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Permanent magnet coupling (PMC) generates a large amount of thermal energy due to the eddy current induced in the metal isolation cylinder, resulting in performance degradation. The magnetic-thermal-mechanical coupling analysis has an important impact on the design and operation of PMC devices. In this paper, the Maxwell equations are solved based on the separated variable method; the 3D eddy current loss and magnetic torque equations are proposed; and the electrical conductivity, the convective heat transfer coefficient, and the magnetic-thermal-mechanical properties of PMC are presented. The 3D analytical coupling model calculates the temperature field and presents an uneven distribution of temperature along the coolant flow direction, and it then obtains a more precise magnetic field and torque under various temperatures. Furthermore, the working conditions such as rotor speed, coolant flow rate, and applied load are taken into consideration in the 3D analytical model. The results show that the eddy current loss is proportional to the square of the speed. With an increase in the load, the eddy current decreases. However, with an increase in the coolant flow, more eddy current loss would be produced, but the generated heat would be taken away by the increased coolant flow, resulting in a decrease in the temperature. The 3D analytical coupling model results are in good agreement with the experimental data, which is helpful to the design and optimization of the PMC system. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A method for scalable preparing free-standing defective-rich TiO 2 sheets was proposed. • Two-dimensional tiny defect-rich Ti□ x O 2-x δ− nanoplates were prepared by a simple method. • Ti□ x O 2-x δ+ nanoplates were self-assembled into free-standing sheets with aid of linker in freeze-drying process. • Self-assembled sheets were crystallized in free-standing defect-rich anatase sheets in hydrogenation process. • Anatase sheets were dispersed in water and coated on flexible substrate to form a visible-light-driven photocatalytic film. Abstract In this research, two interesting phenomena were reported and analyzed: First, two-dimensional tiny titania nanoplates (4–5 nm lateral size, 0.4–0.5 nm thickness) with rich edge-defects were found to self-assemble into free-standing thin sheets with large lateral size in a freeze-drying process with the aid of linker; Second, when subjected to a moderate hydrogenation treatment, these self-assembled sheets could be crystallized into integral anatase sheets while the edge-defects of the building blocks were maintained on the surface or inside the body of the crystal and the flexible sheet-like shape were also maintained. Based on these observations, a method for scalable preparing free-standing defect-rich TiO 2 with a two-dimensional sheet-like morphology was proposed. The defects (oxygen vacancies) endowed the TiO 2 a grayish-black color and visible-light responsibility. By using the dispersion of these defect-rich anatase sheets, a film could be densely deposited on flexible substrates in a layered structure and showed an efficient performance in acetaldehyde decomposition under the irradiation of visible light. Since it has always been a technical challenge to prepare crystallized visible-light-driven TiO 2 films on plastic substrates with a low heat tolerance, this work may also provide a new approach to this problem. [ABSTRACT FROM AUTHOR]

Phthalate diesters, including di-(2-ethylhexyl) phthalate (DEHP) and diethyl phthalate (DEP), are chemicals to which humans are ubiquitously exposed. Humans are exposed simultaneously to multiple environmental chemicals, including DEHP and DEP. There is little information available about how each chemical may interact to each other if they were exposed at same time. The present study investigated effects of the combinational exposure of rats to DEP and DEHP on fetal Leydig cell development. The results showed that the gestational (GD12-20) exposure of DEP + DEHP resulted in synergistic and/or dose-additive effects on the development of fetal Leydig cell. The lowest observed adverse-effect levels (LOAEL) for fetal Leydig cell (aggregation and cell size), and StAR expressions were of 10 mg/kg and, lower than when these chemicals were exposed alone. Also, mathematical modeling the response curves supports the dose-addition model over integrated-addition model. Overall, these data demonstrate that individual phthalate with a similar mechanism of action can elicit cumulative, dose additive, and sometimes synergistic, effects on the development of male reproductive system when administered as a mixture. [ABSTRACT FROM AUTHOR]

A novel process of flue gas desulfurization by aqueous fulvic acid (FA) solution with acid-base buffering capacity was developed. Experiments were carried out to investigate the influence of operating parameters such as the FA concentration, pH, temperature, gas flow rate, fly ash, O 2 , SO 2 inlet concentration, CO 2 and NO 2 on SO 2 absorption efficiency and Duration Time of High Efficiency (DTHE, the time of the SO 2 absorption efficiency above 95%) in a lab-scale bubbling reactor. The results show high FA concentration has more absorption capacity for SO 2 , and the optimum concentration of FA solution is 0.08 g mL −1 , at which point the absorption efficiency is above 98%. The inlet SO 2 concentration has little influence on absorption efficiency, but DTHE reduces with increasing inlet SO 2 concentration. O 2 has a little effect on absorption efficiency. The SO 2 absorption efficiency is not affected by pH change in the range from 5.5 to 3.3, and maintained above 97.4%. Fly ash can improve SO 2 absorption efficiency and DTHE. NO 2 can accelerate the oxidation of bisulfite to sulfate and promote SO 2 absorption. CO 2 hardly influences on SO 2 absorption efficiency, but the SO 2 absorption capacity decreases with the increasing of CO 2 partial pressure. Furthermore, the thermal stability and regenerability of FA were also evaluated by TG-DTG and XRD, respectively. The results demonstrate that FA with stable performances is a promising regenerative absorbent for the removal of SO 2 . [ABSTRACT FROM AUTHOR]

Background: 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) interconverts active 11β-hydroxyl glucocorticoids and inactive 11keto forms. However, its directionality is determined by availability of NADP+/NADPH. In liver cells, 11β-HSD1 behaves as a primary reductase, while in Leydig cells it acts as a primary oxidase. However, the exact mechanism is not clear. The direction of 11β-HSD1 has been proposed to be regulated by hexose-6-phosphate dehydrogenase (H6PDH), which catalyzes glucose-6-phosphate (G6P) to generate NADPH that drives 11β-HSD1 towards reduction. Methodology: To examine the coupling between 11β-HSD1 and H6PDH, we added G6P to rat and human liver and testis or Leydig cell microsomes, and 11β-HSD1 activity was measured by radiometry. Results and Conclusions: G6P stimulated 11β-HSD1 reductase activity in rat (3 fold) or human liver (1.5 fold), but not at all in testis. S3483, a G6P transporter inhibitor, reversed the G6P-mediated increases of 11β-HSD1 reductase activity. We compared the extent to which 11β-HSD1 in rat Leydig and liver cells might be coupled to H6PDH. In order to clarify the location of H6PDH within the testis, we used the Leydig cell toxicant ethane dimethanesulfonate (EDS) to selectively deplete Leydig cells. The depletion of Leydig cells eliminated Hsd11b1 (encoding 11β-HSD1) expression but did not affect the expression of H6pd (encoding H6PDH) and Slc37a4 (encoding G6P transporter). H6pd mRNA level and H6PDH activity were barely detectable in purified rat Leydig cells. In conclusion, the availability of H6PDH determines the different direction of 11β-HSD1 in liver and Leydig cells. [ABSTRACT FROM AUTHOR]

