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M. Voss W. Weiss R. Winkler 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1986,1(2):157-166
From 17 transitions in the singly ionized Sb II spectrum the hyperfine structure (A andB splitting constants) of the complete excited configurations 5p6s and 5p6p were determined by means of optical interference spectroscopy. In addition, a theoretical analysis both of the fine structure and also of the hyperfine structure was carried out (in the case of 5p6p of the general typenpn′p for the first time in literature). For the 3 levels 5p6p 3 P 1, 5p7p 3 D 2 and 5p6p 1 P 1 a different classification was found and consistent values for the fine structure parameters, mixing coefficients and single electron hyperfine structure splitting parametersa nl ik andb nl ik were obtained. The three new determinations in Sb II of the quadrupole moment (in barn) of121Sb (Q(5p6s)=?0.55(5);Q(5p6p)=?0.57(5) from the 5p-electron andQ(5p6p)=?0.7(2) from the 6p-electron) are well agreeing with each other but differ to former values from SbI. The core polarization and isotope shift of the lines, however, are compatible with our former results in SbI. 相似文献
14.
Multiparticle fractal aggregation 总被引:1,自引:0,他引:1
Richard F. Voss 《Journal of statistical physics》1984,36(5-6):861-872
Kinetic fractal aggregation in a particle bath where a fractionf of the sites are initially occupied is studied withd=2 computer simulations. Independent particles diffusing to a fixed cluster produce an aggregate with fractal dimensionD 1.7 up to a correlation length(f). At larger lengthsD2.(f) asf 0. When the particles remain fixed but the cluster undergoes a rigid random walkD appears constant at larger scales but varies withf. D 1.95 at largef andD 1.7 asf 0. In both cases, the aggregate sizeN(t) grows with timet
(f)
. Aggregation on a surface by independently diffusing particles produces shapes reminiscent of electrochemical dendritic growth. The dependence of growth rate and geometry is studied as a function of particle concentration and sticking probability. 相似文献
15.
Fletcher MT Wood BJ Brereton IM Stok JE De Voss JJ Kitching W 《Journal of the American Chemical Society》2002,124(26):7666-7667
The origins of the oxygen atoms in 1,7-dioxaspiro[5.5]undecane (1) and hydroxyspiroacetal (2) from Bactrocera cacuminata, and in 2,8-dimethyl-1,7-dioxaspiro[5.5]undecane (3) and hydroxyspiroacetal (4) from B. cucumis, have been investigated by incorporation studies from both [(18)O(2)]-dioxygen and [(18)O]-water. Combined GC-MS examination and high-field NMR analysis have demonstrated that all oxygen atoms in 1 and 2 from B. cacuminata are dioxygen derived, but in contrast, the spiroacetals 3 and 4 from B. cucumis incorporate one ring oxygen from water and one ring oxygen (and the hydroxyl oxygen in 4) from [(18)O(2)]-dioxygen. These results reveal not only the generality of monoxygenase mediation of spiroacetal formation in Bactrocera sp., but also an unexpected complexity in their biosynthesis. A general paradigm accommodating these and other observations is presented. 相似文献
16.
