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41.
This paper describes the development of a generic platform for enhanced, integrated optic sensors based on fluorescence detection. The platform employs a novel optical configuration in order to achieve enhanced performance and has inherent multianalyte detection capability. The sensor element comprises a multimode ridge waveguide that has been patterned with an analyte-sensitive fluorescent spot, which is excited directly using a LED. The platform was applied to the detection of gaseous oxygen as a proof of principle. The sol-gel-derived sensor spots were doped with an oxygen-sensitive fluorescent dichlororuthenium dye complex and intensity-based calibration data were generated from the oxygen-dependent waveguide output. The sensor achieved a LOD of 0.62% and a resolution of less than 0.96% gaseous oxygen, which compares favourably with a similar, recently reported system. This device highlights the combination of inexpensive rapid prototyping techniques and a dedicated sensor enhancement strategy that together facilitate the production of an effective prototype sensor platform.  相似文献   
42.
Annals of the Institute of Statistical Mathematics - In attempting to find the most practical and efficient nonparametric rank test in the two-sample problem of testing for equality of populations,...  相似文献   
43.
44.
Activity coefficients of hydrochloric acid in mixed solutions of manganous chloride at twelve ionic strengths, from 0.1 to 5.0 mole-kg–1, were obtained from emf measurements of cells without liquid junction at five temperatures from 5 to 45°C. The data were interpreted in terms of the simple and convenient Pitzer treatment. Activity coefficients for manganous chloride in the mixtures were also derived using Pitzer's equations. Hydrochloric acid follows Harned's rule fromI=0.1 to 3.0 mole-kg–1, as concluded by Downes, whereas quadratic terms are warranted fromI=3.5 to 5.0 mole-kg–1. Contrary to Downes' conclusion, Harned's rule clearly does not hold true for manganous chloride at most ionic strengths.  相似文献   
45.
The spontaneous loss of charge by black holes due to particle emission is discussed. For large black holes (more massive than 1017 g) the process is shown to be governed by a Schwinger type formula. For smaller black holes the method of calculating the process is described and asymptotic forms for scattering and superradiant coefficients given.  相似文献   
46.
We present a new family of self-dual positive definite metrics which are asymptotic to Euclidean space modulo identifications under discrete subgroups of O(4). these solutions contain 3τ ? 3 parameters where τ is the signature. We show that a fully general self-dual solution with these boundary conditions should have this number of parameters.  相似文献   
47.
Camera luminometer for use with luminescent assays   总被引:1,自引:0,他引:1  
  相似文献   
48.
We determine the dielectron widths of the Gamma(1S), Gamma(2S), and Gamma(3S) resonances with better than 2% precision by integrating the cross section of e+e- -->Gamma over the e+e- center-of-mass energy. Using e+e- energy scans of the Gamma resonances at the Cornell Electron Storage Ring and measuring Gamma production with the CLEO detector, we find dielectron widths of 1.252+/-0.004(sigma(stat))+/-0.019(sigma(syst)) keV, 0.581+/-0.004+/-0.009 keV, and 0.413+/-0.004+/-0.006 keV for the Gamma(1S), Gamma(2S), and Gamma(3S), respectively.  相似文献   
49.
We observe signals for the decays psi(3770) --> XJ/psi from data acquired with the CLEO detector operating at the CESR e+ e- collider with square root of s = 3773 MeV. We measure the following branching fractions Beta(psi(3770) --> XJ/psi and significances: (189 +/- 20 +/- 20) x 10(-5) (11.6sigma) for X = pi+ pi-, (80 +/- 25 +/- 16) x 10(-5) (3.4sigma) for X = pi0 pi0, and (87 +/- 33 +/- 22) x 10(-5) (3.5sigma) for X = eta, where the errors are statistical and systematic, respectively. The radiative return process e+ e- --> gamma psi(2S) populates the same event sample and is used to measure Gamma ee[psi(2S)] = (2.54 +/- 0.03 +/- 0.11) keV.  相似文献   
50.
We present the first experimental limits on high-q2 contributions to charmless semileptonic decays of the form expected from the weak annihilation (WA) decay mechanism. Such contributions could bias determinations of /Vub/ from inclusive measurements of B-->Xulupsilon. Using a wide range of models based on available theoretical input we set a limit of GammaWA/Gammab-->u<7.4% (90% confidence level) on the WA fraction, and assess the impact on previous inclusive determinations of /Vub/.  相似文献   
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