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Graphite is a widely used oxygen impurity-removing additive and a property-tuning second phase for diboride and carbide-based ultrahigh temperature ceramics (UHTCs). In recent years, high-entropy diboride (HEB) ceramics have attracted much attention for the development of better UHTCs. However, oxide impurity generally inhibits their densification and harms their properties. Here, (Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2)B 2 ceramics added with different contents of graphite (HEB- x C, x = 0, 1, 2.5, 5, 10, 20 vol%) were prepared by spark plasma sintering. It was found that the added graphite acted as an oxygen-removing agent and the oxide impurity phase t -(Zr, Hf)O 2 was converted to the (Hf, Ta)C-based solid solution carbide. With the increase in graphite content, the relative density increased from 89.4% for HEB-0 C to 100% for HEB-10 C. Based on the evaluated properties of the prepared specimens, including Young's modulus, hardness, toughness, and thermal conductivity, the added graphite with an optimized content is important for a given started powder and processing to achieve good and balanced material properties. [ABSTRACT FROM AUTHOR]

In the preparation process for advanced ceramics, how to reduce the sintering temperature, shorten the processing time and refine grains is the key to obtaining high-performance ceramic materials. The flash sintering (FS) provides an effective method to solve this issue. Here, (Zr + Ta) co-doped TiO 2 colossal permittivity ceramics were successfully fabricated by conventional sintering (CS) and flash sintering under electric fields from 500 V/cm to 800 V/cm. The flash behavior, sintered crystal structure and microstructure, dielectric properties, and varistor characteristics were systematically investigated. The effects of the applied electric fields on the above behaviors were discussed. The results show that flash sintering can reduce the sintering temperature by 200 °C, decrease the processing time by 10 times and reduce grain sizes in TiO 2 ceramics. All sintered samples were single rutile structures. Flash sintering led to similar electrical properties to conventional sintering. In the flash-sintered samples, with increasing the electric field, the permittivity of co-doped TiO 2 ceramics increased at a frequency of 103–104 Hz. The flash-sintered sample under an electric field of 800 V/cm possessed the best comprehensive properties, a dielectric permittivity of >105, a dielectric loss of ∼0.77 at 103 Hz, and a nonlinear coefficient of 5.2. [ABSTRACT FROM AUTHOR]

Design of heterogeneous catalyst to achieve efficient conversion of biomass to high added-value chemicals is still very attractive. Herein, taking industrially important selective hydrogenation of furfural to furfuryl alcohol as an example, the designed amorphized HA zeolite encapsulation of platinum clusters (denoted as Pt@HA) exhibited excellent catalytic selectivity at totally conversion of the reactant furfural, along with good reusability and poison resistance ability. The selected amorphized HA zeolite with very small pore size constrained the reactant furfural to be reacted through hydrogen spillover process at zeolite surface, instead of to be adsorbed and activated onto Pt surface. Resulting from the stronger interaction between nucleophilic oxygen atom of aldehyde group and acid site at HA zeolite surface than that of furan ring group, furfural preferred to adsorb onto Pt@HA surface with the end of aldehyde group rather than the end of furan ring group, thus facilitating the spilled H atom to react with aldehyde group to give desired furfuryl alcohol product exclusively. [Display omitted] • Pt@HA exhibited remarkable catalytic property in hydrogenation of furfural to furfuryl alcohol via hydrogen spillover. • Spillover process disfavored activation of aldehyde group and furan ring simultaneously in one furfural molecule. • Acid sites on HA zeolite surface promoted adsorption of aldehyde group to facilitate its hydrogenation process. [ABSTRACT FROM AUTHOR]

In the offshore petroleum industry, polymer-containing oily sludge (PCOS) hinders oil extraction and causes tremendous hazards to the marine ecological environment. In this paper, an effective pretreatment method is proposed to break the adhesive structure of PCOS, and the experiments of supercritical water gasification are carried out under the influencing factors including residence time (5–30 min) and temperature (400–750 °C) in batch reactors. The increase of time and temperature all show great promoting effects on gas production. Polycyclic aromatic hydrocarbons, including naphthalene and phenanthrene, are considered as the main obstacles for a complete gasification. Carbon gasification efficiency (CE) reaches maximum of 95.82% at 750 °C, 23 MPa for 30 min, while naphthalene makes up 70% of the organic compounds in residual liquid products. The highest hydrogen yield of 19.79 (mol H 2 /kg of PCOS) is observed in 750 °C for 25 min. A simplified reaction pathway is presented to describe the gaseous products (H 2 , CO, CO 2 , CH 4). Two intermediates are defined for describing the reaction process bases on the exhaustive study on organic matters in residual liquid products. The results show that the calculated data and the experimental data have a high degree of fit and tar formation reaction is finished within 10 min. [Display omitted] • Utilization of polymer-containing oily sludge via supercritical water gasification. • Optimal gasification condition is obtained. • Reaction mechanism of gasification is discussed. • Tar formation reaction can be finished within 10 min in quartz tubes. [ABSTRACT FROM AUTHOR]

With the development of autonomous driving, ensuring pedestrian safety has become a hot research topic. The traditional pedestrian crossing behavior research mostly track and predict pedestrian crossing from the view of vehicles, but do not have in-depth research on the impact of other elements in the traffic scene. This paper proposes a method for analyzing pedestrian crossing behavior based on roadside equipment for specific road sections. First, a pedestrian awareness-based social force model (PASFM) is proposed by introducing the factors that influence pedestrian crossing decisions in traffic scenarios into the social force model (SFM), including zebra crossings, fellow walkers and vehicles. To explore the psychological state of vehicles and pedestrians when they interact, evolutionary game theory is used to simulate the psychological characteristics of pedestrians when they encounter vehicles, and then reflect in the changes of the desired speed. Then Centralized Unscented Kalman Filter (CUKF) is proposed to complete the whole process of tracking and predicting the motion state of pedestrian crossing behavior, which uses PASFM as its prediction process. Finally, simulations and experiments are designed to show the effectiveness of our methods. Results show that the proposed method performs better during pedestrian tracking and can predict their crossing behavior to a certain extent. [ABSTRACT FROM AUTHOR]

• A fractal model for the soil–water characteristic curve of Hunan clay was derived. • A fractal model for nonlinear seepage of saturated clay was established. • The model allows for easy computation and prediction of continuous permeation. • The prediction remains accurate even in soil with high dry density. It is crucial to investigate nonlinear seepage phenomena in low-permeability soils. Currently, empirical formulas account for the majority of nonlinear seepage model formulations. Some theoretical prediction models have been proposed; however, they tend to be computationally complex, and their predictive performance must be enhanced. Considered an indirect indicator, the soil–water characteristic curve reflects the permeation channels of soil pores of varying diameters. A nonlinear seepage model for saturated clay has been devised, taking into account the initial hydraulic gradient of microscopic seepage channels. This paper derives and solves the fractal dimension of the soil–water characteristic curve fractal model and establishes a new nonlinear seepage fractal model for saturated clay under various hydraulic gradients. The new seepage fractal model proposed in this paper is used to predict the seepage velocity of saturated Hunan clay under various hydraulic gradients and is compared to the results of its nonlinear seepage test. Overall, the results indicate that the predicted values of the seepage fractal model presented in this paper closely match the experimental values, and the accuracy of the prediction of the seepage velocity of saturated clay with a higher dry density exceeds that of present theoretical models. [ABSTRACT FROM AUTHOR]

