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101.
G.D. Wignall R.W. Hendricks W.C. Koehler J.S. Lin M.P. Wai E.L. Thomas R.S. Stein 《Polymer》1981,22(7):886-889
A series of small angle neutron scattering measurements on blends of normal polystyrene (PSH) and labelled (deuterated) polystyrene (PSD) have been made with concentrations of PSD from 5 to 50 mol %. It is shown that the single chain form factor of the polymer in bulk can be obtained from a single concentration measurement for any concentration of labelled molecules, providing the molecular weights of the parent and labelled molecules are the same and the molecular weight distributions are narrow. 相似文献
102.
Rapeseed protein concentrate (RC), prepared with 2% hexameta-phosphate, was tested for its functionality and performance in some foods. The RC had good nitrogen solubility, fat absorption, emulsification, and whipping capacities but poor water absorption and gelling properties. It increased the emulsion stability, and protein but lowered the fat content of wieners. It also increased the cooking yield, reduced the shrinkage and tenderized meat patties. Results were similar to soybean isolate except for the poorer color and flavor. The cooking yield of RC supplemented wieners was less than the all-meat control and soybean-supplemented wieners. A 9% RC dispersion mixed with an equal volume of eggwhite produced a meringue of comparable stability and texture to that of eggwhite alone. 相似文献
103.
The dynamic and equilibrium swelling behavior of polystyrene microparticles crosslinked with divinyl benzene was investigated in methyl ethyl ketone and cyclohexane. The dynamic studies gave new information about the mechanism of penetrant transport in this polymer. The equilibrium studies were used to determine important parameters of the crosslinked structure of these systems, including the average molecular weight between crosslinks, M?c 相似文献
104.
Translated from Atomnaya Énergiya, Vol. 66, No. 6, pp. 423–424, June, 1989. 相似文献
105.
A. A. Konstantinov N. V. Kurenkov A. B. Malinin T. E. Sazonova S. V. Sepman 《Atomic Energy》1989,67(3):696-698
Translated from Atomnaya Énergiya, Vol. 67, No. 3, pp. 215–216, September, 1989. 相似文献
106.
L. GbahoueF. Barbeu S. Martemianov 《International Journal of Heat and Mass Transfer》2002,45(18):3865-3873
Electrochemical method is applied to study coherent structures in a complex three-dimensional flow generated by a rotating magnetic rod. In order to detect these structures, the power spectral density (PSD) analysis of the limiting diffusion current fluctuations is provided. This analysis reveals the existence of resonance frequencies when the probe is located in the very vicinity of the stirrer. The main resonance is related to the mechanical excitation frequency. The detailed analysis of the PSD curves points out some mechanisms of development of turbulence as sub-harmonics and non-linear interactions. For different locations of the probe and different angular rates of the stirrer Ω, a similarity of the energy repartition is obtained when the PSD is plotted versus the adimensional frequency f/Ω. Flow visualization by laser tomography is also provided and the local secondary flow past the electrode probe is sketched. The laser Doppler velocimetry (LDV) at a given location in a horizontal z-plane indicates a tornado wise mean flow structure. 相似文献
107.
A.S. Fraser 《Journal of Great Lakes research》1980,6(1):83-87
An apparent decrease in total phosphorus concentrations of approximately 4.l μgP/L has been reported recently for the spring values of 1977 and 1978 in Lake Ontario. Investigation of the loading reduction for this period independent of sedimentation factors can account for only 10% of the change. The results indicate that changes in the sedimentation rate of total phosphorus during this period offer an explanation for the majority of the change in concentration. 相似文献
108.
Banded textures produced in a thermotropic liquid crystal polymer by shearing between glass slides are examined by using both transmission electron and polarized light microscopy. The periodic variation in director orientation about the shear axis, as measured by light microscopy, is shown to be distinctly different from that indicated by electron diffraction. Measurements of birefringence and observation of Zernicke phase contrast indicate periodic variations in optical properties of the polymer, in step with the bands. Such effects are accounted for in terms of a synchronous rotation of the planar aromatic groups about the molecular chain axes. Evidence for an out-of-plane component of molecular orientation is also presented. 相似文献
109.
A simple apparatus for elongational test of molten polymers is presented. Its realiability is demonstrated by means of stress growth in constant stretching rate experiments and relaxation test on a low density polyethylene sample. 相似文献
110.
K. A. Abdikalikov V. K. Zadiraka O. S. Kondratenko S. S. Mel'nikova 《Cybernetics and Systems Analysis》1991,27(3):414-419
A fast algorithm is proposed for estimating the auto- and cross-correlation functions of a large signal. The algorithm is based on the sectioning method by the fast Fourier transform. We determine the optimal length of the portion of data read from external memory into RAM which achieves Tmin—a minimum processing time. An estimate of Tmin is obtained.Translated from Kibernetika, No. 3, pp. 78–81, May–June, 1991. 相似文献