Lajos Sarka、László Burai、E. Brücher2000-02-18Chemistry - A European Journal
The kinetic stability of the complex [Gd(DTPA)]2- (H5DTPA = diethylenetriamine-N,N,N',N",N"-pentaacetic acid), used as a contrast-enhancing agent in magnetic resonance imaging (MRI), is characterised by the rates of the exchange reactions that take place with the endogenous ions Cu2+ and Zn2+. The reactions predominan…
Advanced MRI Techniques and ApplicationsLanthanide and Transition Metal ComplexesMRI in cancer diagnosis
Carlos M. Nuñez、Bor‐Sen Chiou、Anthony L. Andrady 等 4 位作者2000-02-18Macromolecules
The rheological properties of different generations of hyperbranched polyesters in 1-methyl-2-pyrrolidinone solvent and their blends with a poly(2-hydroxyethyl methacrylate) are examined in this study. All the hyperbranched polyester solutions exhibit Newtonian behavior, with steady shear viscosities independent of sh…
Advanced Polymer Synthesis and CharacterizationSynthetic Organic Chemistry MethodsDendrimers and Hyperbranched Polymers
Reiko Azumi、Günther Götz、Tony Debaerdemaeker 等 4 位作者2000-02-18Chemistry - A European Journal
The molecular arrangements of three different alkyl-substituted oligothiophenes both in two-dimensional adsorbed layers at a substrate interface and in bulk three-dimensional crystals were studied. Scanning tunneling microscopy (STM) was used to investigate the ordering of the conjugated oligomers in two-dimensional l…
Machine Learning in Materials ScienceVarious Chemistry Research Topics
A. Henglein2000-02-18The Journal of Physical Chemistry B
Bimetallic gold and platinum particles of the Pt−Au and Au−Pt core−shell type are prepared using hydrogen reduction and radiolysis techniques. The optical absorption spectra are recorded and compared to various Au−Pt particles described in the literature. Au core Pt shell particles catalyze the hydrogen reduction of s…
Gold and Silver Nanoparticles Synthesis and ApplicationsElectrochemical Analysis and ApplicationsLaser-Ablation Synthesis of Nanoparticles
U. Michelsen、Christopher A. Hunter2000-02-18Angewandte Chemie International Edition
Control over self-assembling polymers is characterized by size-exclusion chromatography: The polymer, formed from cobalt porphyrins functionalized with two pyridine ligands, organizes to a high molecular mass (>100 kDa) in solution (see scheme). The mean molecular mass can be precisely controlled by adding monofunctio…
Molecular Sensors and Ion DetectionSupramolecular Chemistry and ComplexesPorphyrin and Phthalocyanine Chemistry
Silvio Aime、Mauro Botta、Eliana Gianolio 等 4 位作者2000-02-18Angewandte Chemie International Edition
Different relaxation rates of water protons are enhanced by a contrast agent for magnetic resonance imaging (MRI). A supramolecular adduct of poly-β-cyclodextrin and [(MnII(tpps)]4− is described. Oxidation of the manganese center to MnIII causes a marked decrease in the observed relaxivity r1p (see scheme), which make…
Advanced MRI Techniques and ApplicationsLanthanide and Transition Metal ComplexesElectron Spin Resonance Studies
Takeshi Serizawa、Kenichi Hamada、Tatsuki Kitayama 等 6 位作者2000-02-18Journal of the American Chemical Society
Isotactic (it-) and syndiotactic (st-) poly(methyl methacrylate)s (PMMAs) were synthesized by anionic polymerization in toluene at −78 °C with t -C 4 H 9 MgBr and t -C 4 H 9 Li/(C 2 H 5 ) 3 Al, respectively, as initiators. Polymers were assembled by the stepwise immersion of a 9-MHz quartz-crystal microbalance (QCM) a…
Polymer Surface Interaction StudiesMolecular Junctions and NanostructuresAcoustic Wave Resonator Technologies
Dirk Volkmer、Alexander Du Chesne、Dirk G. Kurth 等 7 位作者2000-02-18Journal of the American Chemical Society
We describe the spontaneous self-assembly and the superstructure of a discrete surfactant-encapsulated cluster, (DODA) 40 (NH 4 ) 2 [(H 2 O) n ⊂Mo 132 O 372 (CH 3 COO) 30 (H 2 O) 72 ] ( 2, n ≈ 50), which consists of a hollow giant isopolyoxomolybdate core covered by a hydrophobic shell of dimethyldioctadecylammonium (…
Metal-Organic Frameworks: Synthesis and ApplicationsPolyoxometalates: Synthesis and ApplicationsNanocluster Synthesis and Applications
C. Caccamo、Giuseppe Pellicane、Dino Costa2000-02-17Journal of Physics Condensed Matter
Thermodynamically self-consistent integral equation theories (TC-IETs) supplemented by a one-phase freezing criterion, and Monte Carlo simulations, are used to investigate the thermodynamic and structural properties, as well as the phase diagram, of the hard-core Yukawa fluid (HCYF). The attention is focused on rapidl…
Phase Equilibria and ThermodynamicsMaterial Dynamics and PropertiesSpectroscopy and Quantum Chemical Studies
А. В. Федоров、S. Brazovskiǐ、V. N. Muthukumar 等 10 位作者2000-02-17Journal of Physics Condensed Matter
We present the first direct observation of temperature-dependent Fermi wave vectors in the quasi-one-dimensional conductor K 0.3 MoO 3 . By monitoring the position of these vectors through the Peierls transition using angle-resolved photoemission spectroscopy, we demonstrate that the temperature dependence of the char…
Physics of Superconductivity and MagnetismOrganic and Molecular Conductors ResearchElectronic and Structural Properties of Oxides
