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931.
932.
M. Metcalf G. Neuhofer F. Niebergall M. Regler H. Stier K. Winter
J. J. Aubert
X. De Bouard V. Lepeltier L. Massonnet H. Pessard M. Vivargent T. R. Willitts M. YvertW. Bartl
M. Steuer 《Physics letters. [Part B]》1972,40(6):703-707The time-dependence of the decay rate of initially pure K0 into the final state (π+π−π0) has been studied in search for the decay kS0→π+π−π0. No evidence is found in a sample of 384 observed events. The ratio of the CP -violating KS0 amplitude and the KL0 amplitude is η+−0 = (0.13−0.20+0.17) + i(0.17−0.26+0.27); the ratio of the CP-conserving KS0 amplitude and the KL0 amplitude is < 0.4. The energy dependence of the K0→π+π−π0 matrix element is found to be a+−0 = −0.31 ± 0.03. 相似文献
933.
J. P. Mariot P. Michaud S. Lauer D. Astruc A. X. Trautwein F. Varret 《Hyperfine Interactions》1983,14(4):333-346
A Mössbauer study of the title paramagnetic Fe(O) complex was carried out from 4.2 K to 250 K. The electric field gradient (EFG) tensor was found to be temperature independent in accordance with the well isolated nature of state3A2g. Measurements in an applied magnetic field of 6 T confirmed the paramagnetic nature (S=1) of the complex and showed the EFG tensor to be negative. From the thermal variation of the hyperfine field we determined the spin hamiltonian constant D=14 K and find the g-value to be close to the free electron value. Semi-empirical molecular orbital (MO) calculations were carried out with a modelized molecule of D6h symmetry; results are in good agreement with the experimental values (for both the electronic and magnetic properties). 相似文献
934.
A possible cooling of electrons at low temperatures is predicted from a newly-developed approach to steady-state nonlinear transport in the presence of an electric field. The lowering of the electron temperature below the lattice temperature occurs in low-impurity samples and at such a current density for which the average drift velocity of the carriers is near the sound speed. 相似文献
935.
W. Beusch E. Polgar D. Websdale K. Freudenreich F.X. Gentit P. Muhlemann J. Pernegr W. Wetzel P. Astbury J.G. Lee M. Letheren G. Bellini M. Di Corato F. Palombo P.G. Rancoita G. Vegni 《Physics letters. [Part B]》1975,55(1):97-100
In the reaction π? + A → π+π?π? + A at 15.1 GeV/c the coherently produced 3π mass spectrum has a broad peak around 1.1 GeV which consists mainly of a JP = 1+ state and of a smaller fraction of 0-. Comparing the observed dependence of the production of these diffractive states on the atomic weight A of the target nuclei with the optical model, we have studied the absorption of the produced states in nuclear matter. We have found the following values of the absorption cross-sections: σ2(0-) = 49?7+9 mb and σ2(1+) = 15.8?1.3+1.5 mb. 相似文献
936.
B. Pietrzyk R. Barate P. Bareyre P. Bonamy P. Borgeaud M. David F.X. Gentit G. Laurens Y. Lemoigne G. Villet S. Zaninotti P. Astbury A. Duane G.J. King B.C. Nandi R. Namjoshi D.M. Websdale J. Wiejak T. Marshall 《Physics letters. [Part B]》1982,113(1):105-112
A lepton-pair trigger was used to select a hadronic system in different flavour and colour states: properties of the transformation of this system into hadrons were measured in terms of charge flow, multiplicity distribution, and fragmentation function. It is observed that, while the effects of flavour are clearly seen, the colour degrees of freedom are not observed in the region of low pT. 相似文献
937.
938.
P. Longevialle J. Einhorn J. P. Alazard L. Diatta P. Milliet C. Monneret Q. Khuong-Huu X. Lusinchi 《Journal of mass spectrometry : JMS》1971,5(2):171-186
The presence of a hydroxyl group in steroidal amines, amides and imines, may profoundly influence their fragmentation in the mass spectrometer. This fragmentation is initiated by the rearrangement of the hydroxylic hydrogen on the nitrogen containing groups and products ions characteristic of the OH site in the molecule. Sometimes this may occur even when the two groups are situated at remote positions. 相似文献
939.
T.L. Chen X.M. Li S. Zhang X. Zhang 《Applied Physics A: Materials Science & Processing》2005,80(1):73-76
(200)-oriented Pt and Ir electrode films have been epitaxially grown on MgO/Si(100) by in situ pulsed-laser deposition (PLD). A comparison of crystallinity and surface morphology of both electrode films was made. It was found that both electrode films featured remarkable atomic-scale smooth surfaces and had the same epitaxial relationship with substrates. Different from the noncompact surface morphology of the Pt film, the morphology of the Ir film offers a rectangular grain shape and the grains are arrayed regularly and compactly. The difference in the surface morphology of both electrode films is briefly explained in terms of the degree of species saturation. PACS 81.15.Fg; 68.55.Jk; 61.14.Hg; 68.55.-a; 81.15.-z; 77.55.+f 相似文献
940.
X. Zhao J. Wang H.L.W. Chan C.L. Choy H. Luo 《Applied Physics A: Materials Science & Processing》2005,80(3):653-658
Microdomain-macrodomain transformations and phase transitions in 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 single crystals were investigated by studying their relative permittivity under various dc bias at constant heating and cooling rates. The orientation dependence of the bias field effect was revealed by examining the temperature dependence of relative permittivity as a function of crystal orientation (the 111, 011 and 001 directions) and dc bias field. The crystals have a microdomain rhombohedral ferroelectric state in the ferroelectric phase under zero dc bias. External bias field could modulate the domain state and induce a macrodomain state in the crystals. Also, it is proposed that the dc bias applied along the 001 or 011 direction could induce a tetragonal ferroelectric phase or an orthorhombic ferroelectric phase, respectively, in an intermediate temperature range. PACS 77.80.-e; 77.22.-d; 81.40.-z 相似文献