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Recent study has found excellent bulk and surface insulation property of Si 3 N 4 ceramic which make it potential to serve as key insulation component in various energy transmission apparatus. Charge accumulation at gas-solid interface is a critical insulation property but few relevant study on Si 3 N 4 can be found. This contribution has investigated the surface charge property of Si 3 N 4 ceramic compared to traditional insulation polymer under different electrical-thermal stress. Through its comparison with the electric field distribution, the main source of the surface charge accumulation is analyzed, indicating that the superior surface charge suppression performance of Si 3 N 4 lies on its low carrier density and conduction barrier, which considerably prevent charge injection and suppress the normal electric field which drives the charge to the gas-solid interface. The proposed mechanism is also validated by the characterization on conducting and space charge property for Si 3 N 4 as well as dynamic simulation on surface charge accumulation. [ABSTRACT FROM AUTHOR]

The treatment of oil and water pollutants generated in industrial production and daily life is an urgent issue that needs to be addressed globally. Inspired by superhydrophobic self-cleaning lotus leaves, durable and sturdy superhydrophobic water-filled barriers, and lightweight bird bones with hollow structures, researchers can obtain superhydrophobic surfaces by creating rough surfaces of layered micro- and nanostructures. In this study, hydrophobic polycaprolactone (PCL) membranes with layered structures were prepared by electrospinning. The surface roughness of the PCL membrane was improved by compounding graphene oxide (GO) functional components on the PCL membrane surface, thereby enhancing its hydrophobicity. The infrared spectrum of the PCL/GO membrane shows that PCL and GO are physically mixed, and no chemical changes occur during the electrospinning process. Scanning electron microscopy (SEM) images of the composite fibre membranes reveal the interconnections between fibres. Fourier transform infrared spectroscopy (FTIR) provides information on the chemical components of the membranes. Thermogravimetric analysis (TGA) was employed to assess the thermal stability of the membranes. The oil-water separation test demonstrated that the PCL/GO membrane exhibited a separation efficiency of 99.94% for hexane-water mixtures. In the oil adsorption test, the maximum adsorption capacity of the membrane for n-hexane was 35.8 g/g. In the contact angle measurement experiment, the water contact angle of the nanofiber membrane increased from 120.12° to 140.15° with increasing GO content, indicating that the composite membrane exhibited enhanced hydrophobicity. [Display omitted] • Hydrophobic polycaprolactone (PCL) membranes with layered structures prepared by electrospinning technology. • Surface roughness of PCL membrane improved by graphene oxide (GO) functional components. • The separation efficiency of PCL/GO membrane for hexane-water mixture is as high as 99.94%. • The increase of GO content improved hydrophobicity of composite membrane. [ABSTRACT FROM AUTHOR]

In the development and production process of domestic and foreign oil fields, large amounts of oil-bearing wastewater with complex compositions containing toxic and harmful pollutants are generated. These oil-bearing wastewaters will cause serious environmental pollution if they are not effectively treated before discharge. Among these wastewaters, the oily sewage produced in the process of oilfield exploitation has the largest content of oil-water emulsion. In order to solve the problem of oil-water separation of oily sewage, the paper summarizes the research of many scholars in many aspects, such as the use of physical and chemical methods such as air flotation and flocculation, or the use of mechanical methods such as centrifuges and oil booms for sewage treatment. Comprehensive analysis shows that among these oil-water separation methods, membrane separation technology has higher separation efficiency in the separation of general oil-water emulsions than other methods and also exhibits a better separation effect for stable emulsions, which has a broader application prospect for future developments. To present the characteristics of different types of membranes more intuitively, this paper describes the applicable conditions and characteristics of various types of membranes in detail, summarizes the shortcomings of existing membrane separation technologies, and offers prospects for future research directions. [Display omitted] • Summarize the research of use of physical and chemical methods, or mechanical methods for sewage treatment. • Describes the applicable conditions and characteristics of various types of membranes. • Provide new insight on material design for membrane separation technologies. [ABSTRACT FROM AUTHOR]