Abstract To develop a novel lignin-based highly efficient nitrogen fertilizer, the amination of the biorefinery technical lignin was conducted by Mannich reaction synergy with phenolation pretreatment. Subsequently, the structural transformations of lignin samples and the reaction mechanism were investigated in detail. The soil column leaching experiment was also performed to research the nitrogen release behavior of aminated lignin in soil. The results indicated that the amounts of active sites in lignin were significantly increased to 8.26 mmol/g from the original 2.91 mmol/g by phenolation. In addition, the Mannich reaction was highly selective for occurring at ortho - and para -positions of phenolic hydroxyl groups in the phenolated lignin, in which the latter was favored. Moreover, the nitrogen content in the aminated lignin was highly depended on the types of amination reagent instead of the proportion of reactants in this study. Under an optimal condition, aminated lignin with a high nitrogen content (10.13%) and low C/N ratio (6.08) could be obtained. Besides, it was especially noteworthy that the prepared APL in this study has a favorable nitrogen release behavior in soil. Thus, it is believed that these aminated lignin derivatives could be used for the preparation of various lignin-based highly efficient nitrogen fertilizer. Highlights • The chemical reactivity of lignin was significantly improved by phenolation. • The nitrogen content of APL was highly depended on the types of amination reagent. • Ethanediamine is regarded as the most favorable among these selected amination reagents. • An optimum chemosynthesis condition of high N-containing APL was obtained. • A new approach was developed to prepare lignin-based highly efficient fertilizer. [ABSTRACT FROM AUTHOR]

Highlights • The aluminium foam sandwich was fabricated using friction stir welding. • No undesirable interface reaction existed among the face sheets and the foam core. • AFS prepared through FSW possessed high flexural strength and impact resistance. • The AFS possessed good sound absorption and insulation performance. Abstract The aluminium foam sandwich (AFS), prepared through the traditional adhesive or brazing methods, usually exhibits a low flexural strength due to the poor combination among the face sheets and the aluminium foam core. In this work, a new method, named friction stir welding (FSW), was utilized to fabricate AFS. The results demonstrated that the joining of the face sheets and aluminium foam was achieved through the plasticized metal flow. In addition, the AFS prepared through FSW possessed high flexural strength and impact resistance, as well as good sound absorption and reduction performance. This demonstrated that the FSW was a good method to prepare AFS. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Spontaneous symmetry breaking has revolutionized the understanding in numerous fields of modern physics. Here, we theoretically demonstrate the spontaneous time-reversal symmetry breaking in a cavity quantum electrodynamics system in which an atomic ensemble interacts coherently with a single resonant cavity mode. The interacting system can be effectively described by two coupled oscillators with positive and negative mass, when the two-level atoms are prepared in their excited states. The occurrence of symmetry breaking is controlled by the atomic detuning and the coupling to the cavity mode, which naturally divides the parameter space into the symmetry broken and symmetry unbroken phases. The two phases are separated by a spectral singularity, a so-called exceptional point, where the eigenstates of the Hamiltonian coalesce. When encircling the singularity in the parameter space, the quasi-adiabatic dynamics shows chiral mode switching which enables topological manipulation of quantum states. [ABSTRACT FROM AUTHOR]

Emergence of antibiotic-resistant bacteria constitutes an increasing threat to human health. For example, treatment options for Staphylococcus aureus infections is declining with the worldwide spreading of highly virulent community-associated methicillin-resistant S. aureus (CA-MRSA) strains. Anti-virulence therapy has been proposed as an alternative treatment strategy, as it typically involves inhibition of expression of virulence factors rather than direct bacterial killing, thereby attenuating the risk of resistance development. An intriguing target is the agr quorum-sensing system, which is a major inducer of virulence in CA-MRSA upon activation by agr -encoded staphylococcal autoinducing peptides (AIPs). In the present work a previously identified lactam hybrid analogue based on the marine depsipeptide solonamide B and the general structure of AIPs was investigated with respect to structure–function relationships. An array of 27 analogues exploring expansion of ring size, type of side chain, amino acid substitutions, and stereochemistry was designed and tested for AgrC-inhibitory activity. Interestingly, it was found that an analogue derived from the mirror image of the original hit proved to be the hitherto most efficient AgrC inhibitor resembling solonamide B in amino acid sequence. This and closely related compounds were 20- to 40-fold more potent in AgrC inhibition than the starting hit compound. [ABSTRACT FROM AUTHOR]

A variety of nucleic acid amplification techniques have been integrated into different detection methods to promote the development of sensitive and convenient analysis of nucleic acids. However, it is still in urgent need to develop amplified nucleic acid biosensors for the analysis of susceptible gene and even distinguishing single-base mismatched DNA in complex biological samples. Benefiting from the achieved detection strategies, here we boost isothermal nucleic acid amplification by resorting to enzyme amplification, and combine this two-stage amplification method with surface-enhanced Raman spectroscopy (SERS) to develop a signal-on nucleic acid detection platform. Due to the high cleavage efficiency of Exonuclease III (Exo III), a large amount of trigger DNA are produced to initiate multiple hybridization chain reaction circles. The product structure tagged with Tamra is then anchored onto the plasmonic SERS substrate and meanwhile enriched. It is demonstrated that this detection platform is sensitive toward the myocardial infarction disease related gene. A detection limit of 1 fM for the gene analysis in a linear relationship in the wide range from 1 fM to 10 nM is achieved, better than most of previous counterparts. Meanwhile, our developed detection platform exhibits a high selectivity for the target gene over mismatched analogues. Our strategy provides a robust tool for signal amplification of gene detection even in blood samples. [ABSTRACT FROM AUTHOR]

Carboxymethyl xylan- g -poly(propylene oxide) (CMX- g -PPO) was successfully synthesized by grafting poly(propylene oxide) chains onto xylan from bamboo using the Al(O i -Pr) 3 initiated ring-opening polymerization of propylene oxides, followed by carboxymethylation with sodium chloroacetate under microwave irradiation. The synthesized CMX- g -PPO was well characterized by FT-IR, 13 C NMR, and AFM. The AFM imaging showed that the average sizes of xylan were 422.1 × 67.4 × 1.2 nm, while the average sizes of grafting branches PPO were 128.0 × 38.5 × 5.1 nm, which firstly provided an irrefutable and visual evidence for the structure of grafted xylan at single molecular level. Subsequently, a serial of CMX- g -PPO/CS films were prepared without addition of any plasticizers. The surface morphologies, wettability, water vapor barrier properties, mechanical properties, and thermal stabilities of the obtained films were characterized and compared with those of the control films by AFM, contact angle, WVP, tensile testing, and TGA, respectively. [ABSTRACT FROM AUTHOR]

We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry–Perot resonance. [ABSTRACT FROM AUTHOR]

