Phase-stepping : New Algorithm Immune to Linear Reference Phase Error

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An Innovative Gas Sensor with On-Chip Reference Using Monolithic Twin Laser

An innovative gas sensor with on-chip reference using a monolithic twin laser is proposed. In this sensor a monolithic twin laser generates two closer laser beams with slight different wavelengths alternatively, one photodiode is used to catch both absorption and reference signals by time division multiplexing. The detection of nitrous oxide adopting this scheme using a 2.1μm antimonide laser and an InGaAs photodiode has been demonstrated experimentally with detection limit below 1ppm. Using this on chip reference scheme the fluctuations from the optical path and devices can be compensated effectively; the sensor system is simplified distinctly.     

Establishing a Private Shared Reference Frame via the Distillation of Entanglement

We show that there is a contradiction within quantum mechanics. We derive a proposition concerning a quantum expectation value under the assumption of the existence of the directions in a spin-1/2 system. The quantum predictions within the formalism of von Neumann’s projective measurement cannot coexist with the proposition concerning the existence of the directions. Therefore, we have to give up either the existence of the directions or the formalism of von Neumann’s projective measurement. Hence there is a contradiction within the Hilbert space formalism of the quantum theory. This implies that there is no axiomatic system for the quantum theory. We need new physical theories in order to explain mathematically the handing of raw experimental data.     

Reference Spectra in the “Artificial-Moon” Scale and Cosmological Studies of Radio Sources

We present the modified version of the flux scale [1] of cosmic radio sources. The number of standard sources is increased, the dynamical range of the scale is extended by one order of magnitude toward weak fluxes, and the standard sources are distributed more uniformly over the northern hemisphere. The scale [1] at frequencies above 15 GHz is improved with allowance for additional data. New standard sources are determined in the millimeter wavelength range. The spectra of standard sources are obtained on the basis of accurate absolute measurements of the radiation flux density at frequencies 0.5-10 GHz by the method of an artificial moon. Spectrum shapes of the standard sources were determined by the method of relative spectra based on relative measurements in the frequency interval from 26 MHz to 31.4 GHz. This makes it possible to find spectra in the entire frequency range with an accuracy of 3-4%. We determined the spectra of more than 100 steep-spectrum extra-Galactic sources in the artificial-moon' scale. Most spectra have breaks in the frequency interval from 178 MHz to 14.9 GHz. The spectra of some sources have constant spectral indices. The distributions of the break frequencies of radio galaxies and quasars over celestial coordinates of these sources are obtained. These distributions are close to lognormal. The frequencies of the maxima of radio-galaxy and quasar distributions are equal to 1.25 and 2.5 GHz, respectively. The mean spectral indices as functions of frequency are determined for radio galaxies and quasars. The spectral indices of sources belonging to these two groups increase with frequency at the same rate below 3 GHz. At higher frequencies, the slope of the mean spectrum of galaxies remains the same, while the mean quasar spectrum flattens.     

Darboux Transformation Method for Solving the Sime—Gordon Equation in a Laboratory Reference

The sine-Gordon equation is solved in a laboratory reference using the method of Darboux transformation.Using the Liouville theorem,explicit expressions of the single soliton solution and the breather solution are derived from the Darboux matrix in the case of a null spectral parameter.     

Six-frame Algorithm Insensitive to the Linear Reference Phase and Detector Nonlinearity Errors for Phase-stepping Interferometry

l.IntroductionForphase-stepping(orphase-shifting)interferometrytherearetwomainsourcesoferror:thereferencephaseerrorandthenonlinearerrorofdetector.Inearlyresearch,onlyCarreISalgorithm[1]cancompletelyeliminatethelinearreferencephaseerroriftheinterferogramsaresampledintermsofthesamephaseshiftinginterval.Recemtly,manya1gorithmshavebeendeveloPedtoreducethesetwoerrorsources.J.SchmitandK.Creath[2Jusedanextendedaveragingtechniquetoobtainasetoferror-comPensatingalgo-rithmsthatareinsensitivetothelin…     

Radiation Laws of a Kerr Nonlinear Blackbody in a Moving Frame of Reference

A Kerr nonlinear blackbody (KNB) is a new kind of blackbody in which bare photons with opposite wave vectors and helicities are bound into pairs and unpaired photons are transformed into nonpolaritons. In the present paper, the radiation of a KNB is considered from the viewpoint of an observer in arbitrary uniform motion with respect to a rest frame of reference of the radiation. It is found that the radiation laws, which include the distribution of nonpolaritons and so forth, are modified due to the motion. Moreover, under a special condition, we notice that the only effect of the motion is to introduce an angle-dependent directional temperature, which replaces the rest-frame temperature of the cavity. Besides, we try to extend the model of a KNB to the whole Universe and apply the modified radiation laws to the question of 2.7 K cosmic microwave background radiation (CMBR).     

