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The urban heat island effect is a typical feature of urban climates. Problems associated with urban heat islands include an increase in energy consumption and health issues resulting from a reduction in thermal comfort. The method of constructing a heat island network, which helps identify and analyze urban heat island phenomena, has become a focus of research in areas such as the effect of urban greening on the heat island effect. Considering this, Landsat remote sensing images from Tiantai County, Taizhou City, were used to identify and analyze the distribution characteristics of heat island patches in Tiantai County as a whole, using morphological spatial pattern analysis (MSPA) combined with the model of minimum cumulative resistance (MCR). Simultaneously, based on the local climate zones theory, the resistance value was calculated to construct the Tiantai County heat island network, and the following conclusions were formed after analyzing the results: (1) The final constructed heat island network consists of 20 important heat island sources, 60 important heat island corridors, and 130 general heat island corridors. (2) The important heat-island-source land matrix consists primarily of an impermeable surface, bare soil, and sand. Important heat island corridors are mostly found in the impermeable surface area. (3) According to calculations, dense trees have a resistance value of 100. Water bodies and scattered trees have resistance values of 10 and 5, respectively. They all have a blocking effect on the heat island. [ABSTRACT FROM AUTHOR]

To meet the demands for flexible electromagnetic interference (EMI) shielding materials, a type of conductive fabric is prepared by generating three-dimensional (3D) porous laser-induced graphene (LIG) in situ on the surface of the aramid fabric (AF) and then electroless plating copper. After LIG treatment, the porous AF demonstrates admirable conductivity due to the generation of graphene. The superior surface resistance of the conductive fabric can reach 1.57 Ω/sq after copper deposition, and the average EMI shielding effectiveness (SE) can reach 34.3 dB in a frequency range of 8.2 to 12.4 GHz, with the EMW absorption accounting for about 80%. The proposed technology provides a new idea for preparation of flexible EMI shielding materials. [ABSTRACT FROM AUTHOR]

Escherichia coli (E. coli) can be transmitted from dogs to surfaces through direct exposure to dog faeces, pus, and urine; alternatively, it can live in the environment for a short period. We aimed to determine the prevalence and antibiotic resistance profile of E. coli from dogs and environmental surfaces of animal clinics in Phnom Penh, Cambodia. We swabbed twenty-four samples from dogs (18 faeces and 6 pus) and twenty-three from environmental surfaces (8 cage-floors, 7 cage-walls, 1 feeding-plate, and 7 treatment-tables) at animal clinics. The bacterial culture method was used to isolate E. coli from both dog and environmental surface samples. An antibiogram of the isolates was tested using the disk diffusion method with six antibiotics (amoxicillin, ampicillin, ceftriaxone, gentamycin, levofloxacin, and tetracycline), following the standard of the Clinical and Laboratory Standard Institute. The results showed that E. coli was present in approximately 54% of dog samples and 22% of environmental surface samples. The E. coli isolates from dog samples showed high resistance to amoxicillin, ampicillin, and tetracycline (54%) and lower resistance to ceftriaxone, gentamycin (27%), and levofloxacin (8%). E. coli isolates from environmental surfaces demonstrated high resistance to amoxicillin, ampicillin, ceftriaxone, and tetracycline (80%-100%), and lower resistance to gentamicin and levofloxacin (60%). In conclusion, E. coli was found in both dogs and veterinary clinic surfaces and exhibited resistance to numerous antibiotics. This study suggests that further research is necessary to identify the specific genes responsible for the antibiotic resistance of E. coli found in dogs, on clinic surfaces, as well as in humans -- including clinic technicians and dog owners -- in order to better understand how this resistance is affected by the transmission of E. coli between different carriers. [ABSTRACT FROM AUTHOR]

An innovative application of the fiber reinforced engineered cementitious composite (ECC) in thermal insulation wall is presented in this paper. Special focuses are paid for the purpose of eliminating bond failure between the structural layer, thermal insulation layer and surface protective layer, and enhancing cracking resistance of the surface protective layer. ECC with characteristics of low drying shrinkage (LSECC), strain-hardening and multiple cracking was used as surface protective material in the wall. The test results show that uniformly distributed steel wires crossing the thermal insulation layer at an inclination angle to the direction of horizontal direction of the wall and embedded in the structural concrete layer with certain length can provide sufficient bond strength of structural layer, thermal insulation layer and surface protective layer. Tensile test results on LSECC used in the surface protective layer of the wall show that LSECC can provide sufficient tensile strain capacity to adsorb the deformation induced by temperature change, material shrinkage and mechanical loads. Meanwhile, high crack opening control ability and fine crack opening is expected as well during service. [ABSTRACT FROM AUTHOR]

Context: Evaluating connectivity and identifying corridors for protection is a central challenge in applied ecology and conservation. Rigorous validation and comparison of how approaches perform in capturing biological processes is needed to guide research and conservation action. Objectives: We aim to compare the ability of connectivity surfaces optimised using home range and dispersal data to accurately capture lion movement during dispersal, using cost-distance and circuit theory approaches. Methods: We delineate periods of dispersal in African lions (Panthera leo) to obtain movement trajectories of dispersing individuals across the Kavango Zambezi Transfrontier Conservation Area, southern Africa. We use these trajectories to assess comparative measures of connectivity values at dispersal points across surfaces and the ability of models to discriminate between observed and randomised paths. Results: Encouragingly, results show that on average, all connectivity approaches and resistance surfaces used perform well in predicting movements of an independent set of dispersing lions. Cost-distance approaches were generally more sensitive to resistance input than circuit theory, but differences in performance measures between resistance inputs were small across both approaches. Conclusions: Findings suggest that home range data can be used to generate resistance surfaces for connectivity maps in this system, with independent dispersal data providing a promising approach to thresholding what is considered as "connected" when delineating corridors. Most dispersers traversed through landscapes that had minimal human settlement and are likely highly connected by dispersal. Research into limiting factors and dispersal abilities will be critical to understanding how populations will respond to increasing habitat fragmentation and human expansion. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the quality control diagnostics of the used base layers on the interstation railway section Palárikovo - Nové Zámky, the article analyzes the achieved results of static load tests that were carried out on the plane of the sub-ballast upper surface. The verification of the values is based on the project documentation, in which, on the basis of a previously performed geotechnical survey, the designer proposed a suitable type of structural sub-ballast layers. The design of the structural sub-ballast layers reflects the expected deformation resistance of the subgrade surface, its water regime, the railway line characteristic (speed zone), the type of construction work (reconstruction) and also takes into account the principle of conservation of natural resources (recycling of recovered ballast bed material). [ABSTRACT FROM AUTHOR]

