2023 · AI 安全与对齐 · Singlet fission is a photophysical process that provides a pathway for more efficient harvesting of solar energy in photovoltaic devices. The design of singlet fission candidates is non-trivial and requires careful optim…
2022 · 核能 · The dynamics of low-energy-induced fission is explored using a consistent microscopic framework that combines the time-dependent generator coordinate method (TDGCM) and time-dependent nuclear density functional theory (T…
2020 · 核能 · Significant progress in the understanding of the fission process within a microscopic framework has been recently reported. Even though the complete description of this important nuclear reaction remains a computationall…
2016 · 核能 · Background: An electron localization measure was originally introduced to characterize chemical bond structures in molecules. Recently, a nucleon localization based on Hartree-Fock densities has been introduced to invest…
2014 · 核能 · Eighty years after its experimental discovery, a description of induced nuclear fission based solely on the interactions between neutrons and protons and quantum many-body methods still poses formidable challenges. The g…
2014 · 量子材料 · The quasifission mechanism hinders fusion in heavy systems through breakup within zeptoseconds into two fragments with partial mass equilibration. Its dependence on the structure of both the collision partners and the fi…
2012 · 核能 · Until now, the mass asymmetry in the nuclear fission process has been understood in terms of the strong influence of the nuclear structure of the nascent fragments. Recently, a surprising asymmetric fission has been disc…
2011 · 核能 · A collective mass tensor derived from the cranking approximation to the adiabatic time-dependent Hartree-Fock-Bogoliubov (ATDHFB) approach is compared with that obtained in the Gaussian overlap approximation (GOA) to the…
2004 · 核能 · Multi-modal nuclear fission of fermium isotopes at low excitation energy is dynamically investigated. The multidimensional Langevin equation is used for the dynamical calculation. We use the potential energy taking accou…
1989 · 核能 · The Senior Committee on Environmental, Safety, and Economic Aspects of Magnetic Fusion Energy (ESECOM) was organized in late 1985 to provide an up-to-date assessment of magnetic fusion energy's prospects for meeting this…
1988 · 核能 · The process of nuclear fission induced by nonlinear radiative coupling to atomic electrons is considered. For 248-nm radiation at an intensity of \ensuremath{\simeq}${10}^{21}$ W/${\mathrm{cm}}^{2}$, highly relativistic …
1988 · 核能 · The Senior Committee on Environmental, Safety, and Economic Aspects of Magnetic Fusion Energy (ESECOM) summarizes its recent assessment of magnetic fusion energy’s (MFE’s) prospects for providing energy with economic, en…
1983 · 核能 · Induced nuclear fission is viewed as a diffusion process of the fission degree of freedom over the fission barrier. We describe this process in terms of a Fokker-Planck equation which contains the fission variable and it…
1979 · 核能 · We develop a unified nuclear potential for the description of large-scale nuclear collective motion and find that it satisfactorily reproduces experimental data for heavy-ion elastic scattering, fusion, fission, and grou…
1977 · 核能 · We introduce a degree of freedom to describe the rupture of the neck in nuclear fission and calculate the point at which the neck ruptures as the nucleus descends dynamically from its fission saddle point. This is done b…
1976 · 核能 · A static model of nuclear fission is proposed based on the assumption of statistical equilibrium among collective degrees of freedom at the scission point. The relative probabilities of formation of complementary fission…
1973 · 核能 · The two-center shell model for fission has been generalized to include asymmetric deformations. The calculation of the potential energy involves four independent shape variables, where only two were required in the symme…
1972 · 核能 · This paper reviews various results related to the single-particle structure in spherical and deformed nuclei, discussed from the viewpoint of the so-called shell-correction method. This method stresses the importance of …
1962 · 核能 · New information concerning half-lives and fractional independent and fractional cumulative yields of fission products has been obtained from experiments in which adjacent elements in fission-product chains were rapidly s…
2018 · 核能 · An overview is given on some of the main advances in experimental methods, experimental results and theoretical models and ideas of the last years in the field of nuclear fission. New experimental approaches extended the…
2016 · 量子材料 · This article reviews how nuclear fission is described within nuclear density functional theory. A distinction should be made between spontaneous fission, where half-lives are the main observables and quantum tunnelling t…
2009 · 核能 · Structural materials represent the key for containment of nuclear fuel and fission products as well as reliable and thermodynamically efficient production of electrical energy from nuclear reactors. Similarly, high-perfo…
2008 · 核能 · A statistical model calculation for the decay of a compound nucleus is presented where the compound nuclear spin dependence of the Kramers modified fission width is included. Specifically, the spin dependences of the fre…
