901 resultados para Figure and figurative
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The design of a Gilbert Cell Mixer and a low noise amplifier (LNA), using GaAs PHEMT technology is presented. The compatibility is shown for co-integration of both block on the same chip, to form a high performance 1.9 GHz receiver front end. The designed LNA shows 9.23 dB gain and 2.01 dB noise figure (NF). The mixer is designed to operate at RF=1.9 GHz, LO=2.0 GHz and IF=100 MHz with a gain of 14.3 dB and single sideband noise figure (SSB NF) of 9.6 dB. The mixer presents a bandwith of 8 GHz.
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The controlled growth of SnO2 nanoparticles for gas sensor applications is reported by these authors. Nb2O5 additive is used to control nucleation and growth of the SnO2 (see Figure), which is synthesized by the polymeric precursor method. Preliminary gas sensing measurements are performed and it is demonstrated that the response time of the Nb2O5-doped SnO2 is faster than that of the undoped material.
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We report measurements of the nonlinear (NL) refractive index n(2) of lead-germanium films (LGFs) containing Cu and Cu(2)O nanoparticles (NPs). The thermally managed eclipse Z-scan technique with 150 fs pulses from a laser operating at 800 nm was used. The NL refractive index measured, n(2)=6.3x10(-12) cm(2)/W has electronic origin and the NL absorption coefficient alpha(2) is smaller than 660 cm/GW. The figure of merit n(2)/lambda alpha(2) is enhanced by more than two orders of magnitude in comparison with the result for the LGFs without the copper based NPs. (C) 2008 American Institute of Physics.
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The design of a Gilbert Cell Mixer and a low noise amplifier (LNA), using GaAs PHEMT technology is presented. The compatibility is shown for co-integration of both block on the same chip, to form a high performance 1.9 GHz receiver front-end. The designed LNA shows 9.23 dB gain and 2.01 dB noise figure (NF). The mixer is designed to operate at RF=1.9 GHz, LO=2.0 GHz and IF=100 MHz with a gain of 14.3 dB and single sideband noise figure (SSB NF) of 9.6 dB. The mixer presents a bandwith of 8 GHz.
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Nonlinear (NL) optical properties of antimony oxide based glasses (AG) were characterized for excitation wavelengths from 800 to 1600 m. The NL refractive indices, n2, and the two-photon absorption (TPA) coefficient, β, have been evaluated using the Z-scan technique. Values of n2≈ 10-15 - 10-14 cm2/W of electronic origin were measured and negligible TPA coefficients (β < 0.003 cm/GW) were determined. The response time of the nonlinearity is faster than 100 fs as determined using the Kerr shutter technique. The figure-of-merit usually considered for all-optical switching, T = 2βλ/n2 , indicates that AG are very good materials for ultrafast switches at telecom wavelengths. © 2007 IEEE.
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Includes bibliography
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Foreword Throughout the preparatory process for the World Summit on Sustainable Development and at the Summit itself, which was held in Johannesburg, South Africa, from 26 August to 4 September 2002, discussions were dominated by one central concern: the need to define and reach consensus on concrete, quantitative goals, with fixed deadlines for implementation, which were to supplement the Millennium Development Goals and facilitate progress towards an effective transition to sustainable development. Participants at the Summit explicitly affirmed the need, as a matter of urgency, to identify the financial and technical resources whereby sustainable development would become a reality and benefit directly and particularly rural and urban communities in the developing countries. The document we are now presenting is the outcome of extensive discussions held at a high-level forum during the Johannesburg Summit. Led by representatives of the Government of Mexico, the Economic Commission for Latin America and the Caribbean (ECLAC), the United Nations Development Programme (UNDP) and the Andean Development Corporation, those discussions were based on the ECLAC/UNDP study entitled Financing for sustainable development in Latin America and the Caribbean: from Monterrey to Johannesburg, which considers the opportunities and challenges for improving prospects for investment and financing for sustainable development and underscores the need to establish a new balance between the market economy and public interest through joint public/private initiatives that combine market innovation, social responsibility and appropriate regulations. Other eminent persons attending the event included heads of State, such as Gustavo Noboa, then President of Ecuador; Enrique V. Iglesias, President of the Inter-American Development Bank (IDB); José María Figueres, Managing Director of the Global Agenda of the World Economic Forum and former President of Costa Rica; and Gro Harlem Brundtland, the legendary figure who pioneered sustainable development. Valuable contributions to the discussions were made by Yolanda Kakabadse, President of the World Conservation Union; Xóchitl Gálvez Ruiz, head of the Unit for the Development of Indigenous Peoples of the Office of the President of Mexico; Cecilia López, former Minister for the Environment of Colombia; and Juan Carlos Maqueda, then Vice President of Argentina. The views emerging from the forum as