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41.
42.
Tamio Kamidate Yasunori Hashimoto Hirofumi Tani Akihiko Ishida 《Analytical sciences》2002,18(3):273-276
The uptake of Cu2+ was investigated using various types of liposomes composed of phosphatidylcholine (PC), cholesterol (Chol) and dicethylphosphate (DCP). DCP played a role as a ligand for Cu2+. Multilamellar vesicles (MLVs) were more effective for the uptake of Cu2+ compared to unilamellar vesicles prepared by the extrusion technique. The uptake efficiency of MLVs for Cu2+ was dependent on the molar ratio of DCP in MLVs. The uptake percent of Cu2+ was 92% using MLVs having a PC:DCP:Chol molar ratio of 4:3:3; 95% of the total vesicle Cu2+ was bound to DCP of the outer membrane surface of the MLVs, and the remaining 5% of the total Cu2+ was distributed into the interior side of the MLVs. MLVs having a PC:DCP:Chol molar ratio of 4:3:3 were also effective as separation media for Mn2+, Co2+, Ni2+ and Zn2+. The uptake efficiency of the MLVs for the transition-metal ions increased in the order Co2+ < Zn2+ < Ni2+ < Mn2+ < Cu2+. 相似文献
43.
44.
Bilinear residue formulas are established for the super-KP hierarchy and the ortho-symplectic super-KP hierarchy. Furthermore, superframes corresponding to the ortho-symplectic super-KP hierarchy are completely characterized. Soliton solutions to the super-KP hierarchy are given. 相似文献
45.
The super-Kadomtsev-Petviashvili (SKP) hierarchy is introduced, and the general solutions are explicitly represented in terms of a superdeterminant. It is proved that the SKP hierarchy can be regarded as a dynamical system on a super-Grassmann manifold of infinite dimensions. 相似文献
46.
Yanagisawa H Hengsberger M Leuenberger D Klöckner M Hafner C Greber T Osterwalder J 《Physical review letters》2011,107(8):087601
Energy distribution curves of laser-induced electron pulses from a tungsten tip have been measured as a function of tip voltage and laser power. Electron emission via tunneling through and/or excitation over the surface barrier from photoexcited nonequilibrium electron distributions are clearly observed. The spectral shapes largely vary with the emission processes and are strongly affected by electron dynamics. Simulations successfully reproduce the spectra, thus allowing direct insight into the involved electron dynamics and revealing the temporal tunability of electron emission via the two experimental parameters. These results should be useful to optimize the pulse characteristics for many applications based on ultrafast laser-induced electron emission. 相似文献
47.
Yasuaki Ueki Takashi Torigoe Hirofumi Ono Ryo Yoshiie Joseph H. Kihedu Ichiro Naruse 《Proceedings of the Combustion Institute》2011,33(2):1795-1800
Gasification technology is recognized as one of the possibilities for utilizing biomass effectively. This study focused on woody biomass gasification fundamentals, using a bench-scale packed-bed reactor. In this experiment, pellets of black pine were gasified, using air as the oxidizing agent. Gasification tests were carried out under both updraft and downdraft conditions. Temperature distributions and compositions of syngas inside the gasifier were continuously monitored during gasification experiments at several ports on the wall of the reactor. The syngas at the exit of the gasifier was also sampled to estimate the amount of tar. Lower heating values of the syngas under updraft and downdraft conditions were 4.8 and 3.8 MJ/m3N, respectively. It was easier to control the height of the packed bed under the downdraft condition than under the updraft condition. Under the updraft condition, a bridging phenomenon occurred. Tar generation under the downdraft condition was lower than that under the updraft condition. This is because tar passes through a partial combustion zone or higher temperature zone in the downdraft gasifier. 相似文献
48.
Hirofumi Shinjoh 《Catalysis Surveys from Asia》2009,13(3):184-190
This paper reviews the progress in our development of the three-way catalyst with a noble metal sintering suppression technology
based on the support anchoring effect. The catalytic activity on this catalyst is far superior to the conventional catalyst,
but with lower noble metal loading. 相似文献
49.
Theoretical and computational methods are powerful in studying transition metal complexes. Our theoretical studies of C–H σ‐bond activation of benzene by Pd(II)–formate complex and that of methane by Ti(IV)‐imido complex successfully disclosed that these reactions are understood to undergo heterolytic σ‐bond activation and the driving force is the formation of strong O–H and N–H bonds in the former and the latter, respectively. Orbital interactions are considerably different from those of σ‐bond activation by oxidative addition. The transmetallation, which is a key process in the cross‐coupling reaction, is understood to be heterolytic σ‐bond activation. Our theoretical study clarified how to accelerate this transmetallation. Also, we wish to discuss weak points in theoretical and computational studies of large systems including transition metal elements, such as the necessity to incorporate solvation effect and to present quantitatively correct numerical results. The importance of solvation effects is discussed in the oxidative addition of methyliodide to Pt(II) complex which occurs in a way similar to an SN2 substitution. To apply the CCSD(T) (coupled cluster singles and doubles with perturbative triples correction) method, which is the gold standard of electronic structure theory, to large system, we need to reduce the size of the system by employing a small model. But, such modeling induces neglects of electronic and steric effects of substitutents which are replaced in the small model. Frontier‐orbital‐consistent quantum‐capping potential (FOC‐QCP) was recently proposed by our group to incorporate the electronic effects of the substituents neglected in the modeling. The CCSD(T) calculation with the FOC‐QCP was successfully applied to large systems including transition metal elements. © 2010 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 10: 000–000; 2010: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.200900019 相似文献
50.
A real-time detection of a moving object was demonstrated by taking the subtraction between cross-polarized phase conjugate waves with fast and slow response times with two kinds of dye-doped phase conjugators. One consists of superposed films of an erythrosin-B-doped film and a methyl-orange-doped film, and the other is a film dispersed with both dyes. The relative phase between cross-polarized phase conjugate waves by the both dye-dispersed films was stable. 相似文献