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X-ray diffraction powder pattern for

The x-ray diffraction powder pattern for Mg2NiH4 was indexed on the basis of a tetragonal crystal system with unit cell dimensions of a = 6.464 A and c = 7.033 A. The measured density was 2.57 g/cm3, compatible with four formula units of Mg2NiH4 per unit cell. [Pg.378]

Figure 2.2 Effect of the R = [HF]/[Al] molar ratio on the X-ray diffraction powder pattern. For each X-ray diagram, the R molar ratio is noticed as well as the stabilized phase. Syntheses were conducted at T = 160°C, t— 2h using Al(N03)3.9 Fl20 and water/isopropanol as solvents... Figure 2.2 Effect of the R = [HF]/[Al] molar ratio on the X-ray diffraction powder pattern. For each X-ray diagram, the R molar ratio is noticed as well as the stabilized phase. Syntheses were conducted at T = 160°C, t— 2h using Al(N03)3.9 Fl20 and water/isopropanol as solvents...
X-ray diffraction powder patterns were recorded on a CGR Theta 60 instrument, using monochromated CuKa radiation. The adsorption capacities for several adsorbates were measured at room temperature by gravimetry, using a Cahn RH microbalance as proposed by Vaughan and Lussier (3 ). The samples were first treated in air for 5 hours at 480°C. The experiment was performed by passing, over the sample, a stream of nitrogen saturated by the vapor pressure of the sorbate at room temperature, the relative pressure P/Po was then equal to 1. [Pg.240]

X-Ray Diffraction Data. The X-ray diffraction powder patterns of the cancrinites, referred to in the synthesis section, have been indexed in accordance with the space group P63 as found by Jarchow (16). Table II reports the cell parameters of the three synthetic cancrinite samples and of a natural sample (16) for comparison. Chemical Analysis. Data for the three cancrinite samples on anhydrous basis are shown in Table III. Values of water content are reported in the next section. [Pg.203]

The X-ray diffraction (XRD) patterns for the samples were recorded on a Rigaku D/max-IlB Powder X-ray Diffractometer. [Pg.92]

Ammonium cyanate is a white solid, which rearranges to urea upon prolonged storage or heating. It is extremely soluble in water, slightly soluble in acetonitrile, ethanol, and chloroform, and insoluble in benzene and diethyl ether. The infrared spectrum and x-ray diffraction powder pattern are most useful for determining the absence of urea in the final product. Nujol mulls of pure ammonium cyanate exhibit absorptions at 3160 (s), 2190 (s), 1334 (m), 1243 (m), and 640 (m) cm-i and are free of any infrared-active bands in the regions characteristic of urea, that is, 3456 and 1683 cm-i. [Pg.136]

X-Ray diffraction powder patterns were developed by using a chromium source and a Phillips Debye-Sherrer camera. Due to their small size, the samples from the back of the halberd were irradiated for 12.5 h, and the green pseudomorph sample for 12.3 h. The black pseudomorph sample, larger, was irradiated for only 5 h. The exposed film was measured in accordance with standard procedures (8) and the resulting diffraction spacing values were compared to standard values of known materials (9). [Pg.407]

The polymer is a clear, colorless and brittle solid with an elemental analysis for C7HgSi of C = 65.8% (69.9%), H = 6.73% (6.71%) (figures in parentheses are calculated values). The X-ray diffraction powder patterns show that this polymer is amorphous. The IR spectrum shows vibrational peaks for Si-phenyl at 1433 and llOOcm (s). Si-methyl at 1250 cm (vs) and Si—Si at 462 cm (s). The IR spectrum is similar to that reported by Trujillo [8]. The polymer has a monomodal molecular weight, Mw =... [Pg.614]

