peu impor- tantes. La temperature ionique Ti et son evolution ont ete mesur6es par l spectroscopiquement. - 2e courbe : �volution de la temperature ionique Ti mesur6e spectroscopiquement.- 3e courbe of the confined energy is due to a temperature decrease. The cold plasma situated beyond the mirrors seems
E-print Network
(such as ion probe or laser ablation ICP-MS) are hampered by a lack of well characterized, homogeneous micro-analyses d'�l�ments en trace (par sonde ionique ou ICP-MS avec ablation laser) sont g�n�es par l during laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) and minor changes
mesurer 1'homogeneite du plasma (densite n, temperature T) et de faire des mesures de longueurs d sup6rieur a la temperature mesur6e par les sondes de Langmuir. L'etude de 1'evolution de 1'amplitude des modes qui peuvent interagir entre eux, mais aussi de faire des mesures de longueur d'onde et par
The properties of semi-insulating GaAs layers obtained by oxygen implantation were investigated. Each oxygen ion removes two carriers independently of the nature of the major impurity and the concentration of the substrates. Conditions for obtaining the l...
National Technical Information Service (NTIS)
constitue I'anode. Sur I'autre chariot mobile est montee une sonde electrostatique. -Fonctions deristiques de sondes electrostatiques presentant un courant electronique assez proche d'une fonction on consid6re la caracteristique de sonde electrostatique representant les variations du courant de sonde en
Uranium reacts with hydrogen to form a hydride: this reaction leads to the total destruction of the material. To modify the reactivity of an uranium surface towards hydrogen, ion implantation was selected, among surface treatments techniques. Four element...
The instrumentation allowing secondary ionic emission processing for the purpose of elementary and isotropic analysis is described. The device enables most of the analytical information contained in the tiny volume of matter sputtered during the impact of...
The investigation deals with a study of the properties of wave guides effected by ion exchange and double procedures in LiNbO3. It covers: The physical properties of the wave guides implemented by proton exchange, use of double procedures for manufacture ...
Use of ion implantation for modification of surface properties of materials by changing the mechanical and chemical behaviour of the surface layers is now the subject of growing research and application. This work deals with the influence of ion implantat...
A study was undertaken to show that a beam brightness can be improved by an order of magnitude when the sources of aberrations are suppressed in the anode region source, as well as in the extraction region and in the electrostatic focusing system. A calcu...
The ion flotation process for the recovery of cadmium from wet phosphoric acid (30%P2O5) has been studied. This technique combines a chemical recation between the collector and the cadmium to form a precipitate (sublate) which is carried to the surface of...
Molten salts are suitable solvents for biphasic catalysis: melting butyl-1 methyl-3 imidazolium chloride and aluminium chloride gives a polar and aprotic ionic liquid which is not miscible with hydrocarbons but dissolves organometallic complexes. Two type...
This work shows that if resonance ionization mass spectroscopy was first applied in isotopic separation, it's also an analyzing method adapted to the study of semi-conductor materials and thin foils. We have improved this technic: a neodymium laser couple...
A study was conducted to examine different possible designs for an ion source and accelerator assembly, suitable for operating in space. Such an assembly could serve to treat products in space such as the surfaces of space structures eroded by micrometeor...
The technique of nuclear microanalysis of deuterium by means of the reaction D (3He, p)4He was perfected on an ion implantor of 400 kV. The sensitivity of the method was about 10 to the 13th power deuterium atoms /sq cm, for an analytical depth of 5000 A ...
du platine. Les motifs lithograph14s sont constituds de lignes de I h quelques microns de largeur ou masque en platine avec lequel la s41ectivitd est au minimum 20 fois supdrieure h celle de la rdsine platine d'un diambtre de o,15 ~tm. L'dnergie ionique utilisde pour obtenir cette directivitd de gravure
A polyolefin surface becomes wettable when treated by micro-wave plasma or low-dose nitrogen ion implantation. X-ray photoelectron spectroscopy analyses, paramagnetic electronic resonance analyses, peroxide decomposition, wettability measurements, and inf...
Laser absorption spectroscopy is an appreciated diagnostic in plasma physics to measure atomic and ionic densities. We used it here more specifically on metallic plasmas. Firstly, a uranium plasma was created in a hollow cathode. 17 levels of U.I and U.II...
