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排序方式: 共有347条查询结果,搜索用时 31 毫秒
111.
The effect of pressure on the electrical resistance of Fe90Zr10 and (Fe0.96Ni0.04)90Zr10 amorphous alloys has been investigated. The minimum point in the electrical resistance versus temperature curve shifts toward lower temperature range with increasing hydrostatic pressure, corresponding to the shift of the Curie temperature. The decrement of the electrical resistance below the Curie temperature Tc is about twice that above Tc, suggesting a large compressibility in the ferromagnetic state of the amorphous Invar alloys. 相似文献
112.
I. V. Bykov E. A. Gan’shina A. B. Granovsky V. S. Gushchin A. A. Kozlov T. Masumoto S. Ohnuma 《Physics of the Solid State》2005,47(2):281-286
The magnetorefractive effect and optical reflectivity are studied in granular Co-Al-O, Co-Si-O, and Co-Ti-O metal-insulator alloys exhibiting tunneling magnetoresistance for compositions close to the percolation threshold. The dependences of these effects on frequency, angle of incidence, and light polarization were measured. The experimental data obtained suggest that the major MRE mechanism in these systems is spin-dependent tunneling at optical frequencies. 相似文献
113.
114.
Dr. Kouta Sugikawa Tatsuya Kadota Dr. Kazuma Yasuhara Prof. Atsushi Ikeda 《Angewandte Chemie (International ed. in English)》2016,55(12):4059-4063
The behavior of self‐assembly processes of nanoscale particles on plasma membranes can reveal mechanisms of important biofunctions and/or intractable diseases. Self‐assembly of citrate‐coated gold nanoparticles (cAuNPs) on liposomes was investigated. The adsorbed cAuNPs were initially fixed on the liposome surfaces and did not self‐assemble below the phospholipid phase transition temperature (Tm). In contrast, anisotropic cAuNP self‐assembly was observed upon heating of the composite above the Tm, where the phospholipids became fluid. The number of self‐assembled NPs is conveniently controlled by the initial mixing ratio of cAuNPs and liposomes. Gold nanoparticle protecting agents strongly affected the self‐assembly process on the fluidic membrane. 相似文献
115.
Dissipative and Autonomous Square‐Wave Self‐Oscillation of a Macroscopic Hybrid Self‐Assembly under Continuous Light Irradiation 下载免费PDF全文
Tomonori Ikegami Dr. Yoshiyuki Kageyama Kazuma Obara Prof. Sadamu Takeda 《Angewandte Chemie (International ed. in English)》2016,55(29):8239-8243
Building a bottom‐up supramolecular system to perform continuously autonomous motions will pave the way for the next generation of biomimetic mechanical systems. In biological systems, hierarchical molecular synchronization underlies the generation of spatio‐temporal patterns with dissipative structures. However, it remains difficult to build such self‐organized working objects via artificial techniques. Herein, we show the first example of a square‐wave limit‐cycle self‐oscillatory motion of a noncovalent assembly of oleic acid and an azobenzene derivative. The assembly steadily flips under continuous blue‐light irradiation. Mechanical self‐oscillation is established by successively alternating photoisomerization processes and multi‐stable phase transitions. These results offer a fundamental strategy for creating a supramolecular motor that works progressively under the operation of molecule‐based machines. 相似文献
116.
Jackson TR Springall JS Rogalle D Masumoto N Ching Li H D'Hooge F Perera SP Jenkins AT James TD Fossey JS van den Elsen JM 《Electrophoresis》2008,29(20):4185-4191
The incorporation of specialised carbohydrate affinity ligand methacrylamido phenylboronic acid in polyacrylamide gels for fluorophore-assisted carbohydrate electrophoresis greatly improved the effective separation of saccharides that show similar mobilities in standard electrophoresis. Polyacrylamide gel electrophoresis using methacrylamido phenylboronic acid in low loading (typically 0.5-1% dry weight) was unequivocally shown to alter retention of labelled saccharides depending on their boronate affinity. While conventional fluorophore-assisted carbohydrate electrophoresis of 2-aminoacridone labelled glucose oligomers showed an inverted parabolic migration, an undesired trait of small oligosaccharides labelled with this neutral fluorophore, boron affinity saccharide electrophoresis separation of these carbohydrates completely restored their predicted running order, based on their charge/mass ratio, and resulted in improved separation of the analyte saccharides. These results exemplify boron affinity saccharide electrophoresis as an important new technique for analysing carbohydrates and sugar-containing molecules. 相似文献
117.
