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While there have been multiple recent reports in the literature focusing on the effects of magnetic field on the phase transformation behaviors, the research conducted with an ultra-high magnetic field greater than 20 T is still preliminary. In the current study, the structure evolution of Co-B alloys are experimentally studied with undercooling. The effects of a 25 T magnetic field on the solidification behavior and the subsequent solid-state phase transformation behavior have been investigated. The 25 T magnetic field is confirmed to have little effect on the homogeneous nucleation, but have some influence on the heterogeneous nucleation of Co3B and Co23B6 phases by modifying the wetting angle θ. The decomposition of Co23B6 phase in the subsequent cooling process can be effectively suppressed by applying the 25 T magnetic field. The present work might be helpful for not only theoretically understanding the influence of ultra-high magnetic field on the phase transformation behaviors but a potential technology of field-manipulation of magnetic materials.

The rapid development of wearable, highly integrated, and flexible electronics has stimulated great demand for on-chip and miniaturized energy storage devices. By virtue of their high power density and long cycle life, micro-supercapacitors (MSCs), especially those with interdigital structures, have attracted considerable attention. In recent years, tremendous theoretical and experimental explorations have been carried out on the structures and electrode materials of MSCs, aiming to obtain better mechanical and electrochemical properties. The high-performance MSCs can be used in many fields, such as energy storage and medical assistant examination. Here, this review focuses on the recent progress of advanced MSCs in fabrication strategies, structural design, electrode materials design and function, and integrated applications, where typical examples are highlighted and analyzed. Furthermore, the current challenges and future development directions of advanced MSCs are also discussed.

We propose a generative model and an inference scheme for epidemic processes on dynamic, adaptive contact networks. Network evolution is formulated as a link-Markovian process, which is then coupled to an individual-level stochastic SIR model, in order to describe the interplay between epidemic dynamics on a network and network link changes. A Markov chain Monte Carlo framework is developed for likelihood-based inference from partial epidemic observations, with a novel data augmentation algorithm specifically designed to deal with missing individual recovery times under the dynamic network setting. Through a series of simulation experiments, we demonstrate the validity and flexibility of the model as well as the efficacy and efficiency of the data augmentation inference scheme. The model is also applied to a recent real-world dataset on influenza-like-illness transmission with high-resolution social contact tracking records.

Surface roughening of hollow glass microspheres (HGMs) is a necessary step determining their adhesion ability with the following electroless plated metallization coating. In this paper, a new KF roughening and alkali washing strategy was proposed to replace HF roughening as a surface pretreatment for the following electroless plating metallization. In order to remove the byproduct of K2SiF6 from the roughening reaction of KF with HGMs, NaOH washing and KOH washing were conducted, the former of which was found to dissolve K2SiF6 effectively. The effects of KF roughening temperature, alkali concentration and HGMs loading on the recovery ratio, phase composition, surface morphology and performance of HGMs were investigated, through which such a pretreating strategy was found to not only decrease the damage ratio of HGMs compared to that by HF roughening, but also render the metallized HGMs a competitive absorbing ability for the electromagnetic wave in X-band and Ku-band. Finally, the related surface treatment and electroless plating mechanism were discussed. This paper illustrates successfully a new pretreatment strategy for development of lightweight HGMs-supported functional materials.

Natural sisal fiber is an environment-friendly and efficient material for soil reinforcement. Many studies have reported that the shear strength of soil has been improved by the addition of fiber. However, the mechanical properties of sand can be more effectively improved by the incorporation of water-based polymer and sisal fiber. An extensive laboratory testing program was conducted to determine the effect of water-based polyurethane and sisal fiber reinforcement on sand. Laboratory tests included sieve analysis, X-ray diffraction, conventional triaxial compression, and scanning electron microscopy (SEM) tests. The effects of polymer content (PC), fiber content (FC), fiber length (FL), and sample dry density (ρ) are thoroughly investigated. The results indicate that the increases of PC, FC, and ρ all improve the mechanical properties of sand. For FL, this improvement in shear strength was maintained to FLs of up to 18 mm. Beyond 18 mm, the shear strength decreased with further increase in FL. The mixing of polymer and fiber changes the failure mode from shear faulting to ductile flow. This indicates that the ductility of sand is improved. From the SEM images we found that sisal fibers, binding with colloidal materials formed by polymer, fill the sand voids and join the sand particles. This demonstrates that mixing of fiber and polymer can enhance the bonding of sand particles.

