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971.
T.G.M. van de Ven 《Advances in colloid and interface science》1982,17(1):105-127
Recent progress in experimental and theoretical developments dealing with colloidal. interactions between two spheres in shear flow is reviewed. A systematic comparison is made between spheres suspended in simple electrolyte and in cationic polyelectrolye solutions. Microrheological observations, performed with the traveling microtube, make an in-depth investigation possible of the colloidal forces and the mechanisms of polymer bridge formation. Reasons are discussed for the often-observed aging of colloidal aggregates. Finally, coagulation rates are presented for systems with weak and strong Brownian motion. It is shown that the often-used assumption of additivity of the ortho- and perikinetic coagulation rates is incorrect. 相似文献
972.
Problems in scaling-down procedures of chemical analysis are generally stated. Titrations are to be preferred over single measurements. Continuous titration in a titration system may help in solving the stated problems. Detection is easy and may be done by simple electrodes. Illustrations from the authors' practice are given. 相似文献
973.
974.
975.
G.W. van Apeldoorn D. Harting D.J. Holthuizen B.J. Pijlgroms M.M.H.M. Rijssenbeek V. Karimäki R. Kinnunen M. Korkea-Aho J. Maalampi J. Tuominiemi G.D. Patel P. Johnson P. Mason H. Muirhead B.M. Whyman 《Physics letters. [Part B]》1982,115(1):55-58
Data on the density of charged particles in rapidity space for annihilation and non-annihilation p?p interactions at 7.3 and 12 GeV/c are reported. It is shown that the central rapidity density for non-annihilation processes is a simple linear function of from these low energies up to p?p collider energies (). Significant differences in density distributions for p?p and e?e+ annihilations at comparable energies are found. 相似文献
976.
Analysis of the γ-ray angular distributions measured at 16 36S(p, γ)37Cl resonances yields the spins and/or parities of 21 bound states of 37Cl in addition to the resonance spins. Among the latter are four resonances. For several other bound states the possible spins have been restricted. Multipolarity mixing ratios have been deduced from the same data. Lifetimes (or lifetime limits) of 29 bound states have been deduced from DSA measurements.This extensive experimental information allows a comparison with the results of a shell-model calculation for both the even- and odd-parity states of 37Cl. In this calculation either zero, one or two particles are promoted from the 2s or 1d to the 1f or 2p subshells. Up to an excitation energy of about 5 MeV a one-to-one correspondence is found between experimental and calculated levels. 相似文献
977.
978.
A further analysis of previous reported measurements of dielectric relaxation losses in lead chloride and lead bromide crystals shows that the dipoles may occupy several energetically different positions, giving rise to localization of the dipoles and anomalous behaviour of the susceptibility. This energy difference is determined. Inspection of the crystal structure shows that the anion vacancy, being the mobile part of the dipole (which is an associate like (MePb·VX)x or (OX·VX)x where X = Cl, Br), may jump indeed between halide ion sites with different coordination number.A comparison between the dipole concentration as calculated from the observed losses and the associate concentration as estimated from ionic conductivity experiments leads to the conclusion that local field corrections in the calculations are important. 相似文献
979.
An important limitation to the sensitivity of analytical methods using atomic spectroscopy is the short residence-time of the atoms in the light-path. The possibility has been studied of sealing the samples in a quartz tube where they are forced to emit light by microwave excitation. The detection of amounts below one ng in a volume of 0.5 ml seems possible. 相似文献
980.