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91.
92.
Gunther Pabst 《Discrete Mathematics》1976,16(1):53-56
All axiom systems are derived which define finite affine planes and consist of certain combinatorial inequalities or equalities involving the number of lines connecting two distinct points the number of lines through a point the number of points on a line, the total number of points or the total number of lines. The result given in Dembowski book Finite Geometries are corrected. 相似文献
93.
P. Sandel W. Vogt S. Broda D. Jüngst und M. Knedel 《Fresenius' Journal of Analytical Chemistry》1978,290(2):129-130
Ohne Zusammenfassung
Contributions to computer assisted diagnostics: II. Grouping of biochemical thyroid parameters without considering clinical diagnosis相似文献
94.
The unimolecular fragmentations of internal energy selected allene molecular ions ( 1 +) have been investigated by photoelectron-photoion coincidence spectroscopy. The energy dependence of the branching ratio between the two most important fragmentation channels is reported, together with values for the kinetic energy release during fragmentation. Loss of an hydrogen atom from 1 + is interpreted to proceed via two paths, yielding different isomeric forms of C3H with different kinetic energy release values. 相似文献
95.
Gunther E. Molau 《Journal of membrane science》1981,8(3):309-330
The field of heterogeneous ion exchange membranes is reviewed briefly. Specific advantages and disadvantages of heterogeneous ion exchange membranes are discussed compared with those of homogeneous ion exchange membranes. p]The development of heterogeneous ion exchange membranes is presented in historical perspective. The electrochemistry of ion-selective membranes began with Ostwald in 1890. After the classical work of Michaelis (1925) with collodion membranes, the first fully synthetic ion exchange membranes were prepared by Zhukov (1933) and Wassenegger (1940), based on sulfonated phenol—formaldehyde resins. These initial membranes, which were of the homogeneous type found no practical uses. The era of commercially useful ion exchange membranes began with the work of Wyllie (1948), Juda (1950), Bodamer (1953) and their collaborators who prepared heterogeneous ion exchange membranes by embedding ion exchange particles into polymer matrices. p]Methods for making heterogeneous ion exchange membranes include compression-molding of polymer powders, compounding on hot rolls, latex or solvent blending in situ generation of either the matrix or the ion exchange material. Microheterogeneous ion exchange membranes can be made from block and graft copolymers, interpolymers snake-cage resins, similar techniques and materials. p]Even though the first commercial ion exchange membranes were heterogeneous, the interest in this type of membranes subsided later. As polymer science progressed, speciality monomers and polymers were being made which opened the way to the preparation of quite sophisticated homogeneous ion exchange membranes of satisfactory mechanical strength. However, the possibilities of heterogeneous ion exchange membranes are by no means exhausted and this field may warrant further exploration, applying modern methods and materials and thus progressing beyond the relatively crude heterogeneous ion exchange membranes of the pioneer times. 相似文献
96.
J. Bartke M. Deutschmann H.G. Kirk P. Sixel L. Becker H. Vogt R. Hartmann H. Plothow D. Kocher D.R.O. Morrison P. Porth K. Eskreys K. Olkiewicz K. Doroba T. Hofmokl 《Nuclear Physics B》1977,120(1):1-13
Interactions in which the baryon is emitted forwards in the c.m.s. are studied in 8 and 16 GeV/cπ+p collisions. These interactions are interpreted as representing baryon exchange. The properties of such off-shell N annihilation events are studied. It is found that the multiplicity distribution of the multi-pion system as a function of the effective mass for events with |upp| < 1 GeV2 is the same as for real annihilations. 相似文献
97.
Dietmar Vogt 《Mathematische Annalen》1972,196(4):281-292
Ohne Zusammenfassung 相似文献
98.
The optical properties of uranium sulphide single crystals have been determined for the first time. An excellent agreement is found between the structure in the optical spectrum and the results of a self-consistent cellular multiple scattering calculation. The results evidence that the 5? electrons form a resonance state at EF and that the 5??6d coupling produces a dip in the 6d density of states near EF which is responsible for many peculiar properties of US. 相似文献
99.
Changes in the magnetic field-temperature phase diagram of CeSb with pressure have been determined up to 6kbar by magnetization measurements on a single crystal. High magnetic fields up to 70 kOe have been applied along a four fold axis of the rock-salt type structure. The features of the phase diagram are not changed by pressure except for a shift towards high temperature. The saturated magnetic moment and the hysteresis of the transition fields are independent of pressure. Variation of exchange energy with volume is deduced from the experimental results. It is shown that the effect of pressure and the magnetic volume anomaly at 0 K are essentially due to the variation of the exchange energy in the ferromagnetic (001) planes. 相似文献
100.
Dr. Pierre Junod Dr. A. Menth Dr. O. Vogt 《Zeitschrift für Physik B Condensed Matter》1969,8(5):323-370
This report reviews the most important publications, as well as many unpublished measurements by the authors. The influence of the cubic crystal field on the magnetic properties of binary compounds containing the trivalent Ions Pr3+, Sm3+, Tm3+ and Yb3+ is studied. Crystalfield- and exchange parameters (molecularfield approximation) were determined for the ferromagnetic nitrides GdN, TbN, DyN, HoN and ErN. The mechanism of the electrical conductivity is still unknown. 相似文献