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121.
PHOTOCHROMISM AND LUMINESCENCE OF DOPANT CHROMOPHORES THROUGH TWO-PHOTON IONIZATION IN POLYMER FILMS
Two-photon ionization and recombination processes of an aromatic chromophore doped in polymer films werestudied and the features of these processes were discussed in relation to photofunctional polymers, An aromatic moleculehaving low ionization potential, e.g., N,N,N',N'-tetramethyl-p-phenylene diamine doped in poly(methyl methacrylate)(PMMA) film was easily photoionized by intense laser ligh excitation, giving a colored radical cation (photochromism) anda trapped electron in PMMA matrix. As a reversed process, the radical cation recombined with the trapped electron, showingdiscoloration and emitting luminescence, either isothermal luminescence (ITL), or thermoluminescence (TL). In this report,ITL and TL through the charge recombination process were studied and the luminescence was suggested as a mean of the read-out of photorecording. 相似文献
122.
Kenji Sasaki Yasuyoshi Satoh Takashi Hirota Taiji Nakayama Yoshinori Tominaga Raymond N. Castle 《Journal of heterocyclic chemistry》2000,37(4):959-967
Naphtho[1,2‐b][1]benzothiophene‐6‐carboxylic acids, 6H‐benzo[b]naphtho[2,3‐d]thiopyran‐6‐ones and 6H‐benzo[b]naphtho[2,3‐d]pyran‐6‐ones were synthesized in one step by the photocyclization reaction of 3‐aryl‐2‐([1]benzothien‐3‐yl)propenoic acids. The photocyclization reaction did not occur when the 3‐aryl group contained the electron‐withdrawing nitro group. The assignment of the 1H and 13C nmr spectra of 6H‐benzo[b]naphtho[2,3‐d]thiopyran‐6‐one and 6H‐benzo[b]naphtho[2,3‐d]pyran‐6‐one by two‐dimensional nmr methods is described. The difference between the chemical shift values of H12 for these two compounds is attributed to different molecular geometries. 相似文献
123.
Y. Iwadate J. Tominaga K. Igarashi K. Kawamura J. Mochinaga 《Journal of solution chemistry》1985,14(1):59-66
Refractive indices of a certain molten nitrate mixture measured goniometrically with visible light at nine wavelengths, varied linearly with temperature at a given wavelength. Dispersion phenomenon was also observed at a fixed temperature. Electronic polarizability was determined using the refractive index extrapolated to infinite wavelength and the semiclassical Clausius-Mossotti equation. 相似文献
124.
125.
The concept of a binary feature tree (BFT) and the principle of its formation are described. A pattern is divided into sub-parts by comparing its similarity with other patterns. The BFT is established by sub-parts of a group of patterns and mapped into a three layered neural network which Sethi called an entropy network. The interconnection pattern between the first and hidden layers is formed according to the “AND“ relationship of node feature patterns determined by BFT. The interconnection pattern between the hidden and last layers is obtained by training. The advantage of the proposed network is that the scale is small because a feature neuron is adopted and the interconnection is local instead of full; therefore, it is easily implemented by either hardware or software. Two simulation examples show the success of the entropy network for pattern recognition. A feature extraction by an optical inner product method is also described.Presented at 1996 International Topical Meeting on Optical Computing (OC ‘96), April 21-25, Sendai, Japan. 相似文献
126.
127.
Masahide Monde Tsuyoshi Uematsu Toshiki Toda Kazuhiko Ohnuma Yoshizumi Yasuda 《Optical Review》1995,2(2):132-134
To make holograms from computer graphic (CG) in a short time, a new holographic three dimensional (3D) printer is proposed here. This printer consists of galvanometer scanners, a micro computer and a laser, and uses a holographic contact duplicating method. Experiments have shown that a hologram of 39 × 41 mm can be obtained in 4 min.Presented at the International Commission for Optics Topical Meeting, Kyoto, 1994. 相似文献
128.
M. Tanaka Y. Sakai T. Tominaga A. Fukuoka T. Kimura M. Ichikawa 《Journal of Radioanalytical and Nuclear Chemistry》1989,137(4):287-297
Phthalocyanineiron/II/ in NaY zeolite was synthesized via various processes from an iron carbonyl compound into NaY zeolite in gaseous phase. Mössbauer spectra of the final product /phthalocyanineiron/II// and the precursor species /iron oxide and [phthalocyaninato/2-/]bis/pyridine/iron/II// in NaY zeolite were measured to characterize the chemical and physical states of the iron species. 相似文献
129.
Yoshinori Tominaga 《Journal of heterocyclic chemistry》1989,26(5):1167-1204
This review described developments in the synthesis of heterocyclic compounds using carbon disulfide and their products. 相似文献
130.
We describe spatial arrangement of polystyrene latex using a microscopic imaging system. A reduced photomask pattern is imaged on the particles in a water-filled cell so that polystyrene spheres align in a two-dimensional pattern. Calculating the forces exerted on the spheres by isolated line pattern, we investigated an optimum size for sphere diameter and the line width of the patterns. We are able to align spheres in real-time by this technique. 相似文献