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121.
Isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) was applied to the certification of Pb in four levels of NIST blood SRM, 955a. This standard reference material (SRM) represents a significant improvement over the previous blood reference material and will greatly aid method development. The lowest level, 47.76 ng/g Pb was determined with analysis uncertainty (95% CI, ID-ICP-MS uncertainties) of less than 1% and the highest level, 517.9 ng/g Pb to 0.3%. Uncertainty in the lowest level was due to sample inhomogeneity and variability in the analytical blank as the RSD on ratio measurements was typically better than 0.2%. Properly applied isotope dilution coupled with careful isotope ratio measurements on the ICP-MS offers precision and accuracy for blood Pb analyses beyond what is currently obtainable with routine methods. 相似文献
122.
N.
zkan A. St. J. Murphy R. N. Boyd A. L. Cole M. Famiano R. T. Güray M. Howard L.
ahin J. J. ZachR. deHaan J. Grres M. C. WiescherM. S. IslamT. Rauscher 《Nuclear Physics A》2002,710(3-4)
Total cross section measurements for the 102Pd(p, γ)103Ag and 116Sn(p, γ)117Sb reactions have been performed in the proton energy range 2.6 to 4.25 MeV, and for the 112Sn(α, γ)116Te reaction over the alpha beam energy range 7.0 to 10.5 MeV. An activation technique was used in which gamma rays from decays of the reaction products were detected off-line by two hyper-pure germanium detectors in a low background environment. Where possible, reaction rates are derived and the results compared to those of calculations generated by the NON-SMOKER and the MOST statistical model codes so as to judge their applicability for describing the cross sections needed for network calculations of nucleosynthesis in explosive astrophysical environments via the γ- and rp-processes. 相似文献
123.
Gerard J. Murphy 《Integral Equations and Operator Theory》1996,24(3):298-319
The concept of a twisted crossed product associated to a non-classical C*-dynamical system is introduced and studied. The relationship between a covariant projective representation of the system and the corresponding induced representation of the twisted crossed product is investigated, particularly from the point of view of determining when the induced representation is faithful. Conditions are given on the C*-dynamical system that ensure nuclearity, simplicity or primeness of the twisted crossed product. 相似文献
124.
In this paper we give an approximate probability distribution for the maximum order complexity of a random binary sequence. This enables the development of statistical tests based on maximum order complexity for the testing of a binary sequence generator. These tests are analogous to those based on linear complexity. 相似文献
125.
A. Bresson Y. Bidel P. Bouyer B. Leone E. Murphy P. Silvestrin 《Applied physics. B, Lasers and optics》2006,84(4):545-550
This paper is an introduction to the following articles in the scope of quantum mechanics for space study initiated by ESA and lead by ONERA. The context of quantum mechanics for space is summarised, and the fields under development are briefly introduced. Technological applications of quantum mechanics in space are explored and some tests of quantum mechanics are outlined. We also give a brief presentation of the opto-electronic section of the European Space Agency, and the technology development activities it carries out, with particular emphasis on those activities related to the topics of interest of the quantum mechanics in space workshop. As an example, a summary of two ESA studies on gravity gradiometry and their relevance to the field of atomic interferometry is given. In view of the scientific requirements, derived for both Earth observation and planetology for future space missions, atom interferometry shows promise and may provide an advantage over currently available accelerometer and inertial sensor systems. PACS 04.25.Nx; 04.80.Cc; 07.60.Ly; 95.30.Sf 相似文献
126.
Hanif D. Sherali Allen L. Soyster Frederic H. Murphy Suvrajeet Sen 《European Journal of Operational Research》1982,11(4):349-360
This paper concerns methods for discretizing and approximating the annual load duration curve in the context of a linear programming model and its interpretation in electric utility expansion planning. The emphasis is upon the interpretation of the linear programming dual variables and their relationship with classical results of peak load pricing. In particular, for capacity planning in which one can choose from a diverse number of technological alternatives, we support the work of Wenders by precisely characterizing how off-peak periods bear partial responsibility of the capacity cost. 相似文献
127.
K. E. Hardenstine G. V. S. Henderson L. H. Sperling C. J. Murphy G. E. Manser 《Journal of Polymer Science.Polymer Physics》1985,23(8):1597-1609
Two crystal modifications have been found for poly(3,3-bisethoxymethyl oxetane) [poly- (BEMO)] by wide-angle x-ray powder diffraction and differential scanning calorimetry, while only one modification has been found for poly(3,3-bisazidomethyl oxetane) [poly(BAMO)]. Melting temperatures for the two polymers were nearly the same, varying from about 70 to about 90°C depending on the thermal treatment; higher crystallization temperatures resulted in higher melting temperatures. The equilibrium melting temperature T was found to be 125 and 128°C for poly(BEMO) and poly(BAMO), respectively, by using the Hoffman-Weeks extrapolation procedure. Measurement of the melting-point depression of Poly(BEMO) and poly(BAMO) in dibutyl phthalate yielded enthalpy of fusion values of 2.25 and 12.8 kcal/mol, respectively. The percent crystallinity for poly(BEMO) and poly(BAMO), respectively, was calculated to be 55-60 and 13-30% based on DSC and x-ray analysis. 相似文献
128.
The theoretical ground-state radial distribution function of liquid 4He appears to depend much more sensitively on the range of the assumed two-body potential than on its depth. Fairly good agreement with experiment is obtained by using realistic pair potentials. 相似文献
129.
130.