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In this work, we suggest a chitosan-modified popcorn-like Au-Ag nanoparticles (CSPNPs) based assay for high sensitive detection of melamine, in which CSPNPs not only provide with an intrinsic peroxidase-like activity but also act ...
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In this work, we suggest a chitosan-modified popcorn-like Au-Ag nanoparticles (CSPNPs) based assay for high sensitive detection of melamine, in which CSPNPs not only provide with an intrinsic peroxidase-like activity but also act as surface enhanced Raman scattering (SERS) substrates. CSPNPs can catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine gm by H2O2 to the charge transfer complex (CTC), which contributes to a tremendous surface-enhanced resonant Raman scattering (SERRS) signals with 632.8 nm laser excitation. The target molecule melamine can generate an additional compound with H2O2, which means the available amount of H2O2 for the oxidation of TMB reduced. Correspondingly, the SERRS intensity of CTC is decreased. The decreased Raman intensity is proportional to the concentration of melamine over a wide range from 10 nM to 50 mu M (R-2=0.989), with a limit of detection CLOD) of 8.51 nM. Moreover, the proposed highly selective method is fully capable of rapid, separation-free detection of melamine in milk powder. (C) 2015 Elsevier B.V. All rights reserved.
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We report here one-pot green synthetic method for preparing popcorn-like Au@Polyluminol nanoflowers by using the HAuCl4 to directly oxidize luminol at a specific controlled mass ratio of HAuCl4: luminol in hydrothermal conditions ...
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We report here one-pot green synthetic method for preparing popcorn-like Au@Polyluminol nanoflowers by using the HAuCl4 to directly oxidize luminol at a specific controlled mass ratio of HAuCl4: luminol in hydrothermal conditions for the first time. The Au@Polyluminol nanoflowers were attached to the surface of a GCE electrode to form a highly solid-state electrochemiluminescent(ECL) sensor, which exhibited strong and stable ECL intensity, showed excellent ECL behavior. Further, the as-prepared Au@Polyluminol nanoflowers could also be used for the immobilization of uricase on an electrode surface to fabricate a sensitive solid-state Uric Acid ECL biosensor, which indicate that the Au@Polyluminol nanoflowers is a promising candidate for constructing various sensitive solid-state ECL sensors and promoting the application in electroanalytical and biochemical analysis. (C) 2018 Elsevier Ltd. All rights reserved.
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2-Acetyltetrahydropyridine is an important flavour constituent that imparts roasty, popcorn-like, and cracker-like odours to foods, such as bread, rice, popcorn, taco shells and tortilla chips. We postulated that the homologue wit...
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2-Acetyltetrahydropyridine is an important flavour constituent that imparts roasty, popcorn-like, and cracker-like odours to foods, such as bread, rice, popcorn, taco shells and tortilla chips. We postulated that the homologue with a formyl group in the C-2 position, 2-formyltetrahydropyridine, might have similar desirable odour qualities. Synthesis of this compound was performed by oxidation of 2-piperi-dinemethanol with silver carbonate supported on Celite~®. This reaction produced a major volatile (46.9% of the total volatiles) with a retention index of 1023 on DB-1. GC-0 revealed that the unknown had a strong cracker-like odour. The electron impact mass spectrum of the unknown had the following major ions: m/z 82, 111, 54, 68, 28, 43. The mjz 53-54 ratio and m/z 82-83 ratio were consistent with a 1,4,5,6-tetrahydropyridine ring structure. GC-FTIR of the unknown revealed an N-H stretching band at 3435 cm~(-1) and a Fermi doublet at 2827 and 2713 cm~(-1) that indicated the presence of an aldehyde. A strong carbonyl absorption band was present at 1703 cm~(-1). The unknown was tentatively identified as 2-formyl-l,4,5,6-tetrahydropyridine, based on its retention index, odour quality, mass spectrum, and vapour phase infrared spectrum.
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In this study, popcorn-shaped with unsmooth surface cadmium sulfide (CdS) nanoparticles were prepared successfully by a facile and convenient one-pot strategy, using PVP-K30 as surfactant. Structure and component of CdS samples we...