H. Eugene Stanley、Sergey V. Buldyrev、Osamu Mishima 等 6 位作者2000-02-17Journal of Physics Condensed Matter
Although H 2 O has been the focus of a considerable amount of research since the beginning of the century, its peculiar physical properties are still not well understood. First we discuss some of the anomalies of this `complex fluid'. Then we describe a qualitative interpretation in terms of percolation concepts. Fina…
Phase Equilibria and ThermodynamicsMaterial Dynamics and PropertiesTheoretical and Computational Physics
R. Böhmer、G. Hinze、T Jörg 等 5 位作者2000-02-17Journal of Physics Condensed Matter
2 H NMR experiments in deuterated supercooled liquids are discussed in relation with α- and β-relaxation heterogeneity with particular emphasis on the latter. The results are exemplified using data from deuterated ortho -terphenyl, propylene carbonate and toluene where partial deuteration provides additional informati…
Material Dynamics and PropertiesGlass properties and applicationsThermodynamic properties of mixtures
Jun Zhang、Qiwei Yan、Fangwei Wang 等 5 位作者2000-02-17Journal of Physics Condensed Matter
The magnetic and transport properties of layered manganese oxides La 1.2 Sr 1.8 Mn 2 - x T x O 7 (T = Fe, Co, Cr) are reported. The undoped oxide La 1.2 Sr 1.8 Mn 2 O 7 is ferromagnetic (FM) below 125 K where an insulating-metallic (I-M) transition occurs. Fe and Co doping have similar effects on the properties of La…
Magnetic and transport properties of perovskites and related materialsRare-earth and actinide compoundsAdvanced Condensed Matter Physics
Jyongsik Jang、Joon Hak Oh、Sung In Moon2000-02-17Macromolecules
The effects of terminal groups and composition of hyperbranched polymers (HBPs) on the crystallization behavior of poly(ethylene terephthalate) (PET) in HBP/PET blends were investigated using in situ FT-IR spectroscopy and differential scanning calorimetry. Hyperbranched aliphatic polyester was synthesized from an AB…
Polymer crystallization and propertiesDendrimers and Hyperbranched PolymersSynthesis and properties of polymers
Amit M. Kulkarni、Avik P. Chatterjee、Kenneth S. Schweizer 等 4 位作者2000-02-17Journal of Physics Condensed Matter
The strength of depletion interactions has been characterized by measuring the second virial coefficient, B 2 , of suspensions of lysozyme molecules in the presence of non-adsorbing polymer poly(ethylene glycol) (PEG). The solution properties of the PEG are characterized for three molecular weights (1000, 6000 and 12…
Phase Equilibria and ThermodynamicsMaterial Dynamics and PropertiesEnzyme Structure and Function
Jean‐François Joanny、Martin Castelnovo、Roland R. Netz2000-02-17Journal of Physics Condensed Matter
We review some of the theoretical results that we have obtained recently on the adsorption of polyelectrolytes on surfaces of opposite charge. We consider two problems, the formation of polyelectrolyte multilayers and the formation of complexes between rigid polyelectrolytes and small spheres. For polyelectrolyte mult…
Polymer Surface Interaction StudiesForce Microscopy Techniques and ApplicationsElectrostatics and Colloid Interactions
Paul D. Bartlett2000-02-17Journal of Physics Condensed Matter
The phase behaviour of a polydisperse mixture of hard spheres is examined within a moment-density approximation. The role of size fractionation and the difference between quenched and annealed phase behaviour is outlined. The quenched phase diagram shows a terminal level of polydispersity above which no fluid-crystal…
Phase Equilibria and ThermodynamicsMaterial Dynamics and PropertiesAdvanced Thermodynamics and Statistical Mechanics
Alexander K. Hipp、Bernhard Walker、Marco Mazzotti 等 4 位作者2000-02-17Industrial & Engineering Chemistry Research
The possibility of using acoustic spectroscopy for the on-line and in-situ monitoring of particle size distributions and volume concentrations in batch crystallization processes is investigated. First, the acoustic technique is discussed, along with the evaluation of the involved model parameters. Second, for a seeded…
Crystallization and Solubility StudiesChemical and Physical Properties in Aqueous SolutionsElectrostatics and Colloid Interactions
Haythem A. Saadeh、Liming Wang、Luping Yu2000-02-17Macromolecules
The Stille coupling reaction was explored to synthesize novel polymers with a pending NLO chromophore exhibiting a large μβ value but high chemical sensitivity. This approach enabled the synthesis of aromatic polyimides through the careful design of dibromo monomers bearing NLO chromophores. The resulting polyimide wa…
Nonlinear Optical Materials ResearchAcoustic Wave Resonator TechnologiesSynthesis and properties of polymers
Clemens Bechinger、Qi‐Huo Wei、P. Leǐderer2000-02-17Journal of Physics Condensed Matter
When a two-dimensional colloidal suspension of highly charged particles is subjected to a periodic one-dimensional (1D) light field, a liquid-solid transition can be induced. This phase transition is well known as light-induced freezing. However, upon further increase of the intensity, the crystal is found to remelt (…
Material Dynamics and PropertiesSpectroscopy and Quantum Chemical StudiesElectrostatics and Colloid Interactions