FIELD-INDUCED ABSORPTION IN HYDROGEN

1958 ◽  
Vol 36 (8) ◽  
pp. 1022-1039 ◽  
Author(s):  
M. F. Crawford ◽  
R. E. MacDonald
Keyword(s):  
Matrix Element ◽  
High Field ◽  
Mean Value ◽  
Absorption Coefficients ◽  
High Field Strength ◽  
Vibration Absorption ◽  
The Matrix ◽  
The Mean ◽  
Experimental Values ◽  
Good Agreement

This paper reports an investigation of the fundamental rotation–vibration absorption induced in hydrogen by an electric field. The integrated absorption coefficients of the first four components of the Q branch have been measured for a range of field strengths at densities of 83.9 and 44.6 Amagat. The integrated absorption coefficient of the S(1) line has been determined at the higher density for one high field strength. The relative intensities of the Q components are in good agreement with the predicted ratios. Accurate experimental values of the matrix element of the mean value of the polarizability, (α)01, and the matrix element of its anisotropy, (γ)01 have been obtained. They are: (α)01 = 0.968 × 10−25 cm3, and (γ)01 = 0.72 × 10−25 cm3 at 83.9 Amagat, and are only slightly dependent on density. The frequencies of the lines have been measured. Only Q(1) and S(1) show a measurable shift with density. The optical collision diameter has been determined and is very small, 0.26 Å.

scholarly journals Optical Properties of Dissolved Organic Matter in Finnish and Estonian Lakes

2003 ◽  
Vol 34 (4) ◽  
pp. 361-386 ◽  
Author(s):  
L. Sipelgas ◽  
H. Arst ◽  
K. Kallio ◽  
A. Erm ◽  
P. Oja ◽  
...  
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Natural Waters ◽  
Mean Value ◽  
Published Data ◽  
Optical Parameters ◽  
Exponential Approximation ◽  
Absorption Coefficients ◽  
Specific Absorption ◽  
The Mean

The main objective of the present study is to test various methods for describing the absorption spectra of coloured dissolved organic matter (CDOM) and to determine the numerical values of some optical parameters of CDOM in lakes with diverse water quality. First, the parameters of an exponential model in different spectral intervals were determined. In addition, the suitability of some other models for the approximation of CDOM spectra was estimated. Specific absorption coefficients of CDOM were calculated from the absorption coefficients and dissolved organic carbon (DOC) concentrations. The experimental initial data were differences between spectral attenuation coefficients of filtered and distilled water. Two datasets were used: 1) for 13 Estonian and 7 Finnish lakes (altogether 404 spectra between 350 and 700 nm) measured by the Estonian Marine Institute (EMI); 2) for 10 Finnish lakes (73 spectra) measured by the Finnish Environment Institute (FEI). The spectra of CDOM absorption coefficients (aCDOM) were calculated from experimental data taking into account the correction due to scattering properties of colloids in the filtered water. The total content of CDOM in natural waters of Estonian and Finnish lakes was expressed by means of aCDOM at the wavelength of 380 nm. It varied significantly, from 0.71 to 19.5 m−1, the mean value (of all the investigated lakes) being around 6.6 m−1. Slopes of the exponential approximation varied widely, from 0.006 to 0.03 nm−1. Averaged over all lakes values of slope for the interval 380-500 nm obtained from the EMI dataset are close to those obtained from the FEI dataset: from 0.014 nm−1 (without correction) to 0.016-0.017 nm-1 (with different types of correction). These results are in good correspondence with most published data. Attempts to describe the spectra in the region of 350-700 nm by means of hyperexponential functions (∽ exp(-αλη)) show that: (1) η < 1 (in the case of traditional exponential approximation η = 1); (2) a promising idea is to seek the best fit only for wavelengths λ > λ1, where λ1 will be chosen taking into account the real shape of aCDOM spectra. The mean value of the specific absorption coefficient (a*CDOM) at the wavelength 380 nm obtained in this study (0.44 L mg−1 m−1) is close to the values published in the literature, if we assume that a*CDOM (380) is calculated using the data of dissolved organic matter (DOM). The optically non-active fraction of DOM in our study was high and therefore a*CDOM (380) was considerably higher (1.01 L mg−1 m−1) than a*CDOM (380). The results of the present work could be used in the modeling of underwater light field as well as in the interpretation of radiation measurements and optical remote sensing results.

