Arens regularity ofK(X)

LetX be a reflexive Banach space andK(X) the operator algebra of compact linear operatorsu:XX. In this note we prove the following two results: a) Any decomposable bilinear operator fromK(X)×K(X) intoK(X) is Arens regular; b) ifX has an unconditional basis then any bounded bilinear operator fromK(X)×K(X) intoK(X) is Arens regular.     

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Path Integral Quantization of a Spinning Particle

Barut's classical model of the spinning particle having external dynamical variables x and p and internal dynamical variables and z is taken into account. The path integrations over holomorphic spinors and z are discussed. This quantization gives the kernel of the relativistic particles with higher spin as well as the Dirac electron. The Green's function of the spin-n/2 particle is obtained.     

Applications of the degree theorem to absolute continuity on Wiener space

Summary Let (,H, P) be an abstract Wiener space and define a shift on byT()=+F() whereF is anH-valued random variable. We study the absolute continuity of the measuresPºT ^–1and ( _F P)ºT ¹ with respect toP using the techniques of the degree theory of Wiener maps, where _F =det₂(1+F) × Exp{–F–1/2|F|²}.The work of the second author was supported by the fund for promotion of research at the Technion     

On Poisson brackets and symplectic structures for the classical and quantum zitterbewegung

The symplectic structures (brackets, Hamilton's equations, and Lagrange's equations) for the Dirac electron and its classical model have exactly the same form. We give explicitly the Poisson brackets in the dynamical variables (x ,p ,v ,S ^v). The only difference is in the normalization of the Dirac velocities =4 which has significant consequences.Dedicated to David Hestenes, whose work profoundly connects geometry (spacetime), algebra (Clifford), and physics (electron).     

Effects of carbodiimide structure on the immobilization of enzymes

A series of water-soluble disubstituted carbodiimides of different structure was tested for enzyme immobilization. In the experiments, a polyacrylamide-type bead polymer possessing carboxylic functional groups was used as support. The enzymes immobilized were aminoacylase (N-acylamino acid amidohydrolase; EC 3.5.1.14), arginase (L-arginine amidinohydrolase; EC 3.5.3.1), cyclodextrin glycosyltransferase (alpha-1,4-glucan 4-glycosyltransferase, cyclizing; EC 3.2.1.19), glucoamylase (1,4-alpha-D-glucan glycohydrolase, EC 3.2.1.3), and carboxypeptidase B (peptidyl-L-lysine [L-arginine] hydrolase; EC 3.4.17.2). It was found that the degree of immobilization strongly depended on the structure of carbodiimide used.     

A new (E,E)-dioxime and its mono and heterotrinuclear complexes containing an 18-membered dithiatetraazamacrocycle

The novel (E,E)-dioxime, 5,6:ll,12:17,18-tribenzo-2,3-bis(hydroxyimino)-7,16-dithia-9, 14-dioxo-l,4,10,13-tetraazacyclooctadecane (H₂L) has been synthesized by reacting (E,E)-dichloroglyoxime (2) with 2,3:8,9:14,15-tribenzo-4,13-di-thia-6,11-dioxa-l,7,10,16-tetraazahexzadecane (3), prepared by the reaction of N,N-bis(chloroacetyl)-1, 2-phenylene-diamine (1) with 2-aminothiophenol. Mononuclear complexes (4, 5) of this ligand have been synthesized by reacting the vic-dioxime (H₂L) with K₂PtCl₄ and NiCl₂ · 6H₂O, respectively. Heterotrinuclear complexes (6)and(7) have been prepared by the reaction of (4) and (5) mononuclear complexes with [Cu(MeCN)₄]PF₆. The structures of the vic-dioxime and its mono and trinuclear complexes were identified by elemental analysis, ¹H- and ¹³C-n.m.r, i.r. and m.s. data.     

The application of a double voltage modulation technique to a glow discharge source with a supplementary electrode

The Ar spectral lines are suppressed in glow discharge source atomic emission spectroscopy by a double voltage modulation technique with a supplementary electrode. The voltage is modulated between two levels, typically 350 and 700 V. At the lower voltage level mainly the Ar emission occurs where at the higher voltage level both the Ar and the metal atoms sputtered from the sample contribute to the emission. The power supply of the supplementary electrode is switched on when the glow discharge passes from operation at 700 V to 350 V. The intensity of argon gase lines is regulated by the current applied to the supplementary electrode at that period. Therefore, there is no need for electronical amplification and lower voltage adjustment of two operation modes. This modified DVM technique has been applied to the determination of Si and Cu in Al- samples. The suppression of Ar lines is possible, and the elements can be determined without Ar interferences.     

Stability constants of uranium(VI) and thorium(IV) complexes formed with 8-hydroxyquinoline and its 5-sulfonic acid derivative

In this study, the stability constants of uranium(VI) and thorium(IV) complexes formed with 8-hydroxyquinoline (8-HOQ) and its 5-sulfonic acid (8-HOQ-5-SO₃H) derivative have been determined using the Irving-Rossotti method, computing the Calvin-Bjerrum pH-titration data. As a result, it is determined that the thorium(IV) complexes are considerably more stable than the corresponding uranium(VI) complexes. On the other hand, the complexes formed between 8-HOQ-5-SO₃H and uranium(VI) or thorium(IV) are less stable than the corresponding 8-HOQ complexes.     

Colorimetric Sensing of the Insensitive Energetic Material 3-Nitro-1,2,4-triazol-5-one (NTO) Using l-Cysteine Stabilized Gold Nanoparticles and Copper(II)

Abstract

Since conventional sensitive explosives have given rise to unforeseen accidents during storage and transport, the demand of modern armies for insensitive energetic materials is on the rise. There are very few determination methods for the most widely used insensitive energetic materials such as 3-nitro-1,2,4-triazole-5-one (NTO). Thus, the aim of this work is the development of a rapid and practical nanoparticle-based colorimetric sensor for determination of NTO. The detection principle of the sensor involved electrostatic attraction of NTO anion to the ammonium group of l-cysteine functionalized gold nanoparticles (AuNP-Cys), followed by the formation of a Cu²⁺-coordination complex between particles to result in AuNPs agglomeration. The concomitant color change was from red to violet. The surface plasmon resonance band of AuNPs at 520?nm shifted to 650?nm upon chemical reaction and agglomeration. Spectroscopic evaluation was made by taking the ratio of 650?nm absorbance to that of 520?nm, and correlating this ratio to NTO concentration. The analytical performance characteristics of this ratiometric sensor for NTO as the molar absorptivity (ε); limits of detection (LOD) and quantification (LOQ) were: ε = (8.62?±?0.29) × 10³ L mol^?1 cm^?1, LOD = 0.25?mg L^?1, and LOQ = 0.85?mg L^?1. The sensor was applied to various energetic material mixtures containing 2,4,6-trinitrotoluene, hexahydro-1,3,5-trinitro-1,3,5-triazine, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, and tetryl. Additionally, the possible interference effects of commonly found soil ions such as Cl^–, NO₃^–, SO₄^2–, PO₄^3–, Mg²⁺, Ca²⁺, Na⁺, and K⁺ were studied. The proposed method was statistically validated against a literature liquid chromatography–tandem mass spectrometry (LC/MS-MS) method.