Round-robin measurements of two candidate materials for a Seebeck coefficient Standard Reference Material™

A Standard Reference Material (SRM^™) for the Seebeck coefficient is critical for inter-laboratory data comparison and for instrument calibration. To develop this SRM^™, we have conducted an international round-robin measurement survey of two candidate materials—undoped Bi₂Te₃ and constantan (55% Cu and 45% Ni alloy). Measurements were performed in two rounds by twelve laboratories involved in active thermoelectric research using a number of commercial and custom-built measurement systems and techniques. We report the results of these measurements and the statistical analysis performed. Based on this extensive study, we have selected Bi₂Te₃ as the prototype standard material.     

Tetrad Fields,Reference Frames,and the Gravitational Energy–Momentum in the Teleparallel Equivalent of General Relativity

The concept and definitions of the energy–momentum and angular momentum of the gravitational field in the teleparallel equivalent of general relativity (TEGR) are reviewed. The importance of these definitions is justified by three major reasons. First, the TEGR is a well established and widely accepted formulation of the gravitational field, whose basic field strength is the torsion tensor of the Weitzenböck connection. Second, in the phase space of the TEGR there exists an algebra of the Poincaré group. Not only the definitions of the gravitational energy–momentum and 4-angular momentum satisfy this algebra, but also the first class constraints related to these definitions satisfy the algebra. And third, numerous applications of these definitions lead to physically consistent results. These definitions follow from a well established Hamiltonian formulation, and rely on the idea of localization of the gravitational energy. In this review, the concept of localizability of the gravitational energy is revisited, in light of results obtained in recent years. The behavior of free particles is studied in the space–time of plane fronted gravitational waves (pp-waves). Free particles are here understood as particles that are not subject to external forces other than the gravitational acceleration due to pp-waves. Since these particles acquire or loose kinetic energy locally, the transfer of energy from or to the gravitational field must also be localized. This theoretical result is considered an important and definite argument in favor of the localization of the gravitational energy–momentum, and by extension, of the gravitational 4-angular momentum.     

Ultrasonic Extraction–Ozonation Sequential Sample Treatment for the Determination of Arsenic in Environmental Certified Reference Materials by Hydride Generation–Atomic Fluorescence Spectrometry

Abstract

A sample pretreatment method based on ultrasound‐assisted extraction followed by ozonation is developed for sensitive determination of total As in biological and environmental certified reference materials and an unknown plant sample (Acacia dealbata) by flow injection and continuous‐flow hydride generation–atomic fluorescence spectrometry. The method is meant to minimize the use of corrosive and oxidizing acids for sample decomposition and common errors in trace analysis. Problems derived from introduction of sonicated extracts in continuous flow and flow injection manifolds in combination with an atomic fluorescence detector, such as excessive foaming and flame instability, are addressed. The following certified reference materials (CRMs) were employed for method assessment: BCR CRM 482 lichen; BCR CRM 60 and 61 aquatic plants; BCR CRM 279 sea lettuce; NIST 1633b fly ash; BCR 320 river sediment; RTC CRM 024‐050 soil. Effect of variables such as extraction time, ultrasound amplitude, concentration of extractant acid, sample mass, drying mode, and particle size was investigated. Leaves of Acacia dealbata were also employed for method development. Limits of detection ranged from 0.03 to 0.15 µg/g As depending on the sample. Between‐batch precision values ranged from 2% to 11%. Sample throughput was 40 hr^?1 with flow injection.     

Synthesis of a New Thermal and Photostable Reference Probe for Qf Measurement in Aqua: Water Soluble N,N′-bis-(2-Hydroxy-4-benzoic Acid)-3,4,9,10-perylenebis(dicarboximide)

N,N′-bis(2-hydroxy-4-benzoic acid)-3,4,9,10-perylenebis(dicarboximide) is synthesized from perylene 3,4,9,10-tetracarboxylic dianhydride and 4-amino-3-hydroxy benzoic acid in 90% yield. Together with the photostability the dye is also very stable thermally. The fluorescence quantum yield is measured as one, Q_f=1.The diimide dissolves in water at PH = 8 completely. The diimide is an ideal reference probe for fluorescence quantum yield measurements in 500–650 nm region and an attractive photosensitizer for the photoreactions occur in water.