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91.
92.
K. Bangert U.E.P. Berg G. Junghans R. Stock K. Wienhard H. Wolf 《Nuclear Physics A》1976,261(1):149-173
The electric giant dipole resonance of 24?26Mg has been explored up to 30 MeV excitation energy with bremsstrahlung. ΔE, E spectra of charged photo-particles and spectra of prompt deexcitation γ-rays from excited residual nuclear states were obtained at various bremsstrahlung endpoint energies. The 25Mg(γ, p0), (γ, d), 24,25Mg(γ, α) differential cross sections as well as 24?26Mg(γ, xγ′) integrated cross sections are presented. The results are discussed in terms of one-particle, one-hole excitations and isospin composition of giant resonance states. A comparison with calculations for 24Mg gives poor agreement. Excitations from deeper shells were found in the giant dipole resonance of 24Mg, but do not seem to be concentrated at higher energies. In 25Mg, only weak excitations of this kind were found, and they are completely absent in 26Mg. 相似文献
93.
J.G. Wijmans S. Nakao J.W.A. Van Den Berg F.R. Troelstra C.A. Smolders 《Journal of membrane science》1985,22(1):117-135
The influence of concentration polarization on the permeate flux in the ultrafiltration of aqueous Dextran T70 solutions can be described by (i) the osmotic pressure model and (ii) the boundary layer resistance model. In the latter model the hydrodynamic resistance of the non-gelled boundary layer is computed using permeability data of the Dextran molecules obtained by sedimentation experiments. It is shown both in theory and experiment that the two models are equivalent. 相似文献
94.
The activation area for the motion of dislocations is deduced by means of thermodynamic theory of the transition state. Assuming an exponential dependence of the slip velocity as a function of the applied stress and using additional simple statements the activation area is obtained in terms of parameters, which can be determined experimentally. Further on it is shown that one has to distinguish between different definitions of the activation area. 相似文献
95.
Abstract— As previously demonstrated, there is a considerable increase in the photodynamic activity of anthraquinone-sulphonic acid on the addition of ethylene glycol, glycerol and sugars in concentrations of the order of 0.4 M . This system exhibits cytostatic activity. With H2 O2 at higher concentrations there is also formation of aldehydes in approximately equivalent yields as follows:
R.CH2 OH+Q → QH2 +R.CHO
QH2 +O2 → Q+H2 O2
In accordance with the recent results of Warburg this accounts for the fundamental importance of glyceraldehyde in cancer research.
Our results on the irradiation of Proteus vulgaris SG2 in buffered medium with the addition of glycerin to anthraquinone-sulphonic acid show the existence of a similar cytostatic effect. One hour's irradiation with visible light reduces the cell count by about 50 per cent. 相似文献
R.CH
QH
In accordance with the recent results of Warburg this accounts for the fundamental importance of glyceraldehyde in cancer research.
Our results on the irradiation of Proteus vulgaris SG2 in buffered medium with the addition of glycerin to anthraquinone-sulphonic acid show the existence of a similar cytostatic effect. One hour's irradiation with visible light reduces the cell count by about 50 per cent. 相似文献
96.
97.
It is proved that the space of functions constant on vertical lines is not complemented in the space of all measurable functions
on the unit square (with the topology of convergence in measure). The analogous results is proved for the space of all measurable
functions on the product of two probability spaces, one of which is atomless.
This research was partially supported by National Science Foundation grant N.S.F. GP 28577. 相似文献
98.
99.
100.
In Taylor-Couette flow the total energy dissipation rate and therefore the drag can be determined by measuring the torque on the system. We do so for Reynolds numbers between Re=7 x 10(4) and Re=10(6) after having injected (i) small bubbles (R=1 mm) up to a volume concentration of alpha=5% and (ii) buoyant particles (rhop/rhol=0.14) of comparable volume concentration. In case (i) we observe a crossover from little drag reduction at smaller Re to strong drag reduction up to 20% at Re=10(6). In case (ii) we observe at most little drag reduction throughout. Several theoretical models for bubbly drag reduction are discussed in view of our findings. 相似文献