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Kinetics of the reaction of OH radical with ethylfluoroacetate,ethyl 4,4,4-trifluorobutyrate,and butylfluoroacetate

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Journal of Environmental Sciences 2025年第5期151卷 273-283页

作者： Pedro L.Lugo Vianni Straccia Mariano A.Teruel María B.Blanco Laboratorio Universitario de Química y Contaminación del Aire(L.U.Q.C.A) Institute for Research in Physical Chemistry of Córdoba(I.N.F.I.Q.C.)Department of Physical ChemistryFaculty of Chemical SciencesNational University of CórdobaUniversity CityCórdoba 5000Argentina Institute for Atmospheric and Environmental Research University of WuppertalWuppertal DE-42097Germany

Kinetics of the gas-phase reactions of•OH radicals with a series of fluoroesters were studied for the first time at 298±3 K and atmospheric *** rate coefficients were determined by in situ FTIR spectroscopy in nitrogen and GC-FID in air to monitor the decay of reactants and *** following coefficient values(in 10^(−12)cm^(3)/(molecule•sec))were obtained for ethyl fluoroacetate(EFA),ethyl 4,4,4-trifluorobutyrate(ETB),and butyl fluoroacetate(BFA),respectively:k_(1)(EFA+OH)=1.15±0.25 by FTIR and 1.34±0.23 by GC-FID;k_(2)(ETB+OH)=1.61±0.36 by FTIR and 2.02±0.30 by GC-FID;k_(3)(BFA+OH)=2.24±0.37 by *** trends were developed and correlated with the number of CH_(3)and F substituents in the fluoroester,and structure-activity relationships(SARs)calculations were *** addition,the tropospheric lifetimes of EFA,ETB,and BFA upon degradation by OH radicals were calculated to be 9,6,and 5 days,respectively,indicating that these fluorinated compounds could have a possible regional effect from the emission *** small photochemical ozone creation potentials of 9,7,and 19 were estimated for EFA,ETB,and BFA,*** GlobalWarming Potentials(GWPs)for EFA,ETB,and BFA were calculated for different time *** a 20-year time horizon,the GWPs were 1.393,0.063,and 0.062,*** the case of a 100-year time horizon,the GWPs were 0.379,0.017,and 0.017,and for a 500-year time horizon,the GWPs were 0.108,0.005,and 0.005 for EFA,ETB,and BFA.

关键词： CFC replacements sinks in situ FTIR SAR Acidification potentials Greenhouse gases

PHOTOVISCOELASTICITY—AN EXPERIMENTAL METHOD IN VISCOELASTIC STRESS ANALYSIS

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Applied Mathematics and Mechanics(English Edition) 1987年第11期8卷 1019-1026页

作者： Karl-Hans Laermann bergische universitat-Gesamthochschule wuppertal West Germany

In this paper,the photoviscoelasticity method of viscoelastic stress analysis has beendiscussed in *** is shown that,in order to avoid the effects of shrinkage andaging in thetest specimens,it is suggested that the specimens should be tempered for three days at atemperature of 60℃ before starting the experiments,and the temperature filteringarrangement is recommended in the experimental setups to keep the temperature *** the axi-symmetrical time-dependent stress state,the determination of theprinciple axes of the refraction tensor experimentally remains an unsufficiently *** avoid dynamic effect in the step wise loading,the time of measurement in everystep should be limited in about one secend.

关键词： AN EXPERIMENTAL METHOD IN VISCOELASTIC STRESS ANALYSIS PHOTOVISCOELASTICITY

Olfactory receptors in neural regeneration in the central nervous system

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Neural Regeneration Research 2025年第9期20卷 2480-2494页

作者： Rafael Franco Claudia Garrigós Toni Capó Joan Serrano-Marín Rafael Rivas-Santisteban Jaume Lillo Molecular Neurobiology Laboratory Department of Biochemistry and Molecular BiomedicineFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain CiberNed Network Center for Biomedical Research in Neurodegenerative Diseases Spanish National Health Institute Carlos ⅢMadridSpain School of Chemistry Universitat de BarcelonaBarcelonaSpain Department of Biochemistry and Physiology School of Pharmacy and Food SciencesUniversitat de BarcelonaBarcelonaSpain Laboratory of Computational Medicine Biostatistics UnitFaculty of MedicineAutonomous University of BarcelonaCampus BellaterraBarcelonaSpain

