1N Sodium Hydroxide Research Articles

Selective Extraction of Paraquat Using Sep-Pak C<SUB>18</SUB> Cartridge

Sep-Pak C18 cartridge was applied to selective extraction of paraquat from water, human urine, human blood, cow's milk and beverages. 1) Paraquat in distilled water was quantitatively retained on Sep-Pak C18 cartridge by adjusting the sample to pH 13, and quantitatively recovered by elution of 2 ml of 0.1N hydrochloric acid from the cartridge. 2) A sample (1-5ml) adjusted pH to 13 with 1N sodium hydroxide solution was injected into a Sep-Pak C18 cartridge, 3 ml of distilled water put into the cartridge to eliminate other components, and then 2 ml of 0.1N hydrochloric acid and 3×1 ml of distilled water were passed through the cartridge to elute paraquat. Prior to application to the cartridge, a blood sample was deproteinized with perchloric acid. The eluate was filled up to 5 ml with distilled water for determination of paraquat. No interferance was observed for colorimetric determination after reduction of paraquat in alkaline sodium dithionite solution. 3) Paraquat in spiked materials was quantitatively detected at the level of 10μg, and the minimum detectable amount of the herbicide was more or less 2μg with this method. As a pretreatment for analysis of drugs in biological samples by instrumental analyses such as gas chromatography, mass spectrometry and high performance liquid chromatography, Sep-Pak C18 is very useful for its cleanliness, simplicity, rapidity, efficiency and reproducibility.

Polysaccharides in fungi. IX. A .BETA.-d-glucan from alkaline extract of Dictyophora indusiata fisch.

A water-soluble β-D-glucan (T-5-N) has been isolated from 1N sodium hydroxide extract of the fruit bodies of Dictyophora indusiata FISCH. T-5-N, [α]18D+28.7°(c=0.5, H2O), IR νKBrmaxcm-1 : 890, was homogeneous as judged by ultracentrifugal analysis and Tiselius-type electrophoresis. Structural analyses indicated that T-5-N has a main chain composed of β-1→3 linked D-glucopyranosyl residues, and two single β-1→6 linked D-glucopyranosyl units are attached as side chains, on average, to every seventh sugar residue of the main chain. In addition, a few internal 1→6 linkages and branching points at position 2 of the β-1→3 linked main chain are also present in the molecule.

Colorimetric microdetermination of sulphites in foods by use of the modified rankine apparatus. IV.

Detection and determination of traces of sulphites in foods was attempted by use of the modified Rankine apparatus and pararosaniline colorimetry. Replacement of alkaline titration reported previously by pararosaniline colorimetry lowered the absolute detection limit from 30 μg (titration method) to 2 μg. In view of clean analysis, in the color developing system, 0.1 N-sodium hydroxide was used in place of mercuric chloride solution commonly used as an absorbant of sulphites. In order to prevent oxidative decomposition of sulphites during operation, nitrogen gas was used as carrier instead of air. Dimedone and sodium azide were used for the elimination of aldehydes and nitrites, respecitvely, in the sample, which will disturb the color development of sulphites with pararosaniline-formaldehyde reagents. With this improved method, it was possible to determine the residual sulphites in frozen peeled shrimps, sugared beans and other foods with low sulphite contents accurately.

Citrinin mycotoxicosis in the syrian hamster

Citrinin, dissolved in either a solution of equal parts of dimethylsulphoxide (DMSO) and 50% ethanol (EtOH) or 0.5 N-sodium hydroxide (NaOH), was administered by the ip or oral route to weanling Syrian hamsters. The single-dose ip LD 50 for citrinin dissolved in DMSO-50% EtOH, determined 72 hr after injection, was 66 mg/kg: for citrinin in 0-5 N-NaOH it was 75 mg/kg. The oral LD 50 for a single dose of citrinin dissolved in 0.5 N-NaOH was 220 mg/kg. The LD 50 values for seven daily doses of citrinin dissolved in 0.5 N-NaOH and given by the ip or oral route were 43 and 67 mg/kg/day respectively. Lesions in hamsters given single or multiple doses of citrinin were primarily found in the kidneys and included slight to marked necrosis of the renal cortical tubular epithelium, tubular calcification, the presence of protein and protein casts in the renal tubules and tubular dilation. The renal lesions in hamsters given multiple doses of citrinin were no more severe than those found in hamsters given only a single dose.

