Tritium exchange studies on metal oxide colloidal dispersions

1977 ◽  
Vol 30 (8) ◽  
pp. 1655 ◽  
Author(s):  
DE Yates ◽  
F Grieser ◽  
R Cooper ◽  
TW Healy
Keyword(s):  
Crystal Structure ◽  
Heat Treatment ◽  
Iron Oxide ◽  
Metal Oxide ◽  
Iron Oxides ◽  
Colloidal Dispersions ◽  
Water Interface ◽  
Amorphous Iron ◽  
Tio2 Rutile ◽  
Exchange Technique

The tritium exchange technique has been used to detemine the maximum number of surface protons at the oxide-water interface for oxide colloids including silicas, TiO2 (rutile) and the iron oxides goethite, hematite and amorphous iron oxide. The effects of heat treatment, crystal structure and exchange conditions are considered and tritium exchange values for the number of surface protons are compared with values calculated from crystal structures.

scholarly journals Discovery of Fe7O9: a new iron oxide with a complex monoclinic structure

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Ryosuke Sinmyo ◽  
Elena Bykova ◽  
Sergey V. Ovsyannikov ◽  
Catherine McCammon ◽  
Ilya Kupenko ◽  
...  
Keyword(s):  
Applied Sciences ◽  
Crystal Structure ◽  
Iron Oxide ◽  
Iron Oxides ◽  
Industrial Applications ◽  
Ambient Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Insight Into

Abstract Iron oxides are fundamentally important compounds for basic and applied sciences as well as in numerous industrial applications. In this work we report the synthesis and investigation of a new binary iron oxide with the hitherto unknown stoichiometry of Fe7O9. This new oxide was synthesized at high-pressure high-temperature (HP-HT) conditions, and its black single crystals were successfully recovered at ambient conditions. By means of single crystal X-ray diffraction we determined that Fe7O9 adopts a monoclinic C2/m lattice with the most distorted crystal structure among the binary iron oxides known to date. The synthesis of Fe7O9 opens a new portal to exotic iron-rich (M,Fe)7O9 oxides with unusual stoichiometry and distorted crystal structures. Moreover, the crystal structure and phase relations of such new iron oxide groups may provide new insight into the cycling of volatiles in the Earth’s interior.

Photodegradation, interaction with iron oxides and bioavailability of dissolved organic matter from forested floodplain sources

2008 ◽  
Vol 59 (9) ◽  
pp. 780 ◽  
Author(s):  
Julia A. Howitt ◽  
Darren S. Baldwin ◽  
Gavin N. Rees ◽  
Barry T. Hart
Keyword(s):  
Organic Matter ◽  
Iron Oxide ◽  
Dissolved Organic Matter ◽  
Iron Oxides ◽  
Photochemical Reactions ◽  
Oxbow Lake ◽  
Photochemical Degradation ◽  
Fluorescence Excitation ◽  
Amorphous Iron ◽  
Leaf Leachate

Photochemical degradation of dissolved organic matter (DOM) can influence food webs by altering the availability of carbon to microbial communities, and may be particularly important following periods of high DOM input (e.g. flooding of forested floodplains). Iron oxides can facilitate these reactions, but their influence on subsequent organic products is poorly understood. Degradation experiments with billabong (= oxbow lake) water and river red gum (Eucalyptus camaldulensis) leaf leachate were conducted to assess the importance of these reactions in floodplain systems. Photochemical degradation of DOM in sunlight-irradiated quartz tubes (with and without amorphous iron oxide) was studied using gas chromatography and UV-visible spectroscopy. Photochemical reactions generated gaseous products and small organic acids. Bioavailability of billabong DOM increased following irradiation, whereas that of leaf leachate was not significantly altered. Fluorescence excitation-emission spectra suggested that the humic component of billabong organic matter was particularly susceptible to degradation, and the source of DOM influenced the changes observed. The addition of amorphous iron oxide increased rates of photochemical degradation of leachate and billabong DOM. The importance of photochemical reactions to aquatic systems will depend on the source of the DOM and its starting bioavailability, whereas inputs of freshly formed iron oxides will accelerate the processes.

