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排序方式: 共有625条查询结果,搜索用时 15 毫秒
621.
Pedro P. Carvalhinha Anderson Flôres José A. D. Rodrigues Suzana M. Ratusznei Marcelo Zaiat Eugenio Foresti 《Applied biochemistry and biotechnology》2010,162(6):1708-1724
An investigation was performed regarding the application of a mechanically stirred anaerobic sequencing batch biofilm reactor containing immobilized biomass on inert polyurethane foam (AnSBBR) to the treatment of soluble metalworking fluids to remove organic matter and produce methane. The effect of increasing organic matter and reactor fill time, as well as shock load, on reactor stability and efficiency have been analyzed. The 5-L AnSBBR was operated at 30?°C in 8-h cycles, agitation of 400 rpm, and treated 2.0 L effluent per cycle. Organic matter was increased by increasing the influent concentration (500, 1,000, 2,000, and 3,000 mg chemical oxygen demand (COD)/L). Fill times investigated were in the batch mode (fill time 10 min) and fed-batch followed by batch (fill time 4 h). In the batch mode, organic matter removal efficiencies were 87%, 86%, and 80% for influent concentrations of 500, 1,000, and 2,000 mgCOD/L (1.50, 3.12, and 6.08 gCOD/L.d), respectively. At 3,000 mgCOD/L (9.38 gCOD/L.d), operational stability could not be achieved. The reactor managed to maintain stability when a shock load twice as high the feed concentration was applied, evidencing the robustness of the reactor to potential concentration variations in the wastewater being treated. Increasing the fill time to 4 h did not improve removal efficiency, which was 72% for 2,000 mgCOD/L. Thus, gradual feeding did not improve organic matter removal. The concentration of methane formed at 6.08 gCOD/L was 5.20 mmolCH4, which corresponded to 78% of the biogas composition. The behavior of the reactor during batch and fed-batch feeding could be explained by a kinetic model that considers organic matter consumption, production, and consumption of total volatile acids and methane production. 相似文献
622.
We consider the Dirichlet problem for a class of anisotropic degenerate elliptic equations. 相似文献
623.
624.
Baillie N Tkachenko S Zhang J Bosted P Bültmann S Christy ME Fenker H Griffioen KA Keppel CE Kuhn SE Melnitchouk W Tvaskis V Adhikari KP Adikaram D Aghasyan M Amaryan MJ Anghinolfi M Arrington J Avakian H Baghdasaryan H Battaglieri M Biselli AS Branford D Briscoe WJ Brooks WK Burkert VD Carman DS Celentano A Chandavar S Charles G Cole PL Contalbrigo M Crede V D'Angelo A Daniel A Dashyan N De Vita R De Sanctis E Deur A Dey B Djalali C Dodge G Domingo J Doughty D Dupre R Dutta D Ent R Egiyan H 《Physical review letters》2012,108(14):142001
We report on the first measurement of the F(2) structure function of the neutron from the semi-inclusive scattering of electrons from deuterium, with low-momentum protons detected in the backward hemisphere. Restricting the momentum of the spectator protons to ?100 MeV/c and their angles to ?100° relative to the momentum transfer allows an interpretation of the process in terms of scattering from nearly on-shell neutrons. The F(2)(n) data collected cover the nucleon-resonance and deep-inelastic regions over a wide range of Bjorken x for 0.65
相似文献
625.
Paolo Vacca Maria Grazia Maglione Carla Minarini Giovanna Salzillo Eugenio Amendola Dario Della Sala Alfredo Rubino 《Macromolecular Symposia》2005,228(1):263-272
In order to optimize polymer light emitting diode (PLED) performances, devices with holes injected through an Indium Tin Oxide (ITO) / Polyaniline (PANI) electrode into the polymer are much more efficient than devices fabricated with the anode made only by ITO. We demonstrated that by using doped PANI as hole injection layer in a polymer light emitting diode the manufacturing process can become simpler. Indeed, the pattern of conductive layer can be produced without ITO photolithography by UV exposition. As hole transporter layer, Poly(N-vinylcarbazole) (PVK) was spin coated over the doped PANI layer and a layer of tris (8-hydroxy) quinoline aluminum (Alq3) was then thermally evaporated so as to form the electron transport layer. To complete the device structure, Aluminum contacts were deposited onto the organic layers by vacuum evaporation at low pressure. The layers were characterized by X-ray small-angle diffraction, IR Raman and UV-Vis spectroscopies. Devices without PANI and with PANI as HIL were studied. 相似文献