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Designing anisotropic thermally conductive networks in thermal management materials can effectively exploit the high in-plane thermal conductivity of two-dimensional fillers to achieve high heat transfer efficiency along the predetermined direction, which is the hotspot for thermal management materials. However, constructing such an interconnected network with an orderly alignment structure through thermally conductive fillers has proved challenging. In this study, a high-density cellulose-supported GnPs@PDA skeleton with an interconnected and ordered structure was successfully prepared through the stress-induced strategy. After embedding into the epoxy resin, the EP/CGP composites with 22.1 vol% filler content exhibit an excellent in-plane thermal conductivity of 8.39 W/mK under a 75 % compression ratio, which is 12.3 times higher than that without compression. The enhancement of thermal conductivity for EP/CGP composites under the stress-induced orientation strategy is illustrated by the finite element analysis and metal foam theory. Furthermore, the transient heat transmission processes of the composites are recorded to verify their prospect in thermal management applications. This novel approach sheds light on the fabrication of thermally conductive networks with interconnected and ordered structures for next-generation thermal management materials. [Display omitted] • Interconnected thermally conductive skeletons supported by cellulose networks. • Ordered and dense skeletons can be readily obtained by stress-induced strategy. • Surface modification of dopamine improves the assembly efficiency of the skeletons. • The obtained CGP skeletons greatly enhance the thermal conductivity of epoxy. [ABSTRACT FROM AUTHOR]

In ground-penetrating radar (GPR) or lunar-penetrating radar (LPR) interpretation, instantaneous attributes (e.g., instantaneous energy and instantaneous frequency) are often utilized for attribute analysis, and they can also be integrated into a new attribute, i.e., the instantaneous centroid frequency. Traditionally, the estimation of instantaneous attributes calls for complex trace analysis or energy operator schemes (e.g., the Teager–Kaiser energy operator, TKEO). In this work, we introduce the 1D higher-order differential energy operator (1D-HODEO) to track instantaneous attributes with better localization. In collocation with the mode decomposition algorithms, the 1D-HODEO performs along each A-scan on the decomposed mode slices to form the final profile of instantaneous centroid frequency by using the piece-wise correlation coefficients. Both a numerical model for simulating two-layer lunar regolith and the LPR Yutu-2 data show that the proposed instantaneous centroid frequency profile on the 1D-HODEO has better resolution, in comparison with that of TKEO and the traditional time-varying centroid frequency. In this work, we present a new approach for extracting instantaneous centroid frequency attributes which provides more comprehensive information in lunar stratigraphic interpretation and LPR attribute analysis. [ABSTRACT FROM AUTHOR]

