Liquid luminescence

Keywords Acidity Ionic liquids Luminescence Optical Spectroscopy... 

Margulis [34] has shown that the cavitation threshold may be confidently determined by the method of liquid sonoluminescence. Although the mechanism of liquid luminescence with cavity closing is not conclusively established—we do not know which factor is the main one in the luminescence in the moment ol collapse thermal phenomena, electric charges, or the superimposition of these processes—the method is of practical use for early observation of cavitation origination. 

Mudring, A.-V, Babai, A., Arenz, S., Giernoth, R., Binnemans, K., Driesen, K. and Nockemann, R, Strong luminescence of rare earth compounds in ionic liquids luminescent properties of lanthanide(III) iodides in the ionic liquid l-dodecyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, J. Alloys Compd. 418, 204-208 (2006). 

The scientific interests of Anatoly K. Babko ranged widely, especially in regard to fundamental aspects of analytical chemistry, applications of organic reagents in inorganic analysis, chemistry of complex compounds (including heteropolyacids), analytical applications of complex compounds in photometry, luminescence and chemiluminescence, ion chromatography, and liquid-liquid extraction. 

OXIDATIVE LUMINESCENCE OF UV ABSORBING CHEMICALS. APPLICATION TO THEIR DETERMINATION IN SUNSCREEN PRODUCTS BY REVERSED PHASE LIQUID CHROMATOGRAPHY WITH CHEMILUMINESCENCE... 

The aqueous micellai solutions of some surfactants exhibit the cloud point, or turbidity, phenomenon when the solution is heated or cooled above or below a certain temperature. Then the phase sepai ation into two isotropic liquid phases occurs a concentrated phase containing most of the surfactant and an aqueous phase containing a surfactant concentration close to the critical micellar concentration. The anionic surfactant solutions show this phenomenon in acid media without any temperature modifications. The aim of the present work is to explore the analytical possibilities of acid-induced cloud point extraction in the extraction and preconcentration of polycyclic ai omatic hydrocai bons (PAHs) from water solutions. The combination of extraction, preconcentration and luminescence detection of PAHs in one step under their trace determination in objects mentioned allows to exclude the use of lai ge volumes of expensive, high-purity and toxic organic solvents and replace the known time and solvent consuming procedures by more simple and convenient methods. 

Raw materials. Most luminous organisms can be stored at —70°C or below under aerobic conditions, or with dry ice, without a significant loss of luminescence activity for a period of several months or more, although a trial is always recommended. Even if a substance already extracted is unstable when stored with dry ice (like the luciferase of Cypridina and the luciferins of euphausiids and dinoflag-ellates), the same substance in the organisms before extraction can be safely stored at — 70° C or with dry ice. The material can also be stored with liquid nitrogen for added safety, but the quantity storable in a laboratory setup (e.g., Dewar flask) is limited. 

At this point, two options are available if required. (1) If more complete degassing is desired, freeze the liquid contents by soaking the appropriate part of reaction vessel in dry ice/acetone bath, evacuate to 10 pm Hg, then thaw the contents, followed by an additional 10 min degassing. (2) If the removal of residual 1602 is desired, mix the two solutions by tilting the vessel to consume the 1602 by luciferin-luciferase luminescence reaction. The resulting reaction will cease in 2-3 min. Then, degas the content for 1-2 min to remove the C02 produced in the luminescence reaction. 

Pringsheim, P. Vogel, M. Luminescence of Liquids and Solids Interscience ... 

Luminescence yields data that often cannot be provided by any other methodology. This book is a compilation of a wide variety of original research contributions. Substantial information is given on the use of luminescence techniques to understand specific cell responses and the chemical mechanisms of cell action. An examination of natural environments is presented in the form of specific studies that characterize materials in both solid and liquid form and give information on the respective reactions of these materials in soil and water systems. Advanced research on standardization and standards developed for luminescence studies, as well as both active and passive use of luminescence, is included. 

As indicated above in chiral mesophases, the introduction of a functional group in mesogenic stmctures offers the opportunity to achieve functional LCs. With this aim, mesomorphic crown-ether-isocyanide-gold(I) complexes (26) have been prepared recently [38]. The derivatives with one alkoxy chain show monotropic SmC mesophases at or close to room temperature. In contrast, the complexes with three alkoxy chains behave as monotropic (n = 4) or enantiotropic (n > 4) LCs. The structure of the mesophases could not be fully eluddated because X-ray diffraction studies in the mesophase were unsuccessful and mesophase characterization was made only on the basis of polarized optical microscopy. These complexes are luminescent not only in the solid state and in solution, but also in the mesophase and in the isotropic liquid state at moderate temperatures. The emission spectra of 26a with n=12 were... 

Besides this, the remarkable properties of gold(I) compounds, which often give rise to aurophilic interactions and/or to luminescence, are of interest when these properties are transported into the liquid crystal field. Although there is much still to be studied, it is already clear that luminescence can survive in the condensed but mobile state of a mesophase, and even in the isotropic liquid state of a molten gold compound. It also seems that aurophilicity can contribute in some cases to the formation of mesophases. 

Coco, S., Cordobilla, C., Dominguez, C. and Espinet, P. (2008) Luminescent gold(I) metallo-adds and their hydrogen bonded supramolecular liquid crystalline derivative s with decyloxystilbazole as hydrogen acceptor. Dalton Transactions, 48,6894—6900. 

Bayon, R., Coco, S. and Espinet, P. (2005) Gold Liquid Crystals Displaying Luminescence in the Mesophase and Short F... F Interactions in the Solid State. Chemistry - A European Journal, 11, 1079-1085. 

Coco, S., Cordovilla, C., Espinet, P., Martm-Alvarez, J. and Munoz, P. (2006) Dinudear gold(I) isocyanide complexes with luminescent properties, and displaying thermotropic liquid crystalline behavior. Inorganic Chemistry, 45, 10180-10187. 

Arias, J., Bardaji, M. and Espinet, P. (2008) Luminescence and Mesogenic Properties in Crown-Ether-Isocyanide or Carbene Gold(I) Complexes Luminescence in Solution, in the Solid, in the Mesophase, and in the Isotropic Liquid State. Inorganic Chemistry, 47, 3559-3567. 

Brinkman, U. A. Th., de Jong, G. J., and Gooijer, C., Use of luminescence techniques for sensitive and selective determinations in HPLC (high-performance liquid chromatography), Pure Appl. Chem., 59, 625, 1987. 

OTLC Open-tubular liquid chromatography PIL Plasma-induced luminescence... 

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