Thermal interface materials (TIMs) play an important role in the electronic components area due to the continued miniaturization and lightweight. As a novel material with a thermal conductivity as high as ∼5000 W m −1 K −1 , graphene is regarded as a promising filler to improve the thermal performance of the TIMs. In this study, graphene prepared by varied approaches are employed as filler to modified epoxy resin. All the resulting TIMs not only show excellent thermal conductivity under room temperature (the maximum value reaches 4.9 W m −1 K −1 with 30 wt% loading, thermal conductivity enhancement factor is up to 1900%), but also demonstrate great stability at high temperature. Experimental and calculated results manifest a strong coupling of phonon modes between graphene and the matrix. The influences from graphene on thermal conductivity of composites are discussed. Larger size graphene sheets and surface functional groups would further reduce the Kapitza thermal resistance between the interfaces of graphene and epoxy resin. Moreover, the tested mechanical properties demonstrate that adding of graphene does not influence the outstanding mechanical performance of the matrix. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance The in vivo effects of traditional herbal medicines are generally mediated by multiple bioactive components. The main constituents of Lotus Plumule are alkaloids such as liensinine, isoliensinine and neferine. In this study, a simple, sensitive, and robust analytical method based on ultra-performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS) has been developed for the determination of the three alkaloids in rat plasma using carbamazepine as internal standard (IS). Materials and Methods After precipitation of the proteins with acetonitrile, chromatography was performed on an Acquity UPLC BEH C18 column (2.1 mm×50 mm, 1.7 μm particle size) using a gradient elution with 0.1% formic acid in water and acetonitrile. Mass spectrometry involved positive electrospray ionization and multiple reaction monitoring (MRM) of the transitions at m / z 611.7→206.2 for liensinine, 611.3→192.2 for isoliensinine, 625.2→206.1 for neferine and m / z 237.1→194.2 for IS. Results The method was linear over the concentration range 5–1000 ng/mL with a lower limit of quantifof 5 ng/mL for each alkaloid. Inter- and intra-day precision (RSD%) were all within 11.4% and the accuracy (RE%) were equal or lower than 10.4%. Recoveries were more than 75.3% and matrix effects were not significant. Stability studies showed that the three alkaloids were stable under a variety of storage conditions. Conclusion The method was successfully applied to a pharmacokinetic study involving intravenous administration of liensinine, isoliensinine and neferine to rats. [ABSTRACT FROM AUTHOR]

The poly(vinylidene fluoride) (PVDF)/barium strontium titanate (BST) composites were fabricated by solution casting method. The microstructure and dielectric properties of composites comprising polyvinylidene fluoride (PVDF) and barium strontium titanate (BST) particles have been investigated. It was found that the permittivity of the BST/PVDF composites increases from 16 to 40 while loss tangent decreases from 0.27 to 0.19 with BST fillers increasing from 10 vol% to 40 vol%. The tunability of PVDF + 40 vol% BST composites was 7.2% under the bias voltage of 1.0 kV/mm and the energy density was 0.36 J/cm 3 , making it suitable for embedded capacitor applications. The dielectric properties of PVDF were improved by increasing BST fillers and studying the mechanism of interface reaction. [ABSTRACT FROM AUTHOR]

Deoxidation of manganese oxides in supercritical N , N -dimethylformamide (SC-DMF) is revealed, contrasting to previous amounts of reports on supercritical water oxidation. Mn 3 O 4 and MnO can be produced by the reaction starting from layered manganese oxides (δ-MnO 2 ) in a uniform supercritical process. Time effect can give rise to the transition to Mn 3 O 4 under low temperature, but the prolonged time, under a temperature lower than 200 ̊C, cannot cause this transition. Phase diagram is obtained, including three regions of MnO 2 , Mn 3 O 4 and MnO as the main material phase. The completion of transition accompanies with an oxygen loss course. Comparison between supercritical oxidation of water and supercritical deoxidation of organic DMF demonstrates the unique mechanisms of supercritical processing. In terms of the surface contacting fluid, deoxidation kinetics has a reciprocal law of growing size for manganese oxides. The new deoxidation procedure using organic solvent is proposed for the processing of metal oxides. [ABSTRACT FROM AUTHOR]

A novel template- and organic-free synthesis of TiO 2 nanostructures with controlled phase and morphology was realized through batch supercritical hydrothermal treatment (400 °C) of titanate nanotubes (TNTs) with H 2 O 2 in NaOH aqueous solution. Well-defined 3D titanate hierarchical spheres (THSs), 2D multilayered titanate nanosheets (TNSs), and 1D monodisperse anatase nanorods (ANRs) exposing (0 1 0) facets were prepared in 15 min by slightly varying the NaOH solution pH. Specifically, the obtained Na/H-THSs (without/with HCl neutralization) exhibited highly porous structures with large specific surface area (109 m 2 g −1 and 196 m 2 g −1 , respectively). Temperature-dependent phase and morphology evolutions of products under subcritical condition (200 and 300 °C) were investigated. The formation of the TiO 2 nanostructures from TNTs was proposed mainly following a dissolution–nucleation-growth mechanism, suggesting that both supercritical temperature and NaOH solution pH were determinant factors governing the nucleation and growth process and thus the phase and morphology. [ABSTRACT FROM AUTHOR]

The yield of graphene sheets fromsupercritical N,N-dimethylformamide(DMF) exfoliation of naturalgraphite is not high. It was found that using natural graphite whichhad been slightly treated by nitric acid as a starting material forsupercritical DMF exfoliation could enhance the yield of graphenesheets and maintain high quality (with the least defects). The yieldof graphene sheets is 1.5 times greater than that from supercriticalDMF exfoliation of natural graphite. Raman result indicates that the ID/IGof graphenesheets is 0.19. The atomic force microscopy image shows that the thicknessof graphene sheets is 0.72 nm. Moreover, the possible mechanism ofsupercritical DMF exfoliation of nitric acid slightly treated naturalgraphite (NT-NG) is proposed. [ABSTRACT FROM AUTHOR]

Abstract: Trimanganese tetroxide (Mn3O4) nanosheets can evolve into various morphologies in supercritical N,N-dimethylformamide (SC-DMF), including particulate materials, triangle, rhombus, cube, and other regular polyhedrons. The obtained polyhedrons have sizes from hundred nanometers to several micrometers (1–3μm), along with a growing course. The phases are changed from Mn3O4 to MnO, as the processing time increases. The growth of manganese oxides in SC-DMF has a rate of 28.7–61.5nm·min−1. The phenomena of accelerated growth for manganese oxides in supercritical fluid are discovered. The growth kinetics of manganese oxides is performed by the classical Lifshitz–Slyozov–Wagner (LSW) model. A mass transfer (MT) model of growth kinetics applicable to supercritical fluid surrounding is proposed. Solubility and diffusion, as main factors, are included in the proposed model. The theoretical model and the fitting curve are in accordance with experimental results. The growth of manganese oxides in SC-DMF satisfies the first-order kinetics, obeying the exponential law. [Copyright &y& Elsevier]

