Development of new dyes for use in integrated optical sensors

New chromoionophores have been developed, focused on NIR applications so that optode membranes may be used in monolithically integrated optical sensors. The wavelength of maximum absorbance has been estimated for a new model compound by the Pariser-Parr-Pople (PPP) method. Several cyanine type dyes have been tested as membrane chromoionophores. Membrane composition has been altered to overcome solubility problems. In this way, simple pH-sensitive optode membranes have been produced.     

Synthesis,characterization and properties of methylaminocellulose

Homogeneously prepared tosylcelluloses (TC) with degrees of substitution (DS) of DS_Tos 0.1–1.8 were used as intermediates for the synthesis of methylaminocelluloses (MAC) by nucleophilic substitution with methylamine. TC with DS_Tos up to 1.1 were shown to be valuable intermediates for selective synthesis of MAC with DS_MA varying from 0.1 to approximately 1. No nucleophilic substitution was observed at higher DS_Tos. At the chosen reaction conditions (60 °C, 48 h) residual tosyl moieties remained unchanged and little hydrolysis took place. The samples obtained were characterized by means of elemental analysis, FTIR and ¹³C CP/MAS NMR spectroscopy. ¹³C CP/MAS NMR spectroscopy was found to be an efficient tool for quantification of DS_MA. Furthermore, the swelling behaviour in water was investigated and preliminary tests concerning the bilirubin adsorption capacity of MAC were carried out.     

Darstellung und Molekülstrukturen von oligofunktionalen Dirheniumcarbonylderivaten aus Dirheniumnonacarbonylphosphan

Preparation and Molecular Structures of Oligofunctional Dirhenium Carbonyl Derivatives from Dirhenium Nonacarbonylphosphane Starting with dirheniumdecacarbonyl, one CO-Ligand was eliminated oxidatively and substituted by the labile acetonitrile ligand. As an intermediate eq-Re₂(CO)₉NCCH₃ was received. The reaction of this labilised carbonyl with tris(trimethylsilyl)phosphine and subsequent methanolysis gave ax-Re₂(CO)₉PH₃, which was isolated and characterized for the first time. Photochemical and thermal reaction of ax-Re₂(CO)₉PH₃ led to the new bi- and trinuclear complexes Re₂(μ-H)(μ₃-PHRe(CO)₅)(CO)₈, Re₂(μ-PH₂)₂(CO)₈ and Re₂(μ-H) · (μ-PH₂)(CO)₈, which were characterized by IR-, ¹H- and ³¹P-NMR spectroscopy. The structures of ax-Re₂(CO)₉PH₃, Re₂(μ-H)(μ₃-PHRe(CO)₅)(CO)₈ and Re₂(μ-PH₂)₂(CO)₈ were confirmed by single-crystal X-ray analysis. ax-Re₂(CO)₉PH₃ has a very short Re? P bond length of 228(2) pm.     

Editorial

The principles of quantum-mechanical measurements are a key issue in the foundation of modern physics. A beautiful consequence of these is the concept of Quantum Nondemolition (QND) measurements. Such measurements permit, in principle, to measure particular observables of a quantum system with unlimited precision, leaving their temporal evolution undisturbed. The application of QND measurements may play an important role in future high-sensivity experiments.Experimental QND measurements require appropriate measurements schemes and apparats, whose development took place in the past few years, thanks to strong progress in ultra-low noise mechanical, electronic and optical detection techniques, coherent light sources, and nonlinear optical systems. At present, interest is focused on measurements of mechanical observables, such as displacement of macroscopic masses and of intensity or phases of electomagnetic field modes in the optical spectral range.This special issue contains original papers on theory and experiments of QND measurements. Recent experimental developments are presented, and proposals and analyses of novel QND schemes are made.The issue focuses on contributions presented at the Workshop on QND Measurements, held March 27–29, 1996, on the Island of Reichenau, Lake Constance (Germany). The workshop was made possible through a generous grant from the Directorats General XII for Sciences, Research and Development of the European Commission.We thank Dr. W. Petrich for his help in preparing this special issue.     

Inclusive production of vector mesons in π+ p interactions at 250 GeV/c

We report on a study of ρ⁰, ρ⁺, ω, \(\bar K^{*0} (892)\) andK ^*0 (892) inclusive production in π⁺ p interactions at 250 GeV/c, for ρ⁺, \(\bar K^{*0} (892)\) for the first time in a π⁺ p experiment. The data are compared withK ⁺ p data in the same experiment, with results of other experiments and with quark-parton models. Interesting differences are found between ρ^+,0 and ω production.     

Multiplicity distributions at 250 GeV/c,a comparison of fits

The multiplicity distribution of all charged particles, as well as that of negatives and positives taken separately have been fitted by a number of recently proposed parametrizations. The negative binomial (2 parameters) and Laguerre distribution (3 parameters), in general, give good and very similar fits, but one of the parameters of the Laguerre distribution remains undetermined by the fit. The Krasznovszky-Wagner distribution (3 parameters) is better than the two first ones for full phase space, but slightly worse in intermediate rapidity intervals. Its disadvantage is the behaviour atn=0. The Branching distribution does not fit at an energy of \(\sqrt s = 22\) GeV.     

Forward-backward multiplicity correlations in σ+ p,K + p andpp collisions at 250 GeV/c

Forward-backward multiplicity correlations in σ⁺,K ⁺ p andpp collisions at 250 GeV/c ( \(\sqrt s \) =22 GeV) are given for all charges and for the different charge combinations. The correlations are found to be caused predominantly by centrally produced particles. It is demonstrated that this result is an agreement with observations at the ISR and the CERNp \(\bar p\) -Collider. The results are compared to expectations from LUND, DPM and FRITIOF Monte Carlo models and a geometrical picture relating correlations in hadron-hadron collisions toe ⁺ e ^? data in terms of impact parameters is tested.     

Die Mikrobestimmung der Fettsäuren im Blutserum

Analytical and Bioanalytical Chemistry -