Of solid samples

Typical examples of solid samples include large particulates, such as those found in ores smaller particulates, such as soils and sediments tablets, pellets, and capsules used in dispensing pharmaceutical products and animal feeds sheet materials, such as polymers and rolled metals and tissue samples from biological specimens. 

Laser ionization. Occurs when a sample is irradiated with a laser beam. In the irradiation of gaseous samples, ionization occurs via a single- or multiphoton process. In the case of solid samples, ionization occurs via a thermal process. 

Neutron-rich lanthanide isotopes occur in the fission of uranium or plutonium and ate separated during the reprocessing of nuclear fuel wastes (see Nuclearreactors). Lanthanide isotopes can be produced by neutron bombardment, by radioactive decay of neighboring atoms, and by nuclear reactions in accelerators where the rate earths ate bombarded with charged particles. The rare-earth content of solid samples can be determined by neutron... 

A solvent free, fast and environmentally friendly near infrared-based methodology was developed for the determination and quality control of 11 pesticides in commercially available formulations. This methodology was based on the direct measurement of the diffuse reflectance spectra of solid samples inside glass vials and a multivariate calibration model to determine the active principle concentration in agrochemicals. The proposed PLS model was made using 11 known commercial and 22 doped samples (11 under and 11 over dosed) for calibration and 22 different formulations as the validation set. For Buprofezin, Chlorsulfuron, Cyromazine, Daminozide, Diuron and Iprodione determination, the information in the spectral range between 1618 and 2630 nm of the reflectance spectra was employed. On the other hand, for Bensulfuron, Fenoxycarb, Metalaxyl, Procymidone and Tricyclazole determination, the first order derivative spectra in the range between 1618 and 2630 nm was used. In both cases, a linear remove correction was applied. Mean accuracy errors between 0.5 and 3.1% were obtained for the validation set. 

Direct atomic absorption spectrometry (AAS) analysis of increasing (e 0,10 g) mass of solid samples is the great practical interest since in a number of cases it allows to eliminate a long-time and labor consuming pretreatment dissolution procedure of materials and preconcentration of elements to be determined. Nevertheless at prevalent analytical practice iS iO based materials direct AAS are not practically used. 

Repeated chromatography on neutral alumina yields minor quantities of solid samples of C76, Cg4, C90 and C94 believed to be higher fullerenes. A stable oxide C70O has been identified. Chromatographic procedures for the separation of these compounds are reported. [Science 2S2 548 7997.]... 

Ardcle No. Technique P- ii o 8 eu 0 3 In Depth prohed (typical) Width probed (typical) Trace capability (typical) Types of solid sample (typical) S 1 T3 H 1 > 8 ... 

Auger electron spectroscopy (AES) is a technique used to identify the elemental composition, and in many cases, the chemical bonding of the atoms in the surface region of solid samples. It can be combined with ion-beam sputtering to remove material from the surface and to continue to monitor the composition and chemistry of the remaining surface as this surface moves into the sample. It uses an electron beam as a probe of the sample surface and its output is the energy distribution of the secondary electrons released by the probe beam from the sample, although only the Ai er electron component of the secondaries is used in the analysis. 

The sensitivity, accuracy, and precision of solid-sample analysis have been greatly improved by coupling LA with ICP-OES-MS. The ablated species are transported by means of a carrier gas (usually argon) into the plasma torch. Further atomization, excitation, and ionization of the ablated species in the stationary hot plasma result in a dramatic increase in the sensitivity of the detection of radiation (LA-ICP-OES) or of the detection of ions (LA-ICP-MS). 

As already remarked in Sect. 4.5.1 (Introduction), LA was primarily designed as a technique for direct sampling in the bulk analysis of solid samples. The main advantages of LA are the possibility of ablating all types of solid material (metals, isolators, glasses, crystals, minerals ceramics, etc.), no special requirements on the... 

The foundation of shock-compression science is based upon observations and analyses of the mechanical responses of solid samples to shock-loading pulses. Although the resulting mechanical framework is necessary, there is no reason to believe that a sufficiently complete scientific picture can be based on mechanical considerations alone. Nevertheless, the base of our knowledge rests here, and it is essential to recognize its characteristics, and critically examine the work. 

Dent et al. [47] also investigated the V K-edge EXAFS for the dissolution of [EMIM][VOCl4] and [NEt4][V02Cl2] in basic [EMIM]C1/A1C13 and compared the data with those of solid samples. In both cases the dissolved and the solid samples showed similar EXAFS and no coordination of the chloroaluminate species to, for example, the vanadyl oxygen was found. 

The Au anion distance of [Au2(dcpm)2][Au(CN)2]2 lies between those with noncoordinating (C104 or PFg ) anions and that of the I salt. The visible emission of the [Au2(dcpm)2] [Au(CN)2]2 solid at 7, = 515 nm is more intense than the visible emission of solid samples of C104 and PF salts of [Au2(dcpm)2] at 564 and 505 nm... 

