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891.
Takuya Kuwahara Keiichiro Yoshida Tomoyuki Kuroki Kenichi Hanamoto Kazutoshi Sato Masaaki Okubo 《Plasma Chemistry and Plasma Processing》2014,34(1):65-81
Regulations governing marine diesel engine NOx emissions have recently become more stringent. As it is difficult to fulfill these requirements by combustion improvements alone, effective aftertreatment technologies are needed to achieve efficient NOx reductions. In this study, we develop an effective NOx-reduction aftertreatment system for a marine diesel engine that employs combined nonthermal plasma (NTP) and adsorption. Compared with selective catalytic reduction, the proposed technology offers the advantages of not requiring a urea solution or harmful heavy-metal catalysts and low operating temperatures of less than 150 °C. The NOx reduction comprises repeated adsorption and desorption flow processes using NTP combined with NOx adsorbents made of MnOx–CuO. High concentrations of NOx are treated by NTP after NOx adsorption and desorption, and this aftertreatment system demonstrates excellent energy efficiencies of 161 g(NO2)/kWh, which fulfills the most recent International Maritime Organization emission NOx standards in the Tier II–III regulations for 2016 and requires only 4.3 % of the engine output power. 相似文献
892.
We consider a class of second order quasilinear differential equations with singular ninlinearities. Our main purpose is to investigate in detail the asymptotic behavior of their solutions defined on a positive half-line. The set of all possible positive solutions is classified into five types according to their asymptotic behavior near infinity, and sharp conditions are established for the existence of solutions belonging to each of the classified types. 相似文献
893.
ZnO crystals were synthesized from basic aqueous solutions including zincate ions stabilized with triethanolamine (N(C2H4OH)3, teaH3) by heating at 60°C. The influence of the basicity of the solutions on the morphology of the ZnO crystals was examined. The aqueous solutions were prepared using ZnSO4·7H2O, N(CH3)4OH (TMAOH), and teaH3 as a zinc source, a base, and a stabilizer, respectively, at a zinc concentration of 0.2 M at a teaH3 / Zn molar ratio of 4. Clear solutions were obtained at a molar ratio of TMAOH / Zn ≥ 3.0. When the clear solutions, in which glass or polyester substrates were placed, were heated at 60°C, agglomerates of ZnO crystals were deposited on the substrates in the TMAOH / Zn range from 3.0 to 3.6. With increasing the TMAOH / Zn ratio, the shape of the resulting ZnO crystals changed from a short asymmetric column with a hexagonal flat edge and a rounded one, through a rocket‐like shape formed by intergrowth, to a hexagonal rod. Although no films of ZnO were formed, ZnO crystals with different shapes were synthesized. When the glass substrates pre‐coated with a ZnO thin film by a sol‐gel method were used, highly oriented, dense ZnO films were formed. The films consisted of rod‐like crystals aligned normal to the substrate surface. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
894.
Hiromi Kitano Yasushi Maeda Kanae Furukawa Takahiro Yamamoto Rie Izumida Seiichi Matsugo 《Photochemistry and photobiology》1995,62(5):809-812
Abstract— -Modification of an enzyme, α-chymotrypsin, was examined by using a water-soluble photo-Fenton reagent. By photoirradiation of the enzyme with the reagent, which can occupy a binding site of the enzyme, a tryptophan residue in the vicinity of the active site was oxidized to N -formylkynurenine. Concurrently, the catalytic properties of the enzyme were largely changed: the K m was increased and the k cat was decreased. The decrease in k cat for a specific amide substrate was the most significant among the esters and amides examined. The water-soluble photo-Fenton reagent would be useful to chemically modify relatively limited regions in biomolecules. 相似文献
895.
Heat capacity of α-NH4HgCl3 crystal has been measured with an adiabatic calorimeter from 11 to 300 K. A sharply peaked anomaly due to an order-disorder change of the ammonium ions was found at 54.97 ± 0.04 K. The entropy and enthalpy changes were estimated to be ΔS = 5.2 ± 1.0JK?1 mol?1 and ΔH = 342 ± 65 J mol?1. In accordance withthe structural two-dimensionality of α-NH4HgCl3 crystal, Onsager's solution of the two-dimensional Ising model was used in calculation of the transition temperature. On the assumption that the octopole-octopole interaction is responsible for the ordering of the ammonium ions in the present crystal and in ammonium chloride, the calculation gives 74.44 K for the transition temperature. Several possibilities were discussed for explaining the remaining discrepancy between the observed and calculated transition temperatures. 相似文献
896.
Newly developed orthogonal aberration functions are reviewed. The new functions can be utilized to express aberrations of a high NA and wide field optical system like a microlithographic projection lens. The new functions are orthogonal to each other and expressed by a simple combination of Zernike function(s) of pupil coordinates and Zernike function(s) of field coordinates. 相似文献
897.
898.
899.
[Ni3O(TBPLA)(H2O)](ClO4)4(H2O)6 [TBPLA=(S)-1,1′,1″-2,4,6-trimethylbenzene-1,3,5-triyl)-tris(methylene)-tris-(pyrrolidine-2-carboxylate)] was found to possibly display multiferroic property (the coexistence of ferroelectricity and ferromagnetism). The magnetic property of this compound was studied and no magnetic hysteresis loop was found probably due to an intrinsic fluctuation for the magnetic exchange energy. 相似文献
900.