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81.
H. G. Bohlen R. Kalpakchieva W. von Oertzen T. N. Massey A. A. Ogloblin G. de Angelis M. Milin Ch. Schulz Tz. Kokalova C. Wheldon 《The European Physical Journal A - Hadrons and Nuclei》2007,31(3):279-302
The structure of 17C has been investigated using the three-neutron transfer reaction (12C,9C) on a 14C target at 231MeV incident energy, the reaction Q-value is Q
0 = - 46.930MeV. Eleven new states up to 16.3MeV excitation energy were identified. The same reaction has also been used on
a 12C target ( Q
0 = - 38.787MeV), and excited states in 15C up to 19MeV were observed. In 17C the three transferred neutrons populate (sd )3 configurations on the 14C core. The comparison of levels populated by the (12C,9C) reaction in 17C, 16C and 15C reveals a strong similarity of their properties. This concerns especially nine states in each of the three carbon isotopes,
which show practically the same excitation energies except a constant mean shift of +5.82MeV for 16C and +6.65MeV for 15C with respect to 17C. The triples of states from the three isotopes, which correspond to each other, have also similar widths and cross-section
ratios. It is concluded that the same (sd )3 structures are populated in the three carbon isotopes. The observed levels of 17C are also compared to the levels of 19O with known assignments and to shell model calculations, and their decay properties are discussed. 相似文献
82.
Victoria Sedwick Monique Massey TeAsia Codio A Bakarr Kanu 《International Journal for Ion Mobility Spectrometry》2017,20(3-4):75-86
An approach using method validation (MV) parameters, otherwise known as analytical figures of merit was combined with electrospray ionization high performance ion mobility spectrometry (ESI-HPIMS) to describe an approach for evaluating drugs and explosives analysis in the field. MV parameters such as reduced mobility (K o ), conditional reduced mobility (K c ), resolving power (R p ), theoretical plates (N), linearity, accuracy, precision, limit of detection (LOD), limit of quantitation (LOQ), repeatability, range, and reporting limit were investigated and developed for eleven drugs and six explosives. Our investigation estimated resolving power at 66 ± 0.64 for the ESI-HPIMS used. The LOD’s calculated ranged from 0.45–2.97 ng of material electrosprayed into the ESI-HPIMS. The LOQ’s calculated falls in the range 4.11–8.63 ng of material electrosprayed into the ESI-HPIMS. The key findings from this investigation were the following: K c proves to be a measure of the identity of an explosive or drug ion; a parameter that may be applied to help aid IMS devices when detecting drugs and explosives. MV parameters, especially, K c , introduced in this study is an effective parameter for establishing a unique identity of a drug or explosive. A control chart is an effective way to monitor the performance of an instrument and may be a useful tool for establishing reliability of confirmatory data in forensic investigations. MV parameters may be a reliable, accurate and unique identification marker for target drugs and explosives capable of differentiating these substances from false positive responses. 相似文献
83.
Multiprocessor scheduling: combining LPT and MULTIFIT 总被引:1,自引:0,他引:1
We consider the problem of scheduling a set of n independent jobs on m identical machines with the objective of minimizing the total finishing time. We combine the two most popular algorithms, LTP and MULTIFIT, to form a new one. MULTIFIT is well known to have better error bound than LPT with the price paid in running time. Although MULTIFIT provides a better error bound, in many cases LPT still can yield better results. This motivates the development of this new combined algorithm, which uses the result of LPT as the incumbent and then applies MULTIFIT with fewer iterations. The performance of this combined algorithm is better than that of LPT because it uses LPT as an incumbent. The error bound of this combined algorithm is never worse than that of MULTIFIT. For example, the error bound of implementing this combined algorithm to the two-processor problem is
, compared to the error bound of
in MULTIFIT. Empirical results of the comparison for schedules obtained by the combined algorithm, MULTIFIT and LPT are also provided. 相似文献
84.
85.
86.
87.
In this work, we introduce a new measure for the dispersion of the spectral scale of a Hermitian (self-adjoint) operator acting on a separable infinite-dimensional Hilbert space that we call spectral spread. Then, we obtain some submajorization inequalities involving the spectral spread of self-adjoint operators, that are related to Tao's inequalities for anti-diagonal blocks of positive operators, Kittaneh's commutator inequalities for positive operators and also related to the arithmetic–geometric mean inequality. In turn, these submajorization relations imply inequalities for unitarily invariant norms (in the compact case). 相似文献
88.
N Mirsaleh-Kohan AD Bass P Cloutier S Massey L Sanche 《The Journal of chemical physics》2012,136(23):235104
Desorption of anions stimulated by 1-18 eV electron impact on self-assembled monolayer (SAM) films of single DNA strands is measured as a function of film temperature (50-250 K). The SAMs, composed of 10 nucleotides, are dosed with O(2). The OH(-) desorption yields increase markedly with exposure to O(2) at 50 K and are further enhanced upon heating. In contrast, the desorption yields of O(-), attributable to dissociative electron attachment to trapped O(2) molecules decrease with heating. Irradiation of the DNA films prior to the deposition of O(2) shows that this surprising increase in OH(-) desorption, at elevated temperatures, arises from the reaction of O(2) with damaged DNA sites. These results thus appear to be a manifestation of the so-called "oxygen fixation" effect, well known in radiobiology. 相似文献
89.
90.
David B. Massey 《Proceedings of the American Mathematical Society》2006,134(7):2049-2060
We show how some of our recent results clarify the relationship between the Lê numbers and the cohomology of the Milnor fiber of a non-isolated hypersurface singularity. The Lê numbers are actually the ranks of the free Abelian groups--the Lê modules--appearing in a complex whose cohomology is that of the Milnor fiber. Moreover, the Milnor monodromy acts on the Lê module complex, and we describe the traces of these monodromy actions in terms of the topology of the critical locus.