ChemInform Abstract: NOVEL SEMICONDUCTING ELECTRODES FOR THE PHOTOSENSITIZED ELECTROLYSIS OF WATER

AbstractDurch Aufsprühen entsprechender Elementchlorid‐Lösungen auf ein Ti‐Substrat und thermische Zersetzung der Chloride werden TiO2‐Alzüa‐ , TiO,‐SrO‐, TiOg ‐ Ga,O3‐, TiO,‐Eu,O3‐ und TiO2 ‐B,O3‐Elektroden hergestellt und ihre Eigenschaften bei der Verwendung als Photoanoden für die Wasserelektrolyse untersucht.

Novel Semiconducting Electrodes for the Photosensitized Electrolysis of Water

not Available.

US Geological Survey, Menlo Park, California, Radiocarbon Measurements I

A radiocarbon laboratory at the US Geological Survey Western Regional Headquarters in Menlo Park, California was established in temporary rooms in March, 1976. In August, 1976 the laboratory was dismantled and moved into a new building that was designed specifically for the facility. This list contains results of operations in the temporary laboratory, which was located in the basement of a two-story building. The counter shield was 15cm lead and 5cm borated paraffin with an additional 5cm of lead above the counters. The anticoincidence ring consisted of copper tubes, 5cm in diameter, mounted around a copper tube with an inside diameter of 15cm. Installed in the anticoincidence ring were the four sample counters, whose characteristics are shown in Table 1. The counting electronics unit, which is designed to service five sample counters, follows the design of Gulliksen (1972) in most respects. The sample counters were constructed of copper and quartz; their design is described in detail by Robinson (1977). The CO2 counting gas was purified by recirculation over copper and silver at ca 450°C. Wood samples were typically pretreated by leaching for 24 hours alternately in 1N sodium hydroxide and hydrochloric acid solutions at 70°C.

V-Triazolo[4,5-d]pyrimidines (8-azapurines). Part 19. Stability of N-alkyl-8-azapurines. Degradation by cold, dilute acid and base to N-alkyl-4-amino-1,2,3-triazole-5-carbaldehydes and -triazol-5-yl ketones

7-, 8-, and 9-Methyl and 8- and 9-benzyl derivatives of 8-azapurine (5) were hydrolysed by cold, aqueous N-hydrochloric acid to 1-, 2-, and 3-methyl and 2- and 3-benzyl (respectively) derivatives of 4-amino-1,2,3-triazole-5-carbaldehyde (6), mostly in high yield. Prior methylation in the 2-position prevented the hydrolysis. 6,9-Dimethyl-8-azapurine gave the analogous ketone (7a). Cold, aqueous N-sodium hydroxide behaved similarly expect that the presence of a 2-methyl group did not prevent reaction. From some of the alkaline hydrolyses, the same aldehydes (6) were isolated, as such or as their N-formyl or -acetyl derivatives which are intermediates, but in other cases self-condensation of the aldehyde occurred. Some of the 8-azapurines (5) were hydrolysed by simply boiling with water. 8-Azapurine disintegrated in acid but resisted alkali by forming an anion (Coulombic repulsion). These reactions, which have preparative value, were found by u.v. spectroscopy to show first-order behaviour. The half-lives of the starting materials were calculated. I.r and n.m.r. spectra and ionization constants are discussed.