scholarly journals An improved transmitter system to accurately measure wet-bulb temperature of air

2019 ◽  
Vol 52 (7-8) ◽  
pp. 1002-1007
Author(s):  
Liangwen Yan ◽  
Peng Yu ◽  
Sijung Hu ◽  
Qiu Gao ◽  
Wei Li ◽  
...  
Keyword(s):  
Real Time ◽  
Latent Heat ◽  
Measurement Accuracy ◽  
Cost Effective ◽  
Mean Value ◽  
Experimental Results ◽  
Iteration Algorithm ◽  
Good Consistency ◽  
The Mean ◽  
Good Agreement

A cost-effective measurement of wet-bulb temperature of air has great benefits to fulfill a growing demand of industry, cultivation agriculture, and medication. Applying an appropriate algorithm to wet-bulb temperature of air measurement can effectively improve the accuracy and speed of its measurement. The study aims to research how an improved transmitter system along with the latent heat–based iteration algorithm is used to precisely measure wet-bulb temperature of air. The work consists of (1) simulation of the iteration algorithm and (2) validation via experimental protocol. The simulation results through latent heat–based iteration algorithm were in good agreement ( R2≥ 0.99) with the reference. The performance of the improved wet-bulb temperature of air transmitter system was tested by a latent heat–based iteration algorithm experimental setup. The experimental results demonstrate that the improved wet-bulb temperature of air in a good consistency with commercial wet-bulb temperature of air in a range of temperature (15°C–34°C) and relative humidity (28.8%–76.2%). The Bland–Altman plot also shows that the mean value and the standard deviation of the differences between these two systems are 0.14°C and 0.29°C, respectively, which indicates that the improved wet-bulb temperature of air has a good agreement as well. Compared with the commercial wet-bulb temperature of air transmitter system, an advanced processor (STM32F103C8T6) and real-time operating system was applied in the improved wet-bulb temperature of air transmitter system. The experimental results show that its measurement accuracy is closer to the previous study. This study provides an alternative and cost-effective solution to accurately and real-time measure wet-bulb temperature of air.

scholarly journals Neutral Saturated Lapse Rate: An Experimental Check from CALJET-1998 and PACJET-2001

2009 ◽  
Vol 137 (12) ◽  
pp. 4382-4385 ◽  
Author(s):  
Renzo Richiardone ◽  
Massimiliano Manfrin
Keyword(s):  
High Resolution ◽  
Normal Distribution ◽  
Mean Value ◽  
Lapse Rate ◽  
Temperature Profiles ◽  
Experimental Check ◽  
Rate Distribution ◽  
The Mean ◽  
Lapse Rates ◽  
Good Agreement

Abstract The lapse rates of high-resolution temperature profiles during nearly neutral, saturated conditions are compared with the saturated adiabatic lapse rate and with that proposed by Richiardone and Giusti. A good agreement between the latter and the mean value of the observed lapse rate is found, whereas the saturated adiabatic lapse rate differs significantly, confirming experimentally that it is not completely correct to assess the moist neutrality from a comparison with the saturated adiabatic lapse rate. The lapse-rate distribution supports the hypothesis that the lapse-rate statistics is a local collection of saturated adiabatic lapse rates in a background normal distribution centered around the neutrality.

scholarly journals Discussion of Methods on Determining the Mean Matter Density of the Universe

1978 ◽  
Vol 79 ◽  
pp. 281-286
Keyword(s):  
Mass Density ◽  
Mean Value ◽  
Matter Density ◽  
Future Prospects ◽  
The Mean ◽  
Conventional Methods ◽  
The Universe ◽  
Good Agreement

Tammann: The question of the mean mass density in the Universe has been mentioned many times and the organisers thought it would be useful to look at future prospects for obtaining improved estimates of Ω. the methods may be split into two types. First, the conventional methods involve determining the luminosity density in the Universe and multiplying by an appropriate mass-to-luminosity ratio. It must be emphasised that the mass determinations are dynamical and that most of the mass is not visible. There is good agreement among independent workers about the luminosity density and this figure seems to be known within a factor of 2. the appropriate mean value of M/L is more controversial, values between 10 and 200 having been discussed in the preceding lectures. It is agreed, however, that if the mean value of M/L lies in this range, one cannot close the Universe. Perhaps one should be more cautious and say that even granted the uncertainties in the quantities involved, it is unlikely that the Universe is closed.