Vegetation has good application in slope stabilization, but its beneficial effects on reinforcing topsoil are generally limited by the soil properties it was cultivated in. This study aims at evaluating the strength improvements of sand-root composite by treating with polyurethane polymer and hence investigating the mechanism of polymer-root-soil interactions. Vegetation roots were selected and mixed with dry sand and polymer solution to prepare remolded specimens. A series of experimental tests were then performed at different percentages of root content (0, 0.4, 0.8, 1.2, and 1.6 % by weight of dry sand) and polymer content (1, 2, and 4% by weight of dry sand) to evaluate the shear parameters and unconfined compressive strength (UCS). The combined mechanism was studied by scanning electron microscopy (SEM) images. The results showed that the strengthening effect has greater efficiency with higher polymer content. Through varying contents of vegetation root, it was found that low root content induced an undesirable weakening effect on the strength of the treated soil. However, this situation was somewhat improved with the increase in root content. The good flexibility of polymers not only promote the capacity of soil to energy absorption, but also impart good ductility to soil. The presence of polymers greatly strengthens soil stability due to its special network structure, by which the improved shear resistance at the root-soil interface provides sufficient anchorage effect for the tensile strength of roots to be fully mobilized. Overall, the synergistic effect of root reinforcement and polymer treatment has the potential for its use in soil stabilization.

A considerable number of engineering hazards are caused by loose internal structure of sands. Thus, many researchers have explored a variety of reinforcement methods. A new reinforcement technique was experimentally evaluated in this study. In particular, a hybrid method with a combination of fiber and polymer was studied. Three different types of fibers (sisal, polypropylene, and palm) in combination with varying concentrations of polymers were experimented to improve the internal structure and strength of sand samples reconstituted at different densities. Through a series of laboratory tests, the compressive and tensile strength variations of different combinations were obtained, and the interaction between fibers and polymer inside the sand was evaluated by scanning electron microscopy (SEM). The experimental results show that the tensile and compressive strength of the reinforced sand increases with the increase of the polymer concentration, sample density, and different fiber combinations. This provides some references for future practical engineering applications.

Ultrafiltration (UF) technology is considered an efficient water treatment method. In recent years, researchers have been committed to enhancing the treatment efficiency of UF and alleviating membrane fouling. An effective method is to achieve this is through the use of coagulation as a pre-treatment to UF; however, during a long term operation, membrane fouling can occur due to the residual organic matters and the generation of microorganisms. In this study, we combine coagulation and ozonation as a pre-treatment of UF and compare four types of pre-treatment: coagulation, ozonation, coagulation followed by ozonation (C–O) and ozonation followed by coagulation (O–C). Results showed that ozonation alone did not perform well. Both combinations of coagulation and ozonation enhanced the organic matter removal efficiency, although membrane fouling was lowest following the C–O pre-treatment as the microbial load was reduced. While a slight increase in the yield of disinfection by-products was observed with the addition of ozonation, the concentration remained below the Chinese standard for tap water quality (100 μg/L).

Na0.44MnO2 has drawn great attention as a promising cathode material for sodium-ion batteries (SIBs) owing to its unique tunnel-type structure that allows facile Na+ insertion/extraction. We here report the controllable preparation of Na0.44MnO2 nanowires (NMO NWs) through electrospinning and annealing processes and their SIB cathode application to boost the ionic diffusion dynamics and cyclic stability. The well-shaped NMO NWs with diameters of 50–200 nm effectively favour the easy access to electrolyte, facilitate the electrons/Na+ ions transportation, and retard the active materials fracture/pulverization upon prolonged cycling. Consequently, fascinating electrochemical performance in terms of high-rate capability (120.4 mAh g−1 at 0.1C; 31.7 mAh g−1 at 50C) and unprecedentedly long cycling life (89% capacity retention after 3300 cycles) is achieved. Furthermore, the underlying Na-ion storage mechanism and migration kinetics have been pioneeringly elucidated by a combination study of ex-situ structure/valence analyses and first-principles computations. The pseudocapacitive behaviour of NMO NWs electrode is also identified to benefit the high-rate performance. Finally, a pouch-type sodium-ion full battery assembled by the NMO NWs cathode and hard carbon nanofibers anode delivers an admirable energy density of 165.3 Wh kg−1 and an outstanding capacity retention of 88.57% over 200 cycles, showing great prospects.

The membrane fouling is a challenge for the application of ultrafiltration, one of which the cake layer is the main influencing factor. However, the pros and cons of cake layer generated in the coagulation-ultrafiltration (C-UF) process needs to be explored. This study was carried out to investigate that the effect of a cake layer on the membrane fouling behavior with three Al species coagulants for different effluents. The results indicated that the fouling mechanisms of cake layer under different effluents conditions were diverse due to the particle characteristics. The Al hydrolysis that accompanied by the interaction between Al species coagulants and the –OH/-COOH functional groups of humic acid were conducted, and the effluents of Ala presented lighter membrane fouling. Meanwhile, the components mainly trapped by the membrane were soluble microbial products, protein, polypeptides and amino acid-like materials during C-UF process, because of the decrease in the proportion of fluorescence response. For the less/compact cake layer (system 2), the average of the external and internal membrane resistances were about 25 × 1010 m−1 and 21 × 1010 m−1, respectively, which caused severe membrane fouling. It was concluded that the poriferous/loose cake layer could effectively alleviate membrane fouling by re-adsorbing some organic matters.