-391 THE DETERMINATION OF GRAIN BOUNDARY SEGREGATION PROFILES IN BORON CONTAINING AUSTENITIC STAINLESS STEELS USING TEM 96 Goteborg, Sweden R�sum� Mous avons utilis� simultan�ment la microscopie �lectronique par transmission, la microscopie ionique � effet de champ, la sonde atomique et la microscopie -� d�sorption pour
OF IRIDIUM FIELD EVAPORATION RATE A. MENAND and D. BLAVETTE U.A. CNRS, Laboratoire de Microscopie Ionique est interpret6 comme le resultat d'une desorbtion des ions iridium par un mecanisme d'effet tunnel en tunneling of W or B ions at low tempera- tures. We performed FIM experiments on Iridium to determine
The role of additional Heatings, such as the Ion Cyclotron Heating, is to raise magnetic fusion plasmas to higher temperatures, to satisfy the ignition condition. The understanding of the wave absorption mechanisms by the plasma first requires a precise d...
The glow discharge optical spectroscopy, is a well known technique. Its greatest difficulty consists in the definition of standards for surface analysis (for thicknesses below 1 micron). The aim of the present work is the manufacturing of standard samples...
La nitruration est un proc�d� thermochimique destin� � am�liorer les propri�t�s chimiques et m�caniques des aciers et des fontes. Les proc�d�s les plus courant sont la nitruration gazeuse, la nitruration en bain de sels et la nitruration ionique par plasma. Cette derni�re pr�sente certains avantages par rapport ...
NASA Astrophysics Data System (ADS)
Ionomer membranes, like Nafion^{tinytextregistered} used in fuel cell, present a nano- phase separation between domains with different ionic concentrations. Up to now models describe the ionic domains as spheres of about 40 � diameter. Small angles X-ray scattering studies over a large range of wave vectors, lead to a new assumption for the Nafion structure, describing the polymer aggregation as ...
... IMPROVEMENT OF THE MANE RADA 0 PArT 1 SYSTEM TNEENY, CALCULATINS, ANl PLAUININI [CUNCA MIID TITLE) ...
DTIC Science & Technology
An ionic pump has been devided thanks to au �liquid-liquid" extraction-reextration where the extraction compartment and the reextraction compartment are put in contact with one another through the membrane composed of an mediator diluted in the kerosene. We have applied this process to the system: uranyle nitrate, nitric acid-phosphate tributyle, kerosene-sodium carbonate. Interesting ...
In order to synthesize the superconducting phase La(sub 1.85)Sr(sub 0.15)CuO(sub 4) powders of La(sub 2)O(sub 3), CuO, and SrCO(sub 3) are usually ground together and annealed at high temperature. We studied another original way: the possibility of using ...
The fretting-corrosion behaviour of two tribological couples (TA6V/PMMA and 316L/PMMA) had been studied in order to better understand the degradation mechanisms observed on pivot prosthesis sealed in bones. Pressure appears to have a major role; at high c...
A study has been made of the initial stages of oxidation of yttrium ion implanted 304 steel in an attempt to shed some light on the so-called `reactive element effect' observed on chromia forming alloys. In situ XRD was used in order to observe the initial local structural changes during the high temperature oxidation process, while glancing angle XRD was used to monitor the longer range ...
Cette these est dediee a l'etude des materiaux InMnP et GaMnP fabriques par implantation ionique et recuit thermique. Plus precisement nous avons investigue la possibilite de former par implantation ionique des materiaux homogenes (alliages) de InMnP et GaMnP contenant de 1 a 5 % atomiques de Mn qui seraient en ...
Silica sodic solutions with molar ratio Rms [ SiO2] /[ Na2O] of 4.56 to 1 were obtained by depolymerisation of amorphous silical gel in sodium hydroxide. Solutions have been characterized by Qn distribution and infrared spectra. The decrease in degree of polymerization of the silicate anions shifts the (1000 1100 cm-1) Si-O-Si frequencies to lower frequency. The solution colloid- ionic evolution ...
Gombas. Resource and Job Monitoring in the Grid, Euro-Par 2003. [8] Rich Wolski, Neil T. Spring and Jim
... rept. Corporate Author : LABORATOIRE DE SPECTROMETRIE IONIQUE ET MOLECULAIRE VILLEURBANNE (FRANCE). ...