Highlights: [•] Microwave-assisted acid hydrolysis was performed at 90°C to produce XOS. [•] No sugar-degraded byproduct was detected in hydrolysates. [•] Acid concentration and reaction time were ascertained by response surface methodology. [•] The maximum XOS yield was achieved with 0.24M H2SO4 for 31min. [•] Acid concentration was a more significant coefficient in XOS production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gluten network goes through disassembly and repolymerization during processing. • β-sheets are positively associated with gluten polymerization and dough viscosity. • The stronger dough gluten inhibits starch pasting more significantly. • Covalent protein-starch interactions are found in strong-gluten dough. • Additional protein-starch complexes in dough matrix retard starch retrogradation. To clarify the detailed behaviors of protein, starch and interactions during complex dough processing, structural changes in dough protein and starch during continuous Mixolab processing were investigated using wheat near-isogenic lines carrying high-molecular-weight glutenin subunits 1Dx5 + 1Dy10 (5 + 10) or 1Dx2 + 1Dy12 (2 + 12) at the Glu-D1 locus. A more stable gluten network including disulfide bonds and hydrophobic interactions, was formed in the 5 + 10 dough before dough weakening at 53.5 °C, than in the 2 + 12 dough. Thereafter, thermo-mechanical treatment induced the depolymerization of gluten until starch gelatinization peak at 74.6 °C; however, from the peak to trough viscosity at 82.8 °C, additional monomeric proteins were incorporated into the repolymerized proteins characterized by increased disulfide bonds, hydrogen bonds, and β-sheets. Generally, the protein aggregates of 5 + 10 showed a higher degree of polymerization and better stability than those of 2 + 12 during dough processing, which significantly slowed starch gelatinization and recyclization. Moreover, stronger interactions between monomeric proteins and amylose/short-branch starch via glycosidic and hydrogen bonds were found in 5 + 10 dough during starch pasting and retrogradation. The findings demonstrate the feasibility of optimizing the texture and digestibility of wheat-based food products by regulating the behaviors and interactions of proteins and starch during dough processing. [ABSTRACT FROM AUTHOR]

The content of intermetallic compounds (IMCs) in friction stir lap welded (FSLW) dissimilar joints of Mg and Al alloys could be reduced by the addition of interlayer metal to improve the mechanical properties of the joints, while the underlying mechanism is still unclear. In this study, Cu and Ni powders are added as the interlayer materials into the FSLW joints of AZ31 Mg alloy and Al–Zn–Cu–Mg alloy, respectively. The types, sizes, and distributions of IMCs have been characterized, and the shear properties of the joints have been evaluated. Moreover, the mechanism underlying the influence of the interlayer metals on the evolution of IMCs in the joints and the effect of IMCs on the shear properties of the joints have been studied. The results showed that the order of phase formation in the joint without interlayer was Al 12 Mg 17 , Al 3 Mg 2 , MgZn 2 , CuMg 2 , Al 2 Cu, while the order of phase formation in the joint with added Cu interlayer was Al 2 Cu, CuMg 2 , AlCu, Al 12 Mg 17 , Al 3 Mg 2 , Cu 5 Zn 8 , and that in the joint with added Ni interlayer was Mg 2 Ni, Al 3 Ni, Al 3 Ni 2 , MgNi 2 , AlNi, Al 12 Mg 17 , Al 3 Mg 2 , MgZn 2 , Ni 3 Zn 22 , NiZn, Al 2 Cu. Due to the formed physical barrier and the mechanism of phase formation, the addition of interlayer metal effectively inhibited the formation of a Mg–Al phase. The bonding strengths between Mg–Cu, Al–Cu, Al–Ni, and Mg–Ni phases and matrix were higher than that between Mg–Al phase and matrix, which improved the shear properties of the joints with Cu and Ni interlayers. [ABSTRACT FROM AUTHOR]

• HMW-GSs 5 + 10 contributed to a more extensive and compact protein-starch complex. • More monomeric proteins were involved into gluten possessing subunits 5 + 10. • Subunits 5 + 10 can cause low starch gelatinization degree in dough matrix. • Subunits 2 + 12 contributed to a fragile gluten network with low thermal stability. • The ratio of β-sheets to α-helix was positively associated with dough consistency. Differences in Mixolab measurements of dough processing were examined using, as a base, flour from pure breeding, isogenic, wheat lines carrying either the high molecular weight glutenin subunits 5 + 10 or 2 + 12. Before dough pasting, subunits 5 + 10 tend to form a stable gluten network relying mainly on disulfide bonds and hydrogen bonds, but 2 + 12 flour was prone to generating fragile protein aggregates dominated by disulfide bonds and hydrophobicity. During dough pasting, a broader protein network rich in un-extractable polymeric proteins, disulfide bonds and β-sheets was formed in the dough with subunits 5 + 10, thus resulting in an extensive and compact protein-starch complex which was characterized by high thermal stability and low starch gelatinization, while in the dough of the 2 + 12 line, a porous protein-starch gel with fragmented protein aggregates was controlled by the combination of disulfide bonds, hydrophobicity and hydrogen bonds that facilitated the formation of antiparallel β-sheets. [ABSTRACT FROM AUTHOR]

Supercritical water gasification (SCWG) of oily sludge is a potential handling method for resource utilization and pollution reduction. Heavy metals (HMs) in oily sludge were assessed due to their threat to human health and environmental safety. This work investigated the distribution of four HMs (Cu, Zn, Ni and Cr) under different reaction conditions (550–700 °C, 1–60 min). The concentrations of HMs in liquid residues (LRs) decreased continuously at higher temperatures and longer residence times except for Ni. Besides, the concentrations of HMs in solid residues (SRs) increased after SCWG except for Zn, and they varied slightly under different conditions. Then, HMs in LRs and SRs were evaluated in terms of Nemerow index, geo-accumulation index and potential ecological risk. The results indicated that the pollution risks of HMs in LRs were minimum at 650 °C and 30 min, while that in SRs changed little. When Na 2 CO 3 was added, pollution risks changed slightly, but nearly complete stabilizations of Cu, Zn and Cr (96.2%, 84.2% and 98.6%) were achieved at 600 °C. Adding Na 2 CO 3 promoted the formation of aluminosilicate to combine with HMs and enhanced their stabilization notably. This work may demonstrate a promising clean way for oily sludge utilization and HMs stabilizing. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Hemicelluloses are types of plant cell wall polysaccharides, and the world''s second most abundant renewable polymers after cellulose in lignocellulosic materials. They represent a type of hetero-polysaccharide with complex structure containing glucose, xylose, mannose, galactose, arabinose, rhamnose, glucuronic acid, and galacturonic acid in various amounts, depending on the source. Hemicelluloses are usually bonded to other cell-wall components such as cellulose, cell-wall proteins, lignin, and phenolic compounds by covalent and hydrogen bonds, and by ionic and hydrophobic interactions. This paper provides a review on hemicelluloses from lignocellulosic materials, especially in regard to their isolation and purification methods, and bioconversion. Current isolation and purification strategies are summarized, including: alkali peroxide extraction, organic solvent extraction, steam explosion, ultrasound-assisted extraction, microwave-assisted extraction, column chromatography, and membrane separation. In addition, the bioconversion of hemicelluloses including pretreatment, enzymatic hydrolysis, and fermentation are discussed. [Copyright &y& Elsevier]

