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Using the reaction138Ba(α,2n)140Ce the magnetic moment of the 10 1 + isomer atE x =3714.7 keV in theN=82 nucleus140Ce has been determined by means of the TDPAD method toμ=+10.3(4)μ N . Measuredg-factors in140Ce are compared to calculations within the shell model with configuration mixing. For the 10 1 + isomer in140Ce the four proton configuration π(1g 7 2/2 ,2d 5 2/2 ) has been found to be dominant. From theg-factor measurement strong contributions of multiparticle excitations to thegp2d 3/2,π3s 1 2 or π1h 11 2 shells and admixtures of neutron excitations to the wave function of the 10 1 + state could be excluded. The strongE1γ-branch of the deexcitation of the 10 1 + isomer in140Ce can be explained by means of small admixtures of configurations which contain the outer subshell excitationsπ2f 7/2 andπ1h 9/2. On this basisE1 transitions experimentally observed in theN=82 nuclei140Ce,141Pr and145Eu may be understood.  相似文献   
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An (α, 2nγ) in-beam study of excited states in 142Nd revealed 27 new levels on top of the 6+ isomer. Nanosecond lifetimes were found for two levels. The measured excitation energies were compared with spherical shell-model predictions obtained from suitably truncated model spaces.  相似文献   
5.
The magnetic moments of the 5/2 1 + state in117Te at 274.4 keV and of the 7/2 1 + state in121Te at 443.1 keV have been determined asμ exp(5/2+)=?0.75(5)n.m. andμ exp(7/2+)=+0.63(7) n.m., respectively, using the TDPAD method and the reactions115,119Sn(α,2n)117,121Te. An evaluation method is described which provides, in case of the normalized time differential patternR(t) exhibits less than half of an oscillation period, a unique value of the Larmor frequency. The comparison of the measured magnetic moments with Nilsson-, soft rotor Coriolis- as well as core-particle coupling calculations gives valuable hints on the shape dependence of magnetic moments and, consequently, on the deformation of different states in the odd transitional nuclei117–125Te. In the light of the core-particle coupling model the positive parity states of117Te and121Te are interpreted as the members ofΔJ=1 andΔJ=2 bands built on thes 1/2,d 3/2,d 5/2 and g7/2 single-particle states, respectively.  相似文献   
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We report the first observation of the attachment of two single plasma filaments created collinearly in the atmosphere by IR femtosecond laser pulses. The linked filamentary structure is electrically conductive and emits sub-THz radiation over its entire length. Concatenation is achieved only for a specific time ordering between the two initial laser pulses. The pulse producing the filament closer to the laser source must be retarded with respect to the other pulse. This special time ordering is attributed to the acceleration of light in a self-guided pulse. Received: 4 March 2003 / Published online: 14 May 2003 RID="*" ID="*"Corresponding author. Fax: +33-1/6931-9996, E-mail: stzortz@ensta.fr  相似文献   
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The design of inhibitors of protein–protein interactions mediating amyloid self‐assembly is a major challenge mainly due to the dynamic nature of the involved structures and interfaces. Interactions of amyloidogenic polypeptides with other proteins are important modulators of self‐assembly. Here we present a hot‐segment‐linking approach to design a series of mimics of the IAPP cross‐amyloid interaction surface with Aβ (ISMs) as nanomolar inhibitors of amyloidogenesis and cytotoxicity of Aβ, IAPP, or both polypeptides. The nature of the linker determines ISM structure and inhibitory function including both potency and target selectivity. Importantly, ISMs effectively suppress both self‐ and cross‐seeded IAPP self‐assembly. Our results provide a novel class of highly potent peptide leads for targeting protein aggregation in Alzheimer’s disease, type 2 diabetes, or both diseases and a chemical approach to inhibit amyloid self‐assembly and pathogenic interactions of other proteins as well.  相似文献   
8.
The g-factor of the first 10+ isomer in140Ce was determined by the time differential perturbed angular distribution method. The result is g(10+) = +1.03(4). The paramagnetism of Ce ions in BaO was studied in the temperature region 300 – 850 K.  相似文献   
9.
By means of the generalized centroid-shift method, the following half-lives were determined:T 1/2(3045 keV)=3.7±0.3 ns in113Sb using the reaction104Pd(12C,p2n) as well asT 1/2 (1322.8 keV)=3.5±0.3 ns,T 1/2(2779.8 keV) =0.50±0.15ns,T 1/2(2874.9 keV)<0.2 ns andT 1/2(3072.9 keV)<0.1 ns in117Sb using the116In(α, 2n) reaction. Three-quasiparticle configurations of the type πd 5/2ν(h11/2 d 3/2) in113,117Sb are found to dominate in the wave functions of the 19/2? states at 3045 and 2780 keV in113Sb and117Sb, respectively. TheB(E2, 19/2? → 15/2?) values in113–119Sb are discussed.  相似文献   
10.
The concept of cardinality of a fuzzy set has received attention from several researchers and has been defined in several apparently independent manners. A systematic investigation of this notion is performed which unifies and improves previous attempts. The cardinality of a fuzzy set, viewed as a fuzzy integer, is related to scalar cardinality indices. The closely related question of the probability of a fuzzy event is dealt with. Lastly, the usefulness of fuzzy cardinality for meaning representation of statements or queries involving fuzzy linguistic quantifiers is emphasized.  相似文献   
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