Highlights: [•] Novel 2D monolayer titania quantum dots (MTQDs) were synthesized from protonic lepidocrocite titania nanotubes in supercritical water. [•] The thickness of MTQDs is only ∼0.4nm and lateral size is ∼2nm. [•] PL, UV–vis, Raman properties of MTQDs were different from TNTs and anatase TiO2. [•] Structure and growth mechanism of MTQDs were discussed. [•] MTQDs were considered to be the crystal seeds for the phase transition from TNTs to anatase TiO2. [ABSTRACT FROM AUTHOR]

Three-dimensional graphene networks (3DGNs) with a controllable number of layers (from monolayer to few layers) are fabricated by CVD on a Ni foam rod (NFR) template. The special morphology of the NFR and accompanying concentration gradients of CH4 gas provide the necessary conditions to deposit the 3DGNs with varied thicknesses on different areas of one substrate. The high conductivity, large Brunner-Emmett-Teller (BET) area, and three-dimensional network of the 3DGNs make it a potential material for use in the electrochemical field. Supercapacitors with the 3DGNs-based electrode show a high energy density ~34.2 Wh kg-1 at a current density of 100 mA g-1, and a specific capacitance of 246 F g-1 is obtained in a 30 wt.-% KOH aqueous electrolyte solution. Moreover, the resultant devices maintain high performances under high current density conditions, indicating the outstanding stability of the prepared 3DGNs. [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensional graphene networks (3DGNs) are prepared by chemical vapor deposition with the nickel foam rod as a template. Continuous structure of the 3DGN efficiently reduces inter-sheet junction contact resistance between the graphene sheets and makes the sample a great channel for carrier transport. The as-prepared 3DGN is added into the photoanode to boost the photovoltaic performance of dye sensitized solar cells (DSSCs). Even the amount of the 3DGN is as low as 0.2 wt%, the short-circuit current density and power conversion efficiency (η) are obviously improved, which is due to the enhanced dye absorption amount and prolonged electron lifetime. Compared to that of pure P25 photoanode based DSSC, the η increases 32.7% under AM-1.5G one sun light intensity when the 3DGN (1 wt%)–P25 photoanode is adopted (from 4.96% to 6.58%). After optimizing the thickness of the added 3DGN, the η further increases to 6.87%. Moreover, DSSCs with the 3DGN based counter electrode are also fabricated, and a slight degradation (in η) is obtained in comparing with that of employing a Pt counter electrode under identical conditions. [Copyright &y& Elsevier]

Abstract: Graphene modified semiconductor photocatalysts (GMSP) have attracted extensive attention due to their great photoactivities and promising prospect in environmental area. Although several GMSP samples have been prepared, the photocatalytic mechanism of these composites under visible-light illumination is still misty. Based on their energy band structures， electron transport model of graphene/titanate nanotubes (TNTs) photocatalyst under visible-light illumination is proposed in this study. Graphene and TNTs make a metal–semiconductor junction, and graphene can play as a sensitizer to endow the photocatalyst with an excellent visible-light response. Quantum tunneling is the major way to achieve the electron transport between graphene and TNTs, and the tunneling probability was calculated in the theory. Moreover, by using scanning tunneling microscope, electron paramagnetic resonance and photoluminescence spectra, the electron transport from graphene to TNTs under visible-light irradiation is confirmed unambiguously. [Copyright &y& Elsevier]

Abstract: Two kinds of graphene modified TiO2 composites are synthesized by hydrothermal method and layer-by-layer self-assembly technology. Graphene/titanate nanotubes (GTNTs) films have great light-harvesting efficiencies, and the amount of graphene does not obviously influence their optical performance. Alternating graphene/TiO2 (prepared by supercritical treatment, GSCT) multilayer films possess superior electron transport ability, and the number of bi-layers plays as a central role for their electrical property. The outstanding light scattering and carrier transport properties of these promising films promote the performance of dye-sensitized solar cells (DSSCs). The power conversion efficiencies (η) of the DSSCs reach 6.46% and 7.54% under AM-1.5G by using GSCT-P25 (10 μm) and P25-GTNTs (15 μm) photoanodes, and the increases are 33.8% and 20.6% compared with that of by using a P25 photoanode with same thickness. The η reaches 8.67% when a preliminarily optimized GSCT-P25-GTNTs (15 μm) photoanode is adopted, which is far better than employing a pure P25 photoanode (6.25%). [Copyright &y& Elsevier]

Abstract: Titania nanosheets with {001} facets were produced by the supercritical N,N-dimethylformamide (SC-DMF) fluid exfoliation of the layered bulk titanate material. X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) showed the starting titanate crystals with layered structure; SEM, atomic force microscopy (AFM) and transmission electron micrographs (TEM) demonstrated the obtained two-dimensional nanosheets with a thickness of 1.3nm around and lateral dimensions of several microns; ultraviolet–visible (UV–vis) spectroscopy characterized the optic properties of the nanosheets with uniformity and the disassembly of layered structure. Absorbance peak is centered at 301nm and the molar extinction coefficient is 1.01×102 mol−1 dm3 cm−1; thermogravimetric analysis (TGA) of the sediments revealed that the weight loss in the case of ice-cold water cooling was the least. The course of the SCF exfoliation was explained to be rapid intercalation and swollen exfoliation by thermal stress. Restacking of exfoliated nanosheets was shown by the in situ XRD technique, and ratios of the obtained single layers in the working conditions of furnace cooling, air cooling and ice-cold water cooling are increased up to 7.8%. [Copyright &y& Elsevier]

Abstract: By using layer-by-layer self-assembly technology, multilayered films consisting of alternated humic acid and Fe3+ ions ((HA/Fe3+)n, n=10,20,40) were fabricated on alumina fiber (AF) substrate for the first time. FTIR and FESEM results show that the (HA/Fe3+)n thin films were effectively immobilized on the AF surface. The average thickness of a single bi-layer HA/Fe3+ is not sensitive to the total layers. On the contrary, the concentration of Fe3+ ions significantly influences this mean thickness. A loose and amorphous structure with some irregular pores was detected from the as-prepared specimens, while relatively smooth surface and denser structure were observed after carbonized at 1000°C. The large BET surface areas and excellent absorbability of the as-prepared and carbonized samples were found. Moreover, at room temperature, a ferromagnetic property of these samples was revealed by magnetism testing. Due to the adjustable number of layers, the ferromagnetic property is controllable. Therefore, these produces possess potential application as the support material in catalytic and target drug delivery areas. [Copyright &y& Elsevier]