Olfactory receptors are crucial for detecting odors and play a vital role in our sense of smell,influencing behaviors from food choices to emotional *** receptors also contribute to our perception of flavor and have potential applications in medical diagnostics and environmental *** ability of the olfactory system to regenerate its sensory neurons provides a unique model to study neural regeneration,a phenomenon largely absent in the central nervous *** gained from how olfactory neurons continuously replace themselves and reestablish functional connections can provide strategies to promote similar regenerative processes in the central nervous system,where damage often results in permanent *** the molecular and cellular mechanisms underpinning olfactory neuron regeneration could pave the way for developing therapeutic approaches to treat spinal co rd injuries and neurodegenerative diseases like Alzheimer's *** ctory receptors are found in almost any cell of eve ry orga n/tissue of the mammalian *** ectopic expression provides insights into the chemical structures that can activate olfactory *** addition to odors,olfactory receptors in ectopic expression may respond to endogenous compounds and molecules produced by mucosal colonizing *** analysis of the function of olfactory receptors in ectopic expression provides valuable information on the signaling pathway engaged upon receptor activation and the receptor's role in proliferation and cell differentiation *** review explo res the ectopic expression of olfa ctory receptors and the role they may play in neural regeneration within the central nervous system,with particular attention to compounds that can activate these receptors to initiate regenerative *** suggests that olfactory receptors could serve as potential therapeutic targets for enhancing neural repair and recovery following central nervous syste

关键词： adenosine receptors adrenergic receptors ectopic expression G proteincoupled receptors glia neurons

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Atmospheric chemistry of trifluorodicarbonyls initiated by Cl atoms:Reactivity trends,mechanism,and acid formation yields

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Journal of Environmental Sciences 2025年第5期151卷 12-25页

作者： Pedro L.Lugo Vianni G.Straccia Cynthia B.Rivela Mariano A.Teruel María B.Blanco Laboratorio Universitario de Química y Contaminación del Aire(L.U.Q.C.A) Instituto de Investigaciones en Fisicoquímica de Córdoba(I.N.F.I.Q.C.)Dpto.de Fisicoquímica.Facultad de Ciencias QuímicasUniversidad Nacional de Córdoba.Ciudad Universitaria5000 CórdobaArgentina Institute for Atmospheric and Environmental Research University of WuppertalDE-42097 WuppertalGermany

Rate coefficients of the gas-phase reactions of Cl atoms with a series of fluorinated diketones(FDKs):CF_(3)C(O)CH_(2)C(O)CH_(3)(TFP),CF_(3)C(O)CH_(2)C(O)CH_(2)CH_(3)(TFH)and CF_(3)C(O)CH_(2)C(O)CH(CH_(3))2(TFMH),have been measured at(298±2)K and under atmospheric *** experiments were performed using the relative-rate method with a GC-FID detection *** different determinations and references used,the following rate coefficients were obtained(in cm3/(molecule·sec)):k_(4)(TFP+Cl)=(1.75±0.21)×10^(−10),k_(5)(TFH+Cl)=(2.05±0.23)×10^(−10),k_(6)(TFMH+Cl)=(2.71±0.34)×10^(−10).Reactivity trends of FDKs were discussed and Free Energy Relationships analysis was *** expression lgkOH=1.68 lgkCl+5.71 was obtained for the reactivity of the studied FDKs together with similar unsaturated VOCs with Cl and OH radicals Additionally,acetic acid(CH_(3)C(O)OH)and trifluoroacetic acid(CF_(3)C(O)OH)were positively identified and quantified as degradation products using in situ FTIR *** to the identified products,atmospheric chemical mechanisms were *** atmospheric implications of the studied reactions were assessed by the estimation of the tropospheric lifetimes of TFP,TFH,and TFMH concerning their reaction with Cl atoms to be 48,41,and 31 hours,*** relatively short residence in the atmosphere of the fluorocarbons studied will have a local/regional impact with restricted *** warming potential(GWP(20 yr))calculated for the studied fluoro diketones were 0.014,0.003 and 0.001 for TFP,TFH and TFMH,respectively with a negligible contribution to the greenhouse effect.

关键词： Fluorinated diketones Kinetics SPME-GC-FID FTIR in situ SAR Free energy relationships

Tetraphenylethylene-BODIPY aggregation-induced emission luminogens for near-infrared polymer light-emitting diodes

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Science China Chemistry 2018年第8期61卷 932-939页

作者： Sebnem Baysec Alessandro Minotto Patrick Klein Simone Poddi Andrea Zampetti Sybille Allard Franco Cacialli Ullrich Scherf Macromolecular Chemistry and Institute for Polymer Technology Bergische Universitat Wuppertal Wuppertal 42097 Germany Department of Physics and Astronomy and London Centre for Nanotechnology University College London London WCIE 6BT UK

The aggregation-induced emission(AIE) phenomenon provides a new direction for the development of organic light-emitting devices. Here, we present a new class of emitters based on 4,4-difluoro-4-bora-3 a,4 a-diaza-s-indacene(BODIPY), functionalized at different positions with tetraphenylethylene(TPE), which is one of the most famous AIE luminogens. Thanks to this modification, we were able to tune the photoluminescence of the BODIPY moiety from the green to the near-infrared(NIR)spectral range and achieve PL efficiencies of ~50% in the solid state. Remarkably, we observed an enhancement of the AIE and up to ~100% photoluminescence efficiencies by blending the TPE-substituted BODIPY fluorophores with a poly[(9,9-di-noctylfluorene-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,7-diyl)](F8 BT) matrix. By incorporating these blends in organic lightemitting diodes(OLEDs), we obtained electroluminescence peaked in the range 650–700 nm with up to 1.8% external quantum efficiency and ~2 m W/cm2 radiance, a remarkable result for red/NIR emitting and solution-processed OLEDs.

