Rogue wave solutions for a generalized nonautonomous nonlinear equation in a nonlinear inhomogeneous fiber

In this paper, we investigate a generalized nonautonomous nonlinear equation which describes the ultrashort optical pulse propagating in a nonlinear inhomogeneous fiber. By virtue of the generalized Darboux transformation, the first- and second-order rogue-wave solutions for the generalized nonautonomous nonlinear equation are obtained, under some variable–coefficient constraints. Properties of the first- and second-order rogue waves are graphically presented and analyzed: When the coefficients are all chosen as the constants, we can observe the some functions, the shapes of wave crests and troughs for the first- and second-order rogue waves change. Oscillating behaviors of the first- and second-order rogue waves are observed when the coefficients are the trigonometric functions.     

Rapid determination of α‐tocopherol in cereal grains using dispersive liquid–liquid microextraction followed by HPLC

The traditional for the determination of α‐tocopherol in cereal grains includes saponification of a sample followed by liquid–liquid extraction, and it is time‐ and solvent consuming. In this study, a dispersive liquid–liquid microextraction (DLLME) method was developed to extract α‐tocopherol in situ from the saponified grain sample solution. The DLLME experimental parameters including the type and volume of extractants, the volume of dispersers, the addition of salt and the extraction/centrifuging time were examined and optimized. The recommended analytical procedure showed excellent precision (relative SDs of the α‐tocopherol amount of 3.1% over intraday and 7.2% over interday), high sensitivity (the detection limit of 1.9 ng/mL), and strong recovery values (88.9–102.5%). In addition, statistical analyses showed no significant difference between the detected amounts of α‐tocopherol found by the standardized method and this new procedure. The method was successfully applied to determining the amounts and distribution of α‐tocopherol in 14 cereal grain samples.     

Coagulation behaviors and in-situ flocs characteristics of composite coagulants in cyanide-containing wastewater: Role of cationic polyelectrolyte

In this paper,composite coagulants(PFS,PFSC05,PFSC1 and PFSC5),prepared by mixing polyferric sulfate(PFS)and cationic polyelectrolyte(CP)coagulants with different weight percent(Wp)of CP(Wp=0%,0.5%,1%and 5%,respectively),were adopted to treat cyanide-containing wastewater.PFSC5 exhibited superior coagulation performances at optimal conditions:the removal of total cyanide(TCN)and chemical oxygen demand(COD)was 95%–97%and 50%–55%,respectively.The effects of CP on the properties and structure of flocs were investigated by laser diffraction instrument and small-angle laser light scattering(SALLS),respectively.The results show that the flocs of PFSC5 have higher growth rate,higher strength factor and lower recovery factor than other flocs.They are also much denser and more uniform owing to the higher fractal dimension(Df)and less microflocs(10–100 m).Furthermore,the dense structure of the PFSC5 flocs can be restored after shear and is more resistant to hydraulic conditions.Particularly,detailed morphology evolution of the flocs was in-situ detected by on-line particle imaging.Due to strong ionic strength in wastewater,the CP in PFSC5 plays a significant role of adsorption,while the main mechanism of CP is electrostatic patch aggregation during the PFSC05 systems.     

Novel Route to Functionalized Indans via Formal [3 + 2] Cycloadditions of 1-Benzylbenzotriazoles with Alkenes

α-Functionalized 1-benzylbenzotriazoles (3, 4 and 12), derived from the lithiation of 1-(2,3-dimethoxybenzyl)benzotriazole 2 followed by reactions with electrophiles, or from the condensation of benzyl alcohol 11 with benzotriazole, undergo formal [3 + 2] cycloadditions with styrenes upon treatment with ZnBr₂ to give functionalized indans (9, 10, 13 and 14).     

