategies for multiple extended objects.
Sexually transmitted and blood-borne infections (STBBIs) is a major public health concern in China. This study assessed the overall trends in STBBIs to improve the comprehensive understanding of the ...burden of STBBIs and provide evidence for their prevention and control. Data for the period from 2005 to 2021 were analyzed across China on infections with hepatitis B or C; syphilis; gonorrhea; and HIV infection. Trends, annual percent change (APC), and average annual percent change (AAPC) in diagnosis rate was analyzed using joinpoint regression models for the five STBBIs together or individually. From 2005 to 2021, the overall diagnosis rate of all five STBBIs increased, with an AAPC of 1.3% 95% confidence interval (CI) -0.5% to 3.1%. Diagnosis rates of HIV, syphilis and hepatitis C increased individually, but it decreased for infections of hepatitis B and gonorrhea. Joinpoint analysis identified four phases in diagnosis rate of hepatitis C; three phases in diagnosis rate of hepatitis B, HIV infection, and syphilis; two in diagnosis rate of gonorrhea infection. Despite national efforts to prevent and control STBBIs, their overall diagnosis rate has continued to rise in China, and they remain an important public health challenge. Further efforts should be made to educate the general population about STBBIs, particularly HIV. Interventions targeting vulnerable groups should be adopted and their efficacy monitored through regular analysis of trends.
Atmospheric samples and surface seawater collected on a Chinese Antarctic Research Expedition (CHINARE) transect are used to investigate sources and production of nitrate (NO3−) in the atmosphere and ...its contribution to the surface NO3− pool in the ocean. Most atmospheric NO3− is concentrated on intermediate size particles, and much higher concentrations were observed in the northern hemisphere than in the high southern latitudes. Isotopes of NO3− (δ15N, δ18O and Δ17O) suggest that elevated atmospheric NO3− in coastal areas was associated with human activities, while NO3− in the high southern latitudes tends to be influenced by precursor Antarctic snowpack emissions driven by photolysis. In general, no clear association was found between the isotopes of surface seawater and atmospheric NO3−, suggesting that the ocean is unlikely to be an important direct source of atmospheric NOx on this transect. A significant linear relationship between δ18O and Δ17O of NO3− is used to interpret important pathways for NO3− production. In the tropics, >59% of atmospheric NO3− is produced via OH oxidation of NO2, while the elevated oxygen isotopic ratios (δ18O and Δ17O) in the high southern latitudes suggest increased NO3− production via BrO and/or DMS pathways assuming a minor contribution of the N2O5 channel. In surface seawater, high NO3− concentrations are present in the coastal areas and in the Southern Ocean. In coastal areas of China, positive Δ17O values in seawater NO3− (1.7 ± 1.0‰) provide direct evidence of uncycled atmospheric deposition contribution, with a calculated contribution of at least 2-3% to total surface NO3−. A Δ17O=0 was found everywhere else in seawater, suggesting that atmospheric deposition has a minimal presence in the surface NO3− pool. Near Antarctica, deposition of atmospheric NO3− with extremely low δ15N (<−30‰) could lower δ15N found in sea ice, and this process could be isotopically important to evaluate nitrogen cycling in sea ice.
•Concentration and isotopic composition of NO3− show notable latitudinal gradients.•Atmospheric NO3− is mainly produced via OH oxidation in the tropics.•The high southern latitudes show an increased importance of BrO or DMS pathways.•Positive Δ17O of seawater NO3− is found in coastal waters and Δ17O≈0 in other areas.•Atmospheric deposition near Antarctica can lower δ15N of NO3− in sea ice.
This ecological study examined the individual and joint impacts of natural-human factors on the spatial patterns of maternal and child health status in China at the provincial scale in 2020. We ...considered natural factors (forest coverage, average temperature, and total sulfur dioxide and particulate matter emissions) and human factors (economic development, urbanization, healthcare access, and education level). We combined maternal, infant, and under-five mortality rates into a composite maternal and child health index using the entropy method. The spatial autocorrelation analysis of this index highlighted distinct health patterns across provinces, whereas the geodetector method assessed the effects of natural-human factors on the patterns. A notable east-central-west stepwise decline in health status was observed. Global Moran's I showed positive spatial clustering, with high-high clustering areas in the Yangtze River Delta and low-low clustering areas in western regions. Factor detection identified eight significant natural-human factors impacting maternal and child health, with total sulfur dioxide emission density having the greatest impact. The interaction between average schooling years and total sulfur dioxide emission notably affected maternal and child health patterns. The study concludes that natural-human factors critically affect the spatial distribution of maternal and child health.
Ice-sheet development in Antarctica was a result of significant and rapid global climate change about 34 million years ago. Ice-sheet and climate modelling suggest reductions in atmospheric carbon ...dioxide (less than three times the pre-industrial level of 280 parts per million by volume) that, in conjunction with the development of the Antarctic Circumpolar Current, led to cooling and glaciation paced by changes in Earth's orbit. Based on the present subglacial topography, numerical models point to ice-sheet genesis on mountain massifs of Antarctica, including the Gamburtsev mountains at Dome A, the centre of the present ice sheet. Our lack of knowledge of the present-day topography of the Gamburtsev mountains means, however, that the nature of early glaciation and subsequent development of a continental-sized ice sheet are uncertain. Here we present radar information about the base of the ice at Dome A, revealing classic Alpine topography with pre-existing river valleys overdeepened by valley glaciers formed when the mean summer surface temperature was around 3 °C. This landscape is likely to have developed during the initial phases of Antarctic glaciation. According to Antarctic climate history (estimated from offshore sediment records) the Gamburtsev mountains are probably older than 34 million years and were the main centre for ice-sheet growth. Moreover, the landscape has most probably been preserved beneath the present ice sheet for around 14 million years.
In this article, an Adaptive Hamiltonian-Based Energy Control (AHBEC) with a built-in integrator is introduced for the Proton-Exchange Membrane Fuel Cell (PEMFC) hybrid power-conversion system. The ...presented additional built-in integrator is based on the Lyapunov and Hamiltonian functions. Unlike previous works, the control strategy proposed in this article aims to regulate the output current of the PEMFC stack, i.e., to provide sufficient power support to the load, and the integrator is built into the control loop in order to eliminate the steady-state current error caused by external disturbances and model parameter uncertainties. The large-signal stability of the whole system is demonstrated by selecting a suitable Lyapunov-candidate function. An experimental setup is constructed in the laboratory to verify the proposed control strategy. The experimental results demonstrate the robustness and effectiveness of the designed energy-control approach.
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