In this work, the effects of lyophobicity and lyophilicity of film-forming systems on the properties of thin nanostructured films was studied. Systematic series of experiments were carried out with lyophilic film-forming systems: SnCl4/EtOH, SnCl4/EtOH/NH4F, SnCl4/EtOH/NH4OH and lyophobic systems: SnO2/EtOH and SnO2/EtOH/NH4F. Film growth mechanisms are determined depending on the type of film-forming system. The surface of the films was studied using a scanning electron microscope and an optical microscope. The spectrophotometric method is used to study the transmission spectra and the extinction coefficient. The surface resistance of the films was determined using the four-probe method. The quality factor and specific conductivity of the films are calculated. It was found that the addition of a fluorinating agent (NH4F) to a film-forming system containing SnO2 in the form of a dispersed phase does not lead to an increase in the specific conductivity of the films. X-ray diffraction analysis proved the incorporation of fluorine ions into the structure of the film obtained from the SnCl4/EtOH/NH4F system by the presence of SnOF2 peaks. In films obtained from SnO2/EtOH/NH4F systems, there are no SnOF2 peaks. In this case, ammonium fluoride crystallizes as a separate phase and decomposes into volatile compounds. [ABSTRACT FROM AUTHOR]

A high battery temperature has been shown to be critical for lithium-ion batteries in terms of performance, degradation, and safety. Therefore, a precise knowledge of heat sources and sinks in the battery is essential. We have developed a thermal model for lithium-ion batteries, a model that includes terms not included before, namely, Peltier and Dufour heat effects. The model is derived using non-equilibrium thermodynamics for heterogeneous systems, the only theory which is able to describe in a systematic manner the coupling of heat, mass, and charge transport. The idea of this theory is to deal with surfaces as two-dimensional layers. All electrochemical processes in these layers are defined using excess variables, implying, for instance, that the surface has its own temperature. We show how the Peltier and Dufour heats affect a single cell and may produce an internal temperature rise of 8.5 K in a battery stack with 80 modules. The heat fluxes leaving the cell are also functions of these reversible heat effects. Most of the energy that is dissipated as heat occurs in the electrode surfaces and the electrolyte-filled separator. The analysis shows that better knowledge of experimental data on surface resistances, transport coefficients, and Dufour and Peltier heats is essential for further progress in thermal modeling of this important class of systems. [ABSTRACT FROM AUTHOR]

Reported data of measured slip lengths in nanostructures span several orders of magnitude, from a few nanometers to tens of micrometers. Small roughness on surfaces caused by structural defects or thermal fluctuations dramatically reduces slippage. Tiny bubbles entrapped on rough surfaces can also affect slippage. We used an asymptotic solution and a high density-ratio pseudopotential lattice Boltzmann model to systematically study the drag resistance of a rough surface with attached bubbles. As bubbles nucleate and grow, drag resistance is slightly reduced until the tri-phase contact line reaches the edges of roughness, where bubbles with small angles substantially reduce drag resistance. As bubbles grow to become a continuous gas layer on the surface, the drag resistance greatly decreases. However, the interface deformation from flat to curved shape greatly hinders liquid flow, and the vortex structures cause a wave-like fluctuation in the effective slip length. This finding sheds light on the controversies of reported large variations in the slip length of super-hydrophobic surfaces in nanostructures, e.g., carbon nanotubes. [ABSTRACT FROM AUTHOR]

Water collection via fiber-based coalescers shows promise in mitigating increasing water scarcity, and most studies usually focus on the water collection by accumulating water through successive coalescences of fog in the absence of condensation. Here, we report on non-uniform condensate morphologies observed during air–vapor mixture condensation on a cantilevered microfiber. Due to the competition between thermal conduction resistance within the fiber and condensation heat transfer resistance on the fiber surface, the vapor diffusive flux along the fiber varies accordingly, engendering three representative condensate morphologies. We systematically examine the effects of fiber length, diameter, and material (constantan, 316L steel, and alumel) on these condensate morphologies. Scaling analyses are also provided to reveal the underlying physics. Our experimental investigations and theoretical analyses reported in this work shed more light on air–vapor mixture condensation mechanisms that could pave the way to future condensation-associated applications. [ABSTRACT FROM AUTHOR]

Copyright of Elektronik Industrie is the property of Hüthig GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The resonant cavity method is a commonly used method for high-temperature testing of the complex permittivity of dielectric materials. When a resonant cavity is used for high-temperature testing, the microwave surface resistance of the cavity metal material will deteriorate due to factors such as oxidation reaction and thermal fatigue, resulting in a decrease in testing accuracy and repeatability. Therefore, when designing a high-temperature resonant cavity, the temperature response characteristics of the microwave surface resistance of the cavity metal material should be obtained in advance. In this paper, a high-temperature measurement method of microwave surface resistance of metal materials based on a separate cylindrical resonator is proposed, a mathematical model of microwave surface resistance inversion based on the resonator quality factor is established, and a high-temperature measurement system of microwave surface resistance is integrated. The reliability of the proposed method and system is verified through simulation and experiment. The measurement frequency covers 7-18 GHz, and the maximum test temperature reaches 500°C. Systematic error of microwave surface resistance measurement at room temperature is less than 3%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Herein, a facile synthesis of NVP with porous carbon skeleton is proposed. • The porous construction can alleviate the stress and strain caused by the current impact through deformation. • Ex-situ EIS reveals the carbon skeleton can reduce the surface resistance to promote the de-intercalation of Na+. • The ex-situ XPS spectra at different potentials confirms the stabilized existence of V O C bonds. • The modified PC-NVP releases superior sodium storage property. Low electronic conductivity and poor properties at high rate have hindered the application of Na 3 V 2 (PO 4) 3 (NVP). Herein, a facile synthesis of NVP with porous carbon skeleton is proposed. Specifically, Na 2 CO 3 and glucose, acting as hard templates, are introduced to the precursors after initial firing stage, and Na 2 CO 3 particles are removed by flushing after the final heatment. Due to the thermal conductivity of Na 2 CO 3 , the secondary addition of glucose can generate distinctive graphitized porous carbon skeleton, which bonds well with the amorphous carbon coating to construct stable and conductive network. The porous construction can alleviate the stress and strain caused by the current impact through deformation. Furthermore, ex-situ EIS reveals the highly conductive carbon skeleton can significantly reduce the surface resistance and result in an increase of effective voltage to promote the de-intercalation of Na+. Moreover, the ex-situ X-ray photoelectron spectroscopy (XPS) at different potentials confirms the stabilized existence of V O C bonds. Benefiting from the unique carbon skeleton, the PC-NVP releases capacity of 116.9 mAh g−1 at 0.1C. Even at 120C, PC-NVP still exhibits a high capacity of 84.7 mAh g−1, retaining a value of 41.3 mAh g−1 after 16,000 cycles, corresponding to a low decay rate of 0.0032% per cycle. [ABSTRACT FROM AUTHOR]

