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排序方式: 共有7562条查询结果,搜索用时 31 毫秒
941.
Masuo Suzuki 《Communications in Mathematical Physics》1977,57(3):193-200
The convergence of the Zassenhaus formula is proven under an appropriate condition as well as for other exponential operators such as the Baker-Campbell-Hausdorff formula.On leave of absence from Department of Physics, Faculty of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, Japan 相似文献
942.
943.
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945.
B. Kojić-Prodić M. Tonković O. Hadžija V. Kovač 《Analytical and bioanalytical chemistry》1976,279(5):359-362
For the cyanide determination in waste waters containing more than 2.5×10?6 Mol of CN?/l a conductometric method has been proposed. The sulphuric acid containing samples were distilled and the obtained HCN was passed into a 5×10?4 Mol/l AgNO3 solution, of which the conductivity was measured. The method offers the possibility of a precise observation of the completion of the HCN distillation and also the direct measurement of the cyanide concentration by the change of conductivity. The analysis time is about 40 min. 相似文献
946.
The reflection of a pulse by multiple-dielectric layers is treated theoretically. The reflected wave is obtained by expanding the reflection coefficient of an elementary plane wave in a series, including the special case for which total reflection occurs. The pulsed waves reflected by two-dielectric slabs are considered in detail both analytically and numerically. The effect of a carrier frequency of a pulse-modulated carrier wave on the reflected wave form is also discussed. 相似文献
947.
948.
Improvement of low-temperature performance of oxygen sensor was studied by preparing a thin film of 15 μm thickness. Melt-quenched Bi2O3 film doped with 16 mol% MoO3 was used as an electrolyte after HF treatment. Impedance measurements were carried out in the frequency range DC-100 KHz. Resistance of electrolyte in the form of thin film (110ω) was negligibly small compared with the overall resistance of the cell (287 Kω) at 350°C. Oxygen/air concentration cell was constructed and the cell performance was measured at 350 and 300°C. Transference number close to unity and rapid response were observed at 350°C, however the cell showed a long response time of about 3 min at 300°C. 相似文献
949.
H Yamabayashi M Izumo R Motoki T Yamamoto H Nishida S Shin K Sato Y Suzuki 《Radioisotopes》1985,34(3):144-150
A technique for the blood volume measurement of newborns was established in which nonradioactive 50Cr was used in patients for whom radioactive labels were not advisable. The red blood cells (RBC) in the newborn's blood withdrawn from umbilical cord after birth were tagged with enriched stable isotope 50Cr (96%, normal abundance 4.3%) and reinjected into the newborn. Blood samples (0.5 ml) were withdrawn at 30 min and thereafter at 6, 12, 24, 48, 72 and 120 hours old. Samples were centrifugalized and portion of RBC was then freeze-dried, weighed and sealed into polyethylene sheet bag together with 50Cr standard. Neutron irradiation was performed in the reactors of the JAERI with thermal neutron flux 5 X 10(13), 2 X 10(13), 8 X 10(13) cm-2s-1 at JRR-2, -3 and -4 respectively for 20 min and samples were left for about two weeks after irradiation. Induced radioactivity (51Cr, 59Fe) of the sample was measured with a Ge(Li) gamma-ray detector system and 4096 channels pulse height analyzer. Analysis of activity data was carried out by BOB-76 code. The RBC and total blood volume of the newborn was calculated using an isotopic dilution technique. We have investigated on tagging efficiency of 50Cr to RBC, washing effect and dilution rate by 50Cr content or 51Cr/59Fe ratio. Significant difference was observed in the total blood volume of newborns depending on the delivery style and in addition, it changed dynamically along the time elapsed after birth. 相似文献
950.