Preparation and Characterization of CuO/ZnO/PVDF/PAN Nanofiber Composites by Bubble-electrospinning

2020 ◽  
Vol 13 (3) ◽  
pp. 196-201 ◽  
Author(s):  
Fang Wei ◽  
Liu Ling ◽  
Xu Lan
Keyword(s):  
Crystal Structure ◽  
Heat Treatment ◽  
Metal Oxide ◽  
Hydrothermal Method ◽  
Mass Production ◽  
Heat Treatment Temperature ◽  
Treatment Temperature ◽  
Zno Nanocrystals ◽  
Cuo Nanocrystals ◽  
Nanofiber Membranes

Background: Nanocomposites loaded with metal oxides, such as CuO and ZnO, have excellent optical, electrical, mechanical and chemical properties, which result in their great potential applications in optoelectronic devices, sensors, photocatalysts and other fields. Especially, electrospun metal- oxide-loaded nanofibers have attracted much attention in many fields. However, the single-needle Electrospinning (ES) inhibits the industrial application of these electrospun nanofiber composites. Bubble-Electrospinning (BE) is an effective free surface ES for mass production of nanofiber membranes loaded with metal oxide. Few relevant patents to the topic have been reviewed and introduced. Methods: The BE was used to prepare mass production of Cu(Ac)2 /Zn(Ac)2/ PVDF/ PAN Composite Nanofiber Membranes (CNFMs). Then PVDF/PAN CNFMs containing CuO and ZnO nanocrystals were obtained by heat-treatment. Finally, CuO nanosheets and ZnO nanorods were successfully grown on the surface of PVDF/PAN CNFMs using hydrothermal method. In addition, the morphology and crystal structure of CNFMs were investigated by scanning electron microscopy (SEM) and X-Ray Powder Diffractometer (XRD). Results: The morphology and crystal structure of the samples were characterized by SEM and XRD. The results showed the heat treatment temperature of 150oC and the hydrothermal temperature of 150oC were the optimal process parameters for the fabrication of PVDF/PAN CNFMs loaded with CuO and ZnO nanocrystals, and a higher heat treatment temperature results in higher crystallinity of ZnO and CuO. Conclusion: CuO/ZnO/PVDF/PAN CNFMs were successfully prepared by a combination of BE, heattreatment and hydrothermal method. The ZnO/CuO beads obtained by heat treatment is the key point of growing ZnO/CuO nanocrystals, and the growth temperature has great effect on the morphology of ZnO/CuO nanocrystals.

THE EFFECTS OF ORGANIC MATTER, IRON OXIDES AND MOISTURE ON THE COLOR OF TWO AGRICULTURAL SOILS OF QUEBEC

1979 ◽  
Vol 59 (2) ◽  
pp. 191-202 ◽  
Author(s):  
S. CHOMCHAN ◽  
R. G. LEGER ◽  
G. J. F. MILLETTE
Keyword(s):  
Organic Matter ◽  
Iron Oxide ◽  
Iron Oxides ◽  
Agricultural Soils ◽  
Area Ratio ◽  
Oxide Coatings ◽  
Soil Color ◽  
Amorphous Iron ◽  
Reflectance Curve ◽  
Iron Oxide Coatings

A new spectrophotometric interpretation of the influence of organic matter, iron oxides and moisture on the soil color of the Ste-Sophie sand and the Ste-Rosalie clay is reported. The method is based on calculation of the area ratio of the reflected (area under the reflectance curve) against the absorbed (area over the reflectance curve). The higher the ratio the lighter is the soil. After treatment to remove organic matter and iron oxide coatings, both soils presented colors significantly lighter than those observed in untreated soils. Organic matter and amorphous iron oxide contributed for 78% and 64% of the color in the Ste-Sophie sand and in the Ste-Rosalie clay, respectively. Moisture tends to mask the effects of organic matter and iron oxides on soil color. Air-dried soils when compared to moistened soils were lighter in color.

Selective extraction of amorphous iron oxides by EDTA from selected silicates and mixtures of amorphous and crystallline iron oxides

Clay Minerals ◽  
1982 ◽  
Vol 17 (3) ◽  
pp. 365-368 ◽  
Author(s):  
O.K. Borggaard
Keyword(s):  
Iron Oxide ◽  
Iron Oxides ◽  
Ammonium Oxalate ◽  
Reference Method ◽  
Selective Extraction ◽  
Synthetic Mixture ◽  
Amorphous Iron ◽  
Oxalate Solution

Amorphous iron oxides in soil are often extracted by an ammonium oxalate solution (Schwertmann, 1964). This treatment may, however, also dissolve crystalline iron oxides and iron silicates (McKeague & Day, 1966; Baril & Bitton, 1969; McKeague et al., 1971; Arshad et al., 1972; Pawluk, 1972; Schwertmann, 1973; Taylor & Schwertmann, 1974; Borggaard, 1976).It has been shown that EDTA can selectively extract amorphous iron oxides from soils (Borggaard, 1979, 1981) and a synthetic mixture of amorphous iron oxide, goethite, and hematite (Borggaard, 1976). As pointed out previously (Borggaard, 1979), the EDTA method should also be tested on selected minerals to decide if it can serve as a reference method against which other less time-consuming methods may be tested.

