Search results for "Iode"
showing 10 items of 1284 documents
Hydrogen sensor based on a palladium-coated fibre-taper with improved time-response
2006
Abstract We report an experimental study of the response of a hydrogen sensor, based on a palladium-coated tapered optical fibre, at different temperatures in the range −30 to 80 °C. We have studied the transmission, the time-response and the initial response velocity, being able to correlate these measurements with the pressure–composition isotherms of the Pd–H system and its phase transitions. Heating of the palladium layer optically with an auxiliary laser diode permits to improve the sensor's time-response at low temperatures.
The ability of soil-borne fungi to degrade organophosphonate carbon-to-phosphorus bonds
1997
The ability of a wide variety of soil-borne fungal strains to degrade four structurally different compounds containing P-C bonds, namely the naturally occurring amino acid ciliatine, the popular herbicide glyphosate, phosphonoacetic acid and 2-amino-3-phosphonopropionic acid, was studied in order to show that soil fungi may play an important role in the biodegradation of organophosphonates. Most of the strains appeared to utilize ciliatine as the sole source of phosphorus for growth. Only a limited number of strains were able to grow on the other phosphonates used in this work. The strains of Trichoderma harzianum, Scopulariopsis sp. and Aspergillus niger chosen for more detailed study show…
Selective Excitation of Guided Waves into Bone Phantoms by a Time-Delayed Laser Diode Array
2012
We excite selectively the Ao and So plate mode into an acrylic bone phantom using a laser diode array. This is done by controlling the time delay between the signals driving the array elements. Selective mode generation is important because it can potentially increase the sensitivity of in vivo osteoporosis screening.
Physicochemical characterisation of thermally aged anodic films on magnetron sputtered niobium
2010
The influence of thermal aging, at intermediate temperature (1h at 250°C) and in different environments, on the electronic and solid-state properties of stabilized 160 nm thick amorphous anodic niobia, grown on magnetron sputtered niobium metal, has been studied. A detailed physicochemical characterisation of the a-Nb2O5/0.5M H2SO4 electrolyte junction has been carried out by means of photocurrent and electrochemical impedance spectroscopy as well by differential admittance measurements. A change in the optical band gap (3.45 eV) of niobia film has been observed after aging (3.30 eV) at 250°C in air for 1 hour. A cathodic shift (0.15-0.2 Volt) in the flat band potential of the junction has …
SIMULTANEOUS DETERMINATION OF ATP, ITS METABOLITES AND NAD+ IN BLOOD BY HPLC WITH PHOTODIODE ARRAY DETECTOR
2013
SIMULTANEOUS DETERMINATION OF ATP, ITS METABOLITES AND NAD+ IN BLOOD BY HPLC WITH PHOTODIODE ARRAY DETECTOR Gueli Maria Concetta, Cusimano Vincenza, Lo Re Marianna, Giuseppe Salemi Dipartimento di Biomedicina Sperimentale e Neuroscienze Cliniche (BioNEC), Università degli Studi di Palermo. Nucleotides are major high-energy phosphate carriers, subunits of nucleic acids and precursors for the synthesis of nucleotide cofactors such as NAD+ and SAM. The study of purine nucleotides metabolism is very important topic for a right understanding for the cellular life. Living cells rely on ATP for growth, differentiation, and response to physiological stimuli and environmental stress. We propose a fa…
Optical, Structural and Paramagnetic Properties of Eu-Doped Ternary Sulfides ALnS2 (A = Na, K, Rb; Ln = La, Gd, Lu, Y)
2015
Eu-doped ternary sulfides of general formula ALnS2 (A = Na, K, Rb; Ln = La, Gd, Lu, Y) are presented as a novel interesting material family which may find usage as X-ray phosphors or solid state white light emitting diode (LED) lighting. Samples were synthesized in the form of transparent crystalline hexagonal platelets by chemical reaction under the flow of hydrogen sulfide. Their physical properties were investigated by means of X-ray diffraction, time-resolved photoluminescence spectroscopy, electron paramagnetic resonance, and X-ray excited fluorescence. Corresponding characteristics, including absorption, radioluminescence, photoluminescence excitation and emission spectra, and decay k…
Oligofluorene with multiple spiro-connections: its and their use in blue and white OLEDs
2019
Bond rotation within molecules is regarded as one of the nonradiative decay pathways and is detrimental to high photoluminescence quantum yields. In this work, a bulky and rigid blue emitter (Spiro-F) with five spiro-carbon linkages is synthesized. Spiro-F can serve not only as an active component of blue organic light-emitting diodes (OLEDs), but also as a host and blue emitter of white OLEDs. The WOLED offers a low turn-on voltage of 3.5 V and a high current efficiency of 3.6 cd A−1, together with CIE coordinates of (0.29, 0.33). This work proves the potential of super-rigid oligofluorene emitters for OLEDs.
Extended liquid-crystalline oligofluorenes with photo- and electroluminescence
2010
In this paper we report the synthesis and characterization of a series of low-molecular weight light-emitting molecules based on short oligofluorene cores, from one to three 9,9-dioctylfluorene units, elongated at the 2- and 7-positions by means of promesogenic units. The effect of this structural modification on the mesomorphic properties, as well as on the optical and electrochemical properties, is studied. The possibility of using these molecules as emitters in light-emitting diodes (LEDs) and polarized photoluminescent layers has been explored.
Efficient electroluminescence from a perylenediimide fluorophore obtained from a simple solution processed OLED
2009
Simple solution processed organic light emitting diodes are used to screen the performance of two types of highly efficient, narrow band red emitting fluorescent perylenediimides (PDIs). PDIs substituted at the diimide positions seem to form aggregates in the thin film architecture as evidenced by the shifted electroluminescent spectrum. When substituted on the bay position and when used both as the emitting and the electron transporting specie, bright electroluminescence with a narrow width around 610 nm reaching 500 cd m−2 at moderate voltages was observed, demonstrating the usefulness of these fluorophores for OLED applications.
Photoluminescent hybrid nanomaterials from modified halloysite nanotubes
2018
The synthesis of photoluminescent nanomaterials based on halloysite nanotubes is described. The obtained hybrid was characterized by means of TGA, FT-IR, DLS and XPS measurements; in addition its morphology was imaged by TEM and HR-TEM. The HNT hybrid also exhibited photoluminescent properties, both in solution and in the solid state, and white-light emission (0.24, 0.36; CIE coordinates) was observed. This work could be pioneering as a new strategy for manufacturing both LEDs and fluorescent tags based on HNT nanomaterials. © 2018 The Royal Society of Chemistry.