Kazuma Yasuhara Yoshihiro Sasaki Jun-ichi Kikuchi 《Colloid and polymer science》2008,286(14-15):1675-1680
An azobenzene-modified cholesterol was designed and synthesized for photo-induced domain transformation in lipid bilayer membranes. Upon UV-light irradiation, the cholesterol derivative changes the conformation through photoisomerization of the azobenzene moiety from trans- to cis-form. The photoisomerization effectively occurred both in liquid-ordered (Lo) and liquid-disordered (Ld) phases. Phase-contrast and fluorescence microscopic observation revealed that photoisomerization of the azobenzene-modified cholesterol induced the shape transformation of giant unilamellar vesicle (GUV) and the reorganization of Lo domain structure. Such a photo-induced transformation of lipid domain gave two different pathways dependent on the lipid composition of GUV; disappearance of the Lo domain or appearance of a small Ld domain with in the Lo domain. 相似文献
118.
Yousuke Yamaoka Motoki Ueda Tohru Yamashita Kazuma Shimoda Ken-ichi Yamada Kiyosei Takasu 《Tetrahedron letters》2017,58(30):2944-2947
Cyclic ketene silyl acetals were utilized for [2 + 2] cycloaddition with propiolates to prevent an undesired electrocyclic ring opening reaction. Trimethylaluminum catalyzed this cycloaddition to afford the cyclobutene derivatives in high yields. The advantage of this reaction was highlighted by the successful application of β-substituted propiolates to afford the multi-substituted cyclobutenes. Furthermore, we applied this methodology to the late stage functionalization of natural product artemisinin. 相似文献
119.
An optical scanning probe microscope, based on surface plasmon resonance (SPR) in the attenuated total reflection geometry, is shown to successfully image the polarization structures in self-assembled monolayers of hemicyanine adsorbed on a gold surface. Application of an ac field to the tip gives rise to the linear electro-optic effect in the monolayer just below the tip and the local change in the refractive index of the monolayer was detected via the ac component of the reflected light intensity, in which SPR-based detection intensifies the ac component. Polarization structures in a monolayer can be clearly imaged by this technique. 相似文献
120.
Kazuma Gotoh Hiroyuki Ishida 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(12):o500-o504
In the four compounds of chloranilic acid (2,5‐dichloro‐3,6‐dihydroxycyclohexa‐2,5‐diene‐1,4‐dione) with pyrrolidin‐2‐one and piperidin‐2‐one, namely, chloranilic acid–pyrrolidin‐2‐one (1/1), C6H2Cl2O4·C4H7NO, (I), chloranilic acid–pyrrolidin‐2‐one (1/2), C6H2Cl2O4·2C4H7NO, (II), chloranilic acid–piperidin‐2‐one (1/1), C6H2Cl2O4·C5H9NO, (III), and chloranilic acid–piperidin‐2‐one (1/2), C6H2Cl2O4·2C5H9NO, (IV), the shortest interactions between the two components are O—H...O hydrogen bonds, which act as the primary intermolecular interaction in the crystal structures. In (II), (III) and (IV), the chloranilic acid molecules lie about inversion centres. For (III), this necessitates the presence of two independent acid molecules. In (I), there are two formula units in the asymmetric unit. The O...O distances are 2.4728 (11) and 2.4978 (11) Å in (I), 2.5845 (11) Å in (II), 2.6223 (11) and 2.5909 (10) Å in (III), and 2.4484 (10) Å in (IV). In the hydrogen bond of (IV), the H atom is disordered over two positions with site occupancies of 0.44 (3) and 0.56 (3). This indicates that proton transfer between the acid and base has partly taken place to form ion pairs. In (I) and (II), N—H...O hydrogen bonds, the secondary intermolecular interactions, connect the pyrrolidin‐2‐one molecules into a dimer, while in (III) and (IV) these hydrogen bonds link the acid and base to afford three‐ and two‐dimensional hydrogen‐bonded networks, respectively. 相似文献