4,149 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
Method for detecting coliform organisms
A method and apparatus are disclosed for determining the concentration of coliform bacteria in a sample. The sample containing the coliform bacteria is cultured in a liquid growth medium. The cultured bacteria produce hydrogen and the hydrogen is vented to a second cell containing a buffer solution in which the hydrogen dissolves. By measuring the potential change in the buffer solution caused by the hydrogen, as a function of time, the initial concentration of bacteria in the sample is determined. Alternatively, the potential change in the buffer solution can be compared with the potential change in the liquid growth medium to verify that the potential change in the liquid growth medium is produced primarily by the hydrogen gas produced by the coliform bacteria
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
Feasibility of mining lunar resources for earth use: Circa 2000 AD. Volume 1: Summary
The feasibility of obtaining lunar minerals for terrestrial uses is examined. Preliminary results gave indications that it will not be economically feasible to mine, refine, and transport lunar materials to Earth for consumption. A broad systems approach was used to analyze the problem. It was determined that even though the procedure was not economically advisable, the concept for the operations is technically sound
Performance considerations for the astrometric telescope facility on the phase 1 space station
The Astrometric Telescope Facility (ATF) is an optical telescope facility of extreme astrometric precision whose principle scientific purpose is the detection and study of planetary systems about nearby stars. With the recent change in the space station program to two phases, the suitability of initial operations from the phase 1 station need to be evaluated. This paper presents the results of such an evaluation for the Astrometric Telescope Facility
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
A consideration of the effects of the slip displacement on fretting fatigue behaviour
Published versio
Vibrations and fractional vibrations of rods, plates and Fresnel pseudo-processes
Different initial and boundary value problems for the equation of vibrations
of rods (also called Fresnel equation) are solved by exploiting the connection
with Brownian motion and the heat equation. The analysis of the fractional
version (of order ) of the Fresnel equation is also performed and, in
detail, some specific cases, like , 1/3, 2/3, are analyzed. By means
of the fundamental solution of the Fresnel equation, a pseudo-process ,
with real sign-varying density is constructed and some of its properties
examined. The equation of vibrations of plates is considered and the case of
circular vibrating disks is investigated by applying the methods of
planar orthogonally reflecting Brownian motion within . The composition of
F with reflecting Brownian motion yields the law of biquadratic heat
equation while the composition of with the first passage time of
produces a genuine probability law strictly connected with the Cauchy process.Comment: 33 pages,8 figure
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