@article{213,
abstract = {For any integers d,n ≥2, let X ⊂ Pn be a non‐singular hypersurface of degree d that is defined over the rational numbers. The main result in this paper is a proof that the number of rational points on X which have height at most B is O(Bn − 1 + ɛ), for any ɛ > 0. The implied constant in this estimate depends at most upon d, ɛ and n. 2000 Mathematics Subject Classification 11D45 (primary), 11G35, 14G05 (secondary).},
author = {Timothy Browning and Heath-Brown, Roger and Starr, Jason M},
journal = {Proceedings of the London Mathematical Society},
number = {2},
pages = {273 -- 303},
publisher = {John Wiley and Sons Ltd},
title = {{The density of rational points on non-singular hypersurfaces, II}},
doi = {https://doi.org/10.1112/S0024611506015784},
volume = {93},
year = {2006},
}
@article{2134,
abstract = {Predissociation of the N+2 C 2Σ+u(v') vibrational levels with v' ≥ 3 was observed via dispersed C 2Σ+u → X 2Σ+g fluorescence in the spectral range of 165–208 nm after resonant 1s−1π*(vr) excitation of N2 and its subsequent autoionization into the N+2 C state. This range is dominated by lines in atomic nitrogen, by overlapped C 2Σ+u(v') → X 2Σ+g(v'') vibrational band sequences with Δv = const and broad unresolved band systems (D, (2))2Πg(v') → A2Πu(v'') in the N+2 molecular ion. With very high fluorescence resolution of about 0.1 nm FWHM individual C 2Σ+u(v') → X 2Σ+g(v'') vibrational bands have been resolved. Calculation of the observed fluorescence spectra by taking into account predissociation and molecular rotation describes well the shape of both individual vibrational bands C 2Σ+u(v') → X 2Σ+g(v'') and the whole band system.},
author = {Ehresmann, Arno and Werner, Lutz and Klumpp, Stefan and Demekhin, Ph V and Mikhail Lemeshko and Sukhorukov, V. L and Schartner, Karl H and Schmoranzer, Hans P},
journal = {Journal of Physics B: Atomic, Molecular and Optical Physics},
number = {6},
pages = {L119 -- L126},
publisher = {IOP Publishing Ltd.},
title = {{Predissociation of the N+2(C 2Σ+u) state observed via C 2Σ+u → X 2Σ+g fluorescence after resonant 1s−1π* excitation of N2 molecule}},
doi = {10.1088/0953-4075/39/6/L03},
volume = {39},
year = {2006},
}
@article{2142,
abstract = {Fluorescence from fragments formed after the de-excitation of the N*2(1s−1π*) resonance has been measured in the spectral range of 135–190 nm. This range is dominated by lines in atomic nitrogen and lines formed by overlapping C2Σ+u(v') → X2Σ+g(v'') bands with Δv = const in the N+2 molecular ion which result from the spectator Auger decays of the N*2(1s−1π*(vr)) resonances. Ab initio calculations of the corresponding potential curves and transition probabilities showed that the observed irregular intensity dependence of the C2Σ+u(v') → X2Σ+g(v'')(Δv = const) fluorescence lines on the vibrational quantum number vr is due to transitions between vibrational levels during the reaction N2(v0 = 0)→ N*2(1s−1π*(vr)) Longrightarrow C2Σ+u(v') → X2Σ+g(v'').},
author = {Ehresmann, Arno and Werner, Lutz and Klumpp, Stefan and Lucht, S and Schmoranzer, Hans P and Mickat, Sascha and Schill, Rüdiger H and Schartner, Karl H and Demekhin, Philipp and Mikhail Lemeshko and Sukhorukov, Victor L},
journal = {Journal of Physics B: Atomic, Molecular and Optical Physics},
number = {2},
pages = {283 -- 304},
publisher = {IOP Publishing Ltd.},
title = {{Studying the N+2(C2Σ+u → X2Σ+g) fluorescence excited via the 1s−1π* resonance}},
doi = {10.1088/0953-4075/39/2/006},
volume = {39},
year = {2006},
}
@article{2144,
abstract = {Temperature dependent preedge and extended x-ray absorption fine structure measurements at the Zr K edge for the perovskite-type zirconates Pb Zr0.515 Ti0.485 O3 (PZT), PbZr O3 (PZ), and BaZr O3 are performed. To carry out a more accurate study of the weak reconstruction of the local atomic structure we employed a combination of two techniques: (i) analysis of the preedge fine structure, and (ii) analysis of the Fourier transform of the difference between χ (k) functions obtained at different temperatures. A detailed investigation of local atomic structure in the cubic phase for all the crystals is also performed. It is shown that neither the displacive nor the order-disorder model can describe correctly the changes of local atomic structure during phase transitions in PZ and PZT. A spherical model describing the local atomic structure of perovskite-type crystals suffering structural phase transitions is proposed.},
author = {Vedrinskiǐ, Rostislav V and Nazarenko, Elena S and Mikhail Lemeshko and Nassif, Vivian M and Proux, Olivier and Novakovich, Alexander A and Joly, Yves},
journal = {Physical Review B - Condensed Matter and Materials Physics},
number = {13},
publisher = {American Physical Society},
title = {{Temperature dependent XAFS studies of local atomic structure of the perovskite-type zirconates}},
doi = {10.1103/PhysRevB.73.134109},
volume = {73},
year = {2006},
}
@article{215,
abstract = {For any n≥3, let F ∈ Z[X0,...,Xn ] be a form of degree d *≥5 that defines a non-singular hypersurface X ⊂ Pn . The main result in this paper is a proof of the fact that the number N (F ; B) of Q-rational points on X which have height at most B satisfiesN (F ; B) = Od,ε,n (Bn −1+ε ), for any ε > 0. The implied constant in this estimate depends at most upon d, ε and n. New estimates are also obtained for the number of representations of a positive integer as the sum of three dth powers, and for the paucity of integer solutions to equal sums of like polynomials.*},
author = {Timothy Browning and Heath-Brown, Roger},
journal = {Bulletin of the London Mathematical Society},
number = {3},
pages = {401 -- 410},
publisher = {Wiley-Blackwell},
