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Required Properties (required + property)
Selected AbstractsPhase ,: Tracking Down Material DefectsIMAGING & MICROSCOPY (ELECTRONIC), Issue 2 2009Wanted: Steel to Handle Extreme Demands of Petroleum Extraction The quest for extraction of petroleum and natural gas requires superior competence from both humans and materials involved. The demands made on both go far beyond normal conditions. The materials used must be produced using the best raw materials and produced at premium quality levels. Then even the tiniest fluctuations in the composition of the steel used for drills, drill rods and their casing can influence and decisively alter their required properties , such as degree of hardness, ductility and malleability. [source] A review of reliable numerical models for three-dimensional linear parabolic problemsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 1 2007I. Faragó Abstract The preservation of characteristic qualitative properties of different phenomena is a more and more important requirement in the construction of reliable numerical models. For phenomena that can be mathematically described by linear partial differential equations of parabolic type (such as the heat conduction, the diffusion, the pricing of options, etc.), the most important qualitative properties are: the maximum,minimum principle, the non-negativity preservation and the maximum norm contractivity. In this paper, we analyse the discrete analogues of the above properties for finite difference and finite element models, and we give a systematic overview of conditions that guarantee the required properties a priori. We have chosen the heat conduction process to illustrate the main concepts, but engineers and scientists involved in scientific computing can easily reformulate the results for other problems too. Copyright © 2006 John Wiley & Sons, Ltd. [source] Fuzzy adjunctions and fuzzy morphological operations based on implicationsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 12 2009Y. Shi The concept of adjunction plays an important role in mathematical morphology. If the morphological operations, dilation and erosion form an adjunction in a complete lattice, then they, as well as the closing and opening constructed by them, will fulfill certain required properties in an algebraic context. In the context of fuzzy mathematical morphology, which is an extension of binary morphology to gray-scale morphology based on fuzzy set theory, we use conjunctions and implications to define fuzzy dilations and fuzzy erosions. In this paper, we investigate when these pairs of dilations and erosions form a fuzzy adjunction, which is also defined by an implication. We find that the so-called adjointness between a conjunction and an implication plays an important role here. Finally, we develop a theorem stating that a conjunction that is adjoint with an implication cannot only be generated by an R-implication but also by other implications. This allows the easy construction of fuzzy adjunctions. © 2009 Wiley Periodicals, Inc. [source] Radiosynthesis and in vivo evaluation of [11C]Ro-647312: a novel NR1/2B subtype selective NMDA receptor radioligandJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 13 2004Frédéric Dollé Abstract [2-(3,4-Dihydro-1H-isoquinolin-2-yl)-pyridin-4-yl]-dimethylamine, Ro-647312 (1) represents a new novel class of NR1/2B subtype selective NMDA ligand. Ro-647312 has been radiolabelled with carbon-11 using [11C]methyl triflate from the nor- methyl compound 2. The reaction was performed in acetone as solvent using aqueous NaOH as base. Following HPLC purification [11C]Ro-647312 ([11C]- 1) was obtained in 6.9,9.2% (n = 3) radiochemical yield decay-corrected based on starting [11C]CO2, with specific radioactivity measured at the end of the radiosynthesis ranging from 1.0 to 3.5 Ci/µmol (37,129 GBq/µmol). Radiochemical and chemical purities were assessed as >99 and >95%, respectively. Following i.v. injection of [11C]- 1 in rat, the distribution of radioactivity was homogeneous in all brain structures and did not correlate with the known distribution of NR2B subunits. The radioactivity observed in plasma was also higher than any brain structure throughout the time course of the experiment. [11C]- 1 does not possess the required properties for imaging NMDA receptors using positron emission tomography. Copyright © 2004 John Wiley & Sons, Ltd. [source] Optoelectronic properties of transparent p-type semiconductor CuxS thin filmsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 7 2010P. Parreira Abstract Nowadays, among the available transparent semiconductors for device use, the great majority (if not all) have n-type conductivity. The fabrication of a transparent p-type semiconductor with good optoelectronic properties (comparable to those of n-type: InOx, ITO, ZnOx or FTO) would significantly broaden the application field of thin films. However, until