モモ果実の品質保持に対する低温流通の効果

In our country white flesh peach fruits are mostly harvested at shipping maturity, i. e. initial stage of ripening, to protect from over-softening and bruising during distribution which is usually carried out at ambient room temperatures (25°C-30°C). 2-4 days are needed from producers to consummers. Recently there has been increased public interest in peaches harvested at the full ripe stage. The fruit is shipped at a low temperature in order to offer higher quality peaches to consummers.The present experiment was designed to simulate the conditions of transportation facilities for distribution. Peach fruit was held for 4 days after harvest at the room temperature of about 27°C or at 3°C. Their tastes were compared by 100 panel members and further quality changes were estimated by measuring total sugar, titratable acidity, ground color of peel and softening. Three cultivars belonging to fruits having white flesh, ‘Sunago’‘Hakuho’and‘Aichi Hakuto’were used in the experiment.1. When harvested at conventional shipping maturity and held at 3°C, there was no advantageous effect of low temperature on the taste of fruits.2. When harvested at full ripe stage and held at 3°C, sweetness was superior to the fruits harvested at shipping maturity and held at room temperature thereafter. At that time, the fruits at 3°C contained 8.8% total sugar and had 40ml of acid determined by titration with 0. 1N sodium hydroxide in 100ml juice, while the fruits held at room temperature displayed 8.3% and 55ml, respectively.3. The decreasing rates of sugar content during 4-day-holding in fruits held at room temperature and 3°C were 3.4% and 1.1%, respectively, and the decreasing rates of titratable acidity were 12.3% and 7.0%, respectively. The ground color of peel in the fruits at room temperature turned from light green to light yellow and fruit flesh softened to some extent during holding, while these changes in the fruits at 3°C were hardly detectable. It seemed therefore that the changes of ground color of peel and softening were strongly influenced by storage and shipping temperatures, but total sugar content and titratable acidity were hardly influenced at all.4. Total sugar content in peach fruits increased with the stage of ripening at harvest time, and then decreased at overripe or senescent stage. Titratable acidity decreased with the stage of ripening. The fruits softened characteristically, and the ground color of peel changed markedly from light yellow during ripening.In conclusion, the optimum time of harvest is the most important factor for distribution of peach fruit having good quality. This time is the full ripe stage of fruits for the case of short-haul transportation facilities as in our country when fruits are held at a low temperature.

Reactions of 2-, 6-, and 8-monosubstituted 1- and 3-methylpurines with hydroxide ions in water

The reactions of 2-, 6-, and 8-monochloro-(or methylthio-)1-(and 3-)methylpurines towards N-sodium hydroxide have been examined. 1-Methyl-2- and -6-methylthiopurine underwent normal nucleophilic displacement to give the hydroxypurines, but 1-methyl-8-methylthiopurine underwent ring fission to give 5-amino-2-methylthioimid-azole-4-carbaldehyde. 3-Methyl-6-methylthiopurine afforded 5-methylaminoimidazole-4-carbaldehyde predominantly, and some 6-hydroxy-3-methylpurine; and 3-methyl-8-methylthiopurine underwent ring opening like its 1-methyl isomer. 7-(and 9-)Methyl-2-methylthiopurines (for comparison) gave 4-amino-5-methyl-amino- and 5-amino-4-methylamino-2-methylthiopyrimidines, respectively. 6-Chloro-3-methylpurine gave 5-methylaminomidazole-4-carbonitrile and some 6-hydroxy-3-methylpurine; but 8-chloro-3-methylpurine was consumed without forming 8-hydroxy-3-methylpurine.

Aqueous Humor pH Changes After Experimental Alkali Burns

Following application of 2N sodium hydroxide, or 8.1N ammonium hydroxide to rabbit cornea, the aqueous humor pH reached a maximum of 10.2, 11.9, and 12 within six minutes following 20-, 50-, and 100-mu1 sodium hydroxide burns, respectively; after two hours the pH had fallen to 8.5, 10, and 10.5. The maximum rise following application of 100-mu1 of ammonium hydroxide was 10.8, declining to about 9 at two hours. The fall in pH following a 100-mu1 sodium hydroxide burn was not greatly influence by external lavage. However, the pH was significantly lowered (12 to 10) by paracentesis alone and further reduced by immediate or delayed intracameral administration of phosphate buffer. On the basis of these results moderately severe and severe alkali burns of the eye should be treated by paracentesis and if possible with anterior chamber reformation with a sterile solution.

The Fluorometric Determination of Cyclamate using 1, 2-Naphthoquinone-4-sulfonic Acid. II

Fluorometric determination of cyclohexylamine with 1, 2-naphthoquinone-4-sulfonic acid was applied to the determination of cyclamate in various foods. Cyclamate was hydrolyzed to cyclohexylamine as follows : To 1 ml of a sample solution containing 50-500μg of cyclamate, 0.5 ml of 0.5N sulfuric acid solution and 3 ml of dimethyl sulfoxide were added, heated for 2 hr in a boiling water bath, cooled, and diluted to 25 ml with water. Cyclohexylamine in the solution was estimated by the procedure described in the preceding paper. In the recovery test of cyclamate in various foods, the recovery was satisfactory. Determination of cyclohexylamine in human urine by the fluorometric method with 1, 2-naphthoquinone-4-sulfonic acid was also investigated. Cyclohexylamine was extracted with chloroform from urine basified with 2N sodium hydroxide. The reaction solution of cyclohexylamine and 1, 2-naphthoquinone-4-sulfonic acid was shaken with dichloromethane. The concentrated dichloromethane layer was spotted on a silicagel plate and developed with a mixture of ether : chloroform (1 : 2). Extract of the orange-yellow spot with borate buffer (pH 10.3) was treated with sodium borohydride, and acidified with 0.2 N sulfuric acid solution. The developed fluorescence was estimated. The recovery ratio was 94.3%.

