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61.
Two-dimensional γ-ray energy correlations have been measured at high spins in1800s with the TESSA2 spectrometer. The Eγ ? Eγcorrelation matrix displays ridges characteristic of rotational bands with different energy separations of 96± and 72± keV for the energy regions of 660 to 840 keV and 975 to 1170 keV, respectively. The separation of these ridges remains constant in both energy regions. The dynamical moments of inertia are θ(2) =83±3 and 111±5 ?2/MeV, respectively. The latter value suggests superdeformation in1800s with an axis ratio c/a=1.76 (β2 ?0.64) at high spins.  相似文献   
62.
High-spin states in the oblate-deformed nuclei195Hg and196Hg were populated in the198Pt(α, xn) reaction and investigated by in-beamγ-ray spectroscopy using six Compton-suppressed Ge detectors. The level schemes of both nuclei are extended considerably. The level structure is interpreted within the framework of the cranked shell model. Good agreement is obtained between model predictions and experimental results.  相似文献   
63.
A new magnetic coupling is outlined in which the balance and the pan or crucible could be separated.  相似文献   
64.
While the hydrophobic effect is, for many systems, one of the most relevant interactions, it may be said that in the case of biological systems this effect becomes of determinant importance. Although the matter has been analyzed extensively, certain aspects are yet to be elucidated. Hence, the study on the behavior of the hydrophobic effect with temperature, and particularly with pressure deserves further investigation; model systems may help us in the task. We have analyzed the behavior of Lennard-Jones particles in water by means of molecular dynamics simulation under different conditions of size, concentration, temperature, and pressure. Following the formation of particle aggregates we can observe an increase of the hydrophobic effect with temperature and a strong weakening of the effect at high pressures. The results agree with the experimental evidence and show the ability of molecular dynamics simulation to account for the behavior of nonpolar substances under different conditions, provided that the intermolecular interactions used are adequate.  相似文献   
65.
During the photocycle of quinone-blocked photosynthetic reaction centers (RCs), photochemically induced dynamic nuclear polarization (photo-CIDNP) is produced by polarization transfer from the initially totally electron polarized electron pair and can be observed by 13C magic-angle spinning (MAS) NMR as a strong modification of signal intensities. The same processes creating net nuclear polarization open up light-dependent channels for polarization loss. This leads to coherent and incoherent enhanced signal recovery, in addition to the recovery due to light-independent longitudinal relaxation. Coherent mixing between electron and nuclear spin states due to pseudosecular hyperfine coupling within the radical pair state provides such a coherent loss channel for nuclear polarization. Another polarization transfer mechanism called differential relaxation, which is based on the long lifetime of the triplet state of the donor, provides an efficient incoherent relaxation path. In RCs of the purple bacterium Rhodobacter sphaeroides R26, the photochemical active channels allow for accelerated signal scanning by a factor of 5. Hence, photo-CIDNP MAS NMR provides the possibility to drive the NMR technique beyond the T1 limit.  相似文献   
66.
We report a general concept based on a selective electrochemical ion pump used for creating concentration perturbations in thin layer samples (~40 μL). As a first example, hydrogen ions are released from a selective polymeric membrane (proton pump) and the resulting pH is assessed potentiometrically with a second membrane placed directly opposite. By applying a constant potential modulation for 30 s, an induced proton concentration of up to 350 mM may be realized. This concept may become an attractive tool for in situ titrations without the need for sampling, because the thin layer eventually re‐equilibrates with the contacting bulk sample. Acid–base titrations of NaOH and Na2CO3 are demonstrated. The determination of total alkalinity in a river water sample is carried out, giving levels (23.1 mM ) comparable to that obtained by standard methods (23.6 mM ). The concept may be easily extended to other ions (cations, anions, polyions) and may become attractive for environmental and clinical applications.  相似文献   
67.
68.
A non-yrast superdeformed band has been found in146Gd using the110Pd(40Ar, 4n)146Gd reaction. The nuclear assignment was made from the analysis of an experiment using a backed target. This band and the previously identified yrast SD band are probably not signature partners.  相似文献   
69.
The European Physical Journal C - We construct the five loop anomalous dimensions of the basic fields in Quantum Chromodynamics in a linear covariant gauge in the modified Regularization Invariant...  相似文献   
70.
Dynamic multilevel systems can be assembled from molecular building blocks through two or more reversible reactions that form covalent bonds. Molecular networks of dynamic multilevel systems can exhibit different connectivities between nodes. The design and creation of molecular networks in multilevel systems require control of the crossed reactivity of the functional groups (how to connect nodes) and the conditions of the reactions (when to connect nodes). In recent years, the combination of orthogonal and communicating reactions, which can be simultaneous or individually activated, has produced a variety of systems that have given rise to macrocycles and cages, as well as molecular motors and multicomponent architectures on surfaces. A given set of reactions can lead to systems with unique responsiveness, compositions, and functions as a result of the relative reactivities. In this Concept article, different molecular networks from synthetic systems that can be produced by combinations of different reaction types are discussed. Moreover, applications of this chemistry are highlighted, and future perspectives are envisioned.  相似文献   
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