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91.
A simple low-cost flow-through light-scattering detector was developed for determining the particle mass concentration in colloidal suspensions. Employing a laser pointer as a light source and a photodiode IC as a light sensor, the detector was shown to have good sensitivity, yet was small and battery operated. The detector was demonstrated to be effective for the flow-injection nephelometric determination of sulfate by precipitation as barium sulfate.  相似文献   
92.
93.
Within the framework of the IBA model, α-spectroscopic factors are presented for the Te(d, 6Li)Sn and Sn(d, 6Li)Cd reactions. It is shown that inclusion of higher order terms in the boson-fermion mapping is essential in predicting the correct systematics for 2+1 excitation.  相似文献   
94.
Summary A general and easily applied expression is derived for the force on an accelerating body in an axisymmetric slow viscous flow. This expression is valid for any axisymmetric body, irrespective of the conditions at the surface.
Résumé Une expression, générale et facile à appliquer, est derivée pour la force sur un corps qui est soumis à une accélération dans un écoulement lent, visqueux et axisymétrique. Cette expression est valable pour n'importe quel corps axisymétrique, indépendamment des conditions à la surface.
  相似文献   
95.
Summary We apply spline methods to the problem of calculating continuum excitation probabilities of molecular systems under the influence of electromagnetic fields. Numerical results are given for the H 3 + molecular ion.  相似文献   
96.
The well-known Maxwell-Vlasov equations that describe a collisionless plasma are cast into hamiltonian form. The dynamical variables are the physical although noncanonical variables E, B and f. We present a Poisson bracket which acts on these variables and the energy functional to produce the equations of motion.  相似文献   
97.
98.
A non-relativistic perturbation method of Brueckner-Goldstone type is used to calculate the hyperfine interactions in the lowest2 S and2 P states of the Li-like systems, Li, Be+, B2+, C3+, N4+, O5+ and F6+. The effect of the polarization of the closed shell is treated to all orders of perturbation, while the correlation effect is calculated in the lowest order, i.e. in the third order of the perturbation expansion. Experimental data are at present available only for Li, Be+ and F6+, and the agreement with the calculated values is in these cases very good, usually within the experimental uncertainties. This implies that the predictions made in the remaining cases should be quite reliable, which may simplify the experimental determination of these quantities. Theoretical values are also given for the quadrupole interaction, which can be used to determine the nuclear quadrupole moments, when accurate experimental information becomes available.  相似文献   
99.
Abstract. The role of protein synthesis in liquid-holding recovery from ultra-violet radiation damage in synchronized Saccharomyces cerevisiae cells has been studied using cycloheximide as a specific inhibitor of cytoplasmic protein synthesis. Liquid-holding recovery from UV-induced budding delay is completed within a few hours and is not inhibited by the presence of cycloheximide. Liquid-holding recovery from lethal UV damage is unaffected by cycloheximide for liquid-holding times less than about 12 h. For longer times recovery is inhibited, with survival enhancement eliminated after about 48 h. Periods greater than 48 h of liquid-holding in the presence of cycloheximide result in survival less than that obtained with immediate plating, but the same concentration of cycloheximide is not toxic to unirradiated cells.  相似文献   
100.
The production of KS0, Λ andΛ is measured in π+p reactions at 16 GeV/c. The total strange particle cross section is found to be 4.0 ± 0.3 mb, about 20% of the inelastic cross section. Cross sections for single strange particles and for strange particle pairs are determined, both inclusively and as functions of the charged multiplicity. Relative production rates for different strange particle combinations are compared with the prediction of the isospin statistical model. Inclusive spectra for single particles are studied and it is found the KS0 are produced mostly in the forward hemisphere, most probably by fragmentation of the incident pion into KKπ. The Λ are mostly backwards, probably deriving from fragmentation of the proton into ΛK pairs. The Λ tend to be produced forwards, but evidence is found for central ΛΛ production. Distributions in rapidity of the Λ particles from π+p interactions are compared in terms of the factorisation hypothesis. Results are given on the Λ transversal polarisation.  相似文献   
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