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Article
Synthesis of cyclopropylamine with phase transfer catalysis
Cyclopropylamine is synthesized with γ-butyrolactone and isopropanol by five steps of ring-opening esterification, cyclization, hydrolysis, acylation and Hofmann degradation. Cyclization and hydrolysis are key...
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Article
Synthesis and structural characterization of urea–isobutyraldehyde–formaldehyde resins
Urea–isobutyraldehyde–formaldehyde (UIF) resins were synthesized using urea, isobutyraldehyde, and formaldehyde; sulfuric acid was used as a catalyst. The effects of molar ratio of urea/isobutyraldehyde/formal...
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Chapter and Conference Paper
Image Enhancement Based on NSCT
An algorithm for image enhancement based on nonsubsampled contourlet transform (NSCT) is proposed. NSCT is multiresolutional, localized, multidirectional and anisotropic so it can more effectively capture high...
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Article
Open AccessDimensional hierarchy of higher-order topology in three-dimensional sonic crystals
Wave trap** and manipulation are at the heart of modern integrated photonics and acoustics. Grand challenges emerge on increasing the integration density and reducing the wave leakage/noises due to fabricati...
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Article
Open AccessQuantum superposition demonstrated higher-order topological bound states in the continuum
Higher-order topological insulators, as newly found non-trivial materials and structures, possess topological phases beyond the conventional bulk-boundary correspondence. In previous studies, in-gap boundary s...
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Article
Open AccessArtifact reduction in lenslet array near-eye displays
Lenslet array near-eye displays are a revolutionary technology that generates a virtual image in the field of view of the observer. Although this technology is advantageous in creating compact near-eye display...