This study investigated the tolerance, defensive response and methanogenic pathways of anaerobic granular slugde and anaerobic suspended sludge (AGS and ASS) exposed to different LCM concentrations. AGS presented a higher tolerance to LCM stress, accompanied with 20.8 ± 2.6% enhancement in methane production at 1000 mg/L LCM, which was likely attributed to the less cell deaths and extracellular polymeric substances (EPSs) protection. In the acidification stage, acetate accumulation was stimulated and the activity of acetate kinase was promoted by LCM. In the methanogenesis stage, propionate and butyrate utilization for methane production were impaired after LCM addition. LCM also improved the activity of pyruvate-ferredoxin oxidoreductase and strengthened the process of hydrogenotrophic methanogenesis, likely by accelerating interspecies electron transfer mediated by hydrogen. ErmB and ermF were the dominate LCM resistance genes in AGS under LCM pressure conferring the resistance mechanism of ribosomal protection.

In this study, hydrogenotrophic methanogenic mixed cultures taken from 13 lab-scale ex-situ biogas upgrading systems under different temperature (20&ndash, 70 &deg, C), pH (6.0&ndash, 8.5), and CO (0&ndash, 10%, v/v) variables were systematically investigated. High-throughput 16S rRNA gene sequencing was used to identify the microbial consortia, and statistical analyses were conducted to reveal the microbial diversity, the core functional microbes, and their correlative relationships with tested variables. Overall, bacterial community was more complex than the archaea community in all mixed cultures. Hydrogenotrophic methanogens Methanothermobacter, Methanobacterium, and Methanomassiliicoccus, and putative syntrophic acetate-oxidizing bacterium Coprothermobacter and Caldanaerobacter were found to predominate, but the core functional microbes varied under different conditions. Multivariable sensitivity analysis indicated that temperature (p &lt, 0.01) was the crucial variable to determine the microbial consortium structures in hydrogenotrophic methanogenic mixed cultures. pH (0.01 &lt, p &lt, 0.05) significantly interfered with the relative abundance of dominant archaea. Although CO did not affect community (p &gt, 0.1), some potential CO-utilizing syntrophic metabolisms might be enhanced. Understanding of microbial consortia in the hydrogenotrophic methanogenic mixed cultures related to environmental variables was a great advance to reveal the microbial ecology in microbial biogas upgrading process.

Coke oven gas is considered as a potential hydrogen source for biogas bio-upgrading. In this study, the effects of CO on biomethanation performance and microbial community structure of hydrogenotrophic mixed cultures were investigated under thermophilic (55 °C) and extreme-thermophilic (70 °C) conditions. 5% (v/v) CO did not inhibit hydrogenotrophic methanogenesis during semi-continuous operation, and 83–97% CO conversion to CH4 was achieved. Methanothermobacter thermoautotrophicus was the dominant methanogen at both temperatures and was the main functional archaea associated with CO biomethanation. Specific methanogenic activity test results showed that long-term 5% CO acclimation shortened the lag phase from 5 h to 1 h at 55 °C and 15 h to 3 h at 70 °C. CO2 was the preferred carbon source over CO for hydrogenotrophic methanogens and CO consumption only started when CO2 was completely depleted. M. thermoautotrophicus dominated mixed cultures showed a great potential in simultaneous hydrogenotrophic methanogenesis and CO biomethanation.

In this study, hydrogenotrophic methanogenesis with respect to methanogenic activity and microbial structures under extreme-thermophilic conditions were examined, and compared with the conventional thermophilic condition. The hydrogenotrophic methanogens were successfully acclimated to the temperatures of 55, 65 and 70 °C. Although acclimation was slower at 65 and 70 °C, hydrogenotrophic methanogenesis remained fairly stable. High-throughput sequencing using 16S rRNA analysis showed that the higher temperatures resulted in single archaea community dominated by hydrogenotrophic Methanothermobacter. Moreover, the syntrophic bacteria changed from Coprothermobacter and Thermodesulfovibrio at 55 °C to Thermodesulfovibrio at 70 °C. Specific hydrogenotrophic methanogenic rate at 70 °C was 98.6 ± 4.2 Nml CH4/g VS/hr, which was over 4-folds higher than that 8at 55 °C. The lag phase under extreme-thermophilic conditions was longer than thermophilic condition, which was probably due to the archaeal structure with low diversity. Extreme-thermophilic condition resulted in a shift in methanogenesis pathway from acetoclastic methanogenesis to hydrogenotrophic methanogenesis with the enrichment of Methanothermobacter thermautotrophicus.

The effect of strong static magnetic field (SSMF) on the microstructure and phase transformation temperature of Co38Ni33Al29 ferromagnetic shape memory alloy during heat treatment has been studied. Results indicate that the microstructure and phase transformation temperature are significantly affected by the external SSMF. With the increasing magnetic field intensity, the volume fraction of γ phase decreased from 13.2 to 5.1%, the morphologies of γ phase evolved from rods to discrete stripes, and a clear alignment of γ phase was observed. In addition, the transformation temperatures are also elevated as the magnetic field intensity increases. The martensitic transformation temperature (MS) and the Curie point (TC) rose by 13 K and 10 K respectively when 4 T SSMF was applied. Moreover, the coercivity (HC) dramatically reduced to 11.7 Oe at 4 T magnetic field. Magnetic domains formed in β phase and they became ordered with the enhancing intensities of magnetic field.

