Raman and i.r. spectra and structure of boehmite (γ-AlOOH). Evidence for the recently discarded D172h space group

Kiss, A.; Keresztury, Gábor; Farkas, László

doi:10.1016/0584-8539(80)80024-9

Cited by 185 publications

(143 citation statements)

References 10 publications

Supporting

Mentioning

125

Contrasting

Unclassified

Order By: Relevance

“…20 Beside the bands typical of boehmite all spectra contain very broad bands resulting from the vibration of adsorbed water molecules. Samples B1 and B2 also contain bands at 1560, 1420 and 1349 cm -1 , which indicate the presence of an acetate group 21 that remained from the acetic acid used in the preparation of the sample (Table 1).…”

Section: Resultsmentioning

confidence: 99%

Microstructural Analysis of Boehmite Nanoparticles Prepared by Rapid Hydrolysis of Aluminum Sec-butoxide

Štefanić¹,

Musić²

2011

Croat. Chem. Acta

View full text Add to dashboard Cite

Abstract. Microstructural properties of six samples, prepared by rapid hydrolysis of aluminum secbutoxide, were investigated at RT using field emission scanning electron microscopy (FE SEM), X-ray powder diffraction (XRD) and Fourier transform infrared (FT-IR) spectrometry. The results of structural analysis show that, regardless of a significant difference in the processing parameters (pH, temperature, time of synthesis), all products contain boehmite as the only crystal phase present. The results of FE-SEM analysis indicate a significant difference in the morphology of obtained boehmites (plates, needles, granules). The results of line-broadening analysis of powder diffraction patterns (Le Bail method -program GSAS) indicate the presence of very small anisotropic crystal domains (around 1.5 to 7 nm in the direction 010; around 3 to 16 nm in the direction perpendicular to 010). In all cases the parameters that contribute to the strain broadening of diffraction lines decrease to nearly zero, which suggests that the obtained boehmites are almost strain-free. (doi: 10.5562/cca1884)

show abstract

Section: Resultsmentioning

confidence: 99%

Microstructural Analysis of Boehmite Nanoparticles Prepared by Rapid Hydrolysis of Aluminum Sec-butoxide

Štefanić¹,

Musić²

2011

Croat. Chem. Acta

View full text Add to dashboard Cite

show abstract

“…Most likely, the surface functionalization induced a higher BA crystallinity with respect to untreated BA, or BA for silane modification was taken from another production batch. The IR spectra of BA nanopowders correspond to those reported for boehmite in the literature [28,38]. The OH stretching (* OH ) bands are at 3290 and 3091 cm -1 , while OH bending (' OH ) appears at 1151 and 1077 cm -1 , the + OH band is at 751)cm -1 , symmetrical and asymmetrical Al-O bonds stretching are at 638 and 529 cm -1 (Figure 3a).…”

Section: Mechanical Testsmentioning

confidence: 97%

Viscoelastic behaviour and fracture toughness of linear-low-density polyethylene reinforced with synthetic boehmite alumina nanoparticles

Pedrazzoli¹,

Ceccato²,

Karger‐Kocsis³

et al. 2013

Express Polym. Lett.

View full text Add to dashboard Cite

Abstract. Aim of the present study is to investigate how synthetic boehmite alumina (BA) nanoparticles modify the viscoleastic and fracture behaviour of linear low-density polyethylene. Nanocomposites containing up to 8 wt% of untreated and octyl silane-functionalized BA nanoparticles, were prepared by melt compounding and hot pressing. The BA nanoparticles were finely and unformly dispersed within the matrix according to scanning electron microscopy inspection. The results of quasi-static tensile tests indicated that nanoparticles can provide a remarkable stiffening effect at a rather low filler content. Short term creep tests showed that creep stability was significatively improved by nanofiller incorporation. Concurrently, both storage and loss moduli were enhanced in all nanocomposites, showing better result for surface treated nanoparticles. The plane-stress fracture toughness, evaluated by the essential work of fracture approach, manifested a dramatic increase (up to 64%) with the BA content, with no significant differences among the various types of BA nanoparticles.

show abstract

“…All four main forms of alumina hydroxides/oxyhydroxides have been detected, namely, bayerite {α-Al(OH)3} and gibbsite {γ-Al(OH)3}, diaspore {α-AlOOH}, and boehmite {γ-AlOOH}. A differentiation between the various forms of alumina hydrates, as well as cobalt oxides/hydroxides on the basis of the observed peak wavenumbers and relevant literature [39,67,[69][70][71][72][73][74][75][76][77], is attempted in Table 6. Three main types of Raman spectra are observed in Figure 11: (i) Spectra with predominance of bands corresponding to aluminum hydroxides/oxyhydroxides, where bands ascribed to characteristic vibrations of Co-O-Co bonds also present accountable intensity (7Co_2, 7Co_3, 20Co_1, 20Co_3).…”

Section: Surface Film Identificationmentioning

confidence: 99%

Al-Co Alloys Prepared by Vacuum Arc Melting: Correlating Microstructure Evolution and Aqueous Corrosion Behavior with Co Content

Lekatou

Sfikas

Petsa

et al. 2016

Metals

View full text Add to dashboard Cite

Hypereutectic Al-Co alloys of various Co contents (7-20 weight % (wt.%) Co) were prepared by vacuum arc melting, aiming at investigating the influence of the cobalt content on the microstructure and corrosion behavior. Quite uniform and directional microstructures were attained. The obtained microstructures depended on the Co content, ranging from fully eutectic growth (7 wt.% and 10 wt.% Co) to coarse primary Al 9 Co 2 predominance (20 wt.% Co). Co dissolution in Al far exceeded the negligible equilibrium solubility of Co in Al; however, it was hardly uniform. By increasing the cobalt content, the fraction and coarseness of Al 9 Co 2 , the content of Co dissolved in the Al matrix, and the hardness and porosity of the alloy increased. All alloys exhibited similar corrosion behavior in 3.5 wt.% NaCl with high resistance to localized corrosion. Al-7 wt.% Co showed slightly superior corrosion resistance than the other compositions in terms of relatively low corrosion rate, relatively low passivation current density and scarcity of stress corrosion cracking indications. All Al-Co compositions demonstrated substantially higher resistance to localized corrosion than commercially pure Al produced by casting, cold rolling and arc melting. A corrosion mechanism was formulated. Surface films were identified.

show abstract

Raman and i.r. spectra and structure of boehmite (γ-AlOOH). Evidence for the recently discarded D172h space group

Cited by 185 publications

References 10 publications

Microstructural Analysis of Boehmite Nanoparticles Prepared by Rapid Hydrolysis of Aluminum Sec-butoxide

Microstructural Analysis of Boehmite Nanoparticles Prepared by Rapid Hydrolysis of Aluminum Sec-butoxide

Viscoelastic behaviour and fracture toughness of linear-low-density polyethylene reinforced with synthetic boehmite alumina nanoparticles

Al-Co Alloys Prepared by Vacuum Arc Melting: Correlating Microstructure Evolution and Aqueous Corrosion Behavior with Co Content

Contact Info

Product

Resources

About