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111.
Nakano K Suemura N Kawata S Fuyuhiro A Yagi T Nasu S Morimoto S Kaizaki S 《Dalton transactions (Cambridge, England : 2003)》2004,(7):982-988
The synthesis and characterization of new spin-crossover pyrazolato bridged dinuclear [(FeII(NCS)(py))2(mu-bpypz)2] and the corresponding cyanotrihydroborato-kappaN complexes are described together with the X-ray crystal analysis of the latter in both the high-spin and low-spin states as well as the variable temperature magnetic susceptibility and/or Mossbauer spectra demonstrating the spin-crossover which exhibits an one-step process, but not a two-step one characteristic of the known bpym bridged dinuclear complexes. 相似文献
112.
A method is described for the flotation an determination of ng-levels of cadmium in water. Cadmium in a 1-l sample of water is coprecipitated with hydrated zirconium oxide at pH 9.1 ± 0.1. The precipitate is floated with the aid of a surfactant solution and small air bubbles, separated and dissolved in dilute hydrochloric acid. The cadmium content is determined by electrothermal atomic absorption spectrophotometry. The method is applied to the determination of ng l?1 levels of cadmium in fresh water. The time required for preconcentration of cadmium from a 1-l sample is 20 min per sample, after 20 min stirring. 相似文献
113.
A new internal standard method for activation analysis has been developed. This method is characterized by that a suitable element present originally in the sample is used as an internal standard and the comparative standard is prepared by applying the standard addition method to the duplicated sample. When a sample under examination contains Wag of trace element A to be determined together with a known amount of element B which is usable as an internal standard, and when the comparative standard is prepared by adding W
a
*
g of accurately known small amount of the element A to the duplicated sample, even if the sample and comparative standard are irradiated separately by particles with different fluxes, Wa can be determined, easily by using the following equation: Wa=W
a
*
/[(A
R
*
/AR)-1] Where AR and A
R
*
are counting ratios of gamma-rays emitted by two radioactive nuclides produced from the element A and B in the sample and comparative standard, respectively. Neither correction of the inhomogeneities of flux between the sample and comparative standard, nor that of, the self-shielding effects are necessary for the present method. The usefulness of the method was examined through the determination of Co, Ni, Rb and Sr in pepperbush by means of photon activation, and the precision and accuracy of the method were proved to be valid. 相似文献
114.
Y. Shiokawa K. Suzuki M. Yagi S. Suzuki 《Journal of Radioanalytical and Nuclear Chemistry》1989,130(1):55-62
An internal conversion electron spectrometer with high energy resolution has been constructed by using a windowless Si(Li) detector. After its characteristics were examined fundamentally, it was applied to determine the240Pu to239Pu isotope ratio. As a result, the energy resolution realized was demonstrated to be satisfactory. 相似文献
115.
Y. Shiokawa K. Suzuki S. Suzuki M. Yagi 《Journal of Radioanalytical and Nuclear Chemistry》1990,143(1):135-141
The isotopic ratios240Pu/239Pu in plutonium samples purified freshly and allowed to stand for a long time were determined by using a high resolution internal conversion electron spectrometer. As a result, it was proved that the above ratios can be determined accurately and precisely. The method was also examined further through a similar determination with curium samples. 相似文献
116.
117.
Kinetics of NS (B2 Π → X2Π) emission produced by the reaction of active nitrogen with sulfur vapor or sulfur chloride (S2Cl2) has been studied as a function of the total pressure and of the concentrations of atomic nitrogen and sulfur. The B 2Π state of NS is selectively formed by the three-body recombination reaction of N ans S atoms, N(4S) + S(3P) + M →. NS(B 2Π) + M. The highest vibrational level of the B 2Π state observed is ν′ = 12, which gives a lower bound for the dissociation energy of 4.93 eV. 相似文献
118.
Yukako Saito 《Tetrahedron letters》2006,47(18):3099-3102
A very mild, BBDI-catalyzed esterification using approximately equimolar amounts of N-protected amino acids and alcohols, in junction with Boc2O is described. 相似文献
119.
Akiko Sekine Hidehiro Uekusa Yuji Ohashi Kimihiro Yoshimura Mikio Yagi Jiro Higuchi 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(12):1462-1464
The crystal structures of 4-nitro-9,10-dihydrophenanthrene, C14H11NO2, (I), and 4-nitrophenanthrene, C14H9NO2, (II), the latter having two crystallographically independent molecules, show that the molecules are not planar. The dihedral angles between the phenyl rings of the biphenyl skeletons are 28.64 (8)° for (I), and 10.34 (15) and 11.75 (13)° for the two molecules of (II). The differences in the dihedral angles have an effect on the photochemical reactivity of the molecules. 相似文献
120.
Takeshi Sakai Takehiko Yagi Ryosuke Takeda Toshiki Hamatani Yuki Nakamoto Hirokazu Kadobayashi 《高压研究》2020,40(1):12-21
ABSTRACTBoth micro-paired and conical support type double-stage diamond anvil cells (ds-DAC) were tested using a newly synthesized ultra-fine nano-polycrystalline diamond (NPD). Well-focused X-ray sub-micron beam and the conically supported 2nd stage anvils (micro-anvils) with 10?μm culet enable us to obtain good quality X-ray diffraction peaks from the sample at around 400?GPa. The relationship between confining pressure and sample pressure depends heavily on the initial height (thickness) of micro-anvils, the difference of a few micrometers leads to a quite different compression path. The conical support type is a solution to retain both enough thickness and strength of micro-anvils at higher confining pressure conditions. All conical support ds-DAC experiments terminated by the failure of the 1st stage anvil instead of 2nd one. The combination of ultra-fine NPD 2nd stage anvil and NPD 1st stage anvil opens a new frontier for measurement of the X-ray absorption spectrum above 300?GPa. 相似文献