This study investigated membrane fouling in a coagulation/ultrafiltration (C-UF) process by comparing the floc properties and humic acid (HA) removal efficiency of three hydrous Al(III) species (Ala, Alb, and Alc). The results indicated that the coagulation and membrane mechanisms were different for all three Al species because of the differences in floc properties. The HA removal efficiency increased with increasing Al dosage until an equilibrium was reached at the optimal dosage of 6 mg L−1. In addition, membrane fouling gradually decreased as the Al dosages increased. Regardless of coagulant type, the OH and COOH functional groups of HA reacted with the Al species. Both external and internal membrane fouling were strongly dependent on the porosity of the cake layer and on the size distribution of the floc particulates, respectively. The pore area of the cake layer formed by the Ala-coagulated effluent was large because of the strong charge neutralization. Moreover, Ala generated large and loose flocs with a porous cake layer that mitigated external fouling. However, the internal fouling with the Alc coagulant was significant because the concentration of residual aggregates in the membrane pores was high.

Troilite-orthopyroxene intergrowths are present as a common material in the brecciated diogenite Northwest Africa (NWA) 7183. In this study, we report on the petrographic, mineralogical, and rare earth element abundances of the troilite-orthopyroxene intergrowths to constrain their origin and assess their implications for the diverse petrogenesis of diogenites. Two groups of troilite-orthopyroxene intergrowths with various grain sizes and mineral chemistry have been observed in NWA 7183. One group of intergrowths contains fine-grained (

Hierarchical urchin-like Fe 3 O 4 porous particles with 3D graphene modification (U-Fe 3 O 4 @RGO) are synthesized via cationic surfactant induced self-assembly of γ-FeOOH particles and graphene oxide (GO) sheets, followed by a calcination treatment. Fe 3 O 4 porous particles are tightly encapsulated by 3D graphene frameworks, which greatly improves the overall electrical conductivity and structural stability of the hybrids. With the help of synergistic effects between U-Fe 3 O 4 and graphene frameworks, U-Fe 3 O 4 @RGO anode demonstrates high reversible capacity, excellent cycling stability (2292 mA h g −1 specific capacity after 500 cycles at 0.5 A g −1 ) and outstanding rate capability (439 mA h g −1 specific capacity at 10 A g −1 ).

The Pb electrode is the most efficient and selective catalyst in reducing CO2 into HCOOH; however, the reaction mechanism remains elusive. Herein, we have investigated the mechanism of CO2 electroreduction to HCOOH on the Pb(111) surface using density functional theory calculations. We find that the effects of solvation and cations lead to different active intermediates for CO2 electroreduction (HCOO in gas-phase condition, both HCOO and COOH in solvent condition, and COOH in cation solution). In particular, the size and hydrophilic/hydrophobic nature of the cations are found to significantly affect the reaction selectivity and efficiency of CO2 electroreduction at different overpotentials. These findings rationalize several experimental observations and contribute to a thorough understanding of CO2 electroreduction.

Swine manure wastewater was treated in an anaerobic membrane bioreactor (AnMBR) that combined a continuous stirred tank reactor (CSTR) and a hollow-fiber ultrafiltration membrane, and the feasibility of ammonia and phosphorus recovery in the permeate was investigated. The AnMBR system was operated steadily with a high mixed liquor suspended solids (MLSS) concentration of 32.32 ± 6.24 g/L for 120 days, achieving an average methane yield of 280 mL/gVSadded and total chemical oxygen demand removal efficiency of 96%. The methane yield of the AnMBR is 83% higher than that of the single CSTR. The membrane fouling mechanism was examined, and MLSS and the polysaccharide contents of the extracellular polymeric substances were found to be the direct causes of membrane fouling. The effects of the permeation/relaxation rate and physical, chemical cleaning on membrane fouling were assessed for membrane fouling control, and results showed that a decrease in the permeation/relaxation rate together with chemical cleaning effectively reduced membrane fouling. In addition, a crystallization process was used for ammonia and phosphorus recovery from the permeate, and pH 9 was the optimal condition for struvite formation. The study has an instructive significance to the industrial applications of AnMBRs in treating high strength wastewater with nutrient recovery.

