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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
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Emily J. Hopkins Dr. Yurii Prots Dr. Ulrich Burkhardt Dr. Yves Watier Dr. Zhiwei Hu Dr. Chang‐Yang Kuo Dr. Jen‐Che Chiang Dr. Tun‐Wen Pi Dr. Arata Tanaka Prof. Liu Hao Tjeng Dr. Martin Valldor 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7938-7943
Through a solid‐state reaction, a practically phase pure powder of Ba3V2S4O3 was obtained. The crystal structure was confirmed by X‐ray single‐crystal and synchrotron X‐ray powder diffraction (P63, a=10.1620(2), c=5.93212(1) Å). X‐ray absorption spectroscopy, in conjunction with multiplet calculations, clearly describes the vanadium in charge‐disproportionated VIIIS6 and VVSO3 coordinations. The compound is shown to be a strongly correlated Mott insulator, which contradicts previous predictions. Magnetic and specific heat measurements suggest dominant antiferromagnetic spin interactions concomitant with a weak residual ferromagnetic component, and that intrinsic geometric frustration prevents long‐range order from evolving. 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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Lot‐sizing policies for deterioration items under two‐level trade credit with partial trade credit to credit‐risk retailer and limited storage capacity 下载免费PDF全文
Jui‐Jung Liao Kuo‐Nan Huang Kun‐Jen Chung Pin‐Shou Ting Shy‐Der Lin H. M. Srivastava 《Mathematical Methods in the Applied Sciences》2017,40(6):2122-2139
The main purpose of this article is to investigate the optimal wholesaler's replenishment decisions for deterioration items under two levels of the trade credit policy and two storage facilities in order to reflect the supply chain management situation within the economic order quantity framework. In this study, each of the following assumptions have been made: (1) The own warehouse with limited capacity always is not sufficient to store the order quantity, so that a rented warehouse is needed to store the excess units over the capacity of the own warehouse; (2) The wholesaler always obtains the partial trade credit, which is independent of the order quantity offered by the supplier, but the wholesaler offers the full trade credit to the retailer; (3) The wholesaler must take a loan to pay his or her supplier the partial payment immediately when the order is received and then pay off the loan with the entire revenue. Under these three conditions, the wholesaler can obtain the least costs. Furthermore, this study models the wholesaler's optimal replenishment decisions under the aforementioned conditions in the supply chain management. Two theorems are developed to efficiently determine the optimal replenishment decisions for the wholesaler. Finally, numerical examples are given to illustrate the theorems that are proven in this study, and the sensitivity analysis with respect to the major parameters in this study is performed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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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