The objective of the current study was to investigate the effect of dietary β-alanine supplementation on growth performance, meat quality, antioxidant ability, carnosine content, and gene expression of carnosine-related enzymes in broiler chicks. We randomly assigned 540 1-day-old Arbor Acres broilers to 5 dietary treatments supplemented with 0 (control group), 250, 500, 1,000, or 2,000 mg/kg of β-alanine (mg β-alanine per kg feed). Each treatment included 6 replicates of 18 birds. The feeding trial lasted for 42 d. Dietary β-alanine supplementation linearly and quadratically increased the average daily gain (ADG) during the starting period (d 1 to 21, P = 0.02 and P = 0.002). The feed conversion ratio (FCR) decreased quadratically in response to dietary β-alanine supplementation during the starting and entire periods (P < 0.001 and P = 0.003, respectively). For the entire period, the predicted best FCR would be achieved when β-alanine was fed at a level of 1,100 mg/kg from quadratic regression. The concentrations of carnosine and β-alanine in breast muscle increased quadratically with dietary β-alanine supplementation (d 42, P < 0.001 and P = 0.001, respectively). The predicted dietary β-alanine level for highest breast carnosine content was 1,196 mg/kg. Dietary supplementation with β-alanine reduced the taurine concentrations in plasma (d 42, linear and quadratic, P < 0.001). Breast muscle yield increased linearly and quadratically in response to dietary β-alanine addition (d 21, P = 0.017 and P = 0.007). Dietary supplementation with β-alanine quadratically reduced the shear force (P = 0.003), whereas a*45 min and a*24 h values increased quadratically in response to dietary β-alanine supplementation (d 42, P = 0.020 and P = 0.021, respectively). Dietary β-alanine addition quadratically enhanced the expression of carnosine synthase and taurine transporter mRNAs (P < 0.05). Overall, dietary β-alanine supplementation improved growth performance and carnosine content, ameliorated antioxidant capacity and meat quality, and upregulated the gene expression of carnosine synthesis-related enzymes in broiler chicks. [ABSTRACT FROM AUTHOR]

Carbonate weathering and the CO 2 consumption in karstic area are extensive affected by anthropogenic activities, especially sulfuric and nitric acids usage in the upper-middle reaches of Wujiang River, China. The carbonic acid would be substituted by protons from sulfuric and nitric acids which can be reduce CO 2 absorption. Therefore, The goal of this study was to highlight the impacts of sulfuric and nitric acids on carbonate dissolution and the associated deficit of CO 2 uptaking during carbonate weathering. The hydrochemistries and carbon isotopic signatures of dissolved inorganic carbon from groundwater were measured during the rainy season (July; 41 samples) and post-rainy season (October; 26 samples). Our results show that Ca 2 + and Mg 2 + were the dominant cations (55.87–98.52%), and HCO 3 – was the dominant anion (63.63–92.87%). The combined concentrations of Ca 2 + and Mg 2 + commonly exceeded the equivalent concentration of HCO 3 − , with calculated [Ca 2 + + Mg 2 + ]/[HCO 3 − ] equivalent ratios of 1.09–2.12. The mean measured groundwater δ 13 C DIC value (− 11.38‰) was higher than that expected for carbonate dissolution mediated solely by carbonic acid (− 11.5‰), and the strong positive correlation of these values with [SO 4 2 − + NO 3 − ]/HCO 3 – showed that additional SO 4 2 − and NO 3 − were required to compensate for this cation excess. Nitric and sulfuric acids are, therefore, suggested to have acted as the additional proton-promoted weathering agents of carbonate in the region, alongside carbonic acid. The mean contribution of atmospheric/pedospheric CO 2 to the total aquatic HCO 3 – decreased by 15.67% (rainy season) and 14.17% (post-rainy season) due to the contributions made by these acids. The annual mean deficit of soil CO 2 uptake by carbonate weathering across the study area was 14.92%, which suggests that previous workers may have overestimated the absorption of CO 2 by carbonate weathering in other karstic areas worldwide. [ABSTRACT FROM AUTHOR]

