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Journal Articles

The Joint evaluated fission and fusion nuclear data library, JEFF-3.3

Plompen, A. J. M.*; Cabellos, O.*; De Saint Jean, C.*; Fleming, M.*; Algora, A.*; Angelone, M.*; Archier, P.*; Bauge, E.*; Bersillon, O.*; Blokhin, A.*; et al.

European Physical Journal A, 56(7), p.181_1 - 181_108, 2020/07

 Times Cited Count:73 Percentile:99.41(Physics, Nuclear)

The Joint Evaluated Fission and Fusion nuclear data library 3.3 is described. New evaluations for neutron-induced interactions with the major actinides $$^{235}$$U, $$^{238}$$U and $$^{239}$$Pu, on $$^{241}$$Am and $$^{23}$$Na, $$^{59}$$Ni, Cr, Cu, Zr, Cd, Hf, W, Au, Pb and Bi are presented. It includes new fission yileds, prompt fission neutron spectra and average number of neutrons per fission. In addition, new data for radioactive decay, thermal neutron scattering, gamma-ray emission, neutron activation, delayed neutrons and displacement damage are presented. JEFF-3.3 was complemented by files from the TENDL project. The libraries for photon, proton, deuteron, triton, helion and alpha-particle induced reactions are from TENDL-2017. The demands for uncertainty quantification in modeling led to many new covariance data. A comparison between results from model calculations using the JEFF-3.3 library and those from benchmark experiments for criticality, delayed neutron yields, shielding and decay heat, reveals that JEFF-3.3 is excellent for a wide range of nuclear technology applications, in particular nuclear energy.

Journal Articles

The Existence of memory effect on hydrogen ordering in ice; The Effect makes ice attractive

Arakawa, Masashi*; Kagi, Hiroyuki; Fernandez-Baca, J. A.*; Chakoumakos, B.*; Fukazawa, Hiroshi

Geophysical Research Letters, 38, p.L16101_1 - L16101_5, 2011/08

 Times Cited Count:11 Percentile:36.14(Geosciences, Multidisciplinary)

The existence of ferroelectric ice XI with ordered hydrogen in space becomes of interest in astronomy and physical chemistry because of the strong electrostatic force. However, the influence was believed to be limited because it forms at narrow temperature range. From neutron diffraction experiments, we found that small hydrogen-ordered domains exist at significantly higher temperature and the domains induce the growth of "bulk" ice XI. The small ordered domain is named "memory" of hydrogen ordered ice because it is the residual structure of ice XI. Since the memory exists up to at least 111 K, most of ices in the solar system are hydrogen ordered and may have ferroelectricity. The small hydrogen-ordered domains govern the cosmochemical properties of ice and evolution of icy grains in the universe.

Journal Articles

Structure and properties of ferroelectric ice

Fukazawa, Hiroshi; Arakawa, Masashi*; Kagi, Hiroyuki; Yamauchi, Hiroki; Chakoumakos, B. C.*; Fernandez-Baca, J. A.*

Physics and Chemistry of Ice 2010, p.421 - 428, 2011/03

Whether or not ice in the universe exists as ferroelectric is a question that has attracted interest in astrophysics and physical chemistry, because long-range electrostatic forces, caused by the ferroelectricity, might be an important factor for materials evolution and hydrogen bonding. From neutron diffraction and scattering measurements, we have studied ice with impurities, such as potassium, sodium and lithium, that acted as a catalyst. Time-resolved diffraction experiments show that ferroelectric ice XI with hydrogen-ordered arrangement nucleates and grows with time for about 5 days. We found that the doped ice that has once been converted to ice XI is a stronger ferroelectric ice than that has never been converted. We also show the existence of the ferroelectric ice under high-pressure and its formation from compressed amorphous ice.