The development of new photoanode materials for hydrogen production and water treatment is in full progress. In this context, hybrid TiO2-Co3O4/Co(OH)2 photoanodes prepared using the sol–gel method using biosurfactants are currently being developed by our group. The combination of TiO2 with a cobalt-based compound significantly enhances the visible absorption and electrochemical performance of thin films, which is mainly due to an increase in the specific surface area and a decrease in the charge transfer resistance on the surface of the thin films. The formation of these composites allows for a 30-fold increase in the current density when compared to cobalt-free materials, with the best TiO2-CoN0.5 sample achieving a current of 1.570 mA.cm−2 and a theoretical H2 production rate of 0.3 µmol.min−1.cm−2 under xenon illumination. [ABSTRACT FROM AUTHOR]

Super saturation of inversely soluble salts in the phosphoric acid concentration process, like calcium sulfate, promotes fouling on the heat exchanger walls. This phenomenon leads to reduce the efficiency of such equipment and their continuous operation and increase energy losses. The present work aimed at studying the effect of the deposit of calcium sulfate on the fouling resistance on a heated walls. The fouling resistance was determined based on the operating data collected from the phosphoric acid concentration loop of a cross flow heat exchanger. X-ray diffraction analysis method was used to determine the crystal form of calcium sulfate. In addition, this paper aimed at modeling the fouling resistance with experimental data under various operating conditions using response surface methodology (RSM) in order to studying the interactive effects of operating parameters on fouling. Results show that the anhydrite (CaSO4) is the main crystal form of fouling formed on heat exchanger walls indicating that the crystallization fouling dominates the fouling process. The volume flow affects the fouling resistance especially at high wall temperature by increasing the fouling resistance with decreasing volume flow. The fluid temperatures are found to enhance significantly the fouling resistance on the surface. The determination coefficient of the proposed RSM model in the studied case was found to be 99.54%, which is considered to be satisfactory. [ABSTRACT FROM AUTHOR]

Workbench-size particle accelerators, enabled by Nb3Sn-based superconducting radio-frequency (SRF) cavities, hold the potential of driving scientific discovery by offering a widely accessible and affordable source of high-energy electrons and x-rays. Thin-film Nb3Sn RF superconductors with high quality factors, high operation temperatures, and high-field potentials are critical for these devices. However, surface roughness, non-stoichiometry, and impurities in Nb3Sn deposited by conventional Sn-vapor diffusion prevent them from reaching their theoretical capabilities. Here we demonstrate a seed-free electrochemical synthesis that pushes the limit of chemical and physical properties in Nb3Sn. Utilization of electrochemical Sn pre-deposits reduces the roughness of converted Nb3Sn by five times compared to typical vapor-diffused Nb3Sn. Quantitative mappings using chemical and atomic probes confirm improved stoichiometry and minimized impurity concentrations in electrochemically synthesized Nb3Sn. We have successfully applied this Nb3Sn to the large-scale 1.3 GHz SRF cavity and demonstrated ultra-low BCS surface resistances at multiple operation temperatures, notably lower than vapor-diffused cavities. Our smooth, homogeneous, high-purity Nb3Sn provides the route toward high efficiency and high fields for SRF applications under helium-free cryogenic operations. [ABSTRACT FROM AUTHOR]

The design of a glazing package containing heating glass can make a window a radiator simultaneously. For such bulky glass to act as an effective radiator simultaneously, it should be possible to provide a constant temperature over the entire surface. The continuous surface temperature of the glass depends on the uniformity of the surface resistance of the resistive layer. This paper will demonstrate the testing of heating glass parameters using a specialised apparatus. The research will mainly focus on measuring the value and distribution of the surface resistance of the transparent heating layer. A thermographic study will verify the results. As the heating glass will be subjected to a toughening process, the effect of the toughening process parameters on the degradation of the transparent heating film will be investigated. [ABSTRACT FROM AUTHOR]

The purpose of this research is to examine the effect of strontium aluminate (SrAl2O4) in copper samples on phosphorescence and tarnish resistance properties. The samples were fabricated by powder metallurgy using the compression moulding technique and then sintered in argon atmosphere. Phosphorescence, hardness, microstructure and tarnish resistance were studied. In the process of the compression moulding, the samples contain 100, 90, 80 and 70 percent of copper powder, by weight, with the addition of 0, 10, 20 and 30 percent of strontium aluminate, by weight, respectively. Polyvinyl alcohol (PVA) was used as a binder and mixed with copper and strontium aluminate powder to produce the green specimens using a hydraulic machine. Then, the green samples were sintered at 900 °C for one hour. After sintering, PVA was eliminated and the samples became denser. It was found that the hardness of the sample without strontium aluminate (30.5 HV) is higher than that of the sample with 10% of strontium aluminate addition (12.84 HV). Furthermore, copper samples containing strontium aluminate were fluorescent under ultraviolet at 517 nm. The sample with the largest amount of strontium aluminate (70Cu-30SrAl2O4) has higher phosphorescence than 90Cu-10SrAl2O4. In sulphur atmosphere, the tarnish resistance was found to be improved when strontium aluminate was added into copper. The colour difference (DE*) of 100Cu, which has no strontium aluminate, was 6.42 and higher than that of 90Cu-10SrAl2O4 (DE*= 3.5), 80Cu-20SrAl2O4 (DE*= 1.37), and 70Cu-30SrAl2O4 (DE*= 0.49), when testing in sulphur atmosphere for 30 min. 70Cu-30SrAl2O4, containing the highest amount of strontium aluminate, has the least colour changing on its surface resulting in the resistance in tarnishing. [ABSTRACT FROM AUTHOR]