This paper presents two transitions between microstrip and stripline in Low Temperature Co-fired Ceramic technology, including a vertical transition and a coplanar transition for millimeter-wave application. These interconnects are simulated and optimized by a three-dimensional electromagnetic field simulator. Simulation results show that the return loss of microstrip to stripline vertical transition is less than −22 dB, and insertion losses are greater than 0.5 dB up to 35 GHz, and greater than 1 dB up to 40 GHz. Similarly, the return loss of the coplanar transition is less than −32 dB and insertion loss is better than 0.5 dB. LTCC test structures were fabricated and the performance of all transitions was successfully validated by scattering parameter measurements up to 40 GHz. [ABSTRACT FROM AUTHOR]

Abstract: The effect of Mn2+ ions on current efficiency (CE), deposit morphology and polarization behaviour during electrodeposition of zinc from acidic sulphate solutions was investigated. In the conditions studied, Mn2+ ions had no significant effect on CE over the concentration range of 1–10gdm−3. However, a decrease in CE of more than 35% was obtained at 50gdm−3. The cathodic polarization curves and the corresponding kinetics analysis demonstrated that this decrease in CE at higher concentrations of Mn2+ ions was due to the strong depolarizing effect of MnO4 − ions and other oxidized products of manganese. Moreover, the kinetics analysis of anodic polarization suggested that the presence of Mn2+ ions catalyzed the oxygen evolution reaction. The addition of Mn2+ ions was also observed to change the surface morphology and deposit quality of the electrodeposited zinc, affecting the crystallographic orientation by significantly inhibiting the growth of (002) and (100) planes. [Copyright &y& Elsevier]

Phenanthrene (Phe), a typical polycyclic aromatic hydrocarbon (PAH) pollutant, poses an enormous safety risk to rice-crab coculture (RC) paddy ecosystems. In this study, humic acid-modified purified attapulgite (HA-ATP) with a composite structure was successfully fabricated to adsorb PAHs released from paddy soil to overlying water in RC paddy ecosystems in Northeast China. The maximum crab bioturbation intensities for dissolved Phe and particulate Phe were 64.83nullng/L·(cm2·d) and 214.29nullng/L·(cm2·d), respectively. The highest concentration of dissolved Phe released from paddy soil to overlying water due to crab bioturbation reached 80.89nullng/L, while the corresponding concentration of particulate Phe reached 267.36nullng/L. The dissolved organic carbon (DOC) and total suspended solid (TSS) concentrations in overlying water increased correspondingly and were strongly correlated with dissolved Phe and particulate Phe concentrations, respectively (P < 0.05). When 6% HA-ATP was added to the surface layer of paddy soil, the efficiency of the adsorption of Phe release was 24.00%–36.38% for particulate Phe and 89.99%–91.91% for dissolved Phe. Because HA-ATP has a large adsorption pore size (11.33 nm) and surface area (82.41nullm2/g) as well as many HA functional groups, it provided multiple hydrophobic adsorption sites for dissolved Phe, which was conducive to competitive adsorption with DOC in the overlying water. In contrast to that adsorbed by DOC, the average proportion of dissolved Phe adsorbed by HA-ATP reached 90.55%, which reduced the dissolved Phe concentration in the overlying water. Furthermore, even though the particulate Phe was resuspended by crab bioturbation, HA-ATP immobilized particulate Phe due to its capacity to inhibit desorption, which achieved the goal of reducing the Phe concentration in the overlying water. This result was confirmed by research on the adsorption-desorption characteristics of HA-ATP. This research provides an environmentally friendly in situ remediation method for reducing agricultural environmental risks and improving rice crop quality. [Display omitted] • Modified attapulgite was prepared by hot acid modification with humic acid. • Crab bioturbation disrupted the Phe distribution balance between paddy soil and overlying water. • The adsorption efficiency of released dissolved and particulate Phe reached 91.91% and 36.38%. • HA-ATP and DOC competitively adsorbed dissolved Phe in overlying water. • HA-ATP immobilized particulate Phe in overlying water during resuspension. [ABSTRACT FROM AUTHOR]

