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Image regularised features play a critical role in image processing domain, by integrating regularised feature and structural similarity, a new full-reference image assessment method (IRF_SSIM) is proposed in this study. As well known, the gradient operator always be used to capture the edge information of the image, while the total variational regularised features can be adopted to calculate the detailed change information of image contrast and texture, as well as noise removal and edge retention. Therefore, the IRF_SSIM method extends the gradient features into the image regularised features to measure the structural changes in the image. In addition, image quality is also affected by variations of luminance and contrast. For a more comprehensive image quality assessment, the IRF_SSIM method considers the changes in structure, luminance and contrast simultaneously. In other words, the total image quality is estimated by structural similarity calculated by integrating the effects of image structure, luminance and contrast changes. Comparing with the representative methods, the experimental results illustrate that the IRF_SSIM method is highly consistent with the subjective assessment results.

In this paper, we investigate the physical layer security (PLS) in wireless ad hoc networks (WANETs). For fixed transmission distance model, we introduce the jammer selection scheme to enhance the secrecy transmission capacity. The jammer can prevent the eavesdropper from stealing information by sending the interference signal to the eavesdropper, thereby improving the security of the system. Based on the probability density function (PDF) and cumulative distribution function (CDF) of a random variable, we establish the expression of secrecy outage probability (SOP), a main metric in PLS. Finally, simulated results validate the effectiveness of selecting the appropriate jammer and theoretical analysis.

Micromotion characteristics of conical-shaped high-speed moving targets are presented using the Lorentz finite-difference time-domain (Lorentz-FDTD) method. This research discusses the transformation formulas of the space and time increments, the incident wave, the field components between the moving system, and the laboratory system in case of a micromotion target. The validity and accuracy of the proposed transformation formulas are verified by presenting the results for a moving cone and a hemisphere–cylinder combination target.

Nanocomposites of CoNi alloy nanoparticles loaded on Ketjenblack carbon (CoNi/KB) are successfully prepared through one-pot thermal decomposition of organic precursor solution. It can be proved, through a serious of characterization methods, that the introduction of porous carbon nanospheres with high specific surface area effectively prevents the serious agglomeration and oxidation of alloy nanoparticles. Highly dispersed CoNi alloy nanoparticles are evenly distributed on the surface of carbon nanospheres with a size of about ca. 5 nm. The CoNi/carbon nanosphere composites exhibit excellent electromagnetic wave absorbability when the doping mass is merely 15 wt% with the minimum reflection loss of −39.5 dB at 12.4 GHz and the effective absorption bandwidth (

In this study, a series of cyclic tests on a 304L stainless steel with different loading paths were conducted. It revealed that as the non-proportionality of loading path increased, the growth rate of martensitic content became higher and its distribution among the austenitic matrix appeared more uniform. A phase transformation kinetics equation was modified to describe the effect of cumulative plastic strain, loading amplitude and loading path on martensitic transformation. A stress decomposition rule was proposed to incorporate both the non-proportional hardening and martensitic transformation hardening to describe the hardening mechanism.

The visible-light responsive BiVO4/TiO2 core–shell heterojunction photocatalyst was prepared by precipitation method. The crystal structure and optical properties of the samples were characterized. The XRD results indicated that the vector was anatase TiO2. EDS, XPS and XRD showed that BiVO4 was coated on the surface of TiO2. SPV and UV–Vis spectra certified that the BiVO4/TiO2 photocatalyst possessed better absorption in the visible-light region (425–470 nm). The optical band gap of BiVO4/TiO2 photocatalyst ranged from 2.38 to 2.14 eV and decreased with the BiVO4 amount increase from 2 to 6 mmol L−1. Compared to TiO2, the BiVO4/TiO2 photocatalyst exhibited much higher photocatalytic activity in degradation of methyl orange under visible light irradiation and lower photocatalytic activity in UV-light. Moreover, the effect of the different in formation mechanism of TiO2/BiVO4 and BiVO4/TiO2 on the photocatalytic activity was investigated in detail. The photocatalytic mechanism of BiVO4/TiO2 core–shell structure was discussed, which indicated that photoelectron reduction was the major degradation mechanism in this system. When TiO2 particles were properly coated with BiVO4 layer and the Bi/Ti molar ratio of 1:32, the composite photocatalyst could absorb UV-light and visible light at the same time, so the BiVO4/TiO2 core–shell heterojunction photocatalyst had the optimal photocatalytic activity in visible light irradiation, which was attributed to the spatial transfer of visible-excited high-energy electrons from TiO2 to BiVO4.

