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81.
We discuss how the spectral changes of quarkonia at T
c can reflect the ‘critical’ behaviour of QCD phase transition. Starting from the temperature dependencies of the energy density
and pressure from lattice QCD calculation, we extract the temperature dependencies of the scalar and spin-2 gluon condensates
near T
c. We also parametrize these changes into the electric and magnetic condensate near T
c. While the magnetic condensate hardly changes across T
c, we find that the electric condensate increases abruptly above T
c. Similar abrupt change is also seen in the scalar condensate. Using the QCD second-order Stark effect and QCD sum rules,
we show that these sudden changes induce equally abrupt changes in the mass and width of J/ψ, both of which are larger than 100 MeV at slightly above T
c.
相似文献
82.
Application of a modified Polonovski reaction for serratinine (1) resulted in generation of serratezomine A (2) with a novel seco-serratinine-type skeleton recently isolated from the club moss Lycopodium serratum var. serratum. This biomimetic transformation supports a biogenetic pathway proposed for serratezomine A (2). The absolute stereochemistry of serratezomine A (2) was established by an induced exciton chirality and modified Mosher methods. 相似文献
83.
Selective shielding of one side of the pyridinium face by way of intramolecular cation-pi complex formation enabled nucleophiles to attack only from the non-shielded side, and consequently, chiral 1,4-dihydropyridines were produced stereoselectively with up to 99% de. The structure of the cation-pi complex was elucidated by 1H NMR studies and X-ray analysis. 相似文献
84.
Morita H Kawaguchi H Yoshimura T Tsukurimichi E Shimasaki C Horn E 《Chemistry (Weinheim an der Bergstrasse, Germany)》2000,6(21):3976-3983
5-(N-p)-Toluenesulfonyl)iminothianthrenes, whose sulfur atoms are oxidized to a sulfoxide or sulfone at the 10-position, were hydrolysed readily in high yield to N-unsubstituted-sulfilimines by using concentrated H2SO4. During hydrolysis, 10-monoxy-5-N-unsubstituted-sulfilimines were obtained as a separable mixture of the cis and trans isomers. The stereochemical interconversion of these compounds was studied under both hydrolytic and thermal conditions and their structures were elucidated by using X-ray crystallography. 相似文献
85.
We give a functional Korovkin-type theorem onB(X), the space of bounded complex-valued functions on an arbitrary setXand investigate a BKW-operator onB(X) for a finite collection of test functions with a suitable property and a seminorm defined by a finite subset ofX. 相似文献
86.
87.
88.
The convergence of the arithmetic-geometric mean procedure is checked for complex variables. The procedure is shown to be useful for the evaluation of the complete elliptic integrals of the first and second kinds with complex modulus. It is suggested that the procedure will be useful also for the numerical calculation of the elliptic integrals and the Jacobian elliptic functions with complex modulus in general. 相似文献
89.
90.