Journal Articles

Neutron diffraction study of hydrogen-ordered ice XI; Annealing effect and memory effect

Arakawa, Masashi*; Kagi, Hiroyuki; Fernandez-Baca, J. A.*; Chakoumakos, B. C.*; Fukazawa, Hiroshi

Physics and Chemistry of Ice 2010, p.329 - 338, 2011/03

We measured neutron diffraction profiles of KOD, NaOD, LiOD, Ca(OD)$$_{2}$$, and ND$$_{3}$$-doped ices. Ice XI, which is a hydrogen-ordered phase of normal ice (ice Ih), was observed in the KOD and NaOD-doped ices although Ca(OD)$$_{2}$$ and ND$$_{3}$$-doped ice did not transformed to ice XI. The mass fraction of ice XI to that of the doped ice ($$f$$) was estimated using Rietveld analysis for each doped ice. The $$f$$ value of the doped ice, which had once experienced being ice XI, was larger than that of the doped ice, which had never experienced being ice XI. The large $$f$$ value of the doped ice indicates that small hydrogen-ordered domains remained above the transition temperature between ice XI and Ih. Our results suggest that large amounts of ice on icy bodies in our solar system can transform to ice XI. In this paper, we discussed the existence of the small hydrogen-ordered domains in space and the evolution of icy grain.

Journal Articles

Existence of ferroelectric ice on planets; A Neutron diffraction study

Fukazawa, Hiroshi; Hoshikawa, Akinori*; Chakoumakos, B. C.*; Fernandez-Baca, J. A.*

Nuclear Instruments and Methods in Physics Research A, 600(1), p.279 - 281, 2009/02

 Times Cited Count:12 Percentile:65.67(Instruments & Instrumentation)

We measured time-resolved neutron powder diffraction of ices doped with very small amounts of some catalysts using the wide-angle neutron diffractometer (WAND) at the High Flax Isotope Reactor (HFIR) in Oak Ridge, Tennessee. We succeeded in making ferroelectric ice, which prepared at high pressures (0.2 and 0.4 GPa), in a 60 to 75 K temperature range over tens hours. Neutron diffraction experiments confirmed the existence of a large ferroelectric structure in the sample. Therefore, thick surface (about 500 Km) of ferroelectric ice may exist on cold icy bodies, such as, Pluto and Kuiper Belt Objects (KBO). It suggests that about 70% of Pluto body is ferroelectric ice. Future telescope or planetary probe will be able to detect the huge ferroelectric-ice mass. In this symposium we report recent results at the HFIR and our future plan using higher intensity neutron beam.

Journal Articles

Existence of ferroelectric ice in the universe

Fukazawa, Hiroshi; Hoshikawa, Akinori; Ishii, Yoshinobu; Chakoumakos, B. C.*; Fernandez-Baca, J. A.*

Astrophysical Journal, 652(1, Part2), p.L57 - L60, 2006/11

 Times Cited Count:41 Percentile:70.81(Astronomy & Astrophysics)

Whether ferroelectric ice, named ice XI, exists in a stable low-temperature phase attracts much interest. This question arose as a condensed-matter issue, and became of interest in astronomy (e.g., does ice XI exist on Pluto?) because astronomical observations identified the existence of crystalline ice in our solar system. From neutron diffraction experiments, we found the temperature conditions for the transformation of the largest fraction of ice into ice XI using the lowest level of impurity dopant. The finding of bulk crystal of ordered structure firmly supports that ice XI is stable. This suggests the existence of naturally occurring ice XI at a narrow temperature range (57-66 K) in our solar system.

Journal Articles

CO$$_2$$ hydrate; Synthesis, composition, structure, dissociation behavior, and a comparison to structure I CH$$_4$$ hydrate

Circone, S.*; Stern, L. A.*; Kirby, S. H.*; Durham, W. B.*; Chakoumakos, B. C.*; Rawn, C. J.*; Rondinone, A. J.*; Ishii, Yoshinobu

Journal of Physical Chemistry B, 107(23), p.5529 - 5539, 2003/06

 Times Cited Count:133 Percentile:94.13(Chemistry, Physical)

no abstracts in English

Journal Articles

Neutron diffraction study of structure I and structure II trimethylene oxide clathrata deuterate