Abstract: The effect of co-doping ZnO, Al2O3 and MgO on the microstructures and dielectric properties of Ba0.6Sr0.4TiO3 ceramics prepared by the mixed-oxide route at 1400°C was investigated. And a comparison criterion for the BST-based tunable ceramics was proposed. The results show that a cubic perovskite phase Ba0.6Sr0.4TiO3 and a face-centered-cubic spinel phase Mg(Zn)Al2O4 were observed in BST/MgO/Al2O3/ZnO (BMAZ) composite ceramics. When Zn2+ content exceeds solid solubility limit in the BST, excess ZnO will react with Al2O3 to produce ZnAl2O4 phase. With the increase of ZnO, the paraelectric–ferroelectric phase transition points of BMAZ ceramics shift to the lower temperatures, and the maximum of dielectric constant increased first and then decreased. A higher tunability which amounts to 27.4% under 1.0kV/mm biasing was obtained for BMAZ ceramics doped with 1.0wt% ZnO. [Copyright &y& Elsevier]

Abstract: Few-layer graphene (FG) is produced in supercritical N,N-dimethylformamide (DMF) using expandable graphite (EG) as starting material in less than 15min. Monolayer graphene is produced by exfoliation of FG in supercritical DMF. The samples were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), and Raman spectroscopy. AFM result reveals that the average thickness of FG is about 3nm and monolayer graphene is about 1.2nm. Raman result indicates that the I D/I G of FG is 0.3, which proves a small proportion of defects in it. Moreover, we have studied the effect of process parameters on the yield of FG. Results show that a yield of 7wt% can be obtained at an optimum condition (with concentration being 2mg/ml, temperature being 673K, and volume ratio being 0.67). Besides, the temperature of FG formation is very low (473K). Finally, these results show that EG is an excellent precursor for the fabrication of FG and monolayer graphene. [Copyright &y& Elsevier]

Abstract: (1− x)Ba0.6Sr0.4TiO3–xMgAl2O4(x =25, 30, 35 and 40wt%) composite ceramics were prepared by conventional solid-state reaction method. The microstructures, dielectric properties and tunability of the composites have been investigated. The XRD patterns analysis reveals two crystalline phases, a cubic perovskite structure Ba0.6Sr0.4TiO3 (BST) and a spinel structure MgAl2O4 (MA). SEM observations show that the BST grains slightly dwindle and agglomerate with increasing amounts of MA. A dielectric peak with very strong frequency dispersion is observed at higher MA content, and the Curie temperature shifts to a higher temperature with increasing MA content. The ceramic sample with 30wt% MA has the optimized properties: the dielectric constant is 1503, the dielectric loss is 0.003 at 10kHz and 25°C, the tunability is 23.63% under a dc electric field of 1.0kV/mm, which is suitable for ferroelectric phase shifter. [Copyright &y& Elsevier]

The recent progress using Raman spectroscopy and imaging of graphene is reviewed. The intensity of the G band increases with increased graphene layers, and the shape of 2D band evolves into four peaks of bilayer graphene from a single peak of monolayer graphene. The G band will blue shift and become narrow with both electron and hole doping, whereas the 2D band will blue shift with hole doping and red shift with electron doping. Frequencies of the G and 2D band will downshift with increasing temperature. Under compressed strain, the upshift of the G and 2D bands can be found. Moreover, the strong Raman signal of monolayer graphene is explained by interference enhancement effect. As for epitaxial graphene, Raman spectroscopy can be used to identify the superior and inferior carrier mobility. The edge chirality of graphene can be determined by using polarized Raman spectroscopy. All results mentioned here are closely relevant to the basic theory of graphene and application in nanodevices. [ABSTRACT FROM AUTHOR]

Abstract: An experimental apparatus was set up to simulate co-deposition of A1 and Fe on copper by pack cementation. The thermal history in the coating processes has been measured by K-type thermocouples. The effect of the pack mixture, holding temperature and heating rate on the temperature change on a copper surface were examined. The experimental results showed that a high A1 and Fe mass fraction in pack mixture causes an obvious temperature fluctuation while the NH4C1 mass fraction and the A12O3 mass fraction only slightly affect the temperature change. Two distinct jumps in the temperature of the sample occurred for all the experimental runs, which are strongly affected by the holding temperature. The heating rate of the pack mixture has a significant effect on the temperature change of the substrate surface. High heating rates cause an unsteady temperature change on the substrate surface. [Copyright &y& Elsevier]

Abstract: In this paper, large-scale porous NiTi shape memory alloy (SMA) sintered by self-propagating high-temperature synthesis (SHS) has been investigated numerically. The SHS reaction process could be divided into three steps: preheating, ignition and sintering. The mathematical model about ignition and sintering were constructed to investigate the effect of the preheating temperature and the initial degree of conversion on the combustion. The results showed that the SHS reaction could not be completed for large initial degree of conversion. The critical preheating temperature for completed combustion was also obtained for different initial degree of conversion. It needed at least 573K to complete the combustion for the initial degree of conversion 0.215, and 873K for the initial degree of conversion 0.56. The mean wave velocity increased with the increase of preheating temperature and decreased with the increase of the initial degree of conversion. [Copyright &y& Elsevier]

In this paper, the experimental and numerical study has been carried out to investigate the water jet impingement on a convex hemispherical surface. The pressure and skin friction coefficient distributions on the impingement surface were analyzed numerically. A great deal of attention was paid to analyze the effects of the jet impingement exit velocity and the nozzle-to-surface distance on the heat transfer characteristics. A comparison of the heat transfer coefficient was performed between the jet impingement on the convex surface and the flat plate. The results show that the Nusselt number for the convex surface is higher than that for the flat surface. The local Nusselt number is decreased monotonically from its maximum value at the stagnation point for lower Reynolds numbers. A secondary maxima occurs for higher Reynolds numbers. The experiment and simulation were performed with the following parameters: the jet impingement Reynolds number of Re = 1947-19478, and the nozzle-to-surface distance of L/D = 2.5-25. [ABSTRACT FROM AUTHOR]

Solidification and remelting of aluminum though alumina preform under a centrifugal force field were modeled numerically. Transient solidification and remelting phenomena appear on the infiltration front in three distinct regions: the remelting region, the solid–liquid congruent melting region and the uninfiltrated region. The regional extent of solidified metal and its solid volume fraction increase with the moving of the infiltration front. The speeds of the infiltration and remelting fronts decrease with decreasing porosity and rotational frequency. [Copyright &y& Elsevier]

Abstract: Enhancement of the electrical properties in an AlGaN/GaN high electron mobility transistor (HEMT) structures was demonstrated by employing the combination of a high mobility GaN channel layer and an AlN interlayer. The structures were grown on 50mm semi-insulating (SI) 6H-SiC substrates by metalorganic chemical vapor deposition (MOCVD). The room temperature (RT) two-dimensional electron gas (2DEG) mobility was as high as 2215cm2/Vs, with a 2DEG concentration of 1.044×1013 cm−2. The 50mm HEMT wafer exhibited a low average sheet resistance of 251.0Ω/square, with a resistance uniformity of 2.02%. The 0.35μm gate length HEMT devices based on this material structure, exhibited a maximum drain current density of 1300mA/mm, a maximum extrinsic transconductance of 314mS/mm, a current gain cut-off frequency of 28GHz and a maximum oscillation frequency of 60GHz. The maximum output power density of 4.10W/mm was achieved at 8GHz, with a power gain of 6.13dB and a power added efficiency (PAE) of 33.6%. [Copyright &y& Elsevier]

