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Solar‐driven interfacial evaporation is an emerging desalination technology that can potentially relieve the freshwater scarcity issue. To obtain high and continuous evaporation rates for all‐weather, chemically engineered structural materials have been widely explored for simultaneous photothermal and electrothermal conversion. However, many previously reported fabrication processes involve poor integration and considerable energy loss. Herein, a scalable photo‐electro‐thermal textile is proposed to enable high efficiency, long‐term salt rejection, and solar‐driven desalination. Specifically, the photo‐electro‐thermal yarns with a core (commercial electric wire)‐shell (polypyrrole‐decorated Tencel) structure realize the integration of electrothermal and photothermal conversion. The wrapping eccentricity of 1.53 mm and pitch of 3 T cm−1 for the electric wire are rationally regulated to achieve a high surface temperature of over 52 °C at a 3 V DC input. As a result, exceptional and stable evaporation rates of 5.57 kg m−2 h−1 (pure water) and 4.89 kg m−2 h−1 (3.5 wt.% brine) under 1 kW m−2·radiation with a 3 V input voltage are realized. Practical application shows that the textiles can achieve high water collection of over 46 kg m−2 d−1 over the whole day of operation. The constructed photo‐electro‐thermal textile‐based evaporator provides an effective method for commercial and scalable photo‐electro‐thermal conversion to achieve high‐performance and salt‐resistant solar‐driven desalination. [ABSTRACT FROM AUTHOR]

Energy generation systems based on FC (fuel cell) are viewed as a viable substitute for those that simply rely on thermodynamic cycles in the power production field. In this paper, a 10-stack SOFC systems performance and optimization of that utilizing a newly improved optimizer known as the Fractional-order Kho-Kho optimization method will be presented in this paper. The multi-objective optimization approach is applied in the optimization phase to achieve the desired performance goals for the SOFC system. With the help of this technique, the desired system can be optimized in accordance with two objective functions: first, the electric power of the system can be maximized, while the equalized price of the electricity produced is minimized. Then, the electrical efficiency of the system can be maximized, while the equalized price of the electricity produced is minimized. The results show that, by reducing the coefficient and increasing efficiency, optimal solutions were achieved with higher electricity prices. It is observed that an increase in energy prices led to a 9% increase in productivity, whereas a 15% increase resulted in only a 2% increase. The findings demonstrate that multi-objective optimization may be used as a sophisticated analytical tool as well as a guiding element for decision-makers utilizing such a system. [ABSTRACT FROM AUTHOR]

The downwash airflow generated by the rotors can enhance the penetration of pesticide droplets, allowing them to penetrate deeper into the canopy and more comprehensively control pests. Downwash air will produce a "wind vortex" in plant canopy, and the parameters of a "wind vortex" represent the effect of pesticide deposition to a certain extent. To obtain the corresponding relationship between wind vortices and flight parameters and control the effect of pesticide spraying, this paper carried out unmanned aerial vehicle (UAV) flight experiments in the field. Wind vortices were generated in rice canopy by downwash airflow, and the parameters of wind vortices were obtained by identifying wind-vortex images using the inter-frame difference method. The wind-vortex parameter control model was established, which can calculate the altitude and speed of the UAV when applying pesticide according to the target wind-vortex parameter. The deviations in the altitude were determined to be 0.67 and 0.43 m, and the deviations in the speed were 0.29 and 0.35 m/s during downwind and headwind UAV operations, respectively. The model relation functions were established, and their accuracies were found to be 97.1%, 92.3%, 69%, and 58% (downwind), and 97%, 78.4%, 62%, and 57% (upwind), respectively, indicating that downwind UAV operation leads to a clear relation between the wind-vortex parameters and the UAV-flight parameters. The model establishes the corresponding relationship between the wind-vortex parameters and flight parameters, which provides a theoretical basis for studying the precise application control method of UAV. [ABSTRACT FROM AUTHOR]

The terahertz stealth and shielding performance of a new type of two-dimensional material, borophene, has been studied theoretically and experimentally. Studies have shown that borophene materials have good terahertz stealth and shielding properties. First-principles calculations show that compared with single-layer borophene, few-layer borophene has good terahertz stealth and shielding performance in the range of 0.1~2.7 THz. In the range of 2~4 layers, the terahertz stealth and shielding performance of few-layer borophene increases with the increase of the number of layers. The finite element simulation calculation results also confirmed this point. Using the few-layer borophene prepared by our research group as a raw material, a PDMS composite was prepared to verify the terahertz stealth and shielding performance of the few-layer borophene. In the ultra-wide frequency range of 0.1~2.7 THz, the electromagnetic shielding effectiveness (EMI SE) of the PDMS material mixed with few-layer borophene can reach 50 dB, and the reflection loss (RL) can reach 35 dB. With the concentration of few-layer borophene increasing, the terahertz stealth and shielding effectiveness of the material is enhanced. In addition, the simultaneous mixing of few-layer borophene and few-layer graphene will make the material exhibit better terahertz stealth and shielding performance compared with mixing separately. [ABSTRACT FROM AUTHOR]

