scholarly journals Validation of UV-visible aerosol optical thickness retrieved from spectroradiometer measurements

2008 ◽  
Vol 8 (1) ◽  
pp. 3895-3919 ◽  
Author(s):  
C. Brogniez ◽  
V. Buchard ◽  
F. Auriol
Keyword(s):  
Wavelength Range ◽  
Optical Thickness ◽  
Aerosol Optical Thickness ◽  
The Other ◽  
Other Hand ◽  
Uv Visible ◽  
Nm Range ◽  
Good Agreement ◽  
Satellite Instruments

Abstract. Global and diffuse UV-visible solar irradiances are routinely measured since 2003 with a spectroradiometer operated by the Laboratoire d'Optique Atmosphérique (LOA) located in Villeneuve d'Ascq, France. The analysis of the direct irradiance derived by cloudless conditions enables retrieving the aerosol optical thickness (AOT) spectrum in the 330–450 nm range. The site hosts also sunphotometers from the AERONET/PHOTONS network performing routinely measurements of the AOT at several wavelengths. On one hand, comparisons between the spectroradiometer and the sunphotometer AOT at 440 nm as well as, when available, at 340 and 380 nm, show good agreement. On the other hand, the AOT's spectral variations have been compared using the Angström exponents derived from AOT data at 340 and 440 nm for both instruments. The comparisons show that this parameter is difficult to retrieve accurately due to the small wavelength range and due to the weak AOT values. Thus, AOT derived at wavelengths outside the spectroradiometer range by means of an extrapolation using the Angström parameter would be of poor value, whereas, spectroradiometer's spectral AOT could be used for direct validation of other AOT, such as those provided by satellite instruments.

scholarly journals Validation of UV-visible aerosol optical thickness retrieved from spectroradiometer measurements

2008 ◽  
Vol 8 (16) ◽  
pp. 4655-4663 ◽  
Author(s):  
C. Brogniez ◽  
V. Buchard ◽  
F. Auriol
Keyword(s):  
Correlation Coefficient ◽  
Wavelength Range ◽  
Optical Thickness ◽  
Regression Line ◽  
Aerosol Optical Thickness ◽  
The Other ◽  
Other Hand ◽  
Uv Visible ◽  
Nm Range ◽  
Good Agreement

Abstract. Global and diffuse UV-visible solar irradiances are routinely measured since 2003 with a spectroradiometer operated by the Laboratoire d'Optique Atmosphérique (LOA) located in Villeneuve d'Ascq, France. The analysis of the direct irradiance derived by cloudless conditions enables retrieving the aerosol optical thickness (AOT) spectrum in the 330–450 nm range. The site hosts also sunphotometers from the AERONET/PHOTONS network performing routinely measurements of the AOT at several wavelengths. On one hand, comparisons between the spectroradiometer and the sunphotometer AOT at 440 nm as well as, when available, at 340 and 380 nm, show good agreement: in 2003–2005 at 440 nm the correlation coefficient, the slope and the intercept of the regression line are [0.97, 0.95, 0.025], and in 2006 at 440, 380 and 340 nm they are [0.97, 1.00, −0.013], [0.97, 0.98, −0.007], and [0.98, 0.98, −0.002] respectively. On the other hand, the AOT's spectral variations have been compared using the Angström exponents derived from AOT data at 340 and 440 nm for both instruments. The comparisons show that this parameter is difficult to retrieve accurately due to the small wavelength range and due to the weak AOT values. Thus, AOT derived at wavelengths outside the spectroradiometer range by means of an extrapolation using the Angström parameter would have large uncertainties, whereas spectroradiometer's spectral AOT could be used for direct validation of other AOT, such as those provided by satellite instruments.

OBSCURANT AND EMISSION CHARACTERISTICS OF THE SCREENING SMOKE COMPOSITIONS USED IN NAVAL SHIPS

2020 ◽  
pp. 108-117
Author(s):  
Toan
Keyword(s):  
Wavelength Range ◽  
Extinction Coefficient ◽  
Infrared Emission ◽  
The Other ◽  
Emission Characteristics ◽  
Red Phosphorus ◽  
Other Hand

Obscurant and optronic decoy compositions are the pyrotechnic formulations that are an effective way to protect naval ships from optical guided missile seekers. In this work, the obscurant characteristics (i.e. the transmittance and the extinction coefficient) and the infrared emission characteristics (i.e. the infrared emission distribution and the radiance) of the obscurant and optronic decoy compositions were described. The results showed that the obscurant cloud made from the mixture of red phosphorus, Ba(NO3)2 and Viton rubber has a low transmittance, high extinction coefficient with 1.06 µm laser and strong infrared emission in the wavelength range of 8.0 to 14.0 µm. On the other hand, the infrared emission radiance (in the wavelength range of 2.5 to 5.0 µm) of the optronic decoy composition based on Mg-Al, hexachloroethane and Viton rubber reaches maximum values (i.e. 17.77E-3 W.cm-2.Sr-1) at about 17 wt% Mg-Al. Finally, the above obscurant and optronic decoy compositions can be used combination in naval ships against the anti-ship missile.