Matching the longitudinal beam emittance with separatrix acceptance in a ring accelerator has been considered. The aim of the matching is an intensity increase at the expense of the capture enhance and weakening of the Coulomb effect. Matching process par...
Work recently carried out established that very low concentrations of a substance (an impurity) can be detected in a solid solution by the analysis of the quadrupolar spectrum which characterizes the more abundant compound. It was shown that there is a relationship when the impurities are caused to appear in the matter by radiations of various types (for instance the gamma rays produced ...
Energy Citations Database
: We analyze the ion concentrations of groundwater issuing from deep wells located near the epicenter of the recent earthquake of magnitude 6:9 near Kobe, Japan, on January 17, 1995. These concentrations are well fitted by log-periodic modulations around a leading power law. The exponent (real and imaginary parts) is very close to those already found for the fits of precursory seismic activity for ...
We have performed thermal diffusion measurements of the molten mixture AgI/KI by a thermoelectric method in microgravity, these ones being disturbed on Earth by the free convection. These experiments have left unanswered questions and we have planned new measurements in space using an optical method, in order to check the hydrodynamical regime of the liquid during the diffusion. We have hence ...
L'etude de la stabilisation des poussieres de four a arc electrique (EAFD) par le laitier de haut-fourneau (GGBFS) et le ciment Portland (OPC) a ete realisee en trois parties. D'abord, la problematique de fixation du Cr dans les matrices cimentaires a ete etudiee en soumettant differents liants a des solutions de Cr lors d'essais de lixiviation en vrac et d'essais d'isothermes ...
The spiral structure of the cyanobacterium Arthrospira (Spirulina) platensis (Nordst.) Gomont was previously found to be altered by solar ultraviolet radiation (UVR, 280-400 nm). However, how photosynthetic active radiation (PAR, 400-700 nm) and UVR interact in regulating this morphological change remains unknown. Here, we show that the spiral structure of A. platensis ...
PubMed
We propose a theory of growth and form of hyphae in analogy with dendritic growth, the basic ingredients for the organization of the hyphal tip being the vesicles used for the growth and the proton pumps at the origin of membrane potential. The uniform growth may be unstable, favoring the formation of vesicle clusters separated with a characteristic distance essentially determined by the ...
The study presents a physical model and numerical simulation of an electromagnetic accelerator made of n fixed, coaxial coils, propelling a mobile coil. All the coils are assumed to be filiform loops. This formalism will make it possible to determine the ...
We begin this report by reviewing the theoretical foundations of a method to predict the amount of sound radiated by a baffled flat plate. The method uses measurement of the peripheral acceleration field to calculate the value of the sound. In the second ...
The conformation of a peptide, CterH, encompassing the last 56 C-terminal residues of Serratia marcescens haem acquisition protein HasA was examined by Circular Dichroism in amphipols solutions. The peptide, which contains the secretion signal of HasA, is unstructured in aqueous solution and adopts an helical structure upon the amphiphilic polymer addition. Furthermore, the helical content of ...
... 1 Jun 1991-31 May 1992. Corporate Author : LABORATOIRE DE SPECTROMETRIE IONIQUE ET MOLECULAIRE VILLEURBANNE (FRANCE). ...
Desk case will be opened for all inquiries. ln the event a question cannot be .... NSSC Monique Sullivan, l\\/ionique.Sullivan-1@nasa.gov, (228) 813-6134 ...
NASA Website
The first part of this report deals with a series of experiments carried out to find a suitable substitute for paraformaldehyde as a hardener in modified wattle-tannin based adhesives used in the manufacture of exterior grade particleboard. The second par...
of particles with Earthward propagating electromagnetic pulses of westward electric field and consistent propagating electromagnetic field pulse: par- ticles are energized via the betatron acceleration mechanism of the particle energy as it moves in the electromagnetic fields of the pulse is then given by [9]: dW dt = q
Energen, Inc. has designed, built, and demonstrated several fast and slow tuners based on its magnetostrictive actuators and stepper motor. These tuners are designed for Superconducting Radio Frequency (SRF) cavities, which are important structures in par...
Use of buncher in the external injection system of the isochronous cyclotron is intended to enlarge the luminosity, which is especially important during acceleration of very low-current beams of the polarized and multicharged ions. Problems of two-gap par...
The Accelerator cavities in this report can be modeled as a circuit with transmission line sections and lumped elements. Two configuration of the reduced length coaxial cavities are discussed; the folded cavity and the radial line loaded gap cavity are compared with design equations. The APS PAR 9.8 MHz first harmonic cavity is designed in the two ...