Uniaxial tensile tests and low cycle fatigue tests were performed on 304 stainless steel treated with different torsional pre-strains. The relationship between torsional pre-strain and mechanical properties is established. Furthermore, the changes in the amount of martensite phase transitions are measured during low cycle fatigue tests and after specimen fracture are observed. This is mainly because martensitic transformation is a frequent phenomenon during plastic deformation, which is closely related to the mechanical properties. In this study, it is found that torsional pre-strain increases yield strength and reduces elongation. The ductility of 304 stainless steel decreases with the increase of torsional pre-strain, while its fatigue life does not. As the amplitude of torsional pre-strain increases, the fatigue life of the material changes in s-type. In particular, the fatigue life increases when the torsional pre-strain is between 5% and 8%. From the analysis of the microcosmic distribution of the martensite, it is found that the fatigue life is affected by the combined action of martensite transformation and ductility. The test results suggest that it should skip the relatively dangerous small strain area when improving mechanical properties of 304 stainless steel by way of changing shear pre-strain.

The rapid development of urbanization and industrialization in recent decades has put huge pressure on water and energy supply. In this paper, the critical driving forces of water and energy consumption in China are investigated to reveal the linkage between water use and energy consumption changes. A modified Logarithmic Mean Divisia Index(LMDI) method is used to decompose the total effect of water and energy consumption to different driving factors with no residues generation. The total effect of water consumption change is decomposed into four driving factors including industrial water consumption, industrial structure, economic scale and population scale. Similarly, the total effect of energy consumption change is decomposed into three driving factors embracing consumption intensity, economic activity, and population. Then, we calculate contribution values of different driving forces and identify the major influencing factors. The results show that the growth of population and GDP per capita were dominant factors driving water and energy consumption, while the improvement of consumption intensity was inhibiting factor on consumption growth. The results may provide insights for synergetic management to alleviate the pressure caused by excessive water and energy consumption.

To improve the performance of bamboo and increase its utilization value, this study aimed at investigating the effects of impregnation pretreatment and thermal treatment on the structural changes of bamboo. The samples were pretreated in sodium hydroxide or zinc chloride solution, and then treated at 160 °C. The pretreated and control samples were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG), and Fourier transform infrared spectroscopy (FTIR). The results showed that the cellulose crystallinity and intensity of samples pretreated by ZnCl2 could be reduced, but the crystal structure remained the same. As for samples pretreated in NaOH, the crystal structure of fiber was destroyed and the crystallinity was increased significantly. High temperature treatment has little effect on the thermal stability of bamboo. However, after treatment with NaOH and ZnCl2, the thermal degradation temperature changed obviously and moved to a lower temperature. ZnCl2 pretreatment had influence on the chemical structure of bamboo, while NaOH pretreatment had greater influence on the chemical structure of bamboo.

To implement the Lorentz finite-difference time-domain (FDTD) method in a 3D case, this communication presents the transformation formulas of the spatial and time increments, the field components, and the incident plane wave between the moving system and the laboratory system. The radiated fields from a moving dipole source are shown to verify the accuracy and validity of the proposed transformation formulas. The relative errors are within an acceptable range. The scattered fields of a moving metallic sphere are also illustrated to verify the validity of the proposed method. And, the scattered fields from a complex pyramid-shaped target are discussed.

A novel laboratory-scale aerobic submerged membrane bioreactor integrating sponge-plastic biocarriers (SPSMBR) was conducted to study the removal and degradation mechanisms of sulfonamide antibiotics (SAs). Experimental results indicated that SPSMBR had a better removal of sulfadiazine (91% SDZ) and sulfamethoxazole (88% SMZ) than that of a conventional aerobic submerged membrane bioreactor (CSMBR) (76% SDZ and 71% SMZ, respectively). Material balance calculations suggested that biodegradation is the primary removal mechanism of SDZ and SMZ. Protein (tyrosine-like materials) significantly affected the removal of SAs. Moreover, the SPSMBR exhibited its better performance in removing SAs due to more abundance of tyrosine-like materials. The 16S rRNA sequencing showed that biocarriers could promote the enrichment of slow growing bacteria, especially Thermomonas, associated with the removal of SAs. Valuable insights into the removal and degradation mechanisms of SAs in the SPSMBR systems are documented here.