The Separation of Light Gaseous Isotopes by Mass Diffusion Columns II

1964 ◽  
Vol 19 (6) ◽  
pp. 747-755
Author(s):  
W. J. De Wet ◽  
J. Los
Keyword(s):  
Theoretical Analysis ◽  
Mass Diffusion ◽  
Experimental Results ◽  
The Other ◽  
Countercurrent Flow ◽  
Gas Solubility ◽  
Flow Rates ◽  
Mixing Effects ◽  
Other Hand ◽  
Good Agreement

The design of mass diffusion columns operated with partition membranes, for the separation of light gaseous isotopes, is discussed. A theoretical analysis of experimental results obtained indicates that a good agreement between experimental results and theory is only obtained at low column pressures and moderate countercurrent flow rates. At fairly low countercurrent flow rates mixing effects due to viscous dragging and gas solubility by the condensate appear to be considerable whereas excessively high countercurrent flow rates, on the other hand, also seem undesirable. Some suggestions are proposed to obviate impairing effects at least to some extent.

scholarly journals Determination of Relativistic Intensity of X-Ray Diffracted from Aluminum Element.

2019 ◽  
Vol 24 (4) ◽  
pp. 74
Author(s):  
Muhsin Hasan Ali ◽  
Noor Mustafa Fadel
Keyword(s):  
Relative Intensity ◽  
The Other ◽  
X Ray ◽  
Other Hand ◽  
Good Agreement

In this paper, the relative intensity of X-ray diffracted from Aluminum (Al) was found, and taking into account the influences on the intensity of these rays. There was good agreement between the calculated and measured values, the simple differences between them can be attributed to the fact that all crystals in nature are real and not ideal crystals, on the other hand, the accuracy of atomic positions are must probably effected the calculated results   http://dx.doi.org/10.25130/tjps.24.2019.076

Orientation of Prominence Microstructure Relative to the Direction of the Magnetic Field

1979 ◽  
Vol 44 ◽  
pp. 97-101
Author(s):  
O. Engvold ◽  
J.L. Leroy
Keyword(s):  
Magnetic Field ◽  
The Other ◽  
Optical Observations ◽  
High Quality ◽  
Hanle Effect ◽  
Other Hand ◽  
Solar Prominences ◽  
The Magnetic Field ◽  
Good Agreement ◽  
Field Strengths

Recent measurements of the polarization of the Hel D3 line (λ5876Å) in solar prominences (Hanle effect) have been used to infer new data about prominence magnetic field (Leroy 1977, Leroy et al. 1977, Sahal-Brèchot et al. 1977). The derived field strengths are in good agreement with previous magnetographic measurements obtained at several observatories in USA (Rust 1972). Using the Hanle effect also gives the direction of the magnetic field, which is a crusial parameter in theories of prominences (Kippenhahn and Schlüter 1957, Anzer 1968, Malville 1976). Some theories require a horizontal oriented magnetic field in the prominences. High quality optical observations, on the other hand, resolve predominantly vertically oriented prominence microstructure (Dunn 1972, Engvold 1976).

Pb-free solders: Predicting of some physicochemical properties of Ag–Cu–Sn material at different temperatures

2016 ◽  
Vol 15 (07) ◽  
pp. 1650062 ◽  
Author(s):  
Rachida M’chaar ◽  
Mouloud El Moudane ◽  
Abdelaziz Sabbar ◽  
Ahmed Ghanimi
Keyword(s):  
Surface Tension ◽  
Physicochemical Properties ◽  
Molar Volume ◽  
The Other ◽  
Ternary Alloys ◽  
Other Hand ◽  
Different Temperatures ◽  
Experimental Values ◽  
Increasing Temperature ◽  
Good Agreement

In this paper, the surface tension, molar volume and density of liquid Ag–Cu–Sn alloys have been calculated using Kohler, Muggianu, Toop, and Hillert models. In addition, the surface tension and viscosity of the Ag–Cu–Sn ternary alloys at different temperatures have been predicted on the basis of Guggenheim and Seetharaman–Sichen equations, respectively. The results show that density and viscosity decrease with increasing tin and increasing temperature for the all studied models. While the surface tension shows a different tendency, especially for the Kohler and Muggianu symmetric models. On the other hand, the molar volume increases with increase of temperature and tin compositions. The calculated values of surface tension and density of Ag–Cu–Sn alloys are compared with the available experimental values and a good agreement was observed.