• The carbon quantum dots by in-situ microwave carbonization is proposed to construct Poly(ethylene imine)-based dielectric nanocomposites. • In-situ synthesized carbon quantum dots have outstanding dispersion and hinder electron injection to improve breakdown strength. • The excellent efficiency and discharged energy density are achieved at elevated temperature. Advanced electronic equipment requires polymer film capacitors to work under harsh temperature and electric field conditions. However, the inevitable deterioration of the insulation performance with electric field and temperature will limit the improvement of high-temperature capacitive performance. Herein, we report a novel sandwich-structured dielectric nanocomposite, utilizing microwave radiation in-situ to synthesize subminiature carbon quantum dots (CQDs) in the middle layer. Comprehensive simulation and experimental results confirm that CQDs, as an electronic barrier, prevent carriers from passing through the interlayer, thereby significantly reducing the leakage current in the polymer matrix at high temperatures, and obtaining excellent breakdown strength. Thanks to the slightly increased dielectric constant and significantly reduced energy loss, the nanocomposites with the optimal loading exhibit an excellent discharged energy density of 4.10 J cm−3 with efficiency above 90 % at 200 °C, which is far superior to most current dielectric nanocomposites. We believe that this simple and economic strategy provides a new idea for the development of green dielectric capacitors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of BC/BF adsorbent for the first time through co-fermentation. • High PNP adsorption potential of BC/BF composite. • Pore filling, electrostatic interaction, and hydrogen bonding all involved in PNP adsorption. • Renewability and reusability of BC/BF adsorbent. Polyethylene terephthalate (PET) nano-plastics (PNP) is a major source of water pollution which in turn causes health issues in humans. There is no effective method to completely remove PNP from wastewater. In this study, bacterial cellulose (BC)/bacterial flocculant (BF) composite was produced from PNP ammonia hydrolysate through the co-cultivation of Taonella mepensis WT-6 and Diaphorobacter nitroreducens R9. The structural characterization of the BC/BF composite through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and thermal and mechanical analyses demonstrated that the amino-group-rich flocculant produced by the D. nitroreducens R9 was incorporated into the BC network without interfering the self-aggregation of cellulose fibrils. Fast PEP removal was observed in pure and tap water with maximum sorption capacity (Qmax) of 124.65 mg/g and 115.60 mg/g, respectively, whereas least removal was observed for campus lake water with a Qmax value of 84.78 mg/g. A 10 mM SO 4 2− significantly decreased the adsorption capacity to 44.52 mg/g, while 2 mM Ca2+ contributed to the adsorption of PNP with a maximum adsorption capacity of 144.78 mg/g at pH 6.0. The potential adsorption mechanism was investigated through adsorption kinetic studies, isothermal models, and thermodynamics studies. The adsorbed BC/BF was recycled by desorbing PNP with ammonia water, and the eluent could be utilized as a medium for sustainable production of BC/BF. The reusable BC/BF adsorbent produced through the co-culture technique can effectively control PNP pollution. [ABSTRACT FROM AUTHOR]

We describe a novel bioflocculant, MBF-15, which is an exopolysaccharide extracted from the alkaliphilic bacterium Paenibacillus jamilae. The biophysical characteristics of MBF-15 were determined using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. MBF-15 was also evaluated for its biocompatibility by examining its inflammatory, coagulant, and hemostatic properties in vitro and in vivo. Pretreatment of peripheral blood mononuclear cells with MBF-15 inhibited lipopolysaccharide-stimulated expression of inducible nitric oxide synthase, production of nitric oxide, and secretion of pro-inflammatory cytokines, including tumor necrosis factor-α and interleukin-6. In addition, MBF-15 increased both mRNA and protein levels of the anti-inflammatory cytokines transforming growth factor-β and IL-10. The hemocompatibility of MBF-15 was investigated by measuring the hemolysis ratio and clotting times. MBF-15 had high pro-thrombogenic activity but was not hemolytic. In a rat model, MBF-15 showed superior hemostatic properties compared with chitosan. Thus, MBF-15 offers a promising combination of anti-inflammatory and pro-coagulant properties that may be useful for hemostasis in a variety of clinical settings. [ABSTRACT FROM AUTHOR]

Bioflocculants are widely used in a large variety of applications, because of their wide range of flocculation. There is limited information in the literature about the ability of bioflocculants to perform beneficial functions without having adverse effects on blood components. In this study, general hemocompatibility of a bioflocculant (MBF-06) was investigated in an in vitro system, measuring flocculation of plasma proteins, red blood cell integrity, blood cell counts, platelet activation, clot formation, complement activation, cytotoxicity and inflammatory response. Effects of MBF-06 included low plasma protein flocculation, low platelet activation, low inflammatory response, no hemolysis or cytotoxicity and increased expression of coagulation markers, including prothrombin fragments 1 + 2. These findings suggested that the rapid hemostasis caused by MBF-06 resulted, essentially, from humoral coagulation. Overall, our observations revealed the great potential of MBF-06 as a novel hemostatic agent. [ABSTRACT FROM AUTHOR]

