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51.

We theoretically analyze the detection of a cancer cell in the one-dimensional photonic crystal by infiltrating different sample cells in the cavity layer. The defect modes appear in their transmission spectra only if the nanocomposite layers are included on either side of the cavity layer. This analysis is carried out by a dielectric constant and the transmittance peak of the cancer cell is compared with the normal cell. The transmittance peak shifts are analyzed with various filling factors for optimization purposes. Through the shifting spectrum, the sensitivity of cancer cell from the normal cell is obtained from a minimum of 42 nm/RIU to a maximum of 43 nm/RIU.

  相似文献   
52.
Literally, the word compliance suggests conformity in fulfilling official requirements. This paper presents the results of the analysis and design of a class of protocols called compliant cryptologic protocols (CCPs). The paper presents a notion for compliance in cryptosystems that is conducive as a cryptologic goal. CCPs are employed in security systems used by at least two mutually mistrusting sets of entities. The individuals in the sets of entities only trust the design of the security system and any trusted third party the security system may include. Such a security system can be thought of as a broker between the mistrusting sets of entities. Published online: 15 November 2002  相似文献   
53.
Virtualized datacenters and clouds are being increasingly considered for traditional High-Performance Computing (HPC) workloads that have typically targeted Grids and conventional HPC platforms. However, maximizing energy efficiency and utilization of datacenter resources, and minimizing undesired thermal behavior while ensuring application performance and other Quality of Service (QoS) guarantees for HPC applications requires careful consideration of important and extremely challenging tradeoffs. Virtual Machine (VM) migration is one of the most common techniques used to alleviate thermal anomalies (i.e., hotspots) in cloud datacenter servers as it reduces load and, hence, the server utilization. In this article, the benefits of using other techniques such as voltage scaling and pinning (traditionally used for reducing energy consumption) for thermal management over VM migrations are studied in detail. As no single technique is the most efficient to meet temperature/performance optimization goals in all situations, an autonomic approach that performs energy-efficient thermal management while ensuring the QoS delivered to the users is proposed. To address the problem of VM allocation that arises during VM migrations, an innovative application-centric energy-aware strategy for Virtual Machine (VM) allocation is proposed. The proposed strategy ensures high resource utilization and energy efficiency through VM consolidation while satisfying application QoS by exploiting knowledge obtained through application profiling along multiple dimensions (CPU, memory, and network bandwidth utilization). To support our arguments, we present the results obtained from an experimental evaluation on real hardware using HPC workloads under different scenarios.  相似文献   
54.
X-ray photoelectron spectroscopic studies on the activated pure CaNi5 alloy as well as the hydride formed at 1 atm pressure and room temperature, CaNi5H4.8, showed that on activation calcium segregates to the surface and forms the oxide, whereas most of the nickel on the surface is present in the metallic form. This indicates that the coexistance of the oxide phase and the metal phase is essential for the facile hydriding behaviour of CaNi5.  相似文献   
55.
The available data on the effect of neutron and α-particle irradiation on the superconducting properties and the low-temperature specific heat capacity of single- and polycrystalline V3Si were analyzed in a unified manner. It was found that the electron-phonon renormalization parameter λ does not vary simply proportionally to the bare density of electron states at the Fermi level as had been earlier conjectured by Dynes and Varma, nor does it vary in exactly the same manner as found by Fradin and Williamson to hold for a variety of vanadium-based A15 structure compounds and pseudobinary alloys. When the behavior of V3Si is compared with that of Nb3Sn, Nb3Al, and Nb3Ge, it is seen that the response to disorder of parameters of importance in the superconductivity of these compounds does not follow any simple, universal behavior.  相似文献   
56.
We have investigated the preventive effects of squalene against isoprenaline-induced myocardial infarction in male albino rats. Supplementation with squalene significantly prevented the isoprenaline-induced adverse changes in the levels of protein and glycoprotein components in plasma and heart tissue of experimental groups of rats. It exerted an antioxidant effect by inhibiting the isoprenaline-induced lipid peroxidation and by maintaining the level of non-enzymatic free radical-scavenger, reduced glutathione at near normalcy. Histopathological observations also confirmed the possible cardioprotective action of squalene by maintaining the normal architecture of the heart tissue. The results of the present investigation demonstrate that supplementation with squalene offers cardioprotection in experimental rats by its antioxidant and membrane- stabilizing properties.  相似文献   
57.
Heavy metals are an important group of chemical contaminants and food is the major vehicle for entry into the system. Fish constitute a major source of heavy metals in food. Concentration of heavy metals in commercially important species of fish, shellfish and fish products from fish markets in and around the Cochin area was evaluated using an atomic absorption spectrometer. The concentration ranges of Cd, Pb, Hg, Cr, As, Zn, Cu, Co, Mn, Ni, and Se in the samples were <0.07–1, <0.07–1.32, <0.05–2.31, <0.05 to 3.65, <0.1–4.14, 0.6 to 165, 0.15 to 24, <0.02 to 0.85, <0.08 to 9.2, <0.032–1.38 and; <0.03–1.35 mg/kg, respectively. The present study showed that different metals were present in the samples at different levels but within the maximum residual levels prescribed by the EU and USFDA and the fish and shellfish from these areas, in general, are safe for human consumption.  相似文献   
58.
Knowledge of the effective thermal diffusivity changes of systems undergoing reactions where heat transfer plays an important role in the reaction kinetics is essential for process understanding and control. Carbothermic reduction process of magnetite containing composites is a typical example of such systems. The reduction process in this case is highly endothermic and hence, the overall rate of the reaction is greatly influenced by the heat transfer through composite compact. Using Laser-Flash method, the change of effective thermal diffusivity of magnetite-graphite composite pellet was monitored in the dynamic mode over a pre-defined thermal cycle (heating at the rate of 7 K/min to 1423 K (1150 °C), holding the sample for 270 minutes at this temperature and then cooling it down to the room temperature at the same rate as heating). These measurements were supplemented by Thermogravimetric Analysis under comparable experimental conditions as well as quenching tests of the samples in order to combine the impact of various factors such as sample dilatations and changes in apparent density on the progress of the reaction. The present results show that monitoring thermal diffusivity changes during the course of reduction would be a very useful tool in a total understanding of the underlying physicochemical phenomena. At the end, effort is made to estimate the apparent thermal conductivity values based on the measured thermal diffusivity and dilatations.  相似文献   
59.
A modification of the DLTS (Deep Level Transient Spectroscopy) technique for interface-state measurement is described in which the surface potential is used to determine the energy of the interface states contributing to the emission signal. This technique allows an accurate and unambiguous determination of interface-state energies and cross sections. Expressions are determined for interface-state emission as a function of surface potential. Measurements of interface-state density and majority-carrier cross sections as functions of energy for n- and p-type MOS samples are presented.  相似文献   
60.
A program to study the effect of Sb, P, Sn and B on creep properties of four normalized and tempered 1.25 Cr-0.5 Mo steels at 538°C (1000°F) has been completed. Results show that even a combined addition of large amounts of Sb, P and Sn does not affect short time creep strength or ductility of the steel at 538°C (1000°F). Addition of B resulted in an increase or decrease of creep strength depending on the nature of the impurity species present, presumably due to B-impurity interactions. Regardless of the effect on creep strength, B additions caused sharp reductions in rupture ductility in all cases. Comparison of the present results on the four laboratory steels (100 pct bainite) with results of a previous study on a commercial steel (60 pct bainite + 40 pct ferrite) show that the effect of microstructure becomes negligible and rupture strength values of the various steels at 538°C (1000°F) approach each other at rupture times in excess of 104 h.  相似文献   
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