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151.
K. G. Malmqvist G. I. Johansson K. R. Akselsson 《Journal of Radioanalytical and Nuclear Chemistry》1982,74(1-2):125-147
Specific advantages with Particle Induced X-Ray Emission are: its (1) multielemental capability, especially when combined
with nuclear techniques for lighter elements, (2) speed, (3) low detection limits for small samples and (4) accuracy. To make
full use of these advantages, analytical parameters have to be chosen optimally and the facility to be carefully designed.
This paper describes an experimental facility constructed to permit continuous development work to optimize the analytical
conditions and to allow the gradual implementation of automatic control. Emphasis is also put on the simultaneous use of proton
induced gamma rays from fluorine. The features and the performance of the set-up including its accuracy, precision and experimental
detection limits are reported. 相似文献
152.
Surface tension measurements were made on concentrated (<4 moles/kg) aqueous solutions of the following 1.1-electrolytes: KF, KCl, KI, HCl, and HNO3. Two different measurement techniques were used: the Wilhelmy slide method and a method based on the scattering of laser light by small amplitude liquid surface waves. The surface tension determined by the two methods agrees within ±0.5% and for each solution it is found to vary almost linearly with concentration. The shear viscosity was also measured for these solutions by means of the laser method and a standard flow viscosimeter. The measured values were found to agree within ±5%. 相似文献
153.
N G Johansson 《Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry》1976,30(5):377-382
The [(4-methoxycarbonylthiazolidino)carbonyl-dihalomethyl]phenylmercury compounds 2a,b and 5a,b have been synthesized. When heated in refluxing bromobenzene they form halogenated penicillin analogs. (--)-Methyl 6-epi-6-bromobisnorpenicillinate (3a) and methyl 6-epi-6-bromopenicillinates (6a,b) have been prepared and isolated. 相似文献
154.
T. Buran A. Eide P. Helgaker P. Lehmann A. Lundby A. Navarro-Savoy L. Staurset O. S?rum C. Baglin P. Briandet P. Fleury G. De Rosny J.M. Thenard P.J. Carlson K.E. Johansson B. DAlmagne F. Richard D. Treille V. Gracco 《Nuclear Physics B》1975,97(1):11-28
Antiproton-proton elastic scattering data at 6.2 GeV/c in the range 0.3 (GeV/c)2 ? ?t ? 10.0 (GeV/c)2 is presented. The experiment, using spark chambers and proportional chambers, was performed at the CERN Proton Synchroton.The dip at about ?t = 0.5 and the structure at about ?t = 2.2 (GeV/c)2 are equally strong at 6.2 GeV/c as they are at 5.0 GeV/c. The differential cross sections around 90° c.m. are not very different at 5.0 GeV/c and at 6.2 GeV/c, whereas in the backward region there is a decrease of the order of one magnitude. 相似文献
155.
A new approach to the determination of extraction constants is described. The aqueous and organic phases, the former containing the counter ion, are pumped continuously as small segments through an extraction coil. The sample ion is introduced into the aqueous phase before it enters the coil, where the ion-pair extraction takes place (during 20 s). After leaving the extraction coil, a certain fraction of the organic phase is pumped through the flow-cell of the spectrophotometer. The extraction constants are calculated by slope analysis from the experimental data (absorbance and counter ion concentration). The constants usually agreed within ±0.1 (log units) with values obtained from batch experiments. 相似文献
156.
A surface state seen in normal photoemission from TiN(001), at - 2.9 eV relative to the Fermi energy, is associated with the Δ5 band in the bulk band structure consisting of N px/py orbitals. As TiN is somewhat ionic, there is a change in the electrostatic potential at the surface and this is large enough to pull a Tamm surface state off the Δ5 band. 相似文献
157.
B. Johansson 《Solid State Communications》1974,15(8):1333-1335
From an adjustment of the parameters of the Lennard-Jones potential to fit the effective ion-ion interaction in the alkali metals, their critical volume and temperature are calculated. 相似文献
158.
Johansson A 《Talanta》1973,20(1):89-102
A detailed exposition is given of the use of logarithmic diagrams and Gran plots to construct titration curves and to determine accurately the equivalence point in potentiometric complexometric titrations. 相似文献
159.
The reactions and have been studied for proton energies between 163 and 186 MeV. Angular distributions for the ground states and the excited state at 2.13 MeV in 11B are presented. Cross sections calculated in the one-nucleon model, under different assumptions about the interaction Hamiltonian as well as the pion and proton optical potentials, are compared with the experimental distribution from the state in 41Ca. 相似文献
160.
Rapid and complete switching between the N6 and the N5O donor set induced by changing the metal oxidation state has been observed for a new structural motif based on a ruthenium(II) polypyridyl complex. 相似文献