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971.
In a previous paper, we proposed the infinite sub-layer quark model, in which the proton and the neutron are made up of an infinite number of point-like (structure-less) quarks u and anti-quarks u CP at an infinite sub-layer level. In this paper, we propose that the dark matter is also made of an infinite number of quarks u and anti-quarks u CP . A pair of the ultimate quarks u and anti-quarks u CP would be produced in the first moments after the Big Bang and then remain as the dark matter for all time, stable against decay and subject only to the weak interaction and gravity. It is then shown that CP is violated in the doublet of u and u CP quarks to account for the asymmetry of the number of particles and anti-particles in the present universe. Furthermore, it is shown that the Higgs bosons are composed of u and u CP dark matter particles and give the masses to gauge bosons, quarks and leptons.  相似文献   
972.
Image quality of MeV transmission electrons is an important factor for both observation and electron tomography of microns-thick specimens with the high voltage electron microscope (HVEM) and the ultra-HVEM. In this work, we have investigated image quality of a tilted thick specimen by experiment and analysis. In a 3 MV ultra-HVEM, we obtained transmission electron images in amplitude contrast of 100 nm gold particles on the top surface of a tilted 5 μm thick amorphous epoxy-resin film. From line profiles of the images, we then measured and evaluated image blurring, contrast, and the signal-to-noise ratio (SNR) under different effective thicknesses of the tilted specimen and accelerating voltages of electrons. The variation of imaging blurring was consistent with the analysis based on multiple elastic scattering. When the effective thickness almost tripled, image blurring increased from ~3 to ~20 nm at the accelerating voltage of 3 MV. For the increase of accelerating voltage from 1 to 3 MV in the condition of the 14.6 μm effective thickness, due to the reduction of multiple scattering effects, image blurring decreased from ~54 to ~20 nm, and image contrast and SNR were both obviously enhanced by a factor of ~3 to preferable values. The specimen thickness was shown to influence image quality more than the accelerating voltage. Moreover, improvement on image quality of thick specimens due to increasing the accelerating voltage would become less when it was further increased from 2 to 3 MV in this work.  相似文献   
973.
We have succeeded in making peapod structures with vertically aligned multi-walled carbon nanotubes (MWNTs), grown on a silicon substrate using hot filament chemical vapor deposition. Opening the tips of the MWNTs was performed at 600 C using oxygen and then C60 molecules were deposited on them to fill their inner spaces. We confirmed that the MWNTs were open at the tips and filled with C60 molecules using transmission electron microscopy. In addition, it has been determined that MWNTs can be filled with other materials, such as molybdenum oxide.  相似文献   
974.
Summary In this paper, we observe how Lévy's stochastic area looks when we see it through various topologies in the Wiener space. Our theorem implies that it is quite natural from the viewpoint of topology to define a distinct skeleton of Lévy's stochastic areaS(w) for each distinct topology in the Wiener space, or equivalently, for each distinct abstract Wiener space on which the Wiener measure andS(w) are realized. Thus we cannot determine its intrinsic skeleton in the theory of abstract Wiener spaces.  相似文献   
975.
The CO2-laser-induced infrared multiple photon decomposition of natural CBr2F2 in the presence of oxygen has been examined as a function of pulse number (30–1500), reactant pressures (CBr2F2, 10–150 Torr and O2, 5–90 Torr), laser line [9P(8)–9P(32)], and laser fluence (1–3 J cm–2) to optimize irradiation conditions for 13C-enrichment. CF2O was the main carbon containing product and afterwards was converted into CO2 via hydrolysis. A small amount of C2Br2F4 was detected only under extreme conditions, for example, at high laser fluences or wavenumbers close to an absorption band. The 13C-atom fraction of the final product CO2 was found to be 20–80%, depending on experimental conditions. The two-stage IRMPD process proposed previously has been examined in further detail in the present study. First, CBr2F2 containing about 30% of 13C was prepared in the 13C-selective IRMPD of natural CHClF2 in the presence of Br2. The second-stage IRMPD of the CBr2F2 in the presence of oxygen under selected conditions resulted in the high enrichment of 13C beyond 90%.  相似文献   
976.
IR spectra were measured for an antitubercular agent, D-cycloserine (CS), and the hydrolyzate, β-aminooxy-D-alanine (AOA) and the dimer, cis-3, 6-bis(aminooxymethyl)-2, 5-piperadinedione (CS-dimer) at various pHs in aqueous solutions. Molecular species existing in the ionic equilibria were characterized by the pH dependence of the spectra. Band assignments were carried out by reference to the spectra of D20 solutions and those of related compounds. Spontaneous transformation of CS to CS-dimer was observed by the IR spectra for the neutral aqueous solution. The spectral evidence suggested that the non-ionic form of CS plays a key role in the dimerization process.  相似文献   
977.
Optical characteristics of the retroreflector in space (RIS) on the Advanced Earth Observing Satellite (ADEOS) in orbit were tested using a second harmonics Nd:YAG laser. The intensity of reflection from the RIS was analyzed with an intensified charge coupled device camera by comparing the image with those of stars. It was confirmed that the RIS in orbit is working properly as a retroreflector.  相似文献   
978.
We assume that the electron (e ), neutrino (v e), and gauge bosons (W ±,Z 0) are composed of only two kinds of particles, an ultimate particleu at an infinite sublayer quark level and a chargeless fermiont, such thate =(u cp u cp l),V e =(u u cp l,W +=(u u ),W =(u cp u cp andZ 0=(u u cp . It is then shown thatCP is violated in weak interactions associated with these electron, neutrino, and gauge bosons.  相似文献   
979.
The lifetime of the first 2+ state in the nucleus 124Ba has been measured by γ-γ coincidence recoil-distance Doppler shift method. The 109Ag(19F, 4n)124Ba reaction at a beam energy of 75 MeV was employed to populate excited states in 124Ba. The mean lifetime was determined to be 275(12) ps using the differential decay curve method. The value of B(E2;01 +→ 21 +) for 124Ba deduced from the lifetime is in reasonable agreement with the prediction of the proton-neutron interacting boson model(IBM-2) without Pauli blocking effect. Received: 23 February 1998  相似文献   
980.
The chemical diffusion coefficient in a single crystal of magnetite was measured by observing the relaxation of deviations from stoichiometry responding to a stepwise change in oxygen partial pressure between 1300 and 1450°C. The chemical diffusion coefficient was proportional to (? Inδ?In po2)?1. The vacancy diffusion coefficient was calculated with the help of nonstoichiometric data and was found to be independent of the vacancy composition. The value of Dv was
Dv = (0.14 ± 0.08) exp (?(32,500 ± 1800)RT)cm2s?1
.  相似文献   
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