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Phase diagrams of materials are typically based on a static order parameter, but it faces challenges when distinguishing subtle phase changes, such as reordering. Here, we report a dynamic nonequilibrium order parameter termed re-order parameter to determine subtle phases and their transitions in interacting magnets. The dynamical precession of magnetization, so-called magnon, premises as a reliable re-order parameter of strong spin-orbit coupled magnets. We employ orthoferrites YFeO3 and its Mn-doped variations, where diverse magnetic phases, including canted antiferromagnetic (Γ4) and collinear antiferromagnetic (Γ1) states, have been well-established. Low-energy magnon uncovers the spin-orbit coupling-induced subtle magnetic structures, resulting in distinct terahertz emissions. The temporal and spectral parameters of magnon emission exhibit characteristics akin to BCS-type order parameters, constructing the magnetic phase diagram of Mn-doped YFeO3. This approach further reveals a concealed ferrimagnetic phase within the Γ1 state, underscoring its potential to search for hidden phases of materials, completing their phase diagrams. [ABSTRACT FROM AUTHOR]

Encoded particles have a demonstrated value for multiplexed high-throughput bioassays such as drug discovery and clinical diagnostics. In diverse samples, the ability to use a large number of distinct identification codes on assay particles is important to increase throughput. Proper handling schemes are also needed to readout these codes on free-floating probe microparticles. Here we create vivid, free-floating structural coloured particles with multi-axis rotational control using a colour-tunable magnetic material and a new printing method. Our colour-barcoded magnetic microparticles offer a coding capacity easily into the billions with distinct magnetic handling capabilities including active positioning for code readouts and active stirring for improved reaction kinetics in microscale environments. A DNA hybridization assay is done using the colour-barcoded magnetic microparticles to demonstrate multiplexing capabilities. [ABSTRACT FROM AUTHOR]

Oxidative dehydrogenation of n-butene to 1,3-butadiene over sulfated ZnFe2O4 catalyst was carried out in a continuous flow fixed-bed reactor. The effect of sulfation on the catalytic performance of ZnFe2O4 was investigated. Sulfated ZnFe2O4 catalyst showed a better catalytic performance than ZnFe2O4 catalyst in the oxidative dehydrogenation of n-butene. Acid–base property of sulfated ZnFe2O4 catalyst was measured by TPD experiment, with an aim of correlating the catalytic performance with the surface acid–base property of the catalyst. It was revealed that the catalytic performance of sulfated ZnFe2O4 catalyst was closely related to the surface weak-acid density of the catalyst. The enhanced acidity of sulfated ZnFe2O4 catalyst was responsible for its high catalytic performance in the oxidative dehydrogenation of n-butene. Thus, sulfation served as an efficient method for improving catalytic performance of ZnFe2O4 in the oxidative dehydrogenation of n-butene. [ABSTRACT FROM AUTHOR]

γ-Bi2MoO6 catalysts prepared by a co-precipitation method were calcined at various temperatures (425–675 °C), and were applied to the oxidative dehydrogenation of n-butene to 1,3-butadiene in a continuous flow fixed-bed reactor. Conversion of n-butene and yield for 1,3-butadiene were high at low calcination temperature (425–475 °C), but were decreased with increasing calcination temperature (525–675 °C). Temperature-programmed reoxidation (TPRO) measurements revealed that the catalytic performance of γ-Bi2MoO6 was well correlated with the oxygen mobility of the catalyst. Yield for 1,3-butadiene was increased with increasing oxygen mobility of γ-Bi2MoO6 catalyst. Among the catalysts tested, γ-Bi2MoO6 catalyst calcined at 475 °C showed the best catalytic performance due to its facile oxygen mobility. [ABSTRACT FROM AUTHOR]

ZnMeIIIFeO4 catalysts with different trivalent metal (MeIII = Fe, Al, Cr, Mn, and Co) were prepared by a co-precipitation method, and were applied to the oxidative dehydrogenation of n-butene to 1,3-butadiene. Successful formation of ZnMeIIIFeO4 catalysts was confirmed by XRD and ICP-AES analyses. Catalytic performance of ZnMeIIIFeO4 catalysts in the oxidative dehydrogenation of n-butene strongly depended on the identity of trivalent metal (MeIII). Acid properties of ZnMeIIIFeO4 catalysts were measured by NH3-TPD experiments, with an aim of correlating the catalytic performance with the surface acid property of the catalysts. It was revealed that yield for 1,3-butadiene increased with increasing surface weak-acid density of ZnMeIIIFeO4 catalyst. Among the catalysts tested, ZnFeFeO4 catalyst with the largest surface weak-acid density showed the best catalytic performance in the oxidative dehydrogenation of n-butene. [ABSTRACT FROM AUTHOR]

