Characterization by XRD

The FWHM of the XRD peak on GaN (1012)plane is an indicator of the total density of TDs. The XRD(1012) data of all samples are listed in Table 6.3. The (1012) FWHMs of GaN layers grown on porous TiN are smaller than those of their reference samples, indicating the effectiveness of porous TiN on defect reduction. 

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Uosaki K, Shen Y and Kondo T 1995 Preparation of a highiy ordered Au(111) phase on a poiycrystaiiine goid substrate by vacuum deposition and its characterization by XRD, GiSXRD, STM/AFM and eiectrochemicai measurements J.Phys. Chem. 99 14 117-14 122... 

The conventional sol-gel method was employed for the preparation of Ti02 and A1 (5.0- and 10.0-mol-%)-TiO2 catalysts. And these catalysts were characterized by XRD[model PW 1830 from Philips], SEM[model JEOL-JSM35CF], XPS[ESCA 2000], and TPD analyses for the elucidation of siuface phenomena. 

To better understand the differences in their catalytic behavior, the catalysts were characterized by XRD and UV-vis DRS. Unfortunately, except for the peak at 77.6° 26 (311 diffraction), the other Au diffraction peaks overlapped with those of y-Al203. The size of the coherent domains of Au, listed in Table I, were estimated using the width of this diffraction peak and the Debye-Sherrer equation. They showed that catalysts of both groups A and C had small coherent domains, whereas those of group B had large domains. 

Several undecagold clusters have been characterized by XRD, such as [AunI3(PR3)7] (PR3 = PPh3, C6H4F-4, C6Fl4Cl-4),3233,3246,3247 [Aun(SCN)3(dppm)5] 3248 [AunI(CN-... 

Platinum complexes [PtCl2(diphosphine)] and [PtCl(SnCl3)(diphosphine)] of the ferrocenyl diphosphine ligands (35a), (35b), and (36) have been synthesized. Complexes [PtCl2(35)] and [PtCl2(36)] have been structurally characterized by XRD. Both the preformed and the in situ catalysts have been used in the hydroformylation of styrene.112... 

A new composite containing montmorillonite and zeolite Beta was prepared and characterized by XRD, N2 adsorption-desorption, FT-IR, SEM and catalytic testing. It indicates that nano-zeolite Beta grows on montmorillonite, and high diffusion is obtained, due to the abundance of interspace formed in composite. 

Beta/montmorillonite composite was prepared under dynamic hydrothermal conditions. Firstly, montmorillonite calcined at 800 °C were added to a diluted solution of sodium hydroxide, potassium chloride and TEAOH in distilled water and the resulting mixture was vigorously stirred for 1 h secondly, silica sol was added into the above uniform mixture to allow at least 3 h stirring finally, the gel was moved into stainless steel autoclaves (1L) and heated at 413 K for 48 h. The samples were characterized by XRD, N2 adsorption-desorption, FT-IR and SEM-EDS. The catalytic assessment experiments were carried out in a flowing-type apparatus designed for continuous operation. 

Solids were characterized by XRD, N2.BET surface area, and FT-IR. The antacid capacity of the synthesized zeolites was evaluated using the methodology reported by Rivera et al. [7] and Linares et al. [6]. The pepsin enzymatic activity was determined by the reaction between a specific mass of the solid and a denatured haemoglobin solution [8]. 

Hybrid catalysts consisting of a zeolite (ZSM-5 or Beta) and bentonite as a binder were prepared and characterized by XRD, pyridine FTIR and nitrogen adsorption. The hybrid catalysts exhibited similar properties as the combined starting materials. Catalytic pyrolysis over pure ZSM-5 and Beta as well as hybrid catalysts has been successfully carried out in a dual-fluidized bed reactor. De-oxygenation of the produced bio-oil over the different zeolitic materials was increased compared to non-catalytic pyrolysis over quartz sand. 

Fe3+, La3+ and Ce3+ ion-exchanged MAPO-36 was prepared by wet ion-exchange method. The materials were characterized by XRD, TGA and TPD (ammonia). Lewis acid metal ions are suggested to remain as charge compensating MO+ species after calcination in ion-exchanged MAPO-36. Beckmann rearrangement of cyclohexanone oxime was studied over these catalysts in the vapour phase. 

