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991.
Li Zhou Minjie Zhao Ali Khalil Christophe Marcic Françoise Bindler Eric Marchioni 《Analytical and bioanalytical chemistry》2013,405(28):9125-9137
Headspace solid-phase microextraction (HS-SPME) followed by gas chromatography–mass spectrometry analysis (GC-MS) was used to investigate the volatile compounds from oxidised phosphatidylcholine molecular species. 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine (SOPC) and 1-stearoyl-2-linoleoyl-sn-glycero-3-phosphocholine (SLPC) were chosen as models. The influence of several parameters on the efficiency of volatile oxidised compounds (VOCs) microextraction, such as type of fibre, extraction duration and temperature were studied. The best results were obtained with a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibre used at 50 °C during 25 min. The effect of oxidation temperature on the yield of VOCs from SOPC and SLPC was investigated. Oxidative kinetics of SOPC and SLPC were investigated by measuring both the production of VOCs and the degradation of starting materials. More than 30 VOCs were detected by means of the reference mass spectra of the National Institute of Standards and Technology mass spectral library, and most of them were further confirmed by comparing their mass spectra and retention time with those obtained from authentic reference compounds under the same analytical conditions. Moreover, the origins of VOCs from oxidised PLs were studied by comparing those obtained from their corresponding triacylglycerides under the same experimental conditions. The main VOCs identified from oxidised SOPC were (E)-2-decenal, nonanal and octanal and from oxidised SLPC were (E)-2-heptenal, (E)-2-octenal and (E, E)-2,4-decadienal. The proposed method was applied to a real food sample, soy lecithin. Figure
Production of volatiles from oxidised phospholipid 相似文献
992.
Bardis Konstantinos Kyrtatos Panagiotis Barro Christophe Denisov Alexey Wright Yuri Martin Herrmann Kai Boulouchos Konstantinos 《Flow, Turbulence and Combustion》2021,107(2):307-342
Flow, Turbulence and Combustion - Turbulent jet ignition (TJI) is a promising combustion technology for burning highly diluted air-fuel mixtures. Computationally efficient models to assess the... 相似文献
993.
Bessem Ben Doudou Jun Chen Alexandre Vivet Christophe Poîlane M’hamed Ayachi 《Physica E: Low-dimensional Systems and Nanostructures》2011,44(1):120-123
Using first-principle calculations, we have investigated the chemical functionalization of (8,0) zigzag single wall carbon nanotubes (SWNTs) by the amine group on Stone–Wales (SW) defects. The binding of NH2 with the defective (8,0) nanotube was explored and the preferential grafting sites have been identified. On the other hand, the modifications induced by SW defect and functional groups in the structural and electronic properties of (8,0) SWNT have also been investigated. The role of SW defects in the chemical reactivity of carbon nanotubes was well identified. 相似文献
994.
Lutfi RA Liu CJ Stoelinga CN 《The Journal of the Acoustical Society of America》2011,129(4):2104-2111
The auditory discrimination of force of impact was measured for three groups of listeners using sounds synthesized according to first-order equations of motion for the homogenous, isotropic bar [Morse and Ingard (1968). Theoretical Acoustics pp. 175-191]. The three groups were professional percussionists, nonmusicians, and individuals recruited from the general population without regard to musical background. In the two-interval, forced-choice procedure, listeners chose the sound corresponding to the greater force of impact as the length of the bar varied from one presentation to the next. From the equations of motion, a maximum-likelihood test for the task was determined to be of the form Δlog A + αΔ log f > 0, where A and f are the amplitude and frequency of any one partial and α = 0.5. Relative decision weights on Δ log f were obtained from the trial-by-trial responses of listeners and compared to α. Percussionists generally outperformed the other groups; however, the obtained decision weights of all listeners deviated significantly from α and showed variability within groups far in excess of the variability associated with replication. Providing correct feedback after each trial had little effect on the decision weights. The variability in these measures was comparable to that seen in studies involving the auditory discrimination of other source attributes. 相似文献
995.
We investigate the dynamical charge response of the Anderson model viewed as a quantum RC circuit. Applying a low-energy effective Fermi liquid theory, a generalized Korringa-Shiba formula is derived at zero temperature, and the charge relaxation resistance is expressed solely in terms of static susceptibilities which are accessible by Bethe ansatz. We identify a giant charge relaxation resistance at intermediate magnetic fields related to the destruction of the Kondo singlet. The scaling properties of this peak are computed analytically in the Kondo regime. We also show that the resistance peak fades away at the particle-hole symmetric point. 相似文献
996.
Spectral compression by self-phase modulation of amplitude- and phase-shaped pulses is demonstrated as superior compared to pulses that have only been phase shaped. We synthesize linearly negatively chirped parabolic pulses, which we send through a nonlinear photonic crystal fiber, in which self-phase modulation compresses the spectrum of the pulses to within 20% of the Fourier transform limit. 相似文献
997.
Xu J Ding Y Peucheret C Seoane J Mulvad HC Galili M Xue W Mørk J Jeppesen P 《Optics letters》2011,36(9):1560-1562
We propose and demonstrate the use of a single semiconductor optical amplifier (SOA) and optical filtering to time demultiplex tributaries from an optical time division multiplexing-differential phase shift keying (OTDM-DPSK) signal. The scheme takes advantage of the fact that phase variations added to the target channel by cross-phase modulation from the control signal are effectively subtracted in the differential demodulation scheme employed for DPSK signals. Demultiplexing from 80 to 40 Gbit/s is demonstrated with moderate power penalty using an SOA with recovery time twice as long as the bit period at 80 Gbit/s. Large dynamic ranges for the input power and SOA current are experimentally demonstrated. The scheme is expected to be scalable toward higher bit rates. 相似文献
998.
Boess E Sureshkumar D Sud A Wirtz C Farès C Klussmann M 《Journal of the American Chemical Society》2011,133(21):8106-8109
The mechanism of an aerobic copper-catalyzed oxidative coupling reaction with N-phenyl tetrahydroisoquinoline was investigated. The oxidized species formed from the reaction of the amine with the copper catalyst were analyzed by NMR-spectroscopy. An iminium dichlorocuprate was found to be the reactive intermediate and could be structurally characterized by X-ray crystallography. The effect of methanol to effectively stabilize the iminium ion was investigated and shown to be beneficial in an oxidative allylation reaction. 相似文献
999.
Selloum Djamel Techer Vincent Henni Abdellah Tingry Sophie Cretin Marc Innocent Christophe 《Journal of Solid State Electrochemistry》2020,24(3):623-631
Journal of Solid State Electrochemistry - Biofuel cells are an attractive alternative to conventional fuel cells, because they use biological catalysts. We report in this article the construction... 相似文献
1000.
Robert N. Grass Reinhard Heckel Christophe Dessimoz Wendelin J. Stark 《Angewandte Chemie (International ed. in English)》2020,59(22):8476-8480
Today, we can read human genomes and store digital data robustly in synthetic DNA. Herein, we report a strategy to intertwine these two technologies to enable the secure storage of valuable information in synthetic DNA, protected with personalized keys. We show that genetic short tandem repeats (STRs) contain sufficient entropy to generate strong encryption keys, and that only one technology, DNA sequencing, is required to simultaneously read the key and the data. Using this approach, we experimentally generated 80 bit strong keys from human DNA, and used such a key to encrypt 17 kB of digital information stored in synthetic DNA. Finally, the decrypted information was recovered perfectly from a single massively parallel sequencing run. 相似文献