Johann G. Meier、Ralf Ruhmann、Joachim Stumpe2000-01-18Macromolecules
Upon irradiation with linearly polarized light a photoorientation process occurs in spin-coated films of polymethacrylates with 4-hexyloxyazobenzene side groups containing para methoxy and trifluoromethoxy tail groups. It results in the induction of an oblate orientational distribution perpendicular to the electric fi…
Liquid Crystal Research AdvancementsAdvanced Physical and Chemical Molecular InteractionsMolecular spectroscopy and chirality
Pitt Supaphol、Joseph E. Spruiell2000-01-18Journal of Applied Polymer Science
Isothermal crystallization behavior after partial or complete melting of syndiotactic polypropylene was investigated by differential scanning calorimetry (DSC). On partial melting, the total concentration of predetermined nuclei was found to decrease with increasing fusion temperature and increasing time period that t…
Polymer crystallization and propertiesbiodegradable polymer synthesis and properties
Frank Dietsche、Yi Thomann、Ralf Thomann 等 4 位作者2000-01-18Journal of Applied Polymer Science
New acrylic nanocomposites consisting of methyl methacrylate (MMA)/n-dodecylmethacrylate (LMA) copolymers and intercalated layered silicates were prepared. The silicates were based upon bentonite which was rendered organophilic by ion exchange with N,N,N,N,-dioctadecyl dimethyl ammonium ions. Morphological, thermal, m…
Polymer Nanocomposites and PropertiesPolymer composites and self-healingSilicone and Siloxane Chemistry
Chun Shan Wang、Ching Hsuan Lin2000-01-18Journal of Applied Polymer Science
A series of advanced epoxy resins with various epoxy equivalent weights were synthesized from a reactive phosphorus-containing diol, 2-(6-oxido-6H-dibenz[c,e][1,2]oxaphosphorin-6-yl)-1,4-dihydroxy phenylene and diglycidyl ether of bisphenol A and then cured with 4,4′-diaminodiphenyl sulfone, phenol novolac, or dicyand…
Flame retardant materials and propertiesSynthesis and properties of polymersPhosphorus compounds and reactions
Zhigang Wang、Benjamin S. Hsiao、E. B. Sirota 等 5 位作者2000-01-18Macromolecules
The early stages of polymer melt crystallization using fractionated isotactic polypropylene ( i PP) as a model system were investigated via simultaneous synchrotron small-angle X-ray scattering (SAXS)/wide-angle X-ray diffraction (WAXD) and laser light scattering (LS) techniques. Since the crystallinity in the early s…
Polymer crystallization and propertiesPolymer Nanocomposites and PropertiesCultural Heritage Materials Analysis
Martin H. Weik、Raimond B. G. Ravelli、Gitay Kryger 等 10 位作者2000-01-18OpenAlex
Radiation damage is an inherent problem in x-ray crystallography. It usually is presumed to be nonspecific and manifested as a gradual decay in the overall quality of data obtained for a given crystal as data collection proceeds. Based on third-generation synchrotron x-ray data, collected at cryogenic temperatures, we…
Protein Structure and DynamicsEnzyme Structure and FunctionEnzyme function and inhibition
D. Nabi Saheb、J. P. Jog2000-01-17Advances in Polymer Technology
Blends of polybutylene terephthalate (PBT) with very low-density polyethylene (VLDPE) have been studied. The blends are immiscible owing to the differences in the polarities of the component polymers. Thermal studies using a differential scanning calorimeter showed that the blending does not change the crystallinity a…
Polymer crystallization and propertiesPolymer Nanocomposites and Propertiesbiodegradable polymer synthesis and properties
Yasuchika Hasegawa、Takashi Ohkubo、Kensaku Sogabe 等 7 位作者2000-01-17Angewandte Chemie
Eine stabile NdIII-Lumineszenz in einem organischen Lösungsmittel, dessen Moleküle C-H-Bindungen enthalten, wurde erstmals durch Komplexierung von NdIII mit langkettigen perfluoralkylierten Liganden wie Bis(perfluoroctylsulfonyl)aminat (pos) erreicht. Der Komplex [Nd(pos)3] hat eine Emissions-Quantenausbeute von 3.0±0…
Organometallic Complex Synthesis and CatalysisFluorine in Organic ChemistryLanthanide and Transition Metal Complexes
M. Grossmann、O. Lohse、D. Bolten 等 8 位作者2000-01-17Applied Physics Letters
Two different failure modes for a ferroelectric memory cell caused by imprint, the read failure due to the loss of polarization, and the write failure due to the shift of the hysteresis loop are investigated. The quasistatic hysteresis loop allows us to distinguish which failure mode is dominating in a ferroelectric r…
Ferroelectric and Piezoelectric MaterialsElectronic and Structural Properties of OxidesFerroelectric and Negative Capacitance Devices
William Jo、D. C. Kim、Jongin Hong2000-01-17Applied Physics Letters
We report charge retention in preferentially c-axis oriented ferroelectric Pb(Zr,Ti)O3 (PZT) thin films on LaNiO3 by electrostatic force microscopy. The surface charge density of the PZT films was observed as a function of time in a selected area where a region is single poled and another region is reverse poled. Rete…
Ferroelectric and Piezoelectric MaterialsAcoustic Wave Resonator TechnologiesAdhesion, Friction, and Surface Interactions
Yoon–Ki See、Junhoe Cha、Taihyun Chang 等 4 位作者2000-01-17Langmuir
