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排序方式: 共有365条查询结果,搜索用时 15 毫秒
91.
Yuichi Miura Tetsumasa Nakayasu Takayoshi Mamiya Hideharu Kato 《Journal of Low Temperature Physics》1998,110(1-2):115-119
We have measured the shear modulus of bcc solid
3
He at 827 Hz using the high- Q torsional oscillator technique. We observed a decrease in the shear modulus from the low-temperature value G0
to about 0.4G0
at a molar volume of 24.80 cm
3/mole and to 0.6G0
at 24.32 cm
3/mole near the melting point. The reduction of an effective shear modulus is explained by the dislocation theory of Granato and Lücke. 相似文献
92.
Okura Fumio Akaguma Takayuki Sato Tomokazu Yokoya Naokazu 《Multimedia Tools and Applications》2017,76(2):2671-2695
Multimedia Tools and Applications - Indirect augmented reality (IAR) employs a unique approach to achieve high-quality synthesis of the real world and the virtual world, unlike traditional... 相似文献
93.
Naka H Vang le V Inomata S Ando T Kimura T Honda H Tsuchida K Sakurai H 《Journal of chemical ecology》2003,29(11):2447-2459
Three electroantennogram (EAG)-active components were detected by gas chromatography coupled to an electroantennographic detector (GC–EAD) analysis of a hexane extract of the pheromone glands of the persimmon fruit moth, Stathmopoda masinissa. These compounds were identified as (4E,6Z)-4,6-hexadecadienal (E4,Z6-16:Ald) and the corresponding acetate (E4,Z6-16: OAc) and alcohol (E4,Z6-16:OH) by mass spectral, GC retention time (RT), and microchemical test data. The characteristic base peak of the aldehyde at m/z 84 provided a crucial piece of information suggesting the possibility of a 4,6-diene structure. The (4E,6Z)-isomer elicited the strongest EAG responses among the four geometrical isomers of each synthetic 4,6-hexadecadienyl compound. In a laboratory bioassay, only E4,Z6-16:OAc elicited male moth behavioral activity significantly different from the control; the activity of the acetate was not affected by addition of the aldehyde and alcohol. A preliminary field trial confirmed that E4,Z6-16:OAc as a single component attracted male moths. The possible roles of E4,Z6-16:Ald and E4,Z6-16:OH as components of lures for field use remain to be determined. 相似文献
94.
Toyohiko Yano Masanori Ikari Takayoshi Iseki Eugene H. Farnum Frank W. Clinard Jr. T. E. Mitchell 《Journal of the American Ceramic Society》1995,78(6):1469-1474
MgO·3Al2 O3 single crystals were irradiated with neutron fluences of 8.3 × 1022 n/m2 at 100°C and 2.4 × 1024 n/m2 at 470°C ( E > 1.0 MeV) in the Japan Materials Testing Reactor. The Knoop microhardness of several orientations on the (100) plane of both the irradiated and unirradiated crystals were measured with different indentation loads. The change in hardness profile of the crystals was almost the same after the two irradiation conditions. The hardness increased by 4–15% because of the irradiations depending on the crystallographic orientation, the larger change being observed at orientations between the (001) and (011) directions. While both the {111} and {110} slip systems are simultaneously active in the unirradiated MgO·3Al2 O3 , the {111} system may be the dominant slip system in the neutron-irradiated crystals. It is concluded that the restriction of the {110} slip system is caused by irradiation-induced interstitial ions. 相似文献
95.
Keiji Yada Hideki Masaoka Yutaka Shoji Takayoshi Tanji 《Microscopy research and technique》1989,12(3):252-261
Thermionic emission properties of several kinds of refractory carbides, nitrides, and borides of the transition metals in the form of powder were investigated with a newly developed measuring device and evaluated by the figure of merit defined as the ratio of the effective work function to the working temperature at which the vapor pressure becomes 1 × 10?5 Torr. There are several materials whose thermionic emission properties are better than those of tungsten or compatible to those of tungsten among the carbides and borides, such as TaC, HfC, ZrC, LaB6, and CeB6, as judged by the figure of merit. New preparation methods for carburization, nitriding, and boriding of the wires of matrix metals and alloys were successfully developed for using these materials as the cathode of the electron microscope. Other necessary techniques such as spot welding and electrolytic etching were also developed. From the brightness characteristics, it was found that some of carbides, carbide solid solutions, and borides such as HfC, ZrC (Ta0.8–0.7Hf0.2–0.3)C, TaB2, and HfB2 are very good emitters comparable to LaB6. It is emphasized that the work functions of the carbide-solid solutions (Ta0.8Hf0.2)C and (Ta0.7Hf0.3)C, which have low rates of evaporation at high temperature, show no remarkable rise as compared with that of HfC, so that their figures of merit are better than that of HfC. Feasibility of providing good cathodes with HfC and (Ta0.8Hf0.2)C tips was demonstrated by taking high-resolution electron micrographs. 相似文献
96.
