By a simple sequent process of dry-gel steam-assisted crystallization and following a top-down alkali-etching treatment, hierarchically structured TS-1 nanozeolites (nanoTS-1_D) with abundant micro/mesopores have been synthesized for the first time, and they exhibit remarkably high specific surface area of 606 m g and pore volume of 0.86 cm g. Characterization by XRD, FTIR, UV-vis and EM confirm the exclusive incorporation of titanium species in zeolite frameworks. More importantly, compared with the microporous TS-1 nanocrystal material with identical particle sizes of 80 nm (nanoTS-1) and submicrometer-sized mesoporous TS-1 material (mesoTS-1), here the reported nanoTS-1_D catalyst shows greatly improved performance in the model reaction of 1-hexene epoxidation. 40.9% olefin conversion and 96.3% epoxide selectivity are achieved and its high stability is verified by the 6 recycling-regeneration tests.
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http://dx.doi.org/10.1039/c9ra00124g | DOI Listing |
Phys Rev Lett
December 2024
University of Oregon, Department of Physics and Materials Science Institute, Eugene, Oregon 97403, USA.
We consider many-particle diffusion in one spatial dimension modeled as "random walks in a random environment." A shared short-range space-time random environment determines the jump distributions that drive the motion of the particles. We determine universal power laws for the environment's contribution to the variance of the extreme first passage time and extreme location.
View Article and Find Full Text PDFMikrochim Acta
January 2025
Key Laboratory of New Energy & New Functional Materials, Shaanxi Key Laboratory of Chemical Reaction Engineering, College of Chemistry and Chemical Engineering, School of Medicine, Yan'an University, Yan'an, Shaanxi, 716000, People's Republic of China.
Dexamethasone sodium phosphate (DSP) and betamethasone sodium phosphate (BSP) imprinted hydrogels embedded with two-dimensional photonic crystals (2DPC) were developed as hormones-sensitive photonic hydrogel sensors with highly sensitive, selective, anti-interference and reproducible recognition capability. The DSP/BSP molecularly imprinted photonic hydrogels (denoted as DSP-MIPH and BSP-MIPH) can specifically recognize DSP/BSP by rebinding the DSP/BET molecules to nanocavities in the hydrogel network. This recognition is enabled by the similar shape, size, and binding sites of the nanocavities to the target molecules.
View Article and Find Full Text PDFOtol Neurotol
January 2025
Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland.
Objective: We aimed to investigate the effect of adding "rapid decelerations" and "vibrations" during a SemontPLUS maneuver on the dynamics of the inner ear and the success rate of canalolithiasis repositioning.
Methods: We used a previously described upscaled (5×) in vitro model of the posterior semicircular canal of the inner ear to analyze the trajectory of a single and clumped surrogate otolith particle (metallic sphere) during a SemontPLUS maneuver (-60 degrees below earth horizontal) on a repositioning chair (TRV). We compared the angular displacement of these particles with and without the application of "vibrations" or "rapid decelerations" using TRV.
Bioconjug Chem
January 2025
Department of Physics, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
Silica nano/microparticles have generated significant interest for the past decades, emerging as a versatile material with a wide range of applications in photonic crystals, bioimaging, chemical sensors, and catalysis. This study focused on synthesizing silica nano/microparticles ranging from 20 nm to 1.2 μm using the Stöber and modified Stöber methods.
View Article and Find Full Text PDFTher Deliv
January 2025
Department of Pharmaceutical Technology, School of Pharmacy, International Medical University (IMU), Kuala Lumpur, Malaysia.
Aim: Abemaciclib (ABE) is an anticancer drug that suffers from low bioavailability and multidrug resistance. This study aims to develop ABE-loaded solid lipid nanoparticles (ABE-SLNs), which will enhance drug solubility and lead to increased cellular uptake and enhanced cytotoxicity when delivering tumor cells.
Methods: Melt emulsification followed by ultrasonication was used as a method of preparation and Quality-by-Design (QbD) was utilized to optimize ABE-SLNs.
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