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151.
Neelam Goyal Paru J. Purohit A. G. Page 《Fresenius' Journal of Analytical Chemistry》1998,361(5):429-432
Atomization processes for uranium in aqueous media and in the presence of a plutonium matrix have been studied and a chemical
mechanism is proposed. These studies have been utilized for the determination of uranium in plutonium by Electrothermal Atomization-
Atomic Absorption Spectrometry (ETA-AAS) within the constraints of its stable carbide forming tendency and complexity caused
by formation of plutonium suboxide at high temperatures. In spite of these limitations the analytical range obtained for determination
of uranium is 2.5–100 ng with a sample aliquot of 5 μL containing 5 mg/mL plutonium concentration. The precision of the method
is evaluated as 9% RSD.
Received: 9 September 1997 / Revised: 29 December 1997 / Accepted: 31 December 1997 相似文献
152.
D. R. Wiseman A. N. Andreyev R. D. Page M. B. Smith I. G. Darby S. Eeckhaudt T. Grahn P. T. Greenlees P. Jones R. Julin S. Juutinen H. Kettunen M. Leino A. -P. Leppänen M. Nyman J. Pakarinen P. Rahkila M. Sandzelius J. Sarén C. Scholey J. Uusitalo 《The European Physical Journal A - Hadrons and Nuclei》2007,34(3):275-281
γ -ray transitions in the neutron-deficient nuclei 190, 197Po have been identified using the JUROGAM Ge detector array coupled to the RITU gas-filled separator and the GREAT spectrometer.
The yrast band of 190Po has been firmly established through γ -γ coincidences and extended up to a spin and parity of 14+. It displays similar behaviour to its isotones 186Hg and 188Pb above the 4+ level, thus confirming its prolate nature. In 197Po the band built upon the 13/2+ isomer has been extended up to a spin and parity of 33/2+, while the non-yrast band has been observed for the first time. The behaviour of 197Po is found to be similar to that of the nearby even-mass isotopes, which is consistent with the model in which the i
13/2 neutron is weakly coupled to the states in the even-even core. 相似文献
153.
Si-Jie Yu Sreenivas R. Sukumar Andreas F. Koschan David L. Page Mongi A. Abidi 《Optics and Lasers in Engineering》2007,45(7):808-818
In this paper, we present our experience in building a mobile imaging system that incorporates multi-modality sensors for road surface mapping and inspection applications. Our proposed system leverages 3D laser-range sensors, video cameras, global positioning systems (GPS) and inertial measurement units (IMU) towards the generation of photo-realistic, geometrically accurate, geo-referenced 3D models of road surfaces. Based on our summary of the state-of-the-art systems for a road distress survey, we identify several challenges in the real-time deployment, integration and visualization of the multi-sensor data. Then, we present our data acquisition and processing algorithms as a novel two-stage automation procedure that can meet the accuracy requirements with real-time performance. We provide algorithms for 3D surface reconstruction to process the raw data and deliver detail preserving 3D models that possess accurate depth information for characterization and visualization of cracks as a significant improvement over contemporary commercial video-based vision systems. 相似文献
154.
The structure of 2,5-dihydropyrrole (C4NH7) has been determined by gas-phase electron diffraction (GED), augmented by the results from ab initio calculations employing third-order M?ller-Plesset (MP3) level of theory and the 6-311+G(d,p) basis set. Several theoretical calculations were performed. From theoretical calculations using MP3/6-311+G(d,p) evidence was obtained for the presence of an axial (63%) (N-H bond axial to the CNC plane) and an equatorial conformer (37%) (N-H bond equatorial to the CNC plane). The five-membered ring was found to be puckered with the CNC plane inclined at 21.8 (38) degrees to the plane of the four carbon atoms. 相似文献
155.
A. N. Andreyev D. Ackermann S. Antalic H. J. Boardman P. Cagarda J. Gerl F. P. Heßberger S. Hofmann M. Huyse D. Karlgren A. Keenan H. Kettunen A. Kleinböhl B. Kindler I. Kojouharov A. Lavrentiev C. D. O’Leary M. Leino B. Lommel M. Matos C. J. Moore G. Münzenberg R. D. Page S. Reshitko S. Saro H. Schaffner C. Schlegel M. J. Taylor K. Van de Vel P. Van Duppen L. Weissman K. Heyde 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):39-54
Detailed fine-structure
-decay studies of 188,190Bi were performed using the complete-fusion reactions of 50,52Cr ions with a 142Nd target at the velocity filter SHIP. The evaporation residues were separated in-flight and subsequently identified on the basis of recoil-
, recoil-
-
/X-ray and excitation function measurements. Improved data on the
-decay of 188,190Bi were obtained and a number of new low-lying excited states in the daughters 184,186Tl were observed. An intruder, presumably 10- state was identified in 184Tl, extending the systematics of such states in the odd-odd Tl nuclei beyond the neutron mid-shell at N = 104. Some technical aspects of experiment at recoil separators are also discussed.Received: 14 March 2003, Revised: 1 May 2003, Published online: 2 September 2003PACS:
23.60.+e
decay - 27.70.+q
- 27.80.+w
C.D. OLeary: Present address: Department of Physics, University of York, York, UK.M.J. Taylor: Present address: Department of Physics and Astronomy, Rutgers Univesity, NJ, USA.L. Weissman: Present address: NSCL, Michigan State University, East Lansing, MI 48824-1321 USA.K. Heyde: Present address: EP-ISOLDE, CERN, CH-1211, Geneva 23, Switzerland. 相似文献
156.
We obtain infinite classes of new Einstein-Sasaki metrics on complete and nonsingular manifolds. They arise, after Euclideanization, from BPS limits of the rotating Kerr-de Sitter black hole metrics. The new Einstein-Sasaki spaces L(p,q,r) in five dimensions have cohomogeneity 2 and U(1) x U(1) x U(1) isometry group. They are topologically S(2) x S(3). Their AdS/CFT duals describe quiver theories on the four-dimensional boundary of AdS(5). We also obtain new Einstein-Sasaki spaces of cohomogeneity n in all odd dimensions D = 2n + 1 > or = 5, with U(1)(n + 1) isometry. 相似文献
157.
158.
A body-centered triclinic cell based on the mesh in the shear plane and the period along the pseudo rutile chains is proposed for comparisons of the members of the title series. This cell permits a simple and systematic formulation of the S. Andersson and L. Jahnberg (1961, Ark. Kemi21, 413) model both for the cell parameters with c = (2n ? 1) crutile as the only variable cell parameter and for the atomic positions. The parameters b, β, and γ are found experimentally to obey the model closely, while a and α show a deviation from the model which is proportional to the oxygen deficiency with respect to rutile. The experimental c parameter is shorter by 0.26 ± 3 Å than its value from the model. This shortening is due to the approximate mutual compensation of three structural deviations from the model: the repulsion of the face-sharing Ti atoms, the shortening of the TiTi distances in the chain, and the inclination of the chains toward the interior of the cell. 相似文献
159.
160.
The absorption spectra of Y3Ga5O12:(Fe3+), Y3Ga5O12:(Bi3+) and Y3Ga5O12:(Bi3+, Fe3+) are presented to 40,000 cm-1. Assignments are discussed and the transitions analysed in terms of their involvement in the large Faraday rotation observed in bismuth substituted iron garnets. 相似文献