Direct Blue 71 staining as a destaining‐free alternative loading control method for Western blotting

In Western blotting, a suitable loading control is indispensable for correcting errors in the total amount of loaded protein. Immunodetection of housekeeping proteins and total protein staining have traditionally been used as loading control methods. Direct Blue 71 (DB71) staining—a novel, sensitive, dye‐binding staining method compatible with immunodetection—may offer advantages over these traditional loading control methods. Three common neuroscientific samples (human plasma, human oligodendrocytes, and rat brain) were employed to assess DB71 staining as a loading control method for Western blotting. DB71, CBB, one traditional housekeeping protein, and one protein of interest were comparatively assessed for reliability and repeatability and linear dynamic range over 2.5–40 μg of protein loaded. DB71's effect on the reliability and repeatability and linear dynamic range of immunoreaction were also assessed. Across all three sample types, DB71 was either equivalent or superior to CBB and housekeeping protein‐based methods in terms of reliability and repeatability and linear dynamic range. Across all three sample types, DB71 staining did not impair the reliability and repeatability or linear dynamic range of immunoreaction. Our results demonstrate that the DB71 staining can be used as a destaining‐free alternative loading control method for Western blotting.     

Thermodynamics of AOT Micelle Formation in Ethylammonium Nitrate

AOT micelle formation in ethylammonium nitrate (an ionic liquid) was investigated by surface tension measurement in this article and the critical micelle concentrations (cmc) of AOT in ethylammonium nitrate at different temperatures were obtained. The thermodynamic parameters of micelle formation were obtained according to the two-phase thermodynamic model. The results suggested that the micelle formation of AOT in ethylammonium nitrate was a spontaneous, endothermal and entropy-increasing process.     

Transparent conducting Sn:ZnO films deposited from nanoparticles

Homogeneous transparent conducting Sn:ZnO films on fused silica substrates were prepared by dip-coating from nanoparticle dispersions, while the nanocrystalline Sn:ZnO particles with different dopant concentrations were synthesized by microwave-assisted non-aqueous sol–gel process using Sn(IV) tert-butoxide and Zn(II) acetate as precursors and benzyl alcohol as solvent. The dopant concentration had a great impact on the electrical properties of the films. A minimum resistivity of 20.3 Ω cm was obtained for a porous Sn:ZnO film with initial Sn concentration of 7.5 mol% after annealing in air and post-annealing in N₂ at 600 °C. The resistivity of this porous film could further be reduced to 2.6 and 0.6 Ω cm after densified in Sn:ZnO and Al:ZnO reaction solution, respectively. The average optical transmittance of a 400-nm-thick Sn:ZnO film densified with Sn:ZnO after the two annealing steps was 91%.     

Exploring the Reactivity of Multicomponent Photocatalysts: Insight into the Complex Valence Band of BiOBr

The band structure of multicomponent semiconductor photocatalysts, as well as their reactivity distinction under different wavelengths of light, is still unclear. BiOBr, which is a typical multicomponent semiconductor, may have two possible valence‐band structures, that is, two discrete valence bands constructed respectively from O 2p and Br 4p orbitals, or one valence band derived from the hybridization of these orbitals. In this work, aqueous photocatalytic hydroxylation is applied as the probe reaction to investigate the nature and reactions of photogenerated holes in BiOBr. Three organic compounds (microcystin‐LR, aniline, and benzoic acid) with different oxidation potentials were selected as substrates. Isotope labeling (H₂¹⁸O as the solvent) was used to determine the source of the O atom in the hydroxyl group of the products, which distinguishes the contribution of different hydroxylation pathways. Furthermore, a spin‐trapping ESR method was used to quantify the reactive oxygen species (^.OH and ^.OOH) formed in the reaction system. The different isotope abundances of the hydroxyl O atom of the products formed, as well as the reverse trend of the ^.OH/^.OOH ratio with the oxidative resistance of the substrate under UV and visible irradiation, reveal that BiOBr has two separate valence bands, which have different oxidation ability and respond to UV and visible light, respectively. This study shows that the band structure of semiconductor photocatalysts can be reliably analyzed with an isotope labeling method.     

Cyclized oligomer of tetracyanoquinodimethane-tetrathiafulvalene (TCNQ-TTF): a versatile macrocyclic molecule by DFT calculations

Journal of Inclusion Phenomena and Macrocyclic Chemistry - The combination of the electron donor and acceptor into a donor–acceptor system can transform the intermolecular charge transfer...