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91.
The only known examples of Anosov diffeomorphisms are hyperbolic automorphisms of infranilmanifolds, and the existence of such automorphisms is a really strong condition on the rational nilpotent Lie algebra determined by the lattice, so called an Anosov Lie algebra. We prove that n⊕?⊕n (s times, s≥2) has an Anosov rational form for any graded real nilpotent Lie algebra n having a rational form. We also obtain some obstructions for the types of nilpotent Lie algebras allowed, and use the fact that the eigenvalues of the automorphism are algebraic integers (even units) to show that the types (5,3) and (3,3,2) are not possible for Anosov Lie algebras. 相似文献
92.
93.
P. Gippner K. D. Schilling F. Stary E. Will K. Heidel S. M. Lukyanov Yu. E. Penionzhkevich V. S. Salamatin H. Sodan G. G. Chubarian R. Schmidt 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(4):433-434
TotaT kinetic energy vs. fragment mass distributions have been measured in the reactions of64Zn projectiles with114Sn,natAg and139La nuclei at incidence energies of 20–50% above the Coulomb barrier. Conclusions are drawn on the possible influence of nuclear structure effects on the energy dissipation and the mass drift behaviour of the present collision systems. 相似文献
94.
95.
To enhance the volatility of the copper precursor in the copper deposition process, it was envisioned that N,N'-unsymmetrically substituted 1,3-diketimines should be more volatile than their symmetrically substituted counterparts. A variety of Cu(II) (N,N'-unsymmetrically substituted 1,3-diketiminate) complexes have been synthesized and have proven to be much more volatile than their symmetrical counterparts. This makes the new materials particularly attractive to the ALD and CVD processes. Among the new compounds, 8-a and 8-b are sublimable even at room temperature. 相似文献
96.
The high-spin states of 95Tc have been studied in the reaction 93Nb(α, 2n)95Tc using inbeam spectroscopy of both γ-rays and conversion electrons. A new sequence of negative-parity states extending up to angular momentum was found to exist within an excitation energy interval of 4.1 MeV. The positive-parity states are in remarkable agreement with the predictions of a simplified shell-model approach on the basis of coupled excitations of proton and as well as neutron configurations. A similar analysis for the negative-parity states shows qualitative agreement with the experimental results. 相似文献
97.
98.
J. M. Will W. Eisfeld K. F. Renk S. Haussühl 《Applied Physics A: Materials Science & Processing》1983,31(4):191-193
Tunable detection of high-frequency phonons in LaF3 is reported. Phonons generated by a heat-pulse technique are detected by phonon-induced fluorescence from magnetically split energy levels of Er3+ impurity ions. Evidence for a strongly frequency-dependent lifetime of acoustic phonons at frequencies above 600 GHz is found. The lifetime is attributed to spontaneous anharmonic phonon decay. 相似文献
99.
Ju-Nam Y Bricklebank N Allen DW Gardiner PH Light ME Hursthouse MB 《Organic & biomolecular chemistry》2006,4(23):4345-4351
We report the synthesis and structural characterisation of a new family of stable phosphonioalkylthiosulfate zwitterions, R3P+ (CH2)nS2O3- (R = Ph or Bu, n = 3,4,6, 8 or 10) which behave as cationic masked thiolate ligands with applications in the functionalisation of gold nanoparticles, having potential as new diagnostic biorecognition systems. The ligands were prepared by treatment of omega-bromoalkylphosphonium salts with sodium thiosulfate. The crystal and molecular structures of the zwitterions (R = Ph, n = 3) and (R = Bu, n = 3) were determined. A series of phosphonioalkanethiolate-capped gold nanoparticles dispersed in water was prepared by borohydride reduction of potassium tetrachloroaurate in the presence of the zwitterions in a dichloromethane-water system. UV-visible spectroscopy and scanning transmission electron-microscopy indicated that capped nanoparticles of ca. 5 nm diameter were present. 相似文献
100.
A pyrrolylamidothiourea deprotonates in the presence of one equivalent of not only fluoride, but also acetate, benzoate or dihydrogen phosphate in DMSO solution with structural studies using synchrotron radiation confirming thiourea deprotonation in the solid state. 相似文献