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991.
Antibodies raised against progesterone with hormone-carrier protein bridges placed at four different carbon positions were used to compare the sensitivity and specificity of homologous and heterologous enzyme-hormone conjugates. All heterologous assays were at least twice as sensitive as the corresponding homologous assays. The best results were obtained by using antibodies against 7 alpha-carboxyethyl-thioether-progesterone with 6 beta-hemisuccinate-progesterone conjugate (or hemimaleate). The sensitivity with human sera was 0.25 ng ml-1 and, the highest crossreaction 10% with 5 beta-pregnane-3,20-dione, and reproducibility, recovery and accuracy were satisfactory. The correlation coefficient with radioimmunoassay in 103 human sera tested was r = 0.915. The assay was successfully applied for the diagnosis of pregnancy in dairy cattle.  相似文献   
992.
993.
The structure and properties of solid solutions and the chemical compound Gd2Zr2O7 in the Gd2O3 - ZrO2 system are investigated. Sintering of the initial mixture is studied and the optimum concentration of the stabilizing additive is determined for the production of heat-resistant articles from granular mixtures based on ZrO2 stabilized by Gd2O3 and fired at 1750°C. Properties of specimens prepared by the technology developed are presented. Translated from Ogneupory, No. 3, pp. 12 – 16, March, 1996.  相似文献   
994.
Direct volume display devices (DVDDs), which display 3D volumes and surfaces in a volume by providing depth rather than depth cues, are discussed. The transport theory model is used to illustrate why DVDDs are best able to support fast presentation from arbitrary directions. The technology underlying various DVDDs is described. Specifically, the design and operation of the OmniView rotating-screen DVDD are examined. The air-traffic-control/air-tactics-analysis, satellite orbit mechanics, and time-critical target prosecution applications of DVDDs are also discussed  相似文献   
995.
Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 89–99, November–December, 1993.  相似文献   
996.
An example of an opto-pneumatic detector's (OPD) frequency transfer function is presented for the development of an opto-pneumatic interface. The theoretical model is tested through experiments in the laboratory on a real OPD prototype. In this way many of the model's parameters are studied and evaluated, such as the dimensions of the gas chamber, the thickness of the absorbent body, and the load of the OPD. The results obtained are good and show the utility of the studies described here.  相似文献   
997.
An experiment to determine the effect of gate electrode resistivity on circuit speed gave unexpected results: circuits with the lowest sheet resistance had the poorest circuit speed. Explanation of this behaviour required development of a new high-frequency method of measuring the impedance of the gate electrode. This method revealed that the circuits with a composite gate electrode had been formed with a partial discontinuity. The measurement technique is described, and the evidence of the discontinuity is shown. The effect of the discontinuity on device and circuit speed is demonstrated  相似文献   
998.
A method for detecting shorted windings in operational turbine-generators is described. The method is based on the traveling wave method described by El-Sharkawi, et. al. (1971). The method is extended in this paper to operational rotors by the application of a neural network feature extraction and novelty detection. The results of successful laboratory experiments are also reported  相似文献   
999.
We have investigated the deformation of a rectangular plate half-embedded in an elastic base and subjected to a mechanical load. Using the apparatus of generalized functions, the problem is reduced to a system of singular integral equations which is solved by the boundary element method. We present the results in the form of isolines of the components of the displacement vector.Translated from Problemy Prochnosti, No. 3, pp. 72–77, March, 1996.  相似文献   
1000.
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