Sample X-ray diffraction

The method for the study of crystal structure, including mineral composition, is x-ray diffraction. It is a semiquantitative method (Klug and Alexander 1954 Warren 1999) for the study of mineral composition. Powder samples of rocks are studied, and the place of the peaks (in nanometer or diffraction angle) and their relative intensity are observed. The diffractogram is usually compared to that of known substances that can be found in databases (ICDD 2009). In order to accurately quantify the rock samples, x-ray diffraction must be complemented with other quantitative techniques, including chemical analysis (Section 4.1.1), thermal, infrared analyses (Chapter 2, Section 2.1.2) and surface area (Chapter 1, Section 1.3.4.1.5 Section 4.1.3) measurements. 

For bones that had been buried in contact with the soil, a scanning electron microscope (SEM) (JSM-35) was used to examine the samples. A Kevex X-ray system (Si(Li) detector and associated analytical programs) was used to provide semiquantitative analysis of particles observed with the SEM. This analysis, along with the crystal morphology, were used to identify the minerals in the bone samples. X-ray diffraction with Cu-Ka radiation (Ni filter) provided information on the minerals in the bulk bone samples. Powder patterns were obtained with a Phillips diffractometer. 

Warm water washing of polymer-CD-ICs containing polymer guests insoluble in water or treatment with amylase enzymes serves to remove the host CDs and results in the coalescence of the guest polymers into solid samples. X-ray diffraction, DSC, TGA, and FUR and NMR spectroscopies are typically used to characterize the coalesced polymer samples. 

The composition of the deposited solder was measured by energy dispersive x-ray measurements using standards in a scanning electron microscope. For each deposit, four square regions measuring 1.5 mm per side were sampled. A scanning electron microscope with a field emission source was employed for the micrographs of the samples. X-ray diffraction measurements were also made on selected samples, in order to determine the structure and orientation of the deposits. 

To identify the crystalline phases that were present in the raw and fired samples. X-ray diffraction patterns were collected using a conventional powder technique in a Siemens Diffractometer (D500 mod) employing Cu K.a Ni-filtered radiation. To define the color developed about the samples, a UV-Vis spectrophotometer with analytical software for color measurements (PERK-fN ELMER Spectrometer Lambda 19, UV/VIS/NIR, Standard Observer 10°) has been used. L, a, b color parameters have been measured following the CIE (Commission International de I Eclairage) colorimetric method. In this method, L is the lightness axis (black 0)—>white (100)), a is the green (-) —>red (-H) axis, and b is the blue (-) — yellow (-r) axis. 

Glass slides vertically immersed into the biominerahzation media (at 37°C) similar to amino acids-, vitamins-, Hepes-, glucose/dextrose-, pymvate-free DMEM solution were covered with a monolayer of calcium phosphate visible to the naked eye in 48 h (Fig. la). Glass slides kept in the solutions for only 24 h (data not shown) were also covered with CaP (calcium phosphate) but the surface coverage was not as complete as those of 48 h samples. X-ray diffraction (XRD) analyses showed that the deposited CaP was x-ray- amorphous (Fig. lb). The large hump (from 10 to 40° 20) seen in Fig. lb was due to the base sUicate glass. Solution-precipitated CaPs (such as those obtained in SBF solutions) typically exhibit moderately high intensity X-ray peaks at 25.89° and at 31.78-to-34.05° 20, and such apatitic CaP peaks were absent in Fig. lb. 

Early chemical profiling attempted to establish batch links among illicit drug seizures by comparative studies, based on both qualitative and quantitative information, although success in achieving this has been varied. Such studies have been applied to link heroin and cocaine samples to common origins, based on the concentration of the organic impurities present. Isotopic analysis of impurities and intermediates has been employed in the comparison of seized heroin, methamphetamine, and ecstasy samples. X-ray diffraction and NMR spectroscopy (both and have been used to... 

Our laboratory at the University of Vermont has successfully grown Ru02 nanorods by reactive sputtering on Si wafer substrates with a variety of pre-existing surface conditions. Proof of a crystalline structure has been obtained by X-ray diffraction. A sample X-ray diffraction spectrum of the deposited nanorods is shown in Fig. 3. Each of the major peaks in Fig. 3 corresponds to a single crystal orientation of the nanorods. Although each nanorod is single crystal, each nanorod is randomly ori-... 

In order to establish the existence of supermolecular structures in the test sample. X-ray diffraction techniques suggested by Alexander [23] were used. Using a General Electric X-ray unit, rubber samples were exposed at various stretch ratios and temperatures to a 0.025 -diameter beam of nickel filtered Cu Ka radiation (50KV, 20MA). X-ray diffraction photographs (5cm film-to-target distance) were taken at one hour exposures. The samples were... 

---