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1.
Pallares J. Marsal L.F. Correig X. Calderer J. Alcubilla R. 《Electron Devices, IEEE Transactions on》1998,45(1):54-61
This paper addresses the problem of the space charge region Shockley-Read-Hall (SRH) recombination currents in heterojunctions with one noncrystalline side. A formulation which generalizes previous works is discussed. The approach is based on the drift-diffusion model with a thermionic-field emission boundary condition. The main physical parameters which determine the relative contribution of each zone of the space charge region (SCR) to the total recombination current are identified. The general analysis is applied for the first time to amorphous/crystalline heterojunctions and design criteria are established to minimize the total recombination current 相似文献
2.
Philips K. Nuijten P.A.C.M. Roovers R.L.J. van Roermund A.H.M. Chavero F.M. Pallares M.T. Torralba A. 《Solid-State Circuits, IEEE Journal of》2004,39(12):2170-2178
Receivers are being digitized in a quest for flexibility. Analog filters and programmable gain stages are being exchanged for digital processing at the price of a very challenging ADC. This paper presents an alternative solution where the filter and programmable gain functionality is integrated into a /spl Sigma//spl Delta/ ADC. The novel filtering ADC is realized by adding a high-pass feedback path to a conventional /spl Sigma//spl Delta/ ADC while a compensating low-pass filter in the forward path maintains stability. As such, the ADC becomes highly immune to interferers even if they exceed the maximum allowable input level for the wanted channel. As a consequence, the ADC input range can be programmed dynamically to the level of the wanted signal only. This results in an input-referred dynamic range of 89 dB in 1-MHz bandwidth and an intentionally moderate output signal-to-noise-and-distortion ratio of 46-59 dB (depending on the programmed gain). The merged functionality enables a better overall power/performance balance for the receiver baseband. The design consumes less than 2 mW and active area is 0.14 mm/sup 2/ in a 0.18-/spl mu/m digital CMOS technology. 相似文献
3.
This work presents a numerical analysis of the effects of thermal boundary conditions, fluid variable viscosity and wall conduction
on transient laminar natural convection of a high Prandtl number (Pr=4×104) fluid (Golden Syrup) in a cubical cavity. The simulations consider physical situations realizable at laboratory scale using
a cavity with Plexiglas walls of 1 cm of thickness, and inside dimension of L=20 cm. The initial Rayleigh (Ra) number is 106. The cavity is initially full of fluid at rest and at constant temperature (T
i
=45°C) higher than the temperature of the walls (T
w
=25°C). The time evolution of the flow patterns, the temperature contours, the mean temperature of the fluid and the Nusselt
number (Nu) of eight different cases of cooling are presented and analyzed. 相似文献
4.
Dosev D. Ytterdal T. Pallares J. Marsal L.F. Iniguez B. 《Electron Devices, IEEE Transactions on》2002,49(11):1979-1984
In this paper, we present a physically-based analytical model for n-channel nanocrystalline and microcrystalline thin-film transistors suitable for implementation in circuit simulators such as SPICE. The model is based on existing models for amorphous silicon thin film transistors, which have been extended to account for observed physical phenomena in nanocrystalline and microcrystalline thin film transistors. The proposed model has been verified for the most important regions of operation of the devices and has shown good agreement with experimental data. 相似文献
5.
Jose L. Muñoz Oscar Esparza Jordi Forné Esteve Pallares 《Telecommunication Systems》2009,41(3):229-241
A PKI (public key infrastructure) provides for a digital certificate that can identify an individual or an organization. However,
the existence of a certificate is a necessary but not sufficient evidence for its validity. The PKI needs to provide applications
that use certificates with the ability to validate, at the time of usage, that a certificate is still valid (not revoked).
One of the two standard protocols to check the revocation status of certificates is the Online Certificate Status Protocol
(OCSP). In this article, we propose an OCSP-based implementation that enhances the performance of standard OCSP. In particular,
we put special emphasis on those issues that affect security and performance when the validation service is deployed in a
real scenario. Finally, we provide experimental results that show that our implementation outperforms standard OCSP. 相似文献
6.
7.
We study the equilibrium properties of a liquid phase condensed at the nanoscale between the surfaces of a sharp crack in fused silica in a moist controlled atmosphere. The extension of the condensed phase along the fracture is measured by in situ atomic force microscopy phase imaging and it is shown to be determined by a critical distance between the opposite crack surfaces, which is an increasing function of humidity. The present technique is very promising for measuring the properties of confined liquids at the nanoscale as well as for modeling the physics and chemistry of slow crack propagation in glasses. 相似文献
8.
Dr. Pilar Formentin Moritz Tebbe Prof. Miguel A. Correa‐Duarte Pedro Granero Dr. Josep Ferré‐Borrull Prof. Rosana Alvarez Prof. Josep Pallares Prof. Andreas Fery Prof. Angel R. de Lera Prof. Lluis F. Marsal Prof. Ramón A. Alvarez‐Puebla 《Angewandte Chemie (International ed. in English)》2013,52(25):6459-6463
9.
Roger M. Pallares Dahlia D. An Gauthier J.-P. Deblonde Birgitta Kullgren Stacey S. Gauny Erin E. Jarvis Rebecca J. Abergel 《Chemical science》2021,12(14):5295
Transplutonium actinides are among the heaviest elements whose macroscale chemical properties can be experimentally tested. Being scarce and hazardous, their chemistry is rather unexplored, and they have traditionally been considered a rather homogeneous group, with most of their characteristics extrapolated from lanthanide surrogates. Newly emerged applications for these elements, combined with their persistent presence in nuclear waste, however, call for a better understanding of their behavior in complex living systems. In this work, we explored the biodistribution and excretion profiles of four transplutonium actinides (248Cm, 249Bk, 249Cf and 253Es) in a small animal model, and evaluated their in vivo sequestration and decorporation by two therapeutic chelators, diethylenetriamine pentaacetic acid and 3,4,3-LI(1,2-HOPO). Notably, the organ deposition patterns of those transplutonium actinides were element-dependent, particularly in the liver and skeleton, where lower atomic number radionuclides showed up to 7-fold larger liver/skeleton accumulation ratios. Nevertheless, the metal content in multiple organs was significantly decreased for all tested actinides, particularly in the liver, after administering the therapeutic agent 3,4,3-LI(1,2-HOPO) post-contamination. Lastly, the systematic comparison of the radionuclide biodistributions showed discernibly element-dependent organ depositions, which may provide insights into design rules for new bio-inspired chelating systems with high sequestration and separation performance.Transplutonium actinides are among the heaviest elements whose macroscale chemical properties can be experimentally tested. 相似文献
10.
Antonio Pallares‐Martín 《Mathematical Methods in the Applied Sciences》2016,39(18):5203-5215
We give some integrability conditions for the coefficients of a sequence of elliptic systems with varying coefficients in order to obtain the stability for homogenization. In the case of equations, it is well known that equi‐integrability and bound in L1 are enough for this purpose; however, this is based on the maximum principle, and then, it does not work for systems. Here, we use an extension of the Murat–Tartar div‐curl lemma because of M. Briane, J. Casado‐Díaz, and F. Murat in order to obtain the stability by homogenization for systems uniformly elliptic, with bounded coefficients in , with N the dimension of the space. We also show that a weaker ellipticity condition can be assumed, but then, we need a stronger integrability for the coefficients. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献