Tunnelling splitting patterns in some partially deuterated water trimers

2021 ◽  
Vol 23 (7) ◽  
pp. 4240-4254
Author(s):  
Mihael Eraković ◽  
Marko T. Cvitaš
Keyword(s):  
Deuterated Water ◽  
Water Trimer ◽  
Mixed Water

First characterization of the tunnelling splitting pattern in mixed water trimer isotopomers via the dynamics of flips and bifurcations.

Terahertz vibration–rotation-tunneling (VRT) spectroscopy of the d6-water trimer: Complete characterization of the 2.94THz torsional band (kn=±21←00)

2006 ◽  
Vol 423 (4-6) ◽  
pp. 344-351 ◽  
Author(s):  
Jia-xiang Han ◽  
Lynelle K. Takahashi ◽  
Wei Lin ◽  
Eddy Lee ◽  
Frank N. Keutsch ◽  
...  
Keyword(s):  
Complete Characterization ◽  
Water Trimer ◽  
Vibration Rotation

Quantitative characterization of the water trimer torsional manifold by terahertz laser spectroscopy and theoretical analysis. II. (H2O)3

1999 ◽  
Vol 111 (17) ◽  
pp. 7789-7800 ◽  
Author(s):  
Mac G. Brown ◽  
Mark R. Viant ◽  
Ryan P. McLaughlin ◽  
Christy J. Keoshian ◽  
Ernest Michael ◽  
...  
Keyword(s):  
Theoretical Analysis ◽  
Laser Spectroscopy ◽  
Quantitative Characterization ◽  
Water Trimer

Food availability for sprat larvae in the Irish Sea

1992 ◽  
Vol 72 (4) ◽  
pp. 821-834 ◽  
Author(s):  
S. H. Coombs ◽  
J. H. Nichols ◽  
D. V. P. Conway ◽  
S. Milligan ◽  
N. C. Halliday
Keyword(s):  
Water Column ◽  
Food Availability ◽  
Irish Sea ◽  
Coastal Regions ◽  
Sprattus Sprattus ◽  
Modal Abundance ◽  
The Irish Sea ◽  
Mixed Water ◽  
Eggs And Larvae

The distribution of larvae of sprat (Sprattus sprattus) is described in relation to feeding conditions in the Irish Sea. Larvae were most abundant towards the coastal margins. Relatively few were taken in the mixed water of the central Irish Sea. Preferred food organisms were also more abundant in coastal regions. Both sprat eggs and larvae, and microplankton, were more dispersed down the water column when it was fully mixed than when stratified. Characterization of food availability for larvae, as peak (modal) abundance down the water-column, is shown to be related to the degree of stratification.

Structural Systematics of Rare Earth Complexes. X (‘Maximally’) Hydrated Rare Earth Acetates

1999 ◽  
Vol 52 (6) ◽  
pp. 437 ◽  
Author(s):  
Cameron J. Kepert ◽  
Lu Wei-Min ◽  
Peter C. Junk ◽  
Brian W. Skelton ◽  
Allan H. White
Keyword(s):  
Aqueous Solution ◽  
Acetic Acid ◽  
Rare Earth ◽  
Polymeric Form ◽  
Degree Of Hydration ◽  
Trivalent Rare Earth ◽  
Geometrical Change ◽  
A Chain ◽  
Mixed Water