Formation of Metallic Iron and Disproportionate Reaction of Iron (II)

A new reaction was carried out in a quasi-static way through an analytical filter paper (No.5 C) between 1 mol/l ferrous chloride and 1N sodium hydroxide solutions at room temperature for 24 hours. The reaction product of apparent density 3.15 g/cm3 was precipitated on the filter paper at the side of ferrous solution.It has been found that metallic iron was contained in the resultant product with ferrous hydroxide, green rust-I, magnetite and gethite. The metallic iron was identified by means of X-ray diffractometry, thermomagnetic analysis and chemical analysis. Needle-like metallic iron particles could be separated from resultant precipitate by dissolving in hydrochloric acid. By determination of consumed reagents due to the reaction in both solutions and of total iron contained in the resultant precipitate, it was proved that the reaction proceeded stoichiometrically.State analysis of iron was undertaken for obtaining the iron valences in the resultant precipitate. In spite of contamination of the solution with air during the reaction periods, the proportional relation between metallic (Fe0) and ferric (FeIII) iron could be observed. In proportion as these iron contents in the resultant preceipitate increased, the quantity of ferrous (FeII) iron decreased.It was considered from above experiments that the metallic iron was formed by the following disproportionate reaction of ferrous iron.3FeII Fe0 2FeIII

Reduction in Serum CO2 During Hyperalimentation

To the Editor.— Chan et al (220:1119, 1972) described the pH problem associated with administration of the hyperalimentation solutions. The first patient receiving hyperalimentation (750 ml of 5% dextrose-5% protein hydrolysate solution [C.P.H., Cutter Laboratories, Inc] with 350 ml of 50% dextrose in water [Cutter Laboratories, Inc]) at our institution exhibited progressively decreasing serum carbon dioxide concentrations. 1 The patient's serum carbon dioxide content was 30 mEq/liter at the time hyperalimentation was initiated. Over the next 12 days, the serum carbon dioxide progressively decreased to a nadir of 13 mEq/liter. It was thought that because the hyperalimentation solution had a high buffer capacity and a pH of 5.0 to 5.6 that it might have been depleting the body's buffer capacity. Therefore, the subsequent hyperalimentation solutions administered were adjusted to a pH of 7.0 with sterile 1N sodium hydroxide solution. Four days later the patient's carbon dioxide content had risen to

The Alkaline Hydrolysis of Some Lignin Model 2-Arylcoumarans

Reaction of the 2-arylcoumaran (2b) with 2b sodium hydroxide at 170� gave predominantly the (E)- and (2)-stilbenes (4a) and (5a) in the ratio 1 : 2, and the 2-arylbenzofuran (6) as a minor product. The isomeric 1,2-diarylpropan-1-ols (7b) and (8b) were prepared and gave on treatment with 2N sodium hydroxide at 170� an analogous mixture of stilbene isomers to that obtained from the coumaran (2b). The mechanism of formation of compounds (4a), (5a), and (6) is discussed.

Photometric determination of small amounts of copper in bismuth metal with diethyldithion-carbamic acid

Photometric determination of copper in bismuth with diethyldithiocarbamic acid has been presented. Copper and bismuth are extracted into organic solvent as carbamate complexes and bismuth chelate is easily backextracted into 2N sodium hydroxide solution, while copper chelate is not.One gram of bismuth metal was dissolved in nitric acid (1+1). The pH was adjusted to 89 with ammonis after adding 10 mlof 50% citric acid solution. It was transferred into a separatory funnel, and 1mlof 0.1% sodiumdiethyldithiocarbamate solution was added. The solution was shaken vigorously with 10ml of benzene for 3 min and the aqueous layer was discarded. Twenty ml of 2N sodium hydroxide solution was added into separatory funnel and the mixture was determined from the absorbance of the benzene layer at 435 nm.One hundred μg of each Ni, Co, Te and Pd in 1g of bismuth is not extracted as carbamate. However, in case of the presence of 0.1g of bismuth, a part of Ni, Co and Pd are extracted, and it was necessary to add EDTA for masking the reaction between these ions and carbamic acid. The limit of determination was 1μg.

