Chelate-modified polymers for atmospheric gas chromatography

Chromatographic materials were developed to serve as the stationary phase of columns used in the separation of atmospheric gases. These materials consist of a crosslinked porous polymer matrix, e.g., a divinylbenzene polymer, into which has been embedded an inorganic complexed ion such as N,N'-ethylene-bis-(acetylacetoniminato)-cobalt (2). Organic nitrogenous bases, such as pyridine, may be incorporated into the chelate polymer complexes to increase their chromatographic utility. With such materials, the process of gas chromatography is greatly simplified, especially in terms of time and quantity of material needed for a gas separation

XPS study of the chemical structure of the nickel/silicon interface

The chemical nature of the Ni/Si, Ni/Ni_(2)Si and Si/Ni_(2)Si interfaces have been investigated using x‐ray photoelectron spectroscopy. Peak position, line shapes, and envelope intensities are used to probe the compositional structure of these systems. Two approaches have been employed: one approach examines the advancing planar silicide front by dynamically monitoring the in situ formation of Ni_(2)Si. This has the advantage of allowing examination of a realistic interface which is bounded on either side by an extended solid. The second approach follows the development of the Si/Ni interface using UHV depositions of thin layers of Ni on Si . ^(4)He^+ backscattering is used to follow the progression of the thin film reaction and to provide quantitative information on atomic composition. These experiments demonstrate that the Ni/Ni_(2)Si interface consists of a Ni‐rich silicide transitional phase while the Si/Ni_(2)Si interface shows a transitional structure which is correspondingly Si‐rich. Intensity analysis indicates that these interfacial regions are at least 22 Å wide for α‐Si substrates and 9–14 Å wide for crystalline Si. The as‐deposited Ni/Si interface cannot be described as a unique single‐phase, but rather as a chemically graded transitional region showing a composition which varies from Si‐rich to Ni‐rich silicides

Newton's method and Baker domains

We show that there exists an entire function f without zeros for which the associated Newton function N(z)=z-f(z)/f'(z) is a transcendental meromorphic functions without Baker domains. We also show that there exists an entire function f with exactly one zero for which the complement of the immediate attracting basin has at least two components and contains no invariant Baker domains of N. The second result answers a question of J. Rueckert and D. Schleicher while the first one gives a partial answer to a question of X. Buff.Comment: 6 page

The atomic orbitals of the topological atom

The effective atomic orbitals have been realized in the framework of Bader’s atoms in molecules theory for a general wavefunction. This formalism can be used to retrieve from any type of calculation a proper set of orthonormalized numerical atomic orbitals, with occupation numbers that sum up to the respective Quantum Theory of Atoms in Molecules (QTAIM) atomic populations. Experience shows that only a limited number of effective atomic orbitals exhibit significant occupation numbers. These correspond to atomic hybrids that closely resemble the core and valence shells of the atom. The occupation numbers of the remaining effective orbitals are almost negligible, except for atoms with hypervalent character. In addition, the molecular orbitals of a calculation can be exactly expressed as a linear combination of this orthonormalized set of numerical atomic orbitals, and the Mulliken population analysis carried out on this basis set exactly reproduces the original QTAIM atomic populations of the atoms. Approximate expansion of the molecular orbitals over a much reduced set of orthogonal atomic basis functions can also be accomplished to a very good accuracy with a singular value decomposition procedure

A Link Between the Semi-Major Axis of Extrasolar Gas Giant Planets and Stellar Metallicity

The fact that most extrasolar planets found to date are orbiting metal-rich stars lends credence to the core accretion mechanism of gas giant planet formation over its competitor, the disc instability mechanism. However, the core accretion mechanism is not refined to the point of explaining orbital parameters such as their unexpected semi-major axes and eccentricities. We propose a model, which correlates the metallicity of the host star with the original semi-major axis of its most massive planet, prior to migration, considering that the core accretion scenario governs giant gas planet formation. The model predicts that the optimum regions for planetary formation shift inward as stellar metallicity decreases, providing an explanation for the observed absence of long period planets in metal-poor stars. We compare our predictions with the available data on extrasolar planets for stars with masses similar to the mass of the Sun. A fitting procedure produces an estimate of what we define as the Zero Age Planetary Orbit (ZAPO) curve as a function of the metallicity of the star. The model also hints that the lack of planets circling metal-poor stars may be partly caused by an enhanced destruction probability during the migration process, since the planets lie initially closer to the central stars.Comment: Nature of the replacement: According to recent simulations, the temperature profile, T, is more adequately reproduced by beta = 1 rather than beta = 2. We have introduced a distance scale factor that solves the very fast drop of T for low metallicity and introduces naturally the inferior distance limit of our ZAPO. Under this modification all the fitting process was altere

Heteroepitaxy of deposited amorphous layer by pulsed electron-beam irradiation

We demonstrate that a single short pulse of electron irradiation of appropriate energy is capable of recrystallizing epitaxially an amorphous Ge layer deposited on either or Si single-crystal substrate. The primary defects observed in the case were dislocations, whereas stacking faults were observed in samples

Epitaxial growth of deposited amorphous layer by laser annealing

We demonstrate that a single short pulse of laser irradiation of appropriate energy is capable of recrystallizing in open air an amorphous Si layer deposited on a (100) single-crystal substrate into an epitaxial layer. The laser pulse annealing technique is shown to overcome the interfacial oxide obstacle which usually leads to polycrystalline formation in normal thermal annealing

The final COS-B database: In-flight calibration of instrumental parameters

A method for the determination of temporal variation of sensitivity is designed to find a set of parameters which lead to maximum consistency between the intensities derived from different observation periods. This method is briefly described and the resulting sensitivity and background variations presented

Brief Studies

The Function of the Law in Christian Preaching Ezra’s Bible School Basic Books for the Exeget

Brief Studies

A New Greek-English Lexicon of The New Testament Thou Art Mad The Witnesses of Christ\u27s Resurrectio