A new chiral stationary phase for gas chromatography, heptakis (2, 3, 6-tri-O-methoxymethyl)-beta-cyclodextrin, was synthesized by substituting the 2,3,6-OH groups of beta-cyclodextrin with methoxymethyl groups, and a coated capillary column for gas chromatography was made by coating this new stationary phase with static method. The chromatographic properties and separation abilities of the prepared stationary phase were studied. The test results showed that it possessed good separation abilities to Grob test mixture, disubstituted benzene isomers (e. g. nitrotoluenes, bromotoluenes, dichlorobenzenes, dimethylbenzenes) and some chiral compounds such as methyl 2-hydroxypropionates, ethyl 2-hydroxypropionates, methyl 2-methylsulfonylpropionates. The comparison of chiral separation results between 2,3,6-tri-O-methoxymethyl-beta-cyclodextrin and 2,3,6-tri-O-methyl-beta-cyclodextrin showed that the separation abilities of the two stationary phases were different and complementary to each other for some chiral ester enantiomers.
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http://dx.doi.org/10.3724/sp.j.1123.2011.00091 | DOI Listing |
Chaos
January 2025
Department of Control Theory, Scientific and Educational Mathematical Center "Mathematics of Future Technologies", Nizhny Novgorod State University, Gagarin Av. 23, Nizhny Novgorod 603022, Russia.
We consider the effect of the emergence of chimera states in a system of coexisting stationary and flying-through in potential particles with an internal degree of freedom determined by the phase. All particles tend to an equilibrium state with a small number of potential wells, which leads to the emergence of a stationary chimera. An increase in the number of potential wells leads to the emergence of particles flying-through along the medium, the phases of which form a moving chimera.
View Article and Find Full Text PDFOsteoporosis (OP) is a prevalent metabolic bone disease globally. Currently, the development of Traditional Chinese Medicine (TCM) resources to unblock joints, strengthen bones, and enhance muscle function to regulate anti-osteogenic and anabolic metabolism and thus reshape intraosseous homeostasis was an effective way to alleviate OP. The F-E-D formula, comprising Fructus Psoraleae, Eucommia, and Drynariae Rhizoma, has shown efficacy in treating OP.
View Article and Find Full Text PDFHeliyon
January 2025
Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Makkah, 23955, Saudi Arabia.
Antarctica's harsh environmental conditions, characterized by high levels of ultraviolet (UV) radiation, pose challenges for microorganisms. To survive in these extreme cold regions with heightened UV exposure, microorganisms employ various adaptive strategies, including photoprotective carotenoid synthesis. Carotenoids are garnering attention in the skin health industry because of their UV photoprotection potential, given the direct relationship between UV exposure and skin burns, and cancer.
View Article and Find Full Text PDFJ Microbiol Biotechnol
November 2024
Hanyang University ERICA, Ansan 15588, Republic of Korea.
Previous studies showed no improvement in bacterial biomass for Puniceispirillum marinum IMCC1322 under light regimes. Nevertheless, in nutrient-replete cultures with higher inoculating cell densities, strain IMCC1322 exhibited proteorhodopsin photoheterotrophy. Increasing both inoculum size and the amino acid pool can eliminate quorum sensing and starvation responses in strain IMCC1322.
View Article and Find Full Text PDFLight Sci Appl
January 2025
Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, China.
Hanbury-Brown and Twiss (HBT) effect is the foundation for stellar intensity interferometry. However, it is a phase insensitive two-photon interference effect. Here we extend the HBT interferometer by mixing intensity-matched reference fields with the input fields before intensity correlation measurement.
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