Clustering analysis, as one of the important methods in data mining technology, merely provides a method for the research and analysis of large amounts of data. Starting with the most important nodes, this paper divides clustering based on data field characteristics. The sensitivity pruning algorithm is then used to further adjust and optimize the structure of the fuzzy neural network, allowing the network to automatically learn the structure and parameters of the system in different environments and obtain the optimal control rules. Finally, the clustering function brings the algorithm's output result to a close. The experimental results show that the adaptive clustering algorithm of complex networks presented in this paper can effectively improve network cluster division, reduce algorithm time complexity, and avoid the problem of providing the number of cluster structures in advance. This method's cluster structure efficiency can reach 97.6 percent, and its highest clustering accuracy can reach 96.8 percent. The adaptive clustering algorithm proposed in this paper not only overcomes the traditional algorithm's flaws, such as the need to predetermine the number of clusters and the clustering result being dependent on the initial clustering center selection, but also has ideal clustering accuracy. This study introduces a novel and more effective method for addressing the difficult problems of practical complex control systems. [ABSTRACT FROM AUTHOR]

Harvesting energy from environmental moisture is a promising technique for sustainable electric power resource. Herein, a new scalable fabrication method for flexible moisture-electric energy transformation device by dispersing or direct printing carbon dots (CDs) on paper is reported. A facile strategy for self-establishing ionic gradient on both sides of the device by constructing an asymmetric structure (the side of device is encapsulated) is proposed, which avoids prior processing of the materials for building asymmetric functional groups. The carboxyl groups on CDs near the open side of the device ionize more protons than that near the closed side, resulting in a potential drop across the device due to the concentration difference of the released protons on the two sides. The device can produce a sustainable voltage of −40 mV for over 100 min at a fixed humidity value. In addition, the device responds to direct touching of a finger or human exhalation, thus indicating its great potential for applications in electronic skins and humidity sensors. [ABSTRACT FROM AUTHOR]

A total of 141 surface sediments were collected and analyzed for their geochemistry, total organic carbon, and grain size to assess the heavy metal pollution in the Bohai and Yellow Seas. The enrichment factor (EF) and geoaccumulation index ( I geo ) of Cu, Pb, Zn, Cr, Cd, Ni, As, and Hg were calculated to assess anthropogenic contamination, and the results suggest that moderate Pb, Cd, and As contamination occurs in the study area. Sediment quality guidelines were applied to assess the adverse biological effects of these metals. The spatial distribution of the mean Effects Range-Median quotient for the vast majority of the study area is between 0.1 and 0.5, indicating low impact and potential negative biological effects. Multivariate analysis indicates that Cu, Pb, Zn, Cr, and Ni resulted primarily from lithogenic sources, whereas As, Cd, and Hg were mainly attributed to anthropogenic sources. [ABSTRACT FROM AUTHOR]

A large-scale survey for offshore aggregates is carried out on the northern shelf of the East China Sea. Results show that most of them are directly exposed in the Yangtze Shoal and the linear sand ridges system at water depths 25-55 m and 60-120 m, respectively. The components of these deposits belong to fine aggregates in terms of the fineness modulus. The potential resources are as high as 147.8 × 1012 kg for the Yangtze Shoal yet only 36.68 × 1012 kg for the sand ridges area, respectively. A preliminary feasibility analysis suggests that the Yangtze Shoal is suitable for dredging under the present conditions of technology and economy. [ABSTRACT FROM AUTHOR]

Graphene shows great potential applications in functional coating, electrodes, and ultrasensitive sensors, but high-yield and scalable preparation of few-layer graphene (FLG) by mechanical exfoliation method is still a formidable challenge. In this work, a novel two-step method for high-yield preparation of FLG is developed by combining resonance ball milling and hydrothermal treatment. During the resonance ball milling process, the utilization of magnetic Fe3O4 nanoparticles as a new "particle wedge" is beneficial to facilitate fragment and delamination of graphitic layers. In addition, further hydrothermal treatment can enhance ball milling product (BMP) exfoliation because of the shear force driven by the Brownian motion of various molecules at high temperature and high pressure. As expected, the two-step method can have high exfoliation efficiency up to 92% (≤10 layers). Moreover, the FLG nanosheet ink can easily achieve the formation of FLG coatings on the surface of various substrates, resulting in good electrical conductivity, which possesses potential applications in various fields including functional coating, energy storages, and electrochemical sensors, etc. Our work provides a new-fashioned strategy for mechanical large-scale production of graphene. [ABSTRACT FROM AUTHOR]

The East China Sea is a typical marginal sea and is characterized by strong land–sea interaction and paleoenvironmental changes during the late Quaternary with sea-level fluctuations. In this study, late Quaternary sedimentary stratigraphy and facies on the outer shelf of the East China Sea were reconstructed by using high-resolution seismic reflections and combining evidences from lithology, microfossil assemblages, element geochemistry and geochronology of borehole SFK-1. Sedimentary sequence consists of nearshore facies of forced regression formed during the late marine isotopic stage 3, tide-influenced fluvial and estuarine facies during the last glacial maximum, incised-valley fill and estuarine-tidal flat facies during the deglacial transgression, buried and quasi-active tidal sand ridge facies during the postglacial and Holocene periods. The sea-level fluctuation and paleo-river and sea interaction primarily controlled the stratigraphic framework and sedimentary facies on the outer shelf during the late Quaternary. This study confirms the occurrence of paleo-river channels and relating deposits on the outer shelf. Paleo-fluvial deposits accumulated during the last glacial maximum albeit with strong tidal reworking, and tide-dominated estuarine facies are recognized during the early deglacial transgression. The previously-recognized delta facies might not have formed on the outer shelf because of the low sediment supply and/or strong tidal reworking. [ABSTRACT FROM AUTHOR]

