1,955 research outputs found
Equilibration dynamics and isospin effects in nuclear reactions
We discuss equilibration times and isospin effect for various quantities in
low-energy heavy-ion reactions. These include equilibration of mass, isospin,
and total kinetic energy (TKE) in quasifission and deep-inelastic reactions.
The calculations are performed using the time-dependent Hartree-Fock theory.
The influence of shell effects on the equilibration times are also discussed in
the context of theoretical and experimental results.Comment: 7 pages, 5 figures, proceedings of IWM-EC201
Microscopic DC-TDHF study of heavy-ion potentials and fusion cross sections
We study heavy-ion fusion reactions at energies near the Coulomb barrier, in
particular with neutron-rich radioactive ion beams. Dynamic microscopic
calculations are carried out on a three-dimensional lattice using the
Density-Constrained Time-Dependent Hartree-Fock (DC-TDHF) method. New results
are presented for the Sn+Ca system which are compared to
Sn+Ca studied earlier. Our theoretical fusion cross-sections
agree surprisingly well with recent data measured at HRIBF. We also study the
near- and sub-barrier fusion of O on C which is important to
determine the composition and heating of the crust of accreting neutron stars.Comment: Talk given by . Volker E. Oberacker at the 11th International
Conference on Nucleus-Nucleus Collisions (NN2012), San Antonio, Texas, USA,
May 27-June 1, 2012. To appear in the NN2012 Proceedings in Journal of
Physics: Conference Series (JPCS
Successes and challenges of under-five child mortality reduction in West Africa
Background: Under-five mortality rate is an important index for assessing achievements by countries and thus its targeted reduction is adopted as benchmark towards realizing the Millennium Development Goal number4 by 2015. With less than 24 months to the deadline, West Africa still contributes significantly to the global burden of child mortality, with over half of the deaths caused by infections.Objective: To review the successes and challenges of reducingunder-five mortality in West Africa.Sources: A search was made in Pub Med and Google Scholar using the key words: Under-five, Children, Mortality, West Africa, Successes, Progress, Achievements and Challenges. Relevant publications and reports availableat WHO, UNICEF and UN websites were also consulted. Tables and charts were drawn from relevant data for West African Countries obtained from these sources using Microsoft® Excel® for Mac 2011 Version 14.1.0(110310).Results: Although significant under-five death reductions have been recorded in countries of West Africa between 1990 and 2012, the reduction falls far short of the expected targets and infections still remain the leading causes of death. In spite of a fivefold rise of average annual rate of reduction of under-five deaths compared to a 3-fold rise of the global average and a 49.7% reduction in under-five mortality rate, the sub-region trails behind other parts of Africa. While only Liberia achieved the MDG 4 target, Niger, Cape Verde, Gambia, Guinea and Burkina Faso are on track. Nigeria’s huge child population, high under-five mortality burden and slow reduction, weighs down the sub-region’s averages. Neonatal death proportions are rising, with four countries ranking amongst the world’s top ten. With less than 24 months left, the likelihood of achieving the reduction targets for under-five mortality in most of the countries in the sub-region by the end of 2015 remains a mirage.Conclusion: Numerous daunting challenges have contributed to slow the pace of under-five death reduction in West Africa. Countries in the sub-region need to address their challenges while scaling up proven interventions to accelerate progress towards further reductions of under-five deaths.Key words: Children, under-five, mortality, West Africa, progress, successes, achievements, challenge
The Effect of Extensive Reading and Learning Style on Academic Writing Competency of Semester Five Students of STKIP Hamzanwadi Selong
The present study aimed at investigating the effect of extensive reading and learning style on students' academic writing competency. This study used population sample, in the sense that all students in the population (60 students) were taken as sample. The experimental group and the control one were determined through a random sampling. The experimental study employed a 2 x 2 factorial post test only control group design. The instruments used to collect the data were an academic writing test and learning style questionnaires. The data were analyzed by using Two-Way ANOVA Statistic and Tukey Test. The study showed that there was no significant difference in academic writing competency between students who are assigned to do extensive reading and those who are not. However, extensive reading and learning style were found to be interactively influence students academic writing competency, revealing that there was a significant difference between the writing competency of independent students taught using extensive reading and those who are not. The implication is that the students with independent learning style effectively improve their writing competency through extensive reading activity
Perencanaan Pipa Transmisi Sumber Air Baku Sungai Bekuan Bagi Penduduk Kecamatan Lembah Bawang
Analysis begins with the planning phase to determine the water quality of the design of water treatment, after the calculation of flood discharge analysis, followed by analysis of population projections for the next 20 years. After Knowing Population, conducted a needs assessment of the community water valley onions and quantity of water which is owned by River raw water source clot. Recently tested the reliability of the source of raw water for then all the data is processed using Epanet Program. Of Air Quality Test Results in laboratory Health Office dr. Sudarso, Pontianak meragun sirin known that water is still very clean and does not require water treatment. Followed by Analysis Debit Flood Plan using HSS method Snyder is known that the maximum discharge clot River Water Source for the return period of 20 years is 8.7602 liters / sec while the clean water needs at peak hours of 12.7752 liters / sec. Furthermore, from the analysis of the pipeline which will be used using 2.0 Epanet program planned transmission network using HDPE pipe with pipe diameter Ø 150 mm with a distance of 3283 mm
Neutron Transfer Dynamics and Doorway to Fusion in Time-Dependent Hartree-Fock Theory
We analyze the details of mass exchange in the vicinity of the Coulomb
barrier for heavy-ion collisions involving neutron-rich nuclei using the
time-dependent Hartree-Fock (TDHF) theory. We discuss the time-dependence of
transfer and show that the potential barriers seen by individual
single-particle states can be considerably different than the effective barrier
for the two interacting nuclei having a single center-of-mass. For this reason
we observe a substantial transfer probability even at energies below the
effective barrier.Comment: 6 pages, 9 figure
Effect of Pauli repulsion and transfer on fusion
The effect of the Pauli exclusion principle on the nucleus-nucleus bare
potential is studied using a new density-constrained extension of the
Frozen-Hartree-Fock (DCFHF) technique. The resulting potentials exhibit a
repulsion at short distance. The charge product dependence of this Pauli
repulsion is investigated. Dynamical effects are then included in the potential
with the density-constrained time-dependent Hartree-Fock (DCTDHF) method. In
particular, isovector contributions to this potential are used to investigate
the role of transfer on fusion, resulting in a lowering of the inner part of
the potential for systems with positive Q-value transfer channels.Comment: Proceedings of an invited talk given at FUSION17, Hobart, Tasmania,
AU (20-24 February, 2017
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