A series of solid and macroporous N-doped carbon nanofibers composed of Fe3C nanoparticles (named as solid Fe3C/N-C NFs, solid Fe3C/N-C NFs-1, solid Fe3C/N-C NFs-2, macroporous Fe3C/N-C NFs, macroporous Fe3C/N-C NFs-1 and macroporous Fe3C/N-C NFs-2, respectively) were prepared through carbonization of as-electrospun nanofiber precursors. The results show that the magnetic Fe3C nanoparticles (NPs) dispersed homogeneously on the N-doped carbon fibers; as-prepared six materials exhibit excellent microwave absorption with a lower filler content in comparison with other magnetic carbon hybrid nanocomposites in related literatures. Particularly, the solid Fe3C/N-C NFs have an optimal reflection loss value (RL) of −33.4 dB at 7.6 GHz. For solid Fe3C/N-C NFs-2, the effective absorption bandwidth (EAB) at RL value below −10 dB can be up to 6.2 GHz at 2 mm. The macroporous Fe3C/N-C NFs have a broadband absorption area of 4.8 GHz at 3 mm. The EAB can be obtained in the 3.6–18.0 GHz frequency for the thickness of absorber layer between 2 and 6 mm. These Fe3C–based nanocomposites can be promising as lightweight, effective and low-metal content microwave absorption materials in 1–18 GHz.

Electrospinning and annealing methods are applied to prepare cobalt nanoparticles decorated in N-doped carbon nanofibers (Co/N-C NFs) with solid and macroporous structures. In detail, the nanocomposites are synthesized by carbonization of as-electrospun polyacrylonitrile/cobalt acetylacetonate nanofibers in an argon atmosphere. The solid Co/N-C NFs have lengths up to dozens of microns with an average diameter of ca. 500 nm and possess abundant cobalt nanoparticles on both the surface and within the fibers, and the cobalt nanoparticle size is about 20 nm. The macroporous Co/N-C NFs possess a hierarchical pore structure, and there are macropores (500 nm) and mesopores (2-50 nm) existing in this material. The saturation magnetization ( Ms) and coercivity ( Hc) of the solid Co/N-C NFs are 28.4 emu g-1 and 661 Oe, respectively, and those of the macroporous Co/N-C NFs are 23.3 emu g-1 and 580 Oe, respectively. The solid Co/N-C NFs exhibit excellent electromagnetic wave absorbability, and a minimum reflection loss (RL) value of -25.7 dB is achieved with a matching thickness of 2 mm for solid Co/N-C NFs when the filler loading is 5 wt %, and the effective bandwidth (RL ≤ -10 dB) is 4.3 GHz. Moreover, the effective microwave absorption can be achieved in the whole range of 1-18 GHz by adjusting the thickness of the sample layer and content of the dopant sample.

Noninvasive methods for precise characterization of the thermal properties of soft biological tissues such as the skin can yield vital details about physiological health status including at critical intervals during recovery following skin injury. Here, we introduce quantitative measurement and characterization methods that allow rapid, accurate determination of the thermal conductivity of soft materials using thin, skin-like resistive sensor platforms. Systematic evaluations of skin at eight different locations and of six different synthetic skin-mimicking materials across sensor sizes, measurement times, and surface geometries (planar, highly curvilinear) validate simple scaling laws for data interpretation and parameter extraction. As an example of the possibilities, changes in the thermal properties of skin (volar forearm) can be monitored during recovery from exposure to ultraviolet radiation (sunburn) and to stressors associated with localized heating and cooling. More generally, the results described here facilitate rapid, non-invasive thermal measurements on broad classes of biological and non-biological soft materials., GRAPHICAL ABSTRACT

