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991.
C. Scheidenberger K. Beckert P. Beller F. Bosch C. Brandau D. Boutin L. Chen B. Franzke H. Geissel R. Knöbel C. Kozhuharov J. Kurcewicz S. A. Litvinov Yu. A. Litvinov M. Mazzocco G. Münzenberg F. Nolden W. R. Plaß M. Steck B. Sun H. Weick M. Winkler 《Hyperfine Interactions》2006,173(1-3):61-66
One important goal of the ILIMA project at FAIR is the study of masses and decay properties of relativistic isomeric beams
stored and cooled in the planned storage-ring complex. A new scheme is described, where a storage-cooler ring is used for
high-resolution mass separation. Experimental results on the separation of the isobaric pair 140Pr-140Ce are presented.
P. Beller, deceased. 相似文献
992.
Least-squares finite difference (LSFD) method, one of mesh-free methods, is used to solve slider air bearings problem through discritizing the generalized Reynolds equation into nonlinear systems of algebraic equations. Two approximation schemes for the linearization of these equations are presented and compared. And, some new techniques to search supporting points for the reference node in the mesh-free method were proposed and explored. Therefore, these improvements eliminate some potential limitation of the LSFD method previously published and further facilitate its employment in complex slider models. Advanced step slider as an example of negative pressure sliders is simulated and verified using the improved LSFD mesh-free method in head disk systems. 相似文献
993.
The subject of spectral distribution methods where one derives and applies the locally smoothed forms of observables in nuclei
is briefly reviewed. It is well understood that the local forms (with respect to energy) of the level density function, expectation
values and strength densities are Gaussian, linear (or ratio of Gaussians) and a bivariate Gaussian respectively. To accomodate
symmetries in the above forms, one has to deal with multivariate distributions in general; for example the angular-momentum
(J) decomposition leads to a bivariate Gaussian form for the level density. These results extend to indefinitely large spaces
by method of partitioning and they generate convolution forms. The origin of these remarkable spectral properties is discussed
and shell model examples are given to substantiate their applicability to nuclear systems. Spectral distribution theory is
a practical, usable theory because the smoothed forms are defined in terms of traces of low particle-rank operators, and the
trace information propagates. Finally we discuss the application of the spectral methods for a wide range of nuclear problems;
these include binding energies, orbit occupancies, electromagnetic andβ-decay sum rule quantities, analysis of operators, symmetry breaking, numerical level densities, and determination of bounds
on time-reversal non-invariant part of nucleon-nucleon interaction. 相似文献
994.
Y. Xu K. S. Krane M. A. Gummin J. L. Wood M. M. Jarrio J. B. Breitenbach E. F. Zganjar D. Rupnik H. K. Carter P. F. Mantica Jr. B. E. Zimmerman 《Hyperfine Interactions》1992,75(1-4):481-487
The184Au→184Pt decay, studied on-line with the UNISOR facility at HHIRF, is discussed. Gamma-ray and conversion-electron spectroscopy
of184Pt as well as on-line nuclear orientation measurements of184Au were done. A new low-lying level scheme of184Pt is proposed. Two coexisting bands with different deformations and their respective γ-vibrational bands are established.
Internal conversion coefficients for interband transitions between states with the same spin are extracted from the spectroscopy
measurements. The relative E0 contents of the transitions are determined by combining internal conversion coefficients with
E2/M1 mixing ratios deduced from gamma-ray anisotropies measured from oriented nuclei. 相似文献
995.
J. W. Lee Y. Takase B. A. Newman J. I. Scheinbeim 《Journal of Polymer Science.Polymer Physics》1991,29(3):273-277
Cold-drawn Nylon-11 films, which were prepared by stretching the melt-quenched films to a draw ratio of 2.8: 1 at room temperature, were found to exhibit an electric displacement versus electric field hysteresis loop. The results confirmed that the Nylon-11 film exhibited ferroelectric behavior at or below room temperature. The coercive fields were 65, 98, 125, 160, and 215 MV/m at 20, 0, ?20, ?40, and ?60°C and the remanent polarization at ?20°C (where there was considerably less dc conduction) was 56 mC/m2. Switching of the polarization was almost completed within 20 ms. 相似文献
996.
X-ray diffraction studies have been undertaken on aqueous solutions of hydroxy propylcellulose (HPC) over a wide range of the scattering vector Q. The experiments revealed only modest differences in local structure on a distance scale ca. 5–300 Å despite the fact that they covered concentrations generally interpreted as ranging from the isotropic (35.1 wt %) to the anisotropic liquid crystalline (LC) phase (53.5 wt %). Several models were used to interpret the small-angle scattering data, and each gave similar structural parameters and extrapolated intensities ( Q → 0) for both solutions. Peaks were observed with d-spacings ca. 12–17 Å in both materials. Wide-angle x-ray scattering (WAXS) showed slightly increased local order over a size range ca. 5–20 Å for the anisotropic solution, and this is consistent with a greater intensity of the 13 Å peak in this material. It is difficult to reconcile these findings with an interpretation of the LC state involving major differences with the isotropic phase and a high degree of orientational order extending over long length scales. 相似文献
997.
V. N. Korneev P. M. Sergienko V. A. Shlektarev V. M. Aul’chenko M. A. Bukin V. M. Titov B. P. Tolochko M. R. Sharafutdinov A. V. Zabelin E. I. Litvinov A. M. Matyushin V. G. Stankevich M. A. Sheromov O. V. Naida A. A. Vazina 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2007,1(1):99-104
To modernize the DICSI station, new hardware and software have been created according to the conditions of the operating storage ring “Sibir’-2” beam channel. The recording system has been successfully tested on the operating channel of the storage ring VEPP-3 (Budker Institute of Nuclear Physics Siberian Branch, Russian Academy of Sciences, Novosibirsk) using the time-resolved “diffraction cinema” technique in studying real biological objects in the static and dynamic modes of data accumulation. At the DICSI station, structural changes in medical and biological objects are permanently investigated. The specific structure dimensions of these objects are in the nanometric range. 相似文献
998.
A rapid single-step method for the electrosynthesis of chloro and bromo complexes of palladium(II and IV), viz. M2[PdX4] and M2[PdX6], by the dissolution of a palladium anode in chloride or bromide containing media is described. Electrolysis of dilute HX solution in the presence of pyridine, 2,2′-bipyridyl or 1,10-phenanthroline gives rise to non-electrolytes, e.g. trans-[PdX2(py)2], [PdX2(bipy)] and [PdX2(phen)]. Anodic oxidation of palladium in HX medium in the presence of acetonitrile and benzonitrile also gives the non-electrolytes trans-[PdX2(CH3CH2NH2)2] and trans-[PdX2(C6H5CH2NH2)2], respectively. 相似文献
999.
1000.
B. Abramovitz 《Acta Appl Math》1994,36(3):211-226
In this work, we consider the regularization method for linear ill-posed problems. For operators and approximating subspaces satisfying certain conditions and for a specific form of the regularization parameter, upper and lower bounds are given for the condition number of the corresponding discrete problem. 相似文献