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An innovative recyclable denitration strategy was proposed, where Fe-based oxygen carriers (OCs) with various oxidation states act as the agent reducing NO into N2. Herein, the detailed redox properties of OCs were exploited to reveal the possibility and characteristic of the recyclable iron reduction denitration processes. Fe2O3supported on Al2O3was first prepared, and the lattice oxygen migration ability of the prepared OCs was detected. Then, the OCs were reduced by CO to obtain the low-valence iron oxides/iron (FexOy/Fe) to reduce NO into N2under the presence and absence of reducing gas, various reduction degrees, and different temperatures. Results showed that the NO removal efficiency improves with a deeper reduction degree of the OCs and higher reaction temperature (800 °C). In addition, Fe2O3(104)/Al2O3with high Miller index prepared by the coprecipitation method exhibits higher NO removal efficiency than Fe2O3/Al2O3produced by the impregnation method since Fe2O3(104)/Al2O3shows larger specific surface area, more porous structures, and dangling bonds. Compared with the method of spraying iron powder in the furnace for denitration, recyclable iron reduction denitration is more economical and environmentally friendly.

A zwitterionic polymer–drug conjugate (ZPDC) strategy is developed for the co-delivery of paclitaxel (PTX) and gemcitabine (GEM) chemotherapeutics, as well as a near-infrared fluorescence imaging agent cyanine5.5 (Cy5.5). The well-defined ZPDC is synthesized by tandem azide–alkyne and thiol–ene click functionalization of a biodegradable acetylenyl/allyl-functionalized polylactide and zwitterionic character is conferred by sulfobetaine. It has a number-average molecular weight of 53.6 kDa, comprising 6.5% PTX and 17.7% GEM by weight. Cy5.5 moieties are readily introduced to the ZPDC viaconjugation. In aqueous solutions, the ZPDC exhibits a hydrodynamic diameter of 46 nm. In vitroMIA PaCa-2 human pancreatic cancer cells show strong ZPDC cellular uptake and cytotoxicity. In mice, the ZPDC exhibits long blood circulation, effective tumor accumulation, biocompatibility, therapeutic effect, and integrated imaging capacity. Overall, this work illustrates that ZPDCs are promising systems for chemotherapy delivery and bioimaging applications.

•A cooling structure combining upstream ramps and zigzag grooves is proposed.•The film coverage of the mist/air mixture can be significantly improved by the cooling structure.•The cooling structure can better utilize the vaporization latent heat of the droplet.•The cooling effectiveness is not linearly related to the ramp angle.•The structure can achieve ideal cooling effectiveness at the endwall under practical conditions.

Combinations of new antidepressants like duloxetine and second-generation antipsychotics like quetiapine are used in clinical treatment of major depressive disorder, as well as in forensic toxicology scenarios. The drug–drug interaction (DDI) between quetiapine and duloxetine is worthy of attention to avoid unnecessary adverse effects. However, no pharmacokinetic DDI studies of quetiapine and duloxetine have been reported. In the present study, a rapid and sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous determination of quetiapine and duloxetine in rat plasma. A one-step protein precipitation with acetonitrile was applied for sample preparation. The analytes were eluted on an Eclipse XDB-C18column using the mixture of acetonitrile and 2 mM ammonium formate containing 0.1% formic acid at a gradient elution within 6.0 min. Quantification was performed in multiple-reaction-monitoring mode with the ion transitions m/z 384.4 → 253.2 for quetiapine, m/z 298.1 → 154.1 for duloxetine and m/z 376.2 → 165.2 for IS (haloperidol), respectively. Good linearity was obtained in the range of 0.50–100 ng/mL for quetiapine (r2 = 0.9972) and 1.00–200 ng/mL for duloxetine (r2 = 0.9982) using 50 μL of rat plasma, respectively. The method was fully validated with accuracy, precision, matrix effects, recovery and stability. The validated data have met the acceptance criteria in FDA guideline. The method was applied to a pharmacokinetic interaction study and the results indicated that quetiapine had significant effect on the enhanced plasma exposure of duloxetine in rats under combination use. This study could be readily applied in therapeutic drug monitoring of major depressive disorder patients receiving such drug combinations.

Swirl cooling can provide effective protection for the turbine vane leading edge (LE). In this paper, a swirl cooling model for improving the turbine vane heat transfer is established. The model includes the high-temperature mainstream region, LE region, and swirl cooling region. The conjugate heat transfer (CHT) method is used to examine the influence of wall structures on swirl cooling. Then, the best surface structure in the studied range is selected to further analyze the impact of the coolant inlet mass flow. The results show that the circumferential micro-rib structure has a more excellent performance in both fluid flow and cooling performance. The hindering effect of the micro-ribs can effectively avoid the development of axial cross-flow, thus enhancing the heat transfer with a small friction loss increment and providing a lower surface temperature and more uniform temperature distribution. When the inlet mass flowrate improves, the thermal performance factor increases and the LE temperature decreases gradually. Under the same pumping power condition, the circumferential micro-ribs structure has higher heat transfer efficiency. This investigation can provide a new design for further improving the thermal performance of swirl cooling for turbine vanes.

