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81.
We propose a reactive ion etching (RIE) process of an L10-FePt film which is expected as one of the promising materials for the perpendicular magnetic recording media. The etching was carried out using an inductively coupled plasma (ICP) RIE system and an etching gas combination of CH4/O2/NH3 was employed. The L10-FePt films were deposited on (1 0 0)-oriented MgO substrates using a magnetron sputtering system. The etching masks of Ti were patterned on the FePt films lithographically. The etch rates of ∼16 and ∼0 nm/min were obtained for the FePt film and the Ti mask, respectively. The atomic force microscopy (AFM) analyses provided the average roughness (Ra) value of 0.95 nm for the etched FePt surface, that is, a very flat etched surface was obtained. Those results show that the highly selective RIE process of L10-FePt was successfully realized in the present study.  相似文献   
82.
83.
An asymmetric ac electric field with amplitudeE=10 V/μm gives rise to a matched rotation of the normal to the smectic layers, while a sinusoidal fieldE=1 V/μm is used to study the rotation in the method of modulation total internal reflection ellipsometry, which makes it possible to probe the region of a ferroelectric liquid crystal (FLC) next to the electrode (h≈0.7 μm). It is shown that the angle of rotation of the normal to the smectic layers near the surface of the electrode varies reversibly as a function of the polarity and number of electric pulses applied, just as in the interior region. The characteristic dynamic properties of thin layers of nematic liquid crystals, such as an anomalously long relaxation time and a high-frequency relaxation process, are observed in thin FLC layers.  相似文献   
84.
正Recent years have witnessed rapid progress in calculating parton distribution functions (PDFs), rather than just their moments, from lattice QCD [1-9]. The most remarkable aspect of such calculations is that one can connect appropriately chosen Euclidean correlation functions calculable on the lattice to PDFs through a perturbative matching relation. This can be understood in the framework of the large-momentum  相似文献   
85.
86.
We study a C -Liouville-integrable and analytic non-integrable Hamiltonian system. We will show that an irregular singular character plays a crucial role in the analytic non-integrability of the system. Partially supported by Grant-in-Aid for Scientific Research (No. 11640183), Ministry of Education, Science and Culture, Japan.  相似文献   
87.
This paper deals with the quasilinear degenerate Keller–Segel systems of parabolic–parabolic type in a ball of RN (N2). In the case of non-degenerate diffusion, Cie?lak–Stinner [3], [4] proved that if q>m+2N, where m denotes the intensity of diffusion and q denotes the nonlinearity, then there exist initial data such that the corresponding solution blows up in finite time. As to the case of degenerate diffusion, it is known that a solution blows up if q>m+2N (see Ishida–Yokota [13]); however, whether the blow-up time is finite or infinite has been unknown. This paper gives an answer to the unsolved problem. Indeed, the finite-time blow-up of energy solutions is established when q>m+2N.  相似文献   
88.
Satz 41 in Hasse's monograph [4] is modified because of the incorrectness of Satz 29. We investigate unit indices of imaginary abelian number fields of type (2,2) and (2,2, 2), some of which give counterexamples to Satz 41. We moreover give a relation between unit indices of certain imaginary fields of type (2,22) and those of their real cyclic subfields.  相似文献   
89.
Experimental infrared modulator elements have been fabricated utilizing the transient light scattering effect of ferroelectric liquid crystal with asymmetric waveform voltage drive. The new elements perform 80% modulation degrees at the 632.8nm. We have also achieved 30% modulation degrees in the 4 to 5µ m region where the strongest CO2 absorption bands exist. A new type of analyzer which monitors ambient air quality has been developed. This analyzer uses non-dispersive infrared absorption method and composes of a double-beam, a single detector and a pair of liquid crystal light modulator as the IR chopper. The detection has achieved 10ppm noise equivalent concentration.  相似文献   
90.
In 1982, S. Friedland proved that a bounded linear operator A on a Hilbert space is normal if and only if (αI + A + A*)2 ≧ AA* − A*A ≧ −(αI + A + A*)2 for all real α. And he conjectured the inequality (αI + A + A*)2 ≧ AA* − A*A for all real α will imply that A*A − AA* ≧ 0, i.e., A is hyponormal. But his conjecture is incorrect. In this note I’ll give a counter-example for his conjecture.  相似文献   
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