Rondinone, A. J.*; Chakoumakos, B. C.*; Rawn, C. J.*; Ishii, Yoshinobu

Journal of Physical Chemistry B, 107(25), p.6046 - 6050, 2003/06

 Times Cited Count:19 Percentile:48.14(Chemistry, Physical)

no abstracts in English

Journal Articles

Structure and thermal expansivity of tetrahydrofuran deuterate determined by neutron powder diffraction

Jones, C. Y.*; Marshall, S. L.*; Chakoumakos, B. C.*; Rawn, C. J.*; Ishii, Yoshinobu

Journal of Physical Chemistry B, 107(25), p.6026 - 6031, 2003/03

 Times Cited Count:37 Percentile:69.56(Chemistry, Physical)

no abstracts in English

Journal Articles

The Use of rigid body constraints in Rietveld refinements of neutron diffraction data of clathrate hydrates

Chakoumakos, B. C.*; Rawn, C. J.*; Rondinone, A. J.*; Marshall, S. L.*; Stern, L. A.*; Circone, S.*; Kirby, S. H.*; Jones, C. Y.*; Toby, B. H.*; Ishii, Yoshinobu

Proceedings of 4th International Conference on Gas Hydrates (ICGH-4), p.655 - 658, 2002/05

no abstracts in English

Journal Articles

Neutron powder diffraction studies as a function of temperature of structure II hydrate formed from a methane + ethane gas mxture

Rawn, C. J.*; Rondinone, A. J.*; Chakoumakos, B. C.*; Marshall, S. L.*; Stern, L. A.*; Circone, S.*; Kirby, S. H.*; Jones, C. Y.*; Toby, B. H.*; Ishii, Yoshinobu

Proceedings of 4th International Conference on Gas Hydrates (ICGH-4), p.595 - 598, 2002/05

no abstracts in English

Journal Articles

Neutron diffraction study of structure I and structure II trimethylene oxide clathrate deuterate

Rondinone, A. J.*; Chakoumakos, B. C.*; Rawn, C. J.*; Ishii, Yoshinobu

Proceedings of 4th International Conference on Gas Hydrates (ICGH-4), p.625 - 629, 2002/05

no abstracts in English

Oral presentation

Nucleation and growth of ice XI; Study suggests the existence of ferroelectric ice in the Universe

Fukazawa, Hiroshi; Hoshikawa, Akinori*; Chakoumakos, B.*; Fernandez-Baca, J. A.*

no journal, , 

From neutron powder-diffraction experiments, we have studied the growth process of ferroelectric ice XI with deuteron-ordered arrangements. We measured time-resolved neutron diffraction of compressed KOD or NaOD doped D$$_{2}$$O-ice. We observed the growth of ice XI at 58 $$sim$$ 74 K. The mass fraction f (the ratio of mass of ice XI to that of the doped ice) linearly increased with time for about 5 days. The de-transformed ice Ih, obtained after warming above the transition temperature of 76 K, retransformed to ice XI at 60 $$sim$$ 66 K. The observed increase of f with time is in good agreement with the nucleation process of the ordering and the constant growth of the ordered domain. The results suggest that large quantities of ice on cold icy bodies (such as Pluto and Charon) in our solar system are able to transform to ice XI, which may be detectable by space telescope and planetary exploration.

Oral presentation

Neutron diffraction study of ice under high pressure and low temperature

Fukazawa, Hiroshi; Hoshikawa, Akinori*; Chakoumakos, B.*; Fernandez-Baca, J. A.*

no journal, , 

We performed long-duration annealing experiments on ice Ih and reported that ferroelectric ice constantly grew below 76 K. The hydrogen ordering was repeated. The detailed analysis of ice with sodium hydroxide also showed the same ordering. The results support our initial proposal of the existence of ferroelectric ice in the Universe.

Oral presentation

Ferroelectric ice and hydrogen-ordered clathrate in our solar system

Fukazawa, Hiroshi; Hoshikawa, Akinori*; Chakoumakos, B.*; Fernandez-Baca, J. A.*

no journal, , 

We performed long-duration annealing experiments on ice Ih and reported that ferroelectric ice constantly grew below 76 K. The hydrogen ordering was repeated. The detailed analysis of ice with sodium hydroxide also showed the same ordering. The results support our initial proposal of the existence of ferroelectric ice in the Universe.