Gundula Voss Michael Gradzielski Jürgen Heinze Helmut Reinke Carlo Unverzagt 《Helvetica chimica acta》2003,86(6):1982-2004
Two new types of 4,4′,7,7′‐tetraalkoxyindigotins, 1a – f and 2a – f along with the new N‐substituted indigotins 4e – f , were synthesized from dinitrobenzaldehydes 5a – f , which were prepared from 2‐hydroxy‐5‐methoxybenzaldehyde ( 7 ) via dialkoxybenzaldehydes 6a – f (Scheme). The new dialkoxyindigotin 3g was obtained from dialkoxybenzaldehyde 6g via nitrobenzaldehyde 8g . The 1,4‐dialkoxy‐2,3‐dinitrobenzenes 9 were isolated as by‐products. The 4,4′,7,7′‐tetraalkoxy‐5,5′‐diaminoindigotins 1 are soluble in organic solvents, and their solutions are green, which is highly uncommon for indigotins and is primarily caused by electronic effects of substituents, steric effects playing a minor role. The indigotins 1 produce a strong red shift of the longest‐wavelength absorption and negative solvatochromism indicating the predominance of polar resonance structures in the ground state. Tautomeric structures were excluded. These indigotins are valuable compounds for technical applications, for synthetic purposes, and for analytical studies. SANS (Small‐angle neutron scattering) experiments showed that certain 4,4′,7,7′‐tetraalkoxy‐5,5′‐diaminoindigotins 1 form rod‐like aggregates in solution. The similarly substituted 4,4′,7,7′‐tetraalkoxy‐5,5′‐dinitroindigotins 2 are far less soluble. They produce red monoanions (preferably dimers) and bluish‐purple dianions in organic solvents. 相似文献
17.
18.
M. Voss W. Weiss B. Buchholz R. Winkler 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1986,1(2):151-156
By optical interference and VUV spectroscopy the doublet system of SbI 5p 26s was investigated, so that now the hyperfinestructure of all 8 levels of 5p 26s (A- andB-splitting constants) are known. From the analysis we receive a spin-orbit parameter ζ5p =3,538(57) cm?1 and from the hyperfine-analysis single electron splitting constantsa 5p 01 =52.4(4.6),a 5p 10 =?1.6(7.3),a 5p 12 =72.3(2.3),a 6s 10 =91.7(4.1),b 5p 02 =?49.6(1.1) andb 5p 11 =30.4(3.2) (all values in mK). For all calculations in the fs- and hfs-analysis the 5p 26s 2 D 3/2 has to be excluded (see discussion). With the figures given above the quadrupole moment121 Q(5p 26s)=?0.44(3) barn was obtained. It is in good agreement with the121 Q(5p 3). For the core-polarization by the 5p electron in the innerfieldns-shells (n=1, 2, 3, 4, 5) and the unpaired 6s electron a field of +500(300) kG was obtained. 相似文献
19.
Silbernagel KM Jechorek RP Kaufer AL Johnson RL Aleo V Brown B Buen M Buresh J Carson M Franklin J Ham P Humes L Husby G Hutchins J Jechorek R Jenkins J Kaufer A Kexel N Kora L Lam L Lau D Leighton S Loftis M Luc S Martin J Nacar I Nogle J Park J Schultz A Seymore D Smith C Smith J Thou P Ulmer M Voss R Weaver V 《Journal of AOAC International》2005,88(3):750-760
A multilaboratory study was conducted to compare the VIDAS LIS immunoassay with the standard cultural methods for the detection of Listeria in foods using an enrichment modification of AOAC Official Method 999.06. The modified enrichment protocol was implemented to harmonize the VIDAS LIS assay with the VIDAS LMO2 assay. Five food types--brie cheese, vanilla ice cream, frozen green beans, frozen raw tilapia fish, and cooked roast beef--at 3 inoculation levels, were analyzed by each method. A total of 15 laboratories representing government and industry participated. In this study, 1206 test portions were tested, of which 1170 were used in the statistical analysis. There were 433 positive by the VIDAS LIS assay and 396 positive by the standard culture methods. A Chi-square analysis of each of the 5 food types, at the 3 inoculation levels tested, was performed. The resulting average Chi square analysis, 0.42, indicated that, overall, there are no statistical differences between the VIDAS LIS assay and the standard methods at the 5% level of significance. 相似文献
20.
Summary A new method is proposed for the inclusion of the critical parameter * of some convex operator equationu=Tu (appearing e.g. in thermal explosion theory). It is based on the fact that for a fixed Newton's method starting with a suitable subsolution is not monotonically if and only if >*. Several numerical examples arising from nonlinear boundary value problems illustrate the efficiency of the method. 相似文献