scholarly journals Reversible Electrochemical Intercalation and Deintercalation of Fluoride Ions into Host Lattices with Schafarzikite-Type Structure

ChemistryOpen ◽  
2018 ◽  
Vol 7 (8) ◽  
pp. 617-623 ◽  
Author(s):  
Mohammad Ali Nowroozi ◽  
Benjamin de Laune ◽  
Oliver Clemens
Keyword(s):  
Type Structure ◽  
Fluoride Ions ◽  
Electrochemical Intercalation ◽  
Host Lattices

Hydrogen-Bonded Urea–Anion Host Lattices. 6. New Inclusion Compounds of Urea with Tetra-n-propylammonium Halides

1998 ◽  
Vol 54 (2) ◽  
pp. 180-192 ◽  
Author(s):  
Q. Li ◽  
T. C. W. Mak
Keyword(s):  
Crystal Structure ◽  
Three Dimensional ◽  
Host Lattice ◽  
Chloride Ions ◽  
Fluoride Ions ◽  
Space Group ◽  
X Ray Crystallography ◽  
Planar Arrays ◽  
Host Lattices ◽  
Channel Type

New inclusion complexes tetra-n-propylammonium fluoride–urea–water (2/7/3), 2(n-C3H7)4N+F−.7(NH2)2CO.3H2O (1), tetra-n-propylammonium chloride–urea (1/2), (n-C3H7)4N+Cl−.2(NH2)2CO (2), tetra-n-propylammonium chloride–urea (1/3), (n-C3H7)4N+Cl−.3(NH2)2CO (3), tetra-n-propylammonium bromide–urea–water (1/3/1), (n-C3H7)4N+Br−.3(NH2)2CO.H2O (4), and tetra-n-propylammonium iodide–urea–water (1/3/1), (n-C3H7)4N+I−.3(NH2)2CO.H2O (5), have been prepared and characterized by X-ray crystallography. Crystal data, Mo Kα radiation: (1), space group P21/c, Z = 4, a = 8.560 (2), b = 16.301 (3), c = 37.004 (7) Å, β = 92.31 (3)°, R F = 0.075 for 3945 observed data; (2), space group P21/n, Z = 4, a = 9.839 (2), b = 15.160 (3), c = 14.583 (3) Å, β = 108.82 (3)°, R F = 0.058 for 1770 observed data; (3), space group P21/c, Z = 4, a = 9.866 (2), b = 16.274 (3), c = 15.277 (3) Å, β = 103.36 (3)°, R F = 0.060 for 2272 observed data; (4), space group P1¯, Z = 2, a = 8.857 (2), b = 10.639 (2), c = 15.115 (3) Å, α = 88.01 (3), β = 75.02 (3), γ = 66.72 (3)°, R F = 0.064 for 2694 observed data; (5), space group P1¯, Z = 2, a = 9.045 (2), b = 10.781 (2), c = 15.169 (3) Å, α = 87.98 (3), β = 76.00 (3), γ = 65.73 (3)°, R F = 0.052 for 4973 observed data. In the crystal structure of (1) an alternate crisscross arrangement of urea ribbons, which are cross-bridged by other urea molecules, water molecules and fluoride ions, generates a three-dimensional host lattice containing an open-channel system running parallel to the b axis, with the (n-C3H7)4N+ cations accommodated in a zigzag column within each channel. In the crystal structure of (2) the cations are sandwiched between puckered layers resulting from parallel urea ribbons that are cross-bridged by chloride anions. In (3) the (n-C3H7)4N+ cations are accommodated in a channel-type host lattice built of planar arrays of twisted ribbons constructed from three independent urea molecules, which are cross-linked by bridging chloride ions. Complexes (4) and (5) are isomorphous with the same channel host framework built of parallel corrugated urea layers that are interlinked by cyclic (H2O.X −)2 tetramers.

