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991.
E. S. Gorkunov S. Yu. Mitropol’skaya A. M. Povolotskaya 《Russian Journal of Nondestructive Testing》2005,41(3):175-181
Stacks of steel plates having different values of magnetic hardness and separated with nonferromagnetic gaps are investigated. The coercive force and the residual magnetic induction of a stack measured in a closed magnetic circuit depend on the layout of the plates in the stack and on the thickness of nonmagnetic gaps between them.__________Translated from Defektoskopiya, Vol. 41, No. 3, 2005, pp. 55–62.Original Russian Text Copyright © 2005 by Gorkunov, Mitropol’skaya, Povolotskaya.Dedicated to the Anniversary of the 100th Birthday of Corresponding Member of the Russian Academy of Sciences M. N. Mikheev 相似文献
992.
大庆油田萨中开发区北一二排西部上返二类油层聚合物驱区块为一套陆相河流-三角洲碎屑岩沉积,由于二类油层渗透率、孔喉半径、有效厚度分布相对于主力油层均匀,适宜采用分子量分布宽度指数较大的中分子量聚合物驱油,可提高聚合物驱油效果。经室内岩心模拟实验,采用分子量分布宽度指数为23的中分子量聚合物进行二类油层聚合物驱油,相对普通中分子量聚合物可以多提高采收率1.2个百分点。 相似文献
993.
The safe operation of VVéR reactors has been discussed throughout the entire design process, taking account of the normative
documentation, including the international requirements (IAEA, EUR). After the first domestic normative document “Basic principles
for securing the safety of nuclear power plants” was approved in 1973, work began on the reconstruction of the first-generation
VVéR-440 power-generating units. The measures taken to increase safety concerned all types of reactors VVéR-440 and-1000.
Information on implementing these measures is presented.
__________
Translated from Atomnaya énergiya, Vol. 101, No. 2, pp. 87–93, August, 2006. 相似文献
994.
V. P. Vasilevskii M. N. Mikhailov A. A. Petrov M. I. Rozhdestvenskii Yu. M. Cherkashov 《Atomic Energy》2006,100(4):295-301
The basic stages and directions of upgrading and reconstruction of the power-generating units of nuclear power plants with
RBMK reactors over a period of 20 yr since the Chernobyl accident are reflected in this paper. The greatest amount of work
was done in 1986–1990 on all units with RBMK-1000 and-1500 reactors which were operating at that time in the USSR. The purpose
of the upgrade was to improve the neutron-physical characteristics of the reactor cores, increase the response speed of the
safety and control system and decrease the positive effect of water outflow from the cooling loop of this system, increase
the flow capacity of the systems performing emergency discharge of the steam-gas mixture from the reactor, and improve the
basic operating documentation.
The subsequent stages of the upgrading and reconstruction concerned mainly the first-generation power-generating units (Nos.
1 and 2 units of the Leningrad and Kursk nuclear power plants). These works were performed to make the power-generating units
conform to the requirements of the modern normative documents on safety and allow for the possibility of these units to remain
in operation after the nominal 30-yr service life has been exhausted.
__________
Translated from Atomnaya énergiya, Vol. 100, No. 4, pp. 312–320, April, 2006. 相似文献
995.
基于CAN总线的汽车测试解决方案 总被引:1,自引:0,他引:1
更高功能的汽车设计带动更复杂的汽车电子测试技术的发展。中国的汽车测试界尤其面对着设备的短缺、技术的匮乏等诸多困难。本文针对中国的汽车电子测试业。介绍了一种集成的软硬件同步平台。它基于CAN总线领域中的PXI总线。及国际广泛应用的测试管理TestStand软件。构建成高集成度、可靠性、升级维护方便、开放彻底的测试系统。 相似文献
996.
