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排序方式: 共有622条查询结果,搜索用时 15 毫秒
71.
Lithium phosphorus oxynitride (LiPON) films were prepared by radio frequency magnetron sputtering. In order to control the atomic composition of the films, a mixture of Li3PO4 and Li2O powders was used as the sputtering target. The ionic conductivity of the films showed a maximum (6.4 × 10− 6 S/cm) when the molar ratio of Li3PO4 to Li2O in the target was 1:2. The films formed from a target not containing Li2O showed good durability in air at the expense of slightly poorer ionic conductivity. This is probably due to the amount of Li in the film being significantly less which effectively suppressed absorption of CO2 in air. 相似文献
72.
Fu-Long Sun Li-Yin Gao Zhi-Quan Liu Hao Zhang Tohru Sugahara Shijo Nagao Katsuaki Suganuma 《材料科学技术学报》2018,34(10):1885-1890
Homogeneous columnar Cu film with fully embedded nanotwins was successfully fabricated on Ti/Cu seed layer on silicon wafer. The nanotwins with thickness of tens of nanometers are generally parallel to the silicon surface, showing a strong (111) preferred orientation. The acid concentration was found to be important in influencing the formation of nanoscale twins. By adjusting the acid concentration, the nanotwins can be induced from the top columnar grain to middle columnar grain and reach the bottom equiaxed grain, and a microstructural transformation model was given. A theory focusing on the cathode overpotential was proposed to reveal the effect of acid concentration on the growth mechanism of nanoscale twins. An appropriate adsorption proportion of hydrogen on cathode (acid concentration 17 ml L?1) could increase the overpotential which supplies adequate nucleation energy for nanoscale twins formation. 相似文献
73.
Minsu Kim Ryo Ito Sangwook Kim Gopal Prasad Khanal Ichiro Fujii Tohru S. Suzuki Tetsuo Uchikoshi Chikako Moriyoshi Yoshiro Kuroiwa Satoshi Wada 《Journal of Materials Science》2018,53(4):2396-2404
Electrophoretic deposition (EPD) process has certain advantages such as it can be applied for a mass production and also can be combined with magnetic crystal alignment technique. In this work, we prepared lead-free 85(Bi0.5Na0.5)TiO3–15BaTiO3 (85BNT–15BT) piezoelectric ceramics by conventional uniaxial pressing and EPD process. Various conditions were optimized such as suspension media, applied electrical field, and deposition time in order to yield dense green ceramics of 85BNT–15BT composition using EPD process. 85BNT–15BT ceramics prepared using EPD process revealed the Curie temperature of about 250 °C, coercive field of about 30 kV/cm, and piezoelectric constant (d 33) of 75 pC/N. The EPD-processed samples exhibited structural and electrical properties similar to that of the conventionally processed one suggesting the successful fabrication of 85BNT–15BT piezoelectric ceramics by EPD method without composition deviation. This study lays a foundation on the fabrication of Bi-based lead-free piezoelectric ceramics by an alternative route other than the conventionally practiced solid-state reaction method maintaining the similar chemical composition, moreover, leaving a large space to explore more in the future. 相似文献
74.
Awane T Kimura T Nishida K Ishikawa N Tanuma S Nakamura M 《Analytical chemistry》2003,75(15):3831-3836
Grazing exit electron probe microanalysis (GE-EPMA) is a new method of EPMA in which characteristic X-rays emitted from only near-surface regions of a specimen are detected at extremely low exit angles near 0 degrees (the grazing exit condition). This technique requires the analytical objects exist on a flat surface. Therefore, the GE-EPMA analysis has been used only for the analysis of particles or a thin film on a flat substrate so that there were only few applications for practical analysis. As a new application, we have carried out GE-EPMA analysis of approximately 0.2-microm inclusions on stainless steel, which appeared to be a projection on the specimen surface with chemical etching. The GE-EPMA quantitative results were in excellent agreement with those of inclusions that were extracted from the stainless steel and analyzed by EPMA with conventional exit condition (30 degrees). This method could be, therefore, applied to the analysis of the submicrometer inclusion in a wide variety of metallic materials if the inclusion appears to be a projection with chemical etching treatment. 相似文献
75.
