Showing papers on "Haze published in 1969"

Identification of the Venus cloud layers.

Abstract: Venusian atmosphere low reflectivity reinterpretation based on spectrophotometric data indicating constituents of yellow and upper UV haze layers

European brewery convention: haze and foam group. towards the chemical prediction of shelf life

Abstract: Rapid chemical methods are described for assesssing in beer the levels of “oxidizable polyphenols” and “sensitive proteins,” both of which influence non-biological shelf life. The method for oxidizable polyphenols depends on the formation of an insoluble complex with cinchonine sulphate. Freshly processed beers form only a slight haze on the addition of cinchonine sulphate, but the haze produced is greatly increased if the beers are previously oxidized. For beers stabilized by a process involving reduction of the polyphenol content, it is found that the rate of haze formation is then directly related to shelf life and is inversely proportional to it.

European brewery convention—haze and foam group phenolic constituents of beer and brewing materials iv. further observations on anthocyanogens and catechins as haze precursors in beer

Abstract: An earlier supposition that catechins (flavan-3-ols) can favourably influence the stability of a beer by co-polymerizing with flavan-3: 4-diols has been experimentally justified. D-(+)-Catechin, however, is also a direct haze precursor, particularly of chill haze, and its effect is most marked under conditions of high air content when it polymerizes relatively rapidly by an oxidative mechanism. The haze-inducing behaviour of a biflavan anthocyanogen isolated from barley is a little different from that described previously for a very similar anthocyanogen (component 12) from beer. A synthetic 5:7:3′:4′-tetrahydroxyflavan-3:4-diol appears to differ only slightly as a haze precursor from its stereo-isomer, beer component 73. These findings are considered in terms of probable chemical structures. Traces of an anthocyanogen, identical on paper chromatograms with a synthetic 5:7:3′:4′-tetrahydroxyflavan-3:4-diol, and thus stereo-isomeric with beer component 73, are present both in polyamide-beer adsorbates and in barley.

Lidar-Observed Haze Layers Associated with Thermal Structure in the Lower Atmosphere

Abstract: Daytime observations of the vertical temperature and humidity structure in the atmosphere below 1 km made with a Cricketsonde rocket system are compared with simultaneous observations from a ruby lidar (laser radar). Observations were made at the SRI field site in Palo Alto, Calif., during August 1968 in the absence of low clouds when haze and pollution were visually evident. Analyses of the data show a direct relationship between Cricketsonde and lidar data. Invariably, the temperature profile obtained by the Cricketsonde includes a subsidence inversion during the early morning. Either this inversion persists throughout the day or it is destroyed by surface heating, and the temperature lapse approaches the dry adiabat by midafternoon. The lidar observes a deep layer of particulate matter, the upper boundary of which rises in height from morning to afternoon. When a subsidence inversion is observed, the largest change in optical density is detected at the level of the inversion. However, concentr...

Optical doppler measurement of microscale wind velocity

Abstract: A system analysis of the feasibility of optical heterodyne measurement of Doppler shifts as a method for the remote determination of vector wind velocity is carried out. It is found that with a 50-mW laser at 6328 A, naturally occurring aerosols in clear air will permit measurements at distances of only a few tens of centimeters; but haze and dust will extend this range to a few tens of meters and fog to 75 meters. By generating smoke to enhance the scatter, a range of about 40 meters will be achievable. The use of a 1-watt argon laser will extend the clear-air and smoke-plume ranges by a factor of 48 and the ranges in uniform dust or fog by smaller amounts. Hence useful measurements in the boundary layer of the atmosphere are possible although they will require some artificial contamination of the air to give consistently good results. Remote temperature measurement is not possible using this technique.

A study of the effect of haze upon Umkehr measurements

Abstract: The effect of atmospheric haze upon Umkehr observations is calculated in two ways. First, observed Umkehr curves are compared with computed Umkehr curves reconstructed from simultaneous direct soundings of the vertical ozone distribution. The difference between the two curves gives the ‘experimental’ haze effect. In the second method, Umkehr curves are computed for model atmospheres with and without haze, the difference giving a ‘theoretical’ haze effect. When the two haze-effect curves are normalized to zero for a solar zenith angle of 60°, both exhibit the same characteristics, viz., the ‘correction’ to be subtracted from an observed (with haze) curve is negative at all solar zenith angles, the correction reaches a maximum near 81°, and there is a second small reversal near 87–88°. Application of the derived haze corrections in the Umkehr evaluation procedure results in slightly higher ozone content at and just below the main maximum and slightly lower ozone content elsewhere.

Effect of changes in complex part of the refractive index on polarization of light scattered from haze and clouds.

Abstract: The polarization and radiance of the reflected and transmitted radiation is calculated for a continental haze model and for a nimbostratus cloud model. The complex part- of the index of refraction n2 is varied from 0 to 1 in the calculation. Various surface albedos and optical thicknesses for the haze and cloud are considered. The polarization is an especially sensitive function of these parameters. For a thin cloud the reflected polarization depends strongly on the surface albedo. Large polarizations often occur, even at large optical thicknesses, when the single scattering albedo is small, because of the small number of multiple scattered photons. The mean optical path, diffuse flux, and cloud albedo are also discussed.

Observations on Beer Haze

Abstract: (1969). Observations on Beer Haze. Proceedings. Annual meeting - American Society of Brewing Chemists: Vol. 27, Proceedings of the Annual Meeting 1969, pp. 142-148.