The Centers of a Radical Ring
Abstract It is shown that the nth center of a radical ring coincides with that of its adjoint group, from which a result of Jennings is sharpened and a conjecture of his is confirmed.
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Background correction in XPS: Comparison of validity of different methods
Abstract We investigate the validity of methods for background correction in XPS by comparing determined peak intensity ratios with theory. For Ag, Pt and Au, peaks are considered for which possible errors in the inelastic electron mean free path and in the energy dependence of the analyser response function have mini…
Dating thermal anomalies in sedimentary basins: the diagenetic history of clay minerals in the Triassic sandstones of the Paris Basin, France
Abstract Rhaetian (Upper Triassic) sandy horizons were sampled from the Paris Basin from SW to NE, crosscutting the Rhaetian at different depths from outcrop in the NE to 2700 m in the centre of the basin. The smallest day sub-fractions (<0·2 μ m) from the deepest samples consist mainly of illite and chlorite havin…
Synthesis, crystal structure, magnetic susceptibility, and single-crystal EPR studies of bis(diazafluorenone)dichlorocopper(II): a novel Cu(NN)2X2 system with an unusual distortion
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis, crystal structure, magnetic susceptibility, and single-crystal EPR studies of bis(diazafluorenone)dichlorocopper(II): a novel Cu(NN)2X2 system with an unusual distortionC. Balagopalakrishna, M. V. Rajasekharan, S. Bott, J. L. Atwood, and B. L. RamakrishnaCite this…
Carbon filament growth on platinum catalysts
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCarbon filament growth on platinum catalystsW. T. Owens, N. M. Rodriguez, and R. T. K. BakerCite this: J. Phys. Chem. 1992, 96, 12, 5048–5053Publication Date (Print):June 1, 1992Publication History Published online1 May 2002Published inissue 1 June 1992https://pubs.acs.org/d…
Infrared spectra and structure of acetylene on sodium chloride (100)
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfrared spectra and structure of acetylene on sodium chloride (100)S. Keith Dunn and George E. EwingCite this: J. Phys. Chem. 1992, 96, 13, 5284–5290Publication Date (Print):June 1, 1992Publication History Published online1 May 2002Published inissue 1 June 1992https://doi.o…
Epiphytic Diatoms on Cladophora glomerata in the Colorado River, Arizona: Longitudinal and Vertical Distribution in a Regulated River
Flagstaff, AZ 86011 ABSTRACT-Seventy-eight taxa of diatoms were identified from the epiphytic community of Cla- dophoraglomerata in the Colorado River through Glen and Grand Canyons. Achnanthes affinis, Cocconeis pediculus, Diatoma vulgare, and Rhoicosphenia curvata made up 80% of the diatom epiphyton community within…
Metal-Insulator Transition with Oxygen Content in CaVO3-y
To date, CaVO 3- y has been reported and believed to be one of the typical metallic oxides. From our detailed study, however, it has been found that this system shows insulating properties with stoichiometric oxygen content. This insulator phase was obtained by oxidation of as-cast single crystals. The magnetic suscep…
The First Complex with a σ2π4 Triple Bond between Vanadium Atoms in a Ligand Framework of Fourfold Symmetry—[V2{(p‐CH3C6H4)NC(H)N(p‐C6H4CH3)}4]
The long quest for a VV triple bond has finally met with success, as shown by the synthesis of the title compound 1. A short intermetallic distance and high magnetic anisotropy indicate strong interaction between the vanadium centers. R = p-CH3C6H4.