Abstract: Speciation of bio-available chromium in soils was performed using extraction with 0.05M EDTA followed by strong anionic solid-phase extraction. The step gradient elution technique with 0.1 and 0.5M NaCl as eluent in sequence was sufficient to separate Cr(III) and Cr(VI) with recoveries of 99.7 and 93.4%, respectively. During the determination of separated chromium species by graphite furnace atomic absorption spectrometry (GFAAS), 10% ammonium nitrate solution was co-injected with the sample to eliminate the interferences from the eluent matrix containing high concentrations of chloride. Linear calibration curves over the range of 0–15ngmL-1 were obtained with good correlation coefficients (R2=0.9976 for Cr(III)EDTA-, and 0.9897 for Cr(VI)). The sum of the chromium species determined after separation was in good agreement with total chromium from EDTA extraction of NIST soil standard SRM2709 (0.688μgg-1 Cr(III), 0.127μgg-1 Cr(VI), 0.742μgg-1 total Cr) and a local soil sample (0.030μgg-1 Cr(III), 0μgg-1 Cr(VI), 0.053μgg-1 total Cr). [Copyright &y& Elsevier]

A vertical mill platform for inner circulation is constructed to improve the grinding efficiency. A transparent plexiglass grinding chamber is utilized to study the influence of solids density, particle size, solid volume fraction and agitator speed on the variation and transition of flow pattern regimes. The change regulations of rotor speed to just circulation and complete circulation as well as system energy consumption are analyzed, the empirical correlations for predicting the rotor speed to just circulation and complete circulation are proposed based on the experimental data of particles-liquid mixtures. The results indicate that the flow of particles-liquid mixture shows four different flow patterns with the increase of the agitator speed. In addition, the process of transition between flow patterns is different when the volume fraction of particles is lower or higher than 20%. The just circulation speed and the complete circulation speed of particles increase as the volume fraction of particles increases. The total system power consumption increases slowly when the volume fraction of particles is lower than 40%; but it increases sharply if the solid volume fraction exceeds 40%. [Display omitted] • A vertical mill platform with an annular agitator is constructed to explore the flow pattern regimes of solid particles. • The distribution of flow pattern regimes are different when the solid volume fraction is lower or higher than 20%. • The effects of solids density, size and volume fraction on the just and complete circulation speed are quantified. • Empirical correlations for predicting the just and complete circulation speed of solid particles are proposed. [ABSTRACT FROM AUTHOR]

• Water-in-scCO 2 Pickering emulsion was prepared with aid of ultrasonication. • GO was used as stabilizer for water-in-scCO 2 Pickering emulsion. • Emulsions with high internal volume remained stable for over 10 h. • Effects of GO concentration and system pressure were investigated. • The superiority of GO as Pickering stabilizer was theoretically analyzed. With aid of ultrasonication, water-in-supercritical CO 2 (scCO 2) Pickering-type emulsions were successfully prepared by using graphene oxide as stabilizer. The phenomenon was observed from observation window that after the termination of ultrasonication, the darkness of the emulsion declined rapidly in a short period, and then kept relatively stable for a relatively long duration. The addition of graphene oxide (GO) greatly increases the proportion of dispersed phase (water) in the scCO 2 continuous phase. Under optimized conditions, GO emulsifies up to 23% water in scCO 2 with droplets around 0.5 μm–3 μm. The stabilization time of these emulsions exceeded 10 h and increased with system pressure and GO concentration. The superiority of GO as a Pickering stabilizer was theoretically analyzed in this study: by taking advantage of 2D morphology, GO sheets are more likely to irreversibly attach to the scCO 2 -water interface to form a stabilized emulsion than the conventional 3D particles. [ABSTRACT FROM AUTHOR]

Silicon oxycarbide (SiOC) is a promising anode material for lithium‐ion batteries, owing to the high capacity and superior structural stability. However, the application of SiOC anode is limited by its low conductivity and poor rate performance. Here, SiOC anodes were prepared by the pyrolysis of silicone resin (RSN‐217) at different temperatures (700, 850, 1000, and 1150° C), and the effect of graphitization degree and Si─O─C network on the electrochemical performance of SiOC anodes was investigated. The elemental and structural characteristics of the pyrolyzed SiOC ceramics at different temperatures were inspected using a broad spectrum of characterization techniques, and electrochemical performance testing methods, such as cyclic voltammetry and galvanostatic charge/discharge, were conducted on SiOC anode. SiOC‐1000 showed excellent electrochemical performance due to the highest graphitization degree of free carbon phase and the highest content of SiO2C2 and SiO3C units. Considerable research effort laid a foundation for exploring the lithium storage mechanism of SiOC anode. [ABSTRACT FROM AUTHOR]

Uniform dispersion of pristine graphene in polymers has always been a difficulty in the research and industry. In this paper, a simple but effective method was used to uniformly disperse the pristine graphene in NR matrix to prepare an NR/pristine graphene composite. The conductivity of this composite with 5 wt% graphene loading fraction was ∼0.005 S/m, around 4 orders of magnitude higher than that prepared by other methods with a similar loading fraction. The gauge factor (GF) of the strain sensor using the as-prepared composite as the component could be as high as 46, taking a lead positon in the reported strain sensors. Owing to the high sensibility, the sensor was suitable to be used for the detection of very subtle motions such as breathing or heartbeat. In a wrist-pulse testing, premature beats, less forceful heartbeats, and the "P""T""D″ waves of the heartbeats could be precisely monitored and distinguished. Swallowing and vocalization could also be efficiently detected by attaching the sensor on the subject's throat. Image 1 • Convenient method to uniformly disperse pristine graphene in natural rubber matrix was proposed. • Pressing treatment affected the conductivity and sensitivity of the composite. • The conductivity of composite with 5 wt% graphene loading fraction was around 0.005 S/m. • The GF of the strain sensor was as high as 46. [ABSTRACT FROM AUTHOR]

Layered titanates with large interlayer spacing (ca. 0.8–0.9 nm) facilitate Li + movement with less resistance, and are considered suitable anode materials for high power lithium ion batteries (LIBs). Herein, lepidocrocite-type titanate hierarchical spheres (W-THSs) assembled by nanowires are synthesized by supercritical hydrothermal treatment of sodium peroxotitanate complex solution and subsequent acid washing. Nanowire components in the W-THSs interpenetrate each other to form a mesoporous network with high specific surface area (183.6 m 2  g −1 ), which provides electrolyte penetration channels, enlarged electrode/electrolyte contact area, and short charge transport path, favoring fast Li + insertion/extraction. Consequently, W-THSs exhibits an excellent electrochemical performance, giving a high discharge capacity of 123.6 mAh g −1 even at 5.0 A g −1 , and still retaining 180.8 mAh g −1 after 500 cycles at 1.0 A g −1 . The rate capability of W-THSs is much superior to the compared anatase TiO 2 hierarchical spheres (AHSs) obtained by calcining W-THSs in the air. Moreover, cyclic voltammetry analyses reveal that a pseudocapacitive process occurs during the Li + storage in W-THSs, significantly contributing to the excellent rate capability. [ABSTRACT FROM AUTHOR]

