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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
I. V. Stefanyuk E. L. Oleinikova L. G. Khodskii A. A. Sirotinskii E. K. Nazimova 《Glass and Ceramics》1993,50(3):112-116
Translated from Steklo i Keramica, No. 3, pp. 7–10, March, 1993. 相似文献
992.
D. A. Ivashintsov D. V. Stefanishin A. B. Veksler 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1995,29(4):227-234
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 4, pp. 30–35, April, 1995. 相似文献
993.
Summary Stability of a twisted and axially compressed elastic rod is analysed using the Euler method of adjacent equilibrium configuration. The constitutive equations of the rod are assumed in the form that takes into account both shear of the cross-sections and compressibility of the rod axis. It is shown that bifurcation points of the non-linear system of equations describing equilibrium are determined from the linearized system of equations. The influence of shear and compressibility on the critical values of twisting couple and compressive force is obtained. Moreover, the bifurcation pattern is examined by using the Liapunov-Schmidt method. 相似文献
994.
L. D. Monti P. E. Sandoli S. Costa V. C. Phan P. M. Piatti 《Journal of Automated Methods and Management in Chemistry》1993,15(5):177-181
Intermediate products of the metabolism of glucose, fat and amino-acid are important in the evaluation of such metabolic disorders as diabetes mellitus, liver disease and metabolic acidosis. In the present study, methods for the measurement of intermediate metabolites (lactate, pyruvate, alanine, β-hydroxybutyrate and glycerol) have been adapted to a fast centrifugal analyzer: the COBAS FARA. Correlation coeffcients rangedfrom 0.90 to 0.99, compared to established manual spectrophotometric methods. Within-run coeffcients of variation (CVs) ranged between 2.9 and 8.8% at low levels, between 1.5 and 5.7% at medium levels and between 1.2 and 5.6% at high levels. Between-run CVs were between 4.0 and 15.0% at low levels, between 1.7 and 7.0% at medium levels and between 1.3 and 2.7% at high levels. These fluorimetric assays for the determination of intermediate metabolites on COBAS FARA (Roche) have a good sensitivity and precision, are less costly than manual methods and can be used on a routine basis. 相似文献
995.
996.
A. A. Bochvar All-Union Scientific-Research Institute of Standardization in Machine Building. Translated from Atomnaya énergiya,
Vol. 76, No. 2, pp. 125–127, February, 1994. 相似文献
997.
N. I. Kolosnitsyn 《Measurement Techniques》1993,36(2):151-153
Translated from Izmeritel'naya Tekhnika, No. 2, pp. 24–25, February, 1993. 相似文献
998.
Oxygen nonstoichiometry in the distorted perovskite BaBiO3 has been studied by thermogravimetric analysis using controlled oxygen pressures. Three distinct regions of nonstoichiometry are observed with composition ranges which narrow as the temperature is lowered. Samples isolated from each region were shown by powder X-ray diffraction to retain the perovskite subcell but show different types of framework distortion. Low temperature reoxidation of the oxygen deficient phases is also described. 相似文献
999.
1000.