Abstract: Contract capacity setting for industrial consumer with self-owned generating units (SOGUs) is a highly discrete and nonlinear optimization problem considering expenditure on the electricity from the utility and operation costs of the SOGUs. This paper proposes an improved Taguchi method that combines existing Taguchi method and particle swarm optimization (PSO) algorithm to solve this problem. Taguchi method provides fast converging characteristics in searching the optimal solution through quality analysis in orthogonal matrices. The integrated PSO algorithm generates new solutions in the orthogonal matrices based on the searching experiences during the evolution process to further improve the quality of solution. To verify feasibility of the proposed method, the paper uses the real data obtained from a large optoelectronics factory in Taiwan. In comparison with the existing optimization methods, the proposed improved Taguchi method has superior performance as revealed in the numerical results in terms of the convergence process and the quality of solution obtained. [Copyright &y& Elsevier]

Abstract: Water and alkali-soluble polysaccharides, isolated by sequential extractions with distilled water, 0.5% and 1% NaOH, 60% ethanol containing 1% NaOH, and 3%, 5% and 8% NaOH, were prepared at 60°C for 3h from dewaxed bamboo Phyllostachys incarnata Wen. The yields of the seven fractions together accounted for 80.1% of total available hemicellulosic polysaccharides. Sugar composition studies showed that the water-soluble polysaccharides consisted mainly of glucose units, while xylose, arabinose and glucuronic acid were the major sugars in alkali-soluble hemicelluloses. Moreover, the molecular weights of these polymers varied between 3760 and 36,000g/mol as revealed by GPC. Furthermore, the structure of the hemicellulosic fraction extracted with 3% NaOH was determined by 1H and 13C NMR spectroscopy along with 2D HSQC. It was found that the bamboo hemicelluloses were O-acetyl-(4-O-methylglucurono)-arabinoxylans, and the structural element could be identified as below: 1,4-β-D-[2-O-Ac][2,3-di-O-Ac][4-O-Me-α-D-GlcpA-(1→2)][α-L-Araf-(1→2)(1→3)]-xylp. [Copyright &y& Elsevier]

Abstract: We present a comparative study on the acoustic tunneling through artificial periodical composites, from phononic crystals to acoustic metamaterials. We find that the features of the acoustic tunneling are closely related with the origins of band gaps. In particular, the band gap associated with the negative effective material parameter in the metamaterial results in a better analog of the tunneling effect to the quantum system. [Copyright &y& Elsevier]

Abstract: We investigated the balance of free radicals in retinas at various time points after chronically elevating intraocular pressures in rats. The left eyes of female Wistar rats were divided into five intraocular pressure elevation (IOPE) subgroups after cauterization of three episcleral veins (1 day, 3 days, 1 week, 3 weeks, and 5 weeks) and time-related sham controls. Chemiluminescence levels were examined in isolated retinas. The nitroblue tetrazolium (NBT) incubation method was also performed to confirm the superoxide expression. The activities of antioxidant enzymes and lipid peroxides in isolated retinas were detected by spectrophotometry. In the IOPE group, the intraocular pressure after cauterization was around 22–30 mm Hg; chemiluminescence levels of isolated retinas were significantly elevated on day 3 and week 1; there were more NBT-positive retinal ganglion cells on day 1 and day 3; lipid peroxidation also increased significantly from day 1 and came back to the baseline on week 5; the activities of superoxide dismutases and catalase rose on week 1. Intraocular pressure elevation was shown to change the free radical balance. We suggest that free radicals and their oxidative stresses may play a role in the early stage of glaucoma in causing retinal ganglion cell death in our rat model. [Copyright &y& Elsevier]

At present, the effect of the microstructure of friction stir lap welded (FSLW) dissimilar joints of Mg and Al alloys on fatigue crack initiation and propagation is not clear. In this article, the effects of the microstructure of FSLW dissimilar joints of AZ31 Mg and Al–Zn–Cu–Mg alloys are studied. The grain orientations of the crack initiation and propagation region were characterized by electron backscattering diffraction analysis. And the models for fatigue crack propagation in the different grain orientations were established. Based on the above experimental results, the initiation mechanisms of fatigue cracks were clarified, and the effects of grain orientations on crack propagation were revealed. The results showed that the crack initiation was caused by the simultaneous activation of the (0002, 2 1 ¯ 1 ¯ 0] basal slip and twinning in various directions by fatigue loading. The direction of crack propagation was dominated by the (0002)[ 2 ¯ 110] basal slip with (1 ¯ 012)[ 1 ¯ 01 1 ¯ ] twinning adjusting in the crack propagation zone. The cyclic effect of concentration and release of stress on the activation and termination of twins was the main reason for the zigzag path of crack propagation. • (0002, 2 1 ¯ 1 ¯ 0] basal slip and twinning in various directions caused crack initiation. • Crack propagation models with the different grain orientations were established. • Activation and termination of twins caused zigzag path during crack propagation. [ABSTRACT FROM AUTHOR]

In recent years, hydrogels with antifouling properties and good biocompatibility have attracted great attention in bio-devices, but most of them are lack of eminent mechanical properties that limit their practical application greatly. In this work, a newly hybrid ion-covalent cross-linked double network (DN) hydrogels with excellent antifouling as well as mechanical properties were prepared by a simple one-pot method based on sodium alginate and a kind of antifouling material, N -hydroxyethyl acrylamide (HEAA). The DN hydrogel have excellent mechanical properties, including high tensile strength (1.32 MPa), high elastic modulus (0.31 MPa) and preeminent fatigue resistance. Besides, the DN hydrogel have good antifouling properties suggested by protein adsorption and cell adhesion experiments. In addition, they also exhibit highly in vitro compatibility. These properties make the DN hydrogels suitable for application in different fields, such as tissue scaffolds, implantable devices and so on. • The PHEAA/SA-Ca2+ DN hydrogels possess high tensile strength, high elastic modulus and excellent fatigue resistance. • The hydrogels can resist non-specific proteins adsorption and cells adhesion. • The hydrogels have highly in vitro biocompatibility. [ABSTRACT FROM AUTHOR]

The formation mechanism of intermetallic compounds (IMCs) during dissimilar friction stir lap welding (FSLW) of Mg and Al alloys, as well as the effects of IMCs on the shearing properties of FSLW joints, are still ambiguous and require clarification. In this study, FSLW dissimilar joints of AZ31 Mg alloys and Al–Zn–Cu–Mg alloys are investigated to clarify the formation mechanism of IMCs and their effect on the joint strength. Microstructures and shearing properties of the joints are characterized. The results showed that new phases of Al 12 Mg 17 , Al 3 Mg 2 , MgZn 2 , and Al 2 Cu are generated at the welding interface, and the original Cu 2 Mg phase is dissolved into the Al matrix during FSLW. Furthermore, the formation sequence of IMCs in the same binary system is affected by the effective enthalpy of formation, while it is related to the element concentrations in different binary systems. The order of IMC formation is as follows: Al 12 Mg 17 , Al 3 Mg 2 , MgZn 2 , and Al 2 Cu. During shearing deformation of the FSLW joint, the crack is initiated at the hook zone in the retreading side and propagated along the welding interface, where IMCs aggregate and the strain concentrates. The small lattice mismatch between the IMCs and the matrix improves their interfacial bonding strength, which increases in the following order: Al 12 Mg 17 and Al, Al 12 Mg 17 and Mg, Al 3 Mg 2 and Al, Al 3 Mg 2 and Mg, MgZn 2 and Al, MgZn 2 and Mg, Al 2 Cu and Al, Al 2 Cu and Mg, Cu 2 Mg and Mg, and Cu 2 Mg and Al. • Thermodynamics and atomic collision affected formation mechanism of IMCs. • Formation sequence of IMCs during FSLW was: Al 12 Mg 17 , Al 3 Mg 2 , MgZn 2 and Al 2 Cu. • Effects of IMCs on joint strength were analyzed by atomic lattice mismatch. • High lattice mismatches between matrices and Al 12 Mg 17 reduced joint strength. [ABSTRACT FROM AUTHOR]