Experimental results indicate that wire mesh casing treatment (WMCT) enhances the stability of low-speed compressors with little reduction in efficiency. The flow resistance on the surface of the grooves, which are formed by the wire mesh, provides a new variable for the design of WMCT. This paper investigates the stability improvement induced by three different meshes through experiments and steady numerical simulations. A stability prediction model incorporating the effect of WMCT is developed to assess the stability of the steady flow field, and the results show that the predicted stall points of the compressor are close to those of the experimental data. The stability analysis model has a well-defined theoretical foundation in which the meridional flow field of the compressor is considered as the basic flow and the blade is replaced with a body force. This formulation enables fast and accurate stability assessments of compressors incorporating WMCT during the design process. Finally, based on the influence of the different meshes on the steady flow field, the stability-enhancing mechanism of WMCT is analyzed in terms of flow field details and macroscopic physical quantities. WMCT improves the flow around the tip region, shifting the tip blade loading in the aft direction and reducing the tip leakage flow. Macroscopically, the installation of WMCT makes the flow structure in the tip region less sensitive to changes in the compressor operating conditions. [ABSTRACT FROM AUTHOR]

Surface carbonization, or charring, of wooden exterior cladding boards is a modification method that creates a fully organic barrier layer in resemblance to a coating. The process effectively degrades the wood and transforms it into a carbonaceous residue that protects the underlying unmodified wood from environmental stresses. The surface quality of wood modified in this manner is a combination of several factors and depends on the manufacturing method and wood species. To assess the quality of spruce and birch modified with contact and flame charring techniques, several experiments were set up from the nanoscale to macroscopic evaluation of surface resistance to different stresses. The changes in elemental composition are scaled with the modification severity with little differences between wood species. The carbon structures analyzed by high-resolution transmission electron microscopy (HR-TEM) were found to be amorphous, but the electron energy-loss spectroscopy (EELS) revealed higher ordering with what is assumed to be random graphitic stacking of carbon sheets. These carbon–carbon bonds are stable, so a higher ordering is hypothesized to induce improved resistance to exterior stresses. The scanning electron microscopy (SEM) revealed a clear difference between contact-charred and flame-charred woods. The selected contact charring temperature was not high enough to induce the transformation of cell walls from anisotropic into an isotropic material but provided other benefits such as a relatively crack-free, smooth and scratch resistant surface. Surface roughness was able to adequately predict the surface quality of the contact-charred samples, and scratch tests were found to be suitable for evaluating the mechanical stress resistance of the surface instead of abrasion. In terms of overall quality, birch instead of spruce was concluded to better respond to both charring methods, although contact charring eliminates some species-specific characteristics, resulting in more homogeneous surfaces. [ABSTRACT FROM AUTHOR]

The aquatic environment has been recognized as a source of antibiotic resistance (AR) that factors into the One Health approach to combat AR. To provide much needed data on AR in the environment, a comprehensive survey of antibiotic-resistant bacteria (ARB), antibiotic resistance genes (ARGs), and antibiotic residues was conducted in a mixed-use watershed and wastewater treatment plants (WWTPs) within the watershed to evaluate these contaminants in surface water. A culture-based approach was used to determine prevalence and diversity of ARB in surface water. Low levels of AR Salmonella (9.6%) and Escherichia coli (6.5%) were detected, while all Enterococcus were resistant to at least one tested antibiotic. Fewer than 20% of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (17.3%) and carbapenem-resistant Enterobacteriaceae (CRE) (7.7%) were recovered. Six ARGs were detected using qPCR, primarily the erythromycin-resistance gene, ermB. Of the 26 antibiotics measured, almost all water samples (98.7%) had detectable levels of antibiotics. Analysis of wastewater samples from three WWTPs showed that WWTPs did not completely remove AR contaminants. ARGs and antibiotics were detected in all the WWTP effluent discharges, indicating that WWTPs are the source of AR contaminants in receiving water. However, no significant difference in ARGs and antibiotics between the upstream and downstream water suggests that there are other sources of AR contamination. The widespread occurrence and abundance of medically important antibiotics, bacteria resistant to antibiotics used for human and veterinary purposes, and the genes associated with resistance to these antibiotics, may potentially pose risks to the local populations exposed to these water sources. [ABSTRACT FROM AUTHOR]

Accurate and timely observations of individual‐scale transpiration are critical for predicting ecosystem responses to climate change. Existing remote sensing methods for measuring transpiration lack the spatial resolution needed to resolve individual plants, and their sources of uncertainty are not well‐constrained. We present two novel approaches for independently quantifying fine‐scale transpiration using thermal imagery and a suite of environmental sensors mounted on an unmanned aerial vehicle (UAV) platform. The first is a surface energy balance (SEB) approach designed for fine‐scale thermal imagery; the second uses profiles of air temperature (Ta) and humidity (hr) to calculate transpiration from the Bowen Ratio. Both approaches derive the energy equivalent of transpiration, latent heat flux (λE), solely using data acquired from the UAV. We compare the two approaches and their sources of uncertainty using data from several flights at a grassland eddy covariance site in 2021 and 2022 and using typical diurnal conditions to evaluate the uncertainty of λE estimates for each approach. The SEB approach generated independent, UAV‐based estimates of λE within ∼20% of eddy covariance measurements and was most sensitive to surface temperature and resistance to heat transfer. λE calculated from the Bowen Ratio approach was ∼30% higher than tower values due to inaccuracies in Ta and hr, the main sources of uncertainty in this approach. The Bowen Ratio approach has a lower overall potential uncertainty, indicating its potential for improvement over the SEB approach. Our results are the first physically‐based observations of transpiration derived solely from a UAV platform, with no ancillary data inputs. Key Points: Integrating characterization of atmospheric profiles on unmanned aerial vehicle platforms with thermal imagery enables independent plant water use observationsThe ability to capture atmospheric profiles of heat and humidity enables a theoretical approach that minimizes uncertainty in Evapotranspiration estimatesAtmospheric profile approaches have the potential to substantially improve observations of individual plant water use [ABSTRACT FROM AUTHOR]

The pressure-sensing mechanisms of conductive elastomers, such as conductive networks, and tunneling effects within them have been extensively studied. However, it has become apparent that external pressure can significantly impact the contact area of polymeric materials. In this study, we will employ a commercially available conductive elastomer to investigate changes in resistance and contact surface under external pressure. Resistance measurements will be taken with and without applying conductive grease to the surface of the elastomer. This allows us to observe changes in resistance values associated with pressure variations. Furthermore, as pressure is applied to the conductive elastomer, the contact area ratio increases. Such an increase in the contact area and its correlation to changes in conductance values will be assessed. [ABSTRACT FROM AUTHOR]