This study investigated the effect of N-acyl-L-homoserine lactones (AHLs) and EPS on anammox activity, and identified the relationship between AHLs and EPS. The effects of AHLs and different EPS fractions (loosely bound (LB) and tightly bound (TB) EPS) from denitrification sludge (DS) and perchlorate reducing sludge (PRS) on anammox activity were conducted by batch experiments. Compared with the control experiment, the nitrogen removal rate was increased by 82.0%, 73.9% and 73.0%, respectively, when adding DS-EPS (integral DS EPS), PRS-EPS (integral PRS EPS) and DS-LB in anammox biomass. EPS fractions of DS and PRS contained the same kinds of AHLs, including C4-HSL, C6-HSL and C8-HSL, as identified by HPLC-MS. C4-HSL and C6-HSL at 0.1 mg L−1 concentration effectively improved the nitrogen removal rate by induceing the expression of anammox active genes during the anammox process. This study provides a new idea for efficient nitrogen removal from anammox bacteria.

Wire arc additive manufacturing (WAAM) with many superior characteristics, such as high deposition rate, low cost, free shape, and environmental friendliness has attracted much attention and will be used in the nuclear industry. A 308 L stainless steel plate with 40 deposited layers was manufactured by WAAM and further treated into solution treatment status in this work. A ferrite formation model was proposed based on the detailed microstructural characterization at different layers where the consistently large columnar austenite grains and small ferrite grains with different shapes including skeletal, lathy and granular coexisted. Furthermore, monotonic tensile tests with the specimens extracted from the top, middle and bottom layers of the WAAM plate were carried out to evaluate the mechanical properties, and relatively consistent strength was revealed. Moreover, an interrupted test was performed to investigate the role of ferritic and austenitic phases on the deformation mechanisms of the WAAM material under monotonic tensile loading. It was shown that the deformation behavior was primarily controlled by the single slip and double slip of dislocations of austenitic matrix and ferrite, and the lathy ferritic grains and austenitic grains dominated the fracture behavior.

A water-soluble polysaccharide, named NCSP-50, was obtained from natural Cordyceps sinensis by hot water extraction and ethanol fractionation precipitation. It was eluted as a single symmetrical peak and had an average molecular weight of 9.76 × 10 5 Da. The structure was determined by monosaccharide composition, methylation analysis, 1D/2D NMR spectroscopy, and enzymatic hydrolysis and characterization of the oligosaccharides by MALDI-TOF mass spectrometry. The repeating unit of this polysaccharide was proposed as follows: Download high-res image (64KB) Download full-size image This glucan showed potent immunostimulatory activity on the basis of its significant abilities to promote macrophage proliferation, enhance NO production, as well as and cytokines (IL-1β and TNF-α) secretion.

Photo-responsive materials with tunable properties by multiple stimuli have been widely used as molecular machines, molecular logic gates, optical data storages, etc. In this work, we report a rhodamine B-based photo-responsive system, whose properties could be facilely modulated by metal ions (Zn(II), Ni(II) and Hg(II)). These metal ions endow the complexes (L-Zn, L-Ni and L-Hg) with similar photochromic property but distinctly different photo-induced fluorescence change. Upon UV light irradiation, the spirolactam ring in rhodamine B moiety turned from a close form to an open form, along with enlarged conjugated structure with intense absorbance. Interestingly, fluorescence “turn off”, “no change” and “turn on” responses were induced by Zn(II), Ni(II) and Hg(II) respectively upon UV light irradiation. Taking advantage of the prominently different characteristics caused by metal ions, different logic gates were designed by simply varying the inputs of metal ions and UV light. This work provided a new strategy for developing multifunctional photo-responsive materials, which were further beneficial for constructing photo-controlled logic gates with tunable performance.

In order to remove speckle noise of synthetic aperture radar (SAR) images, we proposed a high order variational model based on G0 distribution. Specifically, the model combines the total variation(TV) and total curvature(TC) regularizations. Besides, considering the terrain backscatter, we derived a new data fidelity term. Thus the new variational model can reduce the staircase effect, meanwhile effectively preserve the image features such as the edge, corner and fine details. Since the model has the characteristics of nonlinear, non-convex and non-smooth, we transformed it into an alternating optimization problem by importing auxiliary variables. Then, we designed a fast numerical approximation iterative scheme for proposed model. Qualitative and quantitative experiments on both synthetic and real SAR images were implemented to indicate the advantages of the proposed model and the high computation efficiency of the designed algorithm.

