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We consider using a battery storage system simultaneously for peak shaving and frequency regulation through a joint optimization framework, which captures battery degradation, operational constraints, and uncertainties in customer load and regulation signals. Under this framework, using real data we show the electricity bill of users can be reduced by up to 12%. Furthermore, we demonstrate that the saving from joint optimization is often larger than the sum of the optimal savings when the battery is used for the two individual applications. A simple threshold real-time algorithm is proposed and achieves this superlinear gain. Compared to prior works that focused on using battery storage systems for single applications, our results suggest that batteries can achieve much larger economic benefits than previously thought if they jointly provide multiple services. [ABSTRACT FROM PUBLISHER]

When participating in electricity markets, owners of battery energy storage systems must bid in such a way that their revenues will at least cover their true cost of operation. Since cycle aging of battery cells represents a substantial part of this operating cost, the cost of battery degradation must be factored in these bids. However, existing models of battery degradation either do not fit market clearing software or do not reflect the actual battery aging mechanism. In this paper we model battery cycle aging using a piecewise linear cost function, an approach that provides a close approximation of the cycle aging mechanism of electrochemical batteries and can be incorporated easily into existing market dispatch programs. By defining the marginal aging cost of each battery cycle, we can assess the actual operating profitability of batteries. A case study demonstrates the effectiveness of the proposed model in maximizing the operating profit of a battery energy storage system taking part in the ISO New England energy and reserve markets. [ABSTRACT FROM AUTHOR]

Two new aporphine alkaloids, (R)-1,2-methylenedioxy-3,9-dimethoxy-11-hydroxy-N- carbamoyl-noraporphine (1) and 3,10,11-trimethoxy-1,2-methylenedioxy-7-oxoaporphine(2), and one new dihydrochalcone, 4′,5′-dimethoxy-2′-hydroxy-3′,6′-quinodihydrochalcone (3), along with five known alkaloids were isolated from the ethanol extracts of the stems of Fissistigma oldhamii var. longistipitatum. The compounds were obtained by various classical column chromatographic methods, and the structure elucidation was completed primarily on the basis of spectroscopic analysis, such as UV, NMR and HR-ESI-MS. The isolated compounds were subjected to evaluate cytotoxic activities in vitro , compound 1 had activity against HL-60 and HELA (IC 50 value of 8.4 μM and 5.2 μM, respectively), compound 2 against MCF-7 (IC 50 value of 3.7 μM), compound 3 against HEPG2 (IC 50 value of 10.8 μM), respectively. [Display omitted] • Three new compounds from the stems of Fissistigma oldhamii var. Longistipitatum. • The structures of new compounds were determined on the basis of 1D and 2D NMR spectroscopy and HR-ESI-MS. • Compound 1 had activity against HL-60 and HELA (IC 50 value of 8.4 μM and 5.2 μM, respectively. • Compound 2 showed activity against MCF-7 (IC 50 value of 3.7 μM), compound 3 against HEPG2 (IC 50 value of 10.8 μM). [ABSTRACT FROM AUTHOR]