Search results for "Meter"

showing 10 items of 16915 documents

Sound conversion phenomena at the free surface of liquid helium. I. Calculation of the coefficients of reflection, transmission, and transformation o…

1980

On the basis of a set of boundary conditions describing quite generally mass and energy transport processes across the free surface of helium II, the acoustic coefficients of reflection, transmission, and transformation of first sound, second sound, and the sound wave propagating in the vapor are calculated in the case of perpendicular incidence of sound waves against the liquid-vapor phase boundary. Considering rigorously the influences of the Onsager surface coefficients, the isobaric thermal expansion coefficients, and the thermal conductivities of the liquid and the vapor, we derive sets of equations from which the acoustic coefficients are determined numerically. For estimations, simpl…

Absorption (acoustics)Materials scienceAcoustic interferometerMechanicsAcoustic waveAcoustic source localizationCondensed Matter PhysicsAtomic and Molecular Physics and OpticsComputer Science::SoundFree surfaceSecond soundReflection (physics)General Materials ScienceAtomic physicsSound speed gradientJournal of Low Temperature Physics
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Lanthanide–saccharide chemistry: synthesis and characterisation of Ce(III)–saccharide complexes

2000

A series of nine Ce(III) complexes has been synthesised with seven different monosaccharides (D-glucose, D-fructose, D-galactose, D-mannose, L-sorbose, D-ribose and D-xylose) and two different disaccharides (D-maltose and L-lactose), and these have been characterised with various analytical, spectral, magnetic and electrochemical techniques. The NMR studies have highlighted some interesting features about the metal-ion-binding pattern of the saccharides. Some additional coordination has been proposed along with the chelating groups in the saccharide molecules, based on the shifts in 13C NMR spectra. On the other hand, solution absorption studies and solid-state magnetic susceptibilities hav…

Absorption SpectraLanthanideMagnetic Resonance SpectroscopyStereochemistryMetal ions in aqueous solutionMannoseDisaccharidesBiochemistryAnalytical Chemistrychemistry.chemical_compoundSpectroscopy Fourier Transform InfraredElectrochemistryMonosaccharideOrganic chemistryMoleculeChelating Agentschemistry.chemical_classificationMolecular StructureSpectrometersCircular DichroismMetal IonsMonosaccharidesOrganic ChemistryElectric ConductivityElectron Spin Resonance SpectroscopyFructoseCeriumGeneral MedicineCarbon-13 NMRSorbosechemistrySpectrophotometryMetals Rare EarthElectrochemical AnalysisCarbohydrate Research
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Line intensities of CH3D in the Triad region: 6–10μm

2004

Abstract Line intensities of the three lowest fundamentals of the 12CH3D Triad are modeled with an RMS of 3.2% using over 2100 observed values retrieved by multispectrum fitting of enriched sample spectra recorded with two Fourier transform spectrometers. The band strengths of the Triad in units of 10−18 cm−1/(molecule cm−2) at 296 K are, respectively, 2.33 for ν6 (E) at 1161 cm−1, 1.75 for ν3 (A1) at 1307 cm−1 and 0.571 for ν5 (E) at 1472 cm−1. The total calculated absorption arising from 12CH3D Triad fundamentals is 4.65×10−18 cm−1/(molecule cm−2) at 296 K. In addition, some 740 intensities of nine hotbands are fitted to 8.1%; most of the hotband measurements belong to 2ν6−ν6 and ν3+ν6−ν3…

Absorption spectroscopyChemistryOrganic ChemistryFourier transform spectrometersAnalytical chemistrySpectral responseTriad (anatomy)Spectral lineAnalytical ChemistryInorganic Chemistrymedicine.anatomical_structuremedicineMoleculeAbsorption (electromagnetic radiation)SpectroscopyLine (formation)Journal of Molecular Structure
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EXAFS and XANES Studies of CoxMg1−xO Solid Solutions Using a Laboratory EXAFS Spectrometer

1993

Studies of the local electronic structure and the short-range order in solid solutions CoxMg1−xO with x varying from 0.02 to 1.00 are carried out on the CoK-edge X-ray absorption spectra using a laboratory EXAFS spectrometer. A non-monotonous change of the CoO distance in the first coordination shell with a bent at about x = 0.5 is established. The second coordination shell of cobalt is formed by cobalt and magnesium atoms with a distribution close to a statistical one. [Russian Text Ignored.]

Absorption spectroscopySpectrometerExtended X-ray absorption fine structureInorganic chemistryAnalytical chemistrychemistry.chemical_elementElectronic structureCondensed Matter PhysicsXANESElectronic Optical and Magnetic MaterialsBond lengthchemistryCobaltSolid solutionPhysica Status Solidi (a)
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Vertical Beam Polarization at MAMI

2017

For the first time a vertically polarized electron beam has been used for physics experiments at MAMI in the energy range between 180 and 855 MeV. The beam-normal single-spin asymmetry $A_{\mathrm{n}}$, which is a direct probe of higher-order photon exchange beyond the first Born approximation, has been measured in the reaction $^{12}\mathrm C(\vec e,e')^{12}\mathrm C$. Vertical polarization orientation was necessary to measure this asymmetry with the existing experimental setup. In this paper we describe the procedure to orient the electron polarization vector vertically, and the concept of determining both its magnitude and orientation with the available setup. A sophisticated method has …

