Accordion-like swelling of layered perovskite crystals via massive permeation of aqueous solutions into 2D oxide galleries

2015 ◽  
Vol 51 (96) ◽  
pp. 17068-17071 ◽  
Author(s):  
Yeji Song ◽  
Nobuo Iyi ◽  
Tatsumasa Hoshide ◽  
Tadashi C. Ozawa ◽  
Yasuo Ebina ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Water Content ◽  
Layered Perovskite ◽  
Tetrabutylammonium Hydroxide ◽  
Hydroxide Solution

Platelet crystals of a layered perovskite enormously swelled in a tetrabutylammonium hydroxide solution, producing unique columnar shaped crystals with a water content of >90 wt%.

Swelling of Layered Potassium Ruthenate into Nanosheet Crystallites

2008 ◽  
Vol 1148 ◽  
Author(s):  
Katsutoshi Fukuda ◽  
Hisato Kato ◽  
Wataru Sugimoto ◽  
Yoshio Takasu
Keyword(s):  
Water Content ◽  
Colloidal Suspension ◽  
Intercalation Compound ◽  
Swelling Behavior ◽  
Layered Compound ◽  
Interlayer Water ◽  
Tetrabutylammonium Hydroxide

AbstractThe swelling and exfoliation behaviors of layered potassium ruthenate and the resultant unilamellar crystallites of RuO2.10.2− with nanosheet morphology were studied. The reaction of layered H0.2RuO2.1·0.9H2O with tetrabutylammonium hydroxide (TBA+OH−) was found to be extremely sensitive to the interlayer water content. The use of highly hydrous layered protonic ruthenate was essential for obtaining direct exfoliation. The swelling behavior was also affected by the ratio of TBA+ to ion-exchangeable H+ in the layered compound. At low ratios of TBA+/H+≤1, the layered precursor scarcely exfoliated and mostly deposited as an intercalation compound. In the intermediate TBA+/H+ range, an auburn colloidal suspension containing exfoliated nanosheets was formed, while much larger ratios were less favorable for the exfoliation.

AFM-Assisted Investigation of the Corrosion Behaviour of Magnesium and AZ91 Alloys in an Ionic Liquid with Varying Water Content

2007 ◽  
Vol 60 (1) ◽  
pp. 35 ◽  
Author(s):  
Andrey Shkurankov ◽  
Sherif Zein El Abedin ◽  
Frank Endres
Keyword(s):  
Ionic Liquid ◽  
Corrosion Rate ◽  
Aqueous Solutions ◽  
Water Content ◽  
Corrosion Behaviour ◽  
Base Alloy ◽  
Saturated Calomel Electrode ◽  
Electrochemical Window ◽  
Metallic Impurities

Atomic force microscopy (AFM)-assisted corrosion measurements of poly- and microcrystalline magnesium, of AZ91D magnesium alloys, and of AZ91D alloys with defined amounts of metallic impurities (Cu, Ni, and Si) in the ionic liquid 1-butyl-3-methylimidazolium trifluoromethylsulfonate with variable water contents is reported. Whereas both magnesium and the AZ91 alloys show a tremendous corrosion in aqueous solutions, they are practically inert in the water-free ionic liquid. The apparent electrochemical window of the water-free ionic liquid on magnesium and its alloys can reach values of 10 V and more. The low corrosion rate of AZ91 alloys with metallic impurities, in any case, follows the trend in aqueous solutions: in comparison to the base alloy, the addition of nickel and silicon leads to higher corrosion rates. Upon addition of water to the ionic liquid two effects are observed. The higher the water content in the ionic liquid, the lower the corrosion potential and the higher the corrosion rate. Poly- and microcrystalline magnesium shows a surprisingly complicated corrosion behaviour, which gives rise to different processes during electrochemical polarization. As a proof-of-principle, in-situ AFM measurements were performed on the corrosion of AZ91D alloy in the ionic liquid. No corrosion products are observed at the surface in the water-free ionic liquid by in-situ AFM, even after several hours at +3 V versus a saturated calomel electrode (SCE), which indicates surface passivation in the ionic liquid.

