Effects of water content on electrochemical capacitive behavior of nanostructured Cu3(BTC)2 MOF prepared in aqueous solution

2021 ◽  
Vol 368 ◽  
pp. 137616
Author(s):  
Eshagh Irandoost ◽  
Hossein Farsi ◽  
Alireza Farrokhi
Keyword(s):  
Aqueous Solution ◽  
Water Content ◽  
Capacitive Behavior

Cerium Tetrafluoride. I. Preparation and reactions

1965 ◽  
Vol 18 (7) ◽  
pp. 959 ◽  
Author(s):  
WJ Asker ◽  
AW Wylie
Keyword(s):  
Aqueous Solution ◽  
Water Content ◽  
Water Vapour ◽  
Hydrogen Fluoride ◽  
Low Temperatures ◽  
Cerium Dioxide ◽  
Lattice Parameters ◽  
Refractive Indices ◽  
Dissociation Pressure ◽  
Cerium Trifluoride

Pure anhydrous cerium tetrafluoride is best prepared by fluorinating cerium dioxide at 350-500�. A monohydrate can be obtained from aqueous solution in a variety of ways, but it cannot be dehydrated without decomposition. It loses water "zeolitically" in vacuum, showing relatively small changes in lattice parameters for loss of 70% of its water content. Thereafter the lattice collapses, forming well-crystallized cerium trifluoride and poorly crystallized "anhydrous" cerium tetrafluoride. The refractive indices of anhydrous monoclinic cerium tetrafluoride have been measured and its fluorine dissociation pressure at 500� shown to be less than 0.5 mm. At higher temperatures the tetrafluoride sublimes incongruently, and at 835-841� it melts with extensive decomposition into a fluorine-poor liquid and a fluorine-rich vapour. Cerium tetrafluoride is easily reduced to the trifluoride by ammonia and by water vapour at low temperatures. At higher temperatures it is quantitatively converted by water vapour to cerium dioxide and hydrogen fluoride. When heated with cerium dioxide it is reduced to the trifluoride with liberation of oxygen.

Controllable Synthesis of Spheroid Hydroxyapatite Nanoparticles by Rverse Microemulsion Method

2012 ◽  
Vol 602-604 ◽  
pp. 227-230
Author(s):  
Tao Fan ◽  
Yan Rong Sun ◽  
Li Guo Ma
Keyword(s):  
Aqueous Solution ◽  
Water Content ◽  
Ph Value ◽  
Particle Diameter ◽  
Diameter Distribution ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Homogeneous Good

Spheroid hydroxyapatite nanoparticles were successfully prepared by titrating Ca(NO3)2•4H2O and (NH4)2HPO4 aqueous solution in the reverse microemulsion, which consists of mixed OP-10(surfactant), cyclohexane(oil phase), and isobutanol (cosurfactant).The structure and morphology of the prepared powders were characterized by means of X-ray diffraction (XRD) and transmission electron microscope (TEM). The optimum composition was investigated via the analysis of the aqueous solution conductivity, and the mechanism of aqueous reaction. The effect of the pH value and the amount of surfactant on the particle size were studied. The results indicate that the best conditions are which the concentration of OP-10 and isobutanol both are 0.2 M, when the water content is between 130 ml-250 ml，it results in pure nano-hydroxyapatite spheroid-like powders, and the water content is about 200 ml, whose diameters are 50 nm-80 nm, and good particle diameter distribution, the particle microstructure is homogeneous, good crystal structure and higher crystallinity.

Effect of Water on the IR Properties of Mg2+ Intercalated Electrochromic Nb2O5 Thin Films

2006 ◽  
Vol 972 ◽  
Author(s):  
Gargi Agarwal ◽  
G B Reddy
Keyword(s):  
Thin Films ◽  
Aqueous Solution ◽  
Water Content ◽  
Current Density ◽  
Sol Gel ◽  
Constant Current ◽  
Cyclic Stability ◽  
Constant Current Density ◽  
Effect Of Water ◽  
Ftir Studies

AbstractSol-gel derived Nb2O5 thin films were intercalated with Mg2+,using the non-aqueous solution of Mg(ClO4)2 in propylene carbonate (pc) as the electrolyte. 2% and 4% ( volume %) water was added to the electrolyte to study the effect of water on the electrochromic properties of Nb2O5. This paper presents the changes in optical and structural properties of the intercalated films with and without water in the electrolyte. The ratio (x) of the Mg2+ and Nb atoms has been controlled by optimizing the intercalation duration under a constant current density. The fall in transmittance on intercalation (for x= 0.8) increased by 15% with 4% water in the electrolyte, compared to the film intercalated without water. FTIR studies show that water is incorporated in the films on intercalation and small quantities of Mg(OH)2 and Nb-OH are formed along with Mg-O-Nb bonds. The presence of water in electrolyte decreases water content in the films and enhances the formation of Mg(OH)2, Mg-O-Nb and Nb-OH bonds. The recovery of Mg2+ on deintercalation is slightly reduced in presence of water in the electrolyte. The cyclic stability of the films intercalated without water is more than that of the films intercalated in presence of water.

