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64.
V. Angayarkanni B. Palanivel S. Natarajan M. Rajagopalan 《Journal of Low Temperature Physics》1992,86(3-4):165-176
We report here a theoretical calculation of band strucure and superconductivity in the fcc phase of lanthanum under pressure. The effect of pressure on the band structure is obtained by means of the linear muffintin orbital method. McMillan's formula is used to calculate the superconducting transition temperature (T
c). It is found that the value ofT
c increases continuously up to 17.8 GPa and then begins to decrease. The change in the slope ofT
c is attributed to the appearance of a new piece of Fermi surface. The calculated values ofT
c are compared with the available experimental data. 相似文献
65.
The issues involved in building dynamic, hard real-time systems, in which resource availability and requirements are not fixed, are discussed. It is shown that the problem of ensuring timing correctness in dynamic real-time systems has three aspects: resource requirements, resource availability, and guarantees. These issues overlap, and a single mechanism or technique may address several issues. The R-Shell, an object-oriented framework that structures resources in a class hierarchy so that they can be selected or substituted dynamically is described 相似文献
66.
A bioprocessing approach for the extraction of base, nuclear and precious metals from refractory and lean grade ores has been
reviewed in this paper. Characteristic morphological features ofThiobacillus ferrooxidans, the organism which has been extensively used for biooxidation of sulphide ores have been discussed. Mechanisms of chemoautotrophy
and mineral oxidation have been illustrated. The current engineering applications of this microorganism have also been brought
out. Various methods for accelerating the growth ofThiobacillus ferrooxidans for faster biooxidation and genetic manipulation for development of desired strains have been outlined. 相似文献
67.
R Solberg M Sandberg V Natarajan PA Torjesen V Hansson T Jahnsen K Taskén 《Canadian Metallurgical Quarterly》1997,138(1):169-181
68.
Telomerase is a ribonucleoprotein whose activity has been detected in germline cells and in neoplastic and immortal cells. Telomerase compensates the telomere loss arising by the end replication problem by synthesizing telomeric repeats at the 3' end of the eukaryotic chromosomes. Telomerase is reactivated during cancer progression in human and mice. In order to determine whether the telomerase activity can be upregulated in vitro in response to DNA damaging agents, we examined the telomerase activity in five Chinese hamster cell lines following exposure to 5 J/m2 or 40 J/m2 UV-C radiation. All the cell lines tested showed an increase in telomerase activity in the PCR-based telomeric repeat amplification protocol (TRAP) in a dose dependent manner. This increase in telomerase activity correlated well with the number of cells being in the S and G2/M phase after UV exposure. However, in unirradiated control cells, similar levels of telomerase activity were observed in different phases of the cell cycle. Furthermore, telomeric signals were clustered in one or more parts of the disintegrating nuclear particles of the apoptotic cell as detected by fluorescence in situ hybridization (FISH). This is the first study to demonstrate the induction of telomerase activity following exposure to DNA-damaging agents like UV radiation in Chinese hamster cells in vitro. 相似文献
69.
This article discusses immunization, development, vision, blood pressure, dentition, behavioral, and environmental screening for preschool children. The authors then discuss screening for children in the early school years. Injury and violence prevention and topics of sexuality for the preadolescent are also presented. 相似文献
70.
Electric vehicles (EVs) are becoming increasingly popular because of their low operating costs. However, the anticipated increase in EV usage presents opportunities as well as challenges for utilities. This paper models EV charging behavior of active consumers who strategize their EV charging schedule to minimize the charging cost. The electric utility employs a temporal and spatially varying real-time pricing scheme that minimizes peak-to-average load ratio by influencing charging behavior of multiple active consumers. These active consumers decide their optimal charging strategy based on real-time electricity prices in order to minimize their EV charging cost. A model predictive control (MPC)-based optimal pricing scheme for electric utility and optimal charging strategy for active consumers is proposed. Effects of the proposed approach on load profile is verified using simulations. 相似文献