Cavitation intensity is affected by ultrasonic intensity (UI) and is a key parameter to describe experimental results during ultrasonic treatment. The relationship between the UI and physicochemical properties of Chinese fir was investigated. In this study, four frequencies (25, 28, 40, and 59 kHz) were used at the same intensity of 240 W and the same duration of 35 min. The UI during the ultrasonic treatment was determined, and the chemical components were determined. The chemical structure, crystallinity, morphology, and extractives of wood were respectively analyzed by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and gas chromatography-mass spectrometry (GC–MS). The results showed that higher crystallinity was associated with a larger integrated area under the curve of the ultrasonic intensity (UIA). The largest UIA was observed at 25 kHz, followed by those at 40, 59, and 28 kHz. The relative content of hemicellulose was strongly affected by the ultrasonic treatment. No chemical reactions were observed in the wood, whereas the ultrasonic treatment affected the torus of the bordered pits and facilitated the migration of extractives. In general, the higher the UIA, the stronger the effect of the cavitation was. The most significant changes in the physicochemical properties were observed at 25 kHz. The instantaneous ultrasonic intensity (IUI) changed over time, and the UIA was closely associated with changes in the physicochemical properties of the wood. The results of this study demonstrate that UI has a significant influence on the physicochemical properties of wood.

As the growing demand for environmental CO 2 emission reduction, low-carbon electricity has draw more attention. Integrated energy system (IES) is an important carrier for energy conservation and emission reduction. In the traditional low-carbon dispatch model for IES, carbon emission calculation is independent of the IES internal structure. Aiming for further control of carbon emissions according to carbon distribution in the energy conversion process, this paper establishes a modified low-carbon economic dispatch model for IES, which is based on carbon emission flow (CEF) for an energy hub and carbon trading. Before practical dispatch, analyze the carbon emission flow between different energy converters and bunches in the IES. Then carbon trading cost is considered in the optimal economic dispatch. The case study of models which applied to IES with combined cooling, heating and power units (CCHP), indicates that the proposed model controls carbon emission more stringent and is sensitive to carbon trading price.

Energy shortage and water stress are two major environmental pressures during the rapid economic development and urbanization processes. In China, Coal-based energy excavation and treatment processes consume large amounts of water resource. Obtaining a clear understanding of water consumption in the energy production process plays a critical role in addressing the problems of energy shortage and water scarcity. The Logarithmic Mean Divisia Index(LMDI) method can reveal the driving forces behind water consumption changes in energy production. The results show that the growth of population and GDP per capita were dominant factors driving water consumption changes, while the improvement of consumption intensity and structure were main inhibiting factor on water consumption growth. The results may provide insights for synergetic management to alleviate the pressure caused by excessive water and energy consumption.

Sharp increases in energy consumption have led to increases in fine particulate matter emissions in the Jing-Jin-Ji region. In this study, PM2.5 emissions of various sectors were assessed from the production-, consumption-, and income-based perspectives by multiple principles accounting analysis. The key drivers of PM2.5 emission changes were identified by structural decomposition analysis, then the flow patterns were determined by input–output analysis. Consumption-based and income-based accounting methods were used to investigate PM2.5 emissions for 21 sectors using the production-based emission inventory in the Greenhouse Gas Air Pollution Interaction and Synergies model for the Jing-Jin-Ji region and an environmentally extended input–output framework. Structural decomposition analysis was then used to identify the socioeconomic drivers of changes in PM2.5 emissions in the Jing-Jin-Ji region between 2002 and 2015 from consumption- and income-based perspectives. Inter-provincial flow patterns for consumption-driven and supply-driven PM2.5 emissions were then identified by performing input–output analysis. The results indicated that transport and storage, electricity, hot water, gas, and water production and supply and services are the key sectors emitting PM2.5 from the production-, consumption-, and income-based perspectives, respectively. The emission intensity is a crucial socioeconomic driver affecting changes in PM2.5 emissions. The inter-provincial PM2.5 flow results indicated that Beijing is a consumption- and supply-driven net importer of PM2.5 emissions and Hebei is a net exporter. The results will help in the development of measures to mitigate demand-side and supply-side PM2.5 emissions and of coordinated multi-regional policies for the Jing-Jin-Ji region.

