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Abstract Understanding the determinants of biodiversity in fragmented habitats is fundamental for informing sustainable landscape development, especially in urban landscapes that substantially fragment natural habitat. However, the relative roles of landscape and habitat characteristics, as emphasized by two competing frameworks (the island biogeography theory and the habitat diversity hypothesis), in structuring species assemblages in fragmented habitats have not been fully explored. This study investigated bird assemblages at 26 habitat patches (ranging in size from 0.3 to 290.4 ha) in an urban landscape, southwest China, among which habitat type composition and woody plant species composition varied significantly. Through 14 bird surveys conducted over six breeding seasons from 2017 to 2022, we recorded 70 breeding bird species (excluding birds recorded only once and fly-overs, such as raptors, swallows and swifts), with an average of 26 ± 10 (SD) species per patch. We found that patch area had significant direct and indirect effects on bird richness, with the indirect effects mediated by habitat richness (i.e., the number of habitat types). Isolation (measured as the distance to the nearest patch), perimeter to area ratio (PAR), and woody plant richness did not significantly predict variation in bird richness. Furthermore, none of these factors significantly sorted bird species based on their functional traits. However, the overall makeup of bird assemblages was significantly associated with the specific habitat types and woody plant species present in the patches. The results suggest that neither the island biogeography theory nor the habitat diversity hypothesis can fully explain the impacts of habitat fragmentation on bird richness in our study system, with their roles primarily being linked to patch area. The findings that habitat and plant compositions were the major drivers of variation in bird assemblage composition offer valuable insights into urban planning and green initiatives. Conservation efforts should focus not only on preserving large areas, but also on preventing urban monocultures by promoting diverse habitats within those areas, contributing to the persistence of meta-communities.

The superhydrophobic scallop-like Cu6Sn5 micro/nano structure were successfully constructed on pure copper substrate by heat-induced Cu/Sn interfacial metallurgical reaction and simple chemical modification process. The microstructure, chemical composition and corrosion resistance of as-prepared samples were characterized by field emission scanning electron microscopy and X-ray photoelectron spectroscopy, etc. The results show that the averaged shear resistance strength between micro Cu6Sn5 and Cu substrate is higher than 40 MPa. After modified with myristic acid and Cu2+, copper myristate with low surface energy is formed on the armor Cu6Sn5 surface. The wetting angle of water droplets on as-modified surface is higher than 150° and its rolling angle is 7.2°. Compared with pure copper, the self corrosion current density of the samples modified by copper myristate in 3.5%NaCl(mass fraction) solution is about 1/10 of that of the samples before modification,showing better corrosion resistance. Based on the metallurgical bonding mechanism between intermetallic compounds and metal matrix, the armor formation strategy of metal materials in micro-scale by heat-induced interfacial reaction is proposed, which can successfully solve the open and key scientific problem of low mechanical stability for artificial superhydrophobic interface.

An optical camera communication (OCC) is a special type of a visible light communication that uses a complementary metal-oxide semiconductor as a receiver. However, it is difficult to apply a high-order modulation scheme to such communications because of strong intersymbol interference. In this paper, we propose and demonstrate an OCC system using an 8-color color-shift keying scheme. We used an RGB-based LED light panel as a transmitter and analyzed the properties of the rolling shutter. We discuss the demodulation process and perform bit error rate (BER) tests at different ambient illuminances and sampling positions. A net data rate of 8.64 kbps and a pixel efficiency of 3.75 pixels per bit were achieved while keeping the BER below 3.8E-3, which meets the FEC's 7% forward error correction requirement. In addition, the system shows good robustness for indoor applications.

The optical properties of electrochromic materials can change reversibly under an applied voltage. Tungsten oxide has been widely used in various fields because of its excellent electrochromic efficiency. The electrochromic films produced by W _18 O _49 nanowires and WO _3 have excellent performance. Compared with WO _3 film, the porous structure of the nanowires can make ions rapidly diffuse, provide a larger surface area for the charge transfer reaction, promote electrolyte penetration, and effectively improve the electrochromic efficiency. In this paper, a kind of electrochromic tungsten oxide thin film combining W _18 O _49 nanowires and WO _3 was prepared by combining a hydrothermal method and a tungstic acid method. The electrochromic performance of the film was improved considerably by combining the two kinds of thin films. The results show that the optical modulation amplitude is close to ideal (92.5%) and has a fast colour fading (colour 1.7 s and colour fading 1.3 s) effect, a good cycle stability, which is much better than those of the WO _3 and W _18 O _49 films. Using lithium perchlorate and PC as raw materials and polyurethane as a photocuring agent, a solid-state electrochromic device based on a tungsten oxide composite film was fabricated by capillarity. The colouring time of the device is 2 s, the fading time is 1 s, and the optical modulation amplitude is 85%.

