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971.
We summarize the effects of some unknown supersymmetry breaking mechanism by the addition to the super-QCD lagrangian of explicit, and different, mass terms for the scalar superpartners of quarks and antiquarks. Allowing also a possible Majorana mass for the gluino, we then calculate cross sections for e+e? → two gluinos, a process which may be observable if the gluino is sufficiently long-lived. 相似文献
972.
Per A. Amundsen 《Physics letters. A》1982,89(8):417-419
It is shown that the observed absence of a density effect in inner shell ionization in solids is due to the fact that the required momentum transfer has a wavelength of the order of, or smaller than, the lattice constant, and thus cannot be transmitted to the lattice. This leads to a cut-off in the dielectric function corresponding to electronic binding energies above 1—1.5 keV, depending on the lattice constant. For more strongly bound electrons there shoul be no density effect. 相似文献
973.
Nuclear Overhauser enhancement difference techniques allow the use of CH3-groups as n.O.e. probes exemplified by Z/E conformer assignments. 相似文献
974.
Per Holmqvist 《Journal of Electroanalytical Chemistry》1977,78(2):341-345
Differential capacities of the dropping mercury electrode in contact with KF+KOH solutions were measured by a differential chronopotentiometric method. Adsorption of anions at positive polarisation was confirmed. 相似文献
975.
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978.
The absolute nodal coordinate formulation (ANCF) is characterized by being developed specifically for dynamic analysis of large deformation problems. The objective of the study is to investigate how the shape of the initial mesh configuration influences the obtained numerical solution. After a thorough review of three available formulations, they are used in three different convergence studies. Initially a reference study is conducted to determine how the ANCF performs in an uniform and rectangular mesh. Subsequently, the ANCF methods sensitivity to irregular mesh is investigated and finally, the ability of the ANCF method to describe curved structures is evaluated. This study concludes that thin ANCF shell elements are sensitive to both the initial shape and their loading condition. Furthermore, both the initial configuration and the loading condition affect how the ANCF-based models converge. It is suggested that models containing thin ANCF shell elements are subjected to extensive validation studies, before they are used in a design process. 相似文献
979.
Cyrille Boyer Per B. Zetterlund Michael R. Whittaker 《Journal of polymer science. Part A, Polymer chemistry》2014,52(15):2083-2098
Copper(0) mediated radical polymerization is an efficient and versatile polymerization technique which allows the control of acrylates and methacrylates with an unprecedented maintenance of end group fidelity (~100%) during the polymerization. In this highlight, we summarize recent works using Cu(0)‐mediated radical polymerization for the synthesis of multiblock copolymers via an iterative approach. This approach has been successfully implemented for the synthesis of decablock copolymers, constituted of blocks with a degree of polymerization ranging from 3–4 to 100 units as well as for the preparation of multiblock star polymers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2083–2098 相似文献
980.
Packet video error concealment with Gaussian mixture models. 总被引:1,自引:0,他引:1
Daniel Persson Thomas Eriksson Per Hedelin 《IEEE transactions on image processing》2008,17(2):145-154
In this paper, Gaussian mixture modeling is applied to error concealment for block-based packet video. A Gaussian mixture model for video data is obtained offline and is thereafter utilized online in order to restore lost blocks from spatial and temporal surrounding information. We propose estimators on closed form for missing data in the case of varying available neighboring contexts. Our error concealment strategy increases peak signal-to-noise ratio compared to previously proposed schemes. Examples of improved subjective visual quality by means of the proposed method are also supplied. 相似文献