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排序方式: 共有162条查询结果,搜索用时 15 毫秒
1.
We construct the complex simple Lie algebras using elementary algebraic geometry. We use our construction to obtain a new
proof of the classification of complex simple Lie algebras that does not appeal to the classification of root systems. 相似文献
2.
3.
4.
From cyclic linear sweep voltammograms of some Cr(III) complexes it is evident that after electron transfer ligand groups are expelled relatively slowly inDMSO and the tetra coordinated complex is formed. The rate constants could be determined in some cases by the methods of cyclic voltammetry. The following compounds were examined: [Cr(en)3]3+, [Cr(acac)(en)2]2+, [Cr(acac)3]. [Cr(dien)2]3+, [Cr(DMSO)6]3+, [Cr(ur)6]3+. For [Cr(en)3]3+ the energy of activation could be determined as well.The dependence of the velocity of ligand elimination on complex structure is discussed.
Untersuchung von Ligandenaustauschreaktionen einiger Cr(III)-Komplexe mittels cyclischer Voltammetrie
Zusammenfassung Bei der Reduktion einiger der folgenden Cr(III)-Komplexe inDMSO läßt sich auf Grund der Voltammogramme auf eine Ligandenabspaltung und Bildung der vierfach koordinierten Cr(II)-Komplexe schließen: [Cr(en)3]3+, [Cr(acac)(en)2]2+, [Cr(acac)3], [Cr(dien)2]3+, [Cr(DMSO)6]3+, [Cr(ur)6]3+. Für das [Cr(en)3]3+ konnten Geschwindigkeitskonstante und Aktivierungsenergie dieser nachgelagerten Reaktion bestimmt werden.Der Einfluß der Struktur des Komplexes auf die Zerfallsgeschwindigkeit wird diskutiert.相似文献
5.
The rates of decomposition and the energies of activation were determined for the thermal dissociation of NiSO4, CuSO4, Cu2(SO4)O, ZnSO4and Zn3(SO4)2O. Linear, parabolic and logarithmic rate laws were found. Kinetics are largely determined by the rate of energy transfer. The reasons for the formation of basic sulfate intermediates are discussed. 相似文献
6.
S. V. Golovkin A. P. Kozhevnikov V. P. Kubarovsky A. I. Kulyavtzev V. F. Kurshetsov A. I. Kushnirenko L. G. Landsberg V. V. Molchanov V. A. Mukhin V. I. Solyanik D. V. Vavilov V. A. Victorov M. Ya. Balatz G. V. Dzubenko A. D. Kamenskii G. K. Kliger V. Z. Kolganov V. S. Lakaev G. S. Lomkatzi A. P. Nilov V. T. Smolyankin V. E. Vishnyakov 《Zeitschrift fur Physik C Particles and Fields》1995,68(4):585-594
In the experiments at the SPHINX facility in 70 GeV proton beam of the IHEP accelerator the coherent diffractive production reactions on carbon nucleip+C [(1385)0
K
++C andp+C[0
K
+]+C were investigated. The evidences for new baryon states were obtained in the study of hyperon-kaon effective mass spectra in these two reactions:X (2050) with massM=(2052±6) MeV and width =(35
–35
+22
) MeV inM[(1385)0
K
+] andX(2000) withM=1999±6 MeV and =91±17 MeV inM[0
K
+]. The unusual features of these massive states (small enough decay widths, anomalously large branching ratios for decays with strange particles emission) make them very serious candidates for cryptoexotic pentaquark baryons with hidden strangeness. 相似文献
7.
It is shown that new parametersX can be defined such that the heat capacity CxT(S/T)x is negative, even when the canonical ensemble [i.e., at fixed T=(U/S)Y and YX] is stable. This implies an extension of the classical theory of polytropes from ideal gases to general fluids. As examples of negative heat capacity systems we treat blackbody radiation and general gas systems with nonsingular T. For the case of a simple ideal gas we even exhibit an apparatus which enforces a constraint X(p, V)=const that makes Cx<0. We then show that it is possible to infer the statistical mechanics of canonicallyunstable systems-for which even the traditional heat capacities are negative-by imposing constraints that stabilize the associated noncanonical ensembles. Two explicit models are discussed. 相似文献
8.
9.
Two problems have long been confused with each other: the gravitational redshift as discussed by the equivalence principle; and the Doppler shift observed by a detector which moves with constant proper acceleration away from a stationary source. We here distinguish these two problems and give for the first time a solution of the former which is exact within the context of the equivalence principle in a sense discussed in the paper. The equivalence principle leads to transformations between flat spacetimes. These are analyzed, and a generalized Lorentz transformation is proposed which covers transformations from inertial to uniformly accelerated frames of reference. 相似文献
10.
Mattson M Alkhazov G Atamantchouk AG Balatz MY Bondar NF Cooper PS Dauwe LJ Davidenko GV Dersch U Dolgolenko AG Dzyubenko GB Edelstein R Emediato L Endler AM Engelfried J Eschrich I Escobar CO Evdokimov AV Filimonov IS Garcia FG Gaspero M Giller I Golovtsov VL Gouffon P Gülmez E Kangling H Iori M Jun SY Kaya M Kilmer J Kim VT Kochenda LM Konorov I Kozhevnikov AP Krivshich AG Krüger H Kubantsev MA Kubarovsky VP Kulyavtsev AI Kuropatkin NP Kurshetsov VF Kushnirenko A Kwan S Lach J Lamberto A 《Physical review letters》2002,89(11):112001
We observe a signal for the doubly charmed baryon Xi(+)(cc) in the charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) in data from SELEX, the charm hadroproduction experiment at Fermilab. We observe an excess of 15.9 events over an expected background of 6.1+/-0.5 events, a statistical significance of 6.3sigma. The observed mass of this state is 3519+/-1 MeV/c(2). The Gaussian mass width of this state is 3 MeV/c(2), consistent with resolution; its lifetime is less than 33 fs at 90% confidence. 相似文献