La photosensibilit� est un ph�nom�ne largement exploit� de nos jours dans les applications n�cessitant un changement d'indice de r�fraction permanent. Ce changement est observ� dans des fibres optiques ou des guides plans quand ils sont expos�s � la lumi�re ultraviolette. Plusieurs m�canismes seraient responsables de ce changement. Le mod�le qui revient le plus dans la ...
La photosensibilite est la propriete par laquelle une materiau donne voit son indice de refraction changer sous l'effet d'une exposition lumineuse. Malgre le nombre croissant de dispositif base sur ce phenomene, les mecanismes a la base de la photosensibilite sont encore debattus. Nous apportons dans cette these un eclairage original sur ce sujet en etudiant la matrice de ...
The primary nuclear reactions possibly occurring in accelerators operated on an energy level between 8 and 20 MeV are outlined, and their probability is estimated. Furthermore, the authors discuss which photoneutron rates par micron As are to be expected in case of different threshold energies in a tungsten sheet with a thickness of 6 mm and which ...
The + Gz acceleration of prolonged duration alters the sanguine outputs circulating in the various segments of the human body. The purpose of the study to evaluate the yield variations in the primary carotid artery under + Gz acceleration, which condition...
The magnetic moment, ?, of an electron in a h.f. plasma accelerator is evaluated in the case of negligeable axial acceleration in the resonance region (large injection velocity). D�tache au CEA Saclay par EURATOM.
This note details measurements of the APS positron linac klystron and accelerating structure gain and presents an analysis of the data using fits to simple mathematical models. The models are used to investigate the sensitivity of the energy dependence of the output positron beam to klystron parameters. The gain measurements are separated into two parts: first, the energy ...
DOE Information Bridge
The reaction of 1-n-butyl-3-methylimidazolium chloride (BMI.Cl) with sodium tetrafluoroborate or sodium hexafluorophosphate affords the molten salts BMI.X (1, X= BF4 and 2, X= PF6). Compounds 1 and 2 are viscous liquids within a wide range of temperature (down to 192 K). IR, NMR, density, viscosity and conductivity measurements suggest that compound 2 behaves quasi-molecular. Compound 1 is ...
This paper describes the proposed low-level rf system of the positron accumulator ring (PAR), the injector synchrotron, and the storage ring of the 7-GeV Advanced Photon Source. Four rf systems are described since the PAR consists of a fundamental frequency system at 9.8 MHz and a harmonic system at 117 MHz. A block diagram of an ...
For silica (pure and doped) optical fibers prepared from preforms irradiated by thermal neutrons and Ar^+ ions, the measurements of lifetime under transverse stress were carried out. It is found that the neutron bombardment leads to decrease of the lifetime and the strength of fiber while the ion implantation results in increasing of these parameters. The influence of particle irradiation on the ...
The Positron Accumulator Ring (PAR) is designed to accumulate and damp positrons from the 450-MeV linac during the 0.5-s cycle time of the injector synchrotron for the APS 7-GeV storage ring. During 0.4 s of each synchrotron cycle, up to 24 linac pulses are injected into the horizontal phase space of the PAR at a 60-Hz rate. Each injected pulse occupies ...
The author presents a parallelization of an accelerator physics application to simulate magnetic field in three dimensions. The problem involves the evaluation of high order derivatives with respect to two variables of a multivariate function. Automatic differentiation software had been used with some success, but the computation time was prohibitive. The implementation runs ...
Le nitrure de silicium est un materiau tres utilise en microelectronique et en optique integree due a l'excellente homogeneite et reproductibilite de son epaisseur et de son indice de refraction. De plus, l'indice de refraction eleve du nitrure de silicium est particulierement interessant pour les applications en biophotonique. En effet, ces dernieres annees les biocapteurs a champ evanescent ont ...
Voici une �tude des propri�t�s structurales et optiques de cristaux de GaAs semi-isolant implant�s � haute �nergie. Un �ventail de doses de 1012 � 1015 ions.cm-2 de Be � 2,3 MeV, de Si � 7 MeV et de Se � 10,9 MeV ont servi � produire des couches dop�es enfouies � plus de 3 m m sous la surface. Les �chantillons non recuits ont �t� analys�s pour en tirer le profil ...
