bluuebunny/crossref_metadata_2025_split huggingface dataset:
The photometric determination of phosphorus in fertilizers using the phosphovanado‐molybdate complex
Authors: Hanson W. C. 
Published: November 2006

AbstractThis rapid method makes use of the stable yellow colour complex developed when an excess of a molybdate solution is added to an acidified solution of a vanadate and an orthophosphate; all three reagents required can be used in a composite solution. Details for the determination of water‐soluble and total phosphate are given using the Spekker photoelectric absorptiometer. Results agree within 2.5% of those obtained by the standard gravimetric method, those on nine fertilizers being given.
A modified phenoldisulphonic acid method for determining nitrates in soil extracts etc.
Authors: Eastoe J. E. , Pollard A. G. 
Published: November 2006

AbstractThe standard phenoldisulphonic acid method of Chamot and Pratt is modified, the nitration being carried out in aqueous solution. A photoelectric method of measuring the colour intensity is employed. The modified method is very rapid in use and has a greatly reduced susceptibility to interference by chlorides or by precipitation of metallic hydroxides and phosphates. The effect of variations in technique is examined and a study made of the level at which interference takes place with the more commonly occurring ions. The general applicability of the method is discussed.
A colorimetric method for the determination of potassium and its application to the analysis of soil extracts
Authors: Whittles C. L. , Little R. C. 
Published: November 2006

AbstractA colorimetric procedure is described for the determination of small amounts of potassium. The soil is extracted with Bray's extracting reagent and the available potassium is precipitated as cobaltinitrite. The determination of potassium precipitated involves the diazotization of sulphanilic acid, using the nitrite groups, of the cobaltinitrite precipitate, and subsequent coupling with dimethylaniline to give methyl orange. The colour is measured with a Spekker absorptiometer. The method is applicable to the routine determination of potassium in soil extracts.
The determination of soluble carbohydrate in dried samples of grass silage by the anthrone method
Authors: John A. , Barnett G. , Miller T. B. 
Published: November 2006

AbstractA method is described for the determination of the soluble carbohydrate content of dried samples of grass silage, using the anthrone reaction. The procedure described below is substantially similar to that of Morris except that modifications required for stabilization of the colour developed were used and a Hilger Spekker absorptiometer was the instrument selected for making the determinations. The silage extracts used were partial hydro‐lysates obtained by heating the dried material with o‐25N‐H2SO4 for a short period.
The determination of starch by acid hydrolysis
Authors: Pirt S. J. , Whelan W. J. 
Published: November 2006

AbstractGlucose is slowly destroyed when heated in neutral solution and the rate of destruction is accelerated by sulphuric acid, but to a much greater extent by hydrochloric acid. Sulphuric acid has therefore been chosen as a suitable starch‐hydrolysing agent and conditions of hydrolysis have been developed whereby starches may be estimated with a high degree of accuracy. A factor, which is almost unity, is used to correct for the loss of glucose by acid degradation. The method has been applied to potato amylose and amylopectin.
Oxidation in apple juice. I.—Preliminary investigation of the relationship between the dissolved‐oxygen content and oxidation of apple juice during processing and shelf‐life in bottle
Authors: Marshall C. R. 
Published: November 2006

AbstractMethods for estimating dissolved oxygen in beer and for measuring the reducing activity of beer have been applied to the study of oxidation in apple juice during processing and throughout its shelf‐life in bottle. Freshly pressed juice is highly oxidized but becomes less so after clarification and filtration. Juices differ in their ability to absorb additional oxygen during processing and there is a protracted time‐lag between absorption and increase in oxidation. In general, after bottling, oxidation increases unless the juice is pre‐heated before the bottles are sealed. After long storage in bottle, apple juice becomes strongly reducing, dissolved oxygen diminishes and a sediment is thrown. Hazes and deposits develop less rapidly in pasteurized juices than in those bottled by sterile filtration and are generally less intense if either air‐space in the bottle or excess oxygen in the juice is reduced.
The chrysanthemumcarboxylic acids. III.—Lactonization of the chrysanthemic acids
Authors: Crombie L. , Harper S. H. , Thompson R. A. 
Published: November 2006