Advanced flexible electrode is crucial in the development of flexible energy storage devices for emerging wearable and portable electronics. Herein, a free-standing flexible mesoporous Li 4 Ti 5 O 12 -rGO (LTO-rGO) nanocomposite film is rationally designed and fabricated for lithium ion batteries (LIBs). This efficient synthesis involves the growth of lithium titanate hydrate (LTH) precursors on the graphene oxide (GO) by a hydrothermal reaction, assembly into LTH-GO film by vacuum filtration with some extra GO added, and subsequent conversion into LTO-rGO nanocomposite film through calcination. When rGO content in the LTO-rGO film is set, the addition sequence of GO is found to affect its textural and mechanical properties. The resultant free-standing LTO-rGO electrode, taking advantages of high Li 4 Ti 5 O 12 loading of 73.9%, mesoporous layer-stacked channels with good electron/ion conductivity, good mechanical strength, and enlarged electrode/electrolyte contact area, delivers excellent electrochemical performance (e.g., specific capacity of 135.4 mAh g −1 at 40 C) over the electrode of conventional configuration. Moreover, no organic but all inorganic reagents are used in the synthesis, offering an eco-friendly, cost-efficient, and easily scalable way to fabricate binder-free flexible electrode for LIBs. [ABSTRACT FROM AUTHOR]

Excessive sintering shrinkage leads to severe deformation and cracking, affecting the microstructure and properties of porous ceramics. Therefore, reducing sintering shrinkage and achieving near‐net‐size forming is one of the effective ways to prepare high‐performance porous ceramics. Herein, low‐shrinkage porous mullite ceramics were prepared by foam‐gelcasting using kyanite as raw material and aluminum fluoride (AlF3) as additive, through volume expansion from phase transition and gas generated from the reaction. The effects of AlF3 content on the shrinkage, porosity, compressive strength, and thermal conductivity of mullite‐based porous ceramics were investigated. The results showed that with the increase of content, the sintering shrinkage decreased, the porosity increased, and mullite whiskers were produced. Porous mullite ceramics with 30 wt% AlF3 content exhibited a whisker structure with the lowest shrinkage of 3.5%, porosity of 85.2%, compressive strength of 3.06 ± 0.51 MPa, and thermal conductivity of 0.23 W/(m·K) at room temperature. The temperature difference between the front and back sides of the sample reached 710°C under high temperature fire resistance test. The low sintering shrinkage preparation process effectively reduces the subsequent processing cost, which is significant for the preparation of high‐performance porous ceramics. [ABSTRACT FROM AUTHOR]

Hepatic fibrosis is the common pathway for most chronic liver diseases, characterized by excessive accumulation of extracellular matrix (ECM) proteins. It has been shown that fibrotic ECM significantly hindered passage of nanoparticles. Efforts have been made by decorating degrading enzymes on surfaces of nanosized delivery vehicles to improve drug delivery. However, these strategies are restricted by limiting shelf-life. Inspired by the application of sonoporation in assisting drug delivery through blood-brain barrier and tumor tissues, we investigated whether sonoporation can be an alternative strategy in improving drug delivery for fibrotic diseases. Hydroxycamptothecin (HCPT), a potential drug in treating liver fibrosis, was selected as a model drug to evaluate the drug delivery efficiency and therapeutic effect among three delivery strategies, i.e., (1) injection solution, (2) delivery through liposomes, and (3) delivery via sonoporation. Our study showed that in addition to the improved drug delivery efficiency, the combination of HCPT and sonoporation led to synergistic effect and the mechanisms were investigated. The treatment group of HCPT delivered with sonoporation achieved the most significant attenuation in liver fibrosis among the three delivery strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Bi2O3-doped KSr2Nb5O15(KSNB) ceramics with relative density higher than 96% were successfully prepared by sintering at 1300°C. The addition of Bi2O3 will decrease the tetragonal degree of the materials, improve the densification, and promote the grain growth of KSNB ceramics. Relaxation behavior can be observed in KSNB ceramics, which is attributed to the complex response of the polar nanoregions and matrices resulting from substitution of Bi3+ for Sr2+ and K+. Bi2O3-doped KSr2Nb5O15 ceramics show good temperature-dependence performance and high dielectric tunability. KSNB ceramics with 4.0 wt% added Bi2O3 show the maximum tunability, and capacitance changes with temperature meet the requirement of the X7R standard, which makes these ceramics promising candidate materials for multilayer capacitors and tunable phase shifters. [ABSTRACT FROM AUTHOR]

Waterborne nanoemulsion of diglycidyl ether of bisphenol A type epoxy resin (DGEBA) with droplet size of around 124 nm was prepared by using an ultrasonic-assisted supercritical carbon dioxide (scCO 2 ) technique in an autoclave reactor at a low temperature (32 °C). A view cell positioned in-line with the ultrasonic probe allowed observation of the emulsification process. From the image analysis and droplet size measurement, the influence mechanisms of the ultrasonic power, the degree of mixing of scCO 2 with DGEBA, the adding amount of emulsifier, and the system pressure on emulsification process and emulsion droplet size were investigated. In the emulsification process, scCO 2 penetrated into the mixture and absorbed on the DGEBA molecular. The interactions between CO 2 and the functional groups of DGEBA reduced the chain-chain interactions of polymer segments and therefore efficiently reduced the viscosity of DGEBA at a low temperature. Meantime, the cavitation and acoustic streaming of ultrasound provided a shear force for the nanoemulsification and a disturbance force for the homogeneity of the emulsion. Therefore, the combination of scCO 2 and ultrasonication made it possible to prepare a long-term stable nanoemulsion under a low temperature. This ultrasonic-assisted scCO 2 emulsification method provides an efficient and solvent-free process for the preparation of waterborne nanoemulsions of, for example, some heat-sensitive and water-insoluble active substances at low temperature. [ABSTRACT FROM AUTHOR]

