Search

Abstract As high penetration of uncertain wind and solar energy into power system, spatio-temporal correlation of wind and solar energy is of great necessity for planning and operation of wind farms and PV plants. A Copula function and first order Markov process based Monte Carlo simulation method of multivariate wind speed and PV power spatio-temporal series is proposed in this paper. In the proposed approach, either spatial correlation or temporal correlation of wind speed and PV power series is considered including cross-correlation between all series and self-correlation of every series. The results of case study based on National Renewable Energy Laboratory (NREL) of the U.S. Department of Energy are analyzed, which verify the scientific and feasibility of the proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: The near-stoichiometric LiNbO3 (SLN) single crystals doped Mn2+, Co2+ and Ni2+ in 0.5mol% concentration in the raw compositions were grown by the Bridgman method under the conditions of taking K2O as flux, a high temperature gradient (90–100°C/cm) for solid–liquid interface. The XRD, absorption spectra, excitation spectra and emission spectra have been carried out. From the absorption edges of Mn2+, Co2+ and Ni2+-doped SLN crystals, the molar ratio of [Li+]/[Nb5+] are estimated to be about 0.977. The absorption spectra of Mn2+:SLN have shown a broad absorption band centered at ∼571nm (6A1g(6S)→ 4T1g(4G)), three absorption peaks at 520, 549 and 612nm (overlapping of the 4T1(F)–4A2(F), 4T1(F)–4T1(P)), and a wide absorption band at 1400nm (4T1(F)→ 4T2(F)) of Co2+:SLN, Ni2+:SLN, and five absorption peaks at 381nm (3A2g(F)→ 3T1g(P)), 733nm (3A2g(F)→ 3T1g(F)), 1280nm (3A2g(F)→ 3T2g(F)), 430nm (3A2g(F)→ 1T2g(D)), and 840nm (3A2g(F)→ 1E(D)) of Ni2+:SLN were observed. A red emission at 612nm (4T1g(4G)→ 6A1g(6S)) for Mn2+:SLN, a red emission at 775nm (4T1(P)→ 4T1(F)) for Co2+:SLN, and a green emission at 577nm (1T2g(D)→ 3A2g(F)) and a red emission at 820nm (1T2g(D)→ 3T2g(F)) for Ni2+:SLN were observed under excited by 416, 520 and 550nm lights, respectively. The concentration distribution of Mn2+, Co2+and Ni2+ ion in SLN crystals was investigated primarily from the absorption and emission spectra for various parts. The effective distribution coefficient for Mn2+ was less than 1. While, for Co2+ and Ni2+ were more than 1. [Copyright &y& Elsevier]

[Display omitted] • Triethylamine-responsive QDs based on supramolecular self-assembly was synthesized. • Fluorescence of QD621/ZnS/HPEISA increased greatly after adding triethylamine. • QD621/ZnS/HPEISA supramolecular self-assembly was cleaved by excess triethylamine. • Released QDs/HPEI nanocomposites could easily be endocytosed by the L929 cells. A new strategy for the construction, release and cellular imaging application of triethylamine-responsive fluorescent quantum dots (QDs) based on supramolecular self-assembly has been described. The supramolecular self-assembly (HPEI/SA), which was constructed through the electrostatic interactions between terminal amine groups of hyperbranched polyethylenimines (HPEI) and carboxylic acid groups of stearic acid (SA), first captured aqueous Zn2+ ions into the hydrophilic dendritic core and subsequently encapsulated QDs/S2- by the complexation interactions and reactions between Zn2+ and S2- on QDs. Due to the pH-responsive property of the HPEI/SA supramolecular self-assembly, the fluorescence of encapsulated QDs is sensitive to the triethylamine/SA mole ratio, and the encapsulated QDs can be released to the aqueous phase by cleaving HPEI/SA. The resulting fluorescent QDs/HPEI nanocomposites show promising prospects in bioimaging. [ABSTRACT FROM AUTHOR]

• Nonviral gene vector with folate/magnetism targeting based on hyperbranched polymer. • FA-PEG-HPEI as nanoreactors to prepare superparamagnetic Fe 3 O 4 nanocrystals. • Fe 3 O 4 /FA-PEG-HPEI have higher luciferase expression level than HPEI. A new strategy for in situ preparation of non-viral gene vectors with folate/magnetism dual targeting based on hyperbranched polymers has been described. Folate-PEG-grafted-hyperbranched poly(ethylenimine)s (FA-PEG-HPEI) were synthesized and used as nanoreactors to prepare monodisperse Fe 3 O 4 nanocrystals (NCs). The FA-PEG-HPEI had FA targeting groups, low cytotoxicity and ideal gene transfection performance, while Fe 3 O 4 NCs had superparamagnetic property, thus the resulting Fe 3 O 4 /FA-PEG-HPEI nanocomposites integrated the properties of FA-PEG-HPEI and Fe 3 O 4 NCs together. As expected, the Fe 3 O 4 /FA-PEG-HPEI nanocomposites as non-viral gene vectors with folate/magnetism dual targeting had improved luciferase expression level in HEK 293T and Hela cells under a magnetic gradient field. The luciferase expression level mediated by Fe 3 O 4 /FA-PEG-HPEI nanocomposites in HEK 293T and Hela cells under a magnetic gradient field were 21 and 29 fold of that of standard HPEI transfection, respectively. [ABSTRACT FROM AUTHOR]