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In this study, popcorn-shaped with unsmooth surface cadmium sulfide (CdS) nanoparticles were prepared successfully by a facile and convenient one-pot strategy, using PVP-K30 as surfactant. Structure and component of CdS samples were characterized by XRD and EDX respectively, morphology was studied by SEM and FESEM. The synthetic mechanism of the unsmooth CdS nanospheres was assumed through the above characterization also. From the results, the popcorn-shaped CdS nanoparticles could photocatalytically degrade methyl orange efficiently under visible light irradiation, which is much better than CdS nanoparticles prepared without PVP. These results suggest that the as-prepared CdS nanoparticles might be used as a potential photocatalyst to treat the organic pollutants efficiently under visible light irradiation. (C) 2015 Elsevier B.V. All rights reserved.
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In this paper, novel popcorn balls-like ZnFe2O4/ZrO2 composite microspheres were successfully fabricated by a simple hydrothermal method. The morphology, structure and optical property of the microspheres were characterized; The m...
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In this paper, novel popcorn balls-like ZnFe2O4/ZrO2 composite microspheres were successfully fabricated by a simple hydrothermal method. The morphology, structure and optical property of the microspheres were characterized; The microspheres were used as the photocatalysts to degrade 2,4-dinitrophenol, and exhibited superior photocatalytic performance. Under simulated solar visible light irradiation, the degradation rate of ZnFe2O4/ZrO2 photocatalyst (mass ratio of ZnFe2O4/ZrO2 = 2:1) was almost 7.4 and 2.4 times higher than those of pure ZnFe2O4 and ZrO2. The enhancement could attribute to stronger light absorption, lower carrier recombination and multi-porous structure of the microspheres. Moreover, the popcorn balls-like photocatalysts can be easily separated, because of the magnetism of the samples. After five times runs, the photocatalyst still showed 90% of its photocatalytic degradation efficiency. This work demonstrated a good prospect for removing organic pollutants in water. (C) 2017 Published by Elsevier B.V.
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The monodisperse popcorn-like CeO2 nanostructures with crude surface covered by wrinkles completely and a diameter of 150-300 nm have been successfully synthesized by a facile hydrothermal technology. XRD, SEM, XPS, Raman scatteri...
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The monodisperse popcorn-like CeO2 nanostructures with crude surface covered by wrinkles completely and a diameter of 150-300 nm have been successfully synthesized by a facile hydrothermal technology. XRD, SEM, XPS, Raman scattering and M-H curve were employed to characterize the samples. The results showed that the popcorn-like CeO2 nanostructures have a cubic fluorite structure and there are Ce3+ ions and oxygen vacancies existing in their surface. The magnetic measurement indicated that the popcorn-like CeO2 nanostructures possess excellent ferromagnetism at room temperature, which can be attributed to the influences of the morphology of the particles, Ce3+ ions and oxygen vacancies.
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? 2022 Elsevier Inc.Structure design and assembly control are the two key factors in designing new microwave absorbing materials and improving their electromagnetic wave absorption (EMWA) performance; however, balancing the coordi...
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? 2022 Elsevier Inc.Structure design and assembly control are the two key factors in designing new microwave absorbing materials and improving their electromagnetic wave absorption (EMWA) performance; however, balancing the coordination between these factors remains a great challenge. In this manuscript, a coprecipitation method and an in-situ polymerization method were used to construct nitrogen-carbon-doped popcorn-like porous nanocomposites (NiCoFe/N[sbnd]C). The metallic particles were encapsulated in approximately 10 layers of graphite carbon shells, and a NiCoFe/N[sbnd]C core–shell structure was formed. The EMWA properties of the NiCoFe/N[sbnd]C composites were adjusted by varying the divinylbenzene (DVB) to acrylonitrile (AN) content. The optimized NiCoFe/N[sbnd]C composite showed a minimum reflection loss of ?57.5 dB and a maximum effective absorption bandwidth (EAB) of 5.44 GHz. The excellent EMWA properties of the NiCoFe/N[sbnd]C composites can be attributed to the synergistic effect among the core–shell structure, popcorn-like structure, magnetic metal, carbon and nitrogen. This effect leads to enhanced impedance matching, interface polarization, dipole polarization, multiple reflection and scattering in the composites. In this paper, an effective strategy for the preparation of high-performance magnetic/dielectric composites is provided by carefully designing a new microstructure.
