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排序方式: 共有1337条查询结果,搜索用时 8 毫秒
31.
Chiral diporphyrin nanotweezers 1 consisting of two chiral porphyrins with N-substituted 3,6-carbazolylene in between have been studied for the separation of single-walled carbon nanotubes (SWNTs). As compared to the analogous nanotweezers 2 without an N-substitutent, nanotweezers 1 with the N-octylcarbazolylene spacer exhibit much higher extraction ability and better selectivity for SWNTs. A narrower diameter range of SWNTs, from 0.88 to 0.92 nm, was selectively extracted with nanotweezers 1. In addition, only (7,6)-SWNTs of 0.90 nm diameter were optically enriched through extraction with 1, while SWNTs extracted with 2 showed lower optical purity of (7,6)-SWNTs. These enhanced extraction and discrimination abilities of 1 can be attributed to the formation of a more stable SWNT complex of 1 than of 2 in methanol. 相似文献
32.
Takayama H Takahashi S Moriya T Osada H Iwabuchi Y Kanoh N 《Chembiochem : a European journal of chemical biology》2011,12(18):2748-2752
Seeing below the surface: A small-molecule droplet array platform on an NADH-immobilized solid surface and a biotinylated acetophenone derivative were developed to identify the substrate candidates for soluble P450 enzymes of interest. This methodology is thought to be easily applicable to other class I P450 systems, including those that use NADPH as cofactor. 相似文献
33.
Naoki Yasumaru Kenzo MiyazakiJunsuke Kiuchi Eisuke Sentoku 《Diamond and Related Materials》2011,20(4):542-545
This paper reports macro and micro frictional properties of DLC, TiN, CrN films and GC substrate of which surfaces are nanostructured with femtosecond (fs) laser pulses. The friction coefficient μ of the nanostructured surface was measured at a usual load with a ball-on-disk friction test machine. The results have shown that carbon materials of DLC and GC provide lower values of μ than TiN and CrN, and μ of DLC and TiN measured with a hardened steel ball decreases with an increase of the laser pulse energy. On the other hand, μ of nanostructured surfaces of thin films monotonously increases with an increase in laser pulse energy, which was measured with a micro-scratch test at an ultralight load of 1.5 mN utilizing a diamond tip. The friction coefficient of the GC substrate irradiated at a low fluence around the ablation threshold has shown a lower value than that of the non-irradiated surface. 相似文献
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35.
Low-resistivity indium tin oxide [ITO] film was successfully deposited on oxygen plasma-treated polyethylene terephthalate [PET] surfaces at room temperature. X-ray diffraction [XRD] measurements demonstrated that the film deposited on the PET surface that had not been treated with oxygen plasma had an amorphous structure. In contrast, after the low-power oxygen plasma treatment of the PET surface, the ITO film deposited on the PET surface had a poly-crystalline structure due to interactions between electric dipoles on the PET surface and electric dipoles in the ITO film. The minimum resistivity of the poly-crystalline ITO was about 3.6 times lower than that of the amorphous ITO film. In addition, we found that the resistivity of ITO film is proportional to the intensity of the (400) line in the film's XRD spectra. 相似文献
36.
Yukihide Shiraishi Shunsuke Kobayashi Naoki Toshima 《Israel journal of chemistry》2012,52(10):908-916
Metal nanoparticles are now creating a new class of materials that are different from either conventional bulk materials or atoms, giving one of the smallest building blocks of matter. Metal nanoparticles have various properties based on high surface area and quantum size effects. Here we focus on the application of metal nanoparticles to liquid crystal displays, which is providing a new field in science and technology. The doping of nanoparticles into liquid crystal materials induces the modification of almost all of the physical properties of the liquid crystal, causing a reduction in the response time of liquid crystal displays. These techniques may be an alternative approach for improving the properties of liquid crystals other than chemical synthesis. 相似文献
37.
Wu-Bian Tian Hideki KitaHideki Hyuga Naoki Kondo 《Journal of the European Ceramic Society》2012,32(1):149-156
SiC ceramics were successfully joined by Al infiltrated TiC tapes at 900-1100 °C for 0.5-2 h in vacuum. Phase constituents, microstructure and mechanical strength of the prepared SiC joints were characterized. The prepared SiC joints display dense interlayer and crack-free interface. The interlayer primarily consists of TiC and Al phases, together with small amount of TiAl3 and trace of Al4C3. With increasing the joining temperature or time, the interface layer either thickens or grows to multiple layers. The bending strengths of the SiC joints are higher than 190 MPa as bonded at present conditions, and are closely related with the property of interface and interlayer. 相似文献
38.
Tomonori Waku Ayane Kasai Akio Kobori Naoki Tanaka 《International journal of molecular sciences》2020,21(24)
Self-assembled peptide nanofibers (NFs) obtained from β-sheet peptides conjugated with drugs, including antigenic peptides, have recently attracted significant attention. However, extensive studies on the interactions of β-sheet peptide NFs with model cell membranes have not been reported. In this study, we investigated the interactions between three types of NFs, composed of PEG-peptide conjugates with different ethylene glycol (EG) lengths (6-, 12- and 24-mer), and dipalmitoylphosphatidylcholine (DPPC) Langmuir membranes. When increasing the EG chain length, those interactions significantly decreased considering measurements in the presence of the NFs of: (i) changes in surface pressure of the DPPC Langmuir monolayers and (ii) surface pressure–area (π–A) compression isotherms of DPPC. Because the observed trend was similar to the EG length dependency with regard to cellular association and cytotoxicity of the NFs that was reported previously, the interaction of NFs with phospholipid membranes represented a crucial factor to determine the cellular association and toxicity of the NFs. In contrast to NFs, no changes were observed with varying EG chain length on the interaction of the building block peptide with the DPPC membrane. The results obtained herein can provide a design guideline on the formulation of β-sheet peptide NFs, which may broaden its potential. 相似文献
39.
A discrete variational-Xα (DV-Xα) method was applied to elucidate the formation of C-O-Si bridging bonds, produced when a silanol group of SiO2 comes close enough to react with a carboxyl group of indomethacin (IM). A decrease in the coordination number (CN) of oxygen atoms per silicon atom at the SiO2 surface increased the net charge (NC) of the silanolic hydrogen atom and decreased the bond overlap population (BOP) between the silanolic oxygen and hydrogen atoms. These changes favored the formation and stabilization of C-O-Si bridging bonds with simultaneous dehydration. The computational results agreed well with our previous experimental study of a ground indomethacin-SiO2 mixture to obtain a better solid dispersion of the drug. 相似文献
40.