Sample preparation drying

Sample preparation Dried greater celandine was pulverized and briefly boiled in 0.05 mol sulfuric acid. After cooling to room temperature the mixture was placed in a separating funnel and adjusted to pH 10 with ammonia solution and extracted once with chloroform. The organic phase was dried with sodium sulfate and evaporated to dryness under reduced pressure. The residue was taken up in methanol and used as the sample solution for TLC. 

SAMPLE PREPARATION. Dry Illinois No. 6 (Herrin seam, -60 mesh) was used in the sorption studies. Analysis Found C, 74.37 H, 4.83 N, 1.76 S, 1.76 O (by difference), 8.74 Ash, 8.33 (duplicate). Approximately 10 g of the sample was exhaustively Soxhlet extracted with pyridine. Extractability was 18.7% (wt). The pyridine solution was then filtered through a 0.4 /xm filter to insure removal of particulates and colloidal material. The filter did not plug. Most of the pyridine was removed by rotovaporization under reduced pressure at 70-80 C. Approximately 200 mL of a methanol/water (80/20 vol) mixture and 2 mL of cone. HCl were added to the flask and the mixture was stirred under nitrogen for two days. The solid extract was then filtered and dried under vacuum at 105 "C for 24 hours. Analysis Found C, 80.0 H, 5.64 N, 1.85 S, 0.70 Ash, 0.30 (duplicate). 

Sample preparation Dry pack 60 x 8 mm glass columns with 250 mg Carbopack B (200-400 mesh) and 60 X 4 mm glass colvunns with 50 mg Amberlite CG-4001 (100-200 mesh). Wash Carbopack column with 5 mL MeOH, 15 mL dichloromethane MeOH 70 30, and MeOH. water 85 15. Wash Amberlite column with 3 mL 0.5 M NaOH, 8 mL... 

Sample preparation Dry tear sample under nitrogen. 

Generally as in the case of soils two approaches may be used for sampling preparation dry ashing and acid digestion. 

The experimental details of these derivatization reactions are presented in some well-known specialized texts.The first two reactions mentioned are sensitive to the presence of water in the samples (typical silylation and acylation reagents react with water more quickly than with the target organic compounds) and usually cannot proceed in aqueous media. The analysis in these conditions typically requires special sample preparation (drying before derivatization). 

Sample preparations Dried and coated with gold or carbon Lightly coated with platinum Not required Thinly sliced and stained... 

Artifacts introduced through sample preparation are common materials these may be bits of facial tissue, wax, epithelial cells, hair, or dried stain, all inadvertently introduced by the microscopist. Detergent residues on so-called precleaned microscope slides and broken glass are common artifacts, as are knife marks and chatter marks from sectioning with a faulty blade, or scratch marks from grinding and polishing. 

The mycelium (56 g dry weight) was filtered off and the steroidal material was extracted with methylene chloride, the methylene extracts evaporated to dryness, and the resulting residue chromatographed over a Florisil column. The column was packed with 200 g of Florisil and was developed with five 400-ml fractions each of methylene chloride, Skelly-solve 8-acetone mixtures of 9 1, 8 2, 7 3, 1 1, and methanol. The fraction eluted with Skellysolve 8-acetone (7 3) weighed 1.545 g and on recrystallization from acetone gave, in three crops, 928 mg of product of MP 210° to 235°C. The sample prepared for analysis melted at 245° to 247°C. 

Carbon Dioxide Adsorption on Dried Polymer. Other unexpected interactions of these hydrolytic polymers have been noted previously during the measurement of infrared spectra of dried Pu(IV) polymers (like those used for diffraction studies). Vibrational bands first attributed to nitrate ion were observed in samples exposed to room air however, these bands were not present in samples prepared under nitrogen atmospheres (see Fig. 4) (6). Chemical analyses established enough carbon in the exposed samples to confirm the assignment of the extraneous bands to the carbonate functional group... 

Several solid surfaces, such as filter paper, sodium acetate, and silica gel chromatoplates with a polyacrylate binder, have been used in solid-surface luminescence work (1,2). Experimentally it is relatively easy to prepare samples for analysis. With filter paper, for example, a small volume of sample solution is spotted onto the surface, the filter paper is dried, and then the measurement is made. In many cases, an inert gas is passed over the surface during the measurement step to enhance the RTF signal. For powdered samples, the sample preparation procedure is somewhat more involved. Commercial instruments can be readily used to measure the luminescence signals, and a variety of research instruments have been developed to obtain the solid-surface luminescence data (1,2). 

In this case, three particles are shown, a 40 u, 20 p and a 10 p particle. The most important step is sample preparation on the microscope slide, since only a pinch of materied is used, one must be sure that the sample is uniform and representative of the material. Also, since most materials tend to agglomerate due to accumulated surface charge in a dry state, one adds a few drops of alcohol and works it with a spatula, spreading it out into a thin layer which dries. Too much working breaks down the original peirticles. 

In this paper we report (i) the catalytic activity for SCR of VOx/Zr02 samples prepared by various methods (adsorption from aqueous metavanadate solutions at different pH values, dry impregnation, and adsorption from VO(acetylacetonate)2 in toluene), (ii) sample characterization (nuclearity, dispersion and oxidation state) by means of XPS, ESR and FTIR and (iii) the nature and reactivity of the surface species observed in the presence of the reactant mixture. Catalytic results are here reported in full. Characterization data relevant to the discussion of the catalytic activity will be given, whereas details on the catalysts preparation and... 

Sample preparation for analyses Introduces some possibilities for errors. Vegetation, sod, or other non-soil material must be removed from the sample. This Is followed by grinding or mixing the sample In some way, sieving It, and then drying It when necessary. 

Sample preparation for AFM analysis is relatively simple. Generally, a desired amount of sample is absorbed onto a smooth and clean substrate surface, for example, a freshly cleaved mica surface. For example, to prepare a food macromolecule sample for AFM imaging in air, the diluted macromolecule solution is disrupted by vortexing. Then, a small aliquot (tens of microliters) of vortexed solution is deposited onto a surface of freshly cleaved mica sheet by pipette. The mica surface is air dried before the AFM scan. A clean surrounding is required to avoid the interference of dust in the air. Molecular combing or fluid fixation may be applied to manipulate the molecule to get more information. 

The confirmatory procedure should be developed for the same tissues for which the determinative procedure was developed, preferably using the same extraction procedure as used for the determinative portion of the method. Storage and stability data are necessary for dried or liquid sample extracts if MS analyses of the confirmatory samples are to be conducted in a laboratory other than the laboratory of sample preparation. Analytes present in sample extracts must be stable long enough for the samples to be shipped to the MS laboratory and analyzed. 

SFE of fruits and vegetables and meat products has been reported, but the sample preparation techniques necessary to obtain reproducible results are extremely time consuming. Solid absorbents such as Hydromatrix, Extrelut " anhydrous magnesium sulfate or absorbent polymers are required to control the level of water in the sample for the extraction of the nonpolar pesticides. Without the addition of Hydromatrix, nonpolar pesticides cannot penetrate the water barrier between the sample particles and the supercritical CO2. The sample is normally frozen and the addition of dry-ice may be required to reduce losses due to degradation and/or evaporation. Thorough reviews of the advantages and limitations of SFE in pesticide residues... 

No specific sample preparation or processing is needed for this method. In general, fruits and vegetables were macerated with dry-ice and placed into freezer storage prior to extraction. 

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