Separation of aromatic components from light cycle oil by solvent extraction

To improve the versatility of light cycle oil (LCO), separation of aromatic compounds from LCO by solvent extraction was investigated. LCO was analyzed to identify 35 components: 19 aromatics and 16 alkanes. The batch liquid–liquid equilibrium extraction of LCO was performed using furfural, sulfolane, and methanol as extraction solvents. In each solvent, the aromatics present in LCO were selectively extracted relative to the alkanes. The separation selectivities of aromatics relative to alkanes were larger in sulfolane than in the other solvents. Among the aromatic components, di- and tricyclic compounds were selectively extracted relative to the monocyclic ones.     

Reduction of Ripple Current Loss by Electromagnetic Coupling of Air‐Core Reactors

To reduce the loss due to ripple current in a multiphase current‐reversible chopper, we investigated electromagnetic coupling of an air‐core reactor. We derived the relationship between the amplitude of the ripple current, the duty factor, and the electromagnetic coupling coefficient, and used the results to estimate the effects of electromagnetic coupling in the design of a train energy storage system. We built reactors with electromagnetic coupling coefficients of 0.93 and 0.60. These reactors employed a new winding structure that provides an optimal electromagnetic coupling coefficient. The mass of the former type of reactor was increased by 4.4% over the conventional design, and that of the latter type of reactor was decreased by 17%. Finally, we tested the new reactors. When the chopper employs the former type of reactor and operates with equal‐phase switching and cumulative coupling, the loss due to ripple current is decreased by 11%. When the chopper employs the latter type of reactor and operates with shift‐phase switching and differential coupling, the loss is decreased to 31%. The test showed that the calculated relationships agreed with the measured values.     

Direct Growth of Germanene at Interfaces between Van der Waals Materials and Ag(111)

Germanene, a 2D honeycomb germanium crystal, is grown at graphene/Ag(111) and hexagonal boron nitride (h-BN)/Ag(111) interfaces by segregating germanium atoms. A simple annealing process in N₂ or H₂/Ar at ambient pressure leads to the formation of germanene, indicating that an ultrahigh-vacuum condition is not necessary. The grown germanene is stable in air and uniform over the entire area covered with a van der Waals (vdW) material. As an important finding, it is necessary to use a vdW material as a cap layer for the present germanene growth method since the use of an Al₂O₃ cap layer results in no germanene formation. The present study also proves that Raman spectroscopy in air is a powerful tool for characterizing germanene at the interfaces, which is concluded by multiple analyses including first-principles density functional theory calculations. The direct growth of h-BN-capped germanene on Ag(111), which is demonstrated in the present study, is considered to be a promising technique for the fabrication of future germanene-based electronic devices.     

Perpendicular oriented cylinders via directional coalescence of spheres embedded in block copolymer films induced by solvent annealing

Polystyrene-b-poly(methyl acrylate) (PS-b-PMA) block copolymer with PS volume fraction of 25.2 vol% was synthesized by atom transfer radical polymerization. Non-pretreated silicon wafers were used as the substrates to prepare perpendicular oriented PS cylinders in PMA matrix via solvent annealing which could induce the transformation of spheres to vertically oriented and hexagonally packed cylinders. The spherical microdomains were formed after the evaporation of solvents from the solutions of the block copolymer in selective solvents mixed from methanol, acetone and dichloromethane. The thickness of films could be as thick as 1000 nm, which were much thicker than usual cases and the cylinders came from the directional coalescence of the spheres, thus any pre-treatments of the substrates were not required for perpendicular orientation. The structures were characterized by small angle X-ray scattering (SAXS), transmission electron microscope (TEM), atom force microscopy (AFM) and grazing incidence small angle X-ray scattering (GISAXS).     

Use of multivariate analysis for the improvement in prediction accuracy of bacterial aerobic plate count by flow cytometry

Flow cytometry (FCM) and aerobic plate count (APC) by the culture method were performed on green tea samples spiked with Escherichia coli type strain NCTC9001 (ATCC11775) solutions of different concentrations. In FCM, fluorescence signals from multiple stained bacteria and other fluorophores are detected using detector channels, and recorded as events with a voltage at each channel. FCM data were analyzed in two ways: conventional and multivariate analysis. In the former, the number of events with voltages larger than the defined threshold values was regarded as the predicted APC. In the latter, voltage histograms of all channels were obtained and merged horizontally to serve as explanatory variables. Then a partial least squares regression (PLSR) model was built to predict APC from the histogram data. The coefficient of determination (R²) and the root mean square error (RMSE) between APC by the culture method and that predicted by conventional FCM were 0.916 and 1.08 cfu/ml². The APC values predicted by the PLSR model and those measured were in good agreement with R² of 0.982 and RMSE of 0.417 cfu/ml, which verified the potential of the proposed method for improving APC prediction accuracy by FCM.     

Effect of α-substituents on molecular motion and wetting behaviors of poly(fluoroalkyl acrylate) thin films with short fluoroalkyl side chains

The effect of α-substituent on the molecular motion and wetting behavior of poly{2-(perfluorobutyl)ethyl acrylate} [PFA-C₄], poly{2-(perfluorobutyl)ethyl methacrylate} [PFMA-C₄], poly{2-(perfluorobutyl)ethyl α-fluoroacrylate} [PFFA-C₄], and poly{2-(perfluorobutyl)ethyl α-chloroacrylate} [PFClA-C₄] films were characterized by dynamic contact angle measurement, lateral force microscopy (LFM), wide angle X-ray diffraction (WAXD), and X-ray photoelectron spectroscopy (XPS). WAXD of oriented PFClA-C₄ fiber suggested the presence of rod-like chain due to the presence of bulky α-substituent. The glass transition temperature (T_g) of PFFA-C₄ and PFClA-C₄ were well above the room temperature. The water repellencies of PFFA-C₄ and PFClA-C₄ were as high as that of PFMA-C₄ and their oil repellency of PFFA-C₄ and PFClA-C₄ was higher than the PFMA-C_4. This result was originated from the low main chain mobility of PFFA-C₄ and PFClA-C₄ due to the presence of bulky α-substituents. The effect of molecular motion on water repellency was clarified by the results of temperature dependence studies of dynamic contact angle, LFM, and surface chemical composition measured by XPS.     

Computer-generated Conversation Using Newspaper Headline

In this paper, the authors propose a method that incorporates mechanisms for handling ambiguity in speech and the ability of humans to create associations, and for formulating conversations based on rule base knowledge and common knowledge. Go beyond the level that can be achieved, using only conventional natural language processing and vast repositories of sample patterns. In this paper, the authors propose a method for computer conversation sentences generated using newspaper headlines as an example of how the common knowledge and associative ability are applied.