Interassay Differences in Growth Hormone Measurement in Acromegaly

1997 ◽  
Vol 34 (2) ◽  
pp. 156-159 ◽  
Author(s):  
J H Barth ◽  
J H Smith ◽  
P Clarkson
Keyword(s):  
Growth Hormone ◽  
Mean Value ◽  
Consistent Difference ◽  
Plasma Samples ◽  
Plasma Growth Hormone ◽  
Gh Isoforms ◽  
The Mean ◽  
Good Agreement

We measured plasma growth hormone concentrations by three different two-site immunometric assays (Pharmacia hGH RIA, IDS Gamma-BCT and Delfia 22 kDa hGH) to determine whether there are GH isoforms secreted by acromegalic patients that are under-recognized by some assays. There was a fairly good agreement between assays with the IDS Gamma-BCT and Delfia 22 kDa assays giving lower results than the Pharmacia IRMA. GH was measured on stored plasma samples from 24 patients with proven acromegaly. There was a consistent difference between the three assays of approximately 20% of the mean value for each patient.

Polarization and Decay of Fluorescence of Solutions

1963 ◽  
Vol 18 (6) ◽  
pp. 718-724 ◽  
Author(s):  
R. K. Bauer
Keyword(s):  
Ethyl Alcohol ◽  
Solvation Shell ◽  
Exciting Light ◽  
Emission Anisotropy ◽  
The Mean ◽  
Experimental Values ◽  
Alcohol Ethyl ◽  
Dye Solutions ◽  
Good Agreement ◽  
Dye Molecule

Measurements of the polarization and the mean decay periods τ∥ and τ⟂ of fluorescence components I∥ and I⟂ parallel and perpendicular to the electric vector of plane polarized exciting light were performed for uranin dye solutions in glycerol diluted with methyl alcohol, ethyl alcohol and water. From these measurements the volume ν of the dye molecule together with its solvation shell and the limiting emission anisotropy r0 for solutions of various viscosities were calculated. Both ν and r0 appeared to be in general not constant and dependent on the nature of the solvent. If, as observed in one case, ν and r0o are substantially constant, a good agreement between experimental values τ∥/τ and τ⟂/τ and those evaluated from the equations of JABLONSKI is obtained (τ being the mean duration of the fluorescence emitted in all directions).

scholarly journals Estimation of Rabbit Pancreas Dispersion Between 400 and 1000 nm

2021 ◽  
Vol 7 (2) ◽  
pp. 020303
Author(s):  
Inês Martins ◽  
Hugo Silva ◽  
Valery Tuchin ◽  
Luís Oliveira
Keyword(s):  
Total Internal Reflection ◽  
Mean Value ◽  
Reflection Method ◽  
Porcine Pancreas ◽  
Rabbit Pancreas ◽  
Deep Ultraviolet ◽  
The Mean ◽  
The One ◽  
Fitting In ◽  
Good Agreement

Current biophotonics methods cover the entire optical spectrum from the deep ultraviolet to the terahertz. To optimize such methods for diagnostic and therapeutic applications, the need to obtain the wideband dispersion of tissues is high. The pancreas is a very important organ in the human body, since it produces insulin and its malfunction may induce diabetes. A reduced number of biophotonics publications regarding the pancreas is available, meaning that studies to determine its optical properties and their variation during optical clearing treatments are necessary. Considering this fact, we used the total internal reflection method to measure the refractive index of the rabbit pancreas for wavelengths between 400 and 850 nm. The experimental results allowed to calculate the pancreas dispersion with the Cauchy, Conrady and Cornu equations. It was observed that all those equations provided good data fitting in the spectral range of the measurements, but differences were observed outside these limits. Considering the wavelength of 633 nm, the mean value from the three dispersions was 1.3521, while the one published for porcine pancreas is 1.3517. The dispersion calculated with the Conrady equation does not present a fast decreasing behavior for shorter wavelengths as the ones calculated with the Cauchy and Cornu equations, but comparing these curves with a dispersion for a tissue-like material, all seem to have good agreement.