Prior to the Voyager crossings of the termination shock, the explanation of anomalous cos-mic rays (ACRs) was thought to be well understood. The expectation was that as Voyager approached the shock, the energy spectra of ACRs would build up to that expected at the source, a power-law at low energies with a roll-off at higher energies. Instead, two components of ACRs were revealed in the crossings, ...
BACKGROUND & AIMS: The effects of trypsin on pancreatic ductal epithelial cells (PDEC) vary among species and depend on localization of proteinase-activated receptor-2 (PAR-2). Bicarbonate secretion is similar in human and guinea pig PDEC; we compared its localization in these cell types and isolated guinea pig ducts to study the effects of trypsin and a ...
The Annex to the 7-GeV Advanced Photon Source Conceptual Design Report updates the Conceptual Design Report of 1987 (CDR-87) to include the results of further optimization and changes of the design during the past year. The design changes can be summarized as affecting three areas: the accelerator system, conventional facilities, and experimental systems. Most of the changes ...
The nitriding kinetics and the mechanical properties of nitrided cast alloys are studied on graphite spheroidal and gray casts. Nitriding was performed in a standard nitrogen-hydrogen gas mixture. The results show that the hardening of the diffusion zone ...
Ionic nitriding was studied. The diffusion layers were quantitatively and microstructurally analyzed. The fundamental mechanisms which govern the in situ transformation of sulfur carbides into nitrides and lead to the precipitation of cementite lattices a...
This theoretical and at the same time experimental study was carried out at the 'Service Ionique Generale' in Grenoble. High frequency wave generators are already in use there, making it possible to approach the fusion conditions of light elements such as...
The first paper looks at the peculiarities involved in wetting thin fibers due to their curved surfaces. Macroscopic wetting films can be stabilized by external interactions like magnetic ones for ferrofluids. If thin enough, microscopic films are stabili...
Hydrochemical evaluation of groundwater systems can be carried out using conventional and multivariate techniques, namely cluster, factor analyses and others such as correspondence analysis. The main objective of this study is to investigate the groundwater quality in the Blue Nile basin of eastern Sudan, and to workout a hydrochemical evaluation for the aquifer system. Conventional methods and ...
Vortices pinning in supraconductors In this article we report on the investigation of the dynamics of vortices based on the high frequency linear response. We present a serie of measurements of the complex penetration depth in the mixed state in a variety of samples, including conventional materials (Nb, V, PbIn), the non-conventional heavy fermion UPt3, and the high-T_c cuprate YBaCuO. We have ...
A fraction of the material sputtered from a sample by an ion beam is collected in a tantalum cell brought at a high temperature where it is thermalized and partly ionized. Ions are extracted from the cell and analyzed in a mass spectrometer. A method based on this principle was proposed a few years ago for the analysis of thin layers. Here we are using the same device for studying the surface ...
The Procedure Execution Manager (PEM) combines a complete scripting environment for coding accelerator operation procedures with a manager application for executing and monitoring of the procedures. PEM is based on Tcl/Tk, a supporting graphics library, and the dp-tcl extension for distributed processing. A careful design balance has been achieved which meets the flexibility ...
A 9.8-MHz RF accelerating cavity is developed for the first harmonic system in the APS PAR and an aluminum unit is tested. The design goal si 40 kV at the accelerating gap, Q-factor of {approximately} 7,000 for the accelerating mode, 1.2-m diameter, 1.6-m length with good mechanical strength and stability. The ...
The rate at which X-ray structures of membrane proteins are solved is on a par with that of soluble proteins in the late 1970s. There are still many obstacles facing the membrane protein structural community. Recently, there have been several technical achievements in the field that have started to dramatically accelerate structural studies. Here, we ...
The growth rate of Brillouin instability in a subdense plasma is calculated for high power laser flux (but less than the field corresponding to that of laser wave propagation in the relativistic state). The anti-Stokes component is shown to be ignorable. ...
The asymptotic behavior of the Brillouin instability is studied. In regimes where the instability is of a convective nature, the growth of a perturbation is finite in the case of a plasma of finite length. The reflectivity depends on the level of thermal ...
We describe the rf system of the positron accumulator ring (PAR) of the 7-GeV Advanced Photon Source. Two rf systems are described: a fundamental frequency system at 9.8 MHz, and a twelfth harmonic system at 117.3 MHz. A block diagram of an accelerating unit is shown and descriptions of various amplifier subsystems are given (including amplifier design, ...