Coin cells have been widely adopted for the evaluation of battery materials and chemistry. Herein, however, the coin cells are found unable to correctly reflect the fast‐charging capability of batteries. This is because, in the coin cells, the pressure between electrodes is provided by a wave spring while the wave spring cannot apply sufficient pressure to maintain the necessary electric contact for fast charging, leading to high polarization and resultant Li plating at the graphite anode. Testing on graphite/LiNi0.80Co0.10Mn0.10O2 coin cells shows that replacing the wave spring with a flat O‐ring washer dramatically stabilizes capacity retention in fast charging. Alternating current‐impedance analyses on the cells before and after 200 5 C‐charging cycles indicate that the cell with the O‐ring washer initially has a larger surface layer resistance, however, after fast‐charging test retained much smaller overall resistance compared with the cell using the wave spring. Visual observation of the cycled cell components reveals that the improvements are due to significantly reduced Li plating at the graphite anode, which is attributed to the appropriate pressure and the uniform distribution of the pressure applied by the flat O‐ring washer. [ABSTRACT FROM AUTHOR]

Context: Landscape genetics provides powerful tools to quantify the effects of landscape features on population connectivity, but robust results are imperative to inform conservation planning. Objectives: The robustness of landscape genetic inferences was assessed using the case of the northern crested newt (Triturus cristatus) in Luxembourg. Specifically, the effect of different study designs and genetic distance metrics was tested in terms of model convergence and misspecification rates (Type I error). Methods: The optimisation of resistance surfaces was performed in ResistanceGA, using individual- and population-based sampling designs and 16 genetic distance metrics inferred from 897 multilocus genotypes from 85 locations. Empirical results were complemented with simulations to assess Type I error rates and correlation between 'true' and optimised resistance surfaces. Results: Individual-based optimisations seemed prone to overfitting, with little convergence among empirical resistance surfaces from different sets of individuals. Simulations showed significant differences in performance among population genetic distance metrics. Linear topographical features exhibited higher Type I error rates (83.3%) than continuous features (44.9%), suggesting potential underestimation of road-induced fragmentation effects. Jost's D, F ST , and PCA axes 1–45 were the top three genetic distance metrics for recovering true resistance features. Topographic roughness consistently drove spatial genetic clustering of T. cristatus, but variability existed among conductivity maps derived from optimised resistance surfaces. Conclusions: These findings underscore the importance of carefully selecting genetic distance metrics and addressing potential sources of uncertainty in resistance surface optimisation. By doing so, we can enhance the effectiveness of conservation planning efforts for T. cristatus and species with similar ecological considerations. [ABSTRACT FROM AUTHOR]

The protection and decorative value of raw wood-based boards with various coatings can be enhanced during the service life of furniture using surface treatment techniques. In this study, selected transparent, pigmented polyurethane email finish and thin foils, commonly used in furniture, were used for surface treatments of medium-density fibreboards with a thickness of 18 mm. Water-borne finish with polyurethane–acrylate resin, solvent-borne finish with polyacrylate resin, and finish based on native oil and waxes, as well as pigmented polyurethane email finish, were used on veneered medium-density fibreboards. The thin foils (polyvinyl chloride, polyethylene terephthalate, and lacquered acryl film) were used for raw medium-density fibreboards. Several resistance surface properties were investigated. It was found that the hardness and resistance to impact were very much related to the interactions between the coating film or thin foil and the substrate. The type of surface finish had a substantial impact on the coating and foil's resistance qualities, such as resistance to mould and cold liquids. [ABSTRACT FROM AUTHOR]

Piezoelectric energy harvesters operate by converting mechanical vibrations or strains into electrical energy. From recent research, it is understood that the choice of coating material for piezoelectric energy harvesters is a critical consideration that impacts the device's performance, durability, and compatibility with the intended application. Selecting the right coating material involves balancing the electrical, mechanical, and environmental requirements to optimize energy conversion and reliability. There are methods like the thermocycling process that can provide an accelerated ageing of the energy harvester in order to conduct a reliability assessment. The thermocycling process was carried out for 450 h on six samples of piezoelectric cantilever-type energy harvesters made of copper–nickel- and aluminum-coated PVDF (Polyvinylidene fluoride) piezoelectric material. The effect of aluminum and copper–nickel coating on PVDF piezoelectric material before and after the aging process was studied. The numerical results of the generated output voltage, surface resistance, and capacitance values measured before and after the accelerated aging process are presented in this study. This work also discusses the structure of the developed energy harvester, thermocycling experiment setup, and methodology of conducting the ageing process. It aims to provide a conclusion on the suitability of the PVDF metal coating material, the type of conductive adhesive to be used in order to seal the PVDF material to the harvester core, improvements in the structural design and selection of materials to reduce mechanical fatigue and ensure even stress distribution, and minimizing points of stress concentration, to help mitigate piezoelectric material delamination risks. [ABSTRACT FROM AUTHOR]

The organic nature of composite insulators makes them vulnerable under various stress even though they offer many advantages compared to ceramic counterparts. This premature aging will create a major change in surface profile, variation in chemical bonding and hydrophobicity. Those factors will make the polymers lose their insulation property, resulting in an increase in leakage current, causing frequent flashover. This can ultimately make insulators of this type fail at normal operating voltage, causing disruption in power utilities, resulting in huge economic losses. So in this regard an attempt has been made by the author in the work to understand the chemical phenomena behind this premature natural aging. The various categories of insulators with profiles termed as virgin, 2 years aged, 3 years aged with bio growth, shrinked and flashover has been collected from the marine environment. Analysis of the insulators by Fourier transform infrared spectroscopy indicates that as the insulators age there will be serious decrease in aging resistance, degradation resistance and hydrophobic property. Shore A hardness indicates the surface becomes very hard with aging causing decrease in surface resistance. Water contact angle measurements indicate that material tends to become more hydrophilic. The silica oxidation, oligomer formation and shielding effect reduction are the main factors leading to the insulation failures of field aged insulators. This work will help power system engineers timely replace aged insulators of the type and prevent huge economic losses to the utility industry. [ABSTRACT FROM AUTHOR]