The objective of this paper is to predict the noise radiated from submarine propellers with different control surface types (the cross- and X-type). When the propellers are free from cavitation, such as those of submarines at a diving depth, the radiated noise dominate, due to unsteady propeller forces. A well-known submarine model (DARPA SUBOFF) is taken as the computing sample. Simulations for hydrodynamics, including stern wakes and unsteady propeller forces, are carried out by using CFD (Computational Fluid Dynamics) technology, and the results are compared with the experimental data. The accuracy of the predicted noise depends on the CFD results. Comparisons between the CFD results and the experimental data are in good agreement. The CFD results are treated as dipole strengths in the linear wave theory to predict the radiated noise caused by the unsteady forces of the propeller. It is found that, when the control surface is of the X-type, the propeller inflow is more uniform, and the radiated noise can be decreased by about 5 dB compared to the cruciform control surface. [ABSTRACT FROM AUTHOR]

In order to improve its water resistance and compatibility with polymer matrix, ammonium polyphosphate (APP) is modified with melamine‐trimesic acid (MEL‐TA) aggregates by supramolecular self‐assembly technology. Chemical structure and morphology of APP@MEL‐TA are investigated by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM), respectively. Intumescent flame retardant system of APP@MEL‐TA and charring‐foaming agent is introduced into polypropylene (PP) matrix. The flammability and combustion behavior of PP composites are investigated by limiting oxygen index (LOI), UL‐94 vertical burning, and cone calorimetry tests. In terms of LOI values and cone combustion results, APP@MEL‐TA performs better than pristine APP. Char residue of PP composites is investigated by SEM and Raman spectra. Flame retardant mechanisms are proposed based on thermal decomposition, combustion results, and analysis on char residue. [ABSTRACT FROM AUTHOR]

Piperazine cyanurate (PCA) is designed and synthesized via hydrogen‐bonding self‐assembly reactions between piperazine and cyanuric acid. Chemical structure and morphology of PCA are investigated by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The prepared PCA is combined with ammonium polyphosphate (APP) to prepare flame‐retardant polypropylene (PP) composites. Thermostability, flammability, and combustion characteristics of PP composites are analyzed. The maximum thermal decomposition rate of flame‐retarded PP composites has an apparent reduction compared with that of pure PP, and obvious char is left for this intumescent flame retardant (IFR) system of APP and PCA. A high limiting oxygen index value and UL‐94 V‐0 rating are achieved with addition of APP and PCA. In cone calorimetry test, heat and smoke releases of PP are significantly decreased by this IFR system. Gaseous decomposition products during the thermal decomposition of flame‐retardant composites are studied. Chemical structure and morphology of char residues are analyzed. The results illustrate that APP and PCA have a superb synergistic action in the aspect of improvement in fire safety of PP. A possible flame‐retardant mechanism is concluded to reveal the synergism between APP and PCA. [ABSTRACT FROM AUTHOR]

The identification of hydrogen in a range of lunar samples and the similarity of its abundance and isotopic composition with terrestrial values suggest that water could have been present in the Moon since its formation. To quantify the effect of water on early lunar differentiation, we present new analyses of a high‐pressure, high‐temperature experimental study designed to model the mineralogical and geochemical evolution of the solidification material equivalent to 700 km deep lunar magma oceans first reported in Lin et al. (2017a). We also performed additional experiments to better quantify water contents in the run products. Water contents in the melt phases in hydrous run products spanning a range of crystallization steps were quantified directly using a secondary ion mass spectrometry (SIMS). Results suggest that a significant but constant proportion (68 ± 5%) of the hydrogen originally added to the experiments was lost from the starting material independent of run conditions and run duration. The volume of plagioclase formed during our crystallization experiments can be combined with the measured water contents and the observed crustal thickness on the Moon to provide an updated lunar interior hygrometer. Our data suggest that at least 45–354 ppm H2O equivalent was present in the Moon at the time of crust formation. These estimates confirm the inference of Lin et al. (2017a) that the Moon was wet during its magma ocean stage, with corrected absolute water contents now comparable to estimates derived from the water content in a range of lunar samples. [ABSTRACT FROM AUTHOR]

γ‐Al2O3 nanoflakes are decorated on the surface of graphene nanosheets by hydrothermal method. The chemical structures, composition, and morphology of the graphene nanohybrid are characterized. Alumina nanoflake‐coated graphene nanohybrid is incorporated into polypropylene (PP) matrix by master batch‐based melt mixing method. The effects of alumina‐graphene nanohybrid on the thermal stability and combustion behavior of PP are investigated. More char residue is left for PP composite containing alumina‐graphene nanohybrid. Peak heat release rate of pure PP is greatly decreased by this nanohybrid, corresponding to 30.6% reduction. Fire safety of PP is considerably enhanced. Flame retardant mechanisms are concluded based on the combustion results and char analysis. The barrier effect of graphene and catalytic charring actions of γ‐Al2O3 nanoflakes make the contribution to the enhanced flame retardant properties. [ABSTRACT FROM AUTHOR]

