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101.
102.
Thomas J. Ellis Jean-Pierre Raskin 《Journal of Infrared, Millimeter and Terahertz Waves》2002,23(9):1357-1369
A broadband vertical transition from coplanar waveguide (CPW)-to-microstrip modes is presented. The transition has a double resonance and can be tuned for very wide-band operation. The CPW-to-microstrip modes coupling technique is useful for the vertical integration of multi-layer millimeter-wave circuits, packaging and antenna feeding networks. A vertical transition has been fabricated on 100 μm silicon substrate for operation at W-band frequencies and shows less than 0.3 dB of insertion loss and better than 12 dB of return loss from 75 to 110 GHz. A 94 GHz CPW-fed microstrip antenna showing a 10-dB bandwidth of about 30 % has been built using the same transition technique. 相似文献
103.
104.
Equilibrium stress-strain relationships in uniaxial extension for high cis-1,4-polyisoprene (Shell IR 307) networks were obtained by extrapolation of relaxation measurements to infinite time through a BKZ constitutive equation. Three series of networks were investigated, each series being characterized by its polymer precursor molecular weight. Influence of crosslinking density was studied through varying amounts of dicumyl peroxide as crosslinking agent. These results were used to test Flory and Erman's recent molecular elasticity theory of imperfect networks with constraints on junctions. It was shown that this later theory treating entanglements as restrictions on junction fluctuations could be reasonably used to characterize network topology. A universal value of 0.50 for the interpenetration parameter I is confirmed and an interpretation of parameter ζ in terms of network inhomogeneity is tentatively given. 相似文献
105.
James?M.?Ma Samad?A.?Firdosy Richard?B.?Kaner Jean-Pierre?Fleurial Vilupanur?A.?RaviEmail author 《Journal of Materials Science》2014,49(3):1150-1156
Lanthanum telluride (La3?x Te4) is a state-of-the-art n-type high temperature thermoelectric material that behaves as a weak and brittle ceramic. Vickers microindentation hardness testing was explored as a rapid analysis technique to characterize the mechanical properties of this material. An indentation size effect was observed with hardness values ranging from 439 ± 31 kgf/mm2 (0.01 kgf/10 s contact time) to 335 ± 6 kgf/mm2 (0.5 kgf/10 s contact time). The Vickers indentation fracture toughness, K VIF, based on measurements of crack lengths emanating from the corners of the Vickers indents was 0.70 ± 0.06 MPa m1/2. 相似文献
106.
Guillermo A. Oliveira Udry Laura Tiessler-Sala Eva Pugliese Agathe Urvoas Zakaria Halime Jean-Didier Marchal Jean-Pierre Mahy Rmy Ricoux 《International journal of molecular sciences》2022,23(23)
The covalent insertion of a cobalt heme into the cavity of an artificial protein named alpha Rep (αRep) leads to an artificial cobalt hemoprotein that is active as a catalyst not only for the photo-induced production of H2, but also for the reduction of CO2 in a neutral aqueous solution. This new artificial metalloenzyme has been purified and characterized by Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS), circular dichroism, and UltraViolet–Visible spectroscopy. Using theoretical experiments, the structure of this biohybrid and the positioning of the residues near the metal complex were examined, which made it possible to complete the coordination of the cobalt ion by an axial glutamine Gln283 ligand. While the Co(III)–porphyrin catalyst alone showed weak catalytic activity for both reactions, 10 times more H2 and four times more CO2 were produced when the Co(III)–porphyrin complex was buried in the hydrophobic cavity of the protein. This study thus provides a solid basis for further improvement of these biohybrids using well-designed modifications of the second and outer coordination sphere by site-directed mutagenesis of the host protein. 相似文献
107.
We present a numerical study of a neural tree learning algorithm, the “triolearning≓ strategy. We study the behaviour of the
algorithm as a function of the size of the training set. The results show that a limited number of examples can be used to
estimate both the network performance and the network complexity that would result from running the algorithm on a large data
set. 相似文献
108.
109.
Chi-Woo Lee Dimitri Lederer Aryan Afzalian Ran Yan Nima Dehdashti Weize Xiong Jean-Pierre Colinge 《Solid-state electronics》2008,52(11):1815-1820
The performances of accumulation-mode and inversion-mode multigate FETs are compared. The influence of gate underlap on the electrical properties is analyzed. Both simulation results and experimental data show that in a device with gate underlap, accumulation-mode devices have a higher current drive, lower source and drain resistance and less process variability than inversion-mode FETs. 相似文献
110.
Jean-Pierre Delahaye 《电信纪事》1996,51(1-2):19-26
This paper presents an overview of the implementation of a difference-set cyclic code (1057,813,34). It is easy to achieve coding and decoding circuits. The decoding lays on the analysis of the composite remainder Rc (x) and the use of a decoding matrix of 33 Boolean equations. The error-correcting algorithm has been improved, so the difference-set cyclic code (1057,813,34) can correct up to 26 random errors instead of the 16 previous random errors found by the theory. Moreover, 3 decoding algorithms have been simulated and allow the comparison of their respective efficiency. The hardware achievement is quite easy because the necessary logical elements such as shift delay registers, positive-and gates, positive-or gates, positive-exclusive-or gates exist as a set of libraries. 相似文献