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931.
Evaporation-residue excitation functions for16O and12C+197Au reactions were measured by means of the activation technique. The competition between evaporation and fission of the compound nuclei was studied by comparing the observed evaporation-residue data with the published fission excitation functions. A newly devised analysis was applied in order to deduce a fission barrier height at a specified angular momentum and determine the relevant fissioning nucleus as well. We found the fission barriers to be 8.2 MeV for the211Fr nucleus at 16? and 8.2 MeV for the207At nucleus at 27?.  相似文献   
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935.
Cyanide is separated from biological bluids by microdiffusion using 1 M acetate buffer (pH 5.2) as an acidifying agent, followed by the fluorimetric determination of the cyanide with naphthalene-2,3-dialdehyde and taurine. The recovery and limit of detection of cyanide in blood and urine are about 70–80% and 0.03 nmol ml?1, respectively. The proposed method for cyanide was successfully adapted for application to blood and urine from smokers and non-smokers.  相似文献   
936.
937.
A simple method to estimate the amounts of ultra-trace metal impurities in nitric acid reagents has been developed. The determination of sixty-four metals in nitric acid was accomplished by direct measurements of 0.1 M nitric acids accurately diluted with ultrapure water by ICP-MS. Though accurate metal concentration could not be obtained for all of the elements, we could effectively evaluate the nitric acid quality by comparing the ion counts of the samples, ultrapure water and standard metal solutions for a calibration prepared with Ultrapur nitric acid.  相似文献   
938.
The concept of Multi-stage indirect cooling and Radial Flow (MRF) is ideal for designing a catalytic reactor in which an exothermic equilibrium reaction takes place. The reaction is controlled to go on along the path of the maximum reaction rate in the catalyst bed where synthesis gas flows radially in the catalyst beds from the outer side to an inner center pipe across boiler (cooling) tubes to recover the reaction heat as qualitative steam. The MRF concept has already been proven in a commercial scale methanol plant and is unique not only for saving energy but also for considerable scale-up for which the enhanced design, MRF-Z®, provides. MRF-Z® is now offered for single train 5,000 t/d reactors used in so-called jumbo methanol plants.  相似文献   
939.
Hydrogen adsorbed on a Si(100) surface can be detected by angle-resolved LEIS (low-energy ion scattering spectroscopy) which uses a 4He+ ion beam with incident energies around 1 keV. The scattering peaks from the surface hydrogen are restricted to narrow scattering angles from 0° to 15°, which is in agreement with those expected by the binary elastic collision model.  相似文献   
940.
2,4-Dienoate was prepared by pyrolysis of 2-(phenylsulfinyl)enoate. N-Isobutyl-E,E-2,4-decadieneamide (pellitorine) was synthesized from decanoic acid in a satisfactory yield.  相似文献   
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