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1.
High-spin states in 181Ta have been studied via the 176Yb(11B,α2n) reaction at 52 MeV using the PEX array and at 57 MeV using the NORDBALL array, with α-particle detection. The previously known, Kπ=(7/2)+ ground state band and Kπ=(9/2) band have been extended to spins (29/2)+ and (31/2), respectively. Two new one-quasiparticle bands, the Kπ=(5/2)+ band built on the known (5/2)+ isomer and a Kπ=((1/2)) band have been observed. Two other rotational bands with three-quasiparticle structure, Kπ=(15/2) and ((19/2)+ with π(7/2)[404]ν2(1/2)[510](9/2)[624] and π(9/2)[514]ν2(1/2)[510](9/2)[624] configurations, respectively, have been newly observed. The half-life of the Kπ=((19/2)+) bandhead which decays to the head of the (15/2) band has been measured to be 140(36) ns. However, transitions from the ((19/2)+) state to the (15/2) band have not been observed. Received: 26 August 1998  相似文献   
2.
Phytochemical investigations on the EtOH extract of Clematis viticella led to the isolation of six flavonoid glycosides, isoorientin (1), isoorientin 3′-O-methyl ether (2), quercetin 7-O-α-L-rhamnopyranoside (3), quercetin 3,7-di-O-α-L-rhamnopyranoside (4), manghaslin (5) and chrysoeriol 7-O-β-D-glucopyranoside (6), one phenylethanol derivative, hydroxytyrosol (7), along with three phenolic acids, caffeic acid (8), (E)-p-coumaric acid (9) and p-hydroxybenzoic acid (10). The structures of the isolates were elucidated on the basis of NMR and HR-MS data. All compounds were isolated from C. viticella for the first time. Compounds 7 and 8 showed significant anti-inflammatory activity at 100 μM by reducing the release of NO in LPS-stimulated macrophages comparable to positive control indomethacin. Compounds 3 and 7 exhibited anti-inflammatory activity through lowering the levels of TNF-α while 1, 3 and 5 decreased the levels of neopterin better than the positive controls.  相似文献   
3.
Conclusions Premodulation of the electron beam by an external signal and appropriate choice of parameters for a synchronized CRM monotron increase the starting values of the parameters Is proportional to the beam current and the Q's of competing modes. In maximum-efficiency regimes (for optimal beam current and externalsignal frequency), the stability of single-mode oscillations in a CRM monotron is ensured for any competing-mode Q's, regardless of the values of the parameters,, , X, or n.Scientific-Research Institute of Radio Physics. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 19, No. 3, pp. 453–459, March, 1976.  相似文献   
4.
The (mixed finite element) discretization of the linearized Navier–Stokes equations leads to a linear system of equations of saddle point type. The iterative solution of this linear system requires the construction of suitable preconditioners, especially in the case of high Reynolds numbers. In the past, a stabilizing approach has been suggested which does not change the exact solution but influences the accuracy of the discrete solution as well as the effectiveness of iterative solvers. This stabilization technique can be performed on the continuous side before the discretization, where it is known as ‘grad‐div’ (GD) stabilization, as well as on the discrete side where it is known as an ‘augmented Lagrangian’ (AL) technique (and does not change the discrete solution). In this paper, we study the applicability of ??‐LU factorizations to solve the arising subproblems in the different variants of stabilized saddle point systems. We consider both the saddle point systems that arise from the stabilization in the continuous as well as on the discrete setting. Recently, a modified AL preconditioner has been proposed for the system resulting from the discrete stabilization. We provide a straightforward generalization of this approach to the GD stabilization. We conclude the paper with numerical tests for a variety of problems to illustrate the behavior of the considered preconditioners as well as the suitability of ??‐LU factorization in the preconditioners. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
5.
Nanoparticle labels have enhanced the performance of diagnostic, screening, and other measurement applications and hold further promise for more sensitive, precise, and cost-effective assay technologies. Nevertheless, a clear view of the biomolecular interactions on the molecular level is missing. Controlling the ratio of molecular recognition over undesired nonspecific adhesion is the key to improve biosensing with nanoparticles. To improve this ratio with an aim to disallow nonspecific binding, a more detailed perspective into the kinetic differences between the cases is needed. We present the application of two novel methods to determine complex binding kinetics of bioconjugate nanoparticles, interferometry, and force spectroscopy. Force spectroscopy is an atomic force microscopy technique and optical interferometry is a direct method to monitor reaction kinetics in second-hour timescale, both having steadily increasing importance in nanomedicine. The combination is perfectly suited for this purpose, due to the high sensitivity to detect binding events and the ability to investigate biological samples under physiological conditions. We have attached a single biofunctionalized nanoparticle to the outer tip apex and studied the binding behavior of the nanoparticle in a sandwich-type immunoassay using dynamic force spectroscopy in millisecond timescale. Utilization of the two novel methods allowed characterization of binding kinetics in a time range spanning from 50 ms to 4 h. These experiments allowed detection and demonstration of differences between specific and nonspecific binding. Most importantly, nonspecific binding of a nanoparticle was reduced at contact times below 100 ms with the solid-phase surface.
Figure A single biofunctionalized nanoparticle was attached to the outer tip apex and the binding behavior of the nanoparticle in a sandwich-type immunoassay, A) without analyte, B) with analyte and C) saturating analyte concentration, was recorded using dynamic force spectroscopy in millisecond timescale. The setting allowed measurement of the association speed of nonspecific binding.
  相似文献   
6.
We present phase diagrams for a polarized Fermi gas in an optical lattice as a function of temperature, polarization, and lattice filling factor. We consider the Fulde-Ferrel-Larkin-Ovchinnikov (FFLO), Sarma or breached pair, and BCS phases, and the normal state and phase separation. We show that the FFLO phase appears in a considerable portion of the phase diagram. The diagrams have two critical points of different nature. We show how various phases leave clear signatures to momentum distributions of the atoms which can be observed after time of flight expansion.  相似文献   
7.
We study a quasi-two-dimensional superfluid Fermi gas where the confinement in the third direction is due to a strong harmonic trapping. We investigate the behavior of such a system when the chemical potential is varied and find strong modifications of the superfluid properties due to the discrete harmonic oscillator states. We show that such quasi-two-dimensional behavior can be created and observed with current experimental capabilities.  相似文献   
8.
Excited states of 99Ag were populated via the 50Cr + 58Ni (261 MeV) reaction using the NORDBALL detector array equipped with charged-particle and neutron detector systems for reaction channel separation. On the basis of the measured γγ-coincidence relations and angular distribution ratios a significantly extended level scheme has been constructed up to E x ∼ 7.8 MeV and I = 35/2. The experimental results were described within the framework of the shell model. Candidates for states fully aligned in the πg 9/2 -3ν(d 5/2, g 7/2)2 valence configuration space were found at 4109 and 6265 keV. Received: 18 June 2002 / Accepted: 11 October 2002 / Published online: 4 February 2003 RID="a" ID="a"e-mail: sohler@atomki.hu Communicated by J. ?yst?  相似文献   
9.
10.
New excited states have been observed in the neutron deficient isotope 98Ag following the 58Ni+50Cr →108Te* heavy–ion reaction. One of these states may be interpreted as a maximum spin aligned state of the πg9/2 −3νg7/2 configuration. Other possible interpretations within the nuclear shell model are discussed as well. Received: 24 October 1997  相似文献   
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