To elucidate the thermal transport mechanisms at interfaces in micro- and nanoscale electronic devices, real-time monitoring of temperature variations at the microscopic and nanoscopic levels is crucial. Micro-nano fiber Bragg grating (FBG) sensors have been demonstrated as effective in-situ optical temperature probes for measuring local temperatures. Time-stretch dispersion Fourier transform (TS-DFT) that enables fast, continuous, single-shot measurements in optical sensing has been integrated with a micro-nano FBG probe (FBG) for local temperature sensing.
View Article and Find Full Text PDFExploiting cellulose-derived levulinic acid (LA) in biorefinery has potential application prospects, and the development of efficient and stable catalysts is crucial yet challenging. In this study, a bimetallic synergy strategy was proposed to construct an efficient and durable solid acid catalyst with crystalline solid solution by a totally solid-phase method. Mechanical activation (MA)-treated precursor (metal salts, starch, and urea) was calcined to obtain a stable biomass-derived carbon (BC)-supported AlZr (MA-AZ/BC) composite, which was applied for catalytic conversion of cellulose to LA in aqueous-phase system.
View Article and Find Full Text PDFThis study aimed to produce bio-based levulinic acid (LA) via direct and efficient conversion of cellulose catalyzed by a sustainable solid acid. A carbon foam (CF)-supported aluminotungstic acid (HAlW/CF) catalyst with Brønsted-Lewis dual-acidic sites was creatively engineered by a hydrothermal impregnation method. The activity of the HAlW/CF catalyst was determined via the hydrolysis and conversion of cellulose to prepare LA in aqueous system.
View Article and Find Full Text PDFThe development of sustainable catalysts for the efficient conversion of biomass to desirable chemicals is significant and challenging. Herein, a stable biochar (BC)-supported amorphous aluminum solid acid catalyst with Brønsted-Lewis dual acid sites was constructed through one-step calcination of a mechanical activation (MA)-treated precursor (starch, urea, and Al(NO)). The as-prepared N-doped BC (N-BC)-supported Al composite (MA-Al/N-BC) was used for the selective catalytic conversion of cellulose to produce levulinic acid (LA).
View Article and Find Full Text PDFThe research objective of this investigation is to explore the influence of filtrate reducer and reservoir characteristics on the filtration reduction of drilling fluid during the drilling process, and the filtration reduction mechanism of drilling fluids is also revealed. The results obtained that a synthetic filtrate reducer can significantly reduce the filtration coefficient than that of the commercial filtrate reducer. Moreover, the filtration coefficient of drilling fluid constructed from synthetic filtrate reducer is reduced from 4.
View Article and Find Full Text PDFGuar fracturing technology has been considered as a kind of popular EOR technology, but the weak static suspension capacity becomes a challenge due to the poor temperature resistance and stability of guar fracturing fluid. The main goal of this investigation is to explore the effect of different factors on the high-pressure static sand suspension of guar gum fracturing fluid by a synthetic efficient nano-ZrO cross-linker. In particular, a mechanism of static suspended sand of nano-ZrO cross-linker is analyzed by microscopic simulation.
View Article and Find Full Text PDFBackground: Leaf color is an important ornamental trait of colored-leaf plants. The change of leaf color is closely related to the synthesis and accumulation of anthocyanins in leaves. Acer pseudosieboldianum is a colored-leaf tree native to Northeastern China, however, there was less knowledge in Acer about anthocyanins biosynthesis and many steps of the pathway remain unknown to date.
View Article and Find Full Text PDFHigh-refractive-index nanoparticles (NPs), such as silicon NPs, were considered as effective carriers in their response to a magnetic field at optical frequencies. Such NPs play an important role in many state-of-the-art technologies in nano-optics. Although the resonance properties of these NPs when varying their structural parameters have been studied intensely in the past few years, their interaction with the underlying substrate has seldom been discussed, in particular, when the substrate is a waveguide structure that significantly modulates the optical responses of the NPs.
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