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991.
Upconversion luminescence has been studied for Er3+ in a germanate-oxyfluoride and a tellurium-germanate-oxyfluoride transparent glass-ceramic using 800 nm excitation. Significantly increased upconversion luminescence was observed from transparent glass-ceramics compared with that from their corresponding as-prepared glasses. In addition to a strong green emission centered at 545 nm from 4S3/2 state and a weaker red emission centered at 662 nm from 4F9/2 state generally seen from Er3+-doped glasses, a violet emission centered at 410 nm from 2H9/2 state and a near-ultra-violet emission centered at 379 nm from 4G11/2 state were also observed from transparent glass-ceramics. The upconversion luminescence of Er3+ ions in transparent glass-ceramics revealed sharp Stark-splitting peaks generally seen in a crystal host. The increased upconversion efficiency is attributed to the decreased effective phonon energy and the increased energy transfer between excited ions when Er3+ ions were incorporated into the precipitated β-PbF2 nanocrystals. 相似文献
992.
993.
994.
Manabu Node Takeo Kawabata Masaru Ueda Mayumi Fujimoto Kaoru Fuji Eiichi Fujita 《Tetrahedron letters》1982,23(39):4047-4050
The nitrogroup in primary α-nitroketones is converted into hydrogen with aluminum chloride and ethanethiol. 相似文献
995.
K. Maeda O. Ueda Y. Murayama K. Sakamoto 《Journal of Physics and Chemistry of Solids》1977,38(10):1173-1179
Mechanical properdes of GaP single crystals have been investigated from 100° to 300°C by observing dislocation rosette patterns on indented specimen surfaces. It has been found that GaP has mechanical properties which are common to those of other III–V compounds or elemental semiconductors in several points: the {111} surface polarity dependence of microhardness, the mobility difference between α- and β-dislocations, and the conduction type dependence of dislocation mobility. The growth of dislocation rosettes is suppressed by baking specimens in air. Contrary to the case of II–VI compounds, illumination of visible light during indentation enhances the mobility of dislocations. These experimental results are discussed in terms of an effect of electronic charge of dislocation on its mobility. 相似文献
996.
997.
998.
Katsuma Hiraki Masayoshi Onishi Kohji Ohnuma Keiichi Sugino 《Journal of organometallic chemistry》1981,216(3):413-419
Reaction of iodotrimethylplatinum(IV) tetramer with bis(1,3-diphenyl-2-imidazolidinylidene) [(Hdpim)2] gave a new dinuclear carbene complex, [{Pt(dpim)I}2](dpim 1,3-diphenyl-2-imidazolidinylidenato-2-C,2′-C), III, in 84% yield, which contains a cycloplatinated carbene structure. Some mononuclear derivatives, [Pt(dpim)(acac)], [Pt(dpim)I{P(OCHMe2)3}], [Pt(dpim)-(NCCH3)2]ClO4, and [Pt(dpim)(COD)]ClO4 were prepared from III and characterized by means of elemental analysis, IR and NMR spectroscopy, and molar conductivity. An intermediate species, [{PtMeI(Hdpim)}2], leading to III is discussed also. 相似文献
999.
Yoshio Imai Mitsuru Ueda Tatsuo Aizawa 《Journal of polymer science. Part A, Polymer chemistry》1978,16(1):163-168
A new class of polydihydropyridazinones has been synthesized by the solution cyclopolycondensation in m-cresol of 4,4′-oxy- and 4,4′-ethylenebis(3-benzoylpropionic acids) with aromatic dihydrazines such as bis(4-hydrazinophenyl) sulfone and bis(4-hydrazinophenyl)methane. The polymers having inherent viscosities of 0.2–0.4 were highly soluble in a wide range of solvents including m-cresol, N,N-dimethylacetamide, and pyridine. Thermogravimetric analysis of the polydihydropyridazinones showed initial weight losses commencing at 290–350°C in both air and nitrogen. 相似文献
1000.
Takashi Fujimoto Kiyoshi Ueda Kuniya Fukuda 《Journal of Quantitative Spectroscopy & Radiative Transfer》1979,21(1):89-91
For Ba perturbed by Kr, collision-induced dipole transitions 6s21S0 – 6snd1D2 (8?n?10) have been observed. The effective oscillator strength per unit Kr density was found to be 1.8–1.0 x 10-23 cm3. For the electric-quadrupole transition 6s21S0 -6s6d1D2, the oscillator strength is (2.0±0.4) x 10-6. 相似文献