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881.
882.
V. P. Beskachko O. A. Golovnya A. E. Korenchenko 《Journal of Engineering Physics and Thermophysics》2007,80(1):132-135
The results of a numerical solution of the problem of vibrations of a torsion viscosimeter filled with an incompressible viscoplastic
liquid are presented. It has been shown that in the vicinity of the rotation axis there appears a dead zone, whose boundary
changes in the process of vibrations. The influence of plastic properties of the liquid on the characteristics of viscosimeter
vibrations has been determined. A method for identifying viscoplastic properties by the observed parameters of vibrations
is proposed.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 1, pp. 124–127, January–February, 2007. 相似文献
883.
884.
885.
On 25 June 2003, a new mass-mailing worm, Sobig.E, emerged. The worm was highly successful at infecting computer systems. It is the fifth revision of a worm that first raised its ugly head in January 2003. There is strong evidence that spammers use infected computers to relay unsolicited commercial e-mail. 相似文献
886.
J. R. Díaz-Estrada E. Camps L. Escobar-Alarcón J. A. Ascencio 《Journal of Materials Science》2007,42(4):1360-1368
Deposition of Ti was carried out by laser ablation onto hydroxyapatite porous discs in an Ar atmosphere. Ti nanoparticles
were deposited onto HAp surface in order to modify its roughness and morphology as it is observed by scanning electron microscopy
(SEM) and scanning probe microscopy (SPM). A homogeneous distribution of Ti over the disc surface was corroborated by elemental
mapping. A comparison of the hydroxyapatite hardness before and after deposition was performed using SPM nanoindentation.
Transmission Electron Microscopy (TEM) showed that the Ti nanoparticles obtained were covered by an oxygen shell. It is shown
that surface modifications of the covered HAp by Ti result in better mechanical properties, reducing the possible damage to
the HAp ceramic by friction or impacts as it often happens in meniscus, bone junctions and the inclusion of prosthesis for
human treatments. 相似文献
887.
888.
Dario Pasini Luigi Garlaschelli Elza Bontempi Laura E. Depero 《Fullerenes, Nanotubes and Carbon Nanostructures》2007,15(5):367-378
The synthesis of a series of polymers and cyclopolymers bearing crown ethers of differing structure and affinities towards primary ammonium ions is discussed. These polymers have been tested in their efficiency to form structurally homogeneous thin films when blended with an amphiphilic C60 compound containing a primary ammonium ion functional group. The X-ray reflectivity characterization of the films revealed that the polymer bearing the crown ether with the least affinity for primary ammonium ions, but having the highest degree of polymerization, is the most effective in forming structurally homogeneous thin films. 相似文献
889.
P. A. Borodovskii A. F. Buldygin A. S. Tokarev E. V. Chernyavskii 《Russian Microelectronics》2005,34(5):316-324
A further investigation is conducted into a new microwave method for evaluating bulk lifetime in silicon ingots 相似文献
890.
In this paper we consider two performance modelling techniques from the perspectives of model construction, generation of
an underlying continuous time Markov process, and the potential for reduction in the Markov process. Such careful comparison
of modelling techniques allows us to appreciate the strengths and weaknesses of different approaches, and facilitates cross-fertilization
between them. In the present case we take a characteristic of one formalism, functional rates in Stochastic Automata Networks,
and introduce it to the other formalism, Performance Evaluation Process Algebra. We investigate the benefits of this cross-fertilization,
particularly from the perspectives of Markov process generation and reduction. 相似文献