scholarly journals INVESTIGATION OF SURFACES OF NOVEL IRON OXIDES WITH GRAIN AND GRAIN BOUNDARY

2018 ◽  
Vol 56 (1A) ◽  
pp. 226
Author(s):  
Nguyet Viet Long
Keyword(s):  
Heat Treatment ◽  
Iron Oxide ◽  
Grain Boundary ◽  
Iron Oxides ◽  
Particle System ◽  
Oxide Particle ◽  
Oxide System ◽  
Iron Oxide Particle ◽  
Iron Oxide Particles ◽  
Oxide Particles

Hierarchical nano/microscale α-Fe2O3 iron oxide particle system was prepared by an improved and modified polyol method with the use of NaBH4 agent with high heat treatment at 900 °C in air. Here, α-Fe2O3 iron oxide particles with different shapes were analyzed. The morphologies of the surfaces of α-Fe2O3 iron oxide particles show the oxide structures with the different nano/microscale ranges of grain sizes. In this research, we have found that grain and grain boundary growth limits can be determined in α-Fe2O3 iron oxide structure. This leads to the possibility of producing new iron oxide structures with distribution of desirable size grain and grain boundary. With α-Fe2O3 structure obtained, the magnetic properties of the α-Fe2O3 iron oxide system are different from those of previously reported studies. in national and international studies.Keywords: Iron iron oxides, α-Fe2O3, chemical polyol methods, heat treatment.

Sonochemical Synthesis of Functionalized Amorphous Iron Oxide Nanoparticles

Langmuir ◽  
2001 ◽  
Vol 17 (16) ◽  
pp. 5093-5097 ◽  
Author(s):  
Kurikka V. P. M. Shafi ◽  
Abraham Ulman ◽  
Xingzhong Yan ◽  
Nan-Loh Yang ◽  
Claude Estournès ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Sonochemical Synthesis ◽  
Amorphous Iron

scholarly journals Effects of Sulfate Ion on Crystal Structure and Activity for Methane Oxidation of Iron Oxide Prepared from Goethite.

2002 ◽  
pp. 11-18 ◽  
Author(s):  
Masanao ORIHARA ◽  
Suminori TANAKA ◽  
Sigeo KAWAKAMI ◽  
Kazunori NAKAGAWA ◽  
Masahiro KATO ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Iron Oxide ◽  
Methane Oxidation ◽  
Sulfate Ion ◽  
Structure And Activity

Structural regulation of iron oxide supported on a metal oxide by organic compounds

1988 ◽  
pp. 1540 ◽  
Author(s):  
Fujio Mizukami ◽  
Yasuhiro Kobayashi ◽  
Shu-ichi Niwa ◽  
Makoto Toba ◽  
Kazuo Shimizu
Keyword(s):  
Iron Oxide ◽  
Metal Oxide ◽  
Organic Compounds ◽  
Structural Regulation

Waste Plastic Sachet as Alternative Anti-Corrosion Filler for Iron Oxide in Resin Coatings

2021 ◽  
Vol 877 ◽  
pp. 9-14
Author(s):  
Francis Darwin T. Eugenio ◽  
Bryan B. Pajarito
Keyword(s):  
Corrosion Resistance ◽  
Iron Oxide ◽  
Film Thickness ◽  
Iron Oxides ◽  
Water Resistance ◽  
Inorganic Compounds ◽  
Environmental Issues ◽  
Metal Coatings ◽  
Waste Plastic ◽  
Coating Mixture

Iron oxides and similar inorganic compounds have served as anti-corrosion fillers for metal coatings. Environmental issues related to the mining of metallic fillers have stimulated interest in alternative fillers such as organic fillers. This paper explores the use of comminuted waste plastic sachets (WPS) as an anti-corrosion filler to resin-based metal coating. Mixture design of experiment was used to study the effect of iron oxide-WPS blends on the film thickness, viscosity, corrosion behavior, and water resistance of the coating. Results show that the film thickness was affected by the presence of iron oxide while the viscosity of the coating was affected by high loads of WPS. Among all coatings, the blend containing 25% iron oxide and 75% WPS produced the highest corrosion resistance. In conclusion, comminuted WPS provided additional corrosion resistance and could serve as an alternative anti-corrosion filler.

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