Symmetrical and unsymmetrical quadruply aza bridged closely interspaced cofacial bis(5,10,15,20-tetraphenylporphyrins). 3. Interplanar distances, proton NMR chemical shifts, and the catalysis of the electrochemical reduction of oxygen
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSymmetrical and unsymmetrical quadruply aza bridged closely interspaced cofacial bis(5,10,15,20-tetraphenylporphyrins). 3. Interplanar distances, proton NMR chemical shifts, and the catalysis of the electrochemical reduction of oxygenRafik Karaman, Seungwon Jeon, Orn Almarss…
Comparison of the Vibrational Spectra and Assignments for α -Syndiotactic, β -Syndiotactic, Isotactic, and Atactic Polystyrene and Toluene
Vibrational assignments for α-syndiotactic polystyrene are made with the use of parallel and perpendicular polarization of uniaxially oriented film, and by comparison of vibrational data and assignments for toluene and atactic and isotactic polystyrene. Vibrational assignments are given for a cast film of β-syndiotact…
Spin-polarized electron gun for electron spectroscopies
A spin-polarized electron gun for electron spectroscopies is described in detail. The gun consists of an electron source based on a negative electron affinity GaAs photocathode coupled to an appropriate transport electron optics. The gun has been designed with the aid of ray-tracing analysis and then accurately tested…
An EXAFS study on the so-called "cobalt-molybdenum-sulfur" phase in cobalt/carbon and cobalt-molybdenum/carbon, compared with a Moessbauer emission spectroscopy study
EXAFS measurements were performed on four sulfided catalysts with the same compn. as their 57Co-contg. counterparts which were previously characterized by Moessbauer emission spectroscopy. The Co species in Co/C catalysts with a Co-Mo-S-like Moessbauer emission spectrum after sulfidation at 373 K is similar to the spe…
Kinetics of End Crosslinking in Dense Polymer Melts
The kinetics of the end crosslinking process in linear-polymer melts is studied using molecular-dynamics simulations. Starting from an equilibrated melt, tetrafunctional crosslinkers are attached randomly to a fraction x of the chain ends. The system is then allowed to evolve. When a free end comes within a short reac…
Investigation of short-range Al,Si order in synthetic anorthite by 29 Si MAS NMR spectroscopy
Spectroscopic data are presented for a series of synthetic anorthite samples crystallized from a glass of the same composition and annealed at 1400°C for times of 1mn to 179h. The NMR spectra resemble those of natural Al,Si ordered An-rich feldspars but contain peaks at more negative chemical shifts, indicating the pr…
Postadsorptive transition in fibrinogen adsorbed to polyurethanes: Changes in antibody binding and sodium dodecy1 sulfate elutability
Residence time-dependent changes in fibrinogen after adsorption to six different polyurethanes were examined by measuring polyclonal antifibrinogen binding to the adsorbed protein. The amount of adsorbed fibrinogen that could be eluted by sodium dodecyl sulfate (SDS) was also measured. Baboon fibrinogen was first adso…
Effects of polycarbonate molecular structure on the miscibility with other polymers
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffects of polycarbonate molecular structure on the miscibility with other polymersC. K. Kim and D. R. PaulCite this: Macromolecules 1992, 25, 12, 3097–3105Publication Date (Print):June 1, 1992Publication History Published online1 May 2002Published inissue 1 June 1992https:/…
Preparation of Potassium Tantalate Niobate by Sol–Gel Method
Perovskite potassium tantalate niobate (KTN) powders and thin films were synthesized from a metal alkoxide solution. Homogeneous KTN coating solutions were prepared from KOC 2 H 5 , Ta(OC 2 H 5 ) 5 , and Nb(OC 2 H 5 ) 5 in absolute ethanol. The precursor crystallized to pyrochlore at ∼ 650°C, and then to perovskite at…
On the flow stress of [100]- and [111]-oriented Cu-Mn single crystals: A transmission electron microscopy study
Cu-Mn single crystals oriented for multiple slip with [111] and [100] axis have been deformed in tension at room temperature. The Mn content was 0.8 at.% for the [111] and 3at.% for the [100] crystals. The observed decrease in the workhardening rate with increasing reduced shear stress τ—τ0 coincides with the linear d…
Carbon-13 NMR spectroscopic determination of the magnitude of the .beta.-silyl stabilization effect in 1-mesitylvinyl cations
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCarbon-13 NMR spectroscopic determination of the magnitude of the .beta.-silyl stabilization effect in 1-mesitylvinyl cationsHans Ullrich Siehl and Frank Peter KaufmannCite this: J. Am. Chem. Soc. 1992, 114, 12, 4937–4939Publication Date (Print):June 1, 1992Publication Histo…