Abstract(±)‐cis‐Chrysanthemic acid is readily lactonized in boiling dilute sulphuric acid to the crystalline (±)‐cis‐dihydrochrysanthemo‐δD‐lactone. The lactone ring is opened by alkali hydrolysis and a derivative of the (±)‐cis‐δD‐hydroxydihydrochrysanthemic acid is obtained. With methanolic sulphuric acid the lactone ring is opened to give mainly methyl (±)‐cis‐±‐methoxydihydrochrysanthemate together with methyl (±)‐cis‐chrysanthemate.In contrast, (±)‐trans‐chrysanthemic acid is converted under similar conditions into the crystalline (±)‐trans‐δ‐hydroxydihydrochrysanthemic acid.The mechanisms of these reactions and their bearing on the Seil and the Wilcoxon–Holaday methods of pyrethrum assay are discussed.On heating at 300° C. in sealed tubes (±)‐cis‐and (±)‐trans‐chrysanthemic acids and (±)‐cis‐dihydrochrysanthemo‐δ‐lactone are converted into an isomeric crystalline lactone, (±)‐pyrocin. This is shown by oxidative degradation not to be a dihydrochrysanthemo‐lactone but to be (±)‐β‐isobutenylisohexano‐σ‐lactone. These lactones are substantially non‐toxic to houseflies.
Extraction of potassium from soil by electrodialysis and by ammonium acetate leaching. I.—soils from long‐term manurial trials
Authors: Cornfield A. H. , Pollard A. G. 
Published: November 2006

AbstractThe amounts of potassium extracted from soil by electrodialysis and by ammonium acetate leaching have been compared for soils taken from long‐term manurial trials.More potash was extracted, from soils receiving potash treatment, by electrodialysis in a Marsden cell than by ammonium acetate leaching; the difference increased as the dressing increased. With untreated soils slightly more potash was removed by ammonium acetate leaching than by electrodialysis. The non‐exchangeable potassium removed from soil by electrodialysis is probably derived from added and subsequently fixed potassium rather than from primary potassium‐bearing minerals.
Vegetable oils. I.—The component acids of Strophanthus sarmentosus seed oil
Authors: Gunstone F. D. 
Published: November 2006

AbstractThe component acids of Strophanthus sarmentosus seed oil have been determined by the modern methods of analysis. Major component acids are palmitic (11.9%), oleic (38.3%), and linoleic (29.8%) acids; the minor components include stearic acid (9.2%), some saturated acids (4.0%) higher than stearic, and an unsaturated hydroxy‐acid (6.6%) not previously reported.
The tuberculostatic action in vitro of the unsaponifiable fraction of cod‐liver oil
Authors: Emmerie A. , Engel Chr. , Klip W. 
Published: November 2006

AbstractFrom the unsaponifiable matter of cod‐liver oil a fraction has been isolated with strong inhibitory action upon the growth of Mycobacterium tuberculosis in vitro, using the fluid medium of Sauton with and without addition of serum albumin.The fraction was toxic to guinea pigs and therefore could not be studied effectively in experimental tuberculosis in these animals.
The decomposition of 2 : 4‐dichlorophenoxyacetic acid and 2‐methyl‐4‐chlorophenoxyacetic acid in the soil
Authors: Audus L. J. 
Published: November 2006

AbstractThe kinetics of the disappearance from garden loam of 2 : 4‐dichlorophenoxyacetic acid (2,4‐D) and 2‐methyl‐4‐chlorophenoxyacetic acid (MCPA) have been studied by a modification of the Lees & Quastel perfusion technique.Three phases in this disappearance can be distinguished: (a) an initial rapid adsorption on the soil colloids (2,4‐D : 0.17 mg./g. of soil; MCPA : 0.03 mg./g. of soil); (b) a lag phase during which no appreciable change in concentration of herbicide in the soil solution took place. The duration was approximately 14 days for 2,4‐D and 50–80 for MCPA; (c) a phase of rapid disappearance, which was maintained indefinitely on subsequent perfusions with fresh herbicide solutions. Maximum rate attained was of the order of 3 — 4 × 10−6 moles of 2,4‐D per g. of soil per day.These facts and results with a bacterial poison (sodium azide) suggest that the breakdown is due to a micro‐organism population proliferating in response to the perfusion.An organism (Bacterium globiforme) capable of decomposing 2,4‐D has been isolated from such soils but so far has not been grown in quantity in pure culture. ‘Cross perfusion’ experiments indicate that the same organism is responsible for breakdown of MCPA as well as of 2,4‐D but that a different enzyme system is involved in each case. The efficiencies of these systems are highest when acting on the ‘adapting’ molecule.Evidence has been obtained that 2 : 4‐dichlorophenol is an intermediate in 2,4‐D breakdown although the enzyme system taking part in the phenol breakdown seems to be easily poisoned by slight excess of substrate.
The free amino‐acids and peptides of plant tissues
Authors: Bathurst N. O. 
Published: November 2006