Many creatures in nature, such as butterflies and peacocks, display unique brilliant colours, known as ‘structural colours’, which result from the interaction of light with periodic nanostructures on their surfaces. Mimicking such nanostructures found in nature, however, requires state-of-the-art nanofabrication techniques that are slow, expensive and not scalable. Herein, we demonstrate high-resolution patterning of multiple structural colours within seconds, based on successive tuning and fixing of colour using a single material along with a maskless lithography system. We have invented a material called ‘M-Ink’, the colour of which is tunable by magnetically changing the periodicity of the nanostructure and fixable by photochemically immobilizing those structures in a polymer network. We also demonstrate a flexible photonic crystal for the realization of structural colour printing. The simple, controllable and scalable structural colour printing scheme presented may have a significant impact on colour production for general consumer goods. [ABSTRACT FROM AUTHOR]

ZnMeIIIFeO4 catalysts with different trivalent metal (MeIII = Fe, Al, Cr, Mn, and Co) were prepared by a co-precipitation method, and were applied to the oxidative dehydrogenation of n-butene to 1,3-butadiene. Successful formation of ZnMeIIIFeO4 catalysts was confirmed by XRD and ICP-AES analyses. Catalytic performance of ZnMeIIIFeO4 catalysts in the oxidative dehydrogenation of n-butene strongly depended on the identity of trivalent metal (MeIII). Acid properties of ZnMeIIIFeO4 catalysts were measured by NH3-TPD experiments, with an aim of correlating the catalytic performance with the surface acid property of the catalysts. It was revealed that yield for 1,3-butadiene increased with increasing surface weak-acid density of ZnMeIIIFeO4 catalyst. Among the catalysts tested, ZnFeFeO4 catalyst with the largest surface weak-acid density showed the best catalytic performance in the oxidative dehydrogenation of n-butene. [ABSTRACT FROM AUTHOR]

Recent progress on the bismuth molybdate catalysts for oxidative dehydrogenation of n-butene to 1, 3-butadiene was reported in this review. A number of bismuth molybdate catalysts, including pure bismuth molybdates (α-Bi2Mo3O12, β-Bi2Mo2O9, and γ-Bi2MoO6) and multicomponent bismuth molybdates, were prepared by a co-precipitation method for use in the production of 1,3-butadiene from C4 raffinate-3 through oxidative dehydrogenation of n-butene. It was observed that multicomportent bismuth molybdate catalyst was more efficient than pure bismuth molybdate catalyst in the oxidative dehydrogenation of n-butene. Various experimental measurements such as temperature-programmed reoxidation, X-ray photoelectron spectroscopy, and O2-temperatureprogrammed desorption analyses were carried out to elucidate the different catalytic activity of bismuth molybdate catalysts. It was revealed that a bismuth molybdate catalyst with a higher oxygen mobility showed a better catalytic performance in terms of conversion of n-butene and yield for 1,3-butadiene. We have successfully demonstrated from experimental findings that oxygen mobility of bismuth molybdate catalyst played a key role in determining the catalytic performance in the oxidative dehydrogenation of n-butene to 1,3-butadiene. [ABSTRACT FROM AUTHOR]

Co9Fe3Bi1Mo12O51 catalysts were prepared by a co-precipitation method at different pH (pH = 1–7), and were applied to the oxidative dehydrogenation of n-butene to 1,3-butadiene in a continuous flow fixed-bed reactor. Conversion of n-butene and yield for 1,3-butadiene over Co9Fe3Bi1Mo12O51 catalysts showed volcano-shaped curves with respect to co-precipitation pH value. O2-TPD (temperature-programmed desorption) measurements revealed that the catalytic performance of Co9Fe3Bi1Mo12O51 was closely related to the oxygen mobility of the catalyst. Yield for 1,3-butadiene was increased with increasing oxygen mobility of the catalyst. Among the catalysts tested, Co9Fe3Bi1Mo12O51 catalyst prepared at pH 3 showed the best catalytic performance due to its highest oxygen mobility. The pH value during the co-precipitation step strongly affected the oxygen mobility of Co9Fe3Bi1Mo12O51 catalysts, and in turn, the oxygen mobility played a key role in determining the catalytic performance of Co9Fe3Bi1Mo12O51 catalysts in the oxidative dehydrogenation of n-butene. [ABSTRACT FROM AUTHOR]

