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Szabolcs Osváth Nóra Vajda Zsuzsa Molnár Éva Kovács-Széles Mihály Braun Máté Halász 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(1):31-38
A radioanalytical method (based on separation using UTEVA columns and ICP-MS measurement) has been used for determination of 93Zr in 37 nuclear power plant samples. As 93Nb might affect the detection of 93Zr, Monte Carlo activation model was used to calculate the expected 93Zr/natZr mass ratio, which was compared to measured ones. It was found, that a decontamination factor of 103 is sufficient to get a measurement uncertainty of less than 10%. 相似文献
146.
This paper presents an experimental and numerical investigation on the natural convection flow in a cylindrical model hydrothermal
reactor. The flow is visualized non-intrusively and simulated with a conjugate computational model. Results show that the
flow structure consists of wall layers and core flows. In the lower half, the flows are steady due to the porous media. The
three-dimensional unsteady upper core flow is driven by the streams originated from the wall layer collision. The thermal
condition in the upper half core region is mainly determined by the total heat flow rate specified on the lower sidewall;
while the variations of porous media parameters, in the normal range for hydrothermal crystal growth process, have minor effects. 相似文献
147.
A poorly understood step in the transition from a chemical to a biological world is the emergence of self-replicating molecular systems. We study how a precursor for such a replicator might arise in a hydrothermal RNA reactor, which accumulates longer sequences from unbiased monomer influx and random ligation. In the reactor, intra- and intermolecular base pairing locally protects from random cleavage. By analyzing stochastic simulations, we find temporal sequence correlations that constitute a signature of information transmission, weaker but of the same form as in a true replicator. 相似文献
148.
M. A. Braun L. N. Lipatov M. Yu. Salykin M. I. Vyazovsky 《The European Physical Journal C - Particles and Fields》2011,71(5):1639
Application of the effective action formalism is studied for processes in which the reggeons may split. It is shown that the
gluon production on two centers is described by the contribution of the Reggeon-to-two-Reggeons-plus-Particle vertex supplemented
by certain singular contributions from the double gluon exchange. The rules for longitudinal integrations are established
from the comparison to perturbative QCD amplitude. Convenient expressions for application to the inclusive gluon production
are derived. 相似文献
149.
Johannes Braun Johannes Buchmann Ciaran Mullan Alex Wiesmaier 《Designs, Codes and Cryptography》2014,71(3):459-478
Sensitive electronic data may be required to remain confidential for long periods of time. Yet encryption under a computationally secure cryptosystem cannot provide a guarantee of long term confidentiality, due to potential advances in computing power or cryptanalysis. Long term confidentiality is ensured by information theoretically secure ciphers, but at the expense of impractical key agreement and key management. We overview known methods to alleviate these problems, whilst retaining some form of information theoretic security relevant for long term confidentiality. 相似文献
150.
Theoretical and Mathematical Physics - In perturbative QCD, we study a set of pomeron fan diagrams propagating from a projectile to A nucleons in the nucleus target for finite A and investigate its... 相似文献