Field-grading polymer nanocomposites have drawn significant attention in high voltage electrical industries due to their excellent nonlinear conductive or dielectric properties. But composites with both nonlinear properties are rarely reported, and desirable nonlinear performance associated with excess fillers in the composite is at the expense of electric breakdown strength. In this work, BaTiO 3 nanoparticles were decorated successively using double-shell layers of TiO 2 and polydopamine, which are developed as novel nanofillers (BT@TiO 2 @PDA) for field-grading applications. Subsequently, BNNSs were prepared by liquid phase exfoliation, serving as the inhibitor of breakdown phase growth in the composites. Finally, novel epoxy nanocomposites (EP/BT@TiO 2 @PDA-OB) with BT@TiO 2 @PDA and oriented BNNSs were fabricated by a simple hot-pressing method. Results show that the hierarchically designed nanoparticles can make the composites possess not only nonlinear dielectric properties due to high ε r of BT and improved interfacial polarization, but also nonlinear conductive properties resulted from the organic semiconductor PDA shell. Nonlinear effective medium theory (EMT) was utilized to explain the nonlinear dielectric properties, and the hopping transport model considering Pool-Frenkel effect was applied to explain the nonlinear conductive properties. In addition, electric breakdown tests reveal that EP/BT@TiO 2 @PDA-OB has significantly enhanced breakdown strength (45.7 kV/mm) as compared to that of pristine epoxy resin (29.4 kV/mm) and EP/BT@TiO 2 @PDA-RB (randomly dispersed BNNSs, 36.2 kV/mm). It is expected that these results can open new avenues for the design of novel composites with both nonlinear conductive properties and dielectric properties as well as high breakdown strength. [Display omitted] [ABSTRACT FROM AUTHOR]

Karst groundwater is an important water resource but it is vulnerable to contaminants, due to the distinctive geological features of abundant transmissive fractures and conduits in the karst area which connect the surface to the underground systems. Anthropogenic activity-derived polycyclic aromatic hydrocarbons (PAHs) on the surface environment could enter groundwater easily and rapidly and threaten water security in karst areas. Samples in the multimedia environment from 10 specific karst spring systems from Western Hubei of Central China were collected to analyze 16 priority PAHs and to investigate their transport in these karst spring systems. The total concentrations of PAHs in the soil, river water, river sediments, spring water, and spring sediments ranged between 6.04 and 67.7 ng g−1, 4.56 and 11.4 ng L−1, 29.9 and 1041 ng g−1, 4.09 and 222 ng L−1, and 5.88 and 83.0 ng g−1, respectively. Levels of PAHs in this area were relatively low when compared to other karst areas. Proportions of low-molecular-weight (LMW)-PAHs in the water, sediments and soil (average 58.2–78.8%) were much higher than those of high-molecular-weight (HMW)-PAHs. The proportion of LMW-PAHs in the sediments (especially in river sediments) was higher than that in the soil. Characteristic ratio analysis and principal component analysis showed that PAHs were from high-temperature combustion of the mixture of coal and biomass, and vehicle emission, where coal and biomass combustion were the dominant sources. Significant correlations of PAH compositions in different media of karst spring systems were observed, especially in the Yuquangdong (YQD)-Migongquan (MGQ), Jiuzhenziquan (JZZQ), Xianyudong (XYD) and Fengdong (FD) karst spring systems, indicating the rapid PAH transport from the recharge area soil to the discharge area of spring water and sediments. [Display omitted] • Particle-promoted transport with rapid water flow was pivotal for PAH mobilization to sediments. • Different sources and matrix components lead to the differences in PAH concentrations and compositions in river sediments and spring sediments. • Coal combustion, biomass burning and vehicle emission account for 99.1% of sources of the total PAHs. • Significant correlations of PAH compositions were observed in the multimedia environment of karst spring systems. [ABSTRACT FROM AUTHOR]

