Resin extract

Extraction of rosin. Rosin resins are produced from three types of rosin, i.e. gum, tall oil, and wood. Extensive details about rosin resins extraction and derivatization can be found on page 269 in the book edited by Zinkel and Russell [18]. 

Air Collect on XAD-4 macroreticular resin extract with ethyl acetate GC/NPD 0.2 ng/m 85-111 Seiberet al. 1989... 

Water (run-off) Collect on XAD-2 macroreticular resin extract with diethyl ether HPLC/UV 2-3 pg/L 99.75 vi Paschal et al. 1977 > > —... 

Figure 4.17 Substrate adsorption synthesis of ((S)-3,4-methylenedioxyphenyl)-2-propanol from 3,4-methylenedioxyphenylacetone applying a batch process followed by a filtration step and resin extraction...

Simple removal of the catalyst using ion-exchange resins, extractions with water or polymer precipitation [148,149,150,151]... 

More recent approaches have used resin extractions, initially the nonionic resin XAD2 and XAD7. These resins are effective where the pH was kept at 10 while mixing the plasma and resin. The supernatant is discarded and the bile... 

Experiments to identify disinfection by-products (DBFs) have been carried out using two different procedures. In the first, natural waters (e.g., river, lake) are reacted with the disinfectant, either in a pilot plant, an actual treatment plant, or in a controlled laboratory smdy. fii the second type of procedure, aquatic humic material is isolated and reacted with the disinfectant in purified water in a controlled laboratory study. This latter type of study is relevant because humic material is an important precursor of THMs and other DBFs. Aquatic humic material is present in nearly all natural waters, and isolated humic material reacts with disinfectants to produce most of the same DBFs found from natural waters. Because DBFs are typically formed at low levels (ng/L-pg/L), samples are usually concentrated to allow for DBF detection. Concentration methods that are commonly used include solid phase extraction (SFE), solid phase microextraction (SFME), liquid-liquid extraction, and XAD resin extraction (for larger quantities of water) [9]. 

The first moment of the distribution is Pt0T the total, cumulative molar concentration of polymeric material. As the molecular weight of polymeric species increases, branching and crosslinking reactions yield a thermoset resin. Chromatography analysis of epoxy resin extracts confirms the expected population density distribution described by Equation 4, as is shown in Figure 2. Formulations and cure cycles appear in Table II. 

Phosphate must be applied as fertilizer to the soil. Ideally it is added in quantities sufficient to guarantee optimal yields, but not in excess in order to avoid P transportation into other compartments of the ecosystem. The amount added should be based on an accurate estimation of the plant-available fraction of P already present in a soil.This is an old and difficult task and a large number of extraction methods have been used since intensive land use was practised. Recently methods have been worked out in which a strip of filter paper impregnated with an Fe oxide (2-line ferri-hydrite) is dipped into a soil suspension and the amount of P adsorbed by the paper is taken as being plant-available (Sissingh,1988 Van der Zee et ah, 1987 Sharpley, 1993 Sharpley et ah,1994 Kuo and Jellum, 1994 Myers et ah 1997). Anion and cation resins extracted more P from four heavily fertilized soils than from goethite (Delgado Torrent, 2000). Other oxyanions adsorbed by soil Fe oxides are silicate, arsenate, chromate, selenite ( ) and sulphate. Adsorption of sulphate led to a release of OH ions and was substantially lowered once the Fe oxides were selectively removed (Fig.16.17). 

Fig. 5.4. Manifold for the automated determination of phosphorus in soil resin extracts. 

Calculation. The 2-ml scoop of soil was extracted via resin into 50 ml sodium sulphate extractant therefore the concentration must be multiplied by 25 to give the pg P ml in soil by resin extraction. Hislop and Cooke (1968) classified the soils with respect to mg P h air-dry soil as follows ... 

Toxic nitrophenols (4-nitrophenol, 2-nitrophenol, and 2,4-dinitrophenol) present in air samples are sampled on silica gel or XAD-2 polymeric resin, extracted, and analyzed by the HPLC/DAD technique [240], Nitrophenols are also determined in rain and snow precipitations through HPLC/ UV analysis after SPE [241]. 

Urine Polydithiocarbamate resin extraction ash fdter and resins in a low temperature oxygen plasma asher or digest with HN03 HCL04 ICP-AES NIOSH 8310 0.1 pg/sample 80% NIOSH 1994b... 

Toluene Feedstock, paints, resins, extractants, gasoline additive Narcotic in high concentrations 200 7.53 g/kg... 

Balsam turpentine oil is obtained from the resins of living trees of suitable Pinus species by distillation at atmospheric pressure and temperatures up to 180°C, or by other fractionation methods, which do not change the terpene composition of the resins. Wood turpentine oils, on the other hand, are generally obtained by steam distillation of chopped tree trunks, dead wood, or of resin extracted from this wood. Sulfate turpentine oil is produced as waste in the manufacture of cellulose by the sulfate process and is also a wood turpentine. Pine oil is another wood turpentine oil that is obtained by dry distillation of suitable pine and fir trees, followed by fractionation. However, the term pine oil is nowadays used for a product which is manufactured by hydration of turpentine oil (a-pinene). The resulting product is a mixture of monoterpenes containing o-terpineol as the main component. In addition to many other technical purposes, it is used to a large extent in cheap perfumes for technical applications. 

Artifacts from the resin can interfere with the chromatographic analysis of the XAD resin extract. For example, the artifact may be a pollutant being studied, or coelution of the resin artifacts and compounds of interest may occur during capillary gas chromatographic (GC) analysis. Artifacts can also take part in competitive adsorption during sampling. This situation can cause sample breakthrough because certain compounds are preferentially collected. 

Broad Spectrum Analysis of Resin Extracts A Base Extraction Cleanup Procedure... 

A base extraction procedure was developed to minimize the degradation of the performance of fused-silica capillary chromatographic columns used to analyze XAD resin extracts. The degradation of the capillary gas chromatographic column was apparently caused by acidic nonvolatiles called humic materials. The humic materials were absorbed on XAD resins and eluted by nonpolar solvents along with the nonpolar organic compounds of interest in the samples. The base extraction procedure removed approximately 84% of the humic materials present in the ether extract. 

This chapter describes the simpler cleanup approach of base extraction for XAD resin extracts. Quality assurance procedures statistically define the benefits of this analytical approach for broad spectrum capillary GC. The extraction procedure was optimized by studying UV absorbance of the base extractant. 

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