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排序方式: 共有347条查询结果,搜索用时 12 毫秒
81.
Y. Uwamino T. Ishizuka H. Yamatera 《Journal of Electron Spectroscopy and Related Phenomena》1984,34(1):67-78
A variety of rare-earth (RE) compounds (oxides, sulfates and oxalates) have been studied by X-ray photoelectron spectroscopy. Except for Eu, the binding energies (BE's) of the RE 3d and 4d peaks for the sulfates and oxalates are respectively almost equal to and 1.3–3.1 eV higher than those for the oxides. In the Eu 3d spectrum of europium(II) oxalate, distinct shake-down satellite peaks are present, and the BE's of these peaks are 1̃0 eV lower than the parent ones. For the oxides, appreciable differences are found in the BE's of the O 1s peaks, and a specific “inclined W” form is observed in plots of BE versus 1/R (where R is the mean distance from the oxygen atom to the neighboring RE atom) and versus the RE oxidation-reduction potential (ORP). No characteristic differences are seen in the BE's (C 1s, S 2s and S 2p) of the other ligands. 相似文献
82.
We succeeded in strictly transparent wavelength conversion by means of channel selection from multi-wavelength signals generated by sinusoidal modulation of input signal. Modulation-format-independent and bit-rate-independent wavelength conversion is achieved with small power penalty. 相似文献
83.
84.
骆鹏 柳敏良 刘忠 张玉虎 周小红 郭应祥 马英君 Y.Sasaki K.Yamada H.Ohshima S.Yokose M.Ishizuka T.Komatsubara K.Furuno 《中国物理 C》2004,28(3):268-273
利用在束γ谱学技术,通过128Te(10B,1p3n)134Ba反应研究了134Ba的中、高自旋激发态.实验中采用9套BGO(AC)HPGe探测器进行了γγt符合测量.基于γγ符合关系、γ射线的相对强度和各向异性度的测量结果建立了134Ba的能级纲图.比较N=78的同中子素链的负宇称能级结构的系统性,发现激发能位于4142keV,Jπ值为11-的能级很可能是与136Ce具有相似内禀结构特征的相似态 相似文献
85.
T. Hashimoto F. Ishizuka Y. Yoneyama T. Kubota N. Fukuyama 《Journal of Radioanalytical and Nuclear Chemistry》1995,197(1):99-114
The time files due to radioactive decay events were analyzed for the selective extraction of successive alpha-decay pulse events in millisecond orders, such as216Po (145 ms, thorium series),217At (32.3 ms, neptunium series), and215Po (1.78 ms, actinium series) after respective preceding parents decay, using a multiple time interval analysis (TIA-MTA) technique from both theoretical and experimental viewpoints. In the theoretical treatments, the detection sensitivities of each correlated event in natural decay series was compared with more generalized conditions. It was noteworthy that the evaluated detection sensitivity had increased proportionally with shorter half-lives in the following order:214Po>215Po>217At>216Po.Finally, the present TIA was applied to the clarification of thorium series disequilibrium states in Tamagawa (Akita, Japan) Hot Spring waters. Activities of224Ra were evaluated to be 3.41±0.38 and 0.60±0.08 Bq/l at the upper and lower stream, respectively. The results from activity ratios of radium to thorium isotopes showed a preferential precipitation of radium isotopes in comparison with thorium, reflecting the sensitivity to the lowering acidity of strongly acidic hot spring waters in the lower end of the stream. 相似文献
86.
Saito N Matsunaga T Fujishima T Anzai M Saito H Takenouchi K Miura D Ishizuka S Takayama H Kittaka A 《Organic & biomolecular chemistry》2003,1(24):4396-4402
Novel 2[small alpha]-methyl-, 2[small alpha]-(3-hydroxypropyl)- and 2[small alpha]-(3-hydroxypropoxy)-substituted 25-dehydro-1[small alpha]-hydroxyvitamin D-26,23-lactone derivatives were efficiently synthesized Reformatsky type allylation and palladium-catalyzed alkenylative cyclization processes, and their biological activities were evaluated. Introducing functional groups into the 2[small alpha]-position of the vitamin D-26,23-lactones resulted in remarkable enhancement of their antagonistic activity on vitamin D receptor (VDR). 相似文献
87.
Masaaki Yoshifuji Tadao Ishizuka Yoon Jung Choi Naoki Inamoto 《Tetrahedron letters》1984,25(5):553-556
Diphenylphosphinothioyl compounds were ortho-lithiated and alkyldiphenyl phosphine sulfides were α-lithiated and the resulting lithio compounds reacted to give the corresponding - and α-substituted products. 相似文献
88.
Takayoshi Kobayashi Masakatsu Hirasawa Yuzo Sakazaki Hiroki Hane 《Chemical physics letters》2004,400(4-6):301-307
Ultrashort pulse lasers with 6- and 20-fs durations were utilized for phthalocyanine thin film sample to induce several vibrational modes and vibration amplitude spectra were determined by multi-wavelength measurement technique. From the spectra we could identify the electronic states, which couple to two vibrational modes with frequencies of 670 and 750 cm−1. It was shown that the vibrational amplitude profile obtained by the method can be used for providing information for the assignment of the vibrational mode. 相似文献
89.
A series of cellulose benzoates with different degrees of substitution (DS) were prepared by aminolysis under homogeneous conditions. Using them as a stationary phase, the dependence of the chromatographic chiral recognition of cellulose benzoate (CB) on its DS was studied under normal phase conditions. For most enantiomeric pairs, chiral recognition decreased along with the decrease in DS. However, some enantiomeric pairs were resolved only by CBs carrying unsubstituted hydroxyl groups. Many of the compounds were quite strongly retained by cellulose benzoate with a DS of 2.8. A study of the retention behaviors of simple achiral compounds led us to the conclusion that the change in the retention behaviors by introducing free hydroxyl groups into tribenzoate is not caused by hydrogen bonding including the hydroxyl groups, but by a specific unidentified change. 相似文献