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11.
12.
Pyrene-azacrown ether hybrid: cation-π interaction   总被引:1,自引:0,他引:1  
A pyrene-modified lariat ether was synthesized in order to observe the cation-π interaction in solution.  相似文献   
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Emission from high-energy-electron-irradiated golden hamster embryo (GHE) cells has been studied over the temperature range 12–300 K both by a one-shot-single-photon-counting method and by photocurrent measurements with an oscilloscope. Emission from the irradiated phosphate buffered saline (PBS) also has been studied. The emission spectra from PBS at 12 and 77 K show a maximum around 330 and 380 nm, respectively, which are the same spectra as those from irradiated pure H2O. The emission from irradiated GHE consists of the new band at 480 nm in addition to the emission from H2O. The 480 nm emission is observed at the temperature range of 12–300 K, though the emission at 300 K is much lower than that at low temperature. The 480 nm emission is ascribed to the transition from excited organic substances in GHE cells. The intensity of 480 nm emission at 300 K increases linearly with increasing irradiation-dose in the range of 11–600 Gy.  相似文献   
15.
The orthonormality-constrained variation method is developed, the application of which gives an exact SCF equation. The variational procedure used in deriving the equation clarifies the source and meaning of two kinds of arbitrary parameters which appear by the use of the method of lagrangean multipliers.  相似文献   
16.
The dielectric solvent effect on HCCH, HCNH and HCNC spin coupling constants in ethane, tetrachloroethane and trans N-methylformamide has been calculated by finite perturbation theory based on the INDO and CNDO/2 approximations incorporating solvaton theory. The available experimental data are interpreted using the calculated variations of spin coupling constants. The effect of dielectric constant on the general form of the Karplus relation is included in the finite perturbation calculations.  相似文献   
17.
Samples (0.5 g) are decomposed with mixed acids in a sealed teflon vessel. After suitable treatment, barium, cobalt, chromium, copper, lithium, nickel, scandium. strontium, vanadium and zirconium are determined sequentially. The method is satisfactory for a variety of standard silicate materials.  相似文献   
18.
Summary. Development of new odorless thiols (dodecanethiol, 4-n-heptylphenylmethanethiol, 4-trimethylsilylphenylmethanethiol, 4-trimethylsilylbenzenethiol) and an odorless sulfide (1-methylsulfanyldodecane) and their applications to dealkylation, Michael addition, Swern oxidation, and Corey-Kim oxidation are described.  相似文献   
19.
A negative-ion-based neutral beam injector (N-NBI) has been constructed for JT-60U. The N-NBI is designed to inject 500 keV, 10 MW neutral beams using two ion sources, each producing a 500 keV, 22 A D ion beam. In the preliminary experiment using one ion source, a D ion beam of 13.5 A has been successfully accelerated with an energy of 400 keV (5.4 MW) for 0.12 s at an operating pressure of 0.22 Pa. This is the highest D beam current and power in the world. Co-extracted electron current was effectively suppressed to the ratio of Ie/ID < 1. The highest energy beam of 460 keV, 2.4 A, 0.44 s has also been obtained. To realize 1 MeV class NBI system for ITER (International Thermonuclear Experimental Reactor), demonstration of ampere class negative ion beam acceleration up to 1 MeV is an important mile stone. To achieve the mile stone, a prototype accelerator and a 1 MV, 1 A test facility called MeV Test Facility (MTF) were constructed. Up to now, an H ion beam was accelerated up to the energy of 805 keV with an acceleration drain current of 150 mA for 1 s in a five stage electrostatic multi-aperture accelerator.  相似文献   
20.
TUMOR-LOCALIZING FLUORESCENT DIAGNOSTIC AGENTS WITHOUT PHOTOTOXICITY   总被引:2,自引:0,他引:2  
In order to develop tumor-localizing fluorescent diagnostic agents without phototoxicity, various heterodimers linked by some spacers between a chlorine derivative and its Mn or Cu complex were synthesized. The representative agent of them was named HAT-D01 and has a molecular formula of m -phthalyl-{[13,17-bispropanoic acid-3-ethenyl-8-formylethylidene-7-hydroxy-2,7,12,18-tetramethyl-porphyrinate]-manganese (III)}-[3'-ethenyl-8'-formylethylidene-7'-hydroxy-2',7', 12', 18'-tetramethyl-porphine-13', 17'-bispropanoyl aspartic acid]-bishydrazone.  相似文献   
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