In recent years, paper-based point-of-care testing (POCT) has been widely used in medical diagnostics, food safety and environmental monitoring. However, a high-cost, time-consuming and equipment-dependent sample pretreatment technique is generally required for raw sample processing, which are impractical for low-resource and disease-endemic areas. Therefore, there is an escalating demand for a cost-effective, simple and portable pretreatment technique, to be coupled with the commonly used paper-based assay (e.g. lateral flow assay) in POCT. In this review, we focus on the importance of using paper as a platform for sample pretreatment. We firstly discuss the beneficial use of paper for sample pretreatment, including sample collection and storage, separation, extraction, and concentration. We highlight the working principle and fabrication of each sample pretreatment device, the existing challenges and the future perspectives for developing paper-based sample pretreatment technique. [ABSTRACT FROM PUBLISHER]

The flue gas of boiler contains large amount of waste latent heat, and traditional heat recovery device is difficult to recover the latent heat due to the limitation of the specific heat of supply air. A deep heat recovery device between flue gas and supply air of gas-fired boiler is proposed in the paper, and the thermodynamic model is established to calculate its performance. The energy efficiency of gas-fired boiler with the device is compared with other systems. The result shows that the boiler efficiency with new heat recovery device is 5% and 13% higher than that of condensing boiler and boiler without heat recovery system, respectively. When the ambient temperature is higher, the energy efficiency is closer to the boiler with absorption heat pump for heat recovery, and the initial investment is lower. Therefore, both the energy efficiency and economy of this system is acceptable. [ABSTRACT FROM AUTHOR]

• The Sm-Nd isotopic compositions of apatite in MRB were analyzed in situ. • A Sm-Nd isochron age of 1490±480 Ma was determined for apatite in MRB, different from bulk-rock age. • Pyroxene, not apatite, is the major REE carrier in MRB. • The hydrothermal fluids could have derived from an enriched reservoir in the Martian crust. The observations of Martian orbiters and rovers have suggested that there were fluids on the surface of early Mars. However, the geochemical properties of those fluids are unclear. The Martian regolith breccia meteorites (MRB), the source materials of which are thought to have formed at 4.4 Ga, may have recorded interactions with fluids on Mars. Here, we have analyzed the in situ Sm-Nd isotopic compositions and trace element contents of apatite in MRB and have obtained a Sm-Nd isochron age of 1490±480 Ma. This young age indicates that the MRB apatites were altered by fluids and have exchanged trace elements with fluids. The very negative initial ε 143 Nd, combined with the previously reported positive δ D and δ 37 Cl in the MRB apatites, indicate that Martian fluids originated from a geochemically enriched reservoir in the crust. The large ranges of rare earth element abundance (ΣREE) and of the chondrite normalized ratio of La and Yb [(La/Yb) N ] indicate the chemical complexity of the fluids that interacted with the apatites in the MRB. The apatite REE compositions were used to further determine the pH values of Martian fluids equilibrated with the MRB apatites, which varied from ∼3 to ∼8. The apatite X-site Cl contents indicate that the Cl contents in Martian fluids in equilibrium with the MRB apatites at 400 °C and 1 bar could be up to 1857 ppm, within the range of terrestrial hydrothermal fluids. Combined with previously reported geochemical data from Martian meteorites, our study suggests that fluids may have been present throughout the early geological history of Mars. [ABSTRACT FROM AUTHOR]

• Experiments on the effect of supply air humidification on the energy and emission performance of domestic condensing boiler is undertaken. • Supply air humidification is beneficial for improving boiler efficiency, which is higher when the humidity of supply air is larger. • More latent heat can be recovered in the condensing heat exchange process of condensing boiler by supply air humidification. The traditional coal-fired boiler used for heating has a low efficiency and emits large amounts of pollutants. Thus, the use of natural-gas-fired boilers has become a popular method for heating all over the world owing to their cleanliness and high efficiency. Condensing domestic gas boilers have higher thermal efficiency than traditional boilers. However, they waste a large amount of heat. Supply-air humidification provides a beneficial effect on the efficiency of heat recovery, but the effects of supply-air humidification on the thermal performance of combustion and the amount of heat recovered from the latent heat remain unclear. Moreover, the effect of air humidification on pollutant emission must be further investigated. In this study, an experiment was conducted to investigate the effects of supply-air humidification on the thermal efficiency and emissions of a domestic boiler. The results indicated that supply-air humidification is beneficial for the improvement of the overall boiler efficiency. The maximum improvements in the boiler efficiency were 3.7% and 3.8% when the excess-air ratios were 1.3 and 1.1, respectively. Supply-air humidification had a significant effect on the condensing heat-exchange process. The maximum increments of the condensed water were 20.2% and 23.47% when the excess-air ratios were 1.3 and 1.1, respectively. When the excess-air ratio was 1.3 and the temperature and relative humidity of the supply air were 41.22 °C and 12.06%, respectively, almost half of the latent heat from the flue gas was recovered. Supply-air humidification reduced the concentration of NO x to a value within the emission limit. However, the amount of humidification needs to be controlled within a reasonable range to avoid massive generation of CO. [ABSTRACT FROM AUTHOR]