The pressure fluctuation characteristics of an annular spouted bed filled with coarse particles were studied by statistical and frequency analysis. The effects of spouting gas velocity, static bed height, and measuring point height on pressure fluctuation standard deviation and major frequency were systematically examined. The peak frequencies and the behavior of bubbles in the gas-solid spouted bed were observed. Experimental results show the unique features of the novel spouted bed filled with coarse particles: the pressure fluctuation standard deviation increases with the increasing of spouting gas velocity and static bed height; however, it decreases with the increasing of measuring point height. For U g < U ms , two distinct peaks with one around 0.5 Hz and the other around 5.5 Hz are shown; while for U g > U ms , three peaks with the highest one at around 4 Hz can be observed in the spectra, and the major frequency decreases apparently with the increasing of spouting gas velocity, and also decreases with the increasing of static bed height or measuring point height. The peaks in the power spectral density (PSD) of pressure fluctuation are in good agreement with the observed behavior of bubbles in the annular spouted bed. The results would be helpful for the identification of flow pattern in the annular spouted bed of coarse particles. [ABSTRACT FROM AUTHOR]

In this research, three kinds of graphene quantum dots (GQDs)—pristine graphene quantum dots (PGQDs), expanded graphene quantum dots (EGQDs) and graphene oxide quantum dots (GOQDs)—were produced from natural graphite, expanded graphite, and oxide graphite respectively in an ultrasound-assisted supercritical CO 2 (scCO 2 )/H 2 O system. The effects of aqueous solution content ratio, system pressure, and ultrasonic power on the yields of different kinds of GQDs were investigated. According to these experiment results, the combination of the intense knocking force generated from high-pressure acoustic cavitation in a scCO 2 /H 2 O system and the superior penetration ability of scCO 2 was considered to be the key to the successful exfoliation of such tiny pieces from bulk graphite. An interesting result was found that, contrary to common experience, the yield of PGQDs from natural graphite was much higher than that of GOQDs from graphite oxide. Based on the experimental analysis, the larger interlayer resistance of natural graphite, which hindered the insertion of scCO 2 molecules, and the hydrophobic property of natural graphite surface, which made the planar more susceptible to the attack of ultrasonic collapsing bubbles, were deduced to be the two main reasons for this result. The differences in characteristics among the three kinds of GQDs were also studied and compared in this research. In our opinion, this low-cost and time-saving method may provide an alternative green route for the production of various kinds of GQDs, especially PGQDs. [ABSTRACT FROM AUTHOR]

Electrochemical performance, abundance and cost are three crucial criteria to comprehensively evaluate the feasibility of Li 4 Ti 5 O 12 as an electrode material for lithium-ion batteries (LIBs). Herein, hierarchical hollow Li 4 Ti 5 O 12 microspheres (HLTOMs) assembled by zigzag-like nanosheets are synthesized by hydrothermal treatment of scalable lithium peroxotitanate complex solution using low-cost commercial H 2 TiO 3 particles as titanium sources, followed by a calcination treatment. Precursor solution concentration, Li/Ti ratio, hydrothermal temperature and duration are found correlative and should be optimized to obtain pure Li 4 Ti 5 O 12 products. A high yield of HLTOMs up to 120 g L −1 was achieved. Due to the unique morphology, the HLTOMs deliver an outstanding rate capability of 139, 125 and 108 mA h g −1 at 10, 20 and 30 C, respectively, and exhibit 94% capacity retention after 1000 cycles at 30C indicating excellent stability. These values are much superior to those of commercial Li 4 Ti 5 O 12 particles (CLTOPs), showing HLTOMs are promising anode materials for LIBs. [ABSTRACT FROM AUTHOR]

In this research, a pressure reactor coupled with an ultrasonic generator was built. The intense impact force generated from high-pressure acoustic cavitation in a supercritical CO 2 (scCO 2 )/H 2 O system and the superior penetration ability of scCO 2 were combined to enhance the exfoliation efficiency of natural graphite. The impacts of the aqueous solution content ratio, system pressure, ultrasonic power, and surfactant addition on graphite exfoliation efficiency were studied. Under optimal conditions, the graphene yield could reach more than 50% with 93% of the graphene sheets being less than three layers, and the suspension concentration could be greater than 2.5 g/L. In this approach, from raw material feeding to the discharge of products, natural graphite was directly exfoliated into high-quality graphene sheets in a few hours with a considerably high yield and concentration by using only CO 2 , H 2 O, and ethanol. This approach should be a feasible and promising method to produce high-quality graphene on a large scale and at a low cost. [ABSTRACT FROM AUTHOR]

Ceramic/polyetheretherketone (PEEK) composites show a wide range of applications and have attracted extensive interest in the scientific community due to their outstanding dielectric and mechanical characteristics. However, the interface connection between the ceramic and PEEK is a vital issue that must be addressed to improve their physical and electrical properties. In this work, the polyethersulfone resin (PES) was selected as interface modifier between barium strontium titanate (Ba 0.6 Sr 0.4 TiO 3 , BST) and PEEK. Cold-pressing sintering was used to create BST/PEEK materials with superior dielectric frequency stability and dielectric tunability. The effects of PES content on the morphology and dielectric characteristics of PES modified BST/PEEK materials were investigated. The results showed PES could improve the dispersion of BST particles in polymer. The dielectric constant, dielectric tunability, and breakdown strength increased first, then reduced as PES content increased. The composite had the most homogeneous microstructure and the best dielectric properties when the PES content was 7.5 vol%. The frequency dispersion factor F (x) was much smaller than that of other ceramic/polymer composites reported. In addition, the dielectric tunability of the composites could reach a relatively high level (34.18%) while the dielectric constant was as low as 14. The dielectric tunable efficiency (T uE) was proposed to evaluate the property of low dielectric constant and high dielectric tunability under DC bias. The T uE of PES modified BST/PEEK composites show the highest value comparing with reported dielectric tunable composites. This research laid the path for the development of a novel ceramic/polymer composite with good interface bonding and high dielectric tunability. The structure of a material plays a decisive role in its properties. We obtained PES-BST/PEEK composites with higher dielectric properties by improving the interfacial bonding of ceramic and polymer phases in the composites. The high dielectric tunability with low dielectric constant of the PES-BST/PEEK composites is beneficial to the engineering applications of composite materials in integrated circuits and microwave dielectric devices. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, barium ferrites (BFs) with an average particle size of 100 nanometers as filler are used to explore the improvement of the mechanical properties of casting polyurethane (CPU). The nano‐BFs‐filled CPU is prepared in situ by adding the suspension of nano‐BFs in DMF to polyurethane precursor. The dynamic mechanical analysis is carried out to investigate the viscoelastic properties of nano‐BFs‐filled polyurethane. It is found that the strain energy density (SED) and the hysteresis energy density (HED) of polyurethane composite increase significantly after adding nano‐BFs filler. For the filler content of 0.5 wt%, the SED and HED increase by 587% and 486% respectively, but the hysteresis loss for all of composites remains almost unchanged. The results of Payne effect study show that the storage modulus and the loss modulus of all nano‐BFs‐filled polyurethane composites are significantly higher than that of pure polymer. The storage modulus of 0.5 wt% nano‐BFs‐filled polyurethane is the highest. At 25°C, 1 Hz and strain of 10%, compared with pure polyurethane, the storage modulus of 0.5 wt% nano‐BFs‐filled polyurethane increases by 310%, while the loss modulus increases by only 116%. A small amount of nano‐BFs is sufficient to reduce the loss factor to 0.60 times that of pure polyurethane, which indicates that the material becomes more elastic after adding nano‐BFs. Our method can effectively coordinate the contradiction between strength and fatigue resistance of composites, significantly improving the energy storage modulus and reducing the loss factor while remaining the H index of hysteresis loss almost unchanged. [ABSTRACT FROM AUTHOR]

