Search results for " Coating."
showing 10 items of 2558 documents
Comparative optical reflection and mass spectrometry analysis of thermodesorption of Langmuir-Blodgett films
1992
Abstract Thermodesorption of cadmium arachidate multilayers is studied by optical surface analysis and by mass spectrometry measurements. The optical reflection technique has been improved to discriminate signal contributions from desorption and light scattering. The scattering arises from film heterogeneities that are also observed by Nomarsky microscopy. The assessment of these heterogeneities is important to understand mass spectrometry data. Both the optical technique and mass spectrometry are sensitive to observing the multilayer phase transition at 110 °C and the desorption near 200 °C (at the heating rate applied). The mass spectrometry analysis yields detailed information on the des…
Fluorescence quenching by trapped charge carriers in N,N-dimethylaminobenzylidene 1,3-indandione films
2010
Effects caused by the applied voltage on the steady state and time-resolved fluorescence of vacuum evaporated N,N-dimethylaminobenzylidene 1,3-indandione films sandwiched between gold and aluminium electrodes were investigated and discussed. Fluorescence enhancement and quenching as well as the fluorescence band narrowing depending on the applied voltage have been observed. Fluorescence decay and recovery take place on a time scale of tens of seconds after voltage is switched on and off. Similar fluorescence decay also takes place after switching on the excitation light. These fluorescence changes are attributed to the exciton quenching by trapped charge carriers.
Binding isotope effects as a tool for distinguishing hydrophobic and hydrophilic binding sites of HIV-1 RT.
2014
The current treatment for HIV-1 infected patients consists of a cocktail of inhibitors, in an attempt to improve the potency of the drugs by adding the possible effects of each supplied compound. In this contribution, nine different inhibitors of HIV-1 RT, one of the three key proteins responsible for the virus replication, have been selected to develop and test a computational protocol that allows getting a deep insight into the inhibitors’ binding mechanism. The interaction between the inhibitors and the protein have been quantified by computing binding free energies through FEP calculations, while a more detailed characterization of the kind of inhibitor–protein interactions is based on …
Topologically Novel Multiple Rotaxanes and Catenanes Based on Tetraurea Calix[4]arenes
2006
Calix[4]arenes bearing at their wide rim four urea residues easily form hydrogen bonded dimeric capsules. This has been used to preorganise alkenyl functions attached to these urea groups for their controlled connection via metathesis reaction. Multimacrocyclic tetraurea derivatives are thus obtained in excellent yields via heterodimers which are formed exclusively with tetratosylurea derivatives. Heterodimerisation of such bis- and tetraloop tetraureas leads analogously to multicatenanes, or to rotaxanes by stoppering. Huge macrocycles are detached from tetraloop derivatives by cleavage of the urea function.
A heteropentanuclear oxalato-bridged [ReIV 4GdIII] complex: synthesis, crystal structure and magnetic properties
2012
The compound (NBu 4) 5[Gd III{Re IVBr 4(μ-ox)} 4(H 2O)]·H 2O (1), with intramolecular antiferromagnetic coupling, is the first Re(iv) system incorporating a 4f ion. © 2012 The Royal Society of Chemistry.
Chemically driven phase separation in black lipid membranes and its coupling to membrane functions
1992
Abstract We analysed the single-channel current fluctuations of gramicidin in bimolecular lipid membranes in order to demonstrate (i) the influence of protein binding to the lateral organisation of a mixed membrane, and (ii) how this couples to the function of the ionophore. Examples of phase separations induced by synthetic polyelectrolytes, as models for peripheral membrane proteins, and specific ligand-receptor interactions are presented and discussed in view of the important lateral order-function relationship in biomembranes.
[FeIILSCoIIILS]2⇔ [FeIIILSCoIIHS]2 photoinduced conversion in a cyanide-bridged heterobimetallic molecular square
2010
The self-assembly of [Fe(III){B(pz)(4)}(CN)(3)](-) and [Co(II)(bik)(2)(S)(2)](2+) affords the diamagnetic cyanide-bridged [Fe(II)(LS)Co(III)(LS)](2) molecular square which is converted into the corresponding magnetic [Fe(III)(LS)Co(II)(HS)](2) species under light irradiation at relatively low temperatures.
Synthesis and crystal structure of an unprecedented bismuth porphyrin containing ester pendant arms
2000
International audience; An easily prepared porphyrin with pendant arms is shown to form a stable complex with bismuth(III) ion; the complex is eight coordinate with a square antiprismatic coordination geometry; the solid-state structure exhibits the formation of a dimer assembled via mutual coordination of a terminal ester group.
Mixed micelles composed of Peptides and Gadolinium complexes as tumor-specific contrast agents in MRI: a SANS study
2004
A detailed structural investigation on mixed micelle aggregates as target-specific contrast agents for magnetic resonance imaging technique has been carried out by way of small angle neutron scattering measurements. These mixed micelles are formed by two new amphiphilic molecules formed by a bioactive peptide and a claw moiety. The first molecule, C18H37CONH(AdOO)(x)-G-CCK8 (C18LxCCK8, x = 2, 5), contains an 18-carbon-atom alkylic chain bound to the C-terminal of the cholecystokinin octapeptide amide (CCK 26-33 or CCK8) and is able to bind to the overexpressed CCK receptor of some tumor cells. The second molecule, C(18)H(37)CONHLys(DTPAGlu)CONH25- (C18DTPAGlu) or its gadolinium complex [C(1…
Determination of the electron-detachment energies of 2'-deoxyguanosine 5'-monophosphate anion: influence of the conformation.
2009
The vertical electron-detachment energies (VDEs) of the singly charged 2'-deoxyguanosine 5'-monophosphate anion (dGMP - ) are determined by using the multiconfigurational second-order perturbation CASPT2 method at the MP2 ground-state equilibrium geometry of relevant conformers. The origin of the unique low-energy band in the gas phase photoelectron spectrum of dGMP - , with maximum at around 5.05 eV, is unambiguously assigned to electron detachment from the highest occupied molecular orbital of π-character belonging to guanine fragment of a syn conformation. The presence of a short H-bond linking the 2-amino and phosphate groups, the guanine moiety acting as proton donor, is precisely resp…