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201.
Dr.-Ing. Hideo Ohashi 《Archive of Applied Mechanics (Ingenieur Archiv)》1959,27(4):201-226
Ohne ZusammenfassungGekürzte Fassung der von der Fakultät für Maschinenwesen der Technischen Hochschule Braunschweig genehmigten gleichnamigen Dissertation. Berichter: Prof. Dr. H. Schlichting; Mitberichter: Prof. Dr. H. Petermann. Die Untersuchungen wurden im Institut für Strömungsmechanik der Technischen Hochschule Braunschweig unter der Leitung von Prof. Dr. H. Schlichting durchgeführt und durch die Deutsche Forschungs-gemeinschaft und ein Stipendium des Verfassers vom Deutschen Akademischen Austauschdienst ermöglicht.Bei der Abfassung dieser gekürzten. Fassung hat Herr Dr.-Ing. K. Gersten mitgewirkt. 相似文献
202.
Kenzo Ohkita Hideo Kurosawa Toshikazu Hirao Isao Ikeda 《Journal of organometallic chemistry》1994,470(1-2):189-190
Relative stability in coordination of substituted styrene derivatives to [Ru(η-C5H5)(dtpe)]+ (dtpe = 1,2-bis(di-p-tolylphosphino)-ethane) was determined by NMR spectroscopy to reveal unusually weak substituent dependency of the stability. 相似文献
203.
Kazuki Aita Takashi Temma Yoichi Shimizu Yuji Kuge Koh-ichi Seki Hideo Saji 《Journal of fluorescence》2010,20(1):225-234
Fluorescent analysis has been widely used in biological, chemical and analytical research. A useful fluorescent labeling agent
should include NIR emission, a large Stoke’s shift, and good labeling ability without interfering with the pharmacological
profile of the labeled compound. Thus, we planned to develop an M-AMF-DOTA(Nd) derivative composed of an NIR fluorescent moiety
and a maleimide conjugating moiety as a new NIR fluorescent labeling agent which fulfills these requirements. M-AMF-DOTA(Nd)
was synthesized from 4-amino-fluorescein and was conjugated with an avidin molecule (Avidin-AMF-DOTA(Nd)) through Lys-side
chains by reaction with 2-iminothiolane. The fluorescent features of M-AMF-DOTA(Nd) and Avidin-AMF-DOTA(Nd) were comparatively
evaluated. A binding assay of Avidin-AMF-DOTA(Nd) with D-biotin and a tumor cell-uptake study were performed to estimate the
effects of conjugation on the biological and physicochemical features of the protein. M-AMF-DOTA(Nd) was obtained in 22% overall
yield. M-AMF-DOTA(Nd) had a typical NIR fluorescence from the Nd ion (880 nm and 900 nm from 488 nm excitation). Avidin-AMF-DOTA(Nd)
was easily synthesized and also had typical NIR fluorescence from the Nd ion without loss of fluorescent intensity. The binding
affinity of Avidin-AMF-DOTA(Nd) to D-biotin was equivalent to naive avidin. Avidin-AMF-DOTA(Nd) was taken up by tumor cells
in the same manner as avidin conjugated with fluorescein isothiocyanate, an established, widely used fluorescent avidin. Results
from this study indicate that M-AMF-DOTA(Nd) is a potential labeling agent for routine NIR fluorescent analysis. 相似文献
204.
Fine metal particles (nanoparticles) stabilized on porous (polymeric) substrates can be considered as a model system of a high-performance catalyst. In the present study, the substrate was made using the periodic microphase-separated structure of a block copolymer as the template, and the Pd nanoparticles were formed inside the porous material by reduction of the Pd2+ ions with 1-propanol as the reductant. The three-dimensional morphology of such a polymer-Pd hybrid material was studied by transmission electron microtomography. The characteristic structural parameters of the hybrid, e.g., the penetration of the Pd nanoparticles into the polymer substrate, number density of the Pd nanoparticles, and size distribution of the Pd nanoparticles, were measured for the first time. 相似文献
205.
Uzawa H Nagatsuka T Hiramatsu H Nishida Y 《Chemical communications (Cambridge, England)》2006,(13):1381-1383
Glucuronidase-catalyzed transglycosylation was examined by using 4-nitrophenyl beta-D-glucuronide (D-GlcA-O-pNP) as the glycosyl donor; when pNP 6-O-sulfo-beta-D-gluco- and D-galacto-pyranosides were used as the acceptors, a bovine enzyme was found to construct beta-D-GlcA-(1-3)-linkages with the 6-O-sulfo-sugars in both a site- and beta-selective way. 相似文献
206.
