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排序方式: 共有105条查询结果,搜索用时 78 毫秒
91.
We consider a model of pay-as-clear electricity market based on a Equilibrium Problem with Complementarity Constraints approach where the producers are playing a noncooperative game parameterized by the decisions of regulator of the market (ISO). In the proposed approach the bids are assumed to be convex quadratic functions of the production quantity. The demand is endogenously determined. The ISO problem aims to maximize the total welfare of the market. The demand being elastic, this total welfare take into account at the same time the willingness to pay of the aggregated consumer, as well as the cost of transactions. The market clearing will determine the market price in a pay-as-clear way. An explicit formula for the optimal solution of the ISO problem is obtained and the optimal price is proved to be unique. We also state some conditions for the existence of equilibria for this electricity market with elastic demand. Some numerical experiments on a simplified market model are also provided. 相似文献
92.
Rossana Chiavacci 《Annali dell'Universita di Ferrara》1981,27(1):35-42
Riassunto In questa nota si dimostra che un morfismo adico fra spazi analitici formali è finito se e solo se è quasi-finito; si dimostra
inoltre un teorema di coerenza delle immagini dirette per morfismi 1-convessi fra spazi analitici formali.
Summary In this paper we prove that an adic morphism between formal analytic spaces is finite if and only if it is quasi-finite; moreover we establish a direct image theorem for 1-convex morphisms between formal analytic spaces.相似文献
93.
Giuliana Cardillo Serena Fabbroni Luca Gentilucci Rossana Perciaccante Fabio Piccinelli Alessandra Tolomelli 《Tetrahedron》2004,60(23):5031-5040
An approach to 3-bromo-4-alkyl-6-aryl-5,6-dihydropyridin-2-ones and 3-bromo-5-ethyl-6-aryl-5,6-dihydropyridin-2-ones starting from β,γ-unsaturated α-bromoketenes and imines is reported. The presence of a bromine atom on the double bond allows performing aziridination or bromine displacement with an amine. The reaction gave fused bicyclic N-allyl-aziridines or 3-amino-substituted 5,6-dihydropyridin-2-ones, depending on the substituents on the six-membered ring. 相似文献
94.
Bossi R Rastogi SC Bernard G Gimenez-Arnau E Johansen JD Lepoittevin JP Menné T 《Journal of separation science》2004,27(7-8):537-540
This paper describes a validated liquid chromatographic-tandem mass spectrometric method for quantitative analysis of the potential oak moss allergens atranol and chloroatranol in perfumes and similar products. The method employs LC-MS-MS with electrospray ionization (ESI) in negative mode. The compounds are analysed by selective reaction monitoring (SRM) of 2 or 3 ions for each compound in order to obtain high selectivity and sensitivity. The method has been validated for the following parameters: linearity; repeatability; recovery; limit of detection; and limit of quantification. The limits of detection, 5.0 ng/mL and 2.4 ng/mL, respectively, for atranol and chloroatranol, achieved by this method allowed identification of these compounds at concentrations below those causing allergic skin reactions in oak-moss-sensitive patients. The recovery of chloratranol from spiked perfumes was 96+/-4%. Low recoveries (49+/-5%) were observed for atranol in spiked perfumes, indicating ion suppression caused by matrix components. The method has been applied to the analysis of 10 randomly selected perfumes and similar products. 相似文献
95.
Jared V. Goldstone Rossana Del Vecchio Nell V. Blough Bettina M. Voelker 《Photochemistry and photobiology》2004,80(1):52-60
Light absorption by chromophoric dissolved organic matter (CDOM) plays a number of roles in natural waters, including both control of the underwater light field and the initiation of many photochemical reactions. A multicomponent analysis was used to describe the effects of UV and visible radiation on the optical absorption spectra of two natural water samples, a Suwannee River fulvic acid standard (SRFA) and a Delaware Bay water sample. This analysis used a constrained minimization technique to fit independent spectral components to the observed bleaching behavior of the water samples under monochromatic irradiation. Spectra derived from these fits were used to predict the bleaching behavior of both samples under polychromatic irradiation (λ< 320 nm). This approach reproduces the kinetics and spectral behavior of polychromatic photobleaching very well at times <48 h, but underpredicts the bleaching at longer time periods. 相似文献
96.