In this paper, we present design features, implementation, and validation of a satellite simulator subsystem for the Korea Multi‐Purpose Satellite‐2 (KOMPSAT‐2). The satellite simulator subsystem is implemented on a personal computer to minimize costs and trouble on embedding onboard flight software into the simulator. An object‐oriented design methodology is employed to maximize software reusability. Also, instead of a high‐cost commercial database, XML is used for the manipulation of spacecraft characteristics data, telecommand, telemetry, and simulation data. The KOMPSAT‐2 satellite simulator subsystem is validated by various simulations for autonomous onboard launch and early orbit phase operations, anomaly operation, and science fine mode operation. It is also officially verified by successfully passing various tests such as the satellite simulator subsystem test, mission control element system integration test, interface test, site installation test, and acceptance test. 相似文献
997.
Christina Dirk‐Faitakis D Grant Allen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(7):737-745
This paper describes the development and simulation of an unsteady state biofilter model used to predict dynamic behaviour of cyclically‐operated biofilters and compares it with experimental results obtained from three, parallel, bench‐scale biofilters treating both periodically fluctuating concentrations and constant concentrations of an α‐pinene‐laden gas stream. The dynamic model, using kinetic parameters estimated from the constant concentration biofilter, was able to predict the performance of cyclic biofilters operating at short cycle periods (ie, in the order of minutes and hours). Steady state kinetic data from a constant concentration biofilter can be used to predict unsteady state biofilter operation. At a 24 h cycle period, the dynamic model compared well with experimental results. For long cycle periods (ie, hours and days), removal efficiency decreased after periods of non‐loading: the longer the period of non‐loading, the poorer the biofilter's performance at the re‐commencement of pollutant loading. At longer time scales the model did not effectively predict transient behaviour, as adsorption and changes in kinetic parameters were not accounted for. Modelling results showed that similar biofiltration performance for the cyclic and constant concentration biofiltration of α‐pinene is expected for biofilters operating solely in the first order kinetics regime. Poorer performance for cyclic biofilters following Monod kinetics spanning the entire kinetics range is expected as the cycle amplitude increases. The most important parameters affecting the performance of a cyclically‐operated biofilter with short cycle periods are: amplitude of cyclic fluctuations, Cg, max/Cg, relative value of the half‐saturation constant in the Monod expression, Ks, and effective diffusivity of α‐pinene in the biofilm, De. Copyright © 2005 Society of Chemical Industry 相似文献
998.
RM Martín‐Aranda E Ortega‐Cantero ML Rojas‐Cervantes MA Vicente‐Rodríguez MA Baares‐Muoz 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(2):234-238
α,β‐Unsaturated nitriles have been synthesized by Knoevenagel condensation of a carbonylic compound with malononitrile, assisted by sonochemical irradiation. Two alkaline‐promoted clays (Li+‐ and Cs+‐exchanged saponites) have been employed as catalysts. The influence of the carbonylic compound (benzaldehyde or cyclohexanone) and the use of a solvent on the catalytic activity have been studied. Remarkable increase in the conversion values has been found when the reaction is activated by ultrasound, as compared with the thermal activation. In this green, solvent‐free procedure, α,β‐unsaturated nitriles have been produced in very high yields (97%) when the Cs+‐saponite is used as catalyst. Copyright © 2004 Society of Chemical Industry 相似文献
999.
The Bloch mode propagation through the chirped periodical structure is defined by its local dispersion relation. In a slowly varying structure its time delay is the integral of the local inverse group velocity along the propagation direction. The integration can be strongly simplified for linearly chirped structures if the assumption is made that the local dispersion relation is just a scaled and shifted version of the dispersion relation at the input. This assumption leads to exact solutions for the structures with locally uniaxial deformation and provides a good approximation for arbitrary structures with small chirps. The approach is demonstrated for high index contrast chirped Bragg mirrors and complicated photonic crystal waveguide structures, including coupled waveguides and a slow group velocity waveguide. 相似文献
1000.
The formation specifics of the structure and phase composition of densely sintered ceramics based on a low-melting argillaceous
material from Belarus together with a combined flux and a grog additive are investigated. The correlation between the physicochemical
properties, structure, phase composition, and the time-temperature firing schedules of the developed materials are investigated.
Electron probe microanalysis makes it possible to monitor variations in the chemical composition at various local sites and
compare it with the estimated composition of the mixture. The optimum regimes for the heat treatment of articles are determined.
__________
Translated from Steklo i Keramika, No. 6, pp. 32 – 36, June, 2005. 相似文献