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1.
Dapeng Liu Binod R. Giri Milán Szőri Béla Viskolcz Et-touhami Es-sebbar Aamir Farooq 《Proceedings of the Combustion Institute》2021,38(1):967-976
NOx mitigation is a central focus of combustion technologies with increasingly stringent emission regulations. NOx can also enhance the autoignition of hydrocarbon fuels and can promote soot oxidation. The reaction between allyl radical (C3H5) and NOx plays an important role in the oxidation kinetics of propene. In this work, we measured the absolute rate coefficients for the redox reaction between C3H5 and NOx over the temperature range of 1000–1252 K and pressure range of 1.5–5.0 bar using a shock tube and UV laser absorption technique. We produced C3H5 by shock heating of C3H5I behind reflected shock waves. Using a Ti:Sapphire laser system with frequency quadrupling, we monitored the kinetics of C3H5 at 220 nm. Unlike low-temperature chemistry, the two target reactions, C3H5 + NO → products (R1) and C3H5 + NO2 → products (R2), exhibited a strong positive temperature dependence for this radical-radical type reaction. However, these reactions did not show any pressure dependence over the pressure range of 1.5–5.0 bar, indicating that the measured rate coefficients are close to the high-pressure limit. The measured values of the rate coefficients resulted in the following Arrhenius expressions (in unit of cm3/molecule/s):To our knowledge, these are the first high-temperature measurements of allyl + NOx reactions. The reported data will be highly useful in understanding the interaction of NOx with resonantly stabilized radicals as well as the mutual sensitization effect of NOx on hydrocarbon fuels. 相似文献
2.
Synthesis,Electronic Properties and WOLED Devices of Planar Phosphorus‐Containing Polycyclic Aromatic Hydrocarbons 下载免费PDF全文
Dr. François Riobé Rózsa Szűcs Dr. Pierre‐Antoine Bouit Dr. Denis Tondelier Bernard Geffroy Fátima Aparicio Julia Buendía Prof. Luis Sánchez Prof. Régis Réau Prof. László Nyulászi Prof. Muriel Hissler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6547-6556
We describe the synthesis and the physical properties of polyaromatic hydrocarbons (PAHs) containing a phosphorus atom at the edge. In particular, the impact of the successive addition of aromatic rings on the electronic properties was investigated by experimental (UV/Vis absorption, fluorescence, cyclic voltammetry) and theoretical studies (DFT). The physical properties recorded in solution and in the solid state showed that the P‐containing PAHs exhibit properties expected for an emitter in white organic light‐emitting diodes (WOLEDs). 相似文献
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Order - In this paper, we investigate the class of lattices representable with posets satisfying the DCC condition. We describe a way to decide whether a finite lattice is in this class. We also... 相似文献
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Contrary to the expectation arising from the tanglegram Kuratowski theorem of Czabarka et al. (SIAM J. Discrete Math. 31(3), 1732–1750, 2017), we construct an infinite antichain of planar tanglegrams with respect to the induced subtanglegram partial order. R.E. Tarjan, R. Laver, D.A. Spielman and M. Bóna, and possibly others, showed that the partially ordered set of finite permutations ordered by deletion of entries contains an infinite antichain, i.e., there exists an infinite collection of permutations, such that none of them contains another as a pattern. Our construction adds a twist to the construction of Spielman and Bóna (Electr. J. Comb. 7, N2, 2000).
相似文献8.
Veronika Takács-Kollár Miklós Nyitrai Dénes Lőrinczy Gábor Hild 《Journal of Thermal Analysis and Calorimetry》2017,127(2):1261-1266
Differential scanning calorimetry was applied to compare the effects of mammalian twinfilin-1 or toxofilin on the thermodynamic properties of actin monomer. Although twinfilin and toxofilin have different structure and actin-binding sites, they similarly increased the thermodynamic stability of monomeric actin. The mammalian twinfilin increased, while the toxofilin did not significantly change the T1/2 value (the width at half-height of the transition peak) during the complex formation between the actin and the monomer binding proteins. In case of toxofilin, the EA value (activation energy) significantly increased compared to twinfilin where the activation energy was nearly insensitive to the complex formation. It seems that toxofilin can achieve its main function as an actin monomer sequestering protein by more effectively and consistently modifying the basic thermodynamic properties of the monomeric actin. 相似文献
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D. Lőrinczy 《Journal of Thermal Analysis and Calorimetry》2017,130(3):1263-1280
In this paper, I will sum up our research activity from this field performed in the last about 25 years. I will focus on three main points: basic muscle research in the different intermediate states of ATP hydrolysis cycle during muscle contraction, R&D activities to develop and test different dairy products and TA application in some surgical and diagnostic problem. Our initial research concerned the investigation of thermal stability of main muscle proteins clarifies their basic unfolding characteristics. Later we extended the thermal stability investigation from protein solution to the myosin myofibrils and to the higher organization of muscle proteins, the muscle fibres, checking the effect of nucleotides. At that time, it became possible to stabilize the different intermediate states of ATP hydrolysis up to the time of DSC measurement, using different Pi analogues (Vi, AlFx and BeFx) and non-hydrolysable ATP analogue (AMP.PNP). This way the targets were AM.ADP.Vi (and with AlFx or BeFx) so-called weak binding state, AM.ADP the “strong” binding state as well as the “rigor” AM complex state. AM.AMP.PNP state was used to mimic the AM.ATP state. With our R&D cooperation, a cold spreadable butter was successfully developed. We were a partner in the development of Ca-enriched cheese, in its spreadable form too as well as in the development and testing of different dairy products using probiotic cultures. Our TA activity covers a wide range of medical applications, e.g. investigation of the different abnormalities of human leg skeletal muscle, different stages of degeneration of human vertebral disc, to judge the goodness/applicability of different suture technique on tracheal cartilage in primary airway reconstruction or the characterization of different self-expandable stents implantation in the oesophagus treatment. We have joined those groups who try to use DSC in the diagnosis of different diseases from blood plasma, e.g. in the case of breast cancer, melanoma, in psoriasis. 相似文献
10.
Spatial structures break their symmetry under the influence of shear stress arising from fluid flow. Here, we present surface instabilities appearing on chitosan tubes when an acidic solution of chitosan with various molecular weight is injected into a pool of sodium hydroxide solution. At slow flow rates wrinkle-to-fold transition takes place along the direction of the flow yielding a banded structure. For greater injection rates we observe coexisting modes of wrinkles and folds which are stabilized to periodic wrinkles when the alkaline concentration is increased. The instabilities are characterized by the scaling laws of the pattern wavelength and amplitude with the tube characteristics. Our experimental adaptation of mechanical instabilities provides a new in situ method to create soft biomaterials with the desired surface morphology without the use of any prefabricated templates. 相似文献