Z-scheme anatase/rutile TiO 2 /g-C 3 N 4 hybrids (denoted as LTARCN-x, x represents calcination temperature) were designed and synthesized by growing TiO 2 nanorods on the surface of g-C 3 N 4 utilizing impregnation-calcination method. Furthermore, through the etched effect of hydrochloric acid and calcination treatment, the as-prepared LTARCN-x possessed abundant pore structure and larger surface area, and the surface area of LTARCN-425 was 8.5 times than that of bulk g-C 3 N 4. Meanwhile, the g-C 3 N 4 would play a role of carrier to prevent from the aggregation of TiO 2 nanorods. In addition, under visible light irradiation, the Z-scheme heterostructure would be constructed between the rutile TiO 2 nanorod and g-C 3 N 4 nanosheet, respectively. The optimized photocatalyst LTARCN-425 exhibited a preferable activity, the photocatalytic hydrogen production rate of LTARCN-425 was about 1031 μmol g−1 h−1, and it was about 6.3 and 13.6 times than that of g-C 3 N 4 and TiO 2 , respectively. Moreover, the photocatalytic mechanism of the hydrogen production was studied intensively via designing fluorescent probe, Pt and PbO 2 deposition experiment, and the characterizations of EPR, TEM, HRTEM and XPS. [ABSTRACT FROM AUTHOR]

Volume resistivity of polymer dielectrics reduces significantly with the increase of temperature. As a result, in direct current (DC) power apparatus or electronic device, temperature gradient over the material can result in considerable electric field distortion which greatly threats the polymer insulation. Advanced ceramic dielectrics are promising to be alternative to polymer insulation to deal with this issue. In this paper, Al 2 O 3 and Si 3 N 4 ceramic materials with different ion doping concentrations have been manufactured. Temperature dependent resistivity characteristics of the ceramics are obtained and compared with typical polymer dielectrics. Conduction models of the ceramic dielectrics are applied to understand their temperature dependent resistivity and its modulating mechanism. Effect of ion doping on the temperature dependent resistivity has been obtained and analyzed which agrees well with their charge trapping property acquired by thermal stimulation depolarization current measurement, based on which the method to modulate the temperature stability of material resistivity have been proposed. Finally, a comprehensive comparison between ceramics and polymers in high voltage DC applications have been made which further proves the advantage of ceramic dielectrics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Combining rice-crab coculture and bioaugmentation improved phenanthrene degradation. • Bioaugmentation changed the soil microbial community structure. • Crab bioturbation promotes the secretion of rice root exudates. • Pseudomonas sp. was positively correlated with some PGPRs. • The strategy achieves "remediation while production" in rice paddies. Polycyclic aromatic hydrocarbons (PAHs) are persistent and harmful pollutants with high priority concern in agricultural fields. This work constructed a rice-crab coculture and bioaugmentation (RCM) system to remediate phenanthrene (a model PAH) contamination in rice fields. The results showed that RCM had a higher remediation performance of phenanthrene in rice paddy compared with rice cultivation alone, microbial addition alone, and crab-rice coculture, reaching a remediation efficiency of 88.92 % in 42 d. The concentration of phenanthrene in the rice plants decreased to 6.58 mg/kg, and its bioconcentration effect was efficiently inhibited in the RCM system. In addition, some low molecular weight organic acids of rice root increased by 12.87 %∼73.87 %, and some amino acids increased by 140 %∼1150 % in RCM. Bioturbation of crabs improves soil aeration structure and microbial migration, and adding Pseudomonas promoted the proliferation of some plant growth-promoting rhizobacteria (PGPRs), which facilitated the degradation of phenanthrene. This coupling rice-crab coculture with bioaugmentation had favorable effects on soil enzyme activity, microbial community structure, and PAH degradation genes in paddy fields, enhancing the removal of and resistance to PAH contamination in paddy fields and providing new strategies for achieving a balance between production and remediation in contaminated paddy fields. [ABSTRACT FROM AUTHOR]