The used catalysts (after separation) and the starting materials were characterized by XRD. The 10 % Cr3+ Ni2+ or Cu2+ content does not alter the structure of the HT, however high structural changes could be observed during the reaction. 

Nanosized anatase (< 10 nm) and brookite ( 70 run) particles have been successfully synthesized via sonication and hydrothermal methods. Figure 5.1 shows the powder XRD patterns of as-synthesized anatase and brookite nanoparticles. The particle sizes were characterized by XRD and scanning electron microscopy (SEM) (Fig. 5.2). 

Each individual composite disk specimen was immersed in a 100 mL NaCl solution [HEPES-buffered (pH = 7.4), 240 mOsm/kg, 37°C, continuous magnetic stirring] for up to 264 h. Aliquots were taken at regular time intervals, filtered (Millex GS filter assemblies Millipore, Bedford, MA), and the filtrates analyzed for Ca + (AAS) and PO4 (UV). Upon completion of the immersion tests, the disks were removed, dried, and again characterized by XRD. Variations in the total area of disk surface (A) exposed were taken into account and Ca + and P04 values normalized to an average surface area of 500 mm. ... 

Porphyrins can be lithiated by replacement of the two N—H protons. Dialkali metal salts have been synthesized and characterized by XRD crystallography. The hole-in-the-middle... 

The pillared clays were also characterized by XRD. The [001] reflection characteristic of the expansion of the clay Is due to Insertion of the hydroxyalumlnum polycations between the clay layers. In Figure 5 the traces of the [001] reflection are shown... 

For iron oxides, IR spectroscopy is useful as a means of identification. Hematite crystals in films that were too thin (<70nm) to be characterized by XRD were shown by IR to be oriented with the c-axis perpendicular to the surface of the film (Yubero et al. 2000). This technique also provides information about crystal morphology, degree of crystallinity and the extent of metal (especially Al) substitution because these properties can induce shifts in some of the IR absorption bands. It is also widely used both to obtain information about the vibrational state of adsorbed molecules (particularly anions) and hence the nature of surface complexes (see Chap. 11) and to investigate the nature of surface hydroxyl groups and adsorbed water (see Chap. 10). Typical IR spectra of the various iron oxides are depicted in Figure 7.1. Impurities arising either from the method of preparation or from adsorption of atmospheric compounds can produce distinct bands in the spectra of these oxides -namely at 1700 cm (oxalate), 1400 cm (nitrate) and 1300 and 1500 cm (carbonate). 

Preparation and characterization of two-dimensional zirconium phosphonate derivatives in either crystalline or amorphous forms have been investigated. Two composite zirconium phosphonates in single crystal phase have also been investigated and characterized by XRD, i c-, and 3ip-MASNMR. The catalytic performance over zirconium phosphonates are evaluated by hydrolysis of ethylacetate in aqueous solution. When the composite zirconium phosphonate is composed with an acidic function and with a hydrophobic function in single crystal phase, the catalytic activity in aqueous medium showed higher activity than that of single acidic zirconium phosphonate. The composite materials become accessible to any reactant molecule and improve hydnq>hobicity. 

The iron molybdenum oxide catalyst was structurally characterized by XRD and vibrational spectroscopy (IR and Raman). 

With the aim to study the characteristics of VPO catalysts in the course of butane oxidation to maleic anhydride together with a simultaneous evaluation of the catalytic performance, we have used Raman spectroscopy which is a very sensitive probe for determining the presence of V0P04-like entities together with (VO)2P207. An in situ Laser Raman Spectroscopy (LRS) cell was built in our laboratory (6). In the corresponding publication (6 ), the preparation and the characterization by XRD, Ip... 

Although fly ash is largely non-crystalline glass, the major and minor elements in fly ash (O, Si, Al, Fe, Ca, Mg, and S) foim several different phases that have been characterized by XRD in many research projects (Diamond 1984 McCarthy 1988 Bergeson etal. 1988 Thedchanamoorthy McCarthy 1989 Ainsworth et al. 1993). The phases of major elemental constituents that have been commonly identified in fly ash include quartz mullite, Al6Si20 3 tricalcium aluminate, Ca3Al206... 

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