The rate constants of OH radicals with CFCF=CCl, CFCH=CF, CFCF=CH, CFCH=CH, and (CF)C=CH have been measured over the temperature range 250-430 K. Kinetic measurements have been carried out using flash photolysis and laser photolysis methods combined respectively with laser-induced fluorescence technique. The Arrhenius rate parameters have been determined as k(CFCF=CCl) = (6.50 ± 0.22) × 10∙exp[(200 ± 10)/T], k(CFCH=CF) = (4.85 ± 0.14) × 10∙exp[(120 ± 10)/T], k(CFCF=CH) = (1.54 ± 0.03) × 10∙exp[- (100 ± 10)/T], k(CFCH=CH) = (1.06 ± 0.02) × 10∙exp[(80 ± 10)/T], and k((CF)C=CH) = (8.75 ± 0.23) × 10∙exp[- (20 ± 10)/T] cm molecule s. Infrared absorption spectra of the halogenated alkenes have been measured at room temperature. The atmospheric lifetime, global warming potential, ozone depleting potential, and photochemical ozone creation potential have been estimated. The change in the reactivity of halogenated alkenes by the substitution has been examined by considering the structure containing the atoms or atomic groups attached to the carbons on both sides of the double bond.
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http://dx.doi.org/10.1007/s11356-018-1700-4 | DOI Listing |
Angew Chem Int Ed Engl
January 2025
Beijing Institute of Technology, School of Chemistry and Chemical Engineering, CHINA.
Carbene-metal-amide (CMA) complexes have diverse applications in luminescence, imaging and sensing. In this study, we designed and synthesized a series of CMA complexes, which were subsequently doped into a PMMA host. These materials demonstrate light-induced dynamic phosphorescence, attributed to their long intrinsic triplet state lifetime (τP,int, in the μs-ms scale), high intersystem crossing (ISC) rate constant (kISC, up to 107 s-1), and bright phosphorescence.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
College of Materials Science and Engineering, Guilin University of Technology, Guilin 541004, China.
This study is the first to convert two waste materials, waste rice noodles (WRN) and red mud (RM), into a low-cost, high-value magnetic photocatalytic composite. WRN was processed via a hydrothermal method to produce a solution containing carbon quantum dots (CQDs). Simultaneously, RM was dissolved in acid to form a Fe ion-rich solution, which was subsequently mixed with the CQDs solution and underwent hydrothermal treatment.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
Unidad Departamental de Química Analítica, Departamento de Química, Facultad de Ciencias, Universidad de La Laguna, Avda. Astrofísico Fco. Sánchez, s/n, 38206 La Laguna, Spain.
Arsenic contamination of water endangers the health of millions of people worldwide, affecting certain countries and regions with especial severity. Interest in the use of Fe-based metal organic frameworks (MOFs) to remove inorganic arsenic species has increased due to their stability and adsorptive properties. In this study, the performance of a synthesized Nano-{Fe-BTC} MOF, containing iron oxide octahedral chains connected by trimesic acid linkers, in adsorbing As(III) and As(V) species was investigated and compared with commercial BasoliteF300 MOF.
View Article and Find Full Text PDFBiopolymers
January 2025
School of Pharmacy and Bioengineering, Keele University, Keele, UK.
Cryogels were fabricated by combining polyvinyl alcohol (PVA) and chitosan of varying molecular weights (Mw). In this study, the effects of chitosan Mw, types of boron-containing molecules on network formation, and boron release rate in resulted cryogels were investigated. The PVA/chitosan blend maintained a constant 4.
View Article and Find Full Text PDFAm J Sports Med
January 2025
Service de chirurgie orthopédique et traumatologique, CHU de Toulouse, France.
Background: The surgical management of bursal-sided partial-thickness rotator cuff tendon tears is controversial. The 2 methods used are in situ repair (ISR), preserving the contingent of intact articular tendon fiber, or tear completion before repair (TCBR) according to the operating surgeon's usual technique. No study with sufficient power has demonstrated a superior technique.
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