Determination of aromatic sulfonic acids in industrial waste water by ion-pair chromatography

A method for the identification and quantification of aromatic sulfonic acids in industrial waste water has been developed. The preparation of the samples comprises a clean-up step and an enrichment step, utilizing i) reversed-phase extraction and ii) ion-pair solid phase extraction. The aromatic sulfonic acids are separated by ion-pair chromatography with diode-array detection. An advantage of the developed ion-pair chromatographic method is the separation of linear alkylbenzenesulfonic acids (LAS), lignosulfonic acids and aromatic sulfonic acids in one chromatographic run. Also described is an optimized clean-up procedure for collected fractions of a preparative chromatographic run to identify monosulfonic acids with GC/MS after methylation. The detection limits for aromatic sulfonic acids in industrial waste waters are at the g/l level.     

Determination of a ternary mixture of penicillin-G sodium salt, penicillin-G procain salt and dihydrostreptomycin sulphate, by third-derivative spectrophotometry

Ternary mixtures of antibiotics, i.e. penicillin-G sodium salt, penicillin-G procain salt and dihydrostreptomycin sulphate salt, are assayed by 'zero-crossing' third-derivative spectrophotometry. Calibration plots follows Beer's law up to 40 mug/ml of penicillin-G sodium at 222.5 nm (r = 0.9997), 46 mug/ml of penicillin-G procain at 217 nm (r = 0.9999) and 36 mug/ml of dihydrostreptomycin sulphate at 211.5 nm (r = 0.9999), in the presence of one another. Detection limits at p = 0.05 level of significance were calculated to be, respectively, 0.66, 0.41 and 0.25 mug/ml. The procedure is rapid, simple, nondestructive and does not require solution of equations. The method was successfully applied for determining laboratory mixtures and commercial injections.     

Colorimetric method for determination of chlorine with 3,3',5,5'-tetramethylbenzidine

A new method is developed for the calorimetric determination in water of chlorine (free and combined) with 3,3′,5,5′-tetramethylbenzidine. The procedure proposed achieves a detection limit of 2 ng/ml and its sensitivity is greater than that of the methods used at present.     

On zeros of functions analytic in a half plane and completeness of systems of exponents

Sequences of zeros are described for functionsf, which, in the right half plane, are analytic and satisfy the condition ¦f(z)¦0(1) exp (¦z¦), 0<. A criterion of completeness of a system of exponents in a certain space of functions analytic in a half strip is established.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 46, No. 5, pp. 484–500, May, 1994.     

Inner Derivations and Primal Ideals of C*-Algebras

Let A be a C*-algebra. For a A let D(a, A) denote the innerderivation induced by a, regarded as a bounded operator on A,and let d(a, Z(A)) denote the distance of a from Z(A), the centreof A. Let K(A) be the smallest number in [0, ] such that d(a,Z(A)) K(A)||D(a, A)|| for all a A. It is shown that if A isnon-commutative and has an identity then either K(A) = , or K(A) = 1 / 3, or K(A) 1. Necessaryand sufficient conditions for these three possibilities aregiven in terms of the primitive and primal ideals of A. If Ais a quotient of an AW*-algebra then K(A) . Helly's Theorem is used to show that if A is aweakly central C*-algebra then K(A) 1.     

Magnetic field value in the weak energy release region of the solar corona

Spectrographic data from observations of the polarized weak steplike (with relatively sharp growth t 3 sec and slow decay t 10² sec) solar continuum radioemission are analyzed below. The main results are found using a sweeping spectrograph in the 8–12 GHz frequency range (sweep rate 1 sample per second and frequency resolution 120 MHz) and using the RT-22 radio telescope at the Crimean Astrophysical Observatory (angular resolution 4–6). In a series of events at the leading edge of the continuum a narrow-band frequency drifting emission termed blip-type is found. The degree of continuum circular polarization (p<10%) is low compared to that of the narrow-band component (p20%). Both components of the aforementioned events should be radiating on the second harmonic of the local plasma frequency in the context of a plasma generating mechanism. Based on the model proposed and using the observed degree of circular polarization of each component, we can estimate the strength of the magnetic field within the area of the source and the width of the angular spectrum from the radiating plasma turbulence. The results of analysis of the real microwave events are given below.Radiophysical Research Institute, Nizhnii Novgorod. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 37, No. 7, pp. 874–882, July, 1994.     

An investigation of intermittency in proton-gold, oxygen-gold, sulphur-gold and sulphur-sulphur interactions at 200 GeV per nucleon

The intermittency phenomenon is investigated in proton-gold, oxygen-gold, sulphur-gold and sulphur-sulphur collisions at 200 GeV per nucleon. The data were taken with the NA 35 streamer chamber detector at the CERN SPS. The data samples are carefully corrected for double counting of tracks and for contamination from photon conversions, particle decays and secondary interactions. The analysis is carried out in terms of factorial moments, using a new definition, and of correlation integrals. Both methods show the presence of nonstatistical fluctuations (intermittency). The main conclusions are: The observation of the effect for pairs of hadrons with negative charges and its near absence for pairs of opposite charges is consistent with the assumption that Bose-Einstein correlations yield the dominant contribution. The intermittency effect is not proportional to (dn/dy)^–1 which would be expected in superposition models. The measured relation between the second and third factorial moment for negative hadrons indicates that genuine 3-particle correlations are small. The predictions of a Monte Carlo simulation which is based on the Lund Fritiof model with the inclusion of Bose-Einstein correlations agree with the experimental results.Deceased     

μSR study of UTr2Si2, Tr=Co,Rh OR Pt

We have studied bySR spectroscopy the intermetallicsUTr ₂Si₂ where Tr=Co, Rh or Pt. Whereas for the Co compound we only get information on the muon localisation site, from the other two materials we obtain information on their electronic properties. We compare the characteristics of theirSR response.