True polarization curves for Beta Lyrae.
Beta Lyrae intrinsic polarization amount and phase dependence in visual, blue and UV light observed, analyzing polarization curves
ECLIPSING BINARY STAR↗
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The polarization curve and the absolute diameter of Vesta
Photoelectric polarization curve, reflectivity and absolute diameter of Vesta, comparing with Lyot curve
Veverka, J.↗
Analytical methods for computing the polar curves of airplanes
This report presents a method of calculating polar curves which is at least as precise as graphical methods, but it more rapid. Knowing the wind tunnel test of a wing and the performances of an airplane of the same profile, it is easy to verify the characteristic coefficients and, at the same time, the methods determining induced resistances.
LE SUEUR↗
Observations of structure in the interstellar polarization curve Preliminary results
We have measured the wavelength dependence of the interstellar polarization curve with higher wavelength resolution than has generally been used before. Our data show structure which has been previously unknown, and which may have important implications with respect to the composition of the interstellar grains. It is similar in general form to structure predicted on the basis of a theoretical model designed by us to give a detailed match to the extinction structure.
Mavko, G. E.↗
Asteroid reflectivities from polarization curves - Calibration of the 'slope-albedo' relationship.
The relationship between h, the slope of the positive branch of a polarization curve, and A, the normal reflectance of the surface, has been calibrated using a wide range of published data. It is determined that asteroid albedos can be inferred meaningfully by this method without prior knowledge of the detailed mineralogical composition of asteroid surfaces.
Veverka, J.↗
Interpretation of the brightness and polarization curves of the moon
Theoretical models for lunar brightness at small phase angles and polarization of moonlight
POLARIZATION↗
New Method of Determining the Polar Curve of an Airplane in Flight
A fundamental defect of existing methods for the determination of the polar of an airplane in flight is the impossibility of obtaining the thrust or the resistance of the propeller for any type airplane with any type engine. The new method is based on the premise that for zero propeller thrust the mean angle of attack of the blade is approximately the same for all propellers if this angle is reckoned from the aerodynamic chord of the profile section. This angle was determined from flight tests. Knowing the mean angle of the blade setting the angle of attack of the propeller blade at zero thrust can be found and the propeller speed in gliding obtained. The experimental check of the new method carried out on several airplanes gave positive results. The basic assumptions for the construction of the polars and the method of analyzing the flight data are given.
Yegorov, B. N.↗
Stress Corrosion Cracking of titanium alloys - Electrochemical kinetics, SCC studies with Ti-8-1-1, SCC and polarization curves in molten salts, liquid metal embrittlement, and SCC studies with other titanium alloys Quarterly progress report, period ending 31 Dec. 1969
Stress corrosion cracking behavior in titanium, molybdenum, and aluminum alloys, and electrochemical kinetic studies
Beck, T. R.↗
The logarithmic polar curve-it's theory and application to the predetermination of airplane performance
The logarithmic polar curve has for several years been used by the most prominent aerodynamical laboratories as well as by airplane manufacturers in Europe. To show more clearly the practical application of the polar curve, a series of examples are given with suggestions for solution. After a discussion of the theory and the practical application of the polar curve, the following problems are discussed: climbing flight, speed at various altitudes, and the characteristics of two seater observation airplanes of recent design.
Cronstedt, Val↗
A study of the asymmetric wind of P Cygni
Results of optical linear spectropolarimetric measurements of the hypergiant P Cygni are presented. The data indicate that both the intrinsic polarization and the position angle vary with time. It is found that, prior to removing the interstellar polarization vector, the polarization varies by 0.642 percent, while the position angle takes on values between 27.0 and 39.8 deg. The wavelength dependence of the polarization curve also changes with time, indicating that the intrinsic polarization curve is not always constant with the wavelength. After a model is determined for interstellar polarization, it is found that the amplitude of the intrinsic polarization of P Cyg varies from 0.04 to 0.48 percent, with a change of 0.12 percent on successive nights. It is inferred from this large variation in the polarization on such a short timescale that the scattering material lies close to the star. Several possible geometries to describe the circumstellar material of P Cygni are presented.