LaSrMnO4: Reversible Electrochemical Intercalation of Fluoride Ions in the Context of Fluoride Ion Batteries

2017 ◽  
Vol 29 (8) ◽  
pp. 3441-3453 ◽  
Author(s):  
Mohammad Ali Nowroozi ◽  
Kerstin Wissel ◽  
Jochen Rohrer ◽  
Anji Reddy Munnangi ◽  
Oliver Clemens
Keyword(s):  
Fluoride Ion ◽  
Fluoride Ions ◽  
Electrochemical Intercalation

Tuning the adsorption behaviour of β-structure chitosan by metal binding

2018 ◽  
Vol 15 (5) ◽  
pp. 267 ◽  
Author(s):  
Chunyan Ma ◽  
Fang Li ◽  
Caihua Wang ◽  
Miao He ◽  
Chensi Shen ◽  
...  
Keyword(s):  
Metal Complex ◽  
Metal Ions ◽  
Metal Complexes ◽  
Metal Binding ◽  
Intermolecular Forces ◽  
Polymer Chains ◽  
Type Structure ◽  
Enhancement Effect ◽  
Fluoride Ions ◽  
Freundlich Model

Environmental contextChitosan is an abundant natural component of marine life with potential applications as an adsorbant material for pollutants. We investigate the binding behaviour of chitosan, and show that the β-type structure readily chelates metal ions leading to enhanced adsorption of anionic pollutants in the chitosan-metal complex. The results are highly relevant to the removal of anionic organic pollutants from water. AbstractChitosan, which is commonly extracted from squid pens of the Loligo genus, has a β-type structure. Chitosan has potential application to the adsorption of pollutants but has received little study. We investigate the adsorption ability of β-structure chitosan as well as FeIII and AlIII chitosan-metal complexes. Pristine β-chitosan shows lower adsorption abilities for dye, CrVI and fluoride ions compared with those for α-chitosan, mainly owing to having fewer –NH3+ groups on its surface. However, the anionic pollutant adsorption efficiency of β-chitosan is clearly enhanced when chelated with metal ions. A β-structure chitosan-Fe-Al complex displayed adsorption capacities of 621.45 mg g−1 and 144.53 mg g−1 for Acid Red 73 dye and fluoride ions, respectively, according to the fitted Langmuir–Freundlich model; and of more than 173.03 mg g−1 for CrVI, according to the Freundlich model. These values are much higher than those observed for α-structure chitosan-metal complexes. This enhancement effect on the sorptive behaviour of β-chitosan can be attributed to its loose structure. The polymer chains of β-chitosan are arranged in parallel with relatively weak intermolecular forces, which allows them to easily chelate metal ions. Anionic pollutants can then be efficiently adsorbed by the chelated metal ions in the chitosan-metal complex if the electrostatic attraction of the –NH3+ groups is weak. This investigation provides a better understanding of β-chitosan-based adsorbents for application to anionic pollutant adsorption and removal.

New semiconducting compounds of diamond type structure

Physica ◽  
1954 ◽  
Vol 3 (7-12) ◽  
pp. 1107-1109 ◽  
Author(s):  
C GOODMAN ◽  
R DOUGLAS
Keyword(s):  
Type Structure ◽  
Semiconducting Compounds ◽  
Diamond Type

Study of Natural Minerals of U-Ryrochlore-Type Structure as Analogues of Plutonium Ceramic Waste-form

2002 ◽  
Vol 713 ◽  
Author(s):  
Roman V. Bogdanov ◽  
Yuri F. Batrakov ◽  
Elena V. Puchkova ◽  
Andrey S. Sergeev ◽  
Boris E. Burakov
Keyword(s):  
Chemical Shifts ◽  
Pyrochlore Structure ◽  
Type Structure ◽  
Waste Form ◽  
X Ray ◽  
Ceramic Waste ◽  
Natural Minerals ◽  
The Us ◽  
Pyrochlore Type

ABSTRACTAt present, crystalline ceramic based on titanate pyrochlore, (Ca,Gd,Hf,Pu,U)2Ti2O7, is considered as the US candidate waste form for the immobilization of weapons grade plutonium. Naturally occuring U-bearing minerals with pyrochlore-type structure: hatchettolite, betafite, and ellsworthite, were studied in orders to understand long-term radiation damage effects in Pu ceramic waste forms. Chemical shifts (δ) of U(Lδ1)– and U(Lβ1) – X-ray emission lines were measured by X-ray spectrometry. Calculations were performed on the basis of a two-dimensional δLá1- and δLδ1- correlation diagram. It was shown that 100% of uranium in hatchettolite and, probably, 95-100% of uranium in betafite are in the form of (UO2)2+. formal calculation shows that in ellsworthite only 20% of uranium is in the form of U4+ and 80% of the rest is in the forms of U5+ and U6+. The conversion of the initial U4+ ion originally occurring in the pyrochlore structure of natural minerals to (UO2)2+ due to metamict decay causes a significant increase in uranium mobility.

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