TG and DSC investigation of gallstone samples collected from patients submitted to cholecystectomy 总被引:1,自引:0,他引:1
Rossana A. Toscano Dulce M. de A. Melo Maria de F. V. de Moura Robson F. de Farias 《Thermochimica Acta》2004,410(1-2):125-131
In the present work are performed the TG and DSC study of gallstone samples collected from patients submitted to cholecystectomy at the Hospital Universitário Onofre Lopes of Universidade Federal do Rio Grande do Norte, in Natal, Rio Grande do Norte State, Brazil. The gallstone samples were characterized by elemental analysis and infrared spectroscopy. Standard cholesterol was used for all analysis as comparison with the gallstones. Is verified that cholesterol is the main chemical component of all studied gallstone samples. The thermoanalytical study was performed on air and nitrogen atmospheres. The presence of cholesterol as the main chemical component of all gallstone samples is confirmed by TG and DSC results. 相似文献
97.
Stefano Acierno Rossana Pasquino Nino Grizzuti 《Journal of Thermal Analysis and Calorimetry》2009,98(3):639-644
In this article, we show that the crystallization behaviour of a rubber-filled polypropylene, under isothermal conditions,
can be monitored by means of parallel plate rheometry and differential scanning calorimetry. Data collected with different
instruments can be compared only after performance of accurate temperature calibration. The complex modulus as obtained from
dynamic mechanical measurements can be related to the crystalline content by use of appropriate mathematical relationships.
An empirical power law model is used to correlate the crystalline content to the rheological function. Excellent agreement
between rheological and calorimetric data is found. Furthermore, it is shown that rheology can be used to achieve additional
information on the structural evolution of the crystallizing system. 相似文献
98.
Rossana M. S. M. Thiré Taíla O. Meiga Sabrina Dick Leonardo R. Andrade 《Macromolecular Symposia》2007,258(1):38-44
Summary: Chemical modification of polymer surface may potentially be used to create smart materials that can guide cellular adhesion, proliferation and maintenance of specific expression of molecules. The microbial polyester poly (3-hydroxybutyrate) (PHB) has been attracted attention as promising material for applications in tissue engineering. In this work, a wet-chemical method, base ethylenediamine aminolysis, was performed to improve the adhesion of chondrocytes isolated from human articular cartilage to PHB films. The effects of chemical treatment on PHB films was evaluated by following changes in morphology and surface chemical composition using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS), respectively. While the effect on cells morphology was studied by scanning electron microscopy (SEM). The treatment with ethylenediamine did not change significantly the morphology of the structures of PHB films surface. However, the roughness of the aminolyzed films was slightly higher. The introduction of nitrogen-containing groups was confirmed by XPS. In vitro experiments indicated that the surface modification did not have toxic effects in cells, since they could adhere and proliferate on modified PHB films. It was observed that long-time treatment improved ability of PHB films to support cell growth, which could be accounted to physicochemical and topological effects. 相似文献
99.
Boatwright A Besley NA Curtis S Wright RR Stace AJ 《The Journal of chemical physics》2005,123(2):21102
Electronic spectra (S1<--S0) have been recorded from five separate substituted benzene derivatives trapped in helium nanodroplets. Each member of the series is found to exhibit a blueshift with respect to the equivalent transition in the gas phase. Taken together with previous results for benzene, the observed shifts show a remarkably good correlation with changes in electron density that occur within each of the aromatic rings as a result of electronic excitation. 相似文献
100.
Burini A Fackler JP Galassi R Macchioni A Omary MA Rawashdeh-Omary MA Pietroni BR Sabatini S Zuccaccia C 《Journal of the American Chemical Society》2002,124(17):4570-4571
By combining the information from 19F, 1H-HOESY and PGSE NMR methodologies, unprecedented direct evidence has been obtained for the formation of supramolecular assemblies in solution between the trinuclear cyclic AuI basic compounds ([Au(mu-C2,N3-bzim)]3 (bzim = 1-benzylimidazolate), 1, and [Au(mu-C,N-C(OEt)=N-p-C6H4-CH3)]3, 2, on one hand, and the trinuclear cyclic HgII acid complex [Hg(mu-C,C-C6F4)]3, 3, on the other hand. HOESY experiments indicate that a stacking similar to that observed in the solid state occurs. PGSE studies demonstrate the presence of an equilibrium between the free trinuclear entities and adduct A in the case of 2/3 admixtures (see Sketch) while for 1/3 admixtures, adducts A and B are mainly present in solution. 相似文献