The films were deposited onto NaCl or KBr discs to facilitate examination by infrared transmission. Substrates of platinum, aluminum, ALOn, and fused SiO approximately one cm. in diameter were prepared for the rate studies. The index of refraction and isotropic character of film specimens obtained from the substrates and/or gas inlet tube were determined with a petrographic microscope. Debye-Scherrer x-ray diffraction powder patterns were made to establish whether the films were amorphous or crystalline. [Pg.251]

Initially, 0.5 g (1 mmole) Rb2[Pt(CN)4] 1.5H204 is added to 15 mL H20 with heating (approx. 70°) and stirring. Approximately 1 mL liquefied chlorine gas, cooled in an acetone/dry ice bath, is added cautiously. ( Caution. Chlorine gas is a hazardous material. Handle with care ) The mixture is then stirred for 20 minutes to drive off the excess chlorine, and then an additional 2.5 g (5 mmole) Rb2[Pt(CN)4] 1.5H20 is added. The solution is allowed to stir for another 15 minutes and then evaporated by boiling to 10 mL and finally cooled in an ice bath. The resulting crystals are isolated. An X-ray diffraction powder pattern demonstrates that the crystals are monoclinic Rb 175 [Pt(CN)4] 1.5H20. [Pg.145]

M0R] Morris, M. C., Standard X-ray diffraction powder patterns. Section 18 - Data for 58 substances. Final report. National Bureau of Standards Monograph, p. 79, NBS, Washington, D.C., (1981). Cited on page 144. [Pg.465]

FIGURE 3.50 Change in x-ray diffraction (XRD) pattern with heat treatment of commercial Ti 02 i powder (Ebonex) with or without poly(vinyl alcohol) (PVA) (refer to Table 3.7). X-ray diffraction (XRD) pattern for ST-01 is also shown for comparison. [Pg.237]

Characterization measurements of pillared clays consist, usually, of nitrogen BET specific surface area, S, and X-ray diffraction powder patterns, as well as of the adsorption capacities for a series of adsorbates, although a proper differentiation is not usual between the eunount taken up into the Interlamellar spacing and that on the external surface, as multilayer and condensed in mesopores. Upon calcination, there is a contraction of the d(OOl) spacing. Diverse trivalent lanthanide cations are added by ion exchange in order to improve the thermal stability of the pillared clays. From measurements, the existence of a positive effect by the lanthanides has been suggested (2,3). [Pg.607]

Powder X-ray diffraction (XRD) patterns of the catalysts were obtained using a Philips APD X-ray diffraction spectrometer equipped with a Cu anode and Ni filter operated at 40 kV and 20 mA (CuKa = 0.15418 nm). Iron phases were identified by comparing diffraction patterns of the catalyst samples with those in the standard powder XRD file compiled by the Joint Committee on Powder Diffraction Standards published by the International Center for Diffraction Data. [Pg.195]

The Mo-substituted ZrW20g was obtained by a precursor route at low temperature [13, 14]. The powder X-ray diffraction (XRD) patterns of ZrW2.gMOgOg (x=0.4, 0.6) showed a-ZrW20g form after calcination at 873 K. However, for x=0.7-1.5, the powder XRD patterns of ZrW2 gMOgOg only showed the P- ZrWgOg form at temperature as low as 723 K [13, 14]. [Pg.131]

X-ray Diffraction of Pure MoFe, Low Temperature Form. X-ray diffraction powder photographs taken below — 10°C. are indexable on the basis of an orthorhombic unit cell. Lattice constants from a pattern obtained at —20°C. are a = 9.65 zb 0.02A., b = 8.68 =b 0.03A., and c = 5.05 dz 0.02A. An orthorhombic MoFe diffraction pattern was calculated using the atomic coordinates derived by Hoard and Stroupe (8) for UFe. [Pg.314]


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Diffraction patterns

For X-rays

Powder diffraction

Ray Diffraction Patterns

X pattern

X powder

X powder pattern

X-Ray powder diffraction, for

X-ray diffraction patterns, for

X-ray pattern

X-ray powder

X-ray powder diffraction

X-ray powder diffraction patterns

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