scholarly journals THEORY ON THE DETERMINATION OF THE WORK PLANE ILLUMINANCE BY DAYLIGHT INCLUDING DIRECT SUNLIGHT THROUGH WINDOWS WITH REFLECTIVE LOUVERS OR VENETIAN BLINDS

1982 ◽  
Vol 321 (0) ◽  
pp. 108-116 ◽  
Author(s):  
MASANORI SHUKUYA ◽  
KEN-ICHI KIMURA
Keyword(s):  
Direct Sunlight ◽  
Venetian Blinds

On the diathermancy of Antimonite

1903 ◽  
Vol 13 (62) ◽  
pp. 342-347
Author(s):  
A. Hutchinson
Keyword(s):  
Cleavage Surface ◽  
Direct Sunlight ◽  
Orthorhombic System ◽  
Elliptic Polarization ◽  
Polarization Of Light

A determination of the constants of elliptic polarization of light reflected from a fresh cleavage surface of antimonite enabled Professor P. Drude to calculate two of the indices of refraction of this substance as 5.17 and 4.49 respectively. Instead, however, of the symmetry-axes of the crystal, regarded as belonging to the orthorhombic system, coinciding with the principal vibration directions in the plane (010), he found that the latter were inclined to the former lines at angles which varied in different observations between 2.6° and 15.4°. These observations, which indicate that the symmetry of antimonