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A good analytical chemistry research paper may be defined as one that passes the critical review of one's peers for publication in a recognized reviewed jour-nal. Factors to consider in publishing an analytical paper include careful selection of the right journal, clear concise presentation that emphasizes the re-search contribution and its significance to the field, and careful revision if called for to account for the reviewers' and editors' criticisms. Rather special requirements apply to methods papers as opposed to other types of analytical papers. Data should be included to establish the accuracy and precision of the method by the use of standard reference mate-rials, standard addition studies, interference studies, and comparisons with established methods. Day-to-day and run precision studies of the proposed method in a real setting help validate the method. Common problems with analytical papers are discussed. Specific suggestions are given for improving the likeli-hood of publication. Data are given on the ultimate disposition of manuscripts submitted to Analytical Chemistry. Reasons for rejection of papers submitted to the journal are summarized. [ABSTRACT FROM AUTHOR]

A reproducible paper chromatographic procedure has been developed for resolving a mixture consisting of 1-mono-, 1,3-di-, and triglycerides, cholesterol, and cholesteryl esters. The separation is accomplished, using silicic acid impregnated glass fiber filter paper as the chromatographic medium and various ethyl ether-isooctane mixtures as the solvent systems. A reagent consisting of 1:1 concentrated sulfuric acid: water has been introduced for visualizing the lipides on the chromatogram and for distinguishing between glycerides and cholesterol-containing lipides. Unsaturation in the fatty acid moiety of the mono-, di-, and triglycerides had no detectable effect on the R values of these substances. Fatty acid chain length did not affect the R of the cholesteryl esters with the solvent systems studied. Increasing the percentage ethyl ether in the solvent system caused an increase in the R values of each lipide not moving at the solvent front. [ABSTRACT FROM AUTHOR]

A method is described by which unsaturated fatty acid esters can be separated and identified by reversed-phase paper chromatography. The procedure is based upon the formation of the mercuric acetate addition compounds of the esters and the detection of the compounds on the chromatograms, using the sensitive color reaction with diphenylcarbazone. The application of this technique to the analysis of the component unsaturated acids of natural fats has been examined, and tetradecenoic acid in olive oil and hexadecenoic acid in linseed oil both formerly unidentified have been detected as the minor component acids by means of the method. The preliminary investigation on the absorption spectra of diphenylcarbazone complexes derived from the addition compounds has been made to bring the method into quantitative use. [ABSTRACT FROM AUTHOR]

Paper chromatography has been found to be a very satisfactory method for the separation of glycerine from hexitols, pentitols, tetritols, and glycols. After separation of the glycerine on paper the glycerine is eluted from the indicated zone with water. The formaldehyde, which is a product of periodic acid oxidation, is determined colorimetrically. A suggested procedure and the results of the analyses of standard glycerine and polyhydric alcohol mixtures are presented in this paper. The results indicate that the glycerine content of the mixtures (glycerine content ranging from 15% to 100% glycerine) may be determined with an average relative precision of 0.7% and with an average recovery of 101.0%. [ABSTRACT FROM AUTHOR]

Despite the increasing importance of nonionic surfactants, methods for their identification have been limited to specific groups. Accordingly, a general analytical scheme for the identification of polyoxyalkylene-type nonionic surfactants was developed, which uses qualitative tests and two paper chromatographic solvent systems. This procedure differentiates among the ethoxylates of alcohols, thioalcohols, alkyl phenol, fatty acids, polyoxyethylene polyoxypropylene acids, sorbitan fatty esters, fatty amides, polyoxyethylene glycols (PEG) condensates. In addition, individual members of a class can be separated and identified. The method is applicable to a variety of detergent products and to mixtures of more than one nonionic. As little as 7 mg of a nonionic surfactant are sufficient for complete characterization. [ABSTRACT FROM AUTHOR]

A rapid method of separating the 2,4-dinitrophenylhydrazones of C to C aldehydes by descending chromatographic system has been described. Whatman No. 1 filter paper was impregnated with ethylene glycol-methanol (1∶4, v/v), and n-heptane saturated with methanol was used as a developing solvent. Complete separation was achieved in 3 hrs. It has been shown that the method can also be used for the separation of 2,4-dinitrophenylhydrazone derivatives of ketones. [ABSTRACT FROM AUTHOR]

Procedures for qualitative and quantitative paper chromatography of lipides have been described in detail, together with some practical applications. With the monochain lipides it was found that one developing system serves universally. The long aliphatic chains essentially determine the chromatographic properties so that suitable conditions for chromatographing any lipide or lipide-like entity are predictable. For the same reason total analysis of natural mixtures cannot be done on one paper chromatogram due to superpositions. For complete analysis of natural mixtures of fatty acids it is advisable at the present time to combine paper chromatography with some other separation method. Distillation supplements best but requires gram quantities of material while paper chromatography is applicable on gamma or milligram scale. Chain-length analysis by paper chromatography and low-temperature chromatography have been introduced and are promising methods to approach a completely micro method for analyzing complex mixtures. [ABSTRACT FROM AUTHOR]

1. A reasonably reproducible method has been developed for separating lysolecithin, lecithin,, sphingomyelin, and phosphatidylethanolamine, using glass fiber filter paper impregnated with silicic acid as the chromatographic medium and 1:1 methanol:ethyl ether as the developing solvent. 2. Hot sulfuric acid was used to locate the chromatographed compounds on the chromatogram. The advantages and disadvantages of this reagent and the other spot test reagents used were discussed. 3. No separation between the unsaturated and saturated counterparts of lysolecithin or lecithin was obtained. [ABSTRACT FROM AUTHOR]

A degree of reverse phase separation of triglycerides can be obtained with ascending chromatography on uncoated glass paper using a pyridine: water solvent system. The same R values result when silica gel coated paper is used. To extend the usefulness of this separation, the glyceryl esters are converted to methyl esters in situ using sodium methoxide. This permits, on silica gel coated paper, glyceryl ester separation in one dimension, eslatography to the methyl esters, and methyl ester separation in the second dimension. In mixtures of lipids such as serum extracts, the lipid groups may be separated in one dimension and the fatty acid methyl esters in the second dimension. [ABSTRACT FROM AUTHOR]

A quantitative paper chromatographic method was worked out for determining small amounts of trimethyloctadecyl quaternary ammonium chloride in dimethyldioctadecyl quaternary ammonium chloride. With a mixed solvent containing methanol, acetone, and water, the trimethyl-type quaternary travels just behind the solvent front, whereas the dimethyl-type quaternary and other components move very little. The trimethyl quaternary spot is developed with bromphenol blue and the resulting color is measured photometrically at 607 mμ. Standards are run on either side of the sample spot and are used for quantitative calibration. Accuracy and reproducibility of the method appears to be within 0.4% absolute. [ABSTRACT FROM AUTHOR]

An integrated system using chromatography on silica gel-impregnated glass paper, an internal standard and gas-liquid chromatography (GLC) makes possible the isolation of triglycerides, the determination of triglyceride, fatty acid composition, and the quantitative determination of triglyceride. Recoveries are good and values for total triglyceride obtained by this system compare favorably with values obtained by application of the hydroxamate colorimetric method to the triglyceride eluate from silicic acid columns. The fatty acid composition of the cholesteryl ester (CE) fraction is obtainable at the same time by GLC of methyl esters prepared from the CE fractions which also appears as a distinct spot on these chromatograms. Also, a densitometric method is described for triglyceride determination by photometry of the charred spots obtained after chromatography on the gel-paper. [ABSTRACT FROM AUTHOR]

A quantitative method for the determination of traces of free gossypol in oils and fatty acids was developed. The method is based on the concentration of gossypol by extraction and quantitative paper chromatography of the extract. The method is specific for free gossypol and is not subject to interferences. The new method is both accurate and reproducible. The lower limit of detection is 10 p.p.m. The method is intended primarily for p.p.m. levels but is suitable for all concentrations. With slight modifications the method is applicable to meals. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Kinetics Studies on Oxirane Cleavage of Epoxidized Soybean Oil (ESO) by Methanol and Characterization of Polyols," published in a previous issue.