Extension/augmentation of preexisting work carried out in respect of room-temperature single-crystal X-ray structural characterization of trivalent rare earth acetates, crystallized as ‘maximal’ hydrates, Ln(ac)3.x H2O, from aqueous solution under local ambience, suggests the following array to be prevalent: For Ln = La(-)Pr: triclinic P 1 sesquihydrate, i.e. x = 1½, a ≈ 13·4, b ≈ 10·1, c ≈ 8·6 Å, α ≈ 75·6, β ≈ 103·8, γ ≈ 92·8°, Z = 4 mononuclear f.u., conventional R on |F| for Ln = La, Ce, here, being 0·043, 0·058 for No 3199, 4442 independent ‘observed’ (I > 3σ(I)) diffractometer reflections respectively; the complexes have the form of a two-dimensional polymer, in the ac plane, the dominant motif being a chain of lanthanoid atoms of two types linked by acetate bridges along a ... Ln(1)Ln(2)Ln(2)Ln(1)Ln(1)Ln(2) ... with further acetates cross-linking the Ln(1) in the c dimension. For Ln = (Ce(-))Nd: monoclinic P 21/c monohydrate, a ≈ 8·4, b ≈ 8·0, c ≈ 15·0 Å, β ≈ 94°, Z = 4 mononuclear f.u., for the present determinations R were 0·024, 0·044 for No 2019, 2600, the structure being a one-dimensional polymeric form with acetate bridges. For Ln = Sm(-)Lu, (i.e. implicitly with intermediate Ln): triclinic P1 tetrahydrate, a ≈ 10·4, b ≈ 9·2, c ≈ 8·8 Å, α ≈ 118, β ≈ 114, γ ≈ 92°, Z = 2 mononuclear f.u., R were 0·035, 0·030 for No 4583, 4678, the complexes being acetate-bridged dimers. It is of interest that, through the three series, the variation in the degree of hydration is not monotonic. Determinations are also recorded for a pair of crystalline compounds obtained during the attempted crystallization of europium(III) acetate hydrate from aqueous solution acidified with acetic acid (Hac), supporting their formulation as entailing the formation of mixed water/acetic acid solvates Eu(ac)3.2H2O.Hac and Eu(ac)3.H2O.2½Hac, i.e. [Eu2(ac)6(OH2)4].2Hac and [Eu2(ac)6(OH2)2(Hac)2].3Hac with common binuclear cores in which a pair of unidentate water molecule ligands in the former is replaced by a pair of unidentate acetic acid ligands in the latter with relatively minor geometrical change. The former array is rhombohedral R3, a 26·865(7), c 10·328(3) Å (hexagonal setting), Z = 9 binuclear units, isomorphous with the previously reported samarium analogue, and the latter triclinic P1, a 14·131(5), b 8·919(4), c 8·582(3) Å, α 65·41(3), β 84·72(3), γ 84·27(3)°, Z = 1 binuclear unit, R 0·046, 0·051 for No 1700, 2553. An interesting double salt, trisodium hexakis(acetato)ytterbate(III) tetrahydrate, Na3[Yb(ac)6].4H2O, is monoclinic, C2/c, a 13·139(3), b 13·936(2), c 26·030(2) Å , β 91·10(1)°, Z = 8, R 0·053 for No 3467. The eight-coordinate (YbO8) environment is comprised of oxygen atoms from a pair of O,O′-chelating and four unidentate acetate moieties.

Morphological Characterization of Mycobacteriophage R1

1974 ◽  
Vol 32 ◽  
pp. 254-255
Author(s):  
B. L. Soloff ◽  
T. A. Rado
Keyword(s):  
Carbon Source ◽  
Stationary Phase ◽  
Growth Phase ◽  
Minimal Medium ◽  
Morphological Characterization ◽  
Logarithmic Growth Phase ◽  
Complete Lysis ◽  
Lysogenic Culture ◽  
Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

AEM analysis of crystallization in Ti-based amorphous alloys

1983 ◽  
Vol 41 ◽  
pp. 270-271
Author(s):  
A.R. Pelton ◽  
A.F. Marshall ◽  
Y.S. Lee
Keyword(s):  
Magnetic Properties ◽  
Amorphous Alloys ◽  
Amorphous Materials ◽  
Isothermal Annealing ◽  
Amorphous Matrix ◽  
Nucleation And Growth ◽  
Current Interest ◽  
Amorphous Films ◽  
Electrical And Magnetic Properties

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.

Characterization of Coherent, Ordered Precipitates in Nickel-Base Alloys

1973 ◽  
Vol 31 ◽  
pp. 144-145
Author(s):  
B. H. Kear ◽  
J. M. Oblak
Keyword(s):  
Stable Phase ◽  
Nickel Base Superalloy ◽  
Alloy 718 ◽  
Commercial Alloy ◽  
Precipitate Morphology ◽  
Continuous Precipitation ◽  
Nickel Base ◽  
Base Superalloy ◽  
Strengthening Precipitate

A nickel-base superalloy is essentially a Ni/Cr solid solution hardened by additions of Al (Ti, Nb, etc.) to precipitate a coherent, ordered phase. In most commercial alloy systems, e.g. B-1900, IN-100 and Mar-M200, the stable precipitate is Ni3 (Al,Ti) γ′, with an LI2structure. In A lloy 901 the normal precipitate is metastable Nis Ti3 γ′ ; the stable phase is a hexagonal Do2 4 structure. In Alloy 718 the strengthening precipitate is metastable γ″, which has a body-centered tetragonal D022 structure.Precipitate MorphologyIn most systems the ordered γ′ phase forms by a continuous precipitation re-action, which gives rise to a uniform intragranular dispersion of precipitate particles. For zero γ/γ′ misfit, the γ′ precipitates assume a spheroidal.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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