• GP/SNF membrane was fabricated by renewable biomass resources. • Novel GP/SNF membranes were fabricated for oil-water emulsions separation. • GP/SNF membranes presented good mechanical property and thermal stability. • GP/SNF membrane is the candidate in oil/water separation practical application. • GP/SNF-20 membrane presented the highest permeation fluxes. Oil contaminant in water has become serious environmental pollution that causes danger for human health. Membrane separation technology is considered as one of the most efficient treatment for oily wastewater. Here, we report that the renewable hydrophobic membranes for oil-water emulsions separation were fabricated by incorporating gutta percha (GP) into silylated nanofibers (SNF) from herbal residues. The obtained membranes were characterized by Raman spectra, XPS, XRD, SEM, AFM, TGA, and DSC. Subsequently, the effects of gutta percha loading levels on membrane hydrophobicity, mechanical property, water vapor permeability, and efficacy of oil-water emulsions separation were investigated. Incorporation of GP into SNF is benefit for enhancing hydrophobicity, thermal stability, and mechanical performance. More importantly, these GP/SNF membranes exhibited high-efficiency separation ability for oil-water emulsions. Especially, GP/SNF-20 membrane presented the highest permeation fluxes of 3624, 3308, 3186 and 2866 L m−2 h−1 W−1 for separation of petroleum ether, dichloromethane, toluene, and cyclohexane-in-water emulsions, respectively. [ABSTRACT FROM AUTHOR]

• We detected a total of 14,215 circRNAs in AF and healthy controls. • We identified 20 upregulated and 3 downregulated circRNAs in AF. • Hsa_circ_0003965 was associated with glucagon signaling pathway. • Hsa_circ_0000075 and hsa_circ_0082096 may participate in AF via TGF-beta signaling. Atrial fibrillation (AF) is an abnormal heart rhythm characterized by rapid and irregular beating of the atria. The non-coding RNAs (ncRNAs) have attracted much attention of AF researchers, as they play a critical role in the transcriptional and post-transcriptional regulation, which could greatly benefit the interpretation of the pathogenesis of AF. However, circRNAs, as a special member of the ncRNAs, and their role in the pathogenesis of AF is less understood. In the present study, we detected a total of 14,215 circRNAs in AF patients and healthy controls. Differential expression analysis of these circRNAs revealed 20 upregulated and 3 downregulated circRNAs, which were differentially expressed in both left and right atrial appendages. The association analysis of the AF-related circRNAs and their parental genes revealed that hsa_circ_0003965 had significantly negative correlation with its parental gene TMEM245 (PCC = −0.51), suggesting that the dysregulation of hsa_circ_0003965 was not regulated by the transcription of its parental gene, but could be associated with glucagon signaling pathway. The competing endogenous RNA (ceRNA) network analysis revealed two upregulated genes, IFNG and GDF7, and one downregulated gene, BMP7, all of which were involved in TGF-beta signaling pathway, which further suggested that these circRNAs, namely hsa_circ_0000075 and hsa_circ_0082096, participated in the AF pathogenesis via TGF-beta signaling pathway. Consistently, TGF-beta signaling pathway was a well-recognized player for its association with atrial fibrosis in AF. In summary, we aimed to discover and provide key circRNAs involved in AF for AF-related researchers, which had the potential to greatly improve our understanding of the underlying mechanism behind circRNAs and AF. [ABSTRACT FROM AUTHOR]

The dense bulk ZnO–Bi 2 O 3 based varistor ceramics were obtained via flash sintering at a low temperature. The effect of different additives such as Cr 2 O 3 , MnO 2 and Co 2 O 3 on flash sintering onset temperature and incubation time was investigated. All samples were fabricated under a constant heating rate with a DC electric field of 300 V/cm. At the same time, the onset temperature of all samples was below 750 °C. ZnO–Bi 2 O 3 –Cr 2 O 3 was fabricated at the lowest temperature of 704 °C and the shortest incubation time among the specimens by a constant heating rate flash sintering. In addition, the nonlinear current-voltage and dielectric properties were analyzed. ZnO–Bi 2 O 3 –Co 2 O 3 varistor ceramics showed the highest nonlinear coefficient of 39.5 and the lowest leakage current of 2.64 μA. Therefore, flash sintering is a promising method for preparation of ZnO varistor ceramics efficiently. [ABSTRACT FROM AUTHOR]

