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941.
采用循环伏安法,对SPEPt电极以及SPEAu-Pt电极上还原态CO2的电化学氧化行为研究表明,此类电极的电化学特性与光滑Pt电极一致:CO2在氢原子吸附电位区0~250mV(vs.RHE)处,可与电极上化学吸附的氢反应,生成还原态的CO2,通过线性扫描,还原态CO2即发生一不可逆电化学氧化过程(阳极剥离).在SPEPt系列及SPEAu-Pt系列上CO2的电化学行为表明,当SPEPt系列上Pt的载量为2.5mL的0.01mol·L-1H2PtCl6的Pt时,对还原态CO2的电催化活性最好,当Pt的载量相同时,在SPEAu-Pt上,催化剂对还原态CO2的电化学氧化行为比SPEPt电极更强,这是由于预先沉积的Au对后沉积的Pt有调制作用. 相似文献
942.
The magnetic phase diagrams of a two-sublattice ferrimagnet with a magnetically unstable subsystem are calculated taking account
of the susceptibility. Analytic expressions are obtained for the phase-transition fields and critical values of the parameters
of the ferrimagnet. The evolution of the magnetic phase diagrams as the susceptibility of the unstable sublattice increases
is analyzed. 相似文献
943.
We show that when a three-level laser is excited by Poisson light the lasing remains sub-Poisson, as asserted by H. Ritsch,
M. A. M. Marte, and P. Zoller [Europhys. Lett. 19, 7 (1992)], only if there is no reciprocal action on the exciting laser (weak coupling). In cascade schemes in which each
three-level Λ-laser excites each succeeding Λ-laser with its light, any desired degree of shot-noise suppression can be achieved.
Zh. éksp. Teor. Fiz. 114, 1971–1992 (December 1998) 相似文献
944.
Nikolai Yu. Bakaev 《BIT Numerical Mathematics》1998,38(3):462-485
We consider a Cauchy problem for the sectorial evolution equation with generally variable operator in a Banach space. Variable
stepsize discretizations of this problem by means of a strongly A(φ)-stable Runge-Kutta method are studied. The stability
and error estimates of the discrete solutions are derived for wider families of nonuniform grids than quasiuniform ones (in
particular, if the operator in question is constant or Lipschitz-continuous, for arbitrary grids). 相似文献
945.
An analysis is made of a two-electron system of two adjacent quantum dots (QD) with a two-dimensional parabolic lateral confining
potential, and of two coupled or double, spatially separated QDs (a “horizontal” and a “vertical” QD molecule), and of their
behavior in an external transverse magnetic field. The ground-state energies and energy spectra of the system have been determined
by various methods (Heitler-London, molecular-orbital, variational approach, and numerical diagonalization of Hamiltonian),
with inclusion of electron-electron interaction, and for a broad range of confining-potential steepness, QD-center spacing
(interlayer distance), and external magnetic field.
Fiz. Tverd. Tela (St. Petersburg) 40, 2127–2133 (November 1998) 相似文献
946.
A nonlinear model is developed for the photoresponse of a bolometric structure taking into account the temperature dependences
of the thermal constants of the YBaCuO/MgO structure and its boundary thermal resistance. The model also allows for the specific
form of the currentvoltage characteristic of YBaCuO and the heat release from the transport current flow. A comparison between
the experimental data and the model showed that the nonlinear thermal model accurately describes the temporal characteristics
of the photoresponse.
Fiz. Tverd. Tela (St. Petersburg) 40, 191–194 (February 1998) 相似文献
947.
Yu. N. Podil'chuk 《International Applied Mechanics》1993,29(12):969-975
S. P. Timoshenko Institute of Mechanics, Ukrainian Academy of Sciences, Kiev. Translated from Prikladnaya Mekhanika, Vol. 29, No. 12, pp. 15–21, December, 1993. 相似文献
948.
O. A. Brezhneva Yu. G. Evtushenko A. A. Tret’yakov 《Computational Mathematics and Mathematical Physics》2006,46(11):1896-1909
The theory of p-regularity is applied to optimization problems and to singular ordinary differential equations (ODE). The special variant of the method of the modified Lagrangian function proposed by Yu.G. Evtushenko for constrained optimization problems with inequality constraints is justified on the basis of the 2-factor transformation. An implicit function theorem is given for the singular case. This theorem is used to show the existence of solutions to a boundary value problem for a nonlinear differential equation in the resonance case. New numerical methods are proposed including the p-factor method for solving ODEs with a small parameter. 相似文献
949.
S. B. Sakuta B. G. Novatsky D. N. Stepanov D. V. Aleksandrov Yu. A. Glukhov E. Yu. Nikol'sky 《Physics of Atomic Nuclei》2002,65(10):1771-1777
The (6Li, 7Be) and (6Li, 7Li) reactions on 6Li and 7Li nuclei were investigated in the angular interval 0°–20° in the laboratory system at a 6Li energy of 93 MeV. In addition to low-lying states of the 5,6He and 5,6Li nuclei, broad structures were observed near the t(3He)+d and t(3He)+t thresholds at the excitation energies of 16.75 (3/2+) and ~20 MeV (for 5He), 16.66 (3/2+) and ~20 MeV (5Li), 14.0 and 25 MeV (6He), and ~20 MeV (6Li). The angular distributions measured in the 7Li(6Li, 7Be)6He reaction for transitions to the ground state (0+) and excited states at E x=1.8 MeV (2+) and 14.0 MeV of the 6He nucleus were analyzed by the finite-range distorted-wave method assuming the 1p-and 1s-proton pickup mechanism. The (6Li, 7Be) and (6Li, 7Li) reactions were shown to proceed predominantly through the one-step pickup mechanism, and the broad structures observed at high excitation energies are considered as quasimolecular states of the t(3He)+d and t(3He)+t types. 相似文献
950.