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The hydrogen evolution reaction (HER) holds great promise for clean energy, where electrocatalysts for HER perform as the cathode reaction of water splitting is the critical reaction process on fuel cell. In spite of the rapid gro...
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The hydrogen evolution reaction (HER) holds great promise for clean energy, where electrocatalysts for HER perform as the cathode reaction of water splitting is the critical reaction process on fuel cell. In spite of the rapid growth of alternative materials, platinum (Pt)-based or platinum alloy materials are still the most efficient catalysts for HER. Here, we report a hot-solvent synthesis for producing pop-corn shaped gallium-platinum (GaPt3) nanoparticles, which exhibits intermetallic behavior with abundant uneven surfaces that guarantee the extensive catalytic active edge sites. The electrochemical catalytic activity of GaPt3-based electrode towards HER was demonstrated for the first time, resulting an outstanding performance of only 27 mV overpotential to achieve the 10 mA/cm(2) current density and a Tafel slope of 43.3 mV/dec. (vs. RHE) in acidic media, which is rather superior to that of commercial Pt catalysts and a relatively low overpotential (<80 mV) was obtained even operated at large area (5 cm(2)). Moreover, cycling tests for 10000-cycle CV sweep (-0.3 to 0.2 V vs. RHE) and durability test for 48 h were applied and the performance remains still, thus giving the confirmation to the long-lasting feature of GaPt3 nanoparticles. (C) 2018 Elsevier Ltd. All rights reserved.
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Highly conductive fibers play an essential role in the development of electronic textiles for wearable devices. Even though great progress has been made recently, big challenges of developing simple and rapid methods to prepare fu...
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Highly conductive fibers play an essential role in the development of electronic textiles for wearable devices. Even though great progress has been made recently, big challenges of developing simple and rapid methods to prepare functional fibers with stretchability, high sustainability, and electrical conductivity still remain. Herein, we proposed a simple, rapid, and scalable approach to fabricate stretchable and conductive fibers by growing Au nanostructures on a double-twisted fiber coated with metallic MoS2 nanosheets. The formation of Au nanostructures with a unique "popcorn"-like shape (namely, Au "nanopopcorn", AuNPC) occurs instantaneously and spontaneously on the surface of MoS2-coated fiber, without any additional reducing reagents or heating conditions. Moreover, the overall fabrication process takes less than 5 min, demonstrating the realization of fast fabrication of functional conductive fibers. The obtained fiber with piezoresistive property can be fabricated into a pressure sensor. The unique morphology of AuNPC with a rough surface can significantly enhance the performance of the pressure sensor, with high sensitivity of up to 0.19 kPa(-1) and a fast response time of 93 ms. Furthermore, the functional fiber can be woven into electronic textiles with sensing arrays, which has multiple two-dimensional (2D) force mapping properties. Therefore, we envision that this simple, rapid, and scalable method to fabricate conductive functional fibers would show great potential in the field of electronic textiles and wearable devices.
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In this study, an effective wet-chemical route was developed in an aqueous solution for the synthesis of spindle-like palladium nanoparticles (Pd NPs). Spindle-like Pd NPs in high-yield were successfully synthesized by using cetyl...
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In this study, an effective wet-chemical route was developed in an aqueous solution for the synthesis of spindle-like palladium nanoparticles (Pd NPs). Spindle-like Pd NPs in high-yield were successfully synthesized by using cetyltrimethylammonium chloride (CTAC) as surfactant and ascorbic acid (AA) as reduction reagent. The influence factors including the concentration of CTAC, AA, and NaI, as well as the reaction temperature for synthesis of spindle-like Pd NPs were systematically investigated. The formation mechanism of spindle-like Pd NPs was proposed on the basis of these experimental results. Spindle-like Pd NPs with high density of twins and sharp edges exhibit enhanced catalytic activities for the reduction of 4-nitrophenol.
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