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1.
We propose a bi-Hamiltonian formulation of the Euler equation for the free n-dimensional rigid body moving about a fixed point. This formulation lives on the physical phase space so(n), and is different from the bi-Hamiltonian formulation on the extended phase space sl(n), considered previously in the literature. Using the bi-Hamiltonian structure on so(n), we construct new recursion schemes for the Mishchenko and Manakov integrals of motion.  相似文献   
2.
Résumé Du cuivre pur (99.999 %) avec différentes tailles de grains a été déformé par laminage (réduction d'épaisseur entre 30 et 90%).Les courbes DSC mettent en évidence le dégagement d'énergie au cours de la recristallisation et montrent que l'énergie emmagasinée par déformation n'est pas sensible à la dimension des grains qui, au contraire, agit sur les paramètres cinétiques de la recristallisation.Dans une région étroite des taux de déformation on observe une variation brutale de l'énergie emmagasinée, de la température du pic DSC et de l'énergie d'activation de la recristallisation.
Pure copper (99.999 %) with various grain sizes was deformed by cold rolling (reduction in thickness 30–90%).DSC curves of energy evolution during recrystallization show that the stored energy of deformation does not depend on grain size, which on the contrary affects the kinetic parameters of recrystallization.Abrupt changes in stored energy, DSC peak temperature and activation energy of recrystallization are observed in a narrow range of deformation amounts.

Zusammenfassung Reines Kupfer (99.999%) von sehr verschiedenen Korngrössen wurde durch Kaltwalzen deformiert (Herabsetzung der Stärke zwischen 30 und 90%).Die DSC-Kurven der Energieabgabe im Verlaufe der Rekristallisation zeigen, daß die durch Deformation entstandene Energiespeicherung gegenüber der Korngrösse nicht abhängig ist, jedoch die kinetischen Parameter der Rekristallisation beeinflußt.In einem engen Bereich der Deformationsgrössen kann eine jähe Änderung der gespeicherten Energie, der Temperatur des DSC-Peaks und der Aktivierungsenergie der Rekristallisation beobachtet werden.

(99.999%) : ( 30–90%). , , . , .
  相似文献   
3.
Series of cyano, dicyano, amidino, and diamidino substituted 2-phenylbenzothiazoles were prepared. Mono- and dicyano substituted benzothiazoles were obtained by condensation of appropriate substituted benzaldehydes with 2-aminothiophenol or 4-amino-3-mercaptobenzonitrile. The appropriate amidines or diamidines were prepared by Pinner reaction. The compounds were tested against breast, prostate, and lung cancer cell lines in a 72 h cytotoxicity assay. Many of the compounds had at 10 μM activity equivalent to 2-(4-aminophenyl)benzothiazole, while four compounds had significantly better activity, particularly in the breast cancer model.  相似文献   
4.
Nanoporous gold thin films have been fabricated through chemical de-alloying of Au-based nanoglass with a nanocolumnar structure, with composition Au40Cu28Ag7Pd5Si20 (at.%), that had previously been deposited by magnetron sputtering. By varying the de-alloying conditions, gold ligaments ranging from 20 to 100?nm were obtained. The microstructure and chemical composition of the as-prepared films were characterised by various techniques. Surface-enhanced Raman scattering (SERS) of thin films was investigated using rhodamine 6G. The results indicate that the main microstructural features with interconnected ligaments and defects of nanoporous gold result in significant SERS enhancement.  相似文献   
5.
6.
ROMPgel-supported tris(triphenylphosphine)rhodium(I) chloride has been prepared and the immobilised catalyst has been effectively employed in selective hydrogenations of a variety of alkenes and terminal alkynes.  相似文献   
7.
13C-enriched carbido carbonyl clusters of the type [M6C(CO) n ] z? (M=Fe,n=16,z=2; M=Ru,n=16 ifz=2 andn=17 ifz=0) have been prepared and their IR spectra observed in the 900?600 cm?1 region; the band shifts occurring upon13 C substitution enable the assignment to the stretching modes of the interstitial C atom. Band patterns reflect the symmetry of the M6C core, but the frequencies seem dependent on other molecular features.  相似文献   
8.
The ALTEA (Anomalous Long Term Effects on Astronauts) detector was used to characterize the radiation environment inside the USLab of the International Space Station (ISS), where it measured the abundances of ions from Be to Fe. We compare the ALTEA results with Alteino results obtained in the PIRS module of the Russian segment of the ISS, and normalize to the high energy Si abundances given by Simpson. These are the first particle spectral measurements, which include ions up to Fe, performed in the USLab. The small differences observed between those made inside the USLab and the Simpson abundances can be attributed to the transport through the spacecraft hull. However, the low abundance of Fe cannot be attributed to only this process.  相似文献   
9.
Novel derivatives of 6-amino-2-phenylbenzothiazole bearing different substituents (amino, dimethylamino or fluoro) on the phenyl ring were prepared as the corresponding hydrochloride salts. 6-Nitro-2-(substituted-phenyl)benzothiazoles (1-6) were synthesized by condensation reactions of substituted benzaldehydes with 2-amino-5-nitrothiophenol. Nitro derivatives were reduced to the amino derivatives with SnCl(2)/HCl.Water soluble hydrochloride salts of 6-amino-2-(substituted-phenyl)benzothiazole (13-19)were prepared using concentrated or gaseous HCl. Compounds 13-19 were found to exert cytostatic activities against malignant human cell lines: cervical (HeLa), breast (MCF-7),colon (CaCo-2), laryngeal carcinoma (Hep-2), and normal human fibroblast cell lines (WI-38).  相似文献   
10.
The efficient synthesis of new amidino, N-isopropylamidino, 2-imidazolinyl substituted benzothiazoles and 2-aminothiophenoles by the Pinner reaction is described. The novel ring opening of benzothiazole with ammonia and ethylenediamine was found, and a plausible reaction mechanism proposed. The ring opening with ethylenediamine is selective and applicable to compounds bearing hydrolytically and amonolytically unstable substituents. Different amidino-substituted 2-aminothiophenoles were isolated in zwitterionic and disulfide form and their structures were determined by X-ray crystal structure analysis.  相似文献   
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