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11.
The so-called covering algorithm for enclosing the solution set of parameter—dependent systems of nonlinear equations has been recently proposed by Neumaier (The Enclosure of Solutions of Parameter Dependent Systems of Equations, in: Moore, R. E. (ed.), Reliability in Computing: The Role of Interval Methods in Scientific Computations, Academic Press, 1988). However, in the covering algorithm, only one box is processed in each iteration. This paper presents a parallelized version of the covering algorithm, in which all boxes present are processed simultaneously in each iteration. It is shown through several examples that this strategy results in speed-up of the algorithm by several orders of magnitude, particularly so in demanding problems. The proposed parallelized version can be run even on ordinary computers, i.e., it does not require a parallel computer.  相似文献   
12.
Nickel doped cadmium sulfide (CdS:Ni2+) nanocrystals were synthesized at three different pH values. Nanocrystalline state of nickel doped cadmium sulfide material was established using X-ray diffraction analysis. Peak broadening and peak shifts in the XRD spectra were caused by the replacement of Cd2+ with Ni2+. Particles size (~62 nm) and the morphology of the synthesized nanoparticles were established through SEM analysis. The TEM analysis further established the presence of nanostate with particles size of 35 nm. The EDS analysis confirmed the existence of Ni in all the three samples. Blue shift in the absorption region and increase in the bandgap to the larger value (3.72 eV) were attributed to the nano dimensional state and incorporation of dopant into the host lattice. Weak metal sulfur interaction was identified from the FT-IR spectroscopy. The room temperature magnetic studies showed that 10% nickel doped CdS at 10 pH, 11.0 pH and 9.0 pH showed weak ferromagnetic and strong ferromagnetic hysteresis. The variations in the magnetic property of the nanomaterials were caused by the weak interaction of Ni2+ with the host material.  相似文献   
13.
We present our results on successful synthesis of pyrazine–MoO3 nanorod hybrids by using pyrazine and MoO3 nanorods. On the first stage, MoO3 nanorods were grown hydrothermally and, on the second stage, their mixture with pyrazine was again involved in a hydrothermal reaction to produce organic–inorganic hybrids. To understand the growth mechanism of the hybrids we varied time and temperature of the hydrothermal process. Intercalation of pyrazine was confirmed through X-ray diffraction analysis, X-ray photoelectron spectroscopy, X-ray emission spectroscopy, scanning electron microscopy methods. Upon calcinations, pyrazine was deintercalated, i.e. removed from the MoO3 hybrid system, and the MoO3 nanorods were found to bind together resulting in formation of MoO3 microslabs with increased surface area. Photodecomposition performance of the MoO3 nanorods, pyrazine–MoO3 hybrids and MoO3 microcrystals was studied against Procion Red MX-5B textile dye. A high photodecomposition performance was found to decrease when going from MoO3 nanorods to MoO3 microcrystal and, further, to pyrazine–MoO3 hybrids.  相似文献   
14.
Over the years, the attempts to elucidate the role of beneficial microorganisms in shaping human health are becoming fairly apparent. The functional impact conferred by such microbes is not only transmitted by viable cells or their metabolites but also through non-viable cells. Extensive research to unveil the protective action of such wonder bugs has resulted in categorizing the beneficial microflora and their bioactive metabolites into a variety of functional biotic concepts based on their intended applications in various forms. In the modern era, these are often termed as probiotics, prebiotics, synbiotics, postbiotics, next-generation probiotics, psychobiotics, oncobiotics, pharmabiotics, and metabiotics. Currently, the concept of traditional probiotics is being widened to include microbes beyond lactic acid bacteria. Indeed, this diversification has broadened the functional food portfolio from food to pharmaceuticals. In this context, the present review aims to summarize the existing biotic concepts and their differences thereof.  相似文献   
15.
The detected contrast and dynamic ranges of Cd1-xZnxTe semiconductor detectors have been measured, within the X-ray diagnostic energy range, using a contrast sensitivity phantom. The aim of this study is to optimize the image quality parameters of these solid state ionization devices for flat panel digital radiographic applications. The experimental results of this study indicate that Cd1-xZnxTe detectors have excellent detected contrast response and large dynamic range  相似文献   
16.