Feral pigs (Sus scrofa) are a destructive and widespread invasive pest in Australia. An understanding of feral pig movement is required to develop management strategies to control feral pigs in Australia. Because landscape structure can have a strong influence on animal movement, it is important to determine how landscape features facilitate or impede the movement of feral pigs. Consequently, we conducted a landscape genetic analysis of feral pig populations in the Herbert region of far north Queensland, Australia, to determine management units and provide recommendations to better inform feral pig population control strategies. Using microsatellite data obtained from 256 feral pig samples from 44 sites, we examined feral pig population structure at multiple spatial scales for univariate and multivariate landscape resistance surfaces to determine the optimal spatial scale and to identify which of the nine landscape features tested impede or facilitate feral pig gene flow. Only weak genetic structure was found among the 44 sampling sites, but major waterways were identified as a minor barrier to gene flow, and an isolation by distance model was supported. We also found that highways facilitated gene flow across the study area, and this suggests that they may act as movement corridors or indicate translocation of feral pigs. Additionally, incorporating a second spatial scale enhanced the ability of our landscape genetics analysis to detect the influence of landscape structure on gene flow. We identified three management units based on natural barriers to gene flow and future targeted control should be undertaken in these management units to deliver sustained reduction of feral pig populations in the Herbert region. This study demonstrates how a landscape genetic approach can be used to gain insight into the ecology of an invasive pest species and be used to develop population control strategies which utilise natural barriers to movement. [ABSTRACT FROM AUTHOR]

The thermodynamic characteristics of the electrochemical process in a solid oxide fuel cell (SOFC) are determined using a physical model that takes into account the internal reforming of methane. These characteristics can be a useful tool for studying the thermodynamic cycles of power plants without calculating the physical processes in the fuel cell. The initial data when using them are the load factor and the specific surface resistance of the membrane-electrode assembly. [ABSTRACT FROM AUTHOR]

Biocompatibility and tribological issues with 316L stainless steel (SS) biomaterials reduce their service life. A metallic substrate made of stainless steel 316L (SS) was employed, and after being subjected to a surface anodization process using sulfuric and nitric acids, it was coated with silver using a DC sputtering plasma method. The crystallinity, morphology, and microstructure of the coating have been investigated as well using structural characterization methods as XRD, FESEM, and EDS. To assess the coatings' qualitative adherence to the steel substrates, the coated substrates underwent the Rockwell - C indentation tests. An optical profilometer was used to measure the coatings' surface properties. Using potentio-dynamic polarization experiments, the corrosion resistance of coated and uncoated SS substrates was evaluated. The results show that the silver coating and anodized surface increase the resistance to corrosion behavior of SS. The silver coated SS and surfaces treated for corrosion both see a reduction in corrosion current density. These further demonstrate the potential for using surface-treated and silver-coated stainless steel as a surgical instrument to increase biocompatibility and resistance to corrosion. [ABSTRACT FROM AUTHOR]

The binary Zn-1wt.% X (X = Mg or Sr) alloys prepared by the application of mechanical alloying (MA) combined with powder metallurgy were modified by micro-arc oxidation (MAO) treatment in the 2 g/dm3 KOH aqueous solution at 200 V for 1 min for the formation of the ZnO layer. The Zn-alloys, obtained through the powder metallurgy method, are characterized by a dispersive microstructure that significantly improves its microhardness up to 90.5 HV0.3 for the Zn-1wt.%Mg sample after 24 h of MA. In the case of Zn-1Mg alloy after 24 h of mechanical alloying, Zn-1Mg alloy after 48 h of mechanical alloying, and Zn-1Sr alloy after 48 h of mechanical alloying, except for the main αZn phase, the traces of a second phase are noticed: MgZn2 and SrZn13. After the proposed MAO treatment, a zinc oxide (ZnO) layer on the zinc alloys was formed, allowing a significant improvement in the corrosion resistance and surface wetting properties. The potential of the modified ZnO layer is moved to more noble values in the case of MAO-treated samples α-Zn, Zn-1Mg (after 24 h of MA), and Zn-1Sr (after 48 h of MA). The obtained results show a good prospective potential of Zn-1wt.% X (X = Mg or Sr) binary alloys in the application of biodegradable materials. [ABSTRACT FROM AUTHOR]

The results of electron beam processing of Mn-Zn ferrite samples using pulsed and continuous electron beams in the fore-vacuum pressure range (10 Pa) are presented. We find that continuous electron beam processing leads to surface structuring of the ferrite, changes in elemental composition on the surface, and electrical property modification. The degree of ferrite parameter changes exhibits a threshold behavior. For surface processing temperatures below 900 °C, changes are barely noticeable, while for temperatures over 1100 °C the surface resistance decreases by more than an order of magnitude to values of less than 3 kOhm. Electron beam processing with millisecond pulse duration and pulse energy density exceeding 15 J/cm2 results in the formation of low zinc content melt islands, while the remaining surface area (outside the islands) elemental content and ferrite properties remain largely unchanged. The thickness of the modified layer depends on the processing mode and can be controlled over the range of 0.1–0.5 mm. Due to its low resistance, the modified layer can be utilized to enhance the RF-absorbing properties of the ferrite, which is important in the design of modern magnetic elements of electronic equipment. [ABSTRACT FROM AUTHOR]

This study aims to enhance the practical performance of PVDF/ZnO and PVDF/TiO2 composite coatings known for their distinctive properties. The coatings, applied through spray coating with PVDF and ZnO or TiO2 nanoparticles on glass, steel, and aluminum substrates, underwent a comprehensive evaluation. Surface wetting properties and morphology were respectively evaluated using a technique involving liquid droplets and an imaging method using high-energy electrons. Potentiodynamic polarization was used to compare corrosion resistance between coated and bare substrates. Nanoindentation was used to assess coating hardness, and bonding strength was subsequently quantified. The results revealed that PVDF/ZnO composite coatings had higher water contact angles (161 ± 5° to 138 ± 2°) and lower contact angle hysteresis (7 ± 2° to 2 ± 1°) compared to PVDF/TiO2 and PVDF coatings. Moreover, corrosion tests demonstrated superior protection for steel and aluminum surfaces coated with superhydrophobic PVDF/ZnO. Nanoindentation indicated enhanced mechanical properties with TiO2 nanoparticles, with adhesion results favoring TiO2 over ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

Objective: Wear and surface hardness of resin composites are of relevance from the clinical standpoint. With the incorporation of novel filler system, more studies need to be performed to investigate newly marketed resin composites. The objective of this study was to investigate the abrasive wear and surface hardness of dental restorative with different filler types. Methods: Nanohybrid filled Harmonize (HM) and Tetric N-Ceram (TNC), microhybrid filled Filtek Z250 (Z250), nanofilled Filtek Z350 (Z350) were included in the study. Twelve cylindrical resin composites specimens with 10 mm in diameter and 6 mm in thickness were prepared for abrasive wear test. Eight hundred cycles under 17 kg load were conducted for final wear by CW3-1 wear machine. The specimen was cleaned with an ultrasonic unit for 3 min followed with drying procedure. After measurement of weight loss and the density of specimens, the specimens were kept for measurement of surface hardness. Surface hardness was measured using a micro-hardness tester with a Vickers diamond indenter after polishing. Three specimens of each material were observed by scanning electron microscopy (SEM) after the abrasion to evaluate the morphology of the surface. Data were analyzed using one-way analysis of variance (ANOVA), followed by Tukey HSD test (α =.05). Results: Z250 performed the least volume wear loss (41.1 ± 2.1 mm3), as well as the hardest value (102.7 ± 2.9 HV). There was no significant difference with the volume wear loss (p = 1.000) and surface hardness (p = 0.874) of HM and TNC. SEM images of nanohybrid filled HM and TNC represented smoother surface compared with other types of resin composites. Conclusions: Microhybrid Z250 showed the highest wear resistance and surface hardness, nanofilled and nanohybrid resin composites may still face the insufficient of wear and surface hardness quality. [ABSTRACT FROM AUTHOR]