Plasmonic nanostructures are often used in surface-enhanced infrared absorption (SEIRA) spectroscopy to probe surface assembled molecules or the dielectric environment surrounding the metallic nanostructures. Here we fabricate metallic nanogap structures using self-aligned techniques on an intrinsic silicon substrate and correlate resulting SEIRA spectra with the choice of metal nanostructure geometry. A motivation is to compare the enhancement from hybridization of bright plasmon modes with the effect of hybridization between bright and dark plasmon modes. These structures provide a gap size below 10 nm and support strong field enhancements. The structures demonstrate their sensitivity through the enhanced absorption signature of the Si–O stretch in the native silicon oxide layer of nanometer thickness beneath the metal. Simulations reveal this thin layer plays a critical role in determining the plasmon modes of the nanostructures. Numerical simulations of the optical properties are consistent with the o...

The relationship between the urban population and urban construction land is an important indicator for assessing urbanization quality. With the rapid growth of urban population and the drastic expansion of urban construction land, human-land contradictions have become a major factor restricting the sustainable development of cities. This paper analyzes the coordination relationship between the urban population and urban construction land at the national, provincial and provincial-capital scales in China in recent years. The results show that the expansion rate of urban construction land in China is generally faster than the growth rate of the urban population, resulting in an overall discordant human-land relationship. Although the regional differences in the uncoordinated allocation of urban population and urban expansion gradually narrowed from 2010–2017, there was still mismatch among provinces. The relationship between the urban population and urban construction land trends was mainly coordinated at the provincial scale and uncoordinated at the provincial capital scale. By combining the coordination degrees at the provincial and provincial-capital scales, we identify six combined development types and analyze the combined characteristics of urban population growth and urban construction land expansion. It is necessary to formulate differentiated policies to guide urban population development and urban construction land use at different scales. These findings provide a theoretical basis for alleviating the human-land contradiction and achieving sustainable urban development.

CoFe2O4 nanocrystals decorated in mesoporous carbon nanofibers (CoFe2O4/C NFs) are prepared by electrospinning and subsequent calcination. The CoFe2O4/C NFs exhibit optimal electromagnetic waves absorption performance. The minimum reflection loss (RL) of CoFe2O4/C NFs reaches −14.0 dB at a frequency of 9.0 GHz and a thickness of 3.5 mm with low doping mass of 20 wt%. In addition, the maximum effective absorption bandwidth range (RL ≤ -10 dB) is 3.6 GHz with a thickness of 2.5 mm. The interfacial polarization effect of the material itself and the synergistic effect between the binary components are promoted by combining one dimensional (1D) carbon nanofibers with magnetic CoFe2O4 spinel nanocrystals. Therefore, this strategy can achieve good impedance matching and effectively improve the absorbing properties of our materials. This work shows that enriching the diversity of material loss mechanisms, constructing hierarchical nanostructures of fibers, the simple and mature preparation methods can make CoFe2O4/C NFs composites a potentially new-type of microwave absorbing material which can be easily put into production.

Cadmium (Cd) is a widespread environment contaminant due to the development of electroplating and metallurgical industry. Cd can be enriched by organisms via food chain, causing the enlarged environmental problems and posing threats to the health of humans. Polydatin (PD), a natural stilbenoid compound derived from Polygonum cuspidatum, shows pronouncedly curative effect on oxidative damage. In this work, the protective effects of PD on oxidative damage induced by Cd in Musca domestica (housefly) larvae were evaluated. The larvae were exposed to Cd and/or PD, subsequently, the oxidative stress status, mitochondria activity, oxidative phosphorylation efficiency, and survival rate were assessed. Cd exposure generated significant increases of malondialdehyde (MDA), reactive oxygen species (ROS) and 8-hydroxy-2-deoxyguanosine (8-oxoG) in the housefly larvae, causing mitochondrial dysfunction and survival rate decline. Interestingly, pretreatment with PD exhibited obviously mitochondrial protective effects in the Cd-exposed larvae, as evidenced by reduced MDA, ROS and 8-oxoG levels, and increased activities of superoxide dismutase (SOD), mitochondrial electron transfer chain, and mitochondrial membrane potential, as well as respiratory control ratio. These results suggested that PD could attenuate Cd-induced damage via maintaining redox balance, stimulating SOD activity, and regulating mitochondria activity in housefly larvae. As a natural polyphenolic chemical, PD can act as a potential candidate compounds to relieve Cd injury.