Affecting the vast majority of human beings, dental caries is a premier concern of worldwide dental health. As the most commonly used restorative material to treat dental caries, resin-based composites (RBCs) lack antibacterial properties leading to quite limited restoration lifetimes. The objective of this study is to develop a polymer–antibiotic conjugate (PAC) as an effective antibacterial additive for RBCs. A monomer–antibiotic conjugate (MAC) with significant solubility was prepared by an esterification reaction of tert-butyloxycarbonyl (Boc)-protected ciprofloxacin (Cip) and 2-hydroxyethyl methacrylate (HEMA). The Cip-containing PAC with well-controlled molecular weight and composition was synthesized by reversible addition–fragmentation chain transfer (RAFT) copolymerization of the MAC with HEMA (1 : 3 molar ratio), followed by the removal of Boc from the resulting copolymer. The antibacterial dental resin was then prepared by incorporating the PAC into a commercial resin, and their properties and antibacterial performance against Streptococcus mutanswere tested. In vitroexperiments revealed a very slow release of Cip, which resulted in significant killing effectiveness against Streptococcus mutansnonetheless, as observed through zone of inhibition assessment and SEM imaging. The promising antibacterial properties of these resins indicate that incorporating a PAC as an additive is a valid strategy to generate antibacterial materials for dental applications.

For a series plug-in hybrid electric vehicle, higher working efficiency can be achieved by the drive system with two small motors in parallel than that with one big motor alone. However, the overly complex structure will inevitably lead to a substantial increase in the development cost. To improve the system price-performance ratio, a new kind of series-parallel hybrid system evolved from the series plug-in hybrid system is designed. According to the technical parameters of the selected components, the system model is established, and the vehicle dynamic property and pure electric drive economy are evaluated. Based on the dynamic programming, the energy management strategy for the drive system under the city driving cycle is developed, and the superiority validation of the system is completed. For the studied vehicle driven by the designed series-parallel plug-in hybrid system, compared with the one driven by the described series plug-in hybrid system, the dynamic property is significantly improved because of the multi-power coupling, and the fuel consumption is reduced by 11.4% with 10 city driving cycles. In a word, with the flexible configuration of the designed hybrid system and the optimized control strategy of the energy management, the vehicle performance can be obviously improved.

•Film cooling of C3X vane with serrate-type trenched holes using mist/air mixture under practical conditions is evaluated.•Both serrated transverse trench structure and addition of mist to air can significantly improve film cooling performance.•Replacing the trench edge by a double-curvature lip structure can further improve the film cooling effectiveness.•Film cooling effectiveness of the vane is reduced when the angle of the serrated trench is too large.•Vortex for the six trenched holes intensifies with the increase in the mass flow rate.

A simple and effective preconcentration method based on magnetic core–shell silica nanoparticles with C18‐modified surface was developed for the analysis of pesticide residues in environmental water samples by gas chromatography‐mass spectrometry. Several kinds of organophosphorous and pyrethroid pesticides including methamidophos, dichlorvos, orthene, phorate, dimethoate, carbofuran, bifenthrin, fenpropathrin, cypermethrin, fenvalerate, and deltamethrin were used as model compounds to systematically evaluate the method. Various parameters, including the amounts of magnetic nanoparticles absorbents, extraction time, eluting solvent, eluting volume, and sample pHvalues were optimized. The optimized method affords low detection limits (signal‐to‐noise ratio = 3) from 0.001 to 0.008 μg/L, and shows good linearity with correlation coefficients over 0.9990 in the concentration range of 0.025–0.5 μg/L. Average recoveries at three spiked levels were in the range of 70.2–110.2% with relative standard deviations below 9.6%. A maximum enrichment factor of 1015 times was achieved. Analysis results of poisoned pond water indicate that this method is fast, convenient, and efficient for the detections of low‐concentration pesticides in aqueous samples.

AbstractEssential oils of rhizome of Polygonum bistortaL. collected from three different Asian regions (Shanghai, China; Guizhou, China, and Lahore, Pakistan) were extracted by hydrodistillation and analyzed by GC-MS. 81 compounds were obtained and 77 were successfully identified. The percentage yield ranged between 0.11 % - 0.29 %. A significant difference in their chemical composition was also found. Major constituents and their percentage ranges were determined as: furfural (0.4 - 16.4 %), oleic acid (4.3 - 8.9 %), oleic acid methyl ester (0.3 - 8.6 %), palmitic acid (4.8 - 6.6 %), 5-methyl furfural (0.5 - 6.5 %), linoleic acid (0.6 - 4.2 %), linoleic acid methyl ester (0.2 - 4.0 %) and cosanes (tetracosane to nonacosane). Similarity tests based on chemometric analysis were performed and results clearly showed the difference in composition among samples. The sample of Pakistani origin and one sample of Chinese origin were separately tested against 2 different bacterial strains and a difference was observed in their antibacterial activities as well.