Pure bismuth molybdate (γ-Bi2MoO6) and multicomponent bismuth molybdate (Co9Fe3Bi1Mo12O51) catalysts were prepared by a co-precipitation method, and were applied to the oxidative dehydrogenation of n-butene to 1,3-butadiene. The Co9Fe3Bi1Mo12O51 catalyst showed a better catalytic performance than the γ-Bi2MoO6 catalyst in terms of conversion of n-butene and yield for 1,3-butadiene, indicating that the multicomponent bismuth molybdate was more efficient than the pure bismuth molybdate in the oxidative dehydrogenation of n-butene. It was revealed that the crucial factor determining the catalytic performance of Bi–Mo-based catalyst in the oxidative dehydrogenation of n-butene is not the amount of oxygen in the catalyst involved in the reaction (oxygen capacity) but the intrinsic mobility of oxygen in the catalyst involved in the reaction (oxygen mobility). The enhanced catalytic performance of Co9Fe3Bi1Mo12O51 was due to its facile oxygen mobility. [ABSTRACT FROM AUTHOR]

A series of metal ferrite (MeIIFe2O4) catalysts were prepared by a co-precipitation method with a variation of divalent metal component (MeII = Zn, Mg, Mn, Ni, Co, and Cu) for use in the oxidative dehydrogenation of n-butene to 1,3-butadiene. Successful formation of metal ferrite catalysts with a random spinel structure was confirmed by XRD, ICP-AES, and XPS analyses. The catalytic performance of metal ferrite catalysts in the oxidative dehydrogenation of n-butene strongly depended on the identity of divalent metal component. Acid properties of metal ferrite catalysts were measured by NH3-TPD experiments, with an aim of correlating the catalytic performance with the acid property of the catalysts. It was revealed that the yield for 1,3-butadiene increased with increasing surface acidity of the catalyst. Among the catalysts tested, ZnFe2O4 catalyst with the largest surface acidity showed the best catalytic performance in the oxidative dehydrogenation of n-butene. [ABSTRACT FROM AUTHOR]

Oxidative dehydrogenation of C4 raffinate-3 to 1,3-butadiene was carried out in a dual-bed reaction system comprising ZnFe2O4 and Co9Fe3Bi1Mo12O51 catalysts in order to investigate a synergistic effect of these two catalysts. Conversion of n-butene and yield for 1,3-butiadene obtained in a dual-bed reaction system comprising ZnFe2O4 (first-bed) and Co9Fe3Bi1Mo12O51 (second-bed) were higher than those obtained in a single-bed reaction system using either ZnFe2O4 or Co9Fe3Bi1Mo12O51. 1-Butene-TPD and 2-butene-TPD measurements revealed that ZnFe2O4 catalyst retained more selective oxygen species for the reaction with 2-butene than for the reaction with 1-butene, while Co9Fe3Bi1Mo12O51 catalyst retained more selective oxygen species for the reaction with 1-butene than for the reaction with 2-butene. The synergistic effect of ZnFe2O4 (first-bed) and Co9Fe3Bi1Mo12O51 (second-bed) catalysts in the oxidative dehydrogenation of C4 raffinate-3 was attributed to the combination of high catalytic activity of ZnFe2O4 for 2-butene and high catalytic activity of Co9Fe3Bi1Mo12O51 for 1-butene. [ABSTRACT FROM AUTHOR]

Zinc ferrite (ZnFe2O4) catalysts were prepared by a co-precipitation method using aqueous buffer solution with different pH (pH = 6−12), and applied to the oxidative dehydrogenation of n-butene to 1,3-butadiene. Conversion of n-butene and yield for 1,3-butadiene showed volcano-shaped curves with respect to pH value employed during the co-precipitation step. NH3-TPD experiments were conducted to correlate the acid property with the catalytic performance of zinc ferrite catalysts. It was revealed that the catalytic performance of zinc ferrite catalysts in the oxidative dehydrogenation of n-butene was closely related to the surface acidity of the catalysts. Conversion of n-butene and yield for 1,3-butadiene increased with increasing surface acidity of the catalysts. Among the catalysts tested, the zinc ferrite catalyst prepared at pH = 8 showed the best catalytic performance in the oxidative dehydrogenation of n-butene, which was attributed to its largest surface acidity. [ABSTRACT FROM AUTHOR]