Bioflocculants have been applied in numerous applications including heavy metals removal. A major bottleneck for commercial application of bioflocculant is its high production cost. Phenol-containing wastewater are abundantly available. However, the toxic phenol inhibited the microbial activities in the subsequent fermentation processes. Consequently, strains that can secrete phenol-degrading enzymes and simultaneously produce bioflocculants through directly degrading the phenol are of academic and practical interests. A phenol-degrading strain, Stenotrophomonas maltophilia ZZC-06, which can produce the bioflocculant MBF-06 using phenol-containing wastewater, was isolated in this study. The effects of culture conditions including initial pH, dissolved oxygen, phenol concentration, inoculum size, and temperature on MBF-06 production were analyzed. The experimental results showed that over 90% flocculating activity was achieved when the phenol was used as a carbon source and 4.99 g/L of MBF-06 was achieved under the optimized condition: 2.0% dissolved oxygen, 800 mg/L phenol concentration, 10% inoculum size, an initial pH of 6.0, and a temperature of 30 °C. The bioflocculant MBF-06 contained 71.2% polysaccharides and 27.9% proteins. The feasibility of cadmium removal using MBF-06 was evaluated. The highest flocculating efficiency for cadmium was 81.43%. This study shows for the first time that Stenotrophomonas maltophilia ZZC-06 can directly convert phenol into a bioflocculant, which can be used to effectively remove cadmium. [ABSTRACT FROM AUTHOR]

A novel bioflocculant (MBF-79) prepared using formaldehyde wastewater as carbon resource was investigated in the study. The optimal conditions for bioflocculant production were determined to be an inoculum size of 7.0%, initial pH of 6.0, and formaldehyde concentration of 350 mg/L. An MBF-79 of 8.97 g/L was achieved as the maximum yield. Three main elements, namely C, H, and O, were present in MBF-79 with relative weigh percentages of 39.17%, 6.74%, and 34.55%, respectively. The Gel permeation chromatography analysis indicated that the approximate molecular weight (MW) of MBF-79 was 230 kDa. MBF-79 primarily comprised polysaccharide (71.2%) and protein (27.9%). Additionally, conditions for the removal of arsenic by MBF-79 were found to be MBF-79 at 120 mg/L, an initial pH 7.0, and a contact time 60 min. Under the optimal conditions, the removal efficiencies of arsenate (0.5 mg/L) and arsenite (0.5 mg/L) were 98.9% and 84.6%, respectively. Overall, these findings indicate bioflocculation offers an effective alternative method of decreasing arsenic during water treatment. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia syndrome (SFTS) is caused by SFTS virus (SFTSV), a tick-borne phlebovirus in family Bunyaviridae. Studies have found that humans, domestic and wildlife animals can be infected by SFTSV. However, the viral ecology, circulation, and transmission remain largely unknown. Methodology/Principal Findings: Sixty seven human SFTS cases were reported and confirmed by virus isolation or immunofluorescence assay between 2011 and 2014. In 2013–2014 we collected 9,984 ticks from either vegetation or small wild mammals in the endemic area in Jiangsu, China, and detected SFTSV-RNA by real-time RT-PCR in both questing and feeding Haemaphysalis longicornis and H. flava. Viral RNA was identified in larvae of H. longicornis prior to a first blood meal, which has never been confirmed previously in nature. SFTSV-RNA and antibodies were also detected by RT-PCR and ELISA, respectively, in wild mammals including Erinaceus europaeus and Sorex araneus. A live SFTSV was isolated from Erinaceus europaeus captured during the off tick-feeding season and with a high SFTSV antibody titer. Furthermore, SFTSV antibodies were detected in the migratory birds Anser cygnoides and Streptopelia chinensis using ELISA. Conclusions/Significance: The detection of SFTSV-RNA in non-engorged larvae indicated that vertical transmission of SFTSV in H. longicornis might occur in nature, which suggests that H. longicornis is a putative reservoir host of SFTSV. Small wild mammals such as Erinaceus europaeus and Sorex araneus could be infected by SFTSV and may serve as natural amplifying hosts. Our data unveiled that wild birds could be infected with SFTSV or carry SFTSV-infected ticks and thus might contribute to the long-distance spread of SFTSV via migratory flyways. These findings provide novel insights for understanding SFTSV ecology, reservoir hosts, and transmission in nature and will help develop new measures in preventing its rapid spread both regionally and globally. [ABSTRACT FROM AUTHOR]

