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  • 1
    Electronic Resource
    Electronic Resource
    Correlation and X-ray scattering. I. Density matrix formulation (1970)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 26 (1970), S. 579-586 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Equations suitable for obtaining values of the coherent and total intensities of X-ray radiation scattered by N-electron atomic systems are developed from the 1- and 2-particle density matrices. Although electron scattering within the first Born approximation can be treated in the same fashion, a separate consideration of this problem is not required since the scattered electron and X-ray intensities are related by equations well established in the literature. The general formalism presented here is such that it easily allows the computation of X-ray scattering factors and intensities to extend beyond the Hartree–Fock approximation, thereby incorporating electron correlation effects. Evaluation of the relevant equations requires the natural orbitals or the natural spin orbitals and the natural geminals or the natural spin geminals. These can always be obtained from the 1- and 2-particle density matrix analyses of the N-electron wavefunction Ψg characterizing the atomic state. In the event that Ψg is approximated by a single Slater determinant, the equation for the total scattered X-ray intensity reduces to the familiar Waller–Hartree result.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739470001493
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  • 2
    Electronic Resource
    Electronic Resource
    A new analytic approximation to atomic incoherent X-ray scattering intensities (1975)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 31 (1975), S. 391-392 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: A new analytic approximation to atomic incoherent X-ray scattering intensities is proposed. Unlike other approximations in the literature, the present function has the correct asymptotic behaviour at both large and small values of s. Fits to the incoherent intensities calculated by Cromer are presented for all atoms from He through Am.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S056773947500085X
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  • 3
    Electronic Resource
    Electronic Resource
    Correlation and X-ray scattering. II. Atomic beryllium (1970)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 26 (1970), S. 586-594 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: In order to assess the importance of correlation effects with respect to the Hartree–Fock (HF) results, values of the coherent, total and incoherent scattered X-ray intensities were computed for the 1S ground state of atomic beryllium. Natural spin orbitals (NSO) and natural spin geminals (NSG) constructed from the accurate configuration interaction (CI) wavefunction of A.W. Weiss were used in the evaluation of these X-ray quantities from previously derived density matrix expressions. Values were also computed from the two-configuration wavefunction of Watson, which accounts for the 2s–2p near degeneracy effect. As expected, the CI results for the total intensity differ from their HF counterparts but the magnitudes of the absolute deviations are not as large as those observed for the coherent intensity values. Although the HF results for the coherent intensity are in reasonably good agreement with the CI values, conclusions based on the Møller–Plesset theorem must be made with caution. The largest percentage deviations between HF and CI results, however, are observed for the incoherent intensity. All calculations reported here were verified by the use of sum rules.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S056773947000150X
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  • 4
    Electronic Resource
    Electronic Resource
    PREDICTING THE SUMMER PEAK BIOMASS OF FOUR SPECIES OF BLUE-GREEN ALGAE (CYANOPHYTA/CYANOBACTERIA) IN SWEDISH LAKES (1987)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 23 (1987), S. 0 
    Details
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: : Stepwise multiple regression analysis was used to develop models predicting the summer peak biomass of Aphanizomenon flos-aquae, Anabaena flos-aquae, Oscillatoria agardhii, and Microcystis aeruginosa in four Swedish lakes. These analyses suggest that while epilimnetic total phosphorus concentration is the principal predictor of their peak biomass, other factors such as station mean depth, water temperature, total nitrogen, and total CO2 concentration are also important.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1752-1688.1987.tb00818.x
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  • 5
    Electronic Resource
    Electronic Resource
    Removal of Internally Deposited Plutonium (1958)
    [s.l.] : Nature Publishing Group
    Nature 181 (1958), S. 1792-1793 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Table l. EFFECT OF CHBLATING AGENTS ON PLUTONIUM DEPOSITION AND BEMOVAL AS PERCENTAGE OF DOSE ADMINISTERED PER GRAM OF DRY TISSUE The dosage was 0 -3 m.mole per rat of each material with 0 -2 m.mole calcium gluconate being administered with the chelating agent. There were 6-10 rats in each ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/1811792a0
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  • 6
    Electronic Resource
    Electronic Resource
    A role for tubular compression in the management of psoriasis (2005)
    Oxford, UK : Blackwell Science Ltd
    Clinical and experimental dermatology 30 (2005), S. 0 
    Details
    ISSN: 1365-2230
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2230.2005.01824.x
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  • 7
    Electronic Resource
    Electronic Resource
    Relativistic X-ray Elastic Scattering Factors for He–Ar from Dirac–Hartree–Fock Wave Functions (1996)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 52 (1996), S. 649-658 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: X-ray and electron elastic scattering factors for He through Ar ground states have been computed from Dirac–Hartree–Fock (DHF) wave functions. Differing from earlier studies, the present DHF wave functions are not restricted to single configurations and will go into the nonrelativistic Hartree–Fock (HF) ground states when the speed of light c ⇒ \infty. The relativistic effects have been analyzed through the differences of scattering factors calculated at DHF and HF levels of theory. It has been found that the effects become stronger as the nuclear charge increases and anomalous behavior observed in the literature for C, N, O, Si, P and S is due to the use of either single- or average-energy multiconfiguration DHF wave functions to extract the relativistic effects for these systems preventing attainment of the correct nonrelativistic limit. Scattering factors of common ions of the first- and second-row elements and the valence state of C and Si are also given.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0108767396003960
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  • 8
    Electronic Resource
    Electronic Resource
    High-accuracy ab initio form factors for the hydride anion and isoelectronic species (1992)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 48 (1992), S. 70-71 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Form factors computed from extremely accurate wave functions are tabulated for H−, He, Li+ and Be2+ together with fits to Gaussian expansions of the standard form.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0108767391005883
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  • 9
    Electronic Resource
    Electronic Resource
    Prevention of Plutonium Deposition by Desferrioxamine- B (1964)
    [s.l.] : Nature Publishing Group
    Nature 204 (1964), S. 899-900 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Table 1. STABILITY CONSTANTS [ML] L -4U [M] [L] Where M = metal, L = chelating agent (ref. 2) 'Common' chemical name of L -^Fez, -K^cai EDTA Ethylenediaminetetraacetic acid 25-1 DTPA Diethylenetriaminepentaaceticacid 28-6 13FAB Desferrioxamine B 30-6 10-7 14-4 10-1 18-5 2-6 28-0 From these ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/204899a0
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  • 10
    Electronic Resource
    Electronic Resource
    Behaviour of hartree-fock and hartree-fock-slater (Xα) atomic form factors and electron momentum distributions for two-, three- and four-electron ions (1972)
    Springer
    The European physical journal 255 (1972), S. 83-92 
    Details
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The atomic form factor and the radial electron density in momentum space, from the solutions of the α-parameterized Hartree-Fock-Slater (Xα) equations, are studied within the framework ofZ −1 expansion theory for the two-, three- and four-electron ions in their ground state configurations (1s 2), (1s 1s′ 2s), and (1s 2 2s 2), and compared with the corresponding Hartree-Fock quantities.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01391674
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