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Same Wavelength (same + wavelength)
Selected AbstractsMinocycline-Based Europium(III) Chelate Complexes: Synthesis, Luminescent Properties, and Labeling to StreptavidinHELVETICA CHIMICA ACTA, Issue 11 2009Takuya Nishioka Abstract Two chelate ligands for europium(III) having minocycline (=(4S,4aS,5aR,12aS)-4,7-bis(dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,10,12,12a-tetrahydroxy-1,11-dioxonaphthacene-2-carboxamide; 5) as a VIS-light-absorbing group were synthesized as possible VIS-light-excitable stable Eu3+ complexes for protein labeling. The 9-amino derivative 7 of minocycline was treated with H6TTHA (=triethylenetetraminehexaacetic acid=3,6,9,12-tetrakis(carboxymethyl)-3,6,9,12-tetraazatetradecanedioic acid) or H5DTPA (=diethylenetriaminepentaacetic acid=N,N -bis{2-[bis(carboxymethyl)amino]ethyl}glycine) to link the polycarboxylic acids to minocycline. One of the Eu3+ chelates, [Eu3+(minocycline-TTHA)] (13), is moderately luminescent in H2O by excitation at 395,nm, whereas [Eu3+(minocycline-DTPA)] (9) was not luminescent by excitation at the same wavelength. The luminescence and the excitation spectra of [Eu3+(minocycline-TTHA)] (13) showed that, different from other luminescent EuIII chelate complexes, the emission at 615,nm is caused via direct excitation of the Eu3+ ion, and the chelate ligand is not involved in the excitation of Eu3+. However, the ligand seems to act for the prevention of quenching of the Eu3+ emission by H2O. The fact that the excitation spectrum of [Eu3+(minocycline-TTHA)] is almost identical with the absorption spectrum of Eu3+ aqua ion supports such an excitation mechanism. The high stability of the complexes of [Eu3+(minocycline-DTPA)] (9) and [Eu3+(minocycline-TTHA)] (13) was confirmed by UV-absorption semi-quantitative titrations of H4(minocycline-DTPA) (8) and H5(minocycline-TTHA) (12) with Eu3+. The titrations suggested also that an 1,:,1 ligand Eu3+ complex is formed from 12, whereas an 1,:,2 complex was formed from 8 minocycline-DTPA. The H5(minocycline-TTHA) (12) was successfully conjugated to streptavidin (SA) (Scheme,5), and thus the applicability of the corresponding Eu3+ complex to label a protein was established. [source] Blocking performance of fixed-paths least-congestion routing in multifibre WDM networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 2-3 2002Ling Li Abstract Wavelength-routed all-optical networks have been receiving significant attention for high-capacity transport applications. Good routing and wavelength assignment (RWA) algorithms are critically important in order to improve the performance of wavelength-routed WDM networks. Multifibre WDM networks, in which each link consists of multiple fibres and each fibre carries information on multiple wavelengths, offer the advantage of reducing the effect of the wavelength continuity constraint without using wavelength converters. A wavelength that cannot continue on the next hop on the same fibre can be switched to another fibre using an optical cross-connect (OXC) if the same wavelength is free on one of the other fibres. However, the cost of a multifibre network is likely to be higher than a single-fibre network with the same capacity, because more amplifiers and multiplexers/demultiplexers may be required. The design goal of a multifibre network is to achieve a high network performance with the minimum number of fibres. In this paper, we study the blocking performance of fixed-paths least-congestion (FPLC) routing in multifibre WDM networks. A new analytical model with the consideration of link-load correlation is developed to evaluate the blocking performance of the FPLC routing. The analytical model is a generalized model that can be used in both regular (e.g. mesh-torus) and irregular (e.g. NSFnet) networks. It is shown that the analytical results closely match the simulation results, which indicate that the model is adequate in analytically predicting the performance of the FPLC routing in different networks. Two FPLC routing algorithms, wavelength trunk (WT)-based FPLC and lightpath (LP)-based FPLC, are developed and studied. Our analytical and simulation results show that the LP-based FPLC routing algorithm can use multiple fibres more efficiently than the WT-based FPLC and the alternate path routing. In both the mesh-torus and NSFnet networks, limited number of fibres is sufficient to guarantee high network performance. Copyright © 2002 John Wiley & Sons, Ltd. [source] Chiral analysis of milnacipran by a nonchiral HPLC , circular dichroism: Improvement of the linearity of dichroic response by temperature controlJOURNAL OF SEPARATION SCIENCE, JSS, Issue 16-17 2008Marie Lecoeur-Lorin Abstract The determination of the enantiomeric excess (e.e.) of a basic drug has been investigated in LC using a nonchiral stationary phase and a circular dichroism (CD) detector in order to avoid expensive chiral columns. The CD detector records both dichroic (,,) and UV (,) signals at the same wavelength and calculates the anisotropy factor (g = ,,/,), which is linearly related to the e.e. The enantiomeric and chemical composition of a chiral drug can be simultaneously determined on a nonchiral HPLC support. However, the g factor from the CD signal is temperature dependent. Indeed, the temperature has an influence on the