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We have obtained empirical laws for the variation of the Earth parameters with geologic time that are in agreement with coral fossil data obtained by Wells and Runcorn. Our model predicts that the day is lengthening at a rate of 2 ms/century at the present time. The length of the day when the Earth was formed is found to be 6 hours and the synodic month 56 days. The angular momentum of the Earth-Moon system is found to be increasing with time. The origin of the presently observed acceleration of the Moon is explained. The model predicts that the Moon is accelerating at 20.6 arc sec/cy2 at the present time.

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We have developed a model for the evolution of the Earth-Moon angular momenta, energy dissipation and tidal torque valid for the entire history of the Earth-Moon system. The model is supported by present observational data.

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Abstract  

The independent isomeric yield ratio of146La and84Br in the thermal neutron fission of235U is reported for the first time with the values of 0.058±0.017 and 0.62±0.20, respectively. the yields have been determined using a fast radiochemical separation technique followed by -spectroscopy. The deduced rms angular momentum of84Br is 5.9 from the statistical model analysis and the rms angular momentum of146La is found too low to be determined.

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Abstract  

Isomer ratios for87Y,86Y and84Rb from -induced reactions on85Rb in the energy range between 20 and 60 MeV have been measured. The data show a characteristic increase followed by a decrease with the increase in bombarding energy. The fall in the isomer ratio values are explained on the basis of enhanced angular momentum depletion by the precompound particles and thereby leaving the compound system at low angular momentum states. A different reaction mechanism has been proposed for the low yield of the high spin isomer in the /, n/ reaction in85Rb.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Tran Thiep
,
Truong An
,
Nguyen Khai
,
Nguyen Vinh
,
Phan Cuong
,
I. Gangrski
,
I. Penhionzkevich
,
G. Mishinski
, and
V. Zemenhik

Abstract  

The ratio of the probabilities of population of the isomeric and ground states, so called the isomeric ratio is closely connected to the angular momentum of the initial fission fragments that is dissipated at the later stages of gamma ray cascade. This ratio also provides important information on the nuclear level structure as well as the nuclear reaction mechanism involved. In this work, the isomeric ratio in fission fragment 135Xe from photofission of 233U induced by 23.5 MeV bremsstrahlung has been determined by the method that uses inert gaseous flow. The results have been discussed and compared with that of other authors.

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Abstract  

The fractional cumulative yields (FCY) of133mTe and133gTe in the spontaneous fission of252Cf were measured for the first time by a radiochemical method. The values ofFCY are 0.533±0.014 and 0.291±0.042 for133mTe and133gTe, respectively. The isomeric state to ground state fractional independent yield (FIY) ratio of133Te,R, was found to be 3.5. The root-mean-square angular momentum of the primary fragment corresponding to the fission product133Te, Jr.m.s.=8.8h, was estimated according to a simple one-parameter statistical model. The fractional cumulative yields from this work together with other literature data in the mass region A=131–141 are compared with the normal yields given by the empiricalZ p model by Whhl. It suggests that both theN=82 neutrons shell and nucleus pairing effects are not apparent for the spontaneous fission of252Cf.

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. – Ghil , M. – Marcus , S. L. ( 1991 ): Extra Tropical Aspects of the 40-50 Day Oscillation in Length-of-Day and Atmospheric Angular Momentum . Journal of Geophysical Research , 96 ( 22 ): 643 – 658

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of rotor, a and a ′ are the axial and the tangential induction factors respectively. Fig. 1. Velocities and forces on a blade element In the momentum theory, the application of axial momentum conservation and angular momentum conservation gives

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between two or more subatomic particles creates a mutual correlative relation (a ‘quantum correlation’) between their quantum states (defined by spin and orbital angular momentum), which in turn gives rise to the phenomenon of quantum nonlocality, which

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