Oral presentation

Growth of ferroelectric ice XI doped with alkali metal hydroxide observed using neutron diffraction

Arakawa, Masashi*; Komatsu, Kazuki*; Iizuka, Riko*; Kagi, Hiroyuki; Fernandez-Baca, J. A.*; Chakoumakos, B.*; Yamauchi, Hiroki; Fukazawa, Hiroshi

no journal, , 

We prepared ice XI from different kinds of alkali metal hydroxide solutions with different concentrations, and measured neutron powder diffraction at JRR-3 (Japan Atomic Energy Agency, Japan) and HFIR (Oak Ridge National Laboratory, TN, USA). Rietveld analysis was carried out for the obtained diffraction patterns using a two-phase model, which includes ices Ih and XI. The hydrogen-ordered structure in the lithium-doped ice was the same as that in the sodium-doped and potassium-doped ices. We also confirmed the optimum formation condition of ice XI for the temperature history and concentration of solution. Furthermore, our results indicate that the phase transition from ice Ih to XI occurs in the doped ice that had once been ice XI to a notably larger degree than in the doped ice that had never transformed to ice XI. We named this phenomenon memory effect of hydrogen ordering.

Oral presentation

Neutron diffraction and IR absorption studies of ice crystal; An Implication of planetary science

Arakawa, Masashi*; Kagi, Hiroyuki; Fernandez-Baca, J. A.*; Chakoumakos, B.*; Fukazawa, Hiroshi

no journal, , 

The existence of ferroelectric ice XI with ordered hydrogen in the universe becomes of interest in astronomy and physical chemistry because of the strong electric force. However, the influence seemed to be limited because it forms at narrow temperature range. From neutron diffraction experiments, we found that small hydrogen-ordered domains with ferroelectricity exist at higher temperature and the domains induce the growth of bulk ice XI. The small ordered domain is named memory of hydrogen ordered ice because it is the residual structure of ice XI.

Oral presentation

Memory of ice observed by neutron diffraction

Fukazawa, Hiroshi; Arakawa, Masashi*; Kagi, Hiroyuki; Chakoumakos, B.*; Fernandez-Baca, J. A.*

no journal, , 

From neutron diffraction experiments, we found that small hydrogen-ordered domains exist at significantly higher temperature and the domains induce the growth of bulk ice XI. The small ordered domain is named memory of hydrogen ordered ice because it is the residual structure of ice XI. Since the memory exists up to about 150 K, most of ices in the solar system are hydrogen ordered and may have ferroelectricity. The small hydrogen-ordered domains govern the cosmochemical properties of ice.

Oral presentation

Water structure in a hydrogel

Sekine, Yurina; Fukazawa, Hiroshi; Songxue, C.*; Chakoumakos, B.*; Fernandez-Baca, J. A.*

no journal, , 

no abstracts in English

Oral presentation

Structure of water and ice in poly-N,N,-dimethylacrylamide hydrogel

Sekine, Yurina; Fukazawa, Tomoko*; Yamauchi, Hiroki; Songxue, C.*; Chakoumakos, B.*; Fernandez-Baca, J. A.*; Fukazawa, Hiroshi

no journal, , 

Neutron diffraction data of deuterated poly-N,N,-dimethylacrylamide (PDMAA) hydrogel were measured at temperatures of 10 - 290 K in order to investigate the structure and properties of water in the hydrogel. Diffraction peaks observed below 270 K indicate the existence of a solid ice in the hydrogel. The positions of some peaks from the ice are lower than those in ordinary hexagonal ice (Ih). The lower shifts of the peaks indicates that the lattice constants of the c-axis in the ice are about 0.3% higher than those in ice Ih, whereas those of the a-axis are almost consist. The results show that bulk of a low-density ice crystal exists in the PDMAA hydrogel. The water molecules, which have a significant interaction with the polymer chains, play an important role in the chemical and mechanical properties of the hydrogel.

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