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101.
Berbeglia Gerardo Rayaprolu Gautam Vetta Adrian 《Annals of Operations Research》2019,274(1-2):131-154
Annals of Operations Research - We study the dynamic pricing problem faced by a monopolistic retailer who sells a storable product to forward-looking consumers. In this framework, the two major... 相似文献
102.
103.
Oprea Simona-Vasilica Bâra Adela Ifrim George Adrian 《Journal of Optimization Theory and Applications》2021,190(1):151-182
Journal of Optimization Theory and Applications - Recent advancements in the sensor industry, smart metering systems and communication technology have led to interesting electricity consumption... 相似文献
104.
Adrian Cǎpritǎ Gheorghe Ilia Rodica Cǎpritǎ 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract A method for the synthesis of esters of 2-(dimethylsulfonium)ethylphos-phonic acid and the results of some trials showing the plant growth regulating activity of these compounds are presented. For the synthesis of the mentioned compounds, dimethyl sulphide is reacted with 2-chloroethylphosphonic acid esters; these esters are obtained through the complex[1] of AlCl3, PCl3 and 1,2-dichloroethan (1). Using the optimum reaction conditions, very good yields were obtained (96–99%). This complex is reacted with different alcohols to give 2-chloroethylphosphonic acid esters (2) (R?Me, Et, Pr, i-Pr, Bu, i-Bu, Pe). Using the optimum reaction conditions, in the case of methanol the maximum obtained yield was 50%. In the case of the other alcohols, the obtained yields were between 76 and 83%. An exception is i-propanol. whose ester was obtained with low yields and the reaction parameters modification have little influence on the yield. The reaction of the esters with dimethyl sulphide gives, in good yields (between 69 and 79%). esters of 2-(dimethylsulfonium)ethylphosphonic acid (3). substances with plant growth regulating activity. 相似文献
105.
Argus Adrian Dunca Kara E. Kohler Monika Neda Leo G. Rebholz 《Mathematical Methods in the Applied Sciences》2012,35(10):1205-1219
This work presents a rigorous analysis of mathematical and physical properties for solutions of multiscale deconvolution turbulence models. We show that solutions of these models exactly conserve model quantities for the integral invariants of fundamental physical importance: kinetic energy, helicity, and (in two dimensions) enstrophy. The kinetic energy conservation is the key that allows us to next apply the phenomenology of homogeneous, isotropic turbulence to establish the existence of a model energy cascade and, in particular, that the cascade exhibits enhanced energy dissipation in a secondary accelerated cascade, which ends at the model's microscale (which we establish is larger than the Kolmogorov microscale). We also prove that the model dissipates energy at the same rate as true turbulent flow, ~ O(U3 ∕ L), independent of Reynolds number. Lastly, we prove the existence of global attractors for the model solutions; the proof of which also shows that solutions are actually one degree of regularity higher than previously known. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
106.
107.
Omer A. Akrawi Gergő Z. Nagy Tamás Patonay Alexander Villinger Peter Langer 《Tetrahedron letters》2012,53(26):3206-3209
Suzuki–Miyaura reactions of 4-trifluoromethylsulfonyloxy-6-bromocoumarin provide a convenient access to arylated coumarins. The reactions proceed with excellent chemoselectivity in favour of position 4. 相似文献
108.
Rodica Cǎpriţǎ Adrian Cǎpriţǎ Ludovic Kurunczi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract The polyphosphates have the capacity of forming chelates with most of that metal cations[l]. Polyphosphatic complexes with trace- and macroelements art used as fodder additives for animals. In our experiments we studied the effect 01pyrophosphate (PP), tripolyphosphate (TPP) and hexametaphosphate (HMP), at different concentrations (0.909 mM, 1.8 I8 mM and 2.727 mM), on the enzymatic activity of carbonic anhydrase (CA), and the effect of polyphosphate chelates or the enzymatic activity of alkaline phosphatase (AP), both zincenzymes. The meta; ion, which can be dissociated in the presence of a chelating agent, is essential foi their catalytic activity 121. The presence of metal atoms as essential constituents of some enzymes, and the metal requirements of others for maximum activity, provide an obvious link between enzymatic reaction and coordination chemistry. 相似文献
109.
Dalma Gyepesov Vratislav Langer 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(2):111-113
The structure analysis of so‐called 9CaO·4CrO3·Cr2O3 proved it to be the title compound, decacalcium hexakis[chromate(V)] chromate(VI), with the simultaneous presence of unusual chromium oxidation states. The structure determination was carried out on a crystal that had inversion twinning. The CrVIO4 tetrahedron is situated on a threefold axis and is disordered over two possible orientations that share three O atoms, while the CrVO4 tetrahedra are in general positions and are ordered. The charge is balanced by Ca2+ cations, one of which is located on a threefold axis. The Ca2+ ions are coordinated by six, seven or eight O atoms. The compound is a significant phase in the CaO–CrOx system and its formation reduces the refractoriness of calcium‐rich compositions in an oxidizing atmosphere. 相似文献
110.
Sebastian Reimann Alina Bunescu Andranik Petrosyan Muhammad Sharif Silke Erfle Constantin Mamat Tariel V. Ghochikyan Ashot S. Saghyan Anke Spannenberg Alexander Villinger Peter Langer 《Helvetica chimica acta》2013,96(10):1955-1967
A variety of 6‐(trichloromethyl)salicylates (=2‐hydroxy‐6‐(trichloromethyl)benzoates) were prepared by TiCl4‐mediated cyclization of 1,3‐bis(trimethylsilyloxy)buta‐1,3‐dienes with 1,1,1‐trichloro‐4,4‐dimethoxybut‐3‐en‐2‐one. The employment of trimethylsilyl trifluoromethanesulfonate (Me3SiOTf) as Lewis acid resulted in the formation of trichloromethyl‐substituted cyclohexenones. The cyclizations proceeded with good‐to‐very‐good regioselectivities. 相似文献