Massive hydration-driven swelling of layered perovskite niobate crystals in aqueous solutions of organo-ammonium bases

2018 ◽  
Vol 47 (9) ◽  
pp. 3022-3028
Author(s):  
Yeji Song ◽  
Nobuo Iyi ◽  
Tatsumasa Hoshide ◽  
Tadashi C. Ozawa ◽  
Yasuo Ebina ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Layered Perovskite ◽  
Osmotic Swelling ◽  
Systematic Understanding ◽  
Layered Niobate

A systematic understanding on the osmotic swelling of layered niobate crystals using various amines is reported.

scholarly journals Formation and dissociation of synthetic hetero-double-helix complex in aqueous solutions: significant effect of water content on dynamics of structural change

RSC Advances ◽  
2019 ◽  
Vol 9 (50) ◽  
pp. 29456-29462
Author(s):  
Tsukasa Sawato ◽  
Ryosuke Yuzawa ◽  
Higashi Kobayashi ◽  
Nozomi Saito ◽  
Masahiko Yamaguchi
Keyword(s):  
Structural Change ◽  
Aqueous Solutions ◽  
Water Content ◽  
Structural Changes ◽  
Double Helix ◽  
Effect Of Water ◽  
Small Change

Significant structural changes by small change in water content from 30 to 33%.

scholarly journals One pot obtention of a tetrabutylammonium hydroxide solution for ironporphyrin-OH- interaction studies in organic solvents

Química Nova ◽  
1999 ◽  
Vol 22 (2) ◽  
pp. 277-279 ◽  
Author(s):  
Lídia S. Iwamoto ◽  
Osvaldo A. Serra ◽  
Cynthia M. C. Prado Manso ◽  
Yassuko Iamamoto
Keyword(s):  
Organic Solvents ◽  
Tetrabutylammonium Hydroxide ◽  
One Pot ◽  
Hydroxide Solution ◽  
Interaction Studies

scholarly journals THE EFFECT OF HYDROGEL DRESSING COPOLYMER POLI(VINYLPIRROLIDONE) (PVP) - k- CARRAGEENAN PREPARED BY RADIATION AND HEALING TIMES ON THE RADIUS REDUCTIONS BURN INJURIED OF WISTAR WHITE RAT

2010 ◽  
Vol 8 (2) ◽  
pp. 271-278
Author(s):  
Erizal Erizal
Keyword(s):  
Tensile Strength ◽  
Clinical Study ◽  
Aqueous Solutions ◽  
Water Absorption ◽  
Water Content ◽  
Wound Dressing ◽  
Chemical Properties ◽  
Physico Chemical ◽  
Time Observation ◽  
Sterilization Dose

The pre-clinical study of poly (vinyl pirrolidone) (PVP)-k- carrageenan hydrogel has been carried out. The aim of this study is to investigate the effect of hydrogel for healing burn injuried in the rats. The hydrogels were prepared by g-irradiation of aqueous solutions of 15 wt.-% PVP and 2 wt.-% k- carrageenan at a sterilization dose of 25 kGy. The physico-chemical properties of hydrogels were investigated. The results showed that the hydrogels suitable as candidate for wound dressing with gel fraction of 90 ± 5 (%), the water absorption was 4500 ± 55 (w/w), the water content was 83 ± 2 (%), tensile strength was 1,5 ± 0,1 kg/cm2 and adhesiveness was 0. The effect of the hydrogel as wound dressing was evaluated by attaching to a burn of the back skin of rats as a function of time observation. Advantages of the hydrogel were slightly faster rate of reducing radius diameter of injured burn skin, easy removal without damage to renewed skin.   Keywords: hydrogel, irradiation, copolymer, PVP, k carrageenan, diameter

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