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991.
Zusammenfassung Die vorliegenden Untersuchungen befassen sich mit den Austauschund Adsorptionsmechanismen, die bei der Anreicherung von Spurenelementen, im besonderen von Uran, an Torfen unter natürlichen Bedingungen wirksam sind. Gleichzeitig wird die maximale Ionenaustauschkapazität von Torf für Mg, Fe und U mit zirka 0,3 bis 0,5 mval/g bestimmt.
Herrn Prof. Dr.-Ing.A. Brukl mit herzlichen Wünschen zum 70. Geburtstag gewidmet. 相似文献
Summary The studies reported here dealt with the exchange and adsorption mechanisms that are active in the accumulation of trace elements, especially uranium, in peats under natural circumstances. The maximum ion exchange capacity of peat for Mg, Fe, and U were found to be around 0.3 to 0.5 mval/g.
Résumé Les recherches qui sont exposées ont trait aux mécanismes d'échange et d'adsorption qui interviennent dans les conditions naturelles dans les tourbes, au cours de l'enrichissement des éléments traces, en particulier dans le cas de l'uranium. On détermine simultanément la capacité maximale d'échange ionique de la tourbe pour Mg, Fe et U avec 0,3 à 0,5 mval/g environ.
Herrn Prof. Dr.-Ing.A. Brukl mit herzlichen Wünschen zum 70. Geburtstag gewidmet. 相似文献
992.
J. Großfeld A. Simmer J. van Loon W. Springer S. Juschkewitsch V. Kubelka J. Wagner S. Zuravlev Thompsonwerke W. Normann H. P. Trevithik M. F. Lauro A. Bömer A. Gehrke G. de Belsunce J. I. Lurje F. Fritz Zitek R. Otto A. Halter J. M. Purdy W. G. France W. L. Evans H. P. Kaufmann M. Keller 《Analytical and bioanalytical chemistry》1931,83(5-6):223-230
993.
J. G. M. Bullowa D. J. Porter D. S. Cryder F. B. Varga R. H. Newton K. Bunte W. Litterscheidt F. Schuster R. Graßberger A. Luszczak M. Shepherd H. F. Görlacher M. Jureček L. S. Gregory W. A. Cook J. B. Ficklen Y. Kauko J. Carlberg V. Mantere M. L. Jean S. Mihaéloff A. Klemenc R. Wechsberg G. Wagner E. Hofmann O. Fischinger R. Goubau J. Eeckhout H. Brückner W. Gröbner A. Bloch G. H. Damon H. Kautsky I. Hirsch E. Briner H. Paillard Olga Waldbauer R. Kraus P. Woog R. Sigwalt J. de Saint-Mars 《Analytical and bioanalytical chemistry》1936,104(11-12):422-432
994.
H. Menzel O. Faust J. Reitstötter R. E. Liesegang Teichmann H. Wagner 《Colloid and polymer science》1935,72(2):250-252
Ohne Zusammenfassung 相似文献
995.
Cunningham and Edmonds [4[ have proved that a 2-connected graphG has a unique minimal decomposition into graphs, each of which is either 3-connected, a bond or a polygon. They define the notion of a good split, and first prove thatG has a unique minimal decomposition into graphs, none of which has a good split, and second prove that the graphs that do not have a good split are precisely 3-connected graphs, bonds and polygons. This paper provides an analogue of the first result above for 3-connected graphs, and an analogue of the second for minimally 3-connected graphs. Following the basic strategy of Cunningham and Edmonds, an appropriate notion of good split is defined. The first main result is that ifG is a 3-connected graph, thenG has a unique minimal decomposition into graphs, none of which has a good split. The second main result is that the minimally 3-connected graphs that do not have a good split are precisely cyclically 4-connected graphs, twirls (K
3,n
for somen3) and wheels. From this it is shown that ifG is a minimally 3-connected graph, thenG has a unique minimal decomposition into graphs, each of which is either cyclically 4-connected, a twirl or a wheel.Research partially supported by Office of Naval Research Grant N00014-86-K-0689 at Purdue University. 相似文献
996.
997.
Nikodem Ku
nik Jan Zawadiak Danuta Gilner Angelika Wickol Pawe Wagner Maciej Kubicki 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o549-o550
The title compound, C26H30O4, is one of the first alkyl bis‐peroxides to be structurally characterized. The molecule lies on a centre of inversion and therefore the terminal phenyl rings are parallel. Although there are three aromatic rings in the molecule, the C—O—O—C torsion angle of 163.10 (10)° is close to the value found in Me3COOCMe3. 相似文献
998.
Teles Wagner M. Fernandes Nelson G. Abras Anuar Filgueiras Carlos A. L. 《Transition Metal Chemistry》1999,24(3):321-325
The coordinating ability of the ligand di(2-pyridyl)sulphide, dps, was studied in several situations. Dps behaved as a bidentate chelating agent with SnX4 (X=Cl or Br) and also with Pd and Pt (PdCl2 and K2PtCl4), whereas with [Pt2(PR3)2Cl4], (R = Et or Ph), it formed bridging complexes: [{Pt(PR3)Cl2}2-dps]. The crystal and molecular structure of [{Pt(PEt3)Cl2}2-dps] was determined. This complex, as well as [M(dps)Cl2], (M = Pd or Pt), underwent reactions with SnCl2, which inserts into the M–Cl bonds producing heterobimetallic products, which are important in catalysis. 相似文献
999.
N(B(NMe2)2)(Si(NMe2)3) (Ti(NMe2)3), [N(Si(NMe2)3)(Ti(NMe2)2)]2 und N(SiMe3)(Si(NMe2)3)(Ti(NMe2)3) — Synthesis and Characterization of New Molecular Single-source Precursors for Nitride and Carbonitride Ceramics Synthesis and spectroscopic data of the title compounds are reported. [N(Si(NMe2)3)(Ti(NMe2)2)]2 crystallizes in the space group P1 , a = 8.406(7), b = 10.673(8), c = 10.872(6) Å, α = 68.45(4)°, β = 71.72(4)°, γ = 78.11(7)°, 2 877 diffractometer data (Fo ? 2σFo), R = 0.051. The compound is characterized by a planar four-membered Ti2N2-ring with exocyclic tris(dimethylamino)silyl substituents attached to the nitrogen atoms of the ring. 相似文献
1000.
The model system Pd/TiO2 (110) was used to evaluate the correlation between metal encapsulation and electronic structure of TiO2 crystals. We observed encapsulation of Pd clusters supported on TiO2 crystals, which were heavily Ar+ sputtered, Nb-doped, or reduced by vacuum annealing. In contrast, encapsulation was not observed on unreduced, undoped, or slightly sputtered TiO2 crystals. Our results indicate a strong dependence of the encapsulation process on the electron density in the conduction band of TiO2 and on the space charge formed at Pd/TiO2 interfaces. This behavior is controlled by the initial position of the Fermi energy level (EF) of the metal and the oxide before contact is established. We proved that encapsulation reactions are favored by n-type doping of the oxide and a large work function of the metal. On the basis of this mechanism, we conclude on general trends controlling encapsulation reactions of oxide-supported metal clusters and the strong metal-support interaction (SMSI). 相似文献