AbstractFree amino‐acids were extracted from pasture plants with 80% alcohol, and the residue was extracted with water to remove bound amino‐acids (peptide fraction). The alcohol extracts and the hydrolysed water‐extracts were assayed microbiologically for 17 amino‐acids. Total amino‐nitrogen was also estimated in these extracts by Van Slyke's nitrous acid method. Most of the free amino‐nitrogen was due to relatively few amino‐acids, chiefly the dicarboxylic acids (and their amides), alanine and serine. A larger number of amino‐acids contributed significantly to the peptide fraction. Treatment of the grasses with different nitrogenous fertilizers resulted in some differences in the amino‐acid patterns. Larger differences were noted between young and more mature tissues. Of the total amino‐nitrogen measured by Van Slyke's method about 70% in the free amino‐acid fraction and about 95% in the peptide fraction were accounted for by assay of individual amino‐acids.
Studies on egg shells. II.—A method for marking and counting pores
Authors: Tyler C. 
Published: November 2006

AbstractA method has been developed for marking the pores in egg shells by immersing them in concentrated nitric acid for very short periods of time. This makes the pores easily visible under the microscope, and counting can then be done by a statistical method. Not only is the total number of pores determined, but also a frequency distribution is obtained which indicates that the pores are not distributed at random.
Determination of nitrogen in soil and plant materials: Use of boric acid in the micro‐kjeldahl method
Authors: Yuen S. H. , Pollard A. G. 
Published: November 2006

AbstractThe use of boric acid for trapping ammonia in the micro‐Kjeldahl determination is examined. A suitable procedure, together with a modified type of micro‐distillation apparatus, is described.The buffer capacity of boric acid solutions was examined in relation to the sensitivity in the titration of ammonia dissolved in them. Two grades of boric acid, ‘pure’ (technical) and AnalaR, were compared; the former showed appreciable buffering on the acid side.The pH values of solutions of both grades decreased with increasing concentration. The sensitivity of the three indicators examined for the titration of ammonia diminished with increasing concentration of boric acid as a result of the increased buffering. With concentrated boric acid, all three indicators showed wide transitional periods at the end‐point, but in solutions of concentration up to 1‐0% of AnalaR grade the end‐points shown by all three indicators were sharp. The methylene blue‐methyl red indicator, however, was generally preferable.The ammonia‐fixing capacity of boric acid was studied in air‐bubbling tests and by recovery of a known amount of ammonia by distillation. A volume of 10 ml. of 1‐0% boric acid fixed 5 mg. of nitrogen as ammonia sufficiently firmly to afford accurate analyses. For macro‐determinations, 100 ml. of 2‐0% boric acid held firmly up to 90 mg. of nitrogen.
Analytical studies on the carbohydrates of grasses and clovers. IV.—further developments in the methods of estimation of mono‐, di‐ and oligo‐saccharides and fructosan
Authors: Wylam Clare B. 
Published: November 2006

AbstractMethods for the determination of the water‐soluble carbohydrates in both fresh and ensiled materials are discussed. A technique has been developed for the estimation of the oligosaccharides in grasses, after their separation from the other free sugars by paper chromatography. Their fructose content is determined by a colorimetric method, and fructose, glucose and galactose are estimated after their complete hydrolysis with 0.5N‐sulphuric acid.
The component fatty acids of bovine mammary‐gland fat
Authors: Garton G. A. 
Published: November 2006