Application of an N-Methylol Crosslinking Agent to Cotton from an Emulsion System

1977 ◽  
Vol 47 (5) ◽  
pp. 328-332 ◽  
Author(s):  
S. M. Betrabet ◽  
E. H. Daruwalla ◽  
S. M. Doshi
Keyword(s):  
Mechanical Properties ◽  
Aqueous Solution ◽  
Water Content ◽  
Crosslinking Agent ◽  
Cross Linking ◽  
Emulsion System ◽  
Water Emulsion ◽  
Preferential Uptake ◽  
Different Levels

Application of DMDHEU from a kerosene-water emulsion system at different levels of water content in the system has been examined with respect to the extent of crosslinking and mechanical properties of the finished fabrics. As the water content of the treating bath is decreased, both wet and dry wrinkle-recovery angles, bound nitrogen, and bound HCHO in the crosslinked fabric increase, but there is no improvement noticed in the wrinkle-recovery/mechanical properties relationship. The increase in the extent of cross linking during application from the emulsion system appears to be due to preferential uptake of the aqueous solution containing the crosslinking agent from the emulsion system.

Osmolality and Unfrozen Water Content of Aqueous Solution of Dimethyl Sulfoxide

2011 ◽  
Vol 56 (7) ◽  
pp. 3175-3182 ◽  
Author(s):  
Lindong Weng ◽  
Weizhong Li ◽  
Jianguo Zuo ◽  
Cong Chen
Keyword(s):  
Aqueous Solution ◽  
Dimethyl Sulfoxide ◽  
Water Content ◽  
Unfrozen Water ◽  
Unfrozen Water Content

Monitoring Organic Thin Film Growth In Aqueous Solution In-situ With A Combined Quartz Crystal Microbalance and Ellipsometry

2008 ◽  
Vol 1146 ◽  
Author(s):  
Amitabha Sarkar ◽  
Tapani Viitala ◽  
Tino Hofmann ◽  
Tom E. Tiwald ◽  
John A. Woollam ◽  
...  
Keyword(s):  
Thin Film ◽  
Aqueous Solution ◽  
Water Content ◽  
Quartz Crystal Microbalance ◽  
Quartz Crystal ◽  
Film Growth ◽  
High Water Content ◽  
Organic Thin Film ◽  
Polymer Thin Film

AbstractThe change of the visible light ellipsometric parameters and mechanical harmonic frequencies of a hydrophobic gold surface attached to a quartz crystal are measured in aqueous solution during deposition of synperonic polymer thin film. The ellipsometry data reveal the amount of polymer mass attached to the surface, while the mechanical resonance shifts are caused by the total mass attached to the surface. Analysis of the combined ellipsometry and quartz crystal microbalance data reveal that the polymer thin film has a high water content, and we determine in-situ, for the first time, the porosity, or the water content, of a polymer thin film in aqueous solution.

Preparation Process of Glass Membrane Using Non-Solvent Induced Phase Separation

2016 ◽  
Vol 680 ◽  
pp. 297-300 ◽  
Author(s):  
Ya Bin Zhang ◽  
Guang You Pan ◽  
Ya Ping Zhao ◽  
Jia Wei Xu ◽  
Hai Tao Feng
Keyword(s):  
Aqueous Solution ◽  
Phase Separation ◽  
Water Content ◽  
Calcination Temperature ◽  
Glass Powder ◽  
Bath Temperature ◽  
Coagulation Bath ◽  
Preparation Process ◽  
Glass Membrane ◽  
Coagulation Bath Temperature

The glass membrane was fabricated by non-solvent-induced phase separation (NIPS) and sintering technique. The preparation process was studied. PVDF was dissolved into DMAc completed. Subsequently, the used glass powder was added into above aqueous solution. The obtained slurry was tape-casted and a green membrane formed. The green membrane was immersed into coagulation bath. The exchange between DMAc and water in coagulation bath took place, and PVDF-containing glass membrane was obtained. The membrane was calcined at different temperature, and the glass membrane was prepared. In order to evaluate the porosity of membrane, many factors including water content in coagulation bath, PVDF content in slurry, coagulation bath temperature and calcination temperature were studied. The viscosity of slurry and shrinkage of membrane after calcination were also studied.

Structures Formed by Cryoprotective Agents Used in Freezc-Etching

1971 ◽  
Vol 29 ◽  
pp. 448-449
Author(s):  
G. G. Cocks ◽  
C. E. Cluthe
Keyword(s):  
Aqueous Solution ◽  
Polyethylene Oxide ◽  
Liquid Nitrogen Temperature ◽  
Ice Crystals ◽  
Etching Technique ◽  
Structural Constituent ◽  
Cryoprotective Agents ◽  
Quick Freezing ◽  
Freeze Etching ◽  
Fractured Surface

The freeze etching technique is potentially useful for examining dilute solutions or suspensions of macromolecular materials. Quick freezing of aqueous solutions in Freon or propane at or near liquid nitrogen temperature produces relatively large ice crystals and these crystals may damage the structures to be examined. Cryoprotective agents may reduce damage to the specimem, hut their use often results in the formation of a different set of specimem artifacts.In a study of the structure of polyethylene oxide gels glycerol and sucrose were used as cryoprotective agents. The experiments reported here show some of the structures which can appear when these cryoprotective agents are used.Figure 1 shows a fractured surface of a frozen 25% aqueous solution of sucrose. The branches of dendritic ice crystals surrounded hy ice-sucrose eutectic can be seen. When this fractured surface is etched the ice in the dendrites sublimes giving the type of structure shown in Figure 2. The ice-sucrose eutectic etches much more slowly. It is the smooth continuous structural constituent surrounding the branches of the dendrites.

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