The effect of NaCl deposition on the deformation and fracture behavior during the cycle loading of dwell fatigue of Ti-6Al-4V alloy at 500 °C was investigated. Experimental results show that the hot corrosion reduces the dwell fatigue life of the alloy by up to 79 % compared with the bare (without salt) sample, and the degree of hot corrosion damage increase with the decrease of dwell stress. Comprehensive microstructural analysis suggests that the reduction of dwell fatigue life of the salt-coated sample is related to the crack initiation from surface corrosion pits/spalling pits and rapid crack propagation. Moreover, hot corrosion and creep damage are considered to exist competitive relationship during the failure process. • The hot corrosion-dwell fatigue interaction mechanism of Ti-6Al-4V alloy at 500 °C was investigated in detail. • The degree of hot corrosion damage increase with the decrease of dwell stress. • Hot corrosion severely affects the second and third stages deformation and shorten the dwell fatigue life. • Hot corrosion and creep damage are considered to exist competitive relationship during the failure process. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulation was employed to analyze the effects of different wax contents and molecular chain lengths on the wax deposition behavior in crude oil systems and the mechanism. The results show that the wax deposition on the iron surface occurs via a three-layer adsorption process driven by van der Waals (vdW) forces. In addition, there are four important stages in the process of crude oil deposition on iron surfaces. The first stage involves the diffusion of crude oil molecules onto the iron surface, the second involves their adsorption onto the solid surface and parallel alignment with the surface, and the third and fourth stages involve the formation of floccules through intermolecular interactions and bridging between the deposited layer adsorbed on the solid surface and the crude oil system. For different wax contents and molecular chain lengths, the wax deposition process is similar to crude oil systems, and the thicknesses of the deposited layers on the iron surface were similar. The primary contribution to the interaction energy between crude oil molecules and the iron surfaces is from vdW effects. As the crude oil system's wax content and molecular chain length increase, the interactions between crude oil molecules and the iron surface are strengthened, and these interactions are further enhanced as more crude oil molecules accumulate in the deposited layer. The results of the study may provide theoretical support for an in-depth understanding of the wax deposition process. [Display omitted] • The wax deposition behavior in crude oil systems and the mechanism are investigated. • The deposition of wax on iron surfaces is a three-layer adsorption process driven by van der Waals forces. • There are four stages in the process of crude oil deposition on iron surfaces. [ABSTRACT FROM AUTHOR]

