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991.
Duong Thuc-Huy Tran Thi-Minh-Dinh Pham Nguyen-Kim Tuyen Mai Tri-Dinh Nguyen Huu-Hung Nguyen Ngoc-Hong Sichaem Jirapast 《Chemistry of Natural Compounds》2022,58(5):862-865
Chemistry of Natural Compounds - A new C41-spiroterpenoid, norreticulatin (1), has been isolated from the thalli of Parmotrema cristiferum together with four known compounds, anadensin (2),... 相似文献
992.
Journal of Global Optimization - The aim of this paper is to establish new results on the error bounds for a class of vector equilibrium problems with partial order provided by a polyhedral cone... 相似文献
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995.
Coralie Caron Xuan N. T. Duong Dr. Régis Guillot Dr. Sophie Bombard Dr. Anton Granzhan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(8):1949-1962
Ligands interacting with abasic (AP) sites in DNA may generate roadblocks in base-excision DNA repair (BER) due to indirect inhibition of DNA repair enzymes (e.g., APE1) and/or formation of toxic byproducts, resulting from ligand-induced strand cleavage or covalent cross-links. Herein, a series of 12 putative AP-site ligands, sharing the common naphthalenophane scaffold, but endowed with a variety of substituents, have been prepared and systematically studied. The results demonstrate that most naphthalenophanes bind to AP sites in DNA and inhibit the APE1-induced hydrolysis of the latter in vitro. Remarkably, their APE1 inhibitory activity, as characterized by IC50 and KI values, can be directly related to their affinity and selectivity to AP sites, as assessed by means of fluorescence melting experiments. On the other hand, the molecular design of naphthalenophanes has a crucial influence on their intrinsic AP-site cleavage activity (i.e., ligand-catalyzed β- and β,δ-elimination reactions at the AP site), as illustrated by the compounds either having an exceptionally high AP-site cleavage activity (e.g., 2,7-BisNP-S , 125-fold more efficacious than spermine) or being totally devoid of this activity (four compounds). Finally, the unprecedented formation of a stable covalent DNA adduct upon reaction of one ligand ( 2,7-BisNP-NH ) with its own product of the AP-site cleavage is revealed. 相似文献
996.
Minh Duy Le Mickaël Matrat Arij Ben Amara Fabrice Foucher Bruno Moreau Yi Yu Pierre-Alexandre Glaude 《Proceedings of the Combustion Institute》2021,38(1):441-448
An in-depth understanding of fuel additives chemical effects is crucial for optimal use or additive design dedicated to more efficient and cleaner combustion. This study aims at investigating the effect of an organometallic octane booster additive named ferrocene on the combustion of a low-octane gasoline at engine-relevant conditions. Rapid compression machine experiments were carried out at 10 bar, from 675 to near 1000 K for stoichiometric (Φ = 1) and lean (Φ = 0.5) mixtures. The neat surrogate fuel was a blend of toluene and n-heptane whose research octane number was 84. The doping level of additive was set at 0.1% molar basis. Ferrocene does not show a remarkable effect on the 1st- stage ignition but presents a strong inhibiting effect on the main ignition of the surrogate fuel at both equivalence ratios. The inhibiting effect increases with temperature within the investigated range. The negative temperature coefficient (NTC) behavior of the surrogate fuel is enhanced by ferrocene. A kinetic model developed by literature data assembly as well as a novel sub-mechanism involving the formation of alcohols from the reactions of iron species is proposed. The kinetic model developed simulates the inhibiting effect of ferrocene reasonably well at both equivalence ratios. Thanks to the validated kinetic model, the chemical effect of ferrocene on the fuel combustion is explored and compared with 2-ethylhexyl nitrate (EHN), which is a conventional reactivity enhancer. Three major differences between the two additives were identified: the high-temperature stability of the fuel additive, the influence of additive on the toluene reactivity and the effect of the additive on the NTC behavior. The results presented in this study contribute to the in-depth comprehension of chemical effect of two fuel additives (ferrocene and EHN) having opposite effects on fuel reactivity. 相似文献
997.
Cao Van-Chung Vo Anh-Tuan Le Quang-Thanh Le Ngoc-Thiem Duong Trung H. Tran Hoai-Nam 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):609-617
Journal of Radioanalytical and Nuclear Chemistry - Depth-dose profiles of electron radiation in continuous and discontinuous materials of water, plastic and food-like dummy irradiated by 10 MeV... 相似文献
998.
Blaauw M. Ridikas D. Baytelesov S. Salas P. S. Bedregal Chakrova Y. Eun-Ha Cho Dahalan R. Fortunato A. H. Jacimovic R. Kling A. Muñoz L. Mohamed N. M. A. Párkányi D. Singh T. Van Dong Duong 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(1):409-418
Journal of Radioanalytical and Nuclear Chemistry - Molybdenum-99 is one of the most important radionuclides for medical diagnostics. In 2015, the International Atomic Energy Agency organized a... 相似文献
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1000.
Ha Pham Hoang Hanh Dang Dinh Loan Nguyen Thanh Pham Ngoc Diep 《Czechoslovak Mathematical Journal》2021,71(3):697-708
Czechoslovak Mathematical Journal - Let T be a tree. Then a vertex of T with degree one is a leaf of T and a vertex of degree at least three is a branch vertex of T. The set of leaves of T is... 相似文献