Biomass supercritical water gasification is clean and renewable, which can convert biomass into hydrogen rich gas. Previous studies indicated that external recycle of liquid residual could improve gas yield and gasification efficiency. However, the influence mechanism of external recycle on energy and exergy efficiency is complicated and theoretical model for system optimization is insufficient. Thermodynamic model of external recycle of liquid residual was built in this paper. Exergy efficiency of the main components and exergy loss distribution were specified and the result showed that exergy loss of reactor and preheater accounted for 26.06% and 35.88% of the total exergy loss, which were the main exergy loss sources. Effective ways to reduce exergy loss of components with large exergy loss and to improve energy and exergy efficiency of the system were proposed. Moreover, life cycle assessment of biomass gasification process was carried out. The results indicated that the increase of gasification temperature, pressure and external recycle flow rate of liquid residual and decrease of biomass concentration could improve energy and exergy efficiency of the system. Energy and exergy efficiency reached 63.67% and 48.29% respectively at the condition of gasification temperature of 560 °C, pressure of 25 MPa, recycle flow ratio of 32.43%, biomass concentration of 2.78%. Besides, the increase of gasification temperature and decrease of biomass slurry concentration and pressure could decrease GWP. Thermodynamics and LCA analysis of biomass supercritical water gasification using external recycle system was conducted. Image 103 • Material, mass and energy balance of the system and each component was achieved. • Component with largest exergy loss was found and solutions were proposed. • Approaches to improve energy and exergy efficiency of the system were proposed. • LCA of biomass gasification in SCW was conducted. • Highest energy and exergy efficiency reached 63.67% and 48.29% respectively. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of heat-moisture treatment (HMT) on the in vitro digestibility of recombinant wheat flours characterizing by gluten proteins differ in glutenin-gliadin ratio. Compared with the untreated flours in our previous study, HMT improved the digestion resistance of starch in flours with different glutenin-gliadin ratios. For the HMT strong-gluten flour, the proportional increase of glutenin led to an excessively strong and fragile gluten network that unstable under HMT, which weakened the wrapping of gluten network around starch granules and reduced the long- and short-range order of starch, resulting in the conversion of resistant starch (RS) and slowly digestible starch (SDS) to rapidly digestible starch (RDS); however, the quantitative increase of gliadin induced the conversion of SDS to RS due to the enhanced protein-starch interactions as well as the improved long- and short-range order of starch during HMT. For the HMT weak-gluten flour, the changes of glutenin-gliadin ratio aggravated the broken of protein network and starch granules during HMT, thus improving the starch digestibility in varying degrees. In conclusion, the relative crystallinity of starch mainly affected the content of resistant starch, while the content of slowly digestible starch was more influenced by protein-starch interactions. • Heat-moisture treatment promotes binding between protein and starch in flour. • Proportional increase of gliadin in strong-gluten flour reduces starch digestibility. • Starch digestibility is related to starch structure and protein-starch interactions. • Quantity of resistant starch is more related to the relative crystallinity of starch. • Protein-starch interactions promote the formation of slowly digestible starch. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The honeycomb carbon materials were prepared by using carbon hollow spheres. • The specific surface area of HCM is 1436.21 m2/g. • The maximum amount of Cr adsorbed by HCM is 332.53 mg/g. • HCM has good reusability performance. Abstract Hollow carbon spheres (HCSs) were prepared by a hydrothermal synthetic method using glucose as the raw material, and a honeycomb carbon material (HCM) was prepared by modifying these HCSs. The materials were characterized by SEM, TEM, BET, Raman spectroscopy, XPS, XRD, and elemental analysis. A large number of pores were observed in the HCM by SEM and TEM, and the specific surface area of the material, as determined by BET testing, was 1436.21 m2/g. The adsorption properties of the HCM were tested by a batch adsorption method. The maximum adsorption capacity of the HCM for Cr(VI) was 332.53 mg/g, and the performance was better than that of a similar materials. The kinetic thermodynamics and intraparticle diffusion models were fit, and it was found that the adsorption of Cr(VI) onto the honeycomb carbon was a spontaneous endothermic process. The regenerative adsorption experiments showed that the material had good regenerative abilities. [ABSTRACT FROM AUTHOR]

Abstract In this work, we evaluated the ability of Punica granatum sarcotesta lectin (PgTeL) to impair the growth and viability of the Staphylococcus aureus clinical isolates 8325–4 (non-resistant) and LAC USA300 (MRSA strain). The effects of this lectin on aggregating, hemolytic activity, biofilm-forming ability, and expression of virulence genes (hla , rnaIII , and spa) were also investigated. PgTeL showed antibacterial activity against 8325–4 and LAC USA300 strains by interfering with both the growth (MIC 50 of 6.25 and 12.5 μg/mL, respectively) and survival (MBC values of 25.0 and 50.0 μg/mL, respectively). Culture growth started only at the ninth (8325–4) and tenth (LAC USA300) hour in the presence of PgTeL at MIC 50 , while growth was detected since the first hour in the control. The lectin caused markedly altered cell morphology in both the strains. Although, at the MIC 50 , PgTeL caused structural alterations, most cells were still viable, while at the MBC it promoted cell injury and death. PgTeL showed anti-aggregation effect and exhibited antibiofilm activity against both the isolates. However, the lectin did not interfere with the hemolytic activity of LAC USA300 and with the expression of hla , rnaIII , and spa genes. In conclusion, PgTeL is a lectin with multiple inhibitory effects on S. aureus clinical isolates. Highlights • PgTeL showed antibacterial activity on S. aureus non-resistant (8325–4) and MRSA (LAC USA300) strains. • The lectin caused strong alterations of cell morphology for both strains. • PgTeL showed anti-aggregation effect displayed antibiofilm activity on both strains. • PgTeL did not interfere with the expression of hla , rnaIII and spa genes by S. aureus. [ABSTRACT FROM AUTHOR]

Real data often show that from appearance within-class similarity is relatively low and between-class similarity is relatively high, which could increase the difficulty of classification. To classify this kind of data effectively, we learn multiple classification criteria simultaneously, and make different classification criterion be applied to classify different data for the purpose of relieving difficulty of fitting this kind of data and class label only by using a single classifier. Considering that topic model can learn high-level semantic features of the original data, and that mixture of softmax model is an efficient and effective probabilistic ensemble classification method, we embed a mixture of softmax model into latent Dirichlet allocation model, and propose a supervised topic model, supervised latent Dirichlet allocation with a mixture of softmax , and its improved version, supervised latent Dirichlet allocation with a mixture of sparse softmax . Next, we give their parameter estimation algorithms based on variational Expectation Maximization (EM) method. Moreover, we give an approximation method to classify unseen data, and analyze the convergence of the parameter estimation algorithm. Finally, we demonstrate the effectiveness of the proposed models by comparing them with some recently proposed approaches on two real image datasets and one text dataset. The experimental results demonstrate the good performance of the proposed models. [ABSTRACT FROM AUTHOR]

• Pt@HA exhibited excellent catalytic selectivity in hydrogenation of quinoline via hydrogen spillover. • Spillover process discriminated the hydrogenation of pyridine and benzene moiety in quinoline molecule. • Hydroxyl groups on HA zeolite strengthened adsorption of pyridine moiety to facilitate its hydrogenation process. Hydrogen spillover has been widely used in heterogeneous catalysis, yet how to explore the potential of catalyst support to further promote catalytic function of hydrogen spillover has rarely been investigated. Herein, platinum encapsulated into amorphized HA zeolite (denoted as Pt@HA) with generated hydroxyl groups was used as model catalyst to study the role of HA zeolite support on the promotion of catalytic performance in hydrogenation of quinolines to tetrahydroquinolines. Benefiting from small pore size of amorphized HA zeolite to prevent direct interaction of quinoline with encapsulated platinum, Pt@HA showed good catalytic selectivity in this transformation through hydrogen spillover. This remarkable catalytic selectivity was resulted from the interaction of hydroxyl groups at surface of HA zeolite with pyridine moiety through the formation N H bond to facilitate adsorption to make much lower apparent activation energy of Pt@HA for hydrogenation of pyridine moiety than that of benzene moiety, thus exhibiting enhanced catalytic selectivity. [Display omitted] [ABSTRACT FROM AUTHOR]

Lignin is the most abundant renewable aromatic resource on the planet, and it may be exploited to make the controlled release fertilizers (CRFs) that aid in human sustainable agriculture. Many researches on lignin-based CRFs have been conducted in recent years because of their exceptional controlled-release qualities. Lignin-based physically impeded CRFs can be produced by absorbing or wrapping nutrients and act as a longtime nutrient carrier, while chemically modified and chelated CRFs are produced by changing lignin structure to produce more active site and interaction between lignin and nutrients. In this review, lignin is evaluated on the basis of the manufacturing of various types of CRFs. The processes of lignin-based coated, chemically modified and chelated CRFs as well as lignin hydrogel-based CRFs are systematically summarized. Moreover, the general mechanism for controlled release of lignin-based CRFs is discussed. Finally, three common evaluation criteria of lignin-based CRFs efficiency are proposed. Overall, the use of lignin-based CRFs has the potential to greatly enhance resource efficiency and environmental protection. [Display omitted] • Lignin-based CRFs have become particularly attractive in sustainable agriculture. • Coating, chemical reaction, and chelation for lignin-based CRFs are summarized. • General mechanism for controlled release of lignin-based CRFs is discussed. • Three common evaluation criteria of lignin-based CRFs efficiency are proposed. [ABSTRACT FROM AUTHOR]

