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951.
L. B. Getsov A. Ya. Madorskii N. N. Mozzhukhina A. G. Tereshchenko E. E. Yushchenkov 《Strength of Materials》1989,21(1):92-98
Leningrad. Translated from Problemy Prochnosti, No. 1, pp. 71–76, January, 1989. 相似文献
952.
Institute of Strength Problems, Academy of Sciences of the Ukrainian SSR, Kiev. Sumy Branch, Khar'kov Polytechnic Institute. Translated from Problemy Prochnosti, No. 8, pp. 102–104, August, 1989. 相似文献
953.
Static light scattering was used to investigate dilute dispersions of fine gamma -Fe/sub 2/O/sub 3/ magnetic particles. The particles were acicular and on average 0.39 mu m long and 0.056 mu m in diameter. They were dispersed in organic solvents at concentrations of approximately 10/sup -4/ vol%, corresponding to an average interparticle separation of 9 mu m. Computer programs using a coupled dipole algorithm to predict the scattering from the particles were written. Experimental results do not agree with computer calculations of the light scattering from single particles, but are consistent with scattering from thick ropelike agglomerates of particles. The size of these agglomerates was estimated after 10 s to be less than 100 particles, while the thickness of the ropes is at least 5 particles.<> 相似文献
954.
R. A. Mustafaev D. K. Ganiev D. M. Gabulov 《Journal of Engineering Physics and Thermophysics》1985,48(2):241-242
Dynamic-viscosity measurements are reported for liquid mixtures in the system formed by n-butyraldehyde and isobutyraldehyde.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 48, No. 2, pp. 321–322, February, 1985. 相似文献
955.
956.
N Paster J Blumenthal-Yonassi R Barkai-Golan M Menasherov 《International journal of food microbiology》1991,12(2-3):157-165
The production of zearalenone by an isolate of Fusarium equiseti was studied in chemically defined medium and in corn grains stored under modified atmospheres. An increase in the concentrations of sucrose or xylose in Czapek's medium resulted in increased toxin production, while no toxin was produced when lactose was present in the medium. Methionine (10(-2) and 10(-3) M) and cystine (10(-3) M) added to Czapek's medium inhibited zearalenone production. When amino acids or nitrogen salts were added as the sole nitrogen source, only alanine, tryptophan and NH4Cl totally inhibited zearalenone production. Zearalenone production was inhibited almost completely in high-moisture corn grains (27%) kept under atmospheres enriched with high CO2 levels (60%, 40% or 20%) with either 20% or 5% O2. However, a lower amount of CO2 was needed to inhibit fungal development and toxin formation when a reduced O2 level was applied. 相似文献
957.
Crystallization of some anorthite-diopside glass precursors 总被引:2,自引:0,他引:2
C. Leonelli T. Manfredini M. Paganelli P. Pozzi G. C. Pellacani 《Journal of Materials Science》1991,26(18):5041-5046
Anorthite and diopside have been obtained from complete devitrification of glasses belonging to the quaternary system MgO-CaO-Al2O3-SiO2. Microstructure, the natural trend of the nucleation mechanism and kinetic studies on the crystallization phenomenon have been investigated by means of optical and electron microscopies, thermal and thermomechanical techniques and X-ray powder diffractometry. All the glasses investigated show a complete crystallization starting from a simple surface nucleation process. The activation energy for the crystallization process proved to be higher than that for viscous flow, leading to an important aspect modification in the sample during ceramization. Thermal stability and physical properties of both glass and glass-ceramic materials have been tested, suggesting the possible use of these materials in industrial application. 相似文献
958.
Elastic stress concentration in a manipulator element is calculated within the framework of the two-dimensional stressed state model. The purpose here is to make recommendations for selecting the radius of joining of the beam parts of the element based on analysis of maximum stresses in the stress concentration zone. Combination of the finite element and boundary element methods is proposed for solving the problem. A coarse finite element subdivision is used for the initial calculation for the entire element. Then, the solution is refined by using boundary elements in the identified zone. Comparison of calculation results with solutions obtained by the finite element and boundary element methods points to the effectiveness of the proposed algorithm for stress concentration calculations.Translated from Problemy Prochnosti, No. 6, pp. 72–74, June, 1991. 相似文献
959.
V. Vassilev S. Thijs P. L. Segura P. Wambacq P. Leroux G. Groeseneken M. I. Natarajan H. E. Maes M. Steyaert 《Microelectronics Reliability》2005,45(2):255-268
This paper describes an approach to design ESD protection for integrated low noise amplifier (LNA) circuits used in narrowband transceiver front-ends. The RF constraints on the implementation of ESD protection devices are relaxed by co-designing the RF and the ESD blocks, considering them as one single circuit to optimise. The method is applied for the design of 0.25 μm CMOS LNA. Circuit protection levels higher than 3 kV HBM stress are achieved using conventional highly capacitive ggNMOS snapback devices. The methodology can be extended to other RF-CMOS circuits requiring ESD protection by merging the ESD devices in the functionality of the corresponding matching blocks. 相似文献
960.
During large scale wildfires, suppression activities are carried out under the direction of an Incident Management Team (IMT). The aim of the research was to increase understanding of decision processes potentially related to IMT effectiveness. An IMT comprises four major functions: Command, Operations, Planning, and Logistics. Four methodologies were used to study IMT processes: computer simulation experiments; analyses of wildfire reports; interviews with IMT members; and cognitive ethnographic studies of IMTs. Three processes were important determinants of IMT effectiveness: information management and cognitive overload; matching component function goals to overall goals; and team metacognition to detect and counter task‐disruptive developments. These processes appear to be complex multi‐person analogues of individual Incident Command processes identified previously. The findings have implications for issues such as: creating IMTs; training IMTs; managing IMTs; and providing decision support to IMTs. 相似文献