Investigation of the close solvation of ions in heavy water by the magnetochemical method

Solvation of Li+, Be2+, Na+, Mg2+, and Al3+ ions has been studied in binary mixtures with dimethyl sulphoxide, dimethylformamide, acetonitrile and water, and in ternary mixtures of the organic solvents with water. The CNDO/2 quantum chemical method was used to calculate the energies of solvation, molecular structures and charge distributions for the complexes acetonitrile...ion (1:1, 2:1, 4:1), dimethyl sulphoxide...ion (1:1), dimethylformamide...ion (1:1), and acetonitrile (dimethyl sulphoxide, dimethylformamide)...ion...water (1:1:1).

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Carbon-13 and nitrogen-14 NMR spectra of 1-(substituted phenyl)pyridinium salts

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19802766 ◽

1980 ◽

Vol 45 (10) ◽

pp. 2766-2771 ◽

Cited By ~ 8

Author(s):

Antonín Lyčka

Keyword(s):

Heavy Water ◽

Nmr Spectra ◽

Chemical Shifts ◽

Coupling Constants ◽

Pyridinium Salts ◽

Nmr Signals ◽

C Nmr

The 13C and 14N NMR spectra of 1M solutions of 1-(substituted phenyl)pyridinium salts (4-CH3, 4-OCH3, H, 4-Cl, 4-Br, 4-I, 3-NO2, 4-NO2, 2,4-(NO2)2 (the 13C NMR only)) have been measured in heavy water at 30 °C. The 13C and 14N chemical shifts, the 1J(CH) coupling constants, some 3J(CH) coupling constants, and values of half-widths Δ 1/2 of the 14N NMR signals are given. The 13C chemical shifts of C(4) correlate with the σ0 constants (δC(4) = (1.79 ± 0.097) σ0 + (147.67 ± 0.041)), whereas no correlation of the nitrogen chemical shifts with the σ constants has been found. The half-widths Δ 1/2 correlate with the σ0 constants (Δ 1/2 = (76.2 ± 4.9) σ0 + (106.4 ± 2.2)) except for 1-phenylpyridinium chloride.

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Tailoring neutron beam properties by target-moderator-reflector optimisation

Journal of Neutron Research ◽

10.3233/jnr-210016 ◽

2021 ◽

pp. 1-16

Author(s):

Paul Zakalek ◽

Jingjing Li ◽

Sarah Böhm ◽

Ulrich Rücker ◽

Jörg Voigt ◽

...

Keyword(s):

Neutron Beam ◽

Heavy Water ◽

Neutron Production ◽

Neutron Sources ◽

Light Water ◽

Cold Neutrons ◽

Efficient Coupling ◽

Borated Polyethylene ◽

Compact Design ◽

Neutronic Performance

Compact accelerator-driven neutron sources allow to operate multiple optimised target-moderator-reflector (TMR) units adapted to the requirements of the respective instruments. The compact design of the TMR units allows an efficient coupling of neutron production, neutron moderation and extraction, but requires a novel way of optimisation. The neutronic performance of different TMR units based on polyethylene, heavy water and a mixture of heavy and light water moderators together with Pb and Be reflectors and a borated polyethylene absorber is discussed. Extraction channels for thermal and cold neutrons are investigated regarding the energy and time spectra.

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