2002 · 核能 · A theoretical model of one-body nuclear friction, which was developed earlier, namely, the chaos-weighted wall formula, is applied to a dynamical description of compound nuclear decay in the framework of the Langevin equ…
2001 · 核能 · Geomagnetic field reversals and changes in intensity are understandable from an energy standpoint as natural consequences of intermittent and/or variable nuclear fission chain reactions deep within the Earth. Moreover, d…
1994 · 核能 · This article addresses the historical problem of how it was possible for Lise Meitner and her nephew Otto Robert Frisch to arrive at their novel interpretation of nuclear fission at the end of 1938. To understand this re…
1992 · 核能 · The most interesting process of collective flow of nuclear matter is the fission process. The time-scale of this process at moderate to high excitation energies is reviewed. Various methods to measure the time associated…
1984 · 核能 · Using a Fokker-Planck equation, we consider induced nuclear fission for large values of the friction constant. Then, the equation simplifies to the Smoluchowski equation which we solve using a method of van Kampen. We fi…
1980 · 核能 · The concept of the double-humped fission barrier of actinide nuclei has made possible an understanding of a vast amount of data on nuclear fission during the past decade. In this article the analysis of most available re…
1974 · 核能 · The experimental evidence supporting the double-humped character of the fission barrier in actinide nuclei is reviewed and compared to theoretical predictions. The discussion covers the existence and half-life systematic…
1971 · 核能 · Potential-energy surfaces and shell-correction-energy surfaces for nuclei in the $A\ensuremath{\simeq}200$ region and for actinide ($A\ensuremath{\gtrsim}230$) have been calculated in the improved two-center model. These…
1963 · 核能 · The Bardeen, Cooper, Schrieffer formalism is applied to a calculation of the mean-square projection ${{K}_{0}}^{2}$ of the angular momentum along the symmetry axis of an excited deformed nucleus. The results are compared…
1962 · 核能 · A measurement of the probability of emission of long-range particles, which are known to be predominantly alpha particles, made with a multiple ionization chamber gave the following results for spontaneous fission: ${\ma…
1959 · 核能 · It is shown that Weisskopf's nuclear evaporation theory, when allowance is made for the expected distribution of nuclear temperatures of fission fragments, predicts an essentially Maxwellian distribution of fission neutr…
1958 · 核能 · A semiempirical equation for fission thresholds has been extended to include the effects of unpaired nucleons on the rate of spontaneous fission. Excitation functions for the ($\ensuremath{\alpha}, 4n$) reactions of ${\m…
1956 · 核能 · A statistical theory is developed, according to which the relative probability of a mode of fission is determined by the total excitation energy of its two fragments calculated at the moment just before separation. In or…
1953 · 核能 · An attempt is made to correlate in a unified picture the features of the empirical evidence on nuclear constitution, some of which appear to require for their explanation the liquid drop model as others require the indep…
1939 · 核能 · Publisher Summary From considerations of statistical mechanics analogous to those applied to the evaporation-like nuclear disintegrations, it follows that the probability of occurrence of fission becomes comparable to th…
2015 · 核能 · We suggest a small set of fission observables to be used as test cases for validation of theoretical calculations. The purpose is to provide common data to facilitate the comparison of different fission theories and mode…
1994 · 核能 · We study the temperature and angular momentum dependence of the shell effects in the fissioning nucleus by means of a theoretical analysis of the total fission probability. We find clear evidence of the disappearance of …
1975 · 核能 · By introducing charge asymmetry as a new dynamical collective coordinate in the asymmetric two-center shell model, the nuclear charge dispersion in the fission of $^{236}\mathrm{U}$ is calculated without using any free p…
1970 · 核能 · A two-center shell model with oscillator potentials, $\stackrel{\ensuremath{\rightarrow}}{\mathrm{l}}\ifmmode\cdot\else\textperiodcentered\fi{}\stackrel{\ensuremath{\rightarrow}}{\mathrm{s}}$ forces, and ${\stackrel{\ens…
1966 · 核能 · Following a major shortage of 99Mo in the 2009–2010 period, concern grew that the aging reactor production facilities needed to be replaced. Most producers were using highly enriched 235U (HEU) as the target material. Th…
1959 · 核能 · Following a major shortage of 99Mo in the 2009–2010 period, concern grew that the aging reactor production facilities needed to be replaced. Most producers were using highly enriched 235U (HEU) as the target material. Th…
1939 · 核能 · On the basis of the liquid drop model of atomic nuclei, an account is given of the mechanism of nuclear fission. In particular, conclusions are drawn regarding the variation from nucleus to nucleus of the critical energy…
1989 · 核能 · The news of the discovery of nuclear fission, by Otto Hahn and Fritz Strassmann in Germany, was brought to the United States by Niels Bohr in January 1939. Since its discovery, the United States, and the world for that m…
1965 · 核能 · PREVIOUS ARTICLENational Academy of Sciences: Abstracts of Papers Presented at the Autumn Meeting, Seattle, Washington, 11-13 October 1965…