POTENTIAL OF NOSTOC MUSCORUM CULTURED IN BG-II MEDIUM AS BIODIESEL FEEDSTOCK SOURCE: EVALUATION OF NUTRIENT REQUIREMENT FOR CULTURE AND ITS DAILY LIPID CONTENT

Increment of industrial development and energy demands for transportation and electricity have increased diesel-fuel uses to fulfil global energy needs. Carbon emission as impact of high fossil diesel use which pollutes the air gradually increases green house gases (GHG) and increases the intensity of acid rains. Furthermore, scarcity of fossil-fuels resources has caused high price of diesel-fuel which in turn to have increased the prices of all commodities. Nostoc muscorum is filamentous Cyanobacteria species which lives both terrestrial and freshwater aquatic environment. This strain has good ability in producing high biomass and potential in producing lipid. In where, Nostoc muscorum has potential as biodiesel feedstock alternative of food-plants sources. This study was conducting to evaluate the potential of Nostoc muscorum cultured in BG-II medium as biodiesel feedstock source. Evaluation of the nutrient requirement of Nostoc muscorum cultured in BG-II medium was done through assimilation of nitrate (NaNO3)-phosphate (K2HPO4). Biomass production as growth parameter was measured by weighing the dried biomass for 14 days of culture. Daily lipid production was evaluated by lipid extraction using Soxhlet method. The result showed that Nostoc muscorum cultured in BG-II medium required 644.6795 mg/L of NO3- and 25.1566 mg/L of HPO4- with the highest biomass production 0.21 grams/300 mL. Furthermore, Nostoc muscorum as multicellular Cyanobacteria could grow well in BG-II medium at SGR 0.0964 μ/day. Lipid production of Nostoc muscorum during cultivation in BG-II for 14 days decreased day by day. The highest lipid production was reached up in day 4th of culture that was 9.53 mg/g. Based on this study, Nostoc muscorum has good potential as biodiesel feedstock through producing high biomass in BG-II medium. Keywords: Nostoc muscorum, Synechococcus elongatus, Tofu wastewater, Lipid content, Cell disruption, Biodiesel.

Effective Lagrangian of unitary Fermi gas from ε\varepsilon expansion

Using $\varepsilon$ expansion technique proposed in \cite{Nishida:2006br} we derive an effective Lagrangian (Ginzburg-Landau-like functional) of the degenerate unitary Fermi gas to the next-to-leading (NLO) order in $\varepsilon.$ It is demonstrated that for many realistic situations it is sufficient to retain leading order (LO) terms in the derivative expansion. The functional is used to study vortex structure in the symmetric gas, and interface between normal and superfluid phases in the polarized gas. The resulting surface free energy is about four times larger than the value previously quoted in the literature.Comment: 17 pages, 4 figure

Distinct oxygen hole doping in different layers of Sr2CuO4−δ−La2CuO4\rm Sr_{2}CuO_{4-\delta}-La_{2}CuO_4 superlattices

X-ray absorption in $\rm Sr_{2}CuO_{4-\delta}-La_{2}CuO_4$ (SCO-LCO) superlattices shows a variable occupation with doping of a hole state different from holes doped for $x \lesssim x_{optimal}$ in bulk $\rm La_{2-x}Sr_{x}CuO_4$ and suggests that this hole state is on apical oxygen atoms and polarized in the $a-b$ plane. Considering the surface reflectivity gives a good qualitative description of the line shapes of resonant soft X-ray scattering. The interference between superlattice and surface reflections was used to distinguish between scatterers in the SCO and the LCO layers, with the two hole states maximized in different layers of the superlattice

Cationic vacancy induced room-temperature ferromagnetism in transparent conducting anatase Ti_{1-x}Ta_xO_2 (x~0.05) thin films

We report room-temperature ferromagnetism in highly conducting transparent anatase Ti1-xTaxO2 (x~0.05) thin films grown by pulsed laser deposition on LaAlO3 substrates. Rutherford backscattering spectrometry (RBS), x-ray diffraction (XRD), proton induced x-ray emission (PIXE), x-ray absorption spectroscopy (XAS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) indicated negligible magnetic contaminants in the films. The presence of ferromagnetism with concomitant large carrier densities was determined by a combination of superconducting quantum interference device (SQUID) magnetometry, electrical transport measurements, soft x-ray magnetic circular dichroism (SXMCD), XAS, and optical magnetic circular dichroism (OMCD) and was supported by first-principle calculations. SXMCD and XAS measurements revealed a 90% contribution to ferromagnetism from the Ti ions and a 10% contribution from the O ions. RBS/channelling measurements show complete Ta substitution in the Ti sites though carrier activation was only 50% at 5% Ta concentration implying compensation by cationic defects. The role of Ti vacancy and Ti3+ was studied via XAS and x-ray photoemission spectroscopy (XPS) respectively. It was found that in films with strong ferromagnetism, the Ti vacancy signal was strong while Ti3+ signal was absent. We propose (in the absence of any obvious exchange mechanisms) that the localised magnetic moments, Ti vacancy sites, are ferromagnetically ordered by itinerant carriers. Cationic-defect-induced magnetism is an alternative route to ferromagnetism in wide-band-gap semiconducting oxides without any magnetic elements.Comment: 21 pages, 10 figures, to appear in Philosophical Transaction - Royal Soc.

Microscopic mechanisms of spin-dependent electric polarization in 3d oxides

We present a short critical overview of different microscopic models for nonrelativistic and relativistic magnetoelectric coupling including the so-called "spin current scenario", ab-initio calculations, and several recent microscopic approaches to a spin-dependent electric polarization in 3d oxides.Comment: 8 pages, 3 figure