Zum Nachweis von Phenol im Harn

Ohne Zusammenfassung     

Zur Bestimmung von Ozon neben Chlor Und Untersalpeters?ure

Ohne Zusammenfassung     

A nanostructured hybrid material based on polymer infiltrated porous silicon layer

In this work, we report on the fabrication of an hybrid material based on a porous silicon (PSi) layer infiltrated by an amino functionalized poly(ε-caprolattone) (PCL-NH₂). The organic–inorganic structure has been characterized by variable angle spectroscopic ellipsometry, optical reflectometry and water contact angle measurements. A polymer coated PSi layer, 3 μm thick, shows improved wettability and chemical stability against long lasting, up to 18 min, exposure to an alkaline environment. Even after basic treatment, the structure still retains a very good quality optical response, so that it may be proposed as a high performance platform for biochemical sensing applications.     

Doppler-free saturated-absorption spectroscopy of CO2 at 4.3 microm by means of a distributed feedback quantum cascade laser

We report the application of a cw distributed feedback quantum cascade laser to Lamb-dip spectroscopy of CO2 at 4.3 microm. With the laser operating in the free-running mode, we observed the sub-Doppler profile of the P(28) line of the (0,1(1),0)->(0,1(1),1) hot band by implementing a pump-probe scheme and using wavelength modulation spectroscopy for highly sensitive detection of saturated absorption signals. We investigated the main limitations to the observation of a narrow resonance, with particular attention to the effect of the laser current noise. We determined the intrinsic laser emission width, which was found to be approximately 3.4 MHz (FWHM) for an observation time of approximately 200 ms.     

Heliotropium bacciferum Forssk. (Boraginaceae) extracts: chemical constituents,antioxidant activity and cytotoxic effect in human cancer cell lines

Heliotropium bacciferum (Boraginaceae) is a perennial herb, growing in the Bechar region of Algeria, where it is traditionally used for skin diseases and tonsillitis. Herein, we report the isolation and characterization of sixteen secondary metabolites from the aerial part extracts. They include a sterol (1), megastigman type nor-isoprenoids (2, 3, 4, 6, 8, 10), C-11 terpene lactones (5 and 9), and a monoterpene (7) from the chloroform extract (HB-C); monoterpene glucoside (14), and phenolic compounds (11–13, 15, 16) from the methanol one (HB-M). Their structures were elucidated by spectroscopic methods including 1D and 2D NMR experiments, and ESIMS analysis. HB-M showed a significant and concentration dependent scavenging activity in vitro against the radicals DPPH and ABTS, related to the phenol derivatives (11–13, and 15–16), and HB-C inhibited the growth of colon cancer cell lines, mainly for the presence of the antiproliferative C-11 terpene lactones (5 and 9).     

1,3-dimethylimidazolium-2-carboxylate: the unexpected synthesis of an ionic liquid precursor and carbene-CO2 adduct

1,3-Dimethylimidazolium-2-carboxylate is formed in good yield, rather than the anticipated organic salt, 1,3-dimethylimidazolium methyl carbonate, as the reaction product resulting from both N-alkylation and C-carboxylation of 1-methylimidazole with dimethyl carbonate; the crystal structure of the zwitterion exhibits pi-stacked rings and two-dimensional sheets constructed by hydrogen-bonds from imidazolium-ring hydrogens to the carboxylate group.     

Disulfides by reduction of thiosulfunic S-esters

Disulfides are smoothly prepared from thiosulfonic S-esters by chlorotrimethylsilane and sodium iodide. In addition, thiosulfonic S-esters have been shown to be probable intermediates in other already known reactions leading to disulfides.     

External proficiency testing exercises on human leukocyte antigen typing in Italy between 1998 and 2002

External proficiency testing exercises are essential tools for measuring the quality of different kinds of performances related to health care and to ensure that they are uniform throughout a region. For many years, the Italian National Transplant Centre and the Italian National Institute of Health have been organizing external proficiency testing exercises for serological and genomic human leukocyte antigen (HLA) typing, following the rules of the European Federation of Immunogenetics. This society provides accreditation for immunogenetical tests to those European countries which want to collaborate on programmes on solid organ and bone marrow transplantation. The results of the Italian external proficiency testing exercises are very satisfactory because of the progressive improvement of the quality of HLA typing seen in Italian laboratories between 1998 and 2002. The attained outcome will certainly guarantee a more reliable service in clinical practice, and will contribute to the process of approaching the highest quality in health care.     

On the local analysis of continuum deformation

Summary The role of the cartesian representation of the deformation gradient in the non-linear theory of continuum deformation is studied. Indeed, explicit formulae for the local analysis of deformation are obtained in terms of such a representation. Further, some connections with the multiplicative strain and rotation measures are examined.

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Sommario Si studia il ruolo della rappresentazione cartesiana del gradiente di deformazione nella teoria non-lineare della deformazione di un corpo continua tridimensionale. In termini di tale rappresentazione, si ottengono formule esplicite per le variazioni locali di lunghezza, angolo, area e volume. Si esaminano inoltre alcune connessioni con le misure multiplicative di deformazione pura e di rotazione.