This study systematically determined the optimal dosage ratio and the viscosity (η) of co-coagulants, polyaluminum chloride (PAC) and poly dimethyldiallylammonium chloride (PDMDAAC), on coagulation performance and membrane fouling in a hybrid coagulation-ultrafiltration (C-UF) process for natural organic matter (NOM) removal. Floc characteristics—including floc size, fractal dimension, strength and re-growth ability—were studied with respect to coagulant-dosing operations. Membrane fouling was evaluated in association with assessment of NOM removal performance by the hybrid process. The best coagulation performance was achieved when PAC and PDMDAAC were dosed with 1.0 mg/L and 0.1 mg/L, respectively. The addition of PDMDAAC could enhance the NOM removal efficiency, especially at low PAC dosages. Co-coagulants PAC/PDMDAAC (ηPDMDAAC = 2.18 dL/g) resulted in formation of the largest flocs with the smallest Df under all shear conditions, while the flocs formed by PAC/PDMDAAC (ηPDMDAAC = 1.86 dL/g) had higher recovery abilities. The results from ultrafiltration experiments indicated that coagulation using PAC/PDMDAAC with a viscosity range from 0.99 dL/g to 1.86 dL/g can significantly reduce membrane fouling, leading to increasing water fluxes from 0.1170 to 0.4906 in the ultrafiltration process.

The effects of the composite flocculant, polyaluminium chloride and poly dimethyldiallylammonium chloride (PACl-PDMDAAC) in comparison with PACl on coagulation efficiencies and membrane fouling in coagulation-ultrafiltration (C-UF) process were analysed, which was conducted in the conditions of different basicity (B) values and the presence of Mg2+. Results showed that PACl-PDMDAAC enhanced the ability of charge neutralization and absorption bridging, and improved the coagulation efficiency. When B value was 1.5, the flocculant hydrolyzed to form more Alb morphology and effectively removed HA molecules. The presence of Mg2+ could improve the coagulation performance through bridging ability. The results of the ultrafiltration test showed that the flux reduction for PACl was 70%, while the flux reduction for PACl-PDMDAAC was 60% in C-UF process. PACl-PDMDAAC could effectively reduce membrane fouling mainly by reducing strongly attached cake/gel layer. When B value was 1.5, the Alb content of the flocculant was higher and the ability of adsorption charge neutralization was strong, resulting in forming a stable cake layer. Therefore, the membrane fouling was the lightest. In addition, the presence of Mg2+ in raw water reduced the membrane fouling.

Autophagy is a strictly regulated pathway involving the degradation of cytoplasmic organelles and proteins. Most autophagy-related genes have been identified in plants based on sequence similarity to homologues in yeast and mammals. In addition, the molecular mechanisms underlying plant autophagy have been extensively studied in the last decade. Plant autophagy plays an important role in various stress responses, pathogen defense, and developmental processes such as seed germination, pollen maturation, and leaf senescence. However, the regulatory mechanisms of autophagy in plants remain poorly understood. Recent studies have identified several plant autophagy regulators, which modify autophagy activity at transcriptional, post-transcriptional, and post-translational levels. In this review, we summarize recent advances in understanding regarding regulatory network of plant autophagy and future directions in autophagy research.

Aggregation-induced emission (AIE) is currently receiving intense interest because of its important implications in photophysics. The structure-property relationship decipherment of AIE luminogens is of crucial importance for the fundamental understanding and application exploration. In this research, a series of novel luminogens based on phosphindole oxide (PIO), including a peculiar one with a folded conformation and apparent through-space conjugation, were synthesized and studied as models to elucidate the AIE mechanism. The significant impacts of steric, conjugation and electronic effects on the AIE property are presented based on the results of crystallography analysis, optical spectra measurements and theoretical computation. Non-doped yellow organic light-emitting diodes were fabricated with the new PIO-based luminogens, and they exhibited high brightness, good electroluminescence efficiencies and low efficiency roll-off.

BCB is emerging as an attractive bonding adhesive for wafer bonding in 3-D integration. Although the bonding strength of BCB is satisfactory with the assist of adhesion promoter, it is found that BCB suffers from interface delamination in harsh chemical or thermal conditions. This paper proposes, at chemical bond level, that the mechanism of interface delamination in KOH solution is attributed to the decomposition of Si O Si bonds at the interface between substrates and AP3000 adhesion promoter as a result of hydrolysis. Silicon dioxide and silicon nitride films with various densities of Si H and Si N bonds are prepared, and the bond densities are measured using infrared spectroscopy. The corresponding interface delamination rates of these films and BCB in KOH solution are measured, and the relations between the bond densities and the delamination rates are obtained for silicon dioxide and silicon nitride. It shows that the delamination rates decrease with the increase in the densities of Si O Si. These results demonstrate that the decomposition of Si O Si in KOH is the main reason for BCB delamination, and increase in the density of Si O Si improves the bonding strength.

Thiolate-protected gold nanoclusters, Aum (SR)n , have potential applications in many fields due to their high stability and remarkable electronic properties. However, the controlling factors in determining the stability and HOMO-LUMO gap of Aum (SR)n remain controversial, despite decades of work on the topic. Through DFT calculations, including nonlocal many-body dispersion (MBD) interactions, the geometric and electronic properties of Aum (SR)n clusters are investigated. Calculations demonstrate that the MBD interactions are essential for correctly describing the geometry and energy of the clusters. Greater anisotropic polarization and more atoms distributed in the shell of the clusters lead to more pronounced MBD interactions and higher stability of the clusters. Furthermore, the HOMO-LUMO gap of the clusters strongly depends on the gold core. These results provide critical clues for understanding and designing Aum (SR)n clusters.