Depression is common among people with cardiovascular diseases. Therefore, the combined use of antidepressants and cardiovascular drugs is very common, which increases the possibility of drug interaction. Simultaneously compare the effects of duloxetine and fluoxetine on metoprolol metabolism, and provide evidence‐based guidance for medication safety. Sprague–Dawley rats were randomly divided into three groups: group A (10.3 mg/kg metoprolol alone), group B (10.3 mg/kg metoprolol + 6.2 mg/kg fluoxetine), and group C (10.3 mg/kg metoprolol + 6.2 mg/kg duloxetine). Tail vein blood was collected and subjected to the ultra‐performance liquid chromatography–tandem mass spectrometry (UPLC‐MS/MS) detection. Moreover, in vitro inhibition of fluoxetine and duloxetine were assessed by incubating liver microsomes and CYP2D6.1 with metoprolol. In in vivo study, the administration of fluoxetine or duloxetine significantly increased the AUC(0−푡) and AUC(0−∞) of metoprolol (P < 0.05). Differences between fluoxetine and duloxetine in plasma concentration were also investigated, and their pharmacokinetic parameters such as AUC(0−푡) and AUC(0−∞) were significantly distinct (P < 0.05). In vitro, fluoxetine and duloxetine inhibited the metabolism of metoprolol via mixed competitive mechanism of cytochrome P450. IC50 values of fluoxetine and duloxetine were 12.86 and 2.51 μM, respectively. Moreover, the metabolism rate of metoprolol was inhibited to 19.62% and 17.14% in recombinant human CYP2D6.1 by fluoxetine and duloxetine, respectively. Duloxetine showed a more significant inhibitory potential compared to fluoxetine in vitro, but the main pharmacokinetic parameters of fluoxetine and duloxetine revealed differences in inhibiting metoprolol metabolism in vivo. [ABSTRACT FROM AUTHOR]

By using monolayer titania quantum dots (MTQDs) colloid, a continuous and transparent ultrathin titania film was prepared simply by drop-cast or spray coating method at room temperature. The formation of this even and ultrathin film was not only because of the very thin thickness of two-dimensional MTQDs, but also because of the suppression of coffee-ring effect. The self-assembly behaviors of MTQDs were examined by AFM and the reason for the suppression of coffee-ring effect was discussed in detail. Furthermore, the photocatalytic performance of this MTQDs film was evaluated and an improvement was achieved by loading graphene. Comparison between MTQDs/graphene composite and sphere-shaped nanoTiO 2 /graphene composite indicated that, the face-to-face contact mode between MTQDs and graphene may contribute to the high activity of MTQDs/graphene composite. [ABSTRACT FROM AUTHOR]

A method to extend the operational bandwidth of metal-dielectric-metal (MDM) type absorptive metamaterials is proposed. An ultrathin, five-band absorptive metamaterial with wide-angle absorption and polarization sensitivity in the X-band is designed. The total absorption bandwidth across the five bands, with reflection losses below −10 dB (absorption rate greater than 90 %), is nearly 1 GHz. The physical mechanisms of absorption are analyzed through the distributions of surface current, electric field, and magnetic field. Samples were fabricated and tested, and the results were consistent with the simulation outcomes. To enhance the bandwidth of the absorptive metamaterial and its application prospects, magnetic materials such as barium ferrite and carbonyl iron were introduced into a rubber vulcanization layer, which was then combined with the ultrathin absorptive material to create a novel absorptive material. When the magnetic material content in the rubber layer was 50 wt%, the frequency range with reflection losses below −10 dB increased by approximately nine times, covering 69.5 % of the C-Ku band. This significantly broadens the bandwidth of the pure MDM-type absorptive metamaterial, providing a feasible solution for the design of broadband ultrathin absorptive materials. [ABSTRACT FROM AUTHOR]

Nanostructured silicon-based particles have been widely developed as a promising anode material for lithium-ion batteries. However, nanostructuring usually requires complicated procedures and huge environmental pollution, which seriously hinder the commercialization of silicon-based anodes. Here, a scalable micelle-assisted method is developed to generate nanostructured SiO X -based particles by preventing the condensation between the reactive silanol groups. Benefiting from the scalable nanostructuring procedure, the hydrophilic polyethylene oxide segment of F127 is anchored on the surface of graphene oxide (GO) by hydrogen bonding, and the micelle formed by F127 with the silane precursor can further prevent the aggregation of GO sheets during the reduction process, leading to the nanostructured SiO X /C particles are attached to the surface of reduced graphite oxide (rGO). The nanostructured SiO X /C and rGO composites can reduce the crack risk of SiO X during (de)lithiation processes and decrease the diffusion length for Li+, while the uniformly distributed graphene network limits the agglomeration of nanoparticles during cycling and helps to improve electronic conductivity. As a result, the synthesized SiO X -based anode shows excellent cycling stability (>90% capacity retention from the 3rd to 500th) and fast Li + transport performance. This strategy provides a new scalable method to generate nanostructured SiO X -based particles for high-performance batteries. [Display omitted] • Scalable micelle-assisted method for preparing nano-scale SiO X -based anodes. • SiO X -based particles can be uniformly anchored on the surface of graphene oxide. • The uniformly distributed graphene network limits nanoparticles agglomeration. • The designed SiO X -based anode shows high capacity, excellent cycling stability. [ABSTRACT FROM AUTHOR]

MgO–Al 2 O 3 –ZnO co-doped Ba 0.6 Sr 0.4 TiO 3 (BMAZ)/poly(vinylidene fluoride) (PVDF) composites were prepared via the solution casting method. The effects of the volume fraction of BMAZ on microstructure and dielectric properties of BMAZ/PVDF composites were investigated. In addition, logarithmic mixture rule and Yamada mixing laws were used for the theoretical prediction of these properties. The permittivity and loss tangent of the composites increased and decreased from 10 to 34 and 0.07 to 0.02, respectively, with increasing amount (i.e., from 10 vol% to 40 vol%) of BMAZ filler. Moreover, for shape factors of 1.5–3, the permittivity values predicted by using Yamada's model exhibited close correspondence to those determined experimentally. However, the dielectric tunability of the composites improved with increasing amount of BMAZ filler. In fact, a high dielectric constant tunability of 10.9% (under a bias of 1.0 kV/mm) were obtained for the composite with 40 vol% BMAZ; this value was higher than those of some Ba 0.6 Sr 0.4 TiO 3 -based ferroelectric ceramics, which rendered the composite with 40 vol% BMAZ suitable for tunable capacitor and phase shifter applications. [ABSTRACT FROM AUTHOR]