Yan Wang、Ya Chen、Colleen Lavin 等 4 位作者2000-04-01Journal of Phycology
Extracellular matrix (ECM) polymers secreted by the diatoms Achnanthes longipes Ag. and Cymbella cistula (Ehr.) Kirchn. completely encase the cell and are responsible for adhesion and other interactions with the external environment. To preserve details of the highly hydrophilic ECM in the native state and to preserve…
Marine and coastal ecosystemsMicrobial Community Ecology and PhysiologyDiatoms and Algae Research
Waldemar Ziomek、Marek Reformat、E. Kuffel2000-04-01IEEE Transactions on Dielectrics and Electrical Insulation
A computerized pattern recognition system based on the analysis of phase resolved partial discharge (PRPD) measurements, and utilizing genetic algorithms, is presented. The recognition system was trained to distinguish between basic types of defects appearing in gas-insulated system (GIS), such as voids in spacers, mo…
High voltage insulation and dielectric phenomenaPower Transformer Diagnostics and InsulationGeophysical Methods and Applications
H. J. Bray、Simon A. T. Redfern2000-04-01Mineralogical Magazine
Abstract The dehydroxylation of Ca-, K-, Mg- and Na-saturated Wyoming montmorillonite has been studied by thermogravimetry (TG), infrared (IR) spectroscopy and X-ray diffraction (XRD). Samples saturated with either Ca 2+ or Mg 2+ show a predominantly diffusion-controlled reaction step, whereas Wyoming montmorillonite…
Concrete and Cement Materials ResearchClay minerals and soil interactionsLayered Double Hydroxides Synthesis and Applications
G. Reginato、Lorenzo Di Bari、Piero Salvadori 等 4 位作者2000-04-01European Journal of Organic Chemistry
A new series of porphyrins has been synthesised, incorporating four identical chiral binaphthyl derivatives in the meso-positions. Owing to a hindered rotation around the bond between the naphthyl and the porphyrin, four atropisomers are generated, which were fully separated by preparative TLC and thoroughly character…
Porphyrin and Phthalocyanine ChemistryMetal-Catalyzed Oxygenation MechanismsAxial and Atropisomeric Chirality Synthesis
Hans Wong、Timo Meyer‐Friedrichsen、Tony Farrell 等 5 位作者2000-04-01European Journal of Inorganic Chemistry
In order to investigate nonlinear optical properties, in particular second harmonic generation (SHG) of organometallic complexes, numerous dipolar monocationic sesquifulvalene complexes of the general form [Mc–Z–C7H6]+ have been synthesised (Mc = metallocenyl), wherein the metallocenyl moiety Mc acts as an electron do…
Porphyrin and Phthalocyanine ChemistryNonlinear Optical Materials ResearchPhotochemistry and Electron Transfer Studies
D. Kilian、D. Knawby、M. A. Athanassopoulou 等 7 位作者2000-04-01Liquid Crystals
Two liquid crystalline vanadyl complexes have been studied by frequency domain dielectric spectroscopy over the range 10 mHz to 13 MHz. The materials exhibit two or three columnar phases denoted Colro, Colrd, and Colhd that were identified by X-ray diffraction. In the higher temperature Colrd phase, a relaxation proce…
Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsMolecular spectroscopy and chirality
Shadpour Mallakpour、Abdol‐Reza Hajipour、Sepideh Khoee2000-04-01Journal of Polymer Science Part A Polymer Chemistry
A new facile and rapid polycondensation reaction of 4,4′-(hexafluoroisopropylidene)-N,N′-bis(phthaloyl-L-leucine) diacid chloride (1) with several aromatic diamines, including benzidine (2a), 4,4′-diaminodiphenyl methane (2b), 1,5-diaminoanthraquinone (2c), 4,4′-sulfonyldianiline (2d), 3,3′-diaminobenzophenone (2e), P…
Multicomponent Synthesis of HeterocyclesSynthesis and properties of polymersMicrowave-Assisted Synthesis and Applications
Joachim Kusz、H. Spiering、Philipp Gütlich2000-04-01Journal of Applied Crystallography
Iron(II) complexes exhibiting thermal spin crossover may be converted from the 1 A 1 low-spin (LS) state to the 5 T 2 high-spin (HS) state by irradiation with green light (light-induced excited spin-state trapping, LIESST). The lifetime of the metastable LIESST state may be sufficiently long for X-ray diffraction stud…
Magnetism in coordination complexesHemoglobin structure and functionElectron Spin Resonance Studies
Stephen F. Swallen、Zhengguo Zhu、Jeffrey S. Moore 等 4 位作者2000-04-01The Journal of Physical Chemistry B
Steady-state and time-resolved fluorescence data are used to examine the photophysical characteristics of a series of phenylacetylene dendrimers. Correlated excimer formation is observed in some solvents which is found to depend strongly upon initial excited-state placement within the dendrimer framework. The results…
Gold and Silver Nanoparticles Synthesis and ApplicationsLuminescence and Fluorescent MaterialsDendrimers and Hyperbranched Polymers
Michael Stockenhuber、Michael J. Hudson、Richard W. Joyner2000-04-01The Journal of Physical Chemistry B
A new preparation method for highly dispersed iron in mesoporous MCM-41 materials has been developed, employing a methanolic solution of iron(III) nitrate. In situ EXAFS and NO adsorption followed by IR spectroscopy suggest that the resulting iron is present mainly in the form of isolated cations bound to the internal…