Epichlorohydrin-dimethylamine (DAM-ECH) copolymer was acquired by polycondensation of hazardous reagents: epichlorohydrin (analytical reagent, A.R.) and dimethylamine (A.R.) with ethanediamine (A.R.) as cross-linker. Its coagulation and membrane performance as coagulation aid of polyferric chloride (PFC) was evaluated by comparing with other two cationic coagulation aids: poly dimethyl diallyl ammonium chloride (PDMDAAC) and polyacrylamide (PAM) in humic acid-kaolin (HA-Kaolin) simulated water treatment. Firstly, optimum dosages of PFC&DAM-ECH, PFC&PDMDAAC and PFC&PAM were identified according to their coagulation performance. Then their impacts (under optimum dosages) on membrane fouling of regenerated cellulose (RC) ultra-membrane disc in coagulation-ultrafiltration (C-UF) process were reviewed. Results revealed that small addition of DAM-ECH was the effective on turbidity and DOC removal polymer. Furthermore, in the following ultra-filtration process, external membrane fouling resistance was demonstrated to be the dominant portion of the total membrane fouling resistance under all circumstances. Meanwhile, the internal membrane fouling resistance was determined by residual of micro-particles(1) that cannot be intercepted by cake layer or ultrafiltration membrane.

Carbon-based hole-transporting material (HTM)-free CsPbBr3 perovskite solar cells (PSCs) provide new opportunities for promoting the commercial application of PSCs because of the low cost, simple preparation process and excellent stability under various extreme conditions. One of the remaining problems for inorganic CsPbBr3 PSCs is the low power conversion efficiency (PCE) due to the large energy level difference and inefficient hole extraction at CsPbBr3/carbon interface. Herein, polyaniline/graphite (PANi/G) composites are incorporated into carbon electrode to tailor work function and to improve hole-selectivity of back electrode for enhanced energy level alignment and interfacial hole extraction, leading to a remarkably reduced energy loss and charge recombination. The HTM-free CsPbBr3 PSC based on carbon-PANi/G electrode achieves a PCE of 8.87%, which is increased by 43.8% in comparison with 6.17% for the control device. Moreover, the unencapsulated device shows excellent long-term moisture tolerance with the initial PCE maintaining 93.5% even exposure to air atmosphere with 80% RH at 25 °C over 50 days. The successful improvement of energy level alignment and charge extraction in device by directly incorporating PANi/G composites into carbon electrode offers a promising strategy in developing low-cost and efficient HTM-free PSCs.

Hierarchical N-doped porous carbon has been prepared by assembling N-doped graphene quantum dots (N-GQDs) onto a carbonized metal-organic framework (cMOF-5) and used as an electrode material for supercapacitors. In this hierarchical composite structure, cMOF-5 provides an effective cubic porous framework with a large specific surface area and good electrical conductivity, while N-GQDs play an important role in enhancing the pseudocapacitive activity and improving the surface wettability of the electrode. Therefore, the N-GQD/cMOF-5 composite electrode material exhibits an outstanding specific capacitance of 780 F g-1 at 10 mV s-1 in a three-electrode system. Moreover, the composite electrode assembled in symmetric supercapacitors also displays a high specific capacitance of 294.1 F g-1 at 0.5 A g-1, excellent rate capacity and remarkable cycling stability with 94.1% of the initial capacitance retained after 5000 cycles at 5 A g-1. When used as the positive electrode, the N-GQD/cMOF-5//AC asymmetric supercapacitor exhibits an energy density of 14.4 W h kg-1 at a power density of 400.6 W kg-1, while the capacitance retention after 5000 cycles reaches 90.1%. The current N-GQD/cMOF-5 composite electrode paves a feasible avenue to improve the capacitive performances of supercapacitors by constructing heteroatom-doped, hierarchically porous carbon architectures.

Flexible supercapacitors have shown enormous potential for portable electronic devices. Herein, hierarchical 3D all-carbon electrode materials are prepared by assembling N-doped graphene quantum dots (N-GQDs) on carbonized MOF materials (cZIF-8) interweaved with carbon nanotubes (CNTs) for flexible all-solid-state supercapacitors. In this ternary electrode, cZIF-8 provides a large accessible surface area, CNTs act as the electrical conductive network, and N-GQDs serve as highly pseudocapactive materials. Due to the synergistic effect and hierarchical assembly of these components, N-GQD@cZIF-8/CNT electrodes exhibit a high specific capacitance of 540 F g-1 at 0.5 A g-1 in a 1 m H2 SO4 electrolyte and excellent cycle stability with 90.9% capacity retention over 8000 cycles. The assembled supercapacitor possesses an energy density of 18.75 Wh kg-1 with a power density of 108.7 W kg-1 . Meanwhile, three supercapacitors connected in series can power light-emitting diodes for 20 min. All-solid-state N-GQD@cZIF-8/CNT flexible supercapacitor exhibits an energy density of 14 Wh kg-1 with a power density of 89.3 W kg-1 , while the capacitance retention after 5000 cycles reaches 82%. This work provides an effective way to construct novel electrode materials with high energy storage density as well as good cycling performance and power density for high-performance energy storage devices via the rational design.

