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971.
972.
I. Fromhold-Treu und W. Kozerke: A survey on digital picture processing in food science. Part 1. Determination of geometrical properties of isolated objects The aim of this series of articles is a summary of procedures and methods of the digital picture processing with the point of view of their special application in the science of nutrition and food. After a short introduction to the fundamentals of the digital picture processing some effective procedures of the recognition of isolated objects in binary pictures are given. Furthermore there are defined geometrical properties for these objects. 相似文献
973.
974.
975.
Crystallite growth characteristics of coprecipitated superfine zirconia powders have been investigated. It was found that the crystallite growth in powders follows a cubic law at 800 and 1000°C; however, the crystallite size data for compacts of both Y-TZP and YSZ cannot be fitted with a traditional parabolic or cubic law, but with a linear relation between crystallite size and the logarithm of time. In addition, it was also found that the degree of agglomeration of the powders can affect the crystallite growth. 相似文献
976.
L. Juul Thomsen T. Sch fer J. M. Sonnergaard H. G. Kristensen 《Drug development and industrial pharmacy》1993,19(15):1867-1887
A melt pelletization process was investigated in an 8 litre laboratory scale high shear mixer using a formulation with paracetamol, glyceryl monostearate 40-50, and microcrystalline wax. The effects of jacket temperature, product temperature during massing, product load, massing time and impeller speed were investigated by means of factorially designed experiments. The maximum yield of pellets in the range of 500-1400μm was found to approx. 90%. For process conditions preventing deposition of moist mass, the process was found to be reproducible. Impeller speed and massing time were found to be important process variables. Remarkably low in vitro drug release rates were observed in USP-dissolution tests. 相似文献
977.
PURPOSE: To evaluate the accuracy of measuring intraocular pressure by handheld non-contact applanation tonometer. METHOD: 58 patients' (113 eyes) intraocular pressure were measured by Keeler, non-contact tonometer and R 900 Goldmann applanation tonometer and the results of measurement of intraocular pressure by the two kinds of tonometers were compared. RESULT: The mean intraocular pressure measured by non-contact is 16.31 +/- 5.59 mmHg and 17.49 +/- 6.13 mmHg (1 mmHg = 0.1333 kPa) by Goldmann applanation tonometer, respectively. There was no statistical significance to be found (P > 0.05) between the two methods. By linear correlation and regression analysis, a positive correlation was found between the two methods (r = 0.8942, b = 0.8154). CONCLUSION: The handheld non-contact tonometer has the same accuracy and reliability of measurement of intraocular pressure comparing with Goldmann applanation tonometer, and it can be used in glaucoma clinic and screening. 相似文献
978.
A. S. Aleksandriiskii T. V. Druzhinina P. A. Gembitskii M. O. Lishevskaya L. S. Gal'braikh 《Fibre Chemistry》1991,23(1):29-33
Conclusions -- The reaction of guanidine with grafted polyglysodylmethacrylate has been investigated. Basic kinetic parameters of the process have been determined.-- Fibrous chemisorbents have been prepared based on graft PCA-PGMA or Cell-PGMA copolymers which have been aminated with guanidine; the content of amino nitrogen was up to 2% by wt.Translated from Khimicheskie Volokna, No. 1, pp. 29–31, January–February, 1991. 相似文献
979.
980.
Results of computational experiments carried out on an adaptation of the AEP/IEEE 30 bus test system are reported. Some selected buses were modeled using an exponential type of load model. Three cases are considered. In the first case it is assumed that the specified load at modeled buses is obtained with unity voltage. In the second case it is assumed that the transformer taps have been adjusted to give all industrial-type consumers one per unit at the low-voltage panel when the high-side voltage corresponds to the standard optimal power flow (OPF) solution. The third case differs from the second in that the specified power demand is assumed to take place when the high-side voltages correspond to the intact case of the standard security constrained OPF solution. It is concluded that a decrease in fuel cost can be obtained in some instances when load models are incorporated in security constrained OPF studies during contingencies only. In situations where a decrease in fuel cost is obtained in this manner, the magnitude of decrease depends on the total percentage of load fed by fixed tap transformers and the sensitivity of these loads to modeling 相似文献