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101.
This paper describes recent progress in flow visualization techniques from the viewpoint of visual art incorporating fluid
motion. The images of fluid art introduced here are categorized into four groups: the reflected or refracted patterns of free
surface motion in nature and in a controlled environment, the coherent turbulent phenomena of fluid flow, and the fluid motion
induced by the physical properties of fluids. It is shown that flow visualization techniques, which were originally developed
in the field of engineering, have been successfully applied to the creation of artistic images. 相似文献
102.
Kazuo Sasazawa Yuko Yamada Akiko Fujisawa Toshikazu Saitoh Katsuya Ueno Kazuya Oharu Hideo Sawada 《Colloid and polymer science》2005,283(7):812-816
Self-assembled fluorinated molecular aggregates formed by fluoroalkyl end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomers, N,N-dimethylacrylamide oligomers, and acrylic acid oligomers in methanol could selectively recognize fluoresceins as guest molecules to form a new class of fluorinated aggregates-fluorescein nanocomposites. These fluorinated fluorescein nanocomposites that are obtained exhibit an extraordinarily enhanced light absorption (max ca. 440 nm) compared to that (maxs 452, 480 nm) of the parent fluorescein in the absence of fluorinated aggregates. 相似文献
103.
Claw Conditions for Heavy Cycles in Weighted Graphs 总被引:1,自引:0,他引:1
Jun Fujisawa 《Graphs and Combinatorics》2005,21(2):217-229
A graph is called a weighted graph when each edge e is assigned a nonnegative number w(e), called the weight of e. For a vertex v of a weighted graph, dw(v) is the sum of the weights of the edges incident with v. For a subgraph H of a weighted graph G, the weight of H is the sum of the weights of the edges belonging to H. In this paper, we give a new sufficient condition for a weighted graph to have a heavy cycle. A 2-connected weighted graph G contains either a Hamilton cycle or a cycle of weight at least c, if G satisfies the following conditions: In every induced claw or induced modified claw F of G, (1) max{dw(x),dw(y)} c/2 for each non-adjacent pair of vertices x and y in F, and (2) all edges of F have the same weight. 相似文献
104.
Spin relaxation from a triplet excited state to a singlet ground state in a semiconductor quantum dot is studied by employing an electrical pump-and-probe method. Spin relaxation occurs via co-tunneling when the tunneling rate is relatively large, confirmed by a characteristic square dependence of the relaxation rate on the tunneling rate. When co-tunneling is suppressed by reducing the tunneling rate, the intrinsic spin relaxation is dominated by spin-orbit interaction. We discuss a selection rule of the spin-orbit interaction based on the observed double-exponential decay of the triplet state. 相似文献
105.
The KrF2 - zeolite 13X reaction at ?40 °C results in entrapment of Kr in the zeolite. On heating, a portion of the entrapped Kr is retained up to 500 °C. The Kr loading is more than 8 cc(STP)/g at a storage temperature of 100 °C. The present work has suggested a feasibiltty of the zeolite encapsulation of radioactive krypton by a chemical procedure. 相似文献
106.
Photoelectron spectroscopy was applied for the first time to the study of a photochemical reaction in solids, the reaction of a rubrene film being taken as an example. The measurement of the absorption spectrum indicates that the photo-oxidation takes place in the bulk. The change of the photoelectron spectrum shows that about 50% of the original rubrene is recovered upon heating the peroxide. 相似文献
107.
Hasegawa T Fujisawa T Numata M Umeda M Matsumoto T Kimura T Okumura S Sakurai K Shinkai S 《Chemical communications (Cambridge, England)》2004,(19):2150-2151
Single-walled carbon nanotubes can be entrapped within a helical superstructure composed of schizophyllan bearing lactoside-appendages to show an excellent water-solubility as well as a specific lectin-affinity. 相似文献
108.
Surprisingly stable synperiplanar conformers of CFTA esters have led us to develop a new and very reliable method for assigning absolute configurations of even secondary alcohols having minimal structural differences, such as chiral benzhydrols and alpha-monodeuterated benzyl alcohols. 相似文献
109.
Baba D Ishii H Higashiya S Fujisawa K Fuchigami T 《The Journal of organic chemistry》2001,66(21):7020-7024
Anodic fluorination of N-benzoyl, N-acethyl-, and N-formylthiazolidine derived from L-cysteine was carried out in dimethoxyethane (DME) and acetonitrile containing various supporting fluoride salts using an undivided cell. Highly regioselective fluorination proceeded to provide the corresponding 5-monofluorinated thiazolidine derivatives in good yields in DME, and the diastereoselectivitiy was moderate to high regardless of the supporting fluoride salts. The diastereoselectivitiy of the fluorination was greatly affected by the bulkyness of the subsitituent on the nitrogen atom, and N-benzoylthiazolidine gave much higher diastereoselectivity compared with N-formyl derivative. The fluorination of the thiazolidines was not achieved by commercially available fluorinating reagents such as N-fluoropyridinium salts. 相似文献
110.
J. Fujisawa Y. Iwasaki Y. Ohba S. Yamauchi N. Koga S. Karasawa M. Fuhs K. Möbius S. Weber 《Applied magnetic resonance》2001,21(3-4):483-493
The photoexcited quartet (Q1) and doublet (D1) states of the complex of tetra-phenyl-porphine zinc (II) and a nitroxide radical have been studied in toluene solution by X-(9.4 GHz) and W-band (94 GHz) time-resolved electron paramagnetic resonance spectroscopy. The spin-polarized signals of the Q1 and D1 states are observed and assigned by analysis of theg-values. Line broadening and spin polarization mechanisms in this system are discussed. 相似文献