Taylor, M.↗
Wing resistance near the ground
In the present treatise, a convenient method will be indicated, which makes it possible to determine the polar curve of an airplane at short distances from the ground by a simple short calculation, when the polar curve is known for flight in unlimited space.
GROUND EFFECT↗
Electrochemical approach for passivating steel and other metals and for the simultaneous production of a biocide to render water potable
Potentiostatic polarization curves indicated that the cathodic reactions in deaerated KI-I2 water solutions were due to iodine reduction and hydrogen evolution. In the presence of oxygen an additional reduction wave appeared. Anodic polarization curves revealed that iodine could be produced in the region of potential from +600 to +1000 nv vs. SCE.
Source record↗
Polarimetric observations of 9 Metis, 15 Eunomia, 89 Julia, and other asteroids.
White-light polarization curves for a number of asteorids are presented. All have well-developed negative branches, suggestive of relatively dark, texturally complex surfaces - possibly regoliths. Geometric albedos, estimated from the positive branch of the polarization curves, show that a significant dispersion in surface albedo exists within the asteroid belt.
Veverka, J.↗
Photopolarimetric observations of the minor planet Flora.
Review of the rotation period, phase coefficients, and polarization curve of the unusual asteroid Flora. It is an almost spherical asteroid whose period of rotation is probably 13.6 h, but may be only one half of this. Its surface layer consists of a dark material resembling lunar surface soil, but since the polarization curves of Flora and the moon, though generally similar, are not identical the surface of Flora must differ somewhat either in composition or in texture from that of the moon.
Veverka, J.↗
Minor planets and related objects. IX - Photometry and polarimetry of /1685/ Toro.
UBV photometry, lightcurves, a polarization-phase relation, and rotational polarization curves of Toro were obtained, June-August 1972. The average colors are B-V = 0.87 and U-B = 0.47 mag, showing some reddening with phase. The geometric albedo of Toro in the B filter is 0.14 which corresponds to an effective mean radius of 2.2 km plus or minus 0.4 (p.e.). The rotational polarization curves indicate that the lightcurves are mostly due to shape, but some albedo variation over the surface is detected as well. The shape is elongated, and probably irregular, with a cross-sectional area ratio of about 3.2, the maximum effective radius is 2.8 km and the minimum, 1.6 km.
Dunlap, J. L.↗
Airborne infrared polarimetry.
An airborne remote sensing study of cloud particle sizes and shapes, performed with an IR polarimeter is described. Linear polarization for a given wavelength was measured as a function of the phase angle. Liquid water clouds are found to exhibit considerable detail in their polarization curves, including a positive cloudbow near 40-degrees phase angle, and negative polarization at phase angles of less than 20 degrees and greater than (roughly) 100 degrees. A polarization vs phase angle curve obtained for thick tropical cirrus clouds showed negative polarization at large and small phase angles, and positive polarization at angles between 20 and 145 degrees. There is no indication of a cloudbow or other detailed structure.
Coffeen, D. L.↗
A harmonized protocol to assess the single-cell performance of proton exchange membrane water electrolyzers
The harmonization of testing protocols for proton exchange membrane (PEM) electrolyzers is essential for ensuring accurate and reliable performance assessments and accelerating the development of hydrogen production technologies. This protocol provides a structured approach to PEM electrolyzer setup and testing, incorporating key considerations for test station design and single-cell characterization techniques. Polarization curves and electrochemical impedance spectroscopy (EIS) are detailed, along with best practices from academic and industry research groups to enhance data accuracy and comparability. By addressing material variability and harmonizing testing methodologies, this framework enables more precise evaluations of membrane electrode assemblies and electrolyzer components. Harmonized protocols not only streamline development efforts but also foster collaboration across institutions, ultimately supporting the commercialization of hydrogen solutions through improved stack efficiency and durability.
08 HYDROGEN↗
Photo-polarization study of lunar samples: Negative branch
Polarization measurements with a telescope for the degree of polarization of light reflected by planetary surfaces, and comparative measurement of terrestrial minerals, meteorites, and returned lunar samples are reported. The polarization curve plots of the dependence of the degree of polarization on the phase angle V are plotted and compared with each other to determine the optical characteristics of the planetary surfaces.
Dollfus, A.↗