Reasonable planning of the limited land resources can promote the coordinated development of social economic and ecological protection. It is very important to optimize the rational distribution of land resources in the arid inland river basin because of the scarce land. In this paper, the GIS technologies of spatial analysis, conversion of land use, and its effects at small regional extent (CLUE-S) and minimum cumulative resistance (MCR) model were used to optimize the land allocation. The ecological security pattern (ESP) was constructed through using MCR model, which included ecological source and resistance surface. The dynamics of land use and spatial optimizing allocation of Shiyang River Basin in 2025 and 2030 was simulated under three different optimization scenarios including farmland protection scenario (FPS), free development scenario (FDS), and ecological security pattern scenario (ESPS). It was found that under ESPS, farmland was reduced, but woodland, grassland, and water body were increased significantly. Under FPS, land for construction was controlled effectively, a large part of homestead was converted into farmland, and the potential of unused land was developed vigorously. Furthermore, the current FDS and macro policy guidance should be comprehensively considered. The ESPS was more suitable for the scientific development of Shiyang River Basin on a long view. The combination of CLUE-S and MCR can effectively improve the optimization methods under ecological process and ecological resistance of landscape elements. [ABSTRACT FROM AUTHOR]

Emulsion polymerization was used to create composites of polyaniline‐amino‐carbon nanotubes (PANI‐A‐CNT). Fourier transform infrared spectroscopy (FT‐IR) was used to examine the chemical bonding properties of PANI and carbon nanotubes in composite materials. Transmission electron microscopy (TEM) was used to confirm that the PANI layer on the core‐shell structure of PANI‐A‐CNT material was nanoscale in size. In order to assess the impact of various carbon nanotube contents on the electrostatic and mechanical properties of the composites, pristine carbon nanotube/ABS (p‐CNT/ABS) and PANI‐A‐CNT/ABS composites were prepared. The mass fractions of PANI and CNT in PANI‐A‐CNT were 93.7 and 6.3 wt%, respectively, according to thermogravimetric analysis (TGA); hence, 4 wt% of PANI‐A‐CNT included 0.3 wt% CNT and 3.7 wt% PANI. The surface resistance test revealed that the PANI‐A‐CNT/ABS composite with 4 wt% PANI‐A‐CNT has a surface resistance of 108 Ω, which is one time less than the surface resistance of the p‐CNT/ABS composite with 4 wt% p‐CNT. Moreover, PANI‐A‐CNT/ABS composite (0–4 wt% PANI‐A‐CNT) has stronger tensile and impact properties than p‐CNT/ABS composite (0–4 wt% p‐CNT), expanding the range of applications for ABS resin. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to improve the dyeing effect of fast-growing fir wood dyed with reactive dyes. Design/methodology/approach: In this study, five factors including temperature, the dosage of dye accelerator, dyeing time, the dosage of fixing agent and fixing time were investigated. Then, the color difference and light resistance of the wood surface after dyeing were used as the evaluation indicators; the best dyeing process under the two indicators was obtained through the range analysis. Finally, the two indicators were considered comprehensively, and the fuzzy comprehensive evaluation method was used to obtain the best dyeing process under the comprehensive indicators. Findings: The results show that when the comprehensive index was used as the evaluation index, the optimal dyeing process for reactive red X-3B dyeing fast-growing fir veneer was that the dyeing temperature was 65°C; the amount of dye accelerator was 25 g L−1; the dyeing time was 2 h; the amount of fixing agent was 15 g L−1; and the fixing time was 35 min. Originality/value: The technique of wood dyeing is an important method to increase the value of wood products. When using different kinds of dyes or dyeing substrates for wood dyeing, the dyeing process is different. This study determined the best process for reactive dye dyeing of fast-growing fir veneer and provided a solution for improving the value of fast-growing fir wood. [ABSTRACT FROM AUTHOR]

;The modified graphene/bacterial cellulose composite conductive fiber membranes were prepared by three different process which are vacuum filtration-solution reduction vacuum filtration-steam reduction and reduction-vacuum filtration. Structure and performance of prepared fiber membranes were characterized by scanning electron microscopy ( SEM) X-ray difraction ( XRD) and Raman spectroscopy. The effects of three kinds of membrane preparation processes on the surface resistance of the composite conductive fiber films were discussed. The effect of the three process on the surface resistance of the conductive fiber membranes were investigated. The results showed that PNIPAM-rGO was able to bond with bacterial cellulose ( BC) in vacuum filtration-solution reduction process and vacuum filtration-steam reduction process while the bonding effect was poor in reduction-vacuum filtration process. Besides XRD spectroscopy confirmed that the presence of PNIPAM-rGO almost did not affects the structure of crystalline region of BC Raman spectroscopy better confirmed that PNIPAM-GO can be fully reduced to PNIPAM-rGO. By comparing the surface resistance of the conductive fiber membranes it was found that the best conductivity was achieved by the membrane making-vapor reduction method. [ABSTRACT FROM AUTHOR]

This research was conducted with the aim of investigating the effect of two-layers coating of nano-polyurethane and nano-clay on the mechanical and physical properties of packaging cardboard with brown layer. For this purpose, brown layer cardboard with the grammage of 127 grams/m2 was prepared and tested. The cardboard was first spray coated with nano-polyurethane. Then the surface of the spryed brown layer cardboard surface was covered with nano-clay to improve the performance of the coating material of the first treatment. Nano-clay coating was performed by a laboratory coating machine called barcoter. The coated cardboards were restrained and dried at room temperature for one day to stabilize the coating material on the surface. Then the samples were placed inside the freezer for 2 and 4 months and the properties were measured. The results showed that coating reduced water absorption. In the coated and frozen samples, an increase in thickness, smoothness of the surface and a decrease in water absorption and resistance properties were measured compared to control samples. Double coated samples showed very few porosity. The thickness of the coated samples, smoothness of the surface and tearing resistance in the machine cross direction of the double coated brown cardboard showed an increase of 13.7%, 75% and 3.8%, respectively, compared to the control sample. Water absorption, burst, tear and tensile strength in the machine direction,, tensile strength in the cross machine direction, resistance to ring crush test in the machine direction and resistance to ring crush test in the cross machine direction of the double-coated brown layer cardboard compared to the control sample, measured which showed 107.20, 1.5, 34.3, 25.4, 24.3, and 4.7 percent decrease respectively. [ABSTRACT FROM AUTHOR]