AbstractThe component acids present in the fat of the secretory tissue of the udders of a lactating and a non‐lactating cow were determined. The fat of the lactating gland contained about half as much of the lower saturated acids (butyric‐capric) as a typical milk‐fat, with a compensating increase in the proportions of stearic and palmitic acid; all the minor un‐saturated acids of milk fat were detected. Although the fat of the non‐lactating gland contained small amounts of the minor saturated and unsaturated acids characteristic of milk fat, it differed from lactating‐gland fat and also from bovine depot‐fat in the relative amounts of the major component acids; palmitic acid comprised more than 40% of the total acids of this fat.
Determination of nitrogen in agricultural materials by the nessler reagent. II.—Micro‐determinations in Plant Tissue and in Soil Extracts
Authors: Yuen S. H. , Pollard A. G. 
Published: November 2006

AbstractThe total nitrogen content of plant tissue may be determined by direct nesslerization of sulphuric acid‐hydrogen peroxide digests with accuracy up to 5%. Similar application to soil extracts involves somewhat greater errors.In a spectrophotometric study of the Nessler colour, a filter showing maximum transmission at 420 mμ absorbs the greatest proportion of the colour.In the sulphuric acid‐hydrogen peroxide digestion of plant tissue, added ammonia is fully recovered but added nitrate suffers a loss of 24‐47%, the percentage loss decreasing as the amount of nitrate present increases.Bromothymol blue is a suitable internal indicator for the neutralization of test solutions before nesslerization. The blue colour of the indicator does not affect the absorptiometric measurement of the Nessler colour.Soil solutions and soil extracts may be decolorized satisfactorily by a specially treated activated charcoal. This charcoal does not absorb appreciable amounts of ammonia from soil extracts made with Morgan's reagent, 2.5% acetic acid or water. For more accurate determinations of ammonia in soil extracts etc., distillation of the ammonia into acid in the presence of bromothymol blue, followed by nesslerization, is preferable.
The seasonal variation in the combined L‐fucose content of the common British Laminariaceae and fucaceae
Authors: Black W. A. P. 
Published: November 2006

AbstractIn previous communications1‐3 the seasonal variation in the total ash, crude proteins, laminarin, mannitol, alginic acid, cellulose and iodine for the common British Laminariaceae and Fucaceae has been reported. The present article gives the seasonal variation for combined L‐fucose in the monthly samples collected during 1946.
The component acids and glycerides of areca‐nut (areca catechu) fat
Authors: Pathak S. P. , Mathur S. S. 
Published: November 2006

AbstractThe fatty acid composition of areca‐nut fat was determined by the usual ester‐fractionation method, using an electrically heated and packed column for fractional distillation under high vacuum (0.2 mm.). The glyceride structure was studied by crystallization of the neutral fat from acetone and ether; the composition of each of these glyceride fractions was studied by the fractionation method and the final possible glyceride composition computed therefrom. The chief component acids are lauric (19.5%), myristic (46.2%) and palmitic (12.7%), and in the unsaturated portion oleic (6.2%), linoleic (5.4%) and hexadecenoic acid (7.2%). Minor proportions of stearic, decanoic and of unsaturated monoethylenic C12 and C14 acids are also present. The chief component glycerides are (i) 56% of fully saturated (trimyristin, dimyristins and lauromyristopalmitin); (ii) 30% of mono‐unsaturated‐disaturated (mainly hexadecenolauromyristin, with some oleo‐(linoleo)myristopalmitins and dimyristins); (iii) 14% of diunsaturated‐monosaturated (oleolinoleoglycerides, mostly oleolinoleopalmitin). The glyceride composition follows closely Hilditch's rule of widest distribution of acyl radicals in the glyceride molecules. The fully saturated glyceride content of the fat, determined separately by the method of Hilditch & Lea,1 is 53.7%. The fully saturated components are found to contain (by the fractionation method) : 19.4% of lauric, 54.6% of myristic, 19.2% of palmitic and 6.8% of stearic acids. The proportions of various acids in the fully saturated components are similar to the corresponding ones in the saturated acid portion of the whole fat.
Allethrin
Authors: Elliott M. 
Published: November 2006