The glass transition temperature ( T g ) of poly( tert -butyl methacrylate) (PtBMA) Langmuir−Blodgett (LB) films relative to that of spin-coated films on a silicon substrate is investigated by ellipsometry and X-ray reflectivity. The T g of spin-coated films on an oxide-free silicon wafer decreases as the film thickne…
Liquid Crystal Research AdvancementsMaterial Dynamics and PropertiesFluid Dynamics and Thin Films
Nancy St. Clair、Yi-Fong Wang、Alexey L. Margolin2000-01-17Angewandte Chemie International Edition
Horse liver alcohol dehydrogenase was crystallized in the presence of its cofactor. The cross-linked enzyme crystals (CLECs) produced showed good catalytic activity without the addition of extra cofactor (see scheme). The enantioselectivity and stereochemical preference of the CLEC were the same as with the soluble en…
Protein Structure and DynamicsEnzyme Structure and FunctionPorphyrin Metabolism and Disorders
Nobuo Kimizuka、Sang‐Ho Lee、Toyoki Kunitake2000-01-17Angewandte Chemie International Edition
A way to prepare molecular electronic wires in organic media is the solubilization of one-dimensional mixed-valence complexes with varied metal species through the formation of amphiphilic supramolecular assemblies (see picture). Dissociation and reassembly of the complex was detected as thermochromism in the interval…
Magnetism in coordination complexesPorphyrin and Phthalocyanine ChemistryOrganic and Molecular Conductors Research
Stefan P. Hau‐Riege、Carl V. Thompson2000-01-17Applied Physics Letters
We have performed in situ transmission electron microscopy studies of abnormal grain growth in electroplated copper films at room temperature and 55 °C, starting minutes after the plating process by electroplating directly onto electron-transparent membranes. A kinetic analysis indicates that the grains that grow abno…
Semiconductor materials and devicesElectrodeposition and Electroless CoatingsCopper Interconnects and Reliability
Jun Zhou、John B. Goodenough、B. Dąbrowski 等 5 位作者2000-01-17Physical Review Letters
The temperature dependence of the resistivity $\ensuremath{\rho}(T)$ and of the dc magnetic susceptibility $\ensuremath{\chi}(T)$ were measured on high-quality $L{\mathrm{NiO}}_{3}$ $(L\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\mathrm{La},\mathrm{Pr},\mathrm{Nd},{\mathrm{Nd}}_{0.5}{\mathrm{Sm}}_{0.5})$ sample…
Ferroelectric and Piezoelectric MaterialsMagnetic and transport properties of perovskites and related materialsElectronic and Structural Properties of Oxides
Jie‐Sheng Huang、Xianru Sun、Sarana Ka‐Yan Leung 等 5 位作者2000-01-17Chemistry - A European Journal
Reactions of dioxoruthenium(VI) porphyrins, [Ru(VI)O2(Por)], with p-chloroaniline, trimethylamine, tert-butylamine, p-nitroaniline, and diphenylamine afforded bis(amine)ruthenium(II) porphyrins, [Ru(II)(Por)(L)2] (L-p-ClC6H4NH2, Me3N, Por=TTP, 4-Cl-TPP; L=tBuNH2, Por = TPP, 3,4,5-MeO-TPP, TTP, 4-Cl-TPP, 3,5-Cl-TPP) an…
Porphyrin and Phthalocyanine ChemistryMetal-Catalyzed Oxygenation MechanismsCO2 Reduction Techniques and Catalysts
Xuefei Huang、Babak Borhan、Barry Rickman 等 5 位作者2000-01-17Chemistry - A European Journal
A nonempirical exciton chirality circular dichroic (CD) method for determining the absolute configurations of primary monoamines with amino group directly linked to the stereogenic center is described. Conventional exciton chirality CD method cannot be applied to these compounds since they lack the two sites for attac…
Photosynthetic Processes and MechanismsPorphyrin and Phthalocyanine ChemistryMolecular spectroscopy and chirality
Walter Kaminsky、Frank Hartmann2000-01-17Angewandte Chemie International Edition
The catalytic degradation of polyethylene to short-chain hydrocarbons is possible with zirconium hydride compounds (see picture), and represents the first step in the reversal of Ziegler - Natta polymerization. Thus, even in the case of polyolefins the important target of plastics recycling, the recovery of reusable m…
Recycling and Waste Management TechniquesPolymer Science and PVC
Z.E. Serna、Luís Lezama、M. Karmele Urtiaga 等 7 位作者2000-01-17Angewandte Chemie International Edition
A combination of azido and dipyridylketone (dpk) ligands led to the isolation of the tetranuclear Ni(II) complex 1 (dpkOH and dpkOCH(3) result from solvolysis of dpk). The complex exhibits ferromagnetic behavior, and its structure can be described as a dicubane unit with two missing vertices (see picture).
Magnetism in coordination complexesLanthanide and Transition Metal ComplexesMetal-Catalyzed Oxygenation Mechanisms
Regula Sieber、Silvio Decurtins、H. Stoeckli‐Evans 等 8 位作者2000-01-17Chemistry - A European Journal
In the three-dimensional oxalate network structures [M(II)(bpy)3][M(I)-M(III)(ox)3] (ox= C2O4(2-); bpy = 2,2'-bipyridine) the negatively charged oxalate backbone provides perfect cavities for tris-bipyridyl complex cations. The size of the cavity can be adjusted by variation of the metal ions of the oxalate backbone.…
Magnetism in coordination complexesLanthanide and Transition Metal ComplexesMetal-Catalyzed Oxygenation Mechanisms