Efficient conversion of biomass such as polysaccharides, [1] lignin, [2] and triglycerides [3] to biofuels has attracted considerable attention. Microalgae are being considered in that context as a promising renewable energy resource, having high triglyceride contents (up to 60 wt %) [4] and rapid growth rates that are 10-200 times faster than terrestrial oil crops such as soybean and rapeseed without directly competing with edible food/oil production. [5] Currently, three approaches are used for microalgae oil refining. The first technique involves transesterification of triglycerides and alcohol into fatty acid alkyl esters (FAAEs) and glycerol, which is applied in the first-generation biodiesel production. Such esters, however, have a relatively high oxygen content and poor flow property at low temperatures, limiting their application as high-grade fuels.[6] The second technique employs the conventional hydrotreating catalysts, for example, sulfided NiMo and CoMo, for upgrading. [7] However, these sulfide catalysts contaminate products through sulfur leaching, and deactivate because of its removal from the surface by a reverse Mars-van Krevelen mechanism.[8] The third technique relies on supported noble and base metal catalysts for decarboxylation and decarbonylation of carboxylic acids to alkanes at 300-330 8C, [9] but these catalysts showed low activities and selectivities for C 15 -C 18 alkanes when triglycerides were converted, and the performance was only somewhat improved by a Pt-Re/ZSM-5 catalyst.[10] Contributions addressing microalgae oil upgrading using sulfur-free catalysts have not been reported. Herein, we report for the first time a novel and scalable catalyst, that is, Ni supported on and in zeolite HBeta, to quantitatively convert crude microalgae oil under mild conditions (260 8C, 40 bar H 2 ) to diesel-range alkanes as high-grade secondgeneration transportation biofuels.Microalgae oil mainly consists of neutral lipids such as mono-, di-, and triglyceride. The microalgae oil (provided by Verfahrenstechnik Schwedt GmbH) used for this work consists of unsaturated C 18 fatty acids (88.4 wt %), saturated C 18 fatty acids (4.4 wt %), as well as some other C 14 , C 16 , C 20 , C 22 , and C 24 fatty acids (7.1 wt % in total; see Table S1 in the Supporting Information).Without any purification, the crude microalgae oil was directly hydrotreated in batch mode with 10 wt % Ni/HBeta (Si/Al = 180) at 260 8C and 40 bar H 2 (see Figure 1). After 8 h reaction time, we obtained 78 wt % yield of liquid alkanes (containing 60 wt % yield of C 18 octadecane), which was very close to the theoretical maximum liquid hydrocarbon yield of 84 wt %. Propane (3.6 wt %) and methane (0.6 wt %) were the main products in the vapor phase. The metal leaching after reaction was detected below the atomic absorption spectroscopy (AAS) detection limit (1 ppm). Figure 1 shows that saturated fatty acids were the primary products for microalgae oil conversion, that is, the yield of stearic acid exceeded 70 wt % within 1 h. Then, the...

The reproducible low-cost fabrication of functional metal-polymer nanocomposites with tailored optoelectronic properties for advanced applications remains a major challenge in applied nanotechnology. To obtain full control over the nanostructural evolution at the metal-polymer interface and its impact on optoelectronic properties, we employed combined in situ time-resolved microfocus grazing incidence small angle X-ray scattering (μGISAXS) with in situ UV/vis specular reflectance spectroscopy (SRS) during sputter deposition of gold on thin polystyrene films. On the basis of the temporal evolution of the key scattering features in the real-time μGISAXS experiment, we directly observed four different growth regimes: nucleation, isolated island growth, growth of larger aggregates via partial coalescence, and continuous layer growth. Moreover, their individual thresholds were identified with subnanometer resolution and correlated to the changes in optical properties. During sputter deposition, a change in optical reflectivity of the pristine gray-blue PS film was observed ranging from dark blue color due to the presence of isolated nanoclusters at the interface to bright red color from larger Au aggregates. We used simplified geometrical assumptions to model the evolution of average real space parameters (distance, size, density, contact angle) in excellent agreement with the qualitative observation of key scattering features. A decrease of contact angles was observed during the island-to-percolation transition and confirmed by simulations. Furthermore, a surface diffusion coefficient according to the kinetic freezing model and interfacial energy of Au on PS at room temperature were calculated based on a real-time experiment. The morphological characterization is complemented by X-ray reflectivity, optical, and electron microscopy. Our study permits a better understanding of the growth kinetics of gold clusters and their self-organization into complex nanostructures on polymer substrates. It opens up the opportunity to improve nanofabrication and tailoring of metal-polymer nanostructures for optoelectronic applications, organic photovoltaics, and plasmonic-enhanced technologies.

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Helical symmetry can be found in most flowers with a rotation of contort petal aestivation. For micro- and nanoscale analogies, flower mimicking structures have been reproduced; however, the conceptual chirality of "nanoflowers" has not yet been defined. Here, the chirality of the "flower" was defined by its nanosized chiral structure and consequent optical activity (OA), opening new horizons for the physical theory and chiral materials. We report the surfactant-mediated hydrothermal synthesis of chiral CuO nanoflowers using sodium dodecyl sulfate (SDS) as a structure-directing agent, an amino alcohol as a symmetry-breaking agent, and cupric salt as the inorganic source. Two levels of hierarchical chirality exist for a CuO nanoflower including primary helically arranged "nanoflakes" and secondary helical "subnanopetals" that form "nanopetals". The nanoflowers exhibited a prominent optical response to circularly polarized light (CPL) at the absorption bands characteristic of CuO.

This study is devoted to developing amphiphilic block polymers based on phenylborate ester, which can self-assemble to form nanoparticles, as a glucose-sensitive drug carrier. Poly(ethylene glycol)-block-poly[(2-phenylboronic esters-1,3-dioxane-5-ethyl) methylacrylate] (MPEG5000-block-PBDEMA) was fabricated with MPEG5000-Br as a macroinitiator via atom transfer radical polymerization (ATRP). Using the solvent evaporation method, these block polymers can disperse in aqueous milieu to self-assemble into micellar aggregates with a spherical core-shell structure. Zeta potential and fluorescence techniques analysis showed a good purification effect, high encapsulation efficiency, and loading capacity of fluorescein isothiocyanate (FITC)-insulin-loaded polymeric micelles under optimal conditions. The in vitro insulin release profiles revealed definite glucose-responsive behavior of the polymeric micelles at pH 7.4 and 37 °C, depending on the environmental glucose concentration and the chemical composition of the block polymers. Further, circular dichroism spectroscopy demonstrated that the overall tertiary structure of the released insulin was in great agreement with standard insulin. (1)H NMR results of the polymeric micelles during glucose-responsive process supposed one possible insulin release mechanism via the polymer polarity transition from amphiphilic to double hydrophilic. The analysis of L929 mouse fibroblast cells viability suggested that the polymeric micelles from MPEG5000-block-PPBDEMA had low cell toxicity. The block polymers containing phenylborate ester that responded to changes in the glucose concentration at neutral pH are being aimed for use in self-regulated insulin delivery.