Absorption and index of refraction for the modeling of InGaAsP/InP photonic devices

1993 ◽  
Vol 71 (9-10) ◽  
pp. 410-416 ◽  
Author(s):  
B. Reid ◽  
R. Maciejko ◽  
A. Champagne
Keyword(s):  
Experimental Data ◽  
Optical Properties ◽  
Wavelength Range ◽  
Photonic Devices ◽  
Index Of Refraction ◽  
The Other ◽  
Other Hand ◽  
Lattice Matched

Methods for modeling, over an extended practical wavelength range, the index of refraction and the absorption in lattice-matched InGaAsP/InP-based photonic devices are reviewed, completed, and clarified. Carrier-induced effects on the optical properties are given special attention. For the index of refraction, the method gives results within 1% of the experimental ones. On the other hand, the results for absorption are more difficult to compare owing to the lack of experimental data.

Kinetics of Aqueous Alteration of P0798 Simulated Waste Glass in the Presence of Bentonite

2006 ◽  
Vol 932 ◽  
Author(s):  
K. Yamaguchi ◽  
Y. Inagaki ◽  
T. Saruwatari ◽  
K. Idemitsu ◽  
T. Arima ◽  
...  
Keyword(s):  
Secondary Phase ◽  
Model Analysis ◽  
Water Diffusion ◽  
Experimental Results ◽  
The Other ◽  
Protective Effects ◽  
Aqueous Alteration ◽  
Other Hand ◽  
Initial Stage ◽  
Good Agreement

ABSTRACTStatic aqueous alteration tests were performed with a Japanese simulated HLW glass, P0798, in the presence of bentonite in order to understand the effects of bentonite on the glass alteration kinetics and on the associated Cs release. Analogous alteration tests were performed in 0.001M NaOH solution without bentonite for comparison. The results indicated that; 1) at the initial stage of alteration up to 50 days, no remarkable difference was observed in the alteration rate between both cases “with” and “without” bentonite, 2) at the later stage beyond 50 days, however, the rate in the case “with” bentonite was larger than that in the case “without” bentonite. These results on the alteration rate were analyzed by use of a water-diffusion model. In the case “without” bentonite, a good agreement was observed between the model analysis and the experimental results at the initial stage of alteration up to 50 days, however, the model analysis deviated from the experimental results at the later stage beyond 50 days. In the case “with” bentonite, on the other hand, a good agreement was observed even at the later stage to give the value of the apparent diffusion coefficient, Di of 3.5×10−21m2/s. The comparison between both cases suggests that the alteration rate is controlled by the water diffusion in both cases “with” and “without” bentonite, however, the rate is depressed in the case “without” bentonite probably by the protective effects of the alteration layer developing at the glass surface. In the case “with” bentonite, on the other hand, the alteration layer is expected to be less protective. Cesium desorption tests performed for the altered glass and bentonite indicated that most of the cesium dissolved from the glass is retained in the secondary phase of smectite developing in the precipitated layer by sorption with ion-exchange in the case “without” bentonite. In the case “with” bentonite, however, it is likely to be sorbed at bentonite surface.

scholarly journals Chemical taxonomy of the hinge-ligament proteins of bivalves according to their amino acid compositions

1987 ◽  
Vol 242 (2) ◽  
pp. 505-510 ◽  
Author(s):  
Y Kikuchi ◽  
N Tamiya
Keyword(s):  
Amino Acid ◽  
Phylogenetic Relationship ◽  
Pearl Oyster ◽  
The Other ◽  
Amino Acid Compositions ◽  
New Class ◽  
Oyster Species ◽  
Other Hand ◽  
Good Agreement

The proteins in the hinge ligaments of molluscan bivalves were subjected to chemotaxonomic studies according to their amino acid compositions. The hinge-ligament protein is a new class of structure proteins, and this is the first attempt to introduce chemical taxonomy into the systematics of bivalves. The hinge-ligament proteins from morphologically close species, namely mactra (superfamily Mactracea) or scallop (family Pectinidae) species, showed high intraspecific homology in their compositions. On the other hand, inconsistent results were obtained with two types of ligament proteins in pearl oyster species (genus Pinctada). The results of our chemotaxonomic analyses were sometimes in good agreement with the morphological classifications and sometimes inconsistent, implying a complicated phylogenetic relationship among the species.

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