set forth in this document are designed to facilitate and promote application of the Plan of Implementation of the World Summit on Sustainable Development within the framework of the Millennium Development Goals and the commitments assumed at the International Conference on Financing for Development, which was held in Monterrey, Mexico. We also aspire to continue moving forward with the adoption of measures and policies to increase investment and financing for sustainable development as well as to foster partnerships between the public and private sectors and nongovernmental organizations. We recognize, in this context, the importance of strengthening and improving public and private institutions in order to meet the operational needs associated with the effort to achieve the Millennium Development Goals and pursue the Plan of Implementation formulated in Johannesburg. We trust that this document will contribute to in-depth discussions on the application of the Plan of Implementation in the relevant forums, in particular the United Nations Commission on Sustainable Development. The Plan of Implementation of the World Summit on Sustainable Development opens up new opportunities for Latin America and the Caribbean to renew and revive their own regional agenda -with emphasis on global and especially regional public goods- and to interweave it more cohesively with the global agenda in order to promote the common interests of Latin America and the Caribbean more forcefully in international development forums. The regional agenda and the global agenda cannot be separated in a contrived manner; indeed, to an increasing degree, what we are witnessing are global environmental processes which call for action at the local level. The achievement of sustainable development in Latin America and the Caribbean, where the necessary economic, social, environmental and geopolitical conditions are combined, requires a subtle balance between the market economy, the State and the citizen. Such a balance will result in the consolidation of democratic governance in the service of human development. VICENTE FOX President of Mexico JOSÉ ANTONIO OCAMPO Executive Secretary, Economic Commission for Latin America and the Caribbean (ECLAC) ELENA MARTÍNEZ Assistant Aministrator and Regional Director for Latin America and the Caribbean of the United Nations Development Programme (UNDP) ENRIQUE GARCÍA Executive President, Andean Development Corporation (ADC)""
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(Figure Presented) Mixed micelles of cetyltrimethylammonium bromide (CTABr) or dodecyltrimethylammonium bromide (DTABr) and the α-nucleophile, lauryl hydroxamic acid (LHA) accelerate dephosphorylation of bis(2,4-dinitrophenyl) phosphate (BDNPP) over the pH range 4-10. With a 0.1 mole fraction of LHA in DTABr or CTABr, dephosphorylation of BDNPP is approximately 10 4-fold faster than its spontaneous hydrolysis, and monoanionic LHA - is the reactive species. The results are consistent with a mechanism involving concurrent nucleophilic attack by hydroxamate ion (i) on the aromatic carbon, giving an intermediate that decomposes to undecylamine and 2,4-dinitrophenol, and (ii) at phosphorus, giving an unstable intermediate that undergoes a Lossen rearrangement yielding a series of derivatives including N,N-dialkylurea, undecylamine, undecyl isocyanate, and carbamyl hydroxamate. © 2009 American Chemical Society.
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Includes bibliography
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Incluye Bibliografía
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A search for supersymmetry in final states with jets and missing transverse energy is performed in pp collisions at a centre-of-mass energy of s=7 TeV. The data sample corresponds to an integrated luminosity of 4.98 fb-1 collected by the CMS experiment at the LHC. In this search, a dimensionless kinematic variable, α T, is used as the main discriminator between events with genuine and misreconstructed missing transverse energy. The search is performed in a signal region that is binned in the scalar sum of the transverse energy of jets and the number of jets identified as originating from a bottom quark. No excess of events over the standard model expectation is found. Exclusion limits are set in the parameter space of the constrained minimal supersymmetric extension of the standard model, and also in simplified models, with a special emphasis on compressed spectra and third-generation scenarios.[Figure not available: see fulltext.] © 2013 CERN for the benefit of the CMS Collaboration.
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Results are presented from a search for the pair-production of heavy quarks, QQ̄, that decay exclusively into a top quark and a W or Z boson. The search is performed using a sample of proton-proton collisions at √s = 7 TeV corresponding to an integrated luminosity of 5.0 fb-1, collected by the Compact Muon Solenoid experiment. The signal region is defined using a sample of events containing one electron or muon, missing transverse momentum, and at least four jets with large transverse momenta, where one jet is likely to originate from the decay of a bottom quark. No significant excess of events is observed with respect to the standard model expectations. Assuming a strong pair-production mechanism, quark masses below 675 (625) GeV decaying into tW (tZ) are excluded at the 95 % confidence level.[Figure not available: see fulltext.] © 2013 CERN for the benefit of the CMS collaboration.