Simulation of a hollow cone-shaped probe in aberration-corrected STEM for high-resolution tomography
Tadahiro Kawasaki Takaomi Matsutani Takashi Ikuta Mikio Ichihashi Takayoshi Tanji 《Ultramicroscopy》2010
In a simulation study, we found that focal depth extension using a hollow cone-shaped probe with an annular aperture is useful for three-dimension (3D) tomography of aberration-corrected scanning transmission electron microscopy (STEM). Our calculations showed that, for 200 kV STEM, a sub-angstrom sized probe could extend the focal depth from a few to more than several tens nm. We also examined the influence of obstructing bridges, including actual fabricated annular apertures, on focused probe intensity distribution. We found that, to avoid any distortion of probe intensity, the width of the bridges should be narrow. Quantitative evaluation showed that the ratio of obstructing area of the bridges to the area of the annular slit should be less than 0.11. 相似文献
97.
Md. Imranul Hoq Takayoshi Aoki Hisham R. Ibrahim 《Food research international (Ottawa, Ont.)》2009,42(2):298-306
The oxidative stability of bioactive proteins is a critical issue in the food and drug development process. Recently, we explored a superior and multi-faceted antimicrobial compound by coupling the lytic enzyme lysozyme (LZ) to a phenolic antibiotic triclosan (TCS) via electrostatic and hydrophobic condensations at alkaline pH. To explore the candidacy of LZ–TCS complex (T–LZ) in food systems, its stability against photooxidative damage has been investigated in this study using riboflavin (RF) as a sensitizer. Electrophoretic and Tryptophan (Trp) fluorescence spectra revealed significant protection of LZ conformation in T–LZ complexes against mild or excessive photooxidative treatment using equivalent to variable mole ratios of RF over LZ. The promoted muramidase activity of T–LZ complexes, reported in our previous study, was markedly protected against both mild and excessive photooxidative treatments. However, LZ alone exhibited polymerization, fragmentation and quenching of Trp fluorescence upon photooxidation reaction. This suggests that in the complexes TCS binds with the tryptophan residues at LZ active site and thereby inhibits oxidation. Further, the complex retained its strong antimicrobial activity against several Gram-positive and Gram-negative bacteria even upon photooxidative treatment while causing a dramatic reduction in antimicrobial activity of TCS alone. The results indicate that accommodation of the TCS in the hydrophobic pocket of LZ does not only protect LZ from oxidation-induced loss of biological activities but also protect phenolic antimicrobial TCS from oxidative damage until its delivery to the bacterial cell. The finding, therefore, offers a new strategy in designing an oxidation-resistant microbicidal phenol–protein macromolecule with potential use in food and drug systems. 相似文献
98.
99.
Can-Peng Li Yoko Hayashi Hirofumi Enomoto Fangyu Hu Yoriko Sawano Masaru Tanokura Takayoshi Aoki 《Food chemistry》2009
Various proteins and dextrin were phosphorylated by dry-heating in the presence of pyrophosphate, and phosphate bonds characterised. The basic proteins were more highly phosphorylated than acidic proteins by dry-heating in the presence of pyrophosphate. The phosphorylated poly-l-lysine hydrobromide (PP-PLy) and lysozyme (PP-Lz) were more highly dephosphorylated than phosphorylated dextrin and ovalbumin (PP-OVA) by phosphatases, and the dephosphorylation of PP-PLy was much higher than that of PP-Lz. The phosphate bonds in all phosphorylated samples were stable during heating at 120 °C. The 31P NMR spectral data suggested that different types of phosphate bonds were introduced, and the N–P bond was suggested in PP-PLy. Some phosphorylated tryptic peptides from PP-Lz and PP-OVA were detected by mass spectrometry analysis. Furthermore, the introduced phosphate linkages in peptides from PP-Lz and PP-OVA were identified. 相似文献
100.
Li Zhao Tokuhiro Chano Shigehiro Morikawa Yukie Saito Akihiko Shiino Sawako Shimizu Takuro Maeda Takayoshi Irie Shuji Aonuma Hidetoshi Okabe Takahide Kimura Toshiro Inubushi Naoki Komatsu 《Advanced functional materials》2012,22(24):5107-5117
For biomedical application of nanoparticles, the surface chemical functionality is very important to impart additional functions, such as solubility and stability in a physiological environment, and targeting specificity as an imaging probe and a drug carrier. Although polyethylene glycol (PEG) has been used extensively, here, it is proposed that hyperbranched polyglycerol (PG) is a good or even better alternative to PEG. Superparamagnetic iron oxide nanoparticles (SPIONs) prepared using a polyol method are directly functionalized with PG through ring‐opening polymerization of glycidol. The resulting SPION‐PG is highly soluble in pure water (>40 mg mL?1) and in a phosphate buffer solution (>25 mg mL?1). Such high solubility enables separation of SPION‐PG according to size using size exclusion chromatography (SEC). The size‐separated SPION‐PG shows a gradual increase in transverse relaxivity (r2) with increasing particle size. For biological application, SPION‐PG is functionalized through multistep organic transformations (–OH → –OTs (tosylate) → –N3 → –RGD) including click chemistry as a key step to impart targeting specificity by immobilization of cyclic RGD peptide (Arg‐Gly‐Asp‐D ‐Tyr‐Lys) on the surface. The targeting effect is demonstrated by the cell experiments; SPION‐PG‐RGD is taken up by the cells overexpressing αvβ3‐integrin such as U87MG and A549. 相似文献