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The optimized reaction conditions of selective alkene bromination for gasolines containing aromatics and saturated hydrocarbons are presented. By this way, the interfering problem in alkene determination from coeluting saturated hydrocarbons has been solved. So the detailed hydrocarbon analysis can be improved by a simple system containing polar and non-polar columns or by a gas chromatograph coupled with an atomic emission detector (GC-AED). Under the optimized conditions, it was found that the alkene compounds were selectively and completely brominated but the aromatics and alkane compounds were remained unaffected. A simple treatment, 90 s-120 s for reaction and 10 s-20 s for removing the excess bromine, can be easily realized. The treatment is applied for the different types of gasoline containing 0-100% alkene. Besides, one of the most important applications of this treatment is to analyse the hydrocarbons in detail from the fluid catalytic cracking (FCC) gasoline. The samples in these cases may not be accurately analyzed when using the traditional method of hydrocarbon analysis because of the presence of coeluted interfering olefins above C7.
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Med Eng Phys
October 2025
Ansys Inc., Houston, TX 77094, USA.
Introduction: Benchtop and animal models have traditionally been used to study the propagation of Onyx Liquid Embolic Systems (Onyx) used in the treatment of brain arteriovenous malformations (AVM). However, such models are costly, do not provide sufficient detail to elucidate how variations in Onyx viscosity alter flow dynamics, and rely on some trial-and-error, resulting in elongated timelines for product development.
Objectives: The goal of this study was to leverage Computational Fluid Dynamics (CFD) simulations to predict the behavior of different Onyx formulations.
Turk J Pediatr
September 2025
Department of Child and Adolescent Psychiatry, Ankara Bilkent City Hospital, Faculty of Medicine, Ankara Yıldırım Beyazıt University, Ankara, Türkiye.
Background: Intractable paroxysmal sneezing is a rare and diagnostically challenging condition in children, often mimicking organic diseases. While it is often addressed as psychogenic in the literature, our case presented findings suggestive of a tic disorder, highlighting the need for a broader diagnostic perspective.
Case Presentation: An 11-year-old girl was referred to the child and adolescent psychiatry clinic with a one-year history of persistent and fluctuating sneezing episodes.
PLoS One
September 2025
Plateforme de Biopharmacie, Université de Montréal, Montréal, Quebec, Canada.
Introduction: The Covid-19 pandemic has intensified shortages in various pharmaceutical products, notably injectable propofol in lipid emulsion form. Its demand surged sharply due to its critical role in intubating patients with respiratory distress during the pandemic, exposing vulnerabilities in the supply chain for this essential product.
Objectives: This project aims to develop an alternative formulation to commercially available propofol products and to evaluate its stability through a detailed study.
Angew Chem Int Ed Engl
September 2025
Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Straße 1, 53121, Bonn, Germany.
A diterpene synthase from Chryseobacterium joostei was characterised and produces the five unique compounds chryseojoostenes A-E. Chryseojoostenes D and E were produced in too low amounts for isolation from the wildtype enzyme, but extensive site-directed mutagenesis resulted in an enzyme variant in which the production of these compounds was enhanced. The biosynthesis of the enzyme products was investigated in detail through a combined experimental and computational approach, indicating a complex hydrogen scrambling during terpene cyclisation and a long-range proton shift towards chryseojoostene E.
View Article and Find Full Text PDFJ Chem Phys
September 2025
MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, School of Optoelectronic Science and Engineering, South China Normal Un
Propargyl radical (•C3H3) and butadienyl radical (•i-C4H5) are two crucial intermediates in combustion and astrochemistry, particularly in the formation of C7H8 aromatics such as toluene. However, the precise formation mechanisms of the first-ring aromatics through C3 + C4 reactions have remained ambiguous. This study explores the detailed potential energy surface (PES) of C7H8 at the •C3H3 + •i-C4H5 entrance reaction channel, alongside conducting kinetic calculations and modeling.
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