stability of the CD signal and the linear regression between g factor and the e.e. of 1R,2S -enantiomer. So, a decrease in temperature gives rise to an improvement of the above-mentioned linearity correlation. After optimization of chromatographic parameters (porous graphitic carbon-based column, methanol/ phosphate buffer as mobile phase) and selection of CD wavelength, a linear regression of g factor versus e.e. of 1R,2S -enantiomer was obtained at temperature-controlled CD detection and an LOQ of 94% was found. The enantiomeric composition of milnacipran was determined with good accuracy. [source] Optimizing the internal quantum efficiency of GaInN SQW structures for green light emittersPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2006D. Fuhrmann Abstract GaxIn1,xN/GaN single quantum well (QW) structures emitting in the range of 450 nm to 620 nm have been grown by MOVPE. Temperature and excitation power dependent photoluminescence (PL) was used to determine the internal quantum efficiency (IQE) for these structures. For the blue emitting QWs high IQE values on the order of 60% were achieved. Due to a reduced growth temperature, reduced growth rate and increased V/III ratio we obtained QWs with good morphology and high In content above 25%. Thinner QWs with high In content showed a clear improvement of IQE compared to QW-structures with larger thickness but smaller In-content emitting at the same wavelength. Between ,peak = 460 nm and 530 nm we observed a slight reduction in IQE with values of 58% at 490 nm and 40% at 525 nm. But towards ,peak = 620 nm IQE decreased due to the electric field induced separation of the electron and hole wavefunction down to 1%. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The dependence of cirrus infrared radiative properties on ice crystal geometry and shape of the size-distribution functionTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 607 2005Anthony J. Baran Abstract The concept of an effective diameter is often used to describe the radiative properties of cirrus, and is commonly applied in the retrieval of cirrus microphysical and/or macrophysical properties. In this paper the applicability of an effective-diameter concept at thermal wavelengths (4.0,30 µm) is further investigated. It is shown that at a wavelength of 8.2 µm the concept begins to break down for small ice crystal effective diameters (,25 µm) and has completely broken down beyond a wavelength of 20 µm. At wavelengths in the far infrared (20,30 µm) the potential impact of ice crystal geometry and assumed size-distribution shape on brightness-temperature measurements is quantified. It is found that the brightness-temperature difference at a wavelength of 25 µm due to two different populations of ice crystal shapes, but with both populations having the same effective diameter and size-distribution shape, is ,5 K. However, if both populations have the same ice crystal shape and effective diameter but different size-distribution shapes, then the brightness-temperature difference is about ,9 K at the same wavelength. The impact of size-distribution shape on the brightness-temperature difference is almost twice as great as that of crystal shape. Given that there is sensitivity to the shape of the size-distribution function at far-infrared wavelengths, the potential for retrieving size-distribution shape using far-infrared brightness-temperature measurements is also investigated. The implications of these findings are that the concept of an effective diameter cannot be generally applied at infrared wavelengths unless a priori information is known about the shape of the size-distribution function. Copyright © 2005 Royal Meteorological Society [source] Measurement of memory of colorCOLOR RESEARCH & APPLICATION, Issue 4 2002H. H. Seliger Abstract Colors produced by monochromatic wavelengths of light viewed in isolation have been used as the only visual variables in short-term delayed matching (DM) and long-term recall (LTR) protocols to quantify three types of color memory in individuals with normal color vision. Measurements were normally distributed, so that color memories of individuals could be compared in terms of means and standard deviations. The variance of LTR of colors of familiar objects is shown to be separable into two portions, one due to "preferred colors" and the other due to individuals' precisions of matching. The wavelength dependence of DM exhibited minima of standard deviations at the same wavelengths as those reported for color discrimination measured by bipartite wavelength matching, and these wavelengths were shown to occur at the wavelengths of the intersections of cone spectral sensitivities. In an intermediate "green" region of relatively constant color discrimination, it was possible to combine DM measurements for different wavelengths for statistical analysis. The standard deviations of DM for individuals of a healthy population were normally distributed, providing a 95% upper confidence limit for identifying individuals with possible short-term memory impairment. Preliminary measurements of standard deviations of DM for delay times of , 1 s were consistent with a proposed rapidly decaying color imagery memory. © 2002 Wiley Periodicals, Inc. Col Res Appl, 27, 233,242, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10067 [source] | ||||||||||