Intramolecular electrocyclic reactions. Part II. Reactions of 1,5-di-phenylpenta-1,4-dien-3-one

An intramolecular electrocyclic reaction of 1,5-diphenylpenta-trans-1,trans-4-dien-3-one as the cation (generated with acetylium ions) affords, by conrotatory cyclisation, 2-acetoxy-trans-4,5-diphenylcyclopent-2-enyl sodium sulphate (XI), which is hydrolysed by hot 2N-sodium hydroxide or sodium carbonate solution with concomitant pinacolic change to 5-hydroxy-2,3-diphenylcyclopent-2-enone (X), sodium acetate, and sodium sulphite. Generation of the same cation with hydriodic acid gives, by conrotatory cyclisation and reduction, trans-3,4-di-phenylcyclopentanone (VII) in 13% yield.

ULTRAVIOLET SPECTROPHOTOMETRIC DETERMINATION OF PROTEIN IN SOME FOOD PRODUCTS

SUMMARY— The spectrophotometric method of estimating the protein content of whole milk at wavelength 280 nm (Nakai and Le, 1970) was modifed for corned beef, flour, bean and egg yolk. A clear solution was obtained by adding 50% sulfuric acid or 2N sodium hydroxide with and without 7–8M urea depending on solubility of the food products. The protein content was calculated from the absorbance at 280, 243 or 215 nm on o spectrophotometer. The correlation coefficient between the absorbance and the protein by Kjeldahl method was 0.99, 0.99, 0.99 and 0.99 with the coefficient of variability of Kjeldahl protein for absorbance of 1.8, 4.1, 3.8 and 4.1% for bean, corned beef, egg yolk and flour, respectively.

Disruption of Bacterial Protoplasts and Spheroplasts by Staphylococcal Delta Hemolysin

Fractionation of highly purified staphylococcal delta hemolysin by sucrose density gradient centrifugation, Sephadex G-150 and Bio-Gel A-5m gel filtration, carboxymethyl cellulose chromatography, and isoelectric focusing failed to separate the hemolytic, protoplast-lysing, and spheroplast-lysing activities of the preparation. The activities were reduced to a similar extent when delta hemolysin was treated with any of several phospholipids. The same was true when serum or proteolytic enzymes were used as inactivating agents. Cholesterol had no effect. The activities resisted heating at 80 C for 1 hr and were stable for at least 7 days at 5 C in 0.1 n sodium hydroxide, 0.1 n acetic acid, 6 m guanidine hydrochloride, 8 m urea, and 0.1% sodium lauryl sulfate.

Formation of 2-methylaminopyridine-3-carbaldehyde and the corresponding methylimine by ring-opening and ring-closing reactions of 3-cyano-1-methylpyridinium iodide in N-sodium hydroxide

Steam distillation of a solution of 3-cyano-1-methylpyridinium iodide in N-sodium hydroxide yields a mixture of 2-methylaminopyridine-3-carbaldehyde (I) and the corresponding methylimine (II). The formation of the former most probably proceeds via ring opening of the pseudo-base to give 2-formyl-5-methylaminopenta-2,4-dienenitrile (III)(or a tautomer). Ring closure of this intermediate should give 1,2-dihydro-2-imino-1-methyl-pyridine-3-carbaldehyde (IV), which under the reaction conditions would undergo the Dimroth rearrangement. Methylamine is also a reaction product, and could be formed by hydrolysis either of the intermediate (III) or of 2-methylaminomethylene-5-oxopent-3-enenitrile, the latter being formed by an initial attack at the 6-position. The methylimine (II) could be formed by the reaction of compound (I) with methylamine. Assignment of structure (I) is based on n.m.r. spectrometry and the fact that a Cannizzaro reaction yields an alcohol and a carboxylic acid, the latter giving 2-methylaminopyridine on decarboxylation. Further, the reaction of compound (I) with methyl iodide yields 3-formyl-1-methyl-2-methylaminopyridinium iodide, which on treatment with sodium hydroxide is converted into 1,2-dihydro-1-methyl-2-methyliminopyridine-3-carbaldehyde. Bromination and nitrosation of compound (I) yield 5-bromo-2-methylaminopyridine-3-carbaldehyde and 2-methyl(nitroso)-aminopyridine-3-carbaldehyde, respectively.