AbstractSynthetic work leading to the commercial preparation of allethrin (the ester of (±)‐cis‐trans‐3‐isobutenyl‐2 : 2‐dimethylcyclopropane‐1‐carboxylic acid [(±)‐cis‐trans‐chrys‐anthemic acid] with (±)‐2‐allyl‐3‐methylcyclopent‐2‐en‐4‐ol‐1‐one [(±)‐allethrolone]} is reviewed briefly. The relative insecticidal activity and abundance of the eight isomeric esters present in allethrin are deduced and the most effective is shown to be (+)‐allethronyl (+)‐trans‐chrysanthemate. The effect of various changes in the molecule of allethrin on insecticidal activity is described. The biological action of allethrin appears to be of a similar nature to that of the natural pyrethrins, and is associated with the particular stereochemical conformation in which the various parts of the molecule are held with respect to each other and with the chemical and physical properties of the groups so positioned. Although allethrin is inferior to the natural pyrethrins against most species of insects and by most methods of application, it is highly biologically active and, unlike many modern synthetic insecticides, has, so far, been found harmless to mammals.
Studies on egg shells. V.—Some physical and chemical characteristics of the egg shells of five different types of pheasant
Authors: Tyler C. , Geake F. H. 
Published: November 2006

AbstractA study has been made of a number of physical and chemical characteristics associated with five different types of pheasant‐egg shells. These include shell thickness, porosity coefficients, pore counts, membrane‐, pore‐ and matrix‐protein, calcium, carbonate, magnesium, phosphorus and citric acid. With most of these characteristics there were considerable variations between types, and, in particular, the wild type falls at one end or other of the range when the values are set out in order of magnitude. Certain relationships such as shell thickness: weight per unit area, shell weight: calcium content and calcium content: carbonate content were found, but some of these differed significantly from those found for hen‐egg shells.
The nature of bacterial lipids in the rumen of hay‐fed sheep
Authors: Garton G. A. , Oxford A. E. 
Published: November 2006

AbstractThe lipids extracted from the mixed ‘free’ rumen micro‐flora of two hay‐fed sheep consisted of 39.2% of phospholipids, 38.2% of neutral fat, 12.4% of lower fatty acids (probably rumen fermentation products), I0.I% of unsaponifiable matter and 0.I% of steam‐volatile, neutral solid. The ‘true’ lipids amounted to 9% of the dry weight of the bacteria. The neutral fat was noteworthy for the relatively high mean molecular weight (312‐0) of its component acids. No linoleic or linolenic acid was detected in the neutral fat or phospholipids. The significance of this with respect to the host animal is discussed. The N:P ratio of the phospholipids indicated the presence of mono‐ and di‐aminophosphatides. The unsaponifiable matter contained carotenoid pigments (probably xanthophylls) and 16.I% of a steroid‐like substance, possibly C27H48O2, m.p. 130–132°, precipitable by digitonin, but not identical with the hydrated form of cholesterol.
Studies on egg shells. VI. —The distribution of pores in egg shells
Authors: Tyler C. 
Published: November 2006

AbstractThe distribution of pores in egg shells has been studied by using a counting technique described in an earlier paper. The distribution is very different from the Poisson form, and different, but less so, form the negative binomial form. A new distribution, based on a modification of the Poisson form, has been developed, and this appears to fit the data quite well. The distribution is such as to give an arrangement of pores lying somewhere between randomness and complete uniformity, and a possible reason for this is discussed.
South african seaweeds: Seasonal variations in the chemical composition of some phaeophyceae
Authors: Von Holdt M. M. , Ligthelm S. P. , Nunn J. R. 
Published: November 2006

AbstractA study of the seasonal variations in the main constituents of Ecklonia maxima, Laminaria pallida and Bifurcaria brassicaeformis, which grow in abundance round the Cape Peninsula, has been made. Distinct variations were recorded for ash, alginic acid and mannitol, whereas laminarin, combined fucose and organic nitrogen showed only small changes.
The evaluation of whaling by‐products as feeding‐stuffs
Authors: Carpenter K. J. , Ellinger G. M. , Shrimpton D. H. 
Published: November 2006

AbstractVarious whale by‐products have been tested as protein supplements for young chicks. The meat meals were of a high value, having ‘gross protein values’ from 95 to 105% of that for the standard casein. Condensed whale solubles gave lower values (55–60%); this inferiority was reflected in their lower contents of lysine, cystine, methionine and tryptophan. The proximate analysis of these materials, together with the analytical results for the assay of riboflavin, pantothenic acid and for amino‐acids, are also reported.