Search results for " Deformation"
showing 10 items of 167 documents
Pairs of nontrivial smooth solutions for nonlinear Neumann problems
2020
Abstract We consider a nonlinear Neumann problem driven by a nonhomogeneous differential operator with a reaction term that exhibits strong resonance at infinity. Using variational tools based on the critical point theory, we prove the existence of two nontrivial smooth solutions.
Change in structure between the $I = 1/2$ states in $^{181}$Tl and $^{177,179}$Au
2018
Abstract The first accurate measurements of the α-decay branching ratio and half-life of the I π = 1 / 2 + ground state in 181Tl have been made, along with the first determination of the magnetic moments and I = 1 / 2 spin assignments of the ground states in 177,179Au. The results are discussed within the complementary systematics of the reduced α-decay widths and nuclear g factors of low-lying, I π = 1 / 2 + states in the neutron-deficient lead region. The findings shed light on the unexpected hindrance of the 1 / 2 + → 1 / 2 + , 181Tl → g 177 Aug α decay, which is explained by a mixing of π 3 s 1 / 2 and π 2 d 3 / 2 configurations in 177Aug, whilst 181Tlg remains a near-pure π 3 s 1 / 2 .…
β decay studies of n-rich Cs isotopes with the ISOLDE Decay Station
2017
R. Lica et al. -- 14 pags., 7 figs., tab. -- Open Access funded by Creative Commons Atribution Licence 3.0
Evidence of octupole-phonons at high spin in 207Pb
2019
A lifetime measurement of the 19/2 state in Pb has been performed using the Recoil Distance Doppler-Shift (RDDS) method. The nuclei of interest were produced in multi-nucleon transfer reactions induced by a Pb beam impinging on a Mo enriched target. The beam-like nuclei were detected and identified in terms of their atomic mass number in the VAMOS++ spectrometer while the prompt γ rays were detected by the AGATA tracking array. The measured large reduced transition probability B(E3,19/2→13/2)=40(8) W.u. is the first indication of the octupole phonon at high spin in Pb. An analysis in terms of a particle-octupole-vibration coupling model indicates that the measured B(E3) value in Pb is compa…
Nuclear charge radii of 62−80Zn and their dependence on cross-shell proton excitations
2019
Nuclear charge radii of 62−80Zn have been determined using collinear laser spectroscopy of bunched ion beams at CERN-ISOLDE. The subtle variations of observed charge radii, both within one isotope and along the full range of neutron numbers, are found to be well described in terms of the proton excitations across the Z=28 shell gap, as predicted by large-scale shell model calculations. It comprehensively explains the changes in isomer-to-ground state mean square charge radii of 69−79Zn, the inversion of the odd-even staggering around N=40 and the odd-even staggering systematics of the Zn charge radii. With two protons above Z=28, the observed charge radii of the Zn isotopic chain show a cum…
Lifetime measurements of excited states in $^{163}$W and the implications for the anomalous B(E2) ratios in transitional nuclei
2019
Grahn, Tuomas/0000-0002-6255-2279; Herzan, Andrej/0000-0002-6736-7638; Cullen, Dave/0000-0002-0041-1606; Barber, Liam/0000-0002-7409-9352; Keatings, James Michael/0000-0003-4271-8021; SAYGI, BAHADIR/0000-0001-5406-506X; Greenlees, Paul/0000-0002-5986-5274; Spagnoletti, Pietro/0000-0002-7674-989X; Parr, Edward/0000-0001-6204-4461; Bondili, S Nara Singh/0000-0002-4096-2429
Comment on "Displacement along the Karakoram fault, NW Himalaya, estimated from LA-ICP-MS U Pb dating of offset geologic markers" published by Shifen…
2013
International audience; Field evidence for syn-deformation migmatization and crystallization along the Karakorum fault contradicts the study of Wang et al. (2012). The ages of such magmatic rocks provide minimum ages for the onset of deformation at similar to 23 Ma in North Ayilari and similar to 19 Ma in Tangtse. The onset of deformation at 12 Ma in the Ayilari range inferred by Wang et al. (2012) from a muscovite Ar/Ar age is a cooling age, thus only a minimum age. The similar to 60 Ma granodiorite bodies, the ophiolitic rocks and the south Kailash thrust that are correlated across the fault to provide a 52 +/- 2 km finite offset do not define reliable piercing points. Such observations a…
Bounds on transient phase plastic deformations in optimal design of steel frames subjected to cyclic loads
2009
A minimum volume multicriterion design of elastic perfectly plastic steel frames subjected to a combination of quasi-static fixed and cyclic loads, bounding the transient phase plastic deformations, is proposed. The problem is formulated according to a plastic shakedown criterion, so that incremental and instantaneous collapse are certainly prevented when the frame is subjected to very strongly amplified cyclic loads. The further condition that the structure must also behave elastically in serviceability conditions is imposed. Since the steady-state loading history is known it is possible to directly bound the steady-state plastic deformations. By applying a suitable own bounding theorem, i…
An Annotated History of Craniofacial Surgery and Intentional Cranial Deformation
2001
The history of craniofacial surgery and the use of intentional cranial deformation is a long and varied one. Researching some of the earliest medical writings and reviews of early terracotta and stone figures from throughout the world clearly revealed that these two forms of treatment were widely extant. Intentional cranial deformation was used for a number of reasons including beautification, tribal identification, and social stature. The development of craniofacial surgery is a more modern practice and its historical evolution is reviewed in the context of techniques and the personalities involved.
Two-dimensional apparent microfabric of the basal Late Weichselian till and associated shear zone: case study from western Latvia
2008
The examination of glacial sediments in thin sections has become a common procedure in recent years. Apparent sand grain orientation (microfabric) in thin sections is one of the key elements marking certain microstructures. In an attempt to make till micromorphology studies less subjective and investigate the orientation of sand-sized particles in tills, we have developed an image analysis procedure to measure and analyse the spatial distribution of the till microfabric. We studied 13 thin sections of the Weichselian subglacial till and basal shear zone outcropping in the Baltic Sea bluffs at the Ziemupe site in western Latvia. The results were visualized as a two-dimensional grid of rose d…