Paper coated with peanut protein adhesive and mineral pigments gives high wax pick tests. Critical factors affecting the wax pick value are the type of protein, pigment, and dispersing agent, pH, protein-pigment ratio, and total solids content of the slip. When neutralized protein is used as the adhesive, coating slips containing 40% solids may be prepared with pH values as low as 6.3; and when these slips are applied to raw stock, the coating has wax pick values satisfactory for many printing operations. Over a pH range of 8 to 12, coatings prepared from unwashed protein give high wax pick values, whereas those prepared with water-washed protein give slightly lower values. [ABSTRACT FROM AUTHOR]

A novel accelerated method to assess the dispersion instability of oil‐in‐water (O/W) emulsions with a high oil content such as mayonnaise and mayonnaise‐like semisolid dressing was developed. The method focuses on oil–water separation of the emulsions due to the increase in the ionic strength of the aqueous phase by evaporating the water under vacuum. The oil, separated from the emulsion, was absorbed with a filter paper. The oil penetration length increased in proportion to the square root of time after a certain time delay, while pure oil was absorbed with the filter paper with no delay. The time delay was defined as the destabilization time when the oil–water separation started to occur. A longer destabilization time represented higher dispersion stability. The destabilization time was longer for the mayonnaise‐like semisolid dressing containing a thickener, and was shorter for the mayonnaise stored for a longer duration. It is suggested that the effect of the composition of the aqueous phase on instability can be examined by the method. [ABSTRACT FROM AUTHOR]

The effects of the agitation conditions and headspace‐to‐emulsion volume ratio on lipid oxidation in emulsions can be considerable, but have not been systematically investigated yet. In the current paper, lipid oxidation was monitored in model oil‐in‐water (O/W) emulsions at pH 4.0 and 25°C in the presence of 200 μM iron sulfate. The formation of primary (conjugated dienes and hydroperoxides) and secondary (p‐anisidine value and TBARS) oxidation products confirmed that using rotating or shaking devices doubled the rate of oxidation product formation compared to a non‐agitated system, as a result of enhanced oxygen transfer. Furthermore, we found that a higher headspace‐to‐emulsion volume ratio at least doubled the rate of lipid oxidation due to a higher amount of oxygen available per mass of oil, which is in agreement with the kinetics of the reaction. This indicates that the variation in literature data on lipid oxidation in emulsions can be attributed to differences in mixing conditions and volume ratios. These factors are crucial and should be reported systematically along with the agitation conditions, and sampling method. This will enable a better comparison of literature information. [ABSTRACT FROM AUTHOR]

Pollution preventive measures should be built into the process when a new mill is designed; corrective measures must be taken on existing mills. For air pollution control, these measures consist essentially of enclosing all vessels that contain the black liquor from which the tall oil is recovered. Hoods are placed over storage tanks, sumps, heat exchangers, and other liquor-containing vessels. The hoods must be vented to a ductwork system that brings the off-gases to a central point for disposition. Typical devices to remove the offensive odors and particulate matter in the off-gases are wet scrubbers and incinerators. Evaporation can be used to concentrate liquids containing small amounts of contaminants to much smaller volumes and to concentrations that permit incineration. The lime kiln and recovery boiler of the typical Kraft mill commonly are used to burn the odorous gases, thus destroying the odors completely. Sometimes a separate incinerator is required. Water pollution is best prevented by careful design and operation of the various tall oil removal equipment, such as soap skimmers, level controls, and valving systems. In spite of great care in design and operation, some tall oil will enter the wastewater stream. The effluent treatment plant must be designed to take care of this residual biochemical oxygen demand load and, in some cases, provide for color reduction in the treated effluent. [ABSTRACT FROM AUTHOR]

Paper chromatographic procedures are described, whereby a homologous series of n-aliphatic gamma lactones from butyrolactone through dodecalactone can be resolved as hydroxamic acid derivatives. Similar resolutions can be obtained with a series of n-aliphatic delta lactones from nonalactone through dodecalactone. Procedures also are described, whereby lactones in the presence of ester or glyceride material can be identified using a modified hydroxylamine reagent. Analyses of commercial synthetic peach extracts demonstrate the practical use of these procedures. [ABSTRACT FROM AUTHOR]

A consideration of the economics of installing a leaf type of filter for crude oil in a new mill or as a replacement for existing filtration equipment must take into account the following advantages which a pressure leaf filter offers: [ABSTRACT FROM AUTHOR]

A method for the complete separation and apparent quantitative recovery of both phosphatidyl ethanolamine and phosphatidyl serine from lipid extracts of beef brain is presented. Evidence for the purity, quantitative recovery, and the suitability of the technique for the subsequent analysis of the fatty acid and fatty aldehyde composition of the phospholipids is described. [ABSTRACT FROM AUTHOR]