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91.
Using tunneling spectroscopy, we have measured the local electron energy distribution function in the normal part of a superconductor-normal metal-superconductor (SNS) Josephson junction containing an extra lead to a normal reservoir. In the presence of simultaneous supercurrent and injected quasiparticle current, the distribution function exhibits a sharp feature at very low energy. The feature is odd in energy and odd under reversal of either the supercurrent or the quasiparticle current direction. The feature represents an effective temperature gradient across the SNS Josephson junction that is controllable by the supercurrent. 相似文献
92.
93.
J.M. Macak P.J. Barczuk H. Tsuchiya M.Z. Nowakowska A. Ghicov M. Chojak S. Bauer S. Virtanen P.J. Kulesza P. Schmuki 《Electrochemistry communications》2005,7(12):1417-1422
We explore oxidative electrocatalytic properties of a system consisting of bimetallic Pt/Ru nanoparticles dispersed over a nanotubular self-organized TiO2 matrix. The nanotubular TiO2 layers consist of individual tubes of 100 nm diameter, 500 nm length and 15 nm wall thickness. This nanotubular TiO2 support provides a high surface area and it significantly enhances the electrocatalytic activity of Pt/Ru for methanol oxidation (relative to the performance of Pt/Ru at the same loading but immobilized on a conventional compact TiO2 support). Annealed to anatase, the TiO2 nanotubular support exhibits even higher enhancement effect during electrooxidation of methanol than when used in the “as-formed” amorphous structure. The overall electrocatalytic activity of the system can be further increased by illumination with UV-light (wavelength 325 nm). 相似文献
94.
M. Karny J. Kownacki D. Seweryniak A. Atac B. Cederwall C. Fahlander A. Johnson A. Kerek L. -O. Norlin J. Nyberg E. Adamides E. Ideguchi R. Julin S. Juutinen W. Karczmarczyk S. Mitarai M. Piiparinen R. Schubart G. Sletten S. Törmänen A. Virtanen 《Zeitschrift für Physik A Hadrons and Nuclei》1994,350(3):179-180
Proton rich nuclei close to
100
Sn have been investigated inbeam using the NORDBALL detector array. A beam of 270 MeV58
Ni was used to bombard a
54
Fe target. Reaction channel separation was achieved with a 4 charged particle multi-detector set-up together with a 1 neutron detector wall placed in the forward direction. Gamma-ray transitions belonging to the
111
I nucleus were identified for the first time. A level scheme constructed from --particle-coincidence analysis is proposed. The level structure is discussed within the framework of the shell model and the systematics of the heavier odd iodine nuclei. 相似文献
95.
Mari Granström Jari Kavakka Alistair King Johanna Majoinen Valtteri Mäkelä Juho Helaja Sami Hietala Tommi Virtanen Sirkka-Liisa Maunu Dimitris S. Argyropoulos Ilkka Kilpeläinen 《Cellulose (London, England)》2008,15(3):481-488
Tosylation and acylation of cellulose were performed under mild reaction conditions using imidazolium based ionic liquids
(ILs) as solvents. The non-degradative nature, lower viscosity, as well as higher solubility of cellulose in [amim]Cl encouraged
us to carry out the reactions in this media. The reactions described here were optimised for this particular solvent in order
to obtain different cellulose derivatives with high yields, homogeneity and degree of substitution (DS). Two reagents employed
for the in situ activation of carboxylic acids were N,N′-carbonyldiimidazole (CDI) and 1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide hydrochloride (EDCI). Final products were characterised
by solution and solid-state NMR techniques.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
96.
The paper presents simulation studies targeting high-power narrow-linewidth emission from semiconductor distributed feedback (DFB) lasers. The studies contain analytic and numerical calculations of emission linewidth, side mode suppression ratio and output power for DFB lasers without phase shifts and with \(1\times \lambda /4\) and \(2\times \lambda /8\) phase shifts, taking into account the grating and facets reflectivities, the randomness of the spontaneous emission and the longitudinal photon and carrier density distributions in the laser cavity. Single device structural parameter optimization is generally associated with a trade-off between achieving a narrow linewidth and a high output power. Correlated optimization of multiple structural parameters enables the evaluation of achievable ranges of narrow linewidth and high power combinations. Devices with long cavities and low grating coupling coefficients, \(\kappa\) (keeping \(\kappa L\) values below the levels that promote re-broadening), with AR-coated facets and with a distributed phase-shift have the flattest longitudinal photon and carrier density distributions. This flatness enables stable single-longitudinal-mode operation with high side-mode-suppression ratio up to high injection current densities, which facilitates narrow linewidths and high output powers. The results reported in the paper indicate that Master-Oscillator Power-Amplifier laser structures are needed for achieving W-level high-powers with sub-MHz linewidths because most single-cavity DFB laser structural variations that reduce the linewidth also limit the achievable output power in single-mode operation. 相似文献
97.
Boundary behaviour and normal meromorphic functions 总被引:4,自引:0,他引:4
98.
Langmuir-Blodgett assemblies of 1-palmitoyl-2-pyrenedecanoylphosphatidylcholine and dipalmitoylphosphatidylcholine were transferred from an air/water interface onto germanium or silicon attenuated total reflection (ATR) crystals and were investigated by Fourier transform infrared spectroscopy. A detailed attention has been paid to optimize the deposition conditions and to study the organization of transferred mono- and multimolecular layers. 相似文献
99.
S. Juutinen S. TörmÄnen P. Ahonen B. Cederwall A. Johnson B. Fant R. Julin S. Mitarai J. Mukai J. Nyberg A. Virtanen 《Zeitschrift für Physik A Hadrons and Nuclei》1992,344(2):223-224
The 117Inucleus has been investigated in a high-spin γ-spectroscopic study using the NORDBALL detector array. The observed level structures are interpreted as resulting from coexisting collective prolate and oblate as well as non-collective oblate shapes. 相似文献
100.