The combined procedure of catheter ablation and left atrial appendage closure (LAAC) aims to simultaneously control the heart rhythm and reduce the risk of strokes in patients with atrial fibrillation (AF). The study aims to evaluate the procedural safety and long-term outcome of the combined procedure in a large patient cohort. Clinical data of AF patients who underwent the combined procedure was retrospectively analyzed. Procedural and imaging follow-up parameters were compared between the transesophageal echocardiography-guided standard process and fluoroscopy-guided modified process, and between the single-seal WATCHMAN and dual-seal LACBES devices. Long-term outcomes included all-cause mortality, thromboembolic events, major bleeding, and recurrence of atrial tachyarrhythmias. A total of 1114 patients were included. The rates of procedure-related major complications were comparable between the standard and modified processes (3.7% vs. 2.2%, p = 0.219), except for a higher incidence of respiratory depression in standard process group (0.9% vs 0%, p = 0.037), and between WATCHMAN and LACBES devices (2.4% vs. 3.3%, p = 0.535). The follow-up imaging evaluation revealed a high rate of satisfactory seals (99.7%) and a low rate of device related thrombus (1.9%), which were similar between two process groups and devices. The follow-up of over 1960 patient-years revealed low rates of mortality, thromboembolism, and nonprocedural major bleeding (1.8, 3.2, and 0.9 per 100 patient-years, respectively). Recurrent atrial tachyarrhythmias was observed in 23.9% patients. The results supported the safety and long-term efficacy of the combined procedure of catheter ablation and LAAC. Fluoroscopy-guided LAAC device implantation may be considered in experienced centers. • The safety of the combined procedure of catheter ablation and left atrial appendage closure was acceptable. • Despite a longer fluoroscopy time, the fluoroscopy-guided process had lower risks of respiratory depression and a shorter procedure time and required less workers than the transesophageal echocardiography-guided process. • Long-term event rates of the combined procedure were low, including mortality, thromboembolic events, and major bleeding events. [ABSTRACT FROM AUTHOR]

• Modified xylan with good amphiphilicity was obtained under mild reaction conditions by hydroxypropylsulfonation. • HSX exhibited a satisfactory dispersion efficiency of MWCNTs in water. • The aerogels were prepared by freeze-casting technology which reveals excellent mechanical performance. • The aerogel is utilized to construct a pressure sensor, which exhibit high sensitivity (S = 2.17 kPa−1) and impressive responsiveness. Currently, aerogels are promising for wearable pressure sensors due to their superior flexibility and high sensitivity. However, uniform dispersion of conductive solid filler is a critical step in the preparation process. Herein, xylan with good amphiphilicity was obtained by hydroxypropylsulfonation under mild reaction conditions, which is accepted as a dispersant for multi-walled carbon nanotubes (MWCNTs) in water. The hydroxypropylsulfonated xylan (HSX) exhibited a satisfactory dispersion efficiency reached to 97.8 %. After standing for 20 days, there are still 76 % of MWCNTs stabilized in the dispersion. Then, the ultralight, flexible and superstable anisotropic aerogels were prepared by freeze-casting technology. The obtained aerogel reveals excellent mechanical performance, with a great compressibility (undergoing a strain of 70 %) and elasticity (91.8 % height retention after 100 cycles at a strain of 20 %). As a proof of concept, the HSX/MWCNTs aerogel is utilized to construct a pressure sensor, which exhibit high sensitivity (S = 2.17 kPa−1) and impressive responsiveness to human motions. This work demonstrates a promising flexible electronic material for wearable electronics, electronic skin, and human motion monitoring. [ABSTRACT FROM AUTHOR]

• A method for tuning topological interface states in a 1D elastic wave system by the incident angle is proposed. • Multiple topological interface states of SH modes are obtained in a wide incident angle region. • For P-SV coupled modes, the topological interface states can exist in both partial-polarization and omni-polarization bandgaps when the band inversion process happening on the Brillouin zone boundary or center. • As the band crossing happens within the Brillouin zone, the topological properties of bulk bands will not change. Topological interface states are currently attracting fast-growing attention in classical wave systems. However, little work has been done on the topological interface states in one-dimensional (1D) elastic wave systems, especially in the case of oblique incidence. This paper theoretically demonstrates the realization of topological interface states of elastic waves in a 1D composite structure composed of two phononic crystals (PCs) with different topological characteristics, which can be regulated by the incident angle. For the out-of-plane SH mode, multiple topological interface states can coexist in different common bandgaps. For the in-plane complex P-SV coupled mode, topological interface states can exist in both "partial-polarization" and "omni-polarization" bandgaps. All these topological interface states exist in wide incident angle regions. The polarization and the mode conversion of the interface states have also been discussed. Our results provide an innovative method to excite and tune topologically protected interface states for elastic waves, which may have potential applications in obtaining strong local vibration for different polarized elastic wave modes. [Display omitted] [ABSTRACT FROM AUTHOR]

Supercritical water gasification (SCWG) is a promising clean technology for coal utilization due to high chemical reactivity and no tar emission. However, the wall-type heat exchange in the SCWG system demands a large heating surface area and an extreme high-temperature heat source. This paper puts forward an optimized design, namely direct mass transfer, in which the final product gas is partially recycled back into the gasification reactor to supplement the gasification agent and provide sensible heat energy. A whole system simulation was established to analyze the mass flow and exergy efficiency in the reference design and the optimized design. The process analysis shows that the optimized design has higher exergy efficiency (85.6%) than that (72.5%) of the reference design. In the optimized system, direct mass transfer significantly alters the mass flow and exergy flow, with less influent water (33.3%), less heat transfer rate (30.5%), and less oxygen consumption (51.5%). Furthermore, sensitivity analysis shows that increasing circulation ratio, feedstock concentration, and preheating temperature can reduce oxygen consumption and improve gas output and efficiency. The study indicates that direct mass transfer has the potential superiority to solve the challenge of heat integration and facilitate the application of the industrial-scale SCWG system. • Direct mass transfer for supercritical water gasification of coal was simulated. • The optimized cold gas and exergy efficiency increase by 15.5% and 13.1%. • The direct mass transfer design greatly reduces exergy loss in heat integreation. • Higher circulation ratio leads to more CH 4 , less heat flux and higher efficiency. • The direct mass transfer has superiority for disposing low-concentration feedstock. [ABSTRACT FROM AUTHOR]

