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181.
K. Okamoto 《Solid-state electronics》1974,17(11):1155-1161
The photocurrent of a p-channel gate-controlled MOS diode, which is induced within a field-induced junction (FI junction) and flows into drain circuits through an inversion layer, was measured. The lateral potential drop in the channel gives rise to narrowing of the depletion layer, so that the photocurrent begins to saturate for a small gate voltage or strong illumination. The spectral dependence of the photocurrent shows that the photosensitivity of the FI junction is superior to that of a PN junction in the short wavelength region because incident light can be introduced directly into the depletion layer of the FI junction. Electron excitations related to interface states are also observed in the spectral photoresponses of the samples prepared by the wet oxidation and the level is found at 0·11 eV above the valence band. 相似文献
182.
Eiichiro Fujisaki Tatsuaki Okamoto David Pointcheval Jacques Stern 《Journal of Cryptology》2004,17(2):81-104
Recently Victor Shoup noted that there is a gap in the widely believed security
result of OAEP against adaptive chosen-ciphertext attacks. Moreover, he showed
that, presumably, OAEP cannot be proven secure from the one-wayness of the underlying
trapdoor permutation. This paper establishes another result on the security of OAEP.
It proves that OAEP offers semantic security against adaptive chosen-ciphertext attacks,
in the random oracle model, under the partial-domain one-wayness of the underlying
permutation. Therefore, this uses a formally stronger assumption. Nevertheless, since
partial-domain one-wayness of the RSA function is equivalent to its (full-domain) onewayness,
it follows that the security of RSA-OAEP can actually be proven under the
sole RSA assumption, although the reduction is not tight. 相似文献
183.
A formulation for calculating the optical second-harmonic power based on the Cerenkov-radiation-type phase matching is derived for a crystal-cored fiber. The prerequisite condition for high efficiency is expressed by a simple relation by use of the refractive indices of a core crystal, a core radius, and a fundamental wavelength. An organic crystal-cored fiber is designed and practically fabricated by the guiding principle derived here. A blue second-harmonic wave of 1.4 mW is obtained from a 1-mm-long fiber by use of a 60-mW semiconductor laser, and the second-harmonic intensity agrees well with the prediction. Degradation of the organic core crystal caused by the generated blue wave is observed, and the lifetime of the device is evaluated. 相似文献
184.
185.
Polarisation characteristics in long single-mode fibres are investigated. Single-mode fibres used in the experiment have been fabricated by the v.a.d. (vapour-phase axial deposition) method. It was shown from the measurements on a 21 km single-span v.a.d. fibre that the state of polarisation of the incident light beam can be maintained over a long length when the incident plane of polarisation coincides with the major or minor axis of the single-mode optical fibre. 相似文献
186.
187.
Okamoto K 《The Review of scientific instruments》1980,51(3):302
A method for measuring the thickness of a very thin oxide layer by secondary electron emission is described. The secondary electron signals are measured for an oxide-covered silicon surface and a reference surface by using the line mode of scanning electron microscope. Then, their ratio correlates well with the thickness of oxide layer, and it is demonstrated that the thickness of an oxide layer can be obtained by measuring the ratio gamma. At the beam energy of 2 keV, the measurable thickness lies within the range of 15-150 A. The lower limit is due to the natural oxide remaining on the reference-silicon surface and the upper limit to charging effects of oxide layers. A remarkable feature of this method is that an oxide thickness localized in a very small area is measurable, and the measurement is carried out for an oxide deposided in 0.1-mm-wide ditches. 相似文献
188.
Our continuing research on the preparation, characterization, materials properties, and biodegradability of polylactide (PLA)/organically modified layered silicate (OMLS) nanocomposites has yielded results on PLA/montmorillonite nanocomposites. Montmorillonite (mmt) modified with dimethyldioctadecylammonium cation was used as an OMLS for nanocomposite preparation. The internal structure of nanocomposites on the nanometer scale was established with the use of wide-angle X-ray diffraction patterns and transmission electron micrographic observation. All nanocomposites exhibited significant improvement in crystallization behavior, mechanical properties, flexural properties, heat distortion temperature, and O2 gas permeability when compared with pure PLA. 相似文献
189.
Hideki Ono-Nakazato Kenji Taguchi Tateo Usui Keishi Tamura Yuuji Tomatsu 《Metallurgical and Materials Transactions B》2001,32(6):1113-1118
The standard Gibbs energies of formation of Cr2N and CrN have been measured by an equilibration technique and by using thermogravimetry and differential thermal analysis
(TG-DTA) at temperatures ranging from 1232 to 1523 K. The results are expressed as follows:
The standard Gibbs energies of formation of Cr2N and CrN determined by the present work are more negative than the values in the JANAF Tables by about 14 and 5 kJ/mol, respectively,
in the measured temperature range. 相似文献
190.
Organometallic Bonding in an Ullmann‐Type On‐Surface Chemical Reaction Studied by High‐Resolution Atomic Force Microscopy
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Shigeki Kawai Ali Sadeghi Toshihiro Okamoto Chikahiko Mitsui Rémy Pawlak Tobias Meier Jun Takeya Stefan Goedecker Ernst Meyer 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(38):5303-5311
The on‐surface Ullmann‐type chemical reaction synthesizes polymers by linking carbons of adjacent molecules on solid surfaces. Although an organometallic compound is recently identified as the reaction intermediate, little is known about the detailed structure of the bonded organometallic species and its influence on the molecule and the reaction. Herein atomic force microscopy at low temperature is used to study the reaction with 3,9‐diiododinaphtho[2,3‐b:2′,3′‐d]thiophene (I‐DNT‐VW), which is polymerized on Ag(111) in vacuum. Thermally sublimated I‐DNT‐VW picks up a Ag surface atom, forming a C? Ag bond at one end after removing an iodine. The C? Ag bond is usually short‐lived, and a C? Ag? C organometallic bond immediately forms with an adjacent molecule. The existence of the bonded Ag atoms strongly affects the bending angle and adsorption height of the molecular unit. Density functional theory calculations reveal the bending mechanism, which reveals that charge from the terminus of the molecule is transferred via the Ag atom into the organometallic bond and strengths the local adsorption to the substrate. Such deformations vanish when the Ag atoms are removed by annealing and C? C bonds are established. 相似文献