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This article presents the research results in the application of image processing in determining the position, direction, and moving speed of different objects when they move in the free space in the field of view of measuring cameras. The research includes developing an algorithm to detect, identify, and locate objects and an algorithm to calculate the movement direction and instantaneous velocity of the object. Two robots with measurement systems were designed for testing, one carries the investigating object, and the other the camera. These robots can communicate with a computer system using a tele-wireless system. A program was also built for capturing images and analyzing the state of the model automatically. Experimental results show that the position, angle, and velocity of different objects can be captured well. The average error in determining the direction of movement is an average of 1.25°, and the error of the moving speed is less than 0.5 m/s. The research results provide a potential tool for designing robots for highly effective detection. The algorithm and the measurement system are simple and inexpensive but highly effective, and they can be used in the initial process of determining an object. A detailed description of the algorithm, robot system, and testing will be presented in this study. [ABSTRACT FROM AUTHOR]

Normal‐phase (NP) liquid chromatography is one of the most effective methods for separating isomers with sensitive structural features, including xanthophyll isomers. In this work, reverse‐phase (RP) and NP liquid chromatography (LC), with silica gel and diol phase, respectively, were evaluated for the separation of xanthophyll isomers. The results showed that RP LC with monomeric C18 phase not only poorly separate all xanthophyll isomers in egg yolk but also requires additional sample preparation to eliminate triacylglycerols in egg yolk. The diol phase of NP‐LC provided the highest efficiency for separating lutein, zeaxanthin, and their cis‐isomers with isocratic separation using mobile phases consisting of n‐hexane and polar modifiers (such as acetone, methyl tert‐butyl ether, or ethyl acetate). To determine the xanthophyll content, peak areas from LC and total absorbance from spectrophotometry measurements were used. The approach was applied to analyze the xanthophylls of nine commercial egg samples. The results revealed that five out of nine analyzed samples contained a high level of canthaxanthin, which contributes to color enhancement but not to prevent age‐related macular degeneration. Together, it shows that NP LC with diol phase combined with spectrophotometry is a powerful tool to monitor xanthophylls in eggs. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to explore how entrepreneurial culture (EC) and psychological empowerment (PE) support innovative work behaviour (IWB) of employees in organizations. First, it examines the impact of EC on IWB. It also explores the mediating effect of PE to support the EC – IWB relationship. Accordingly, it suggests a mechanism model to explain the relationship between EC and IWB. Design/methodology/approach: This is an empirical research using quantitative methods. Data were collected via both face-to-face and online surveys from 308 employees in Vietnamese enterprises. The partial least squares-based structural equation modelling (PLS-SEM) approach was applied to test hypotheses in the research model. Findings: Significant R-square values were achieved for both EC – PE and PE – IWB relationships, according to the PLS-SEM. The most interesting finding is the full mediating role of PE in the relationship between EC and IWB. Despite the non-significance in the direct impact of EC on IWB, the role of EC in promoting IWB is important in an indirect way through PE. The significant role of PE in facilitating IWB has been proven. Originality/value: This research is one of the initial attempts to empirically build the roadmap from EC, as a typical type of organizational culture, through the mediating effect of PE to improve IWB. This roadmap provides top managers with a hierarchical view that effectively cascading interventions from the organizational level, such as EC, through a significant mediator as PE at the group level, and then down to IWB as a result at the individual level. [ABSTRACT FROM AUTHOR]

The present work aimed to investigate inclusion complexes of squalene with various cyclodextrins (native β-cyclodextrin and methyl-β-cyclodextrin). The production of squalene-β-cyclodextrin inclusion complex was obtained using Response Surface Methodology and obtained inclusion complexes were studied with FTIR spectroscopy, X-ray diffractometry, thermal analysis, and 1 H-NMR spectrometry. At the same time, squalene content was determined by reversed-phase high-performance liquid chromatography. All results confirmed that squalene was successfully involved in the cyclodextrin cavities. Optimizing the condition in preparation for the squalen-β-cyclodextrin inclusion complex yielded 54.3% with squalene content of 9.01%. The essential difference for the inclusion complex of squalene with methylated beta-cyclodextrin was that no precipitate formed in the initial mixture, and the complex was more efficiently dispersed in water. The conclusions of the inclusion complex formation were confirmed by computer simulation by optimizing the complex geometry using the DFT, MM2, and MP3 methods. [ABSTRACT FROM AUTHOR]

Polyaniline nanowires are directly synthesized on a glassy carbon electrode (3 mm diameter) by an electrochemical process. The polyaniline nanowires, of uniform size, a diameter of 85–95 nm, and high conductivity, distribute evenly throughout the surface of the working electrode. Electrochemical measurements are conducted in order to determine the electrochemically effective surface area of the obtained glassy carbon electrode modified with polyaniline nanowires, and an investigation of the electrocatalytic activity of polyaniline nanowires for the oxidation of methanol under alkaline conditions is carried out. The electrochemically effective surface area of the glassy carbon electrode modified with polyaniline nanowires is nearly 27 times larger than that of a glassy carbon electrode. In a cyclic voltammetry curve of the glassy carbon electrode modified with polyaniline nanowires measured in a 3.0 M CH3OH and 0.5 M KOH solution, an anodic peak corresponding to the oxidation of methanol under alkaline conditions appears at 0.17 V with a peak current of 34.4 μA. [ABSTRACT FROM AUTHOR]