Here we show, analytically and numerically, that in a TiO(2) double-groove grating with two different groove widths per period attached on the SiO(2) substrate, the normally incident light couples to the +1st-order transmission with 96.9% efficiency and with a 50° diffraction angle that is larger than the SiO(2)-air interface critical angle. Modal analysis reveals that three propagating modes for the +1st diffraction order reach the grating back end in phase, while the corresponding propagating modes for the -1st and zeroth orders are added destructively at the grating end. Four optical devices based on this grating characteristic are numerically demonstrated. 相似文献
207.
Izumi T Naitou Y Shimbo Y Takanishi Y Takezoe H Watanabe J 《The journal of physical chemistry. B》2006,110(47):23911-23919
The mesomorphic behavior and phase structure were examined in the mixture of two kinds of dimeric compounds, alpha,omega-bis(4-alkoxyanilinebenzylidene-4'-carbonyloxy)pentane (mOAM5AMOm), by optical microscopy, X-ray diffraction, polarization switching, and second-harmonic generation measurements. One compound is 4OAM5AMO4 with a short terminal alkyl chain that forms a single-layer smectic phase (SmCAs) with a random mixing of spacer and tail groups. Another compound is 16OAM5AMO16 with a long terminal alkyl chain that forms a chiral, anticlinic, and antiferroelectric bilayer phase (SmCAb) with the bent molecules tilted to the bilayer. By mixing these two compounds, the SmCAs phase of 4OAM5AMO4 is easily destabilized, leading to the wide content region of the bilayer phases. In the bilayer regime, three other smectic phases are newly induced. Two of them are antiferroelectric and ferroelectric phases in which the molecules lie perpendicularly with respect to the layer. The other shows no polar response to an external electric field and behaves like a smectic A. The new appearance of these bilayer phases is discussed as a mixing effect of long and short tail groups. 相似文献
208.
Shimada T Kondoh H Iwasaki M Nakai I Nagasaka M Amemiya K Orita H Ohta T 《The journal of physical chemistry. B》2006,110(41):20507-20512
The adsorption structure of NO on the reconstructed Pt(110)-(1 x 2) surface was studied with X-ray photoelectron spectroscopy (XPS), X-ray photoelectron diffraction (XPD), low-energy scanned-angle photoelectron diffraction (LESA-PD), and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. The experiments were performed at 180 K, where no surface lifting from (1 x 2) to (1 x 1) takes place after NO adsorption. XPS indicates that the (1 x 2) unit cell of the Pt(110) surface contains 1.5 NO molecules at the saturated coverage. XPD and LESA-PD analyses allow us to propose a structural model for the NO adlayer, where two-thirds of the NO molecules in the (1 x 2) unit cell are adsorbed on the atop site of the close-packed Pt rows (ridges) along the [10] direction with an inclined geometry and one-third of the NO molecules adsorb on the bridge site between the Pt ridges with an upright configuration. This model is supported by the N K-edge NEXAFS experiments and is consistent with the recently reported model based on the density functional theory (Orita, H.; Nakamura, I.; Fujitani, T. J. Phys. Chem. B 2005, 109, 10312). 相似文献
209.
Matsuya Y Kawaguchi T Ishihara K Ahmed K Zhao QL Kondo T Nemoto H 《Organic letters》2006,8(20):4609-4612
Hybrid compounds of macrosphelides and epothilones, both of which are natural macrolides having a 16-membered skeleton, were designed and synthesized using a ring-closing metathesis (RCM) strategy. Some of these hybrids were found to exhibit notable apoptosis-inducing activity against human lymphoma cells with higher potency than parent natural macrosphelides, and to be a promising lead compound for development of a new antitumor agent. 相似文献
210.
A quadrangulation is a simple graph on the sphere each of whose faces is quadrilateral. A quadrangulation G is said to be tight if each edge of G is incident to a vertex of degree exactly 3. We prove that any two tight quadrangulations with n?11 vertices, not isomorphic to pseudo double wheels, can be transformed into each other, through only tight quadrangulations, by at most rhombus rotations. If we restrict quadrangulations to be 3-connected, then the number of rhombus rotations can be decreased to 2n-22. 相似文献