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81.
82.
Heinrich Baron 《Monatshefte für Mathematik》1939,47(1):179-180
Ohne ZusammenfassungMit 3 Figuren im Text. 相似文献
83.
Heinrich Baron 《Monatshefte für Mathematik》1937,46(1):377-378
Ohne Zusammenfassung 相似文献
84.
A. Survila S. Kanapeckaité I. Valsiünas V. Yasulaitené 《Russian Journal of Electrochemistry》2010,46(10):1167-1174
Distribution of citrate complexes of Co(II) and Mo(VI) in weakly acidic solutions is analyzed. It is found that the primary
cathodic process is hydrogen evolution. When cathodic polarization is increased, Co(II) reduction is possible, while more
negative potentials may result in full reduction of Mo(VI) to the metallic state. Reduction of H3O+ ions in the solutions of oxyacids occurs with participation of a ligand playing the role of proton donor. Hydrogen evolution
also remains the main electrochemical process in the molybdate solutions. It is assumed that Mo(VI) reduction occurs with
participation of atomic hydrogen, but not all molybdate is reduced to metallic state. Co(II) reduction in solutions containing
Mg(II) occurs to a higher extent but the degree of Mo(VI) reduction depends on the Co(II) concentration: increase in the latter
results in a decrease in the content of metallic molybdenum in coatings. 相似文献
85.
Genovaitė Valiulienė Albina Žielienė Birutė Šimkūnaitė Leonas Naruškevičius Loreta Tamašauskaitė Tamašiūnaitė Vidas Pakštas Algis Selskis 《Journal of Solid State Electrochemistry》2010,14(2):203-212
The electrochemical behavior of Bi2S3 coatings in Watts nickel plating electrolyte was investigated using the cyclic voltammetry, electrochemical quartz crystal
microbalance, X-ray diffraction, and energy dispersive X-ray analysis methods. During the bismuth sulfide coating reduction
in Watts background electrolyte in the potential region from −0.4 to −0.6 V, the Bi2S3 and Bi(III) oxygen compounds are reduced to metallic Bi, and the decrease in coating mass is related to the transfer of S2− ions from the electrode surface. When the bismuth sulfide coating is reduced in Watts nickel plating electrolyte, the observed
increase in coating mass in the potential region −0.1 to −0.4 V is conditioned by Ni2+ ions reduction before the bulk deposition of Ni, initiated by Bi2S3. In this potential region, the reduction of Bi(III) oxygen compounds can occur. After the treatment of as-deposited bismuth
sulfide coating in nickel plating electrolyte at E = −0.3 V, the sheet resistance of the layer decreases from 1013 to 500–700 Ω cm. A metal-rich mixed sulfide Ni3Bi2S2–parkerite is obtained when as-deposited bismuth sulfide coating is treated in Watts nickel plating electrolyte at a potential
close to the equilibrium potential of the Ni/Ni2+ system and then annealed at temperatures higher than 120 °C. 相似文献
86.
Vilija Pautienienė Loreta Tamašauskaitė-Tamašiūnaitė Aloyzas Sudavičius Giedrius Stalnionis Zenonas Jusys 《Journal of Solid State Electrochemistry》2010,14(9):1675-1680
Spontaneous modification of polycrystalline Pt by irreversibly adsorbed bismuth was performed in BiCl3 solution in concentrated hydrochloric acid under open-circuit conditions. After spontaneous modification, followed by extensive
rinsing with water and drying, the surface was characterized using X-ray photoelectron spectroscopy and electrochemistry.
Bi-oxy(chloride), oxide species, and metallic Bi were found at a submonolayer coverage on the Pt surface after spontaneous
modification. The electrochemical response of Bi-modified polycrystalline Pt electrode in sulfuric acid solution exhibits
a complex multi-peak feature, which is resulting in about constant redox charge (Bi species coverage) in the potential region
from 0 to 0.9 V (vs. a standard hydrogen electrode). The spontaneously Bi-modified Pt catalyst in model studies exhibits a
superior activity towards formic acid oxidation at fuel cell anode relevant potentials. The catalytic effect of bismuth oxy-species
is explained in terms of both inhibition of COad formation and oxidation of COad in reaction with Bi-oxy-species. 相似文献
87.
Balčiūnas T Mücke OD Mišeikis P Andriukaitis G Pugžlys A Giniūnas L Danielius R Holzwarth R Baltuška A 《Optics letters》2011,36(16):3242-3244
In this paper we report on the active stabilization of the carrier envelope phase (CEP) of a Yb:KGW chirped pulse amplifier laser system seeded by a Yb-doped solid-state Kerr-lens mode-locked oscillator. The regenerative amplifier delivers 180 fs CEP stable pulses of 30 μJ-1 mJ energy at a repetition rate tunable from 1 to 200 kHz. The bandwidth of the feedback loop was extended by a factor of 5 using a specially designed high-pass filter, which resulted in a dramatic decrease of CEP jitter below 0.45 rad after the amplifier. 相似文献
88.
Algirdas Ambrazevičius Alicija Eismontaitė 《Central European Journal of Mathematics》2013,11(6):1129-1139
A mathematical model of dissociative adsorption and associative desorption for diatomic molecules is generalized. The model is described by a coupled system of parabolic and ordinary differential equations. The existence and uniqueness theorem of the classical solution is proved. 相似文献
89.
90.
E. Mazėtis 《Lithuanian Mathematical Journal》1990,30(3):250-259
Vilnius Pedagigic Institute. Translated from Litovskii Matematicheskii Sbornik (Lietuvos Matematikos Rinkinys), Vol. 30, No. 3, pp. 536–547, July–September, 1990. 相似文献