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1.
Ohne ZusammenfassungDie folgende Untersuchung trug der leider so früh dem Dienste der Wissenschaft durch den Tod entrissene Privatdocent Dr. Hierholzer dahier (gest. 13. Sept. 1871) einem Kreise befreundeter Mathematiker vor. Um sie vor Vergessenheit zu bewahren, musste sie bei dem Mangel jeder schriftlichen Aufzeichnung aus dem Gedächtniss wieder hergestellt werden, was ich unter Beihilfe meines verehrten Collegen Lüroth durch das Folgende möglichst getreu auszuführen suchte. 相似文献
2.
The present paper is aimed to display the performance of the Fourier-Galerkin technique developed earlier by the authors for numerical treatment of localized solutions in
2(-∞, ∞) for higher-order equations. The solitary-wave solution of the Kortweg-de Vries fifth order equation is obtained numerically and compared with approximate results of other authors. 相似文献
3.
Chr. Bargholtz 《Physics of Atomic Nuclei》2002,65(4):593-598
On the basis of gross properties of nuclei, a simple semiempirical equation of state is developed for cold hadronic matter composed of light quarks of two flavors. The source of binding energy in the model is the decreasing asymmetry between the number of up and down quarks in extended regions of overlapping nucleons. The resulting incompressibility of symmetric nuclear matter at equilibrium density is K=324 MeV. The incompressibility decreases rapidly with decreasing density but increases only slowly with increasing density until homogenous quark matter is reached at a density just above three times ordinary nuclear matter density. 相似文献
4.
An ultrabroadband (up to 35 nm FWHM) generation by a pulsed dye laser is reported. The principle of laser operation is based on a recently proposed cavity configuration, which we have termed spatially-dispersive resonator. By means of a prism pair this spreads the various spectral components into different spatial areas in the active medium and thus reduces the competition between them. A generation of a spectrum containing a number of equally spaced lines is also demonstrated. 相似文献
5.
By means of Mössbauer and X-ray structural investigation it was shown that the compounds Sn3S4 and Sn2S3 can be synthesized mechanochemically. The influence of an inert additive on the explosive character of the mechanochemical synthesis of tin sulfides was investigated. A transition from the explosive way of synthesis to the nonexplosive one upon adding great quantities of inert material was observed. A mechanism explaining this phenomenon was suggested. The initiation of a high-temperature synthesis reaction by the heat effect of a mechanochemical explosive reaction was observed for the first time. 相似文献
6.
C. Chr Schüler 《Zeitschrift für Physik B Condensed Matter》1987,68(2-3):325-328
The proton conductivity of three layer-type compounds was studied: H3OTi2NbO7. H2O, HTiNbO5 and HTiTaO5. Measurements were made between 20 °C and 90°C on pellets pressed from crystalline powders and soaked with pure water. The hydrated compound had the highest conductivity, (20°C)-6.3–6.9·10–4 (cm)–1. Acid ions from the exchange process were quite firmly retained in its layer structure and contributed significantly to the measured conductivity. Consistent results were obtained after prolonged washing with water.Dedicated to Professor Harry Thomas on the occasion of his 60th birthday 相似文献
7.
Saturation properties of the dyes in the presence of excited-state absorption and amplified spontaneous emission in the dye are studied theoretically. In the analysis the above two effects are included separately and it is shown that they are deleterious to the pulse-shortening capabilities of the dyes. It is also shown that in the conventional single-pass shortening of laser pulses with saturable dyes large pulse shortening ratios (20) may be expected if the dye saturation is combined with a properly delayed dye generation. 相似文献
8.
We have investigated the suitability of poly-(alkyl--cyanoacrylates) (p-(alkyl-CAc)) for two-photon four-level holographic recording. It is shown that these materials follow indeed a two-photon four-level mechanism with the second absorption step in the near infrared. Light induces the polymerization of residual monomer in the matrix. The reaction is associated with positive density changes. The sensitivity ofp-(alkyl-CAc) depends strongly on composition and age of the sample. Maximum sensitivities achieved are comparable to the so far best-known two-photon four-level ir-sensitive systems. 相似文献
9.
10.
C. Chr. Heuck und G. Middelhoff 《Fresenius' Journal of Analytical Chemistry》1978,290(2):127-128