Sorption-photometric and test determination of lead in environmental materials

The main analytical characteristics of the reaction of hexaoxacycloazochrom with lead were determined. A method for the sorption preconcentration of lead on the Thiopan 14 sorbent was proposed. Procedures were developed for the photometric determination of lead in natural waters, air, and soil at the level of the maximum permissible concentration. A new melange gel technique for preparing silicic acid xerogels modified with hexaoxacycloazochrom was developed for the test determination of lead in environmental samples at the level of the maximum permissible concentration.     

Certified reference material for the quality control of EDTA- and DTPA-extractable trace metal contents in calcareous soil (CRM 600)

Single extraction tests are commonly used to study the eco-toxicity and mobility of metals in soils, e.g. to assess the bioavailable metal fraction (and thus to estimate the related phyto-toxic and nutritional deficiency effects) and the environmentally accessible trace metals upon disposal of e.g. sediment on to a soil (e.g. contamination of ground waters). However, the lack of uniformity in the different procedures does not allow the results to be compared worldwide nor the procedures to be validated. This paper describes the interlaboratory testing of EDTA- and DTPA-extraction procedures for soil analysis, followed by the preparation of a calcareous soil reference material (CRM 600), the homogeneity and stability studies and the analytical work performed for the certification of the EDTA- and DTPA- extractable contents of some trace metals (following the standardized extraction procedures). Received: 21 May 1997 / Revised: 4 July 1997 / Accepted: 9 July 1997     

Radiochemical methods in nuclear waste management

Radiochemical techniques play an important role in nuclear waste management studies at the Centre for Analytical Research in the Environment. Current research includes the measurement of atmospheric emissions from a reprocessing plant, modelling of environmental pathways, and evaluation of reactor materials for the prediction of releases from ultimate disposal sites. A radiochemical separation procedure has been developed for¹²⁹I, which has been applied to a study of emissions from the Sellafield nuclear reprocessing plant. Atmospheric emissions, rainfall, grass, milk and wild food are analysed to model the ultimate fate of¹²⁹I. A new procedure has been developed for measuring sub-ppm concentrations of chlorine in archive steel samples as part of programme to produce an inventory of arisings of³⁶Cl from nuclear power stations. The method has been extended to other reactor materials and this paper describes the application of the radiochemical method for Magnox alloys, mild steel and cast iron.     

Hydrolysis of bis(chloromethyl)phosphonic acid p-nitroanilide in aqueous micellar surfactant solutions

The hydrolysis of bis(chloromethyl)phosphonic acid p-nitroanilide has been studied in the pH range 6.86–13.0 and the effects of ionic surfactant micelles on this process have also been examined. The nature of the micellar effects of cetyltrimethylammonium bromide (CTAB) and sodium dodecylsulfate (SDS) on this reaction lead us to conclude that both the neutral and anionic forms of the substrate are reactive, and that in the range of pH > pK_a hydrolysis of the ionic form of the anilide predominates, while at pH < pK_a the reaction of the neutral form is predominant. The binding constants for both the neutral and anionic forms of bis(chloromethyl)phosphonic acid p-nitroanilide in micellar CTAB and SDS solutions have been determined using a kinetic method, as well as by measuring the changes in the acid-base properties of the substrate resulting from the influence of micelles.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1718–1722, August, 1990.     

Trace aluminum determination and sampling problems of archeological bone employing destructive neutron activation analysis

A destructive neutron activation analysis procedure was developed for determining trace aluminum content in bone. It was found that soil contamination can influence the aluninum bone levels in prehistoric bone specimens. These maximum aluninum content values for prehistoric bone are larger than those of modern bone and comparable to aluminum levels present in bone from renal patients.     

Synthesis of 7-formyl-2-methyl-4-oxo-3,4-dihydropyrrolo[3,2-d]-pyrimidine and some other 7-substituted derivatives

A method that utilizes the Vilsmeier reaction to form a pyrrole ring was developed for the preparation of the previously unknown 7-formyl-2-methyl-4-oxo-3,4-dihydropyrrolo[3,2-d]pyrimidine from 2,6-dimethyl-5-amino-4-oxo-3,4-dihydropyrimidine. The nitrile, which was converted to the amide, was obtained from the oxime of the synthesized aldehyde. 7-Unsubstituted pyrrolopyrimidine was synthesized by oxidation of the aldehyde to the corresponding acid and subsequent decarboxylation. The IR and PMR spectroscopic data are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1672–1674, December, 1977.     

Use of the mannich reaction in the synthesis of bispidine

A three-step synthesis of bispidine ( 1 ) is described. Mannich condensation of N-benzyl-4-piperidone, formaldehyde, and benzylamine afforded N,N′-dibenzylbispidinone ( 5 ), which was reduced under modified Wolff-Kishner conditions to yield N,N′ -dibenzylbispidine ( 6 ). Catalytic debenzylation of this compound gave 1 .     

Recherches en série triazepine-1,2,4: 1 - détermination de la structure de la triazolotriazépinone obtenue par action de l'acétylacétate d'éthyle sur le diamino-3,4 triazole-1,2,4

The condensation of 3,4-diamino 1,2,4-triazole with ethyl aceloacelate gave 6-methyl-8,9-dihydro(7H)-s-triazolo[4,3-b]-1,2,4-triazepin-8-one ( 2 ); 2 has been caracterized by nmr spectroscopy and by comparison with its methylated derivative prepared in an unambigous manner.