The parvulin family of peptidyl-prolyl cis/trans isomerases (PPIases) catalyzes the cis/trans isomerization of the peptide bonds preceding Pro residues. Eukaryotic parvulin-type PPIases have been shown to be involved in cell proliferation and cell cycle progression. Here we present the biochemical and molecular characterization of a novel multi-domain parvulin-type PPIase from the human pathogenic ...
Les piles � combustible alcalines sont des syst�mes performants qui fonctionnent � temp�rature ambiante et n�cessitent moins de m�taux pr�cieux (platine) que les piles � combustible � membrane protonique (PEMFC). Des �tudes approfondies concernant la synth�se de membranes alcalines � base d'oxyde de poly�thyl�ne (PEO) ou d'Epichlorhydrine (EpCI) ont montr� que ces ...
The paper begins with a short review on the theory of the surface dielectric response function of optical phonons in thin films, which is an important quantity for the understanding of various surface phenomena. The dielectric response of surface phonons to infra-red excitations is analysed with some details for two test cases: a SiO2(0001) self-supported film and NaCl(001) slabs on a thick Ge ...
The effects of +Gz acceleration (head to feet of the pilot) were investigated in relation to the constraints created by modern combat aircraft. The carotid artery cross section and the blood flow were measured by echotomography and echo Doppler measuremen...
[...]Decomposition and Multigrid Algorithms for the Calculation of Compressible Flows Abstract : This thesis deals with non-overlapping domain decomposition algorithms for the resolution of the Euler and Navier-Stokes equations. A backward Euler discretisation [...
[...]SCOLE (beam+antenna) introduced by the engineers of NASA. We considered the case where the acceleration term [...]poutre+antenne) introduit par les ing�nieurs de la NASA. Nous avons consid�r� le cas o� le terme [...
Various theories of bremsstrahlung radiation are critically compared. Experimental data on the production of gamma radiation by relativistic electron beams are compared to the theoretical results, in order to estimate the validity of the various theories. (auth)
A bremsstrahlung beam produced by electrons from a Van de Graaff accelerator has been used to excite fifteen levels in 59Co up to about 4.5 MeV. The first five of these have energies (keV), spins and par The first five of these have energies (keV), spins ...
A general study is made of the optical elements of a double-fccusing magnetic sector by the fringe effect, with a view to its application to the monochromation of the proton, deuteron, or triton beam of the 1.4 Mev accelerator. (auth)
finding of acceleration in African infants living in poverty with poor nutrition, sanitation, and medical advice about infant motor development. At what age should children master a par- ticular motor skill multiple times under the respective regions in the legend. Most studies focused on infants and children
The existence Rayleigh-Taylor instabilities, in laser heated plasmas, is shown. By means of the acceleration of flat three-layered Au-Al-Au targets, a mixing zone, under the concept of Rayteigh-Taylor instabilities, is observed. The Al emission spectra is...
Under heavy loads, flow accelerates the degradative effect of creep fatigue on carbon-epoxy laminates (+ or - 45 degrees)2S. Under light loads (which are normally encountered), flow decreases the degradative effect. In combined fatigue, a linear model of ...
The paper describes the first experimental method which has fixed the relative value of the X-ray loss by electron back scattering. Measurements were performed, using gold, copper and aluminium specimens and accelerating voltages from 10 to 30 kV. The exp...
The use of transcranial Doppler monitoring is recommended for detecting acceleration induced loss of consciousness (LOC). One transcranial Doppler pulse device was developed specifically to function in a centrifuge and another for use in a Mirage 2000, ca...
In this document the authors summarize the following: (1) an overview of basic concepts of ultrahigh vacuum needed for the APS project, (2) a description of vacuum design and calculations for major parts of APS, including linac, linac waveguide, low energy undulator test line, positron accumulator ring (PAR), booster synchrotron ring, storage ring, and insertion devices, and ...
La synthese et la caracterisation de derives regioreguliers du polythiophene ont ete effectuees en solution et sur des films minces. La spectroscopie UV-visible de ces derives a permis de constater qu'ils peuvent posseder des proprietes chromiques particulieres selon le stimulus auquel ils sont soumis. Par exemple, une augmentation de la temperature permet en effet aux ...