title = {{The density of rational points on non-singular hypersurfaces, I}},
doi = {10.1112/S0024609305018412},
volume = {38},
year = {2006},
}
@article{216,
abstract = {For any N ≥ 2, let Z ⊂ ℙN be a geometrically integral algebraic variety of degree d. This article is concerned with the number Nz(B) of ℚ-rational points on Z which have height at most B. For any ε > 0, we establish the estimate NZ(B) = O d,ε,N(Bdim Z+ε), provided that d ≥ 6. As indicated, the implied constant depends at most on d, ε, and N.},
author = {Timothy Browning and Heath-Brown, Roger and Salberger, Per},
journal = {Duke Mathematical Journal},
number = {3},
pages = {545 -- 578},
publisher = {Unknown},
title = {{Counting rational points on algebraic varieties}},
doi = {10.1215/S0012-7094-06-13236-2},
volume = {132},
year = {2006},
}
@article{218,
abstract = {This paper is concerned with the average order of certain arithmetic functions, as they range over the values taken by binary forms.},
author = {de la Bretèche, Régis and Timothy Browning},
journal = {Acta Arithmetica},
number = {3},
pages = {291 -- 304},
publisher = {Instytut Matematyczny},
title = {{Sums of arithmetic functions over values of binary forms}},
doi = {10.4064/aa125-3-6},
volume = {125},
year = {2006},
}
@inproceedings{7326,
abstract = {Often the properties of a single cell are considered as representative for a complete polymer electrolyte fuel cell stack or even a fuel cell system. In some cases this comes close, however, in many real cases differences on several scales become important. Cell interaction phenomena in fuel cell stacks that arise from inequalities between adjacent cells are investigated in detail experimentally. For that, a specialized 2-cell stack with advanced localized diagnostics was developed. The results show that inequalities propagate by electrical coupling, inhomogeneous cell polarization and inducing in-plane current in the common bipolar plate. The effects of the different loss-mechanisms are analyzed and quantified. },
author = {Büchi, Felix N. and Freunberger, Stefan Alexander and Santis, Marco},
booktitle = {ECS Transactions},
location = {Cancun, Mexico},
number = {1},
pages = {963--968},
publisher = {ECS},
title = {{What is learned beyond the scale of single cells?}},
doi = {10.1149/1.2356215},
volume = {3},
year = {2006},
}
@article{7327,
abstract = {Propagation of performance changes to adjacent cells in polymer electrolyte fuel cell stacks is studied by means of voltage monitoring and local current density measurements in peripheral cells of the stack. A technical fuel cell stack has been modified by implementing two independent reactant and coolant supplies in order to deliberately change the performance of one cell (anomalous cell) and study the coupling phenomena to adjacent cells (coupling cells), while keeping the working conditions of the later cell-group unaltered.
Two anomalies are studied: (i) air starvation and (ii) thermal anomaly, in a single anomalous cell in the stack and their coupling to adjacent cells. The results have shown that anomalies inducing considerable changes in the local current density of the anomalous cell (such as air starvation) propagate to adjacent cells affecting their performance. The propagation of local current density changes takes place via the common bipolar plate due to its finite thickness and in-plane conductivity. Consequently, anomalies which do not strongly influence the local current density distribution (such as a thermal anomaly under the studied working conditions) do not propagate to adjacent cells.},
author = {Santis, Marco and Freunberger, Stefan Alexander and Papra, Matthias and Wokaun, Alexander and Büchi, Felix N.},
issn = {0378-7753},
journal = {Journal of Power Sources},
number = {2},
pages = {1076--1083},
publisher = {Elsevier},
title = {{Experimental investigation of coupling phenomena in polymer electrolyte fuel cell stacks}},
doi = {10.1016/j.jpowsour.2006.06.007},
volume = {161},
year = {2006},
}
@article{7328,
abstract = {An experimental technique for measuring the current density distribution with a resolution smaller than the channel/rib scale of the flow field in polymer electrolyte fuel cells (PEFCs) is presented. The electron conductors in a plane perpendicular to the channel direction are considered as two-dimensional resistors. Hence, the current density is obtained from the solution of Laplace's equation with the potentials at current collector and reaction layer as boundary conditions. Using ohmic drop for calculating the local current, detailed knowledge of all resistances involved is of prime importance. In particular, the contact resistance between the gas diffusion layer (GDL) and flow field rib, as well as GDL bulk conductivity, are strongly dependent on clamping pressure. They represent a substantial amount of the total ohmic drop and therefore require careful consideration. The detailed experimental setup as well as the concise procedure for quantitative data evaluation is described. Finally, the method is applied successfully to a cell operated on pure oxygen and air up to high current densities. The results show that electrical and ionic resistances seem to govern the current distribution at low current regimes, whereas mass transport limitations locally hamper the current production at high loads.},
author = {Freunberger, Stefan Alexander and Reum, Mathias and Evertz, Jörg and Wokaun, Alexander and Büchi, Felix N.},
issn = {0013-4651},
journal = {Journal of The Electrochemical Society},
number = {11},
publisher = {The Electrochemical Society},
title = {{Measuring the current distribution in PEFCs with sub-millimeter resolution}},
doi = {10.1149/1.2345591},
volume = {153},
year = {2006},
}