S.K. Nataraj 《Desalination》2009,249(1):12-17
Nanofiltration (NF) and reverse osmosis (RO) thin film composite polyamide membrane modules were used to remove the color from the contaminated solution mixture. The feasibility of membrane processes for treating simulated mixture by varying the feed pressures (100-400 psi) and feed concentrations was studied to assess the separation performance of both NF and RO membranes. It was found that the efficiency of NF and RO membranes used in the treatment of colored water effluents was greatly affected by the presence of salts and dyes in the mixture. Color removal by NF with a high rejection of 99.80% and total dissolved solids (TDS) of 99.99% was achieved from RO by retaining significant flux rate compared to pure water flux, which suggested that membranes were not affected by fouling during the simulated wastewater process operation. The effect of varying concentrations of Na2SO4 salt and methyl orange (MO) dye on the performance of spiral wound membranes was determined. Increasing the dye concentration from 500 to 1000 mg/L resulted in a decrease of salt rejection at all operating pressures and for both concentrations of 5000 and 10,000 mg/L as the feed TDS. Increasing the salt concentration from 5000 to 10,000 mg/L resulted in a slight decrease in dye removal.  相似文献   
17.
Allospecific CD8(+) T lymphocytes are an important component of the cellular response in allograft rejection. These cells recognize and engage MHC class I antigens, leading to allospecific cytolytic responses and graft rejection. In mouse kidney allografts that survive to 3 wk after transplantation, we noted that the majority of CD8(+) cells do not express surface alpha/beta T cell receptor alpha/beta(TCR), gamma/deltaTCR, or CD3. However, these CD8(+)TCR- cells did express surface markers characteristic of T cells, including Thy1.2, CD2, and CD5. In addition, the CD8(+)TCR- cells expressed mRNA for TCR Vbeta gene families, and nearly half stained positive for cytoplasmic Vbeta8 protein, suggesting that they are T cells that have downregulated alpha/betaTCR protein expression from their cell surfaces. When these surface TCR- cells were isolated from kidney allografts by flow cytometry and cultured in the presence of either allogeneic or syngeneic stimulators, nearly 100% of cells reacquired normal levels of alpha/betaTCR expression with disproportionate usage of Vbeta8 chains. After recovery of their surface TCR expression, the CD8(+)TCR- population demonstrated strong alloreactivity in culture. These results suggest that the substantial number of CD8(+)TCR- cells found in long-term surviving mouse kidney allografts are alpha/beta-T cells that have downregulated their cell surface expression of TCR. While in other systems this phenotype may identify cells that have engaged antigen, our results indicate that loss of TCR expression by CD8(+) kidney graft-infiltrating cells may not depend on antigen engagement and that elements in the microenvironment of the kidney graft play a key role in this process. Factors that modulate expression of TCR by graft-infiltrating lymphocytes may have an important role in regulating rejection responses.  相似文献   
18.
19.
In this paper,an improved algorithm is proposed for unconstrained global optimization to tackle non-convex nonlinear multivariate polynomial programming problems.The proposed algorithm is based on the Bernstein polynomial approach.Novel features of the proposed algorithm are that it uses a new rule for the selection of the subdivision point,modified rules for the selection of the subdivision direction,and a new acceleration device to avoid some unnecessary subdivisions.The performance of the proposed algorithm is numerically tested on a collection of 16 test problems.The results of the tests show the proposed algorithm to be superior to the existing Bernstein algorithm in terms of the chosen performance metrics.  相似文献   
20.
Accumulative roll bonding of two aluminium alloys, AA2219 and AA5086 was carried out up to 8 passes. During the course of ARB, the deformation inhomogeneity between the two alloy layers results in interfacial instability after the 4th pass, necking of the AA5086 layers after the 6th pass and fracture along the necked regions after the 7th and 8th pass. The EBSD analysis shows deformation bands along the interfaces after 8 passes of ARB. The ARB-processed materials predominantly show characteristic deformation texture components. The weak texture after the 2nd pass results from the combination of a weakly-textured starting AA2219 layer and a strongly-textured starting AA5086 layer. A strong deformation texture forms due to the high imposed strain after a higher number of ARB passes. Subgrain formation and related shear banding induces copper/S components in the case of the small elongated grains, while planar slip leads to the formation of brass component in the large elongated grains.  相似文献   
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