2,770 research outputs found
Cooperative domain type interlayer -bond formation in graphite
Using the classical molecular dynamics and the semiempirical Brenner's
potential, we theoretically study the interlayer sigma bond formation, as
cooperative and nonlinear phenomena induced by visible light excitations of a
graphite crystal. We have found several cases, wherein the excitations of
certain lattice sites result in new interlayer bonds even at non-excited sites.
We have also found that, a new interlayer bond is easier to be formed around a
bond, if it is already existing. As many more sites are going to be excited,
the number of interlayer bonds increases nonlinearly with the number of excited
sites. This nonlinearity shows 1.7 power of the total number of excited sites,
corresponding to about three- or four-photon process.Comment: 7 pages, 8 figure
Raised polyamines in erythrocytes from melanoma-bearing mice and patients with solid tumours
The levels of polyamines (putrescine, spermidine and spermine) in erythrocytes and plasma were studied using Cloudman S-91 melanoma grown in the lungs of DBA/2 mice. Polyamine levels and the numbers of tumour-cell colonies in the lungs were determined at weekly intervals. Putrescine levels in both erythrocytes and plasma significantly increased 1 week after tumour inoculation. Three weeks after inoculation, however, putrescine levels in the erythrocytes showed a greater increase than those in plasma. Spermidine and spermine levels were initially high at 2 weeks in plasma and at 4 weeks in erythrocytes. However, by 6 weeks the spermidine levels showed a greater increase in erythrocytes than in plasma. These data suggest that erythrocytes may absorb and store polyamines released into the circulation
Disturbances of both cometary and Earth's magnetospheres excited by single solar flares
In the solar wind a comet plays the role of a windvane that moves three-dimensionally in the heliomagnetosphere. Among the solar systems bodies, only comets have a wide range of inclination angles of their orbital planes to the ecliptic plane ranging from 0 to 90 deg. Therefore, observations of cometary plasma tails are useful in probing the heliomagnetospheric conditions in the high heliolatitudinal region. A comet can be compared to a polar-orbiting probe encircling the Sun. We will introduce two rare cases in which the magnetospheres of both the comet and the Earth are disturbed by a single solar flare
Novel phase transition and the pressure effect in YbFe2Al10-type CeT2Al10 (T=Fe, Ru, Os)
We have succeeded in growing single crystals of orthorhombic CeT2Al10 (T=Fe,
Ru, Os) by Al self-flux method for the first time, and measured the electrical
resistivity at pressures up to 8 GPa, the magnetic susceptibility and specific
heat at ambient pressure. These results indicate that CeT2Al10 belongs to the
heavy fermion compounds. CeRu2Al10 and CeOs2Al10 show a similar phase
transition at T0 = 27.3 and 28.7 K, respectively. The temperature dependences
in the ordered phases are well described by the thermally activated form,
suggesting that partial gap opens over the Fermi surfaces below T0. When
pressure is applied to CeRu2Al10, T0 disappears suddenly between 3 and 4 GPa,
and CeRu2Al10 turns into a Kondo insulator, followed by a metal. The similarity
of CeT2Al10 under respective pressures suggests a scaling relation by some
parameter controlling the unusual physics in these compounds.Comment: 9 pages, 5 figure
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