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91.
Microsatellite structures in the context of human evolution 总被引:2,自引:0,他引:2
Six microsatellite - or short tandem repeat (STR) - systems with uniform repetitive sequences (HumTH01, HumCD4, HumFES/FPS, HumF13B, HumTPO, HumLPL) and three compound repeat systems (HumVWA, HumFIBRA, D21S11) were used, including data from the literature, to determine genetic distances among eight populations worldwide. The TH01- and VWA homologous loci in nonhuman primates (chimpanzees, gorillas, orangutans, rhesus monkeys, ring-tailed lemurs) were compared and found to be shorter than in humans. Microsatellites of lower complexity were most efficient for the separation of major ethnic groups. The loci of higher complexity showed a leveling of the diversity differences among populations, which could be attributed to higher mutation rates. 相似文献
92.
93.
Jonathan V. Caspar B.Patrick Sullivan Edward M. Kober Thomas J. Meyer 《Chemical physics letters》1982,91(2):91-95
Values of non-radiative decay rate constants (knr) and emission energies (Ecm) have been obtained for Os(Phen3)2+ in a series of solvents and the results are consistent with the energy gap law. For hydroxylic solvents like water or methanol related studies suggest the existence of strong, specific contributions to the vibrational trapping energy of the solvent. 相似文献
94.
Sixteen low-lying electronic states of NaLi are investigated by SCF/valence Cl calculations including core polarization effects by means of an effective potential. Spectroscopic constants are obtained with estimated uncertainties of ΔRe ? 0.01 Å, Δωe ? 0.6 cm?1 and ΔDe ? 80 cm?1. From a comparison of experimental and theoretical G(υ) values, we suggest a ground-state dissociation energy of 7093 ± 5 cm?1. Using our rovibrational energies and recently measured excitation lines, we are able to improve the Te values and dissociation energies of five excited states to an accuracv of ±8 cm?1. 相似文献
95.
96.
97.
Ternary Halides of the A3MX6 Type. II. The System Ag3?xNaxYCl6: Synthesis, Structures, Ionic Conductivity . The influence of the substitution of Ag+ by Na+ ions on the crystal structure and the ionic conductivity of Ag3YCl6 (stuffed LiSbF6-type structure) has been investigated. The system Ag3?xNaxYCl6 forms a complete solid solution. The stuffed LiSbF6-type structure is stable for all compositions. For compounds with Na+ contents of x > 1.67, the cryolite-type structure is observed as the high-temperature form. The transition temperature decreases steadily with increasing Na+ content. The “end member” phase Na3YCl6 transforms at 243 K from the monoclinic cryolite-type structure to the stuffed LiSbF6-type structure (trigonal, R3 ; a = 697.3(1), c = 1 868.4(14) pm, Z = 3; R = 0.094; Rw = 0.069). The crystal structures of Ag1.3Na1.7YCl6 (trigonal, R3 ; a = 691.5(2), c = 1 853.7(6) pm, Z = 3; R = 0.099, Rw = 0.081) and AgNa2YCl6 (trigonal, R3 ; a = 691.7(1), c = 1 853.9(5) pm, Z = 3; R = 0.099, Rw = 0.064) have also been determined. Both chlorides crystallize like Ag3YCl6 and Na3YCl6-I in the stuffed LiSbF6-type structure. The monovalent cations, Ag+ and Na+, are distributed over the five octahedral voids that are occupied by the Ag+ ions alone in Ag3YCl6. The ionic conductivity for compounds within the solid solution Ag3?xNaxYCl6 decreases with increasing Na+ content. The values for Na3YCl6 (σ = 1 · 10?6 Ω?1 cm?1 at T = 500 K) are by 2.5 to 3.5 orders of magnitude smaller than those for Ag3YCl6 (σ = 6 · 10?4 Ω?1 cm?1 at T = 500 K). 相似文献
98.
[Rb2(H2O)2][Re3(μ-Cl)3Br7(H2O)2]2 · H2O, a Mixed Halide-Hydrate with the Anionic Dimer {[Re3(μ-Cl)3Br7(H2O)2]2 · H2O}2? [Rb2(H2O)2][Re3(μ-Cl)3Br7(H2O)2]2 · H2O crystallizes as dark redbrown single crystals from an hydrobromic-acid solution of ReCl3 and RbBr at 0°C. An important feature of the crystal structure (monoclinic, C2/c; a = 1494.61(8); b = 835.71(4); c = 3079.96(19) pm; β = 97.801(4)°; Vm = 573.9(4) cm3mol?1; R = 0.060; Rw = 0.038) is the connection of two anions [Re3(μ-Cl)3Br7(H2O)2]? via a water molecule to dimers, {[Re3(μ-Cl)3Br7(H2O)2]2 · H2O}2?. These dimeric units are contained in slabs that are stacked in the [001] direction and held together by Rb+ cations and crystal water. 相似文献
99.
100.
Peter Esser Bettina Pohlmann Hans-Dieter Scharf 《Angewandte Chemie (International ed. in English)》1994,33(20):2009-2023
The light of the sun can be used directly for changing chemical structures photochemically. Any industrial application must conform to the limitations imposed by the spectral distribution of the photons from the sun, the interruptions to the radiation due to the day/night rhythm, and the weather. In this review, we describe the photochemical potential of the sun, give a fundamental treatment of the concept of photoreactors driven by sunlight (abbreviated to solar photoreactors), and give an account of the realization of this concept in the first pilot plant on the “Plataforma Solar de Almeria” in southern Spain and in other activities in this field. Based on experimental data from photochemical investigations on the pilot plant scale, possibilities, limitations, and the potential growth of solar photochemistry are described. Solar photochemistry, in our opinion, is a technique which could make a contribution to the chemistry of the future because of its photochemical synthesis potential, the avoidance of waste products, and the direct utilization of the sun, not only as a primary energy source, but also as a reaction partner. 相似文献