Cycling efficiency and rate capability of porous copper-coated, amorphous silicon thinfilm negative electrodes are compared to equivalent silicon thin-film electrodes in lithium-ion batteries. The presence of a copper layer coated on the active material plays a beneficial role in increasing the cycling efficiency and the rate capability of silicon thin-film electrodes. Between 3C and C/8 discharge rates, the available cell energy decreased by 8% and 18% for 40 nm copper-coated silicon and equivalent silicon thin-film electrodes, respectively. Copper-coated silicon thin-film electrodes also show higher cycling efficiency, resulting in lower capacity fade, than equivalent silicon thin-film electrodes. We believe that copper appears to act as a glue that binds the electrode together and prevents the electronic isolation of silicon particles, thereby decreasing capacity loss. Rate capability decreases significantly at higher copper-coating thicknesses as the silicon active-material is not accessed, suggesting that the thickness and porosity of the copper coating need to be optimized for enhanced capacity retention and rate capability in this system.

We demonstrate that electrocoagulation (EC) using iron electrodes can reduce arsenic below 10 µg/L in synthetic Bangladesh groundwater and in real groundwater from Bangladesh and Cambodia while investigating the effect of operating parameters that are often overlooked, such as charge dosage rate. We measure arsenic removal performance over a larger range of current density than in any other single previous EC study (5000 fold: 0.02 -100 mA/cm 2 ) and over a wide range of charge dosage rates (0.

We have prepared a series of gallium(III) complexes of the redox active iminopyridine ligand (IP). Reaction of GaCl(3) with iminopyridine ligand (IP) in the presence of either two or four equivalents of sodium metal resulted in the formation of deep green (IP(-))(2)GaCl (1), or deep purple [(DME)(3)Na][(IP(2-))(2)Ga] (2a), respectively. Complex 1 is paramagnetic with a room temperature magnetic moment of 2.3 μ(B) which falls to 0.5 μ(B) at 5 K. These observations indicate that two ligand radicals comprise a triplet at room temperature which becomes a singlet due to antiferromagnetic coupling at low temperature. Complex 2 is diamagnetic. Cyclic voltammograms recorded on 0.3 M Bu(4)NPF(6) THF solutions of [Na(THF)(6)][(IP(2-))(2)Ga](-) (2b) indicate that oxidation of 2b occurs in two two-electron steps at -1.31 V and -0.54 V vs. SCE. The observation of two-electron redox events indicates that electronic coupling through the gallium(III) center is minimal and that the two IP ligand on 2b are oxidized concurrently. Oxidation of 2 with one equivalent of MeS-SMe afforded the two-electron oxidized product (IP(-))(2)Ga(SMe) (3). This complex has an electronic structure analogous to 1. Accordingly, both 1 and 3 are deep green in color and magnetic susceptibility measurements performed on 3 confirm the triplet character of the complex at room temperature. Electron paramagnetic resonance experiments on 1 and 3 display a quartet signal at g = 2.0 which confirmed the triplet nature of the compounds, and a half field signal consistent with the integer spin state.

Synthesis of substituted phenylacetylide ligands 2,6-bis(trimethylsilyl)phenylacetylene (H1) and 2-(triphenylsilyl)phenylacteylene (H2) is reported. Ligand 1 supports tetrahedral complexes of V(III), Fe(II), and Mn(II) (3-5). Complexes 3-5 are high-spin and redox active.

We describe laboratory and field results of a novel arsenic removal adsorbent called 'Arsenic Removal Using Bottom Ash' (ARUBA). ARUBA is prepared by coating particles of coal bottom l fired power plants, with iron (hydr)oxide. The coating process is * Address correspondence to Ashok Gadgil, Lawrence Berkeley National Laboratory, 1Cyclotron Rd MS 90R3058, Berkeley, CA 94720, USA; Phone: Email: ajgadgil@lbl.gov. 3 simple and conducted at room temperature and atmospheric pressure. Material costs for ARUBA are estimated to be low (~$0.08 per kg) and arsenic remediation with ARUBA has the potential to be affordable to resource-constrained communities. ARUBA is used for removing arsenic via a dispersal-and-removal process, and we envision that ARUBA would be used in community-scale water treatment centers. We show that ARUBA is able to reduce arsenic concentrations in This makes it easy to determine the amount of ARUBA required to treat a groundwater source when its arsenic concentration is known and less than 1600 ppb. Storing contaminated groundwater for two to three days before treatment is seen to significantly increase ARUBA's AAD. ARUBA can be separated from treated water by coagulation and clarification, which is expected to be less expensive than filtration of micron-scale particles, further contributing to the affordability of a community-scale water treatment center.