• A flexible concentrated solar energy wireless transmission system was developed. • It uses the space sunlight to overcome intermittency of the solar energy application. • Optimal energy transmission modelling and experimental validation was conducted. • Maximum transmitter energy transmission efficiency of 52.0% was obtained experimentally. • Power/weight ratio of the system could be increased by 17.0% by comparing parallels. Solar energy in space is more intensive and continuous compared to that on the Earth, and thus, is encouraged by governments across the world to be utilized for human beings. The continuity of the space sunlight has a great potential to overcome the bottleneck of the variability and intermittency in time and space for ground-based solar energy applications. Space solar power station (SSPS) is known as intermedia that can harvest the space solar energy and transmit it wirelessly to the end-user. However, the current wireless energy transmission via microwave or laser suffers from low energy transmission efficiency because of excessive energy conversion processes. Wireless energy transmission via sunlight without any intermediate energy conversion process was proposed previously theoretically for high energy transmission efficiency, but it also lacks practicability due to heavyweight and inflexibility. Therefore, although promising, practical sunlight-based wireless energy transmission proposals have not ever been presented. Here, through component and structure optimizations in theoretical and experimental approaches, a novel and more practical concentrated solar energy wireless transmission system that transmits the harvested sunlight via lightweight optical fibers is proposed in this paper. It uses a Fresnel lens to collect concentrated solar energy and then, the utilized optical fiber can steer the collected energy to the collimator flexibly. At last, a parallel sunlight beam can be emitted from the collimator to the target end-user. Results show that the transmitter efficiency versus optical fiber length exhibited a linear relationship from both theoretical and experimental approaches. the cloud effect harmed the energy transmission. A maximum transmitter energy transmission efficiency of 52.0% could be attained experimentally. Compared with the performance in the no-cloud condition, the gained voltage could be declined by 37% ∼ 48%. The bending of the optical fiber seemed to not affect much on the energy transmission performance, which guarantees a flexible energy transmission. Besides, the power/weight ratio was increased by 17.0% compared to its counterpart. The innovation of this paper is to reduce the gap between theoretical and practical feasibilities for the proposed system. This paper experimentally demonstrates the feasibility of a wireless concentrated solar energy transmission technology, which promotes the application of SSPS and related aerospace applications. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) are universally used in diverse fields, but the use and treatment of various commodities will adversely affect the human health. Therefore, the recovery and immobilization of AgNPs and AuNPs from wastewater has important economic and social benefits. The ordered macro-microporous ZIF-67 single crystal (SOM-ZIF-67) was prepared by double solvent-assisted strategy. It was used as an adsorbent to remove precious metal pollutants, AuNPs and AgNPs. Under the optimal experimental conditions, the adsorption process of nanoparticles on SOM-ZIF-67 conformed to the pseudo-second-order kinetics. The theoretical maximum adsorption capacity of SOM-ZIF-67 towards AgNPs and AuNPs was 1250 mg g−1 and 2000 mg g−1, respectively. Through some characterization methods, it can be inferred that the adsorption mechanism might include ion-dipole interaction, metal-ligand interaction, and hydrogen bond, chelation and ion exchange between AgNPs/AuNPs and nitrogen and oxygen atom, and reduction etc. Furthermore, the interpenetrating macropores and micropores of SOM-ZIF-67 further promoting the adsorption capacity. Meanwhile, after the adsorption, the composite material (SOM-ZIF-67@AgNPs or SOM-ZIF-67@AuNPs) was developed as a new kind of heterogeneous catalyst that had good catalytic activity and cycle catalytic performance for 4-nitrophenol in the presence of NaBH 4. At last, the adsorbent and catalyst could be regenerated. Simultaneously recycling of precious noble metal was also possible. Thus, the prepared SOM-ZIF-67 was a potential green adsorbent for the removal and recovery of precious metal nanoparticles. The secondary utilization as an effective catalyst would elaborate the sustainability of the method. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of high-performance electrochemical energy storage device is important for addressing energy shortage issues. As one of the next-generation energy storage devices, supercapacitor (SCs) material and their composite designs have gained increased attention in recent years. Herein, the CNT@MoS 2 /PDDA/PMo 12 nanocomposite, was assembled via PDDA-assisted (PDDA is poly(dimethyldiallylammonium chloride)) synthesis strategy. The positively charged polyelectrolyte can interact with two negatively charged components, phosphomolybdic acid (PMo 12) and CNT@MoS 2 (CNT referred to multi-walled carbon nanotubes, and MoS 2 referred to molybdenum disulfide) through electrostatic interaction. PMo 12 has uniformly attracted on the surface of the ultrathin MoS 2 nanosheets-modified CNT, which endowed the nanocomposite with a fast electron transport efficiency, enrich charge storage and multi-electron transfer capabilities. As a symmetric supercapacitor system, this composite exhibited a high rate specific capacitance of 110 F g−1 at 0.5 A g−1 and an energy density of 15.27 W h kg−1 at a power density of 152 W kg−1. Moreover, an excellent cycle performance with 89% specific capacitance after 10000 charge-discharge cycles was obtained. • The CNT@MoS 2 /PDDA/PMo 12 nanocomposite was synthesized via a PDDA-assisted strategy. • The composite showed high specific capacitance and energy density compared with other MoS 2 -CNT/GO or POMs-based materials. • The nanocomposite has great cycling stability even after long cycles. • The synergistic effect was realized by CNT, MoS 2 and PMo 12 components. [ABSTRACT FROM AUTHOR]