Strong static magnetic field (SSMF) is a unique way to regulate the microstructure and improve the properties of materials. FeCoNi(AlSi)0.2 alloy is a novel class of soft magnetic materials (SMMs) designed based on high-entropy alloy (HEA) concepts. In this study, a strong static magnetic field is introduced to tune the microstructure, mechanical, electrical and magnetic properties of FeCoNi(AlSi)0.2 high-entropy alloy. Results indicate that, with the increasing magnetic field intensity, the Vickers hardness and the saturation magnetization (Ms) increase firstly, and then decrease and reach the maximum at 5T, while the yield strength, the residual magnetization (Mr) and the coercivity (Hc) take the opposite trend. The resistivity values (ρ) are found to be enhanced by the increasing magnetic field intensity. The main reasons for the magnetic field on the above effects are interpreted by microstructure evolution (phase species and volume fraction), atomic-level structure and defects (vacancy and dislocation density).

In this study, a novel polysaccharide (PCPs) was obtained from bamboo shoots (Chimonobambusa quadrangularis) processing by-products through the ultrasonic-assisted extraction (UAE) and Sephadex G-100 size-exclusion chromatography purification. By using a Box-Behnken design (BBD) to optimize the parameters for extracting the crude PCPs with UAE, the maximum yield of crude PCPs (8.76%) was obtained under the optimal extraction conditions as follows: ratio of water to raw material 20.2mL/g, extraction temperature 49°C, ultrasonic power 240W, and extraction time 40min. Structurally, PCPs was identified as hetero-polysaccharides, which was composed of Man, Rha, GlcA, GalA, Glc, Gal, Xyl, and Ara in a molecular ratio of 1.00:2.05:2.28:2.36:15.76:49.06:16.70:39.86. The molecular weight distribution analysis showed that PCPs had three components with molecular weights of 136.1, 29.7 and 8.3kD, respectively. The glycosidic linkage analysis showed that PCPs contained 1→or 1→6 glycosidic linkages (35.1%), 1→2 or 1→4 glycosidic linkages (14.8%), and 1→3 glycosidic linkages (50.1%). conformations. The obtained results revealed that PCPs with a semi-crystalline structure exhibited important functional properties including the repose angle, swelling index (SC), water retention capacity (WRC), and oil retention capacity (ORC). The viscoelastic property of PCPs system exhibited a gel-like behavior with storage modulus G' always being higher than loss modulus G″. PCPs displayed excellent thermal stability as assessed by rheology and TGA/DSC. Furthermore, PCPs exhibited good chemical antioxidant activities in DPPH, ABTS and hydroxyl radical scavenging abilities, and metal chelating activity.

Astaxanthin is a carotenoid of significant commercial value due to its superior antioxidant potential and wide applications in the aquaculture, food, cosmetic and pharmaceutical industries. A higher ratio of astaxanthin to the total carotenoids is required for efficient astaxanthin production. β-Carotene ketolase and hydroxylase play important roles in astaxanthin production. We first compared the conversion efficiency to astaxanthin in several β-carotene ketolases from Brevundimonas sp. SD212, Sphingomonas sp. DC18, Paracoccus sp. PC1, P. sp. N81106 and Chlamydomonas reinhardtii with the recombinant Escherichia coli cells that synthesize zeaxanthin due to the presence of the Pantoea ananatis crtEBIYZ. The B. sp. SD212 crtW and P. ananatis crtZ genes are the best combination for astaxanthin production. After balancing the activities of β-carotene ketolase and hydroxylase, an E. coli ASTA-1 that carries neither a plasmid nor an antibiotic marker was constructed to produce astaxanthin as the predominant carotenoid (96.6%) with a specific content of 7.4 ± 0.3 mg/g DCW without an addition of inducer.

Effects of ozonation and powdered activated carbon on removal of dissolved organic matter (DOM) and disinfection by-product (DBP) in reservoir water were intensively investigated in this study. Both the formation of carbonaceous DBP (C-DBP) and nitrogenous DBP (N-DBP) as well as their speciation were analyzed. Results exhibited that the addition of powdered activated carbon (PAC) greatly improved the removal of aromatic protein. Trihalomethanes (THMs) and haloacetonitriles (HANs) were the dominant species in C-DBP and N-DBP. The integrated coagulation and PAC processes could remove more than 70% of THMs and 93% of HANs precursors, while only 10.5 and 45% of capture were achieved by the single coagulation. The added ozone lowered the yields of HANs but synchronously increased the more toxic bromine-containing THMs from 78.5 to 128.1 μg/L. Kinetics parameters for THM formation indicated that the precursor creating the THMs fast could be easily removed by both the coagulation and PAC adsorption.

