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61.
Morphologically novel tungsten nanorods (WNRs) with the co-existence of two crystalline phases, α-W (thermodynamically stable) and β-W, were fabricated by glancing angle RF magnetron sputtering technique under various Ar pressures and flow rates. For these nanorods, a significant variation in their morphology and surface roughness was observed. These structures could be useful in a wide range of applications such as field emission, robust superhydrophobic coatings, energy, and medicine. 相似文献
62.
Takayuki Tanaka Kentaro Sano Masafumi Ando Ami Sumiya Hidetaka Sawada Fumio Hosokawa Eiji Okunishi Yukihito Kondo Kunio Takayanagi 《Surface science》2010,604(23-24):L75-L78
In-situ gas-injection transmission electron microscopy revealed that a pillar grew at the edge of the interface of a gold nanoparticle and a TiO2 substrate during exposure to O2 gas at 100 Pa. The pillar was found to have a titanium-deficient chemical composition of Ti1 ? xO2 (x > 0) by electron energy loss spectroscopy (EELS). The spectra showed a chemical shift of oxygen and titanium ions to have ionic states of Ti3+ and Oy? (y < 3/2). The formation of the Ti1 ? xO2 at the contact edge of gold–Ti1 ? xO2 interface is discussed from the perspective of an O2 affinity, which plays an important role in CO oxidation process of supported gold particle. 相似文献
63.
Matsuda R Yoshioka Y Akiyama H Aburatani K Watanabe Y Matsumoto T Morishita N Sato H Mishima T Gamo R Kihira Y Maitani T 《Journal of AOAC International》2006,89(6):1600-1608
The labeling of 5 major allergenic ingredients (egg, milk, wheat, buckwheat, and peanut) is mandatory in Japan, and 2 series of enzyme-linked immunosorbent assay (ELISA) kits have been established as official screening methods. However, these official methods have not provided the necessary sensitivity, due in part to poor extraction efficiency. To address this need, 2 novel ELISA kits have been developed: the FASTKIT ELISA Ver. II Series and the FASPEK Allergenic Substances Detection Kit. The new kit systems use an improved extraction buffer that can extract insoluble proteins produced by processing and feature new antibodies that bind to the denatured proteins extracted with the new extraction buffer. The analytical performances of the 2 new ELISA kit series were evaluated in an interlaboratory study. Ten laboratories participated in the study and determined the major allergenic ingredients contained in 5 types of model processed food. The 2 ELISAs displayed fairly good reproducibility and sufficient recovery. 相似文献
64.
65.
Hirashita T Kamei T Satake M Horie T Shimizu H Araki S 《Organic & biomolecular chemistry》2003,1(21):3799-3803
Diastereoselective couplings of salicylaldehyde, anisaldehyde and 2-pyridylaldehyde with crotyl- and cinnamylindium reagents were studied. The syl/anti selectivity was found to depend largely on the ligands on the indium atom of the allylic indium reagents. A syn-selective cinnamylation of salicylaldehyde was realized by the combination of cinnamyl acetate and indium(I) iodide, whereas an anti-selective coupling with salicylaldehyde was achieved by the indium trichloride/aluminium-mediated cinnamylation. 相似文献
66.
Shiigi H Yamamoto Y Yakabe H Tokonami S Nagaoka T 《Chemical communications (Cambridge, England)》2003,(9):1038-1039
Gold nanoparticles, modified with alkyl thiol, formed a film on polystyrene substrate, and it was found that the deposited film drastically changes its conductivity and hydrophobicity, depending on the alkyl chain length of the thiol used. 相似文献
67.
Castro-Rodriguez I Nakai H Gantzel P Zakharov LN Rheingold AL Meyer K 《Journal of the American Chemical Society》2003,125(51):15734-15735
A series of five uranium-alkane complexes of the general formula [(ArO)3tacn)U(alkane)].(cy-alkane) has been synthesized and crystallographically characterized. In all cases, X-ray diffraction studies revealed a pseudo-six-coordinate trivalent uranium core structure, [(ArO)3tacn)U], with a coordinated alkane ligand at the axial position. The average U-C bond distance to the bound alkane was determined to be 3.798 A, which is considerably shorter than the sum of the van der Waals radii of the U atom and a CH2 or CH3 unit (3.9 A). In all complexes, the alkane is coordinated in an eta2-H,C fashion. 相似文献
68.
Hiroyuki Ohno Shinji Takeoka Hidetaka Iwai Eishun Tsuchida 《Journal of polymer science. Part A, Polymer chemistry》1987,25(10):2737-2746
1-Palmitoyl-2(2,4-octadecadienoyl)-sn-glycero-3-phosphocholine (POPC), a polymerizable lipid that contains one diene group in only a 2-acyl chain, was polymerized as liposome in an aqueous medium. Polymerization was initiated by water-insoluble azobisisobutyronitrile (AIBN), or water-soluble azobis(2-amidinopropane) dihydrochloride (AAPD). AIBN was mixed with monomeric lipids, and the mixture was dispersed in an aqueous medium by sonication to prepare AIBN-containing monomeric lipid liposomes. On the other hand, AAPD was simply added to the liposome suspension. The POPC liposomes were easily polymerized by the addition of AAPD, a water-soluble radical initiator, but few were polymerized by AIBN. The results suggested that the diene group in the 2-acyl chain was in an aqueous phase and, therefore, easily polymerized by a water-soluble radical initiator. The polymerized POPC liposomes were revealed to be more stable than those of monomeric ones because the scattered-light intensity from the polymerized POPC liposome suspension changed a little by the addition of Triton X-100. For only the polymerized ones, the liposome structure was confirmed by TEM after addition of an excess amount of Triton X-100. 相似文献
69.
Cloud points of aqueous solutions of homogeneous poly(oxyethylene)dodecyl ether derivatives (C12(OE)n: n=2–8) and the apparent theta temperatureT
ap
were determined from the abrupt changes in optical transmittance and the temperature dependence of the second virial coefficient obtained by light scattering measurements. It was found that the lower critical solution temperature (LCST) shifts to a lower temperature and lower concentration as the number of oxyethylene units in a molecule decreases. Because of this behavior of LCST, the modified Flory-Schultz plot of phase separation was applied to the present nonionic surfactant-water system, and its theta temperature obtained. The dependence ofT
ap
on the number of oxyethylene units suggests that the polyoxyethylene chain has different effects on the solubility of C12(OE)n in water forn less than or equal to 3 from those forn greater than or equal to 4. 相似文献
70.
H. Fujimatsu S. Ogasawara N. Satoh K. Komori Y. Matsunaga S. Kuroiwa 《Colloid and polymer science》1990,268(2):143-147
Adhesive effect of low density polyethylene (LDPE) gels in organic solvents such as decalin, tetralin, ando-dichlorobenzene on high density polyethylene (HDPE) moldings has been investigated by shearing tests, electron microscopy, and DSC measurements. When heated at 110°C for 2 h, all of the gels showed strong adhesive strengths around 30 kg/cm2, which is sufficiently strong for practical uses. It has been found that the adhesive strength increases with the heating temperature and that the temperature at which the heated gel begins to exhibit the adhesive effect depends upon solvents and is about 30° lower than that of the HDPE gels. 相似文献