关键词： BODIPY organic light-emitting diode aggregation-induced emission NIR emission photoluminescence electro luminescence

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A New Convergent Explicit Tree-Grid Method for HJB Equations in One Space Dimension

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Numerical Mathematics(Theory,Methods and Applications) 2018年第1期11卷 1-29页

作者： Igor Kossaczky Matthias Ehrhardt Michael Gunther Lehrstuhl fur Angewandte Mathematik und Numerische Analysis Fakultat fur Mathematik und NaturwissenschaftenBergische Universitat WuppertalGaußstrasse 2042119 WuppertalGermany

In this work we introduce a new unconditionally convergent explicit Tree-Grid Method for solving stochastic control problems with one space and one time dimension or equivalently,the corresponding Hamilton-Jacobi-Bellman *** prove the convergence of the method and outline the relationships to other numerical *** case of vanishing diffusion is treated by introducing an artificial diffusion *** illustrate the superiority of our method to the standardly used implicit finite difference method on two numerical examples from finance.

关键词： Tree-Grid Method Hamilton-Jacobi-Bellman equation Stochastic control problem

Cloning and Characterization of Genes Encoded in dTDP-D-mycaminose Biosynthetic Pathway from a Midecamycin-producing Strain,Streptomyces mycarofaciens

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Acta Biochimica et Biophysica Sinica 2007年第3期39卷 187-193页

作者： Wolfgang PIEPERSBERG Institute of Chemical Microbiology bergische University D-42097 wuppertal Germany

Two subclusters from Streptomyces mycarofaciens,a midecamycin producer,were clonedand partially *** region was located at the 5’ end of the mid polyketide synthase(PKS)genesand contained the genes midA,midB and *** other region was at the 3’ end of the PKS genes andcontained midK,midI and *** of the nucleotide sequence revealed that these genes encodedTDP-glucose synthase(midA),dTDP-glucose dehydratase(midB),aminotransferase(midC),methyltransferase(midK),glycosyltransferase(midI)and an assistant gene(midH).All of these genes areinvolved in the biosynthesis of dTDP-D-mycaminose,the first deoxysugar of midecamycin,and intransferring the mycaminose to the midecamycin aglycone in *** to gene pairsdes Ⅷ/desⅦ in *** and tylMⅢ/tylMⅡ in ***,the product of midH probablyfunctions as an auxiliary protein required by the MidI protein for efficient glycosyltransfer in midecamycinbiosynthesis.

关键词： deoxysugar dTDP-D-mycaminose midecamycin Streptomyces mycarofaciens

Catalyst-and solvent-free,thermal generation of microporous polymer networks

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Science China Chemistry 2017年第8期60卷 1103-1106页

作者： christian widling michael forster venkata m.suresh ullrich scherf bergische Universitdt wuppertal Macromolecular Chemistry Group （buwmakro） and Institute for Polymer Technology D-42119 Wuppertal Germany

Multifunctional iodoaryl monomers were used for the catalyst- and solvent-free generation of microporous polymer networks of high surface areas up to 732mEg-1. The thermal conversion of the monomers relies on the homolytic cleavage of weak iodine-carbon bonds followed by a C-C coupling of the radicalic intermediates. By using tri- or tetrafunctional monomers and by tuning reaction temperature and time, the optimum reaction conditions allow the formation of the corresponding microporous networks in good yields of 71%-86%. The resulting networks exhibit notable high CO2 and H2 adsorption capacities of up to 8.89 wt% （273K, 1 bar） and up to 1.31 wt% （77K, 1 bar）, respectively.

关键词： microporous polymer networks thermal generation gas uptake

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An ADI Sparse Grid method for Pricing Efficiently American Options under the Heston Model

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Advances in Applied Mathematics and Mechanics 2021年第6期13卷 1384-1397页

作者： A.Clevenhaus M.Ehrhardt M.Gunther Institute of Mathematical Modelling Analysis and Computational Mathematics(IMACM)Chair of Applied Mathematics and Numerical AnalysisBergische Universitat WuppertalGaußstraße 2042119 WuppertalGermany

One goal of financial research is to determine fair prices on the financial *** financial models and the data sets on which they are based are becoming ever larger and thus more complex,financial instruments must be further developed to adapt to the new complexity,with short runtimes and efficient use of memory *** we show the effects of combining known strategies and incorporating new ideas to further improve numerical techniques in computational *** this paper we combine an ADI(alternating direction implicit)scheme for the temporal discretization with a sparse grid approach and the combination *** later approach considerably reduces the number of“spatial”grid *** presented standard financial problem for the valuation of American options using the Heston model is chosen to illustrate the advantages of our approach,since it can easily be adapted to other more complex models.

关键词： Sparse grid combination technique American options ADI Heston model