now no material has yet presented all the required properties. Cu2S is a p-type narrow-band-gap material with an average optical transmittance of about 60% in the visible range for 50,nm thick films. However, due to its high conductivity at room temperature, 10,nm in thickness seems to be appropriate for device use. Cu2S thin films with 10,nm in thickness have an optical visible transmittance of about 85% rendering them as very good candidates for transparent p-type semiconductors. In this work CuxS thin films were deposited on alkali-free (AF) glass by thermal evaporation. The objective was not only the determination of its optoelectronic properties but also the feasibility of an active layer in a p-type thin film transistor. In our CuxS thin films, p-type high conductivity with a total visible transmittance of about 50% have been achieved. [source] Thin-film silicon solar cell technologyPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 2-3 2004A. V. Shah Abstract This paper describes the use, within p,i,n - and n,i,p -type solar cells, of hydrogenated amorphous silicon (a-Si:H) and hydrogenated microcrystalline silicon (,c-Si:H) thin films (layers), both deposited at low temperatures (200°C) by plasma-assisted chemical vapour deposition (PECVD), from a mixture of silane and hydrogen. Optical and electrical properties of the i -layers are described. These properties are linked to the microstructure and hence to the i -layer deposition rate, that in turn, affects throughput in production. The importance of contact and reflection layers in achieving low electrical and optical losses is explained, particularly for the superstrate case. Especially the required properties for the transparent conductive oxide (TCO) need to be well balanced in order to provide, at the same time, for high electrical conductivity (preferably by high electron mobility), low optical absorption and surface texture (for low optical losses and pronounced light trapping). Single-junction amorphous and microcrystalline p,i,n -type solar cells, as fabricated so far, are compared in their key parameters (Jsc, FF, Voc) with the [theoretical] limiting values. Tandem and multijunction cells are introduced; the ,c-Si: H/a-Si: H or [micromorph] tandem solar cell concept is explained in detail, and recent results obtained here are listed and commented. Factors governing the mass-production of thin-film silicon modules are determined both by inherent technical reasons, described in detail, and by economic considerations. The cumulative effect of these factors results in distinct efficiency reductions from values of record laboratory cells to statistical averages of production modules. Finally, applications of thin-film silicon PV modules, especially in building-integrated PV (BIPV) are shown. In this context, the energy yields of thin-film silicon modules emerge as a valuable gauge for module performance, and compare very favourably with those of other PV technologies. Copyright © 2004 John Wiley & Sons, Ltd. [source] An amino acid "transmembrane tendency" scale that approaches the theoretical limit to accuracy for prediction of transmembrane helices: Relationship to biological hydrophobicityPROTEIN SCIENCE, Issue 8 2006Gang Zhao Abstract Hydrophobicity analyses applied to databases of soluble and transmembrane (TM) proteins of known structure were used to resolve total genomic hydrophobicity profiles into (helical) TM sequences and mainly "subhydrophobic" soluble components. This information was used to define a refined "hydrophobicity"-type TM sequence prediction scale that should approach the theoretical limit of accuracy. The refinement procedure involved adjusting scale values to eliminate differences between the average amino acid composition of populations TM and soluble sequences of equal hydrophobicity, a required property of a scale having maximum accuracy. Application of this procedure to different hydrophobicity scales caused them to collapse to essentially a single TM tendency scale. As expected, when different scales were compared, the TM tendency scale was the most accurate at predicting TM sequences. It was especially highly correlated (r = 0.95) to the biological hydrophobicity scale, derived experimentally from the percent TM conformation formed by artificial sequences passing though the translocon. It was also found that resolution of total genomic sequence data into TM and soluble components could be used to define the percent probability that a sequence with a specific hydrophobicity value forms a TM segment. Application of the TM tendency scale to whole genomic data revealed an overlap of TM and soluble sequences in the "semihydrophobic" range. This raises the possibility that a significant number of proteins have sequences that can switch between TM and non-TM states. Such proteins may exist in moonlighting forms having properties very different from those of the predominant conformation. [source] | |||||||||||||