A novel lignin-based hierarchical porous carbon (L-HPC) was prepared to remove Cr(VI) from water by using industrial alkali lignin through simple hydrothermal-induced assembly and alkali activation strategy. The adsorbent were characterized by SEM-EDS mapping, TEM, BET, XPS, FTIR, Raman spectroscopy and zeta potential. The characterization results indicated that L-HPC contained three-dimensional connected channels and many adsorbing N, O and other adsorption groups, which is very beneficial for Cr(VI) adsorption. The kinetics showed that the L-HPC adsorption of Cr(VI) was chemical adsorption and mainly controlled by intraparticle diffusion. The isotherm and thermodynamics indicated that L-HPC adsorption of Cr(VI) conforms to the Freundlich model, L-HPC is a kind of multimolecular layer adsorbent, and the adsorption capacity of Cr(VI) by L-HPC was 887.8 mg/g, which was significantly higher than values for other adsorbents. Ion competition simulation and actual water body tests showed that L-HPC exhibits high selectivity for Cr(VI) adsorption, adsorption cycle experiments show that L-HPC maintains over 83% performance after 12 cycles. Cost analysis shows that L-HPC is suitable for mass production. Therefore, L-HPC is a Cr(VI) adsorbent with high efficiency, high selectivity, and high reusability, which is broadly applicable and shows favorable prospects. • A novel lignin-based hierarchical porous carbon were prepared. • The maximum adsorption capacity of L-HPC for Cr(VI) was 887.8 mg/g. • The adsorption mechanism of Cr(VI) by L-HPC was investigated. • L-HPC has high selective adsorption ability for Cr(VI). • L-HPC maintains 83.78% adsorption capacity after 12 regeneration cycles. [ABSTRACT FROM AUTHOR]

Abstract: Caragana korshinskii hemicelluloses were isolated with 10% KOH at 25°C for 10h from the delignified materials. The alkali-extractable hemicelluloses were then successively sub-fractionated by graded precipitation at final ethanol concentrations of 10%, 20%, 30%, 45%, 60%, and 80%, respectively. Neutral sugars and molecular weight analyses of the six hemicellulosic subfractions revealed that the molecular weights and the distribution of branches along the xylan backbone are different among the hemicellulosic fractions obtained in various ethanol concentrations. The less branched hemicelluloses with large molecules were precipitated in lower ethanol percentages, while with the increasing ethanol concentrations, more branched hemicelluloses with low molecular weights were obtained. 1H and 13C NMR studies revealed that the hemicellulosic subfraction precipitated at an ethanol concentration of 45% had a backbone of d-xylose residues and were branched mainly through 4-O-methyl-α-d-glucopyranosyl units. [Copyright &y& Elsevier]

Laboratory experiments were conducted to investigate the evolution characteristics of a type-a ISW packet propagating over a gentle slope. The elevation type-a ISW packet was generated by the gravity collapse of stratified density fluid, and its transformation process over the gentle slope was measured by use of the multichannel conductivity-probe arrays. The energy transmission and loss of the ISW packets during its evolution over the gentle slope were further analyzed. The experimental results showed that the evolution and energy transmission of the type-a ISW packet over the gentle slope is closely related to the amplitude of the leading wave in the wave packet. The conversion of the wave packet type is caused by the variations in amplitudes of the leading and tailing waves in the type-a ISW packet due to the topography effect. The distance between the adjacent waves in a type-a ISW packet gradually increases with the increasing propagation distance on the slope, as well as its increase rate is also enlarged. The wave speeds of both the leading and tailing waves always decrease with the propagation distance. The energy loss of the whole ISW packet increases with both the incident wave amplitude and the propagation distance. • The evolution process of a type-a ISW packet over a gentle slope was experimentally measured. • The wave amplitude, wave speed, and spatial distance variation of the leading and tailing waves of the type-a ISW packet with increasing propagation distance were analyzed. • The energy transmission and loss during the evolution process of a type-a ISW packet over a gentle slope and their influence factors were also analyzed. [ABSTRACT FROM AUTHOR]

• We use the multiply resonator as a new kind of building blocks to build acoustic metasurfaces. • The used multiply resonator is composed of real solid materials. • The acoustic metasurfaces have good performance in a water background. • The thickness of the acoustic metasurface is about two orders of magnitude smaller than the acoustic wavelength in water. In this paper, we propose an ultra-thin acoustic metasurface constructed of multiply resonant units to manipulate reflected wavefront. As a counterpart to the Helmholtz resonator (with monopolar resonance) and membrane-type resonator (with dipolar resonance), the multiply resonator are used in metamaterials to induce strong quadrupolar resonance. Here we use the multiply resonator as a new kind of building blocks to make acoustic metasurfaces. The used multiply resonant unit is composed of solid materials, and the acoustic metasurface can work in a water background. We demonstrate that the proposed acoustic metasurface achieves good performance in anomalous reflection, focusing, and carpet cloaking. The thickness of the acoustic metasurface is about two orders of magnitude smaller than the acoustic wavelength in water. A design of unit group is further proposed to avoid the phase discretization becoming too fine in such a long-wavelength condition. [ABSTRACT FROM AUTHOR]

Seismic surface waves, composed of many complex waves and difficult to attenuate, can be controlled and obstructed by seismic metamaterials applied in civil engineering to protect sensitive buildings, such as nuclear power plants and ancient buildings. In this paper, a seismic metamaterial based on Matryoshka-like structure is designed. The dispersion curves and transmission are simulated by using finite element method. Comparative study on the dispersion curves of Matryoshka-like seismic metamaterial with different layers shows that the more layers the Matryoshka has, the more band gaps, the more resonant modes and the wider band gap are provided. Moreover, the vibration modes for Matryoshka-like seismic metamaterial are computed and analyzed to clarify the mechanism of widening band gaps. And the effectiveness of the Matryoshka-like seismic metamaterial in attenuating surface waves within the 0.1–13.1 Hz regime are demonstrated. Although we focus on geophysical structure, the proposed metamaterial provides possible alternative for various phenomena such as the vibration and noise attenuation because the center frequencies of band gaps can be easily achieved by modulating the material and geometrical parameters. [ABSTRACT FROM AUTHOR]

A new green hydrogel has been synthesized by crosslinking lignosulfonate (L), sodium alginate (SA) and konjaku flour (KJ). We have optimized the ratio of the three synthesized polymers using an orthogonal design of experiments and characterized this hydrogel using SEM, BET and FTIR spectra. We have added the hydrogel into soil and investigated its degradability in soil and its influence on chemical and physical properties of soil, such as maximum water holding capacity, saturated hydraulic conductivity, water retention curve and nutrient retention and evaluated its performance when applied in drought stress tests on tobacco plants. The results show that the maximum water absorption of optimized L/KJ/SA is 41.23 g/g. Adding the L/KJ/SA hydrogel to soil reduces saturated hydraulic conductivity, increases available water capacity of soil and reduces leaching of soil nutrient. The L/KJ/SA hydrogel can improve the photosynthetic capability of tobacco plants under drought stress and the levels of osmotic regulators such as proline and reducing sugar, and could prolong the growth time of tobacco plants up to 14 days, which significantly increases its mass harvest. The L/KJ/SA hydrogel also has good degradability, which can degrade 20% when buried in soil for 120 days. • A new green hydrogel is synthesized by crosslinking sodium lignosulfonate and sodium alginate. • The physical structure of the hydrogel is characterized by SEM, BET and FITR. • The hydrogel degrades by 20% after being buried in soil for 120 days. • The hydrogel increases soil available water content and reduces soil nutrient leaching loss. • The hydrogel extends tobacco growth time for 9-14 days under extreme drought conditions. [ABSTRACT FROM AUTHOR]