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61.
62.
The transition temperatures between high- and low-spin states of the assembled spin-crossover complexes, Fe(NCX)2(bpa)2(guest) (X = S, Se, BH3; bpa = 1,2-bis(4-pyridyl)ethane; guest = biphenyl, 2-nitrobiphenyl, diphenylmethane, or 1,4-dichlorobenzene), were compared with the Mössbauer parameters. The transition temperature increases when the QS value of FeII high-spin state becomes small. The transition temperature also increases by changing the anion from NCS to NCSe and then to NCBH3. 相似文献
63.
64.
Road signs must provide a conspicuous signal to a wide variety of drivers over a broad range of environmental and geometric
conditions. Recently, there are an increasing number of applications in which light emitting diodes (LEDs) are used as the
light source, including critical transportation signaling. In the presence of fog, the resulting visual signal is disturbed
due to light scattering by airborne water droplets. By measuring LED brightness with human spectral sensitivity in various
densities and various droplet sizes (10, 30, 50, and 100 μm), it is understood that the particle size distribution (fog droplet
size) and density of fog does affect visibility in fog. The colored LEDs that contain a yellow component had high brightness
evaluation, blue component had low brightness evaluation in all densities and different droplet sizes. The result in this
paper can contribute to air and land traffic safety and the prevention of accidents. 相似文献
65.
Kon N Takemura H Otsuka K Tanoue K Nakashima S Yasutake M Tani K Kimoto J Shinmyozu T Inazu T 《The Journal of organic chemistry》2000,65(12):3708-3715
Macropolycyclic cage compounds were synthesized by a direct reaction between diamines and bis(bromomethyl) compounds. The procedure for constructing the polycyclic cage structure is simple and straightforward. The macropolycyclic compounds obtainable from this cyclization procedure are three-dimensional cage compounds, and any other isomers were not obtained except for two examples. Benzene, pyridine, and aliphatic units could be introduced into the cage structure. The macrocycles that have strong cation affinity were obtained as their potassium complexes. 相似文献
66.
Hiroyasu Sato Yoshihumi Kusumoto Nobuaki Nakashima Keitaro Yoshihara 《Chemical physics letters》1980,71(2):326-329
The mechanism of enhancement in the energy transfer between rhodamine 6G and 3,3'-diethylthiacarbocyanine iodide by sodium lauryl sulfate in the premicellar region was studied by a picosecond laser technique. The Forster mechanism with an increased local concentration suggesting dye-rich induced micelle formation was concluded from the shape of the decay curve. 相似文献
67.
The natural abundance 13C magnetic resonance spectra of some Papaveraceae alkaloids have been determined at 22·628 MHz employing the pulse Fourier transform technique. Several techniques were employed to aid in spectral assignments and it has been possible to make self-consistent assignments for all the resonances for these alkaloids. Evidence is presented for trans-annular interaction between the amino group and the carbonyl group situated across the ten-membered ring. 相似文献
68.
Shigeyuki Mayama Toshikazu Tani Tamio Ueno Kazumasa Hirabayashi Tadakazu Nakashima Hiroshi Fukami Yukio Mizuno Hiroshi Irie 《Tetrahedron letters》1981,22(22):2103-2106
The major phytoalexin from oat leaves has been identified as 2-[2-(4-hydroxyphenyDethenyl] -6-hydroxy-4H-3,1-benzoxazin-4-one (). 相似文献
69.
Photoluminescence excitation spectra of donor-acceptor pairs have been observed in phosphorus doped ZnTe. Binding energies of the donor and the acceptor is estimated from the spectra. Emission spectra measured under below-band-gap excitation showed sharp bands superimposed with a broad emission band. The result indicates the existence of two decay processes under the below-band-gap excitation: (1) recombination of an electron and a hole trapped on a given D-A pair, and (2) recombination of D-A pairs with various distances for which bound electrons are formed via conduction band. 相似文献
70.
Cho T Yoshida M Kohagura J Hirata M Numakura T Higaki H Hojo H Ichimura M Ishii K Islam KM Itakura A Katanuma I Nakashima Y Saito T Tatematsu Y Yoshikawa M Kojima Y Tokioka S Yokoyama N Tomii Y Imai T Pastukhov VP Miyoshi S;GAMMA Group 《Physical review letters》2005,94(8):085002
Vortexlike turbulent structures in hot-ion mode plasmas with several keV are observed in the case with a radially produced weak shear of electric fields E(r). However, a strong E(r) shear formation due to a high ion-confining potential phi(c) production clears up these vortices together with plasma-confinement improvement and disappearance of both drift-wave and turbulencelike Fourier spectral signals. These findings are based on three-time progress in phi(c) in comparison to phi(c) attained 1992-2002. The significant advance of phi(c) is well extended in line with proposed potential-formation physics scalings. 相似文献