scholarly journals DETERMINATION OF THE URANIUM CONTENT IN SOME SOIL SAMPLES FROM AJAOKUTA, KOGI STATE: NIGERIA

2019 ◽  
Vol 7 (9) ◽  
pp. 252-258
Author(s):  
Aruwa Arome ◽  
Philibus Musa Gyuk ◽  
Achor Mathias Ogwo ◽  
Isah Suleiman
Keyword(s):  
Activity Concentration ◽  
Pulse Height ◽  
Uranium Content ◽  
Mean Value ◽  
Soil Samples ◽  
Pulse Height Analyzer ◽  
The World ◽  
The Mean ◽  
Good Agreement

This work present the Uranium (238U) content in soil samples collected in Ajaokuta from some villages was been determined. The measurement of the soil Uranium activity concentration were made using a multi–channel pulse height analyzer (Camberra series 10 plus) coupled to a 76.2mm x 76.2mm NaI (TI) scintillation detector. 2.93)The mean Uranium content in the analyzed samples was found to be (44.26 Bq/kg which is higher than the world mean value of 35Bq/kg. The results were in good agreement with others for soils from region which is considered as normal or slightly high in radioactivity level.

scholarly journals A Thermochemical Computational Study on Hydroxyquinolines and their Azulene Analogues

2018 ◽  
Author(s):  
Moyassar Meshhal ◽  
Safinaz El-Demerdash ◽  
Ahmed El-Nahas
Keyword(s):  
Gas Phase ◽  
Computational Study ◽  
Enthalpies Of Formation ◽  
Mean Absolute Deviation ◽  
Electron Affinities ◽  
Absolute Deviation ◽  
The Mean ◽  
Experimental Values ◽  
Theory And Experiment ◽  
Good Agreement

Ab initio CBS-QB3 method has been used to determine gas-phase enthalpies of formation for 34 compounds including a number of hydroxyquinoline isomers, the corresponding azulene analogues and their parent systems. The mean absolute deviation of 4.43 kJ/mol reveals good agreement between our results and the available experimental data. Relative thermodynamic stabilities of hydroxyquinoline isomers and related analogues were discussed and several isomerization reactions enthalpies were derived. The same level of theory has also been utilized to calculate adiabatic ionization energies and electron affinities for the molecules with known experimental values and the agreement between theory and experiment was found to be within 8 kJ/mol.

Major scattering processes

2020 ◽  
pp. 379-416
Author(s):  
Sandip Tiwari
Keyword(s):  
Matrix Element ◽  
Cross Section ◽  
High Field ◽  
Phonon Scattering ◽  
Quantum Mechanical ◽  
Coulomb Scattering ◽  
Particle Interactions ◽  
Relative Importance ◽  
Scattering Cross ◽  
The Matrix

This chapter discusses major scattering processes found in semiconductors, including phonon scattering (deformation scattering, piezoelectric scattering, polar scattering and non-polar scattering), scattering arising from impurities (charged, so a Coulomb scattering, and charge neutral) and scattering arising in compositional randomness, from carrier-carrier events and due to coupled-particle interactions. The discussion starts by making connections between the classical scattering cross-section and its quantum-mechanical origins through the matrix elements for scattering. The ability to write the matrix element is employed for describing scattering by phonons in its various forms, for impurities and their various levels of accuracy of the description. Umklapp processes are described. When multiple scattering processes are present, the resulting transport manifests the processes’ independence and dependence. With an understanding of the scattering, observed behavior in semiconductors of interest is summarized to show their relative importance. The chapter concludes by discussing frequency and high field behavior manifested by electron ensembles.

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