A novel bioflocculant (MBF83) prepared using methanol wastewater as nutrient resource was systematically investigated in the study. The optimal conditions for bioflocculant production were determined to be an inoculum size of 8.6%, initial pH of 7.5, and a methanol concentration of 100.8 mg L −1 . An MBF83 of 4.61 g L −1 was achieved as the maximum yield. MBF83 primarily comprised polysaccharide (74.1%) and protein (24.2%). The biopolymer, which was found to be safe in zebrafish in toxicity studies, was characterized using Fourier-transform infrared spectroscopy and elemental analysis. Additionally, conditions for the removal of arsenite by MBF83 were found to be MBF83 at 500 mg L −1 , an initial pH of 7.0, and a contact time of 90 min. Under the optimal conditions, the removal efficiency of arsenite was 86.1%. Overall, these findings indicate bioflocculation offers an effective alternative method of decreasing arsenite during wastewater treatment. [ABSTRACT FROM AUTHOR]

A novel strain (designated as ZCY-7) which could convert H-acid into bioflocculants was isolated from H-acid wastewater sludge. Conditions for bioflocculants production were optimized by response surface methodology (RSM) and determined to be inoculum size 9.65%, initial pH 7.0, and COD Cr of the H-acid wastewater 520 mg/L. The highest flocculating efficiency achieved for kaolin suspension was 95.1%, after 60 h cultivation. The yielded bioflocculant was mainly composed of polysaccharide (82.4%) and protein (14.2%), and maintained its flocculating activity in 0.4% (w/w) kaolin suspensions over pH 2–8 and 20–80 °C. Fourier transform infrared (FTIR) spectra showed that amino, amide and hydroxyl groups were present in the bioflocculant molecules. A viable alternative treatment technology of H-acid wastewater using this novel strain is suggested, which could largely reduce bioflocculants costs. In addition, flocculating mechanism investigation reveals that the bioflocculant could cause kaolin suspension instability by means of charge neutralization firstly and then promoted the aggregation of suspension particles by adsorption and bridge. It is evident from the results that H-acid wastewater could be used as a source to manufacture bioflocculants. [ABSTRACT FROM AUTHOR]

Polymeric materials doped with SiC particles can exhibit promising nonlinear properties that can be widely used in electrical field grading applications. However, excellent field-grading performance is at the expense of mechanical characteristics due to excess fillers in the composites. Therefore, how to realize synergistic optimization of electrical and mechanical performances in ultra-low SiC loading is urgent for practical applications. In this study, we report a novel strategy to achieve comprehensive enhancement of thermal, mechanical and electrical properties of epoxy composites with self-assembly surface-modified SiC particles on cellulose aerogel scaffolds. The composites exhibit excellent nonlinear electrical properties at a low SiC loading of 4.47 vol%, and introducing different volume fractions of SiC into cellulose aerogel supported epoxy composites can largely broaden the range of switching field. Meanwhile, the dynamic mechanical test reveals that the storage modulus and crosslinking density of the composites are markedly enhanced due to 3D interconnected structure, while the thermal conductivity of this composite is also notably improved by about 300%. This method provides a novel idea for electric field grading composites with concurrent reinforcement performances in potential applications. [Display omitted] [ABSTRACT FROM AUTHOR]

High cost is one of the limiting factors in the industrial production of bioflocculant. Simultaneous preparation of bioflocculant from the contaminants in wastewater was considered as a potential approach to reduce the production cost. In this study, caprolactam was verified as sole feedstock for the growth of strain Alcaligenes faecalis subsp. phenolicus ZY-16 in batch experiments. Chemical analysis showed that the as-prepared MBF-16 consisted of heteropolysaccharides (88.3%) and peptides (9.4%). XPS result indicated the plentiful acylamino, hydroxyl and amino groups in MBF-16, which have an indispensable role in amoxicillin flocculation. The flocculation of amoxicillin can be well stimulated by Freundlich isotherm equation, and the K f was up to 178.6524 for amoxicillin. The kinetic fitting results proved that the flocculation of amoxicillin by MBF-16 was chemisorbed. This contribution may develop a novel technology for the preparation of bacterial flocculants that can consume toxic substrates (caprolactam) and have potential applications in amoxicillin removal. • Caprolactam could be an available feedstock to produce bioflocculants. • Hydroxyl, amino and acylamino groups are abundant in the bioflocculant. • Cation-independent flocculant is produced by Alcaligenes faecalis. • Chemisorption is involved in amoxicillin and the bioflocculant. [ABSTRACT FROM AUTHOR]