An integrated software for calculating the major mechanical properties of materials was newly programmed. The material mechanical properties are determined from a peak position and the broadness of X-ray diffraction (XRD) line using profile function method, including Gaussian, Parabola, Half-width, and Centroid. The X-ray diffraction line in software is also corrected by the generalized X-ray absorption function. The results show that the precision coefficient (R2) of the dhkl-sin2 ψ linear regression depends on tested materials and the method of the 2θ determination. The Parabola and Gaussian methods show greater fitting accuracy in comparison to the other two methods in determining stress. The mechanical properties calculated using this software agreed well with the values determined from the conventional methods. In addition, this XRD software also allows computing the 95% confidential limits of the results from a single measurement without conducting repetitive measurements. Therefore, the new software allows widening the experimental scopes of an X-ray diffraction device in both laboratories and the industrial sector. [ABSTRACT FROM AUTHOR]

Surfactants are critical to many areas thanks to their characteristic adsorption property and surface activities; therefore, the understanding of their adsorption behaviors at interfaces is highly desirable. Typically, the adsorption of surfactants at the air/water interface has been interpreted based on monolayer models. However, recent studies have controversially proposed that there exists sub-monolayer adsorption underneath the air/water interface at surfactant concentrations well below its critical micelle concentration. In this report, we provide several pieces of experimental evidence to validate the presence of such sub-monolayer adsorption through laser scattering experiments on sodium dodecyl sulfate (SDS) adsorption at the air/water interfaces of ultrafine gas bubbles. In addition, by employing the calculation of the total surface area and Mie cross section, the Gibbs model was demonstrated to be inappropriate for SDS adsorption in bubble enriched solutions. Also, sum-frequency generation vibrational spectroscopy further reinforced the existence of the sub-adsorption layer instead of an adsorption monolayer. We believe that this work provides strong evidence supporting the existence of sub-monolayer adsorption which can be combined with other intrinsic surface-sensitive techniques to elucidate this phenomenon at the air/water interface. [ABSTRACT FROM AUTHOR]

Three novel bis- and trinitroso compounds derived from 1,3,5- trihydrohybenzene (phloroglucinol), 2,4,6–trihydroxy benzoic acid, and 2,4,6-trihydroxyacetophenone were isolated, their spectral characteristics, ionization constants and thermodynamic parameters of dissociation process were calculated. The comparison of the stability of nitroso and hydroxylimino tautomeric forms was performed by DFT calculations. Nine complexes of the ligands with Cu(II), Cd(II), and Fe(III), were isolated and studied by elemental analyses, X Ray analysis and spectroscopic methods. According to the crystal structure determination, the Cd complex with the phloroglucinol based ligand exists in the form of a binuclear compound. The QTAIM Bader topological analysis indicated that the binuclearity of the Cd complex is due to strong interatomic interactions between Cd atoms with bifurcate carbonyl groups of the ligands and strong H-interactions involving coordinated and lattice water molecules. The equilibria of reactions of complex formation of the organic species with Cu2+, Cd2+, and Fe3+ was studied by spectrophotometric titration, and the composition of the complexes in solutions and their stability constants were calculated. The ability of the isolated organics to remove metal cations from the aqueous solutions was studied in the pH interval 3–6 and the rate of Cu2+ removal from aqueous solutions was found close to 100%. [ABSTRACT FROM AUTHOR]

A model is proposed for the surface structure of reversed phase sorbents obtained via the chemical modification of silica gel with alkyldimethylchlorosilanes. The structure of the surface is consistent with the known data on the properties of silica gel and n-alkanes. The model notes that the coupling of silicon-oxygen tetrahedra (silica gel structural units) is such that the tetrahedra alternate in the order top up/top down. At the same time, the number of surface silanol groups on the model's surface, which can be obtained for the orthorhombic structure of cristobalite, is close to the experimental value (slightly less than five groups per nm2). By comparing the parameters of such a surface and those of alkane packing in the solid phase, it is concluded that all surface silanol groups can be subjected to derivatization according to a hydride scheme. However, due to steric reasons (the presence of two methyl groups in the anchor group), only half the surface groups can be replaced upon silylating the surface of silica gel with alkyldimethylchlorosilane. At the same time, alkyl groups of sorbates or planar molecules can easily be introduced into the graft phase with no need for the conformational rearrangement of grafted alkyl radicals. [ABSTRACT FROM AUTHOR]

This paper investigates the friction coefficient of a moving liquid marble, a small liquid droplet coated with hydrophobic powder and floating on another liquid surface. A floating marble can easily move across water surface due to the low friction, allowing for the transport of aqueous solutions with minimal energy input. However, the motion of a floating marble has yet to be systematically characterised due to the lack of insight into key parameters such as the coefficient of friction between the floating marble and the carrier liquid. We measured the coefficient of friction of a small floating marble using a novel experimental setup that exploits the non-wetting properties of a liquid marble. A floating liquid marble pair containing a minute amount magnetite particles were immobilised and then released in a controlled manner using permanent magnets. The capillarity-driven motion was analysed to determine the coefficient of friction of the liquid marbles. The 'capillary charge' model was used to fit the experimental results. We varied the marble content and carrier liquid to establish a relationship between the friction correction factor and the meniscus angle. [ABSTRACT FROM AUTHOR]