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31.
Copper electrodeposition processes in the hydrogen co-deposition range by the pulsating current (PC) regime were examined by the determination of the average current efficiency of hydrogen evolution and by the scanning electron microscopic (SEM) analysis of the morphology of the formed deposits. The two sets of the square-wave PC of the same pause to pulse ratios, but with different duration of deposition pulses and pauses were analyzed. The one set of square-wave PC was with the constant pause duration and different deposition pulses. In the other set, the deposition pulse was constant while the pause duration was varied. The obtained results were compared with those obtained by electrodeposition at the constant overpotential from solutions of different CuSO4 and H2SO4 concentrations. It was found that the effect of the increasing deposition pulse was equivalent to the decreasing CuSO4 concentration, while the effect of the decreasing pause duration was equivalent to the increasing H2SO4 concentration. It is shown that it is possible to achieve a substitution of more solutions of different CuSO4 and H2SO4 concentartions by the use of the only one solution if the appropriate PC parameters were applied, what can be of high technological significance. 相似文献
32.
Goran Muić 《Mathematische Annalen》2009,343(1):207-227
In this paper we give a construction and study non-vanishing of a class of cusp forms using Poincaré series for a semisimple
algebraic group over a number field. 相似文献
33.
Goran Muić 《manuscripta mathematica》2008,125(2):241-272
In this paper we construct standard intertwining operators for reductive p-adic groups by a method of Bernstein. 相似文献
34.
将微穿孔板吸声结构应用到外加旁支管路的管道声源特性测量方法中,分析和仿真了单层及双层微穿孔板及其后腔结构采用不同参数(板厚、微孔直径、穿孔率、后腔深度等)时改变管道负载声阻抗的作用和影响.研究结果表明:改变板厚、微孔直径、穿孔率、管道横截面积比等参数,可以有效地改变负载声阻;改变后腔深度及微穿孔板与主体管道之间距离,可... 相似文献
35.
Goran Muić 《Monatshefte für Mathematik》2014,173(2):239-256
We use explicit results on modular forms (Mui?, Ramanujan J 27:188–208, 2012) via uniformization theory to obtain embeddings of modular curves and more generally of compact Riemann surfaces attached to Fuchsian groups of the first kind in certain projective spaces. We obtain families of embeddings which vary smoothly with respect to a parameter in the upper-half plane. We study local expression for the divisors attached to the maps in the family. 相似文献
36.
The dependence of the differential resistance r
xx
on the dc current density J
dc in a wide GaAs quantum well with two occupied size quantization subbands has been investigated at the temperature T = 4.2 K in the magnetic fields B < 1 T. A peak, whose position is given by the relation 2R
c
eE
H = ħωc/2, where R
c is the cyclotron radius, E
H is the Hall electric field, and ωc is the cyclotron frequency, has been observed in the r
xx
(J
dc) curves at high filling factors. The experimental results are attributed to Zener tunneling of electrons between the Landau
levels of different subbands. 相似文献
37.
This paper deals with the 2-D finite element shear stress analysis in beams, loaded by bending with shear and St. Venant’s
torsion. The properties of these finite elements, like stiffness matrices as well as load vectors, are derived on the basis
of their axial nodal displacements, e.g. by warping field. Proposed finite elements enable stress analysis independently of
both cross-sectional member shape and material properties. Stiffness matrices and load vectors are derived for several finite
element types. Material is assumed to be isotropic and linear elastic. For justification of the proposed stress analysis procedure,
some examples are presented. 相似文献
38.
Goran Zgrablić Maria Ricci Anna Maria Novello Fulvio Parmigiani 《Photochemistry and photobiology》2010,86(3):507-512
An all-optical experimental technique aimed at measuring photoisomerization quantum yield (ϕ) of the all-trans protonated Schiff base of retinal in solution has been implemented. Upon the increase in the excitation wavelength from 400 to 540 nm a slight increase in ϕ from 0.16 ± 0.03 to 0.20 ± 0.02 is observed in the chromophore dissolved in methanol, whereas the ϕ value of the one dissolved in acetonitrile varies only from 0.22 ± 0.03 (400 nm) to 0.23 ± 0.04 (540 nm). The results suggest that dissipation of the excited-state vibrational energy excess, along with environment-induced modifications of the potential energy surfaces are necessary for an efficient retinal photoisomerization in both solvent and protein environment. 相似文献
39.
Goran N. Kaluđerović Valentina Tayurskaya Reinhard Paschke Sanjiv Prashar Mariano Fajardo Santiago Gómez‐Ruiz 《应用有机金属化学》2010,24(9):656-662
The carboxylate compounds [Ti(η5‐C5H5)(η5‐C5H4{CMe2(CH2CH2CH?CH2)})(O2CCH2SXyl)2] (2; Xyl = 3,5‐Me2C6H3) and [Ti(η5‐C5H5)(η5‐C5H4{CMe2(CH2CH2CH?CH2)})(O2CCH2SMesl)2] (3; Mes 1 = 2,4,6‐Me3C6H2) were synthesized by the reaction of [Ti(η5‐C5H5)(η5‐C5H4{CMe2(CH2CH2CH?CH2)})Cl2] (1) with 2 equivalents of xylylthioacetic acid or mesitylthioacetic acid, respectively. Compounds 2 and 3 were characterized by spectroscopic methods. The cytotoxic activity of 1–3 was tested against human tumor cell lines from four different histogenic origins—8505C (anaplastic thyroid cancer), DLD‐1 (colon cancer) and the cisplatin sensitive A253 (head and neck cancer) and A549 (lung carcinoma)—and compared with those of the reference complex [Ti(η5‐C5H5)2Cl2] (R1) and cisplatin. Surprisingly, the cytotoxic activities of the carboxylate derivatives were lower than those of their corresponding dichloride analogue (1). However, complexes 1–3 were more active than titanocene dichloride against all the studied cells with the exception of complex 2 against A253 and A549 cell lines. DNA‐interaction tests were also carried out. Solutions of all the studied complexes were treated with different concentrations of fish sperm DNA, observing modifications of the UV spectra with intrinsic binding constants of 2.99 × 105, 2.45 × 105, and 2.35 × 105 M ?1 for 1–3. Structural studies based on density functional theory calculations of 2 and 3 were also carried out. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献