This mode of chromatogram development is, in principle, almost identical with continuous development. The only feature that varies is the length of the developing path. In short bed-continuous development (SB/CD), this path is very short, typically equal to several centimeters [23-25]. This is the reason why this mode is preferentially applied for analytical separations. However, a similar technique is applied for zonal sample application and online extraction of solid samples, which are described in the following text. 

The procedure described earlier for sample preconcentration can be easily extended for the online extraction of solid samples, e.g., powdered plant materials. Horizontal conbguration of the chromatographic plate in the chamber facihtates this procedure, because the sample to be extracted is then placed on a carrier plate at the begiiming part of the adsorbent layer (or in the scrapped channel of the adsorbent layer), which should be directed upward [15,26]. The chamber is covered with a narrow plate, and the development is started with a snitable extracting solvent. In some cases, it is advantageous to put the narrow plate directly on the adsorbent layer to press the sample to be extracted. Extracted components are preconcentrated on the adsorbent layer at the end of the narrow plate, as shown in Fignre 6.26 [15]. 

Another improvement that will allow quick simultaneous oligoelement homogeneity determinations in milligram samples can be expected by the use of solid sampling ETV-ICP-MS/AES and laser ablation ICP-MS which are now being studied in detail (Moens et al. 1995 Schiffer and Krivan 1999 Dobney et al. 2000). 

Nowka R, Muller H (1997) Direct analysis of solid samples by graphite furnace atomic absorption spectrometry with a transversely heated graphite atomizer and D2-background correction system (SS GF-AAS). Fresenius J Anal Chem 359 132-137. 

Backmank S, Karlsson RW (1979) Determination of lead, bismuth, zinc, silver and antimony in steel and nickel-base alloys by atomic-absorption spectrometry using direct atomization of solid samples in a graphite furnace. Analyst 104 1017-1029. 

Hoffmann E, Ludke C, Scholze H (1997) Is laser ablation-lCP-MS an alternative to solution analysis of solid samples Fresenius J Anal Chem 359 394-398. 

Noweoy R, Marr IL, Ansari TM, Muller H 1999) Direct analysis of solid samples by GFAAS -determination of trace hea-vy metals in barytes. Fresenius ( Anal Chem 364 533-540. 

Pauwels J, Hofmann C, Vandbcasteele C (1994) Calibration of solid sampling Zeeman atomic absorption spectrometry by extrapolation to zero matrix. Fresenius J Anal Chem 348 418-421. 

Rossbach M, Ostapczuk P, Emons H (1998) Microhomogeneity of candidate reference materials Comparison of solid sampling Zeeman-AAS with INAA. Fresenius J Anal Chem 360 380-383. Rossbach M, Stoeppler M (1987) Use of CRMs as mutual calibration materials and control of synthetic multielement standards as used in INAA. J Radioanal Nud Chem Artides 113 217-223. Sargent M (1995) Development and application of a protocol for quality assurance of trace analysis. Anal Proc 32 71-76. 

Verrept P, Dams R, Kurfurst U 1993) Electrothermal vaporisation inductively coupled plasma atomic emission spectrometry for the analysis of solid samples contribution to instrumentation and methodology. Fresenius 2 Anal Chem 345 1035-1041. 

Distillation is a suitable technique for the isolation of volatile organic compounds from liquid samples or the soluble portion of solid samples [24,27-30]. The physical basis of separation depends on the distribution of constituents between the liquid mixture and the vapor in equilibrium with that mixture. The more volatile constituents are concentrated in the vapor phase, which is collected after condensation. The effectiveness of the separation is dependent on the physical properties of the... 

To obtain representative samples from nonhomoge-neous sample materials, such as polymer compounds, particle-size reduction techniques need often to be applied (not for film) [50]. Also, for destructive inpolymer additive analysis it is advantageous to change the physical state of solid samples to provide a larger surface area per unit mass. Complete extraction is sometimes achieved only after grinding the sample. Typically, Perlstein [51] has reported recoveries of only 59 % for extraction of Tinuvin 320 from unground PVC after 16 h of Soxhlet extraction with diethyl ether while recoveries rise to 97 % for ground polymer. 

Table 3.4 summarises the main characteristics of a variety of sample preparation modes for in-polymer additive analysis. Table 3.5 is a short literature evaluation of various extraction techniques. Majors [91] has recently reviewed the changing role of extraction in preparation of solid samples. Vandenburg and Clifford [4] and others [6,91-95] have reviewed several sample preparation techniques, including polymer dissolution, LSE and SEE, microwave dissolution, ultra-sonication and accelerated solvent extraction. 

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