Abstract: The quality of steel rolling is determined by numerous process parameters, which have to be selected before real production. This paper presents a simulation system that can provide a set of process parameters based on the available information and the quality requirement of products. Simulation parameters were calculated by using a differential element method. Based on a defined rolling model, the rolling thickness simulation of continuous cold rolling processes was conducted on a software platform within the MATRIX environment. The simulation was carried out as a combination of a discrete system and continuous system, so the system has high speed and is suitable for real time dynamic simulation. The simulation results matched the real process data very well. The model was proven to be suitable for the multivariable interactive problems of the continuous cold rolling process and could be used to guide production practice and new product development. [Copyright &y& Elsevier]

Dielectric polymers with high thermal conductivity are very promising in the fields of aerospace and electronic device packaging. However, composites with excellent dielectric properties usually have low thermal conductivity. It is usually to fill the polymer with thermal conductivity particles to improve the thermal conductivity, but the high content of filler often reduces the mechanical properties of the polymer. In this paper, the traditional insulating polymer epoxy resin was used as the matrix, by covering the surface of silicon carbide with graphene to form a core-shell structure and co-filled with nano diamonds to achieve the preparation of high-performance epoxy resin at low content. The results showed that at the filling content of 30 wt%, the thermal conductivity of epoxy nanocomposites showed a dramatic thermal conductivity enhancement of 1263%, the energy storage modulus increased by 1.1 GPa, and the dielectric loss remained unchanged at 50 Hz. The advantages of the composite are the structural design and surface modification of the filler, which not only take advantage of its inherent advantages, but also improve the interface area with the epoxy matrix. The composite materials with excellent properties are expected to provide theoretical guidance for the application of high thermal conductivity dielectric materials. • The core-shell structure was prepared for enhancing the thermal conductivity of epoxy nanocomposites. • Nano-diamond was used to suppress the increase of dielectric constant and dielectric loss. • The graphene shell layer can greatly improve the heat transfer efficiency. • Micro-nano structure was formed to improve the storage modulus. • SiC can prevent the formation of electrical conductive paths of graphene. [ABSTRACT FROM AUTHOR]

The major bottleneck for industrial applications of microbial flocculants is the high production cost. Here, a novel bacterium, Diaphorobacter nitroreducens R9, was isolated that can secret ligninase and cellulase and simultaneously produce bioflocculants (MBF-9) through conversion of ramie biomass. The production of MBF-9 was closely related to the ligninase and cellulase activities of D. nitroreducens. Both ligninase and cellulase showed peak activity at pH 8.5 and 6.0 and retained approximately 80% of cellulase activity and 95% of ligninase activity at pH 8.0. The optimal production conditions with the highest bioflocculant yield (3.86 g/L degumming wastewater) were determined at a fermentation time of 48 h, fermentation temperature of 30 °C, inoculum size of 4.0%, COD Cr of ramie degumming wastewater of 1500 mg/L and initial pH of 8.0. In addition, MBF-9 removed 96.2% turbidity, 79.5% chemical oxygen demand (COD), 59.2% lignin, and 63.1% sugar from the pulping wastewater at an MBF-9 dosage of 831.57 mg/L. • A novel bioflocculant-producing bacterium was isolated from ramie biodegumming wastewater. • The bacterium can secret ligninase and cellulase through conversion of ramie biomass. • The bioflocculants'production was closely related to the degradation of biomass. • The bioflocculant was applied for the treatment of real pulping wastewater. [ABSTRACT FROM AUTHOR]