The feasibility of using silicon as an alloying agent for the negative electrode in normalLi/FeS2 cells was determined by studying cells of the typeLi liq or 40 a/o Li‐Al alloy solLiCl‐KCl eutectic or LiF‐LiCl‐LiBr meltsLi  in solid Li‐Si alloys at equilibrium The Li‐Si electrode was found reversible with respect to lithium between 650° and 725°K. The nonstoichiometry ranges of the respective Li‐Si compounds and electromotive forces (emf's) in the two‐phase regions of the Li‐Si phase diagram between 650° and 750°K were measured. These studies indicated a new compound, Li21Si8 , which was confirmed by x‐ray diffraction, scanning electron microscope, and differential thermal analysis. The activities and relative partial molar properties of lithium and silicon in the two‐phase regions of the phase diagram were calculated from the emf's in the temperature range 650°–750°K, and the standard free energy of formation for the compounds Li2normalSi , Li21Si8 , Li15Si4 , and Li22Si5 , were also determined.

A fullerene-C 60 -modified gold electrode is employed for the determination of dopamine in the excess of ascorbic acid using square-wave voltammetry. Based on its strong catalytic function towards the oxidation of dopamine and ascorbic acid, the overlapping voltammetric response of both the biomolecules at the bare electrode is resolved into two welldefined voltammetric peaks with lowered oxidation potential and enhanced oxidation currents. Linear calibration curves for dopamine are obtained using square-wave voltammetry over the concentration range 1 nM -5.0 mM in 0.1 M phosphate buffer solution at pH 7.2 with a correlation coefficient of 0.9931 and the detection limit (3s) is estimated to be 0.26 Â 10 À9 M. The interference studies showed that the presence of physiologically common interferents (i.e. uric acid, citric acid, tartaric acid, glucose and sodium chloride) negligibly affects the response of dopamine. The practical analytical utility of the method is illustrated by quantitative determination of dopamine in commercially available pharmaceutical formulation and human body fluids, viz. urine and blood plasma, without any preliminary treatment.

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As detailed structural characterizations of large complex DNA nanostructures are hard to obtain experimentally, particularly if they have substantial flexibility, coarse-grained modeling can potentially provide an important complementary role. Such modeling can provide a detailed view of both the average structure and the structural fluctuations, as well as providing insight into how the nanostructure's design determines its structural properties. Here, we present a case study of jointed DNA nanostructures using the oxDNA model. In particular, we consider archetypal hinge and sliding joints, as well as more complex structures involving a number of such coupled joints. Our results highlight how the nature of the motion in these structures can sensitively depend on the precise details of the joints. Furthermore, the generally good agreement with experiments illustrates the power of this approach and suggests the use of such modeling to prescreen the properties of putative designs.

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