Takano Y Koizumi M Takarada R Kamimura MT Czerminski R Koike T 《Journal of molecular graphics & modelling》2003,22(2):105-114
We have investigated a new approach to efficiently find a novel inhibitor against a serine protease (i.e. an activated coagulation factor X, FXa) by using de novo design programs and the X-ray crystal structure of the target enzyme. FXa is a coagulant enzyme that generates thrombin (a serine protease) and participates in both intrinsic and extrinsic coagulation pathways. We adopted multiple copy simultaneous search (MCSS) and CAVEAT linker search techniques, which disclosed a novel FXa inhibitor (T01312) consisting of two binding moieties (the benzamidinyl and adamantyl groups) and a linker unit (the carboxybenzylamine group). The inhibitory activity of T01312 against FXa was determined to be a small K(i)-value of 48nM, which is two orders of magnitude smaller than that against thrombin. An X-ray crystal analysis of T01312 complexed with trypsin (an analogue of FXa) and docking studies of T01312 with trypsin and FXa showed that: (i) the benzamidinyl group is a predominant binding moiety in the anionic pocket (S1 site) with an asparatic acid residue; (ii) a hydrophobic pocket (S4 site) is the binding site of the adamantyl group; (iii) the carboxylate group of the linker contributes to the selectivity for FXa against thrombin. Thus, the combination of the knowledge of the X-ray crystal structure of the target molecule with MCSS and CAVEAT linker search techniques proved to be an effective hit-finding method that does not require the screening of huge compound libraries. 相似文献
76.
In order to study the contrast difference between scanning ion microscopes (SIM) and scanning electron microscopes (SEM), the depth and lateral distributions of secondary electrons escaped from surfaces of 17 metals with atomic numbers, Z2, of 4-79 were calculated for bombardment with 30 keV Ga ions and for 10 keV electrons. For both projectiles, the excitation depth generally decreased with increasing Z2, while showing the same periodic change as the secondary-electron yield. However, an opposite trend in Z2 dependence between the Ga ion and electron bombardments was calculated with the lateral distribution of secondary electrons escaped from the surface. Except for low Z2 metals, the lateral distribution, which is much narrower for 30 keV Ga ions than for 10 keV electrons, indicates that the spatial resolution of the secondary-electron images is better for SIM than for SEM, if zero-sized probe beams are assumed. Furthermore, the present calculation reveals important effects of electron excitation by recoiled material atoms and reflected electrons on the lateral distribution, as well as the secondary-electron yield, for the Ga ion and electron bombardments, respectively. 相似文献
77.
A new beta-agarase was purified from an agarolytic bacterium, Bacillus sp. MK03. The enzyme was purified 129-fold from the culture supernatant by ammonium sulfate precipitation, anion exchange and gel filtration column chromatographic methods. The purified enzyme appeared as a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Estimation of the molecular mass by SDS-PAGE and gel filtration gave values of 92 kDa and 113 kDa, respectively. The N-terminal amino acid sequence of the enzyme showed no homology to those of other known agarases. The optimum pH and temperature for this enzyme were 7.6 and 40 degrees C, respectively. The predominant hydrolysis product of agarose by this enzyme was neoagarotetraose, indicating the cleavage of beta-1,4 linkage. This enzyme could hydrolyze neoagarohexaose to produce neoagarotetraose and neoagarobiose; it could not hydrolyze these products. The enzyme digested agarose by endo-type hydrolysis. 相似文献
78.
Syoji Kobashi Yuji Fujiki Mieko Matsui Noriko Inoue Katsuya Kondo Yutaka Hata Tohru Sawada 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(1):74-86
Measurement of volume and surface area of the frontal, parietal, temporal and occipital lobes from magnetic resonance (MR) images shows promise as a method for use in diagnosis of dementia. This article presents a novel computer-aided system for automatically segmenting the cerebral lobes from 3T human brain MR images. Until now, the anatomical definition of cerebral lobes on the cerebral cortex is somewhat vague for use in automatic delineation of boundary lines, and there is no definition of cerebral lobes in the interior of the cerebrum. Therefore, we have developed a new method for defining cerebral lobes on the cerebral cortex and in the interior of the cerebrum. The proposed method determines the boundaries between the lobes by deforming initial surfaces. The initial surfaces are automatically determined based on user-given landmarks. They are smoothed and deformed so that the deforming boundaries run along the hourglass portion of the three-dimensional shape of the cerebrum with fuzzy rule-based active contour and surface models. The cerebrum is divided into the cerebral lobes according to the boundaries determined using this method. The reproducibility of our system with a given subject was assessed by examining the variability of volume and surface area in three healthy subjects, with measurements performed by three beginners and one expert user. The experimental results show that our system segments the cerebral lobes with high reproducibility. 相似文献
79.
Kenji Murao Tohru Kohda 《International Journal of Circuit Theory and Applications》1994,22(3):221-232
A simple switched capacitor (SC) circuit is given which realizes a one-dimensional discrete dynamical system Xn+1 = Xn + uxz generating intermittent chaos with a 1/f-shaped power spectrum. an integrated circuit with a pair of logarithmic and antilogarithmic amplifiters can easily realize the power-law term xz which plays a key role in generating l/fnoise. an inevitable small offset voltage ? in the SC circuit governs the cut-off frequency of 1/f noise, and when the dynamical system is modified by introducing an effective ?, the ‘indirect method’ enables us to get the precise power spectrum in the modified system. 相似文献
80.
Field‐Effect Transistors: Integration of Organic Electrochemical and Field‐Effect Transistors for Ultraflexible,High Temporal Resolution Electrophysiology Arrays (Adv. Mater. 44/2016) 下载免费PDF全文