Abstract: The Old Huanghe (Yellow River) delta in Jiangsu Province, China, has suffered intense erosion since the river mouth changed from the Yellow Sea to the Bohai Sea in 1855, and this erosion has since been the dominant sediment source to the Yellow Sea and East China Sea. To analyze the topographic and bathymetric changes to the Old Huanghe delta area and derive a regional sediment budget, we extracted shoreline positions and bathymetry from charts and maps published since 1875 and georectified these data into a common coordinate system, combining them with extensive single-beam bathymetric survey data acquired between 2002 and 2008 off Jiangsu Province. The results show continuous seabed erosion throughout the 20th century, consisting of the retreat of shoreface morphology in the nearshore zone (mostly <15-m depth) and deepening of the flat seabed offshore (15 to ~20m). Off the abandoned river mouth of the Old Huanghe, historically persistent sandbanks disappeared and other recent sandbanks shrank. Sediment yielded by coastal erosion from depths of <20m has amounted to >790 Mt annually on average for the last 100 years. Of this very large amount of sediment, ~25% is deposited on the offshore slope in the western Yellow Sea, another 20–25% is deposited along the south Jiangsu coast as far as the Changjiang (Yangtze) river delta, and the rest is transported southeastward along the mud belt that crosses the central Yellow Sea to south of Cheju Island in the East China Sea. This amount is an order of magnitude larger than the sediment supply from the modern Huanghe River to the Yellow Sea and also greatly exceeds the present sediment discharge of the Changjiang River. [Copyright &y& Elsevier]

In carbon allotropes, a series of topological semi-metals have been predicted, but both novel electronic properties and mechanical characteristics, e.g. , a negative Poisson's ratio (NPR), are rarely discovered in the same sp 2 type system. Here, a new three-dimensional carbon network, named WZGN, constructed from distorted one-dimensional zigzag graphene nanoribbons is proposed. The stability of the system is fully ensured by the phonon dispersion, AIMD simulation, and binding energy calculations. Besides, it is found that the system holds both topologically protected nodal line semi-metal properties together with an NPR property. Especially, the value of the NPR can exceed -0.36 when 21% uniaxial tensile strain along the c '-direction is applied. Our findings point out that nodal line semi-metals can be compatible with intrinsic NPR properties in a wide strain range in carbon systems with sp 2 hybridization, suggesting possible applications in mechanical and electronics fields.

Phosphorescence shows great potential for application in bioimaging and ion detection because of its long-lived luminescence and high signal-to-noise ratio, but establishing phosphorescence emission in aqueous environments remains a challenge. Herein, we present a general design strategy that effectively promotes phosphorescence by utilising water molecules to construct hydrogen-bonded networks between carbon dots (CDs) and cyanuric acid (CA). Interestingly, water molecules not only cause no phosphorescence quenching but also greatly enhance the phosphorescence emission. This enhancement behaviour can be explained by the fact that the highly ordered bound water on the CA particle surface can construct robust bridge-like hydrogen-bonded networks between the CDs and CA, which not only effectively rigidifies the C=O bonds of the CDs but also greatly enhances the rigidity of the entire system. In addition, the CD-CA suspension exhibits a high phosphorescence lifetime (687 ms) and is successfully applied in ion detection based on its visible phosphorescence.

The second near-infrared window emission (1.0-1.7 μm, NIR-II) has received extensive attention with the advantages of negligible tissue scattering, reduced autofluorescence, and less background noise. Here a novel analysis platform based on quantum dots (QDs) for highly selective detection of Zn 2+ and Cd 2+ with an enhanced NIR-II fluorescence is reported for the first time. We have developed a facile two-step route to synthesize the water-soluble Ag 2 S QDs, constituting of a green hydrothermal process and followed surface ligands exchange. Surface passivation was proposed to be the mechanism for the enhanced fluorescence. The added Zn 2+ or Cd 2+ could react with the surface thioglycollic acid to form Zn-thiol or Cd-thiol complex passivation shell, which restored surface defects and suppressed nonradiative recombination pathway. The detection platform exhibited a linear relationship between the ion concentrations and enhanced fluorescence and had a detection limit as low as 760 nM for Zn 2+ and 546 nM for Cd 2+ at pH = 7.4. Furthermore, the as-synthesized Ag 2 S QDs showed good robustness in real sample matrix and were demonstrated to be able to detect exogenous Zn(II) in cells. These properties suggest potential applications of detection of Zn 2+ in biology and Cd 2+ in environment via the NIR-II fluorescent Ag 2 S QDs.