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101.
Emilio L. Cano Javier M. Moguerza Tatiana Ermolieva Yuri Ermoliev 《Computational Management Science》2014,11(1-2):25-44
Due to deregulations of the energy sector and the setting of targets such as the 20/20/20 in the EU, operators of public buildings are now more exposed to instantaneous (short-term) market conditions. On the other hand, they have gained the opportunity to play a more active role in securing long-term supply, managing demand, and hedging against risk while improving existing buildings’ infrastructures. Therefore, there are incentives for the operators to develop and use a Decision Support System to manage their energy sub-systems in a more robust energy-efficient and cost-effective manner. In this paper, a two-stage stochastic model is proposed, where some decisions (so-called first-stage decisions) regarding investments in new energy technologies have to be taken before uncertainties are resolved, and some others (so-called second-stage decisions) on how to use the installed technologies will be taken once values for uncertain parameters become known, thereby providing a trade-off between long- and short-term decisions. 相似文献
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103.
Mikhail Elyashberg Kirill Blinov Yegor Smurnyy Tatiana Churanova Antony Williams 《Magnetic resonance in chemistry : MRC》2010,48(3):219-229
The accuracy of 13C chemical shift prediction by both DFT GIAO quantum‐mechanical (QM) and empirical methods was compared using 205 structures for which experimental and QM‐calculated chemical shifts were published in the literature. For these structures, 13C chemical shifts were calculated using HOSE code and neural network (NN) algorithms developed within our laboratory. In total, 2531 chemical shifts were analyzed and statistically processed. It has been shown that, in general, QM methods are capable of providing similar but inferior accuracy to the empirical approaches, but quite frequently they give larger mean average error values. For the structural set examined in this work, the following mean absolute errors (MAEs) were found: MAE(HOSE) = 1.58 ppm, MAE(NN) = 1.91 ppm and MAE(QM) = 3.29 ppm. A strategy of combined application of both the empirical and DFT GIAO approaches is suggested. The strategy could provide a synergistic effect if the advantages intrinsic to each method are exploited. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
104.
Robson Miranda da Gama Tatiana Santana Balogh Simone França Tânia Cristina Sá Dias Valcinir Bedin André Rolim Baby Jivaldo do Rosário Matos Maria Valéria Robles Velasco 《Journal of Thermal Analysis and Calorimetry》2011,106(2):399-405
This research aimed the effect on Caucasian hair tresses treated with oxidative hair dye, either incorporated or not with
conditioners agents, analyzed by Differential Scanning Calorimetry (DSC) and Thermogravimetric analysis (TG). The formulations
of hair dyes were emulsions oil-in-water with light blond color containing or not the conditioners agents: silanetriol and
panthenol; PEG-12 dimethicone; hydrolyzed silk, hydrolyzed milk protein, and lactose. Each dye (1.5 g) was applied in the
hair tress (2.0 g/20.0 cm of length of Caucasian light-brown), previously treated, more 1.5 g of hydrogen peroxide 20 vol
during 40 min. Evaluation of mass loss of the different hair sample demonstrates that these chemical hair treatments impair
the hair fibers, reduced their moisture content with respect to the untreated hair. The incorporation of conditioners agents
(silanetriol and panthenol; PEG-12 dimethicone; hydrolyzed silk, hydrolyzed milk protein, and lactose) in oxidative hair dyes
types did not decrease the damage caused on the tresses by the coloring process quantified by TG/DTG. However, the DSC curves
demonstrated those conditioners agents (silanetriol and panthenol; PEG-12 dimethicone) dislocated the beginning of the third
event in 20 °C and they inhibited the presence of the fourth event, having characterized thermal protection to the hair. 相似文献
105.
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Motivated by Bonahon’s result for hyperbolic surfaces, we construct an analogue of the Patterson–Sullivan–Bowen–Margulis map
from the Culler–Vogtmann outer space CV (F
k
) into the space of projectivized geodesic currents on a free group. We prove that this map is a continuous embedding and
thus obtain a new compactification of the outer space. We also prove that for every k ≥ 2 the minimum of the volume entropy of the universal covers of finite connected volume-one metric graphs with fundamental
group of rank k and without degree-one vertices is equal to (3k − 3) log 2 and that this minimum is realized by trivalent graphs with all edges of equal lengths, and only by such graphs.
Received: December 2005, Accepted: March 2006 相似文献
108.
Parthasarathy R Bykhovski A Gelmont B Globus T Swami N Woolard D 《Physical review letters》2007,98(15):153906
In this work, a theoretical study of the coupling of TM polarized subterahertz (THz) radiation with periodic semiconductor rectangular slot arrays was conducted, using InSb as an example. Simulation results showed that the structure with 4-12 microm thickness provides over a 20-30-fold increase in the electric field at slot edges in a nanosize region ( approximately 500 nm). The enhancement of the THz electromagnetic field extends across the slots and reaches peak values at the edges due to discontinuity effects. Because of the strong local electromagnetic field enhancement, the structure can potentially be used for the development of novel biophotonic sensors, leading to improved detection sensitivity. 相似文献
109.
Copper‐Mediated Formation of Aryl,Heteroaryl, Vinyl and Alkynyl Difluoromethylphosphonates: A General Approach to Fluorinated Phosphate Mimics
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Maria V. Ivanova Dr. Alexandre Bayle Dr. Tatiana Besset Dr. Thomas Poisson Prof. Dr. Xavier Pannecoucke 《Angewandte Chemie (International ed. in English)》2015,54(45):13406-13410
A general and efficient access to aryl, heteroaryl, vinyl and alkynyl difluoromethylphosphonates is described. The developed methodology using TMSCF2PO(OEt)2, iodonium salts and a copper salt provided a straightforward manifold to reach these highly relevant products. The reaction proved to be highly functional group tolerant and proceeded under mild conditions, giving the corresponding products in good to excellent yields. This method represents the first general synthetic route to this important class of fluorinated scaffolds, which are well‐recognized as in vivo stable phosphate surrogates. 相似文献
110.
Dr. Desmond MacLeod Carey Dr. Tatiana Gomez Dr. Cesar Morales-Verdejo Dr. Alvaro Muñoz-Castro 《ChemistryOpen》2015,4(5):651-655
The complexation of metal cations into a host–guest situation is particularly well exemplified by [2.2.2]paracyclophane and AgI, which leads to a strong cation–π interaction with a specific face of the host molecule. Through this study we sought a deeper understanding of the effects the metal center has on the NMR spectroscopic properties of the prototypical organic host, generating theoretical reasons for the observed experimental results with an aim to determine the role of the cation–π interaction in a host–guest scenario. From an analysis of certain components of the induced magnetic field and the 13C NMR shielding tensor under its own principal axis system (PAS), the local and overall magnetic behavior can be clearly described. Interestingly, the magnetic response of such a complex exhibits a large axis-dependent behavior, which leads to an overall shielding effect for the coordinating carbon atoms and a deshielding effect for the respective uncoordinated counterparts, evidence that complements previous experimental results. This proposed approach can be useful to gain further insight into the local and overall variation of NMR shifts for host–guest pairs involving both inorganic and organic hosts. 相似文献