A common problem existing in wound dressing is to integrate the properties of against water erosion while maintaining a high water-uptake capacity. To tackle this issue, we imbedded one layer of hydrogel nanofibrous mat into two hydrophobic nanofibrous mats, thereafter, the sandwich structural membrane (SSM) was obtained. Particularly, SSM is composed of three individual nanofibrous layers which were fabricated through sequential electrospinning technology, including two polyurethane/antibacterial agent layers, and one middle gelatin/rutin layer. The obtained SSM is characterized in terms of morphology, component, mechanical, and functional performance. In addition to the satisfactory antibacterial activity against Staphylococcus aureus and Escherichia coli, and antioxidant property upon scavenging DPPH free radicals, the obtained SSM also shows a desirable thermally regulated water vapor transmission rate. More importantly, such SSM can be mechanically stable and keep its intact morphology without appearance damage while showing a high water-absorption ratio. Therefore, the prepared sandwich structural membrane with hydrogel nanofibrous mat as inner layer can be expected as a novel wound dressing.

The scattered properties in the far-field region of an ellipsoid target., moving at high speed., are presented by a three-dimensional Lorentz Finite-Difference Time-Domain (FDTD) method. When the target is rest., the results are in good agreement with those by the MoM method and the conventional FDTD method. Numerical results show that the radar cross section (RCS) in the far-field region from the moving target is modulated by the moving speed.

This paper investigated a strategy to minimize membrane fouling and increase treatment efficiency through an investigation of a specific approach by adding sponges into a conventional submerged anaerobic membrane bioreactor (CAnSMBR). During the operation, the protein-based soluble microbial products as the main factor affecting the membrane fouling could be reduced by sponge addition in the CAnSMBR (SAnSMBR). Furthermore, reducing HRT from 18 h to 12 h could shorten the membrane fouling cycle to 62% and 87% in CAnSMBR and SAnSMBR, respectively. At the initial of COD/NO3 ratio ranges from 5 to 4, only 88% of nitrogen in CAnSMBR was removed, while the SAnSMBR could remove more than 90%. TOC removal efficiency could reach more than 95% under a good stirring scenario. It is evident that the SAnSMBR is a promising solution for improving overall CAnSMBR performance and substantially mitigating membrane fouling.

The scattered properties of a cone-sphere target, moving at high speed, are presented by a three-dimensional Lorentz-FDTD method. Numerical results show that the amplitudes of the scattered wave are modulated by the movement of target. Moreover, different operating frequencies cause different amplitudes of scattered wave for the same moving speed of target.

A lossy Drude dispersive medium is used to analyze the propagation properties of the low-frequency electromagnetic wave under the rough sea surface. Numerical results in f=150Hz are illustrated for two different rough sea surfaces. It is noted that the rough sea surface affects the phase and amplitude distributions of the low-frequency electromagnetic wave.

Substrate termination of lateral 600 V-class GaN-on-Si HEMTs and half-bridges other than source-connection is investigated: Using conductive Si-substrates as current-return path and the GaN-buffer for high-side transistor-to-heatsink isolation eliminates parasitic inductances and thermal interfaces. Floating-substrate reduced 440 V switching times to 60% (reduced output capacitance) and fixed-to-ground substrate thermal resistance to 54%. However, substrate-to-gate capacitive-coupling significantly increases gate-charge which is analyzed using four-terminal measurements and simulations. Measured high-side current-collapse with fixed-to-ground high-side substrate termination (switching over 300 V, 2 MHz) is more pronounced in first-quadrant compared to third-quadrant conduction, and explained by dynamic source-access-region voltage feedback to the source-referenced gate-driver.