Catalytic Processes in Materials ScienceZeolite Catalysis and SynthesisMesoporous Materials and Catalysis
M. Hennion、F. Moussa、G. Biotteau 等 6 位作者2000-04-01Physical review. B, Condensed matter
Elastic and inelastic neutron-scattering experiments have been performed in a ${\mathrm{La}}_{0.94}{\mathrm{Sr}}_{0.06}{\mathrm{MnO}}_{3}$ untwinned crystal, which exhibits an antiferromagnetic canted magnetic structure with ferromagnetic layers. The elastic small q scattering exhibits a modulation with an anisotropic…
Magnetic and transport properties of perovskites and related materialsRare-earth and actinide compoundsAdvanced Condensed Matter Physics
Michael Breulmann、Sean A. Davis、Stephen Mann 等 5 位作者2000-04-01Advanced Materials
3D inorganic monoliths with sponge-like texture have been produced using polymer–gel templates. Colloidal suspensions of magnetite or titanium dioxide nanoparticles were diffused into swellable gels (see Figure) composed of acrylic acid–based copolymers, and possessing 3D channels. Hybrid composites were produced that…
Bone Tissue Engineering MaterialsMesoporous Materials and CatalysisAerogels and thermal insulation
Lin Xiu-hua、Jiang Bingxi2000-04-01Chinese Physics
Seven absorption group-bands (1D2, 1G4, 3F2, 3F3, 3H4, 3H5, 3F4) of Tm3+ in YVO4 single crystals have been observed in the orientation absorption spectra recorded in the spectral range from 200 to 4000 nm at 300K. The integrated absorption cross section for each group-band was accurately evaluated. On the assumption t…
Luminescence Properties of Advanced MaterialsGlass properties and applicationsSolid State Laser Technologies
Yongfeng Lu、H. Q. Ni、Zhong Ren 等 9 位作者2000-04-01Journal of Laser Applications
Zinc oxide thin films have been grown on silicon (100) and sapphire (0001) substrates by pulsed laser deposition. The thin films deposited at different processing parameters were evaluated by x-ray diffraction, Raman spectroscopy, and atomic force microscopy (AFM). The influences of substrate temperature and laser flu…
ZnO doping and propertiesGaN-based semiconductor devices and materialsGa2O3 and related materials
Kyung Bin Joo、J. Paitz、Detlef Klimm 等 6 位作者2000-04-01Crystal Research and Technology
Barium cerate crystals of 1.5 mm diameter could be grown from melt solutions containing barium chloride, barium oxide (from thermolysis of barium carbonate), and cerium(IV) oxide. The maximum size of the crystals is limited by the low solubility of cerium(IV) oxide in the barium chloride melt (ca. 0.1 Mol%). The flux…
Microwave Dielectric Ceramics SynthesisNuclear materials and radiation effectsElectronic and Structural Properties of Oxides
L. Klibanov2000-04-01Optical Engineering
Diamond-like carbon (DLC) films were deposited directly on GaAs substrates by a capacitively coupled 13.56 MHz glow discharge in a CH4 plasma. The deposition process for antireflective DLC coating deposition on GaAs was optimized. DLC films of different thicknesses were deposited to investigate IR spectral characteris…
Metal and Thin Film MechanicsSemiconductor materials and devicesDiamond and Carbon-based Materials Research
Hassan Malik2000-04-01Anti-Corrosion Methods and Materials
Work has been performed to investigate the effect of pH on the performance of a tertiary amine possessing a single carboxylic acid group. The efficiency of this inhibitor and speed at which the efficiency increased were able to show a strong pH dependency, indicating that in such systems pH monitoring is important. Me…
Corrosion Behavior and InhibitionHydrogen embrittlement and corrosion behaviors in metalsConcrete Corrosion and Durability
Takafumi Adachi、E. Ojima、B.Zh. Narymbetov 等 6 位作者2000-04-01Chemistry Letters
Abstract Four-probe resistivity measurements were made on an organic semiconductor, β′-(BEDT-TTF)2ICl2 up to 10 Gpa by using a diamond anvil high-pressure cell. The activation energy was decreased with increasing pressure and the metallic phase appeared around 8 Gpa. When the pressure was kept around 10 Gpa, the resis…
Magnetism in coordination complexesOrganic and Molecular Conductors ResearchN-Heterocyclic Carbenes in Organic and Inorganic Chemistry
Yong Uk Lee、Seung Soon Jang、Won Ho Jo2000-04-01Macromolecular Theory and Simulations
The polycondensation of hyperbranched polymers, based on AB2 type monomers, was simulated using an off-lattice Monte Carlo method in order to investigate the polymerization kinetics and microstructures of hyperbranched polymers. The effects of temperature and activation energy of reaction on the conversion rate seem q…
Corrosion Behavior and InhibitionPolymer crystallization and propertiesDendrimers and Hyperbranched Polymers
Ram Oron、Jacob L. Guedalia、Nir Davidson 等 5 位作者2000-04-01Optics Letters
We show an anomalous behavior in a diffractive lens in which the spot size at the focus reaches a minimum at a numerical aperture of ~0.5 and then increases significantly at higher values. Theoretical and experimental results are presented, along with a comparison with refractive aplanatic lenses, in which the anomaly…
Advanced X-ray Imaging TechniquesOptical Coatings and GratingsNear-Field Optical Microscopy