Search results for "Component"

showing 10 items of 1682 documents

Direct analysis in real-time high-resolution mass spectrometry as a valuable tool for polyphenols profiling in olive oil

2018

A fast and reliable method to characterize the polyphenolic compound profiles in extra virgin olive oil (EVOO) has been developed using direct analysis in real time (DART) and linear ion-trap Orbitrap mass spectrometry (LTQ-Orbitrap-MS). Hydroalcoholic extraction increased speed and reduced matrix effects, and DART-MS/MS ensured accurate analysis. Characterization of polyphenol fingerprinting in EVOO samples takes 2 min. This method exhibited proper linearity (R2 ≥ 0.99) in the range of 5–2500 μg g−1, limit of detection (LOD) of 1.5 μg g−1 (signal-to noise S/N = 3), and limits of quantitation (LOQs) of 5 μg g−1 (S/N = 10) for resveratrol (a polyphenol not detected in olive oil). Six spiked …

Detection limitDartChromatographyChemistryGeneral Chemical Engineering010401 analytical chemistryGeneral Engineering02 engineering and technology021001 nanoscience & nanotechnologyOrbitrapMass spectrometry01 natural sciencesDART ion source0104 chemical sciencesAnalytical Chemistrylaw.inventionlawPolyphenolPrincipal component analysis0210 nano-technologycomputerOlive oilcomputer.programming_language
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Epistemic Relativity: An Experimental Approach to Physics

2019

The recent concept of relativistic positioning system (RPS) has opened the possibility of making Relativity the general standard frame in which to state any physical problem, theoretical or experimental. Because the velocity of propagation of the information is finite, epistemic relativity proposes to integrate the physicist as a truly component of every physical problem, taking into account explicitly what information, when and where, the physicist is able to know. This leads naturally to the concept of relativistic stereometric system (RSS), allowing to measure the intrinsic properties of physical systems. Together, RPSs and RSSs complete the notion of laboratory in general relativity, al…

Development (topology)Theory of relativityGravitational fieldGeneral relativityComponent (UML)Physical systemCovariant transformationMeasure (mathematics)Epistemology
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5,12-Diselena-3,4,13,14-tetraazatricyclo[9.3.0.02,6]tetradeca-3,13-diene

2020

The title compound, C8H8N4Se2, crystallizes in a non-symmetrical conformation with a dihedral angle between the heterocycles of 45.0 (3)° and a nearly strain-free tetramethylene tether. The crystal studied was non-merohedrally twinned with a fractional contribution of 0.342 (3) for the minor twin component.

Dienebiology010405 organic chemistryChemistryComponent (thermodynamics)Crystal structureDihedral angle010402 general chemistrybiology.organism_classification01 natural sciences0104 chemical sciencesCrystalCrystallographychemistry.chemical_compoundTetraDeca-IUCrData
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Electron-deficient trifluoromethyl-substituted sub-components affect the properties of M4L4 tetrahedral cages

2017

Two supramolecular tetrahedral cages based on a new electron-deficient trifluoromethyl-substituted pyridylimine ligand are synthesised by sub-component self-assembly. Their structures are characterised by NMR und UV-Vis spectroscopy, high-resolution mass spectrometry and single crystal X-ray diffraction. The iron(II) complex shows host–guest chemistry, complex-to-complex transformations and novel electronic properties.

DiffractionTrifluoromethyl010405 organic chemistryLigandSupramolecular chemistry010402 general chemistryMass spectrometry01 natural sciences0104 chemical sciencesInorganic ChemistryCrystallographychemistry.chemical_compoundchemistryelectron-deficient trifluoromethyl-substituted sub-componentsTetrahedronSpectroscopyta116Single crystalDalton Transactions
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A model for managing and evaluating solar radiation for indoor thermal comfort

2007

Thermal comfort of people occupying indoor spaces depends, to a large extent, on the direct component of solar radiation incident on the human body. In turn, even the diffuse component of the solar radiation could affect the thermal sensations of people. Despite this evidence, at the present there is a lack in the availability of simple and reliable methods capable of taking into account the influence of the solar radiation on thermal balance in the human body. In this work a comprehensive method is presented for the computation of the mean radiant temperature of people in thermal moderate indoor environments in the presence of solar radiation. The effects produced on the amount of solar ra…

Direct componentRenewable Energy Sustainability and the EnvironmentThermalEvaluation methodsThermal comfortEnvironmental scienceGeneral Materials ScienceMean radiant temperatureRadiationThermal balanceAutomotive engineeringRemote sensing
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Symmetric units and group identities