Photo-responsive materials with good luminescence performance in solid state have received widespread attention. However, the reported luminescent photo-responsive systems exhibit either only color change or both color and luminescence changes in solid state upon UV light irradiation. Developing photo-responsive materials with only tunable luminescence signals in solid state remains a great challenge for constructing concealed anti-counterfeit materials. In this work, a novel luminescent photo-responsive molecule (TPE-TS) was developed, which exhibited intense fluorescence emission due to the aggregation-induced emission (AIE) characteristic from its tetraphenylethene moiety. After irradiated by UV light, an isomerization from thio-keto form to thio-enol form took place in the thiosemicarbazide group, accompanied with obvious fluorescence quenching. Interestingly, there was no visible color variation before and after UV light irradiation owing to the small conjugated structure of TPE-TS. Taking this unique photo-responsive property, a concealed anti-counterfeit paper was successfully prepared. Letters could be recorded by UV light on this paper, hided under daylight and only visible again by UV light, demonstrating an excellent concealed performance as an anti-counterfeit material.

The effects of loading path and strain amplitude ratio on the cyclic behavior and fatigue life were investigated on a 316LN nuclear grade stainless steel employing a series of symmetrically strain-controlled fatigue tests at room temperature. The loading paths of Uniaxial, Torsional, Proportional, Rhombic, Rectangular, and Circular were employed with the constant equivalent strain amplitude of 0.5%. The strain amplitude ratio of 2.35, 1.73 and 1.27, defined by the ratio of shear strain amplitude to the axial strain amplitude, was realized by changing the shear strain amplitude under Proportional, Rhombic, Rectangular and Elliptical loading paths. As expected, the significant non-proportional additional hardening was observed. It’s interesting to note that the axial cyclic stress response varied with the strain amplitude ratio, and the law was different under different loading paths. The fatigue life of all the tests were evaluated by three critical plane criteria proposed by Smith-Watson-Topper (SWT), Fatemi-Socie (FS) and Chen-Xu-Huang (CXH). Results show that the SWT criterion significantly overestimated the fatigue life of non-proportional loading because the effect of shear damage was not considered. The CXH criterion for tensile-type failure yielded good prediction results except for two torsional data points. The FS criterion provided better predictions than other models.

We observe large, reversible, bias driven changes in the vibrational energies of PCBM, based on simultaneous transport and surface-enhanced Raman spectroscopy (SERS) measurements on PCBM-gold junctions. A combination of linear and quadratic shifts in vibrational energies with voltage is analyzed and compared with similar measurements involving C60-gold junctions. A theoretical model based on density functional theory (DFT) calculations suggests that both a vibrational Stark effect and bias-induced charging of the junction contribute to the shifts in vibrational energies. In the PCBM case, a linear vibrational Stark effect is observed due to the permanent electric dipole moment of PCBM. The vibrational Stark shifts shown here for PCBM junctions are comparable to or larger than the charging effects that dominate in C60 junctions., 16 pages, 4 figures

The urban population (UP) measure is one of the most direct indicators that reflect the urbanization process and the impacts of human activities. The dynamics of UP is of great importance to studying urban economic, social development, and resource utilization. Currently, China lacks long time series UP data with consistent standards and comparability over time. The nighttime light images from the Defense Meteorological Satellite Program’s (DMSP) Operational Linescan System (OLS) allow the acquisition of continuous and highly comparable long time series UP information. However, existing studies mainly focus on simulating the total population or population density level based on the nighttime light data. Few studies have focused on simulating the UP in China. Based on three regression models (i.e., linear, power function, and exponential), the present study discusses the relationship between DMSP/OLS nighttime light data and the UP and establishes optimal regression models for simulating the UPs of 339 major cities in China from 1990 to 2010. In addition, the present study evaluated the accuracy of UP and non-agricultural population (NAP) simulations conducted using the same method. The simulation results show that, at the national level, the power function model is the optimal regression model between DMSP/OLS nighttime light data and UP data for 1990–2010. At the provincial scale, the optimal regression model varies among different provinces. The linear regression model is the optimal regression model for more than 60% of the provinces. In addition, the comparison results show that at the national, provincial, and city levels, the fitting results of the UP based on DMSP/OLS nighttime light data are better than those of the NAP. Therefore, DMSP/OLS nighttime light data can be used to effectively retrieve the UP of a large-scale region. In the context of frequent population flows between urban and rural areas in China and difficulty in obtaining accurate UP data, this study provides a timely and effective method for solving this problem.