Bausteine für die naßchemische Analyse/ Modules for the wet chemical analysis

1986 ◽  
Vol 23 (4) ◽  
pp. 219-219
Keyword(s):  
Chemical Analysis ◽  
Wet Chemical

Sector growth and symmetry of (F,OH) apatite from the Asio mine, Japan

1994 ◽  
Vol 58 (391) ◽  
pp. 307-314 ◽  
Author(s):  
Mizuhiko Akizuki ◽  
Hirotugu Nisidoh ◽  
Yasuhiro Kudoh ◽  
Tomohiro Watanabe ◽  
Kazuo Kurata
Keyword(s):  
Optical Properties ◽  
Crystal Growth ◽  
Electron Diffraction ◽  
Chemical Analysis ◽  
Growth Surface ◽  
Complete Disappearance ◽  
X Ray ◽  
Solid Crystal ◽  
Wet Chemical ◽  
Growth Features

AbstractA study of apatite crystals from the Asio mine, Japan, showed sectoral texture related to the growth of the crystal, and with optically biaxial properties within the sectors. Wet chemical analysis gave a composition Ca5(PO4)3(F0.64,OH0.38,Cl0.01)1.03 for the specimen.Additional diffraction spots were not observed in precession and oscillation X-ray photographs and electron diffraction photographs. Since the internal textures correlate with the surface growth features, it is suggested that the internal textures and the unusual optical properties were produced during nonequilibrium crystal growth. The fluorine/hydroxyl sites in hexagonal apatite are symmetrically equivalent in the solid crystal but, at a growth surface, this equivalence may be lost, resulting in a reduction of crystal symmetry. Heating of the apatite to about 850°C results in the almost complete disappearance of the optical anomalies due to disordering, which may be related to the loss of hydroxyl from the crystal.

scholarly journals How to Estimate the Binder: Aggregate Ratio From Lime-Based Historic Mortars for Restoration?

2020 ◽  
Vol 7 ◽  
Author(s):  
Alexandre Máximo Silva Loureiro ◽  
Simone Patrícia Aranha da Paz ◽  
Rômulo Simões Angélica
Keyword(s):  
Chemical Analysis ◽  
Preparation Methods ◽  
Materials Analysis ◽  
Accuracy And Precision ◽  
Adequate Accuracy ◽  
Northern Brazil ◽  
Wet Chemical ◽  
Historic Mortars ◽  
Sample Preparation Methods

One of the most important studies from historic mortars is the binder:aggregate ratio, which is usually obtained through wet chemical analysis. Instrumental techniques and benchtop equipment have become increasingly important tools in the characterization of historic materials. The analysis of such materials has become more practical, faster and more accurate, and the sample preparation methods require less and less material. Thus, this article aims to investigate the validity of the results obtained by some of the methods and techniques used in historic materials analysis and determine the possibility of estimating the binder:aggregate ratio with adequate accuracy and precision. For this purpose, historic mortars from Belém do Pará, in northern Brazil, were selected, and the following quantification techniques were employed: wet chemical analysis, XRD, DSC and XRF. The results showed that the amounts of the components in the mortars could be quantified with the use of approximately 3 g of sample, thus providing one of the main pieces of information needed for the production of a restoration mortar: the binder:aggregate ratio.

Choloalite, CuPb(TeO3)2·H2O, a new mineral

1981 ◽  
Vol 44 (333) ◽  
pp. 55-57 ◽  
Author(s):  
S. A. Williams
Keyword(s):  
Chemical Analysis ◽  
Thin Section ◽  
Type Locality ◽  
New Mineral ◽  
Wet Chemical

AbstractProbably first found in Arabia, then Moctezuma, Sonora (the type locality), finally at Tombstone, Arizona. Crystals are cubic, invariably octahedral in habit, up to 2 mm in size. Colour forest green (RHS 136A), H = 3, D = 6.4.Wet chemical analysis gave CuO 11.0%, PbO 33.0, TeO2 50.7, H2O 3.4; soluble in cold dilute acids. The strongest lines are 7.223(5), 4.170(2), 3.614(3), 3.472(4), 3.343(6), 3.036(10), 7.952(3), 2.454(5) Å. The cell indexes as cubic, a = 12.519 Å; for Z = 12, ρcalc = 6.41 g/cm3. May be anisotropic in thin section with birefringence up to 0.011; n = 2.04.

scholarly journals Mpororoite and anthoinite from the Kara mine, Tasmania

1984 ◽  
Vol 48 (348) ◽  
pp. 397-400 ◽  
Author(s):  
Satoshi Matsubara ◽  
Akira Kato ◽  
Kozo Nagashima
Keyword(s):  
Thermal Treatment ◽  
Chemical Analysis ◽  
African Continent ◽  
Essential Nature ◽  
First Occurrence ◽  
Wet Chemical

Abstract The first occurrence of mpororoite and anthoinite outside the African Continent has been found in an altered skarn from the Kara mine, Tasmania, forming a white powdery mixture of the two minerals pseudomorphing scheelite. The wet chemical analysis of the mixture shows WO3, Al2O3, and H2O to be the essential constituents, proving the non-essential nature of Fe2O3 in mpororoite; the original mpororoite contained high Fe2O3 substituting for Al2O3. The thermal treatment of the mixture at 100°C for 6 hours in air brings about the conversion of mpororoite into anthoinite, which re-hydrates into mpororoite, although the associated anthoinite does not. The source of Al is ascribed to the decomposition of aluminian andradite in the skarn.

Hole Concentration and Tc in the TI2-x-zBa2+xCa2+xCu3O10-y System

1992 ◽  
Vol 275 ◽  
Author(s):  
M. Paranthaman ◽  
M. Foldeaki ◽  
A. NaziriPour ◽  
A. M. Hermann
Keyword(s):  
Chemical Analysis ◽  
Conduction Band ◽  
Oxygen Vacancies ◽  
Single Phase ◽  
Hole Concentration ◽  
Impurity Phase ◽  
Quartz Tube ◽  
Post Annealing ◽  
Impurity Phases ◽  
Wet Chemical

ABSTRACTSingle phase Tl-2223 samples were prepared in the TI2-x-zBa2Ca2+xCu3O10-y (z represent Tl vacancies in the range 0.22 – 0.27 and y represent oxygen vacancies in the range 0.17 – 0.33) system with x between 0 and 0.4. A small impurity phase was found at x = 0.6. All samples were found to be tetragonal. The Tc varied between 112 and 118 K for the “as-synthesized” samples. After post-annealing in a sealed quartz tube under vacuum at 750*deg;C for 10 days, the Tc increased from 116 to 122 K for x = 0.3 and from 118 to 120 K for x = 0,4 samples. Although x = 0.3 sample had small impurity phases after post-annealing, a large amount of impurity phases were found for x = 0.4 sample after post-annealing. Wet chemical analysis showed that all samples were both Tl and oxygen deficient. The Tc was found to increase with increasing hole concentration. The origin of the holes for all these samples is due to Ca2+ substitution on the TI3+ sites and overlap of Tl-6s band with the conduction band of the CuO2 sheets.

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