Algal blooms occur frequently in Xiangxi Bay (XXB), which is one of the largest tributaries of the Three Gorges Reservoir (TGR). Floating curtain weirs (FCWs) are hydraulic structures that act as a barrier to divert density currents and diffuse heat across the width of the water body. Numerical modeling of FCWs is become a widely accepted method for controlling algal blooms. A laterally averaged two-dimensional hydrodynamic and water quality model (CE-QUAL-W2) was used to simulate the effects of FCWs, including those on water temperature, hydrodynamics and chlorophyll-a concentrations, for XXB. The developed model was calibrated using data collected in XXB from January to December 2010. The results indicated that the maximum chlorophyll-a concentrations observed were 74-154 mg/m 3 at the XX09, XX06 and XX01 sampling sites. The performance of the FCWs suggests that the overall chlorophyll-a concentrations are markedly reduced by more than 85% as a function of the FCW heights and locations. Seasonally, an algal bloom reduction rate of more than 62% was observed in the summer. FCWs with heights of 3, 5, and 7 m reduced algal blooms by up to 99% at XX09 during March 26-28,

A new amorphous semiconductor alloy system Si"C"F~has been prepared by rf sputtering of polycrystalline SiC in an Ar+SiF4 atmosphere. Dark conductivity and optical absorption of thin films are measured as functions of F concentration. Infrared spectra indicate a preferential attachment of fluorine to carbon over silicon. The bonded fluorine concentration is estimated to be as high as 40 at. %. The principal reststrahlen band shifts to higher frequencies and appears to sharpen with the increase of fluorine concentration.Fluorinated films are observed to be resistant to high-temperature annealing.

W-Sb and W-In-Sb thin films were deposited by co-sputtering independent targets on n- and p-type InP wafers. The composition of the films was ascertained by monitoring the sputtering rate of each target. Au was sputtered on the back side and the sandwiched wafers were annealed in a quartz furnace to up to 400 °C. The conduction and diffusion characteristics of the films were studied as a function of the annealing temperatures. The Auger depth profile shows an outdiffusion of In to the surface of the WInSb film. P from the substrate out-diffuses into the W matrix while Sb forms an interfacial In-Sb phase. The x ray diffractogram of samples annealed to 400 °C shows the transition of as-deposited amorphous W into the crystalline state and formation of In-Sb related interfacial phase. The electrical characteristics are ohmic for as-deposited films on n-type material, whereas it becomes ohmic below 400 °C for p-type substrate. The 1000-Å-thick WInSb film when annealed to 400 °C showed a sheet resistance of ∼12 ohm/⧠ and a contact resistance in the 10−6 Ω cm2 range.

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