Accelerator Physics (physics.acc-ph)Nuclear and High Energy PhysicsPhysics - Instrumentation and DetectorsPhotonmedia_common.quotation_subjectVertical polarization[PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph]FOS: Physical sciencesElectron acceleratorElectronMott polarimeter01 natural sciencesAsymmetrylaw.inventionOpticsMøller polarimeterlaw0103 physical sciencesCompton polarimeter[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det][ PHYS.PHYS.PHYS-ACC-PH ] Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph]Born approximation010306 general physicsNuclear Experiment[ PHYS.PHYS.PHYS-INS-DET ] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]Instrumentationmedia_commonPhysicsWien filter010308 nuclear & particles physicsbusiness.industryParticle acceleratorPolarimeterInstrumentation and Detectors (physics.ins-det)Wien filterPolarization (waves)Electron accelerator ; Vertical polarization ; Wien filter ; Compton polarimeter ; Mott polarimeter ; Møller polarimeterPhysics - Accelerator Physicsbusiness
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Machine Learning approach towards real time assessment of hand-arm vibration risk

2021

In industry 4,0, the establishment of an interconnected environment where human operators cooperate with the machines offers the opportunity for substantially improving the ergonomics and safety conditions of the workplace. This topic is discussed in the paper referring to the vibration risk, which is a well-known cause of work-related pathologies. A wearable device has been developed to collect vibration data and to segment the signals obtained in time windows. A machine learning classifier is then proposed to recognize the worker’s activity and to evaluate the exposure to vibration risks. The experimental results demonstrate the feasibility and effectiveness of the methodology proposed.

AccelerometerArtificial intelligenceActivity recognitionSettore ING-IND/17 - Impianti Industriali MeccaniciVibration risk
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Children's segment specific light physical activity across two years of school-based program

2015

Making sure that children do not sit down for long periods of time can help them perform better in school and to improve their health. The aim of the study was to examine the patterns of children's light physical activity patterns and gender differences through the Physical Activity as Civil Skill Program 2012-2014. The program was designed to create a new physically active school culture, which required changes in psychological and physical school environment. The sample comprised 76 elementary school children at age of 10 to 13-year-old in Northeast-Finland. The data was collected through three measurement phases from October 2012 to April 2014. Accelerometers were used for the objective …

AccelerometerElementary schoolProgrameducationPhysical educationLongitudinalLight physical activity
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Associations of physical activity in detailed intensity ranges with body composition and physical function. a cross-sectional study among sedentary o…

2019

Background Physical activity is crucial to maintain older adults’ health and functioning, but the health benefits of particular activity intensities remain unclear. The aim of this cross-sectional study was to peruse the distribution of physical activity, and to investigate the associations of particular physical activity intensities with body composition and physical function among older adults. Methods The sample comprised of 293 community-dwelling sedentary or at most moderately active older adults (42% men, mean age 74 ± 4 years). Physical activity was measured with a hip-worn tri-axial accelerometer over seven consecutive days, and investigated in detailed intensity range and in catego…

AccelerometerFat percentCommunity-dwellingWalking speedhuman activitiesResearch ArticlePhysical performanceEuropean review of aging and physical activity : official journal of the European Group for Research into Elderly and Physical Activity
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Contribución de la educación física a las recomendaciones diarias de actividad física en adolescentes según el género

2015

Introducción: la institucionalización de la escuela como contexto propicio para el incremento de la actividad física (AF) saludable, la disparidad de resultados en el contexto internacional y la escasez de estudios españoles con medición objetiva en el marco de la Educación Física (EF) hacen necesaria la profundización en esta línea de investigación. Objetivos: los objetivos fueron determinar niveles objetivos de AF durante las clases de EF en adolescentes, comprobar su contribución a la AF diaria recomendable e identificar posibles diferencias según el género. Métodos: una muestra de 337 escolares (211 varones y 183 mujeres), de 13 a 16 años, participaron en esta investigación. La AF se es…

AccelerometerSedentarismActividad física moderada-vigorosaActividad física saludableAcelerómetroSedentarismoStepsHealthy physical activityModerate-to-vigorous physical activityPasos
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Contribución de la educación física a las recomendaciones diarias de actividad física en adolescentes según el género: un estudio con acelerometría

2015

Introducción: la institucionalización de la escuela como contexto propicio para el incremento de la actividad física (AF) saludable, la disparidad de resultados en el contexto internacional y la escasez de estudios españoles con medición objetiva en el marco de la Educación Física (EF) hacen necesaria la profundización en esta línea de investigación. Objetivos: los objetivos fueron determinar niveles objetivos de AF durante las clases de EF en adolescentes, comprobar su contribución a la AF diaria recomendable e identificar posibles diferencias según el género. Métodos: una muestra de 337 escolares (211 varones y 183 mujeres), de 13 a 16 años, participaron en esta investigación. La AF se es…

AccelerometerSedentarismActividad física moderada-vigorosaActividad física saludableAcelerómetroSedentarismoStepsHealthy physical activityModerate-to-vigorous physical activityPasos
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