We have demonstrated a high power and high efficiency thulium-doped silica fiber laser using a cascade tandem pumping method. A 1915nm Tm-doped fiber laser was used as a pump source for another Tm-doped fiber laser with the output power of 63W at 1980nm, corresponding to the slope efficiency of ~80%, which is the highest power to our best knowledge. And the 3dB bandwidth was 0.24nm. The 1915nm Tm-doped fiber laser was pumped by 793nm diode laser and the slope efficiency was 51%. The preform of double cladding Tm-doped fiber for the tandem pumped fiber laser was manufactured by MCVD with using the vapor-solution hybrid doping method. The fiber has a ~25μm diameter, 0.098 NA(numerical aperture) core and 400μm diameter, 0.46 NA inner cladding. In the tandem pumped fiber laser, the resonant cavity consist of a high reflection FBG at 1980nm, flat fiber end and the homemade Tm-doped silica fiber. The optimal active fiber length was presented and it is found that when the length of homemade Tm-doped silica fiber was 7m, the efficiency was the highest. The influence of Tm concentration and ratio of Tm ion and Al ion on the efficiency was also explored. And it is found that the thulium-doped silica fiber with lower Tm concentration and higher Tm:Al ratio had lower optical efficiency. Meanwhile, the optimal fiber length became shorter.

Adding acid control of the circulating water in thermal power plants is one of the important measures of water quality regulation. It is a very complex industry control process, which has the characteristics including nonlinear with description difficulty, pure lag(delay), large inertia, time-varying, etc. For the adding acid control system in thermal power plants, normal PID control can not achieve ideal control effect. On this basis, a new fuzzy PID control strategy based on expert system is put forward in this paper. The simulation experiment is carried out with MATLAB. The results demonstrate that in adding acid control system of circulating water with hysteretic and nonlinear characteristics, the expert fuzzy PID control proposed in this paper can greatly improve the dynamic performance of system which has strong adaptability and robustness, and better control effect is obtained as a result.

Two kinds of aluminum-based coagulants and epichlorohydrin-dimethylamine (DAM-ECH) were used in the treatment of humic acid-kaolin simulated water by coagulation-ultrafiltration (C-UF) hybrid process. Coagulation performance, floc characteristics, including floc size, compact degree, and strength were investigated in this study. Ultrafiltration experiments were conducted by a dead-end batch unit to implement the resistance analyses to explore the membrane fouling mechanisms. Results showed that DAM-ECH aid significantly increased the UV254 and DOC removal efficiencies and contributed to the formation of larger and stronger flocs with a looser structure. Aluminum chloride (Al) gave rise to better coagulation performance with DAM-ECH compared with poly aluminum chloride (PACl). The consequences of ultrafiltration experiments showed that DAM-ECH aid could reduce the membrane fouling mainly by decreasing the cake layer resistance. The flux reductions for PACl, Al/DAM-ECH (dosing both Al and DAM-ECH) and PACl/DAM-ECH (dosing both PACl and DAM-ECH) were 62%, 56% and 44%, respectively. Results of this study would be beneficial for the application of PACl/DAM-ECH and Al/DAM-ECH composite coagulants in water treatment processes.

Ultra-filtration technology has been increasingly used in drinking water treatment due to improvements in membrane performance and lowering of costs. However, membrane fouling is the main limitation in the application of ultra-filtration technology. In this study, we investigated the impact of four different pre-treatments: Coagulation, adsorption, coagulation followed by adsorption (C-A), and simultaneous coagulation and adsorption (C+A), on membrane fouling and natural organic matter removal efficiency. The results showed that adsorption process required a large amount of adsorbent and formed a dense cake layer on the membrane surface leading to severe membrane fouling. Compared to adsorption alone, the coagulation and C-A processes decreased the transmembrane pressure by 4.9 kPa. It was due to less accumulation of particles on the membrane surface. As for water quality, the C-A ultra-filtration process achieved the highest removal efficiencies of natural organic matter and disinfection by-product precursors. Therefore, the addition of adsorbent after coagulation is a potentially important approach for alleviating ultra-filtration membrane fouling and enhancing treatment performance.

The effect of thermal cycling treatments on the thermal stability and mechanical properties of a Ti48Zr20Nb12Cu5Be15 bulk metallic glass composite (BMGC) has been investigated. Results show that moderate thermal cycles in a temperature range of −196 °C (cryogenic temperature, CT) to 25 °C (room temperature, RT) or annealing time at CT has not induced obvious changes of thermal stability and then it decreases slightly over critical thermal parameters. In addition, the dendritic second phases with a bcc structure are homogeneously embedded in the amorphous matrix; no visible changes are detected, which shows structural stability. Excellent mechanical properties as high as 1599 MPa yield strength and 34% plastic strain are obtained, and the yield strength and elastic modulus also increase gradually. The effect on the stability is analyzed quantitatively by crystallization kinetics and plastic-flow models, and indicates that the reduction of structural relaxation enthalpy, which is related to the degradation of spatial heterogeneity, reduces thermal stability but does not imperatively deteriorate the plasticity.