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31.
S. Nakajima H. Hayashi K. OHSHIMA K. Yamazaki Y. Kubo N. Samejima Y. Kakiuchi Y. Shindoh H. Koshimizu I. Sakata H. Yamauchi 《Photochemistry and photobiology》1987,46(5):783-788
Abstract Mono-DPTA-ethyleneglycol-Ga-deuteroporphyrin (MDEGD) was synthesized, by coordinating non-radioactive Ga in the porphyrin ring and connecting DTPA (diethylene-triamine-N,N,N,N,N,-pentaacetic acid) to its side chain. By labeling with 111In , chemicals for scintigraphy were developed. They were applied to Syrian golden hamsters with implanted pancreatic gland cancers and C57-black mice with Lewis lung cancer to enable tumor imaging and biodistribution examination. A comparative study was also conducted with [67 Ga]citrate. In the resultant data, [111 In]MDEGD showed larger tumor/lung, tumor/kidney and tumor/blood ratio with [67 Ga]citrate. The affinity of [n In]MDEGD in inflammatory tissue was much lower than that of 67 Ga citrate. [111 In]MDEGD lost its photosensitivity. 相似文献
32.
Three acyclic polythioethers containing 2-thienyl units at both ends were synthesized and the effect of substituent on the extraction of copper(II) was studied. The methyl groups in the terminal thiophene ring have imparted an appreciable degree of increase in the percent extraction of copper(II), while the introduction of chlorine atoms into the 2-thienyl unit resulted in the reverse effect. Among the counter dye anions examined, tetrabromophenolphthalein ethylester was the best one for copper(II) extraction. The composition of extracted species was evaluated to be 122 (Cu(II)/polythioether/dye anion). Quantitative extraction of copper(I) was attained as complexes with various triphenylmethane dyes, i.e., bromocresol green, bromothymol blue, bromo-phenol blue and pyrogallol red. Copper(I) in organic phase was completely back-extracted with 2 mole/l sulfuric acid containing 10% hydrogen peroxide. 相似文献
33.
Pimpisut Worakajit Pinit Kidkhunthod Thanasee Thanasarnsurapong Saran Waiprasoet Hideki Nakajima Taweesak Sudyoadsuk Vinich Promarak Adisak Boonchun Pichaya Pattanasattayavong 《Advanced functional materials》2023,33(25):2209504
Solution-processed copper(I) thiocyanate (CuSCN) typically exhibits low crystallinity with short-range order; the defects result in a high density of trap states that limit the device's performance. Despite the extensive electronic applications of CuSCN, its defect properties are not understood in detail. Through X-ray absorption spectroscopy, pristine CuSCN prepared from the standard diethyl sulfide-based recipe is found to contain under-coordinated Cu atoms, pointing to the presence of SCN− vacancies. A defect passivation strategy is introduced by adding solid I2 to the processing solution. At small concentrations, the iodine is found to exist as I− which can substitute for the missing SCN− ligand, effectively healing the defective sites and restoring the coordination around Cu. Computational study results also verify this point. Applying I2-doped CuSCN as a p-channel in thin-film transistors shows that the hole mobility increases by more than five times at the optimal doping concentration of 0.5 mol.%. Importantly, the on/off current ratio and the subthreshold characteristics also improve as the I2 doping method leads to the defect-healing effect while avoiding the creation of detrimental impurity states. An analysis of the capacitance-voltage characteristics corroborates that the trap state density is reduced upon I2 addition. 相似文献
34.
Yoshitake Hashimoto 《Communications in Mathematical Physics》1993,151(3):481-485
We give the correspondence between instantons onS
4 and some representations of an associative algebra. For the given structure group, we get simultaneous imbeddings to (the inductive limit) of the moduli spaces for instantons onS
4 of all instanton numbers. 相似文献
35.
36.
Water-swellable polyelectrolyte microgels polymerized in an inverse microemulsion using a nonionic surfactant 总被引:5,自引:0,他引:5
A series of poly(dimethylacrylamide-co-2-acrylamido-2-methyl-1-propanesulfonic acid) microgels slightly crosslinked by methylene-bis-acrylamide (MBA) were polymerized in a novel inverse microemulsion polymerization (IMEP) system. To determine a suitable composition of the IMEP system, the phase diagram of a pseudoternary system was made. The pseudoternary polymerization system consisted of n-hexane, a nonionic surfactant (polyoxyethylene oleyl ether, C18En), and an aqueous monomer solution. Polymerization was performed in a single-phase reversed micelle solution. The reversed micelles were about 50 nm in diameter, as determined by FF-TEM. The viscometric characteristics of the polymers extracted from the IMEP system were studied in 3 mM sodium chloride aqueous solution. The intrinsic viscosity values for the noncrosslinked and crosslinked (0.1 mol% MBA was incorporated) samples were 25 and 7.4 dl/g, respectively. The overlap concentration (c*) of crosslinked polymer microgel occurred at c[eta] = 1 in the solvent. When the volume fraction (phi) of the microgel was 0.7, the value of the apparent yield stress of the microgel solution was observed. These results show that the microgel has a significant thickening effect above c* due to friction between the microgel particles. It is assumed that the microgels polymerized in a confined space retain the shape or size of the nanosized reactor with a diameter on the order of 50 nm. 相似文献
37.
Phenols are deprotected with weak bases from their tert-butoxycarbonyl (Boc) derivatives. Boc deprotection with bases can avoid side reactions during the deprotection with acids. We note the lability of the Boc to bases and are able to utilize it as a new cleavage condition for synthetic studies. 相似文献
38.
39.
Ohne Zusammenfassung 相似文献
40.
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