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11.
A novel cascaded charge-sharing technique is presented in content-addressable memories (CAMs), which not only effectively reduces the match-line (ML) power by using a pre-select circuit, but also realizes a high search speed. Pre-layout simulation results show a 75.9% energy-delay-product (EDP) reduction of the MLs over the traditional precharge-high ML scheme and 41.3% over the segmented ML method. Based on this technique, a test-chip of 64-word × 144-bit ternary CAM (TCAM) is implemented using a 0.18-μm 1.8-V CMOS process, achieving an 1.0 ns search delay and 4.81 fJ/bit/search for the MLs. 相似文献
12.
F. A. Lops F. Maddalena S. Solimini 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2001,18(6):639
The paper deals with the problem of minimizing a free discontinuity functional under Dirichlet boundary conditions. An existence result was known so far for C1(∂Ω) boundary data û. We show here that the same result holds for ûC0,μ(∂Ω) if
and it cannot be extended to cover the case
. The proof is based on some geometric measure theoretic properties, in part introduced here, which are proved a priori to hold for all the possible minimizers. 相似文献
13.
Navin A Anthony DW Aumann T Baumann T Bazin D Blumenfeld Y Brown BA Glasmacher T Hansen PG Ibbotson RW Lofy PA Maddalena V Miller K Nakamura T Pritychenko BV Sherrill BM Spears E Steiner M Tostevin JA Yurkon J Wagner A 《Physical review letters》2000,84(2):266-269
We derive the formalism to obtain spatial distributions of collisional correlation times for macroscopic particles undergoing granular flow from pulsed gradient spin echo nuclear magnetic resonance diffusion data. This is demonstrated with an example of axial motion in the shear flow regime of a 3D granular flow in a horizontal rotating cylinder at one rotation rate. 相似文献
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Antonio Roviello Fabio Borbone Antonio Carella Rosita Diana Giuseppina Roviello Barbara Panunzi Antonio Ambrosio Pasqualino Maddalena 《Journal of polymer science. Part A, Polymer chemistry》2009,47(10):2677-2689
The synthesis and the chemical physical characterization of new photoluminescent (PL) chromophores and polymers are reported. Chromophores (oligo‐PPV symmetric derivatives ending with amino groups) are strong blue emitters with a PL quantum yield of ~70% in dioxane solution. They have been used to prepare polyamides by reaction with aliphatic acyl dichlorides in which emitting and non emitting units are alternated. PL properties of the synthesized polyamides have been evaluated in solution and reveal a strong blue emission (PL quantum yield ~60%), To increase the solubility of these systems, oligomers have been purposely prepared and then characterized. They show a peculiar white emission when excited in DMF solution; to get insight into this interesting behavior, asymmetric monoacetylated chromophores have been prepared as model compounds for the chromophoric end groups of the polyamide chains. The emission spectra of these compounds reveal a broad excimeric yellow emission which is responsible, along with the blue emission of the inner chromophoric units, of the overall white emission of the oligomers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2677–2689, 2009 相似文献
16.
Dmitry S. Perekalin Valentin V. Novikov Maddalena Corsini Alexander R. Kudinov 《Journal of organometallic chemistry》2010,695(8):1200-1204
The reactions of benzo-15-crown-5 and dibenzo-18-crown-6 with 1 equiv. of [(mes)Ru(MeNO2)3]2+ (mes = 1,3,5-C6H3Me3) give the mononuclear complexes [(mes)Ru(η6-benzo-15-crown-5)]2+ (1) and [(mes)Ru(η6-dibenzo-18-crown-6)]2+ (2) in 50% yield. Similar reaction with 2 equiv. of [(mes)Ru(MeNO2)3]2+ produces the dinuclear complex [(μ-η6:η6-dibenzo-18-crown-6)Ru2(mes)2]4+ (3) in 96% yield as a 2:3 mixture of cis- and trans-isomers. Structures of 2(OTf)2 and trans-3(OTf)4 were confirmed by X-ray diffraction. The NMR titration showed that mononuclear dications 1 and 2 bind Na+ ion less effective (Ka = 600 and 250 M-1) than free benzo-15-crown-5 and dibenzo-18-crown-6 (Ka = 2 × 105 and 5 × 106 M−1). The dinuclear tetracation 3 does not bind Na+ within measurable limits of NMR titration method. The electrochemical behaviour of complexes 1-3 was studied in propylene carbonate solution. They exhibit a partially chemically reversible Ru(II)/Ru(I) reduction, which in the case of the dinuclear complex 3 proceeds through two slightly separated steps. The redox activity of the complexes is substantially unaffected by the presence of sodium ion. 相似文献
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Bi-ideals in regular semigroups and in orthogroups 总被引:4,自引:0,他引:4
Maria Maddalena Miccoli 《Acta Mathematica Hungarica》1986,48(1-2):3-6
20.
Probing the Coordinative Unsaturation and Local Environment of Ti3+ Sites in an Activated High‐Yield Ziegler–Natta Catalyst
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Elena Morra Prof. Elio Giamello Prof. Sabine Van Doorslaer Giuseppe Antinucci Dr. Maddalena D'Amore Prof. Vincenzo Busico Prof. Mario Chiesa 《Angewandte Chemie (International ed. in English)》2015,54(16):4857-4860
The typical activation of a fourth generation Ziegler–Natta catalyst TiCl4/MgCl2/phthalate with triethyl aluminum generates Ti3+ centers that are investigated by multi‐frequency continuous wave and pulse EPR methods. Two families of isolated, molecule‐like Ti3+ species have been identified. A comparison of the experimentally derived g tensors and 35,37Cl hyperfine and nuclear‐quadrupole tensors with DFT‐computed values suggests that the dominant EPR‐active Ti3+ species is located on MgCl2(110) surfaces (or equivalent MgCl2 terminations with tetra‐coordinated Mg). O2 reactivity tests show that a fraction of these Ti sites is chemically accessible, an important result in view of the search for the true catalyst active site in olefin polymerization. 相似文献