1998

In this paper we study rings R with an involution whose symmetric units satisfy a group identity. An important example is given by FG, the group algebra of a group G over a field F; in fact FG has a natural involution induced by setting g?g −1 for all group elements g∈G. In case of group algebras if F is infinite, charF≠ 2 and G is a torsion group we give a characterization by proving the following: the symmetric units satisfy a group identity if and only if either the group of units satisfies a group identity (and a characterization is known in this case) or char F=p >0 and 1) FG satisfies a polynomial identity, 2) the p-elements of G form a (normal) subgroup P of G and G/P is a Hamiltonia…

Discrete mathematicsCombinatoricsSubgroupG-moduleMetabelian groupGeneral MathematicsQuaternion groupPerfect groupAlternating groupIdentity componentPermutation groupMathematicsmanuscripta mathematica
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Using Search Algorithms for Modeling Economic Processes

2013

Abstract Economic issues are placed in formal practice, when is desired a modelling of the economic process, a manufacturing process, a device, etc. Each share of that economic process is denoted by a, b, c, d, these actions with defined time periods and action pairs are formed strings of the form, ab * cab * bc ., ab, bb, bc. so for them there are no other restrictions. If the graph is viewed as a system image, nodes representing components, then an immediate interpretation of an arc (xi, xj) are the component xi that is said to directly influence component xj. If nodes have the significance of possible states of a system when a spring (xi.xj) means that, the system can jump from state xi …

Discrete mathematicsComputer scienceGeneral EngineeringEnergy Engineering and Power TechnologyState (functional analysis)Directed graphGraphInterpretation (model theory)AlgorithmSearch algorithmComponent (UML)Economic Process.System imageGraph (abstract data type)Operations managementFinite setModelProcedia Economics and Finance
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Witness computation for solving geometric constraint systems

2014

International audience; In geometric constraint solving, the constraints are represented with an equation system F(U, X) = 0, where X denotes the unknowns and U denotes a set of parameters. The target solution for X is noted XT. A witness is a couple (U_W, X_W) such that F(U_W, X_W) = 0. The witness is not the target solution, but they share the same combinatorial features, even when the witness and the target lie on two distinct connected components of the solution set of F(U, X) = 0. Thus a witness enables the qualitative study of the system: the detection of over- and under-constrained systems, the decomposition into irreducible subsystems, the computation of subsystems boundaries. This …

Discrete mathematicsConnected componentMathematical optimization[ INFO ] Computer Science [cs]Numerical algorithmsComputer scienceComputationNumerical analysisSystem FSolution setBinary constraint[INFO] Computer Science [cs]16. Peace & justiceGeometric constraint solvingWitnessSimplex algorithmWitness computation[INFO]Computer Science [cs]
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Topological invariants of stable immersions of oriented 3-manifolds in R4

2012

Abstract We show that the Z -module of first order local Vassiliev type invariants of stable immersions of oriented 3-manifolds into R 4 is generated by 3 topological invariants: The number of pairs of quadruple points and the positive and negative linking invariants l + and l − introduced by V. Goryunov (1997) [7] . We obtain the expression for the Euler characteristic of the immersed 3-manifold in terms of these invariants. We also prove that the total number of connected components of the triple points curve is a non-local Vassiliev type invariant.

Discrete mathematicsConnected componentPure mathematicsFirst order local Vassiliev type invariantsFirst ordersymbols.namesakeEuler characteristicsymbolsTopological invariantsGeometry and TopologyInvariant (mathematics)Stable immersionsSINGULARIDADESMathematicsTopology and its Applications
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A Generalization of Girod’s Bidirectional Decoding Method to Codes with a Finite Deciphering Delay

2012

In this paper we generalize an encoding method due to Girod (cf. [6]) using prefix codes, that allows a bidirectional decoding of the encoded messages. In particular we generalize it to any finite alphabet A, to any operation defined on A, to any code with finite deciphering delay and to any key x ∈ A+ , on a length depending on the deciphering delay. We moreover define, as in [4], a deterministic transducer for such generalized method. We prove that, fixed a code X ∈ A* with finite deciphering delay and a key x ∈ A *, the transducers associated to different operations are isomorphic as unlabelled graphs. We also prove that, for a fixed code X with finite deciphering delay, transducers asso…

Discrete mathematicsPrefix codeStrongly connected componentSettore INF/01 - InformaticaGeneralization020206 networking & telecommunications0102 computer and information sciences02 engineering and technology01 natural sciencesPrefix010201 computation theory & mathematicsEncoding (memory)0202 electrical engineering electronic engineering information engineeringCode (cryptography)AlphabetGirod's encoding codes finite deciphering delayDecoding methodsMathematics
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