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Non‐water‐limited canopy resistance (rcs, also known as the bulk stomatal resistance or surface resistance) is a critical variable in estimating potential evapotranspiration (PET), which is widely used in ecohydrology related fields. However, quantifying rcs is a challenging work. Here we develop an approach for estimating rcs over the globe. Comparing results over the globe and across 10 ET data sets (used as inputs), which are based on diverse mechanisms and algorithms, we find that the approach can capture canopy resistance well (mean correlation of 0.84 ± 0.04, mean relative Root Mean Squared Error of 4.4% ± 1.0%, and mean relative Mean Absolute Error of 5.8% ± 1.4%), and the estimated rcs are very close to those estimated using another method (R2 = 0.92), which is based on a quite different hypothesis that is only suitable for saturated regions. Based on these, we find that the rcs shows an overall increasing trend (0.43 ± 0.13 s m−1 year−1) over the globe (at 77.6% ± 3.9% of the land grid cells) during 1982–2014, and the air temperature dominates the variabilities of rcs in regions with decreasing rcs (mean relative contribution of 57.9% ± 11.4%), while air CO2 concentration controls the changes in rcs in regions with increasing rcs (mean relative contribution of 47.3% ± 8.0%). Moreover, we also find that the traditional PET estimator explicitly overestimates the increasing trends in PET, and tends to overestimate (underestimate) the increasing (decreasing) trends in regions with increasing (decreasing) PET. These findings can improve our knowledge on the complex water‐vegetation‐environment interactions and would be helpful for developing more accurate models for quantifying the impacts of global change on water resources. Key Points: An approach is developed to estimate the non‐water‐limited canopy resistance (rcs) over the globeChanges in Ta ([CO2]) dominate the variabilities of rcs in regions with decreasing (increasing) rcsTraditional potential evapotranspiration (PET) overestimates (underestimates) the increasing (decreasing) PET trends in regions with increasing (decreasing) PET [ABSTRACT FROM AUTHOR]

The aerodynamic resistance at the snow surface (ras) has an influence on the snowpack energy balance. However, there are no widely accepted approaches for parameterizing ras in forested regions. In this study, we derived ras under the influence of forest vegetation for five cases that depend on the canopy height and structure. Three parameterization schemes for ras were then integrated into a distributed hydrologic model: (1) the aerodynamic resistance above the canopy, ignoring the canopy structure effects on ras, (2) the full aerodynamic resistance formulation for the different canopy height cases, and (3) a simplified formulation that only represented the lower trunk layer. Model simulations were conducted at six snow telemetry (SNOTEL) sites in the Verde River Watershed, Arizona, and evaluated with respect to snow water equivalent (SWE) product from the SNOTEL sites and a gridded product. Results revealed the importance of accurately parameterizing vegetation canopy structure when calculating ras in forested regions. Cases where ras included the vertical structure effects showed improved simulations of SWE across all sites. Finally, ras is mostly determined by trunk layer aerodynamic resistance such that the simplified formulation is sufficient for representing forest canopy effects on ras. [ABSTRACT FROM AUTHOR]

Efficient energy storage is becoming a serious niche area nowadays due to exponential growth in energy consumption. Different approaches have been developed and implemented to improve the performance of the devices, in which improving conductivity is a major issue. In the present work, cotton fabric was converted into a conductive material by incorporating graphene, using the Layer-by-Layer (LBL) method, followed by heating at 100 °C. The electrical conductivity of the cotton using different concentrations of graphene was studied. The graphene-coated cotton, at the 17th layer, with a concentration of 168.36 wt.% resulted in a surface resistance of 0.644 Ω/sq and retained the maximum resistance even after two months. Scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy analysis (EDX) were employed to comprehend the surface morphology and elemental compositions. Fourier transform infrared (FTIR) spectroscopy, UV-vis absorption, and X-ray diffraction (XRD) were used to determine the structural analysis, which revealed a good dispersion of graphene in the cotton samples obtained through dimethyl sulfoxide (DMSO) doping, which reduced the ripple of the cotton. The cotton fabric treated with graphene was thermally stable, as shown through thermal analysis. From the results obtained, it is evident that graphene-treated cotton fabric materials show tremendous potential for use in smart textiles and also as protective clothing. [ABSTRACT FROM AUTHOR]

Niobium superconducting radiofrequency cavities enable applications in modern accelerators and quantum computers. However, the surface resistance significantly deteriorates the cavities’ performance. Nitrogen doping surface treatment can consistently increase cavity performance by reducing surface resistance, but the improvement mechanism is not fully understood. Herein, we employed transmission electron microscopy and spectroscopy to uncover the structural and chemical differences of the Nb/air interface between the non-doped and nitrogen-doped cavities. The results indicate that nitrogen doping passivates the Nb surface by introducing a compressive stress/strain close to the Nb/air interface, which impedes the diffusion of oxygen and hydrogen atoms and reduces surface oxide thickness.

The accuracy of the RCS (Radar Cross Section) test is closely related to the conductivity of the model surface. The Chinese military standard has stringent surface resistance criteria for models. If the resistance criteria are appropriately relaxed, model processing can be more effective and expenses can be reduced. However, there are few quantitative evaluations of the relationship between surface resistance and RCS test error, making it impossible to design the model surface resistance in accordance with RCS test accuracy requirements. In this paper, firstly, the influence of model surface resistance on RCS is clarified through theoretical, simulation, and experimental research. The RCS analysis approach of the finite conductivity model is established. Subsequently, taking various typical shapes as research objects, such as the sphere, cube, flying wing aircraft, wing-body combination, and stealth aircraft, the simulation analysis of radar scattering characteristics is carried out under varied sheet resistances and multiple frequencies. A more attainable surface conductivity control standard for the RCS test model has been formulated, which is relaxed by 93% and 727% for models with average RCS of less than and higher than −30dBsm compared with the indicator in the Chinese military standard.