The combination of surface coils and metamaterials remarkably enhance magnetic resonance imaging (MRI) performance for significant local staging flexibility. However, due to the coupling in between, impeded signal-to-noise ratio (SNR) and low-contrast resolution, further hamper the future growth in clinical MRI. In this paper, we propose a high-Q metasurface decoupling isolator fueled by topological LC loops for 1.
View Article and Find Full Text PDFIn this study, a nickel-vanadium layered double hydroxide (NiV-LDH) nanosheet was prepared as a saturable absorber (SA) by liquid phase exfoliation and a drop-coating method. The microstructure and optical transmission properties of the obtained NiV-LDH nanosheet were then systematically studied. An "X"-type fold cavity was designed to evaluate the ultrafast laser modulation performance of the NiV-LDH nanosheet with a Tm:YAG ceramic gain medium.
View Article and Find Full Text PDFAiming at the challenge that environmental protection and high-temperature fluid loss reduction performance of the traditional water-based drilling fluid treatment agent are difficult to balance, our studies added psyllium husk as a high-temperature-resistant and environmentally friendly filtrate reducer to a water-based drilling fluid. The composition, physical and chemical properties, and microstructure of psyllium husk are characterized. Then, the effects of psyllium husk after hot rolling at different temperatures on the rheological properties and fluid loss properties of bentonite-based slurry are evaluated.
View Article and Find Full Text PDFThe development of offshore oil and gas requires environmental protection during the drilling process. However, the existing drilling fluid additives cannot form an efficient environmentally friendly drilling fluid system. At the same time, some environmentally friendly drilling fluid additives cannot be widely used due to their high cost and complicated production process.
View Article and Find Full Text PDFThermosensitive polymer hydrogel particles with size varying from 480 to 620 nm were prepared through precipitation copolymerization of N-isopropylacrylamide with N,N'-methylenebisacrylamide (MBA) in water with ammonium persulfate as the initiator. Only polymer hydrogels without any coagula were obtained when MBA concentration in the monomer mixture was kept between 2.5 and 10.
View Article and Find Full Text PDFWith dodecanol (C12OH) as a model molecule of insect sex pheromone as core material, natural polymers gelatin (GE) and acacia gum (AG) as wall materials, microcapsules aiming to be a sprayable environment-friendly pesticide were prepared via GE simple coacervation and complex coacervation of GE and AG. C12OH encapsulation in complex coacervation was higher than those in simple coacervation. Its encapsulation was enhanced with increase in wall material cross-linking.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
March 2006
A kind of amphiphilic derivatives of chitosan (2-hydroxyl-3-butoxyl)-propylcarboxymethyl-chitosan (HBP-CMCHS), has been synthesized, and the critical micelle concentration (cmc) of HBP-CMCHS was detected by the fluorescence method. The puerarin-loaded HBP-CMCHS micellar system was prepared by physical entrapped method. Result showed that when adding the same amount of puerarin, the solubilizing capacity was enhanced by increasing the concentration of HBP-CMCHS and temperature.
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