[1] Airborne formaldehyde (CH2O) measurements were made by tunable diode laser absorption spectroscopy (TDLAS) at high time resolution (1 and 10 s) and precision (±400 and ±120 parts per trillion by volume (pptv) (2s), respectively) during the Texas Air Quality Study (TexAQS) 2000. Measurement accuracy was corroborated by in-flight calibrations and zeros and by overflight comparison with a grou...

The pulsed-field-ionization zero-kinetic-energy photoelectron spectra of the X̃(+2)A(")←X̃(1)A' transition of CH(3)CHCH(2) (propene), CD(3)CDCD(2), and several partially deuterated isotopomers have been recorded in the region of their adiabatic ionization thresholds and up to 2000 cm(-1) of internal energy of the cations. The vibrational structure has been assigned on the basis of the frequency s...

In this paper, we use first principles quantum mechanical methods (B3LYP flavor of Density Functional Theory) to examine the mechanism of selective oxidation and ammoxidation of propene by BiMoOx catalysts. To do this, we use finite clusters chosen to mimic likely sites on the heterogeneous surfaces of the catalysts. We conclude that activation of the propene requires a Bi(V) site, whereas all ...

Propene homopolymers and propene–ethene copolymers with small amount of ethene were synthesized using three catalyst systems [pCH3OPh2C(2,7-diBuFlu)(Cp)]ZrCl2/Me2HNPh][B(C6F5)4] (Cat I), [p-CH3OPh2C(2,7-diBuFlu)(Cp)]ZrCl2/[Ph3C][B(C6F5)4] (Cat II) and [p-CH3OPh2C(2,7-diBuFlu)(Cp)]ZrCl2/MAO (Cat III) in propene bulk phase. The activity of the catalyst was dependent on the formed ion pair: Cat I ...

Kinetic isotopic effects (KIEs) for oxidative dehydrogenation of propane were measured on 10 wt% V2O5/ZrO2. Normal KIEs were obtained using CH3CH2CH3 and CD3CD2CD3 as reactants for primary dehydrogenation (2.8) and combustion (1.9) of propane and for secondary combustion of propene (2.6), suggesting that in all cases C–H bond dissociation is a kinetically relevant step. CH3CH2CH3 and CH3CD2CH3 ...

In this paper we use first principles quantum mechanical methods (B3LYP flavor of density functional theory) to examine the mechanism of selective oxidation and ammoxidation of propene by BiMoOx catalysts. To do this we use finite clusters chosen to mimic likely sites on the heterogeneous surfaces of the catalysts. We conclude that activation of the propene requires a Bi(V) site while all subse...

Sequential multiple methylene (CH2) insertions into adsorbed methyl species on clean gallium-rich GaAs(100)-(4 x 1) occurs to form higher alkenes (ethene, propene, butene) and two higher alkyl iodides (iodoethane, iodopropane), not reported for a semiconductor surface previously.

Two examples are presented for the synthesis of optically active polymers with main-chain chirality from achiral monomers using chiral metal-complexes as catalysts. Asymmetric alternating copolymerization of α-olefins with carbon monoxide provided optically active polyketones when catalyzed by an (R,S)-BINAPHOS–Pd complex. From propene and CO, highly isotactic polyketone with high enantioselect...

Molybdenum oxide nitride (denoted as Mo(O,N)3) was obtained by ammonolysis of α-MoO3 with gaseous ammonia. Electronic and geometric structure, reducibility, and conductivity of Mo(O,N)3 were investigated by XRD, XAS, UV-Vis spectroscopy, and impedance measurements. Catalytic performance in selective propene oxidation was determined by online mass spectrometry und gas chromatography. Upon incorp...

Forests fires are a significant source of chemicals to the atmosphere including numerous non-methane organic compounds (NMOCs). We report airborne measurement of hydrocarbons, acetone and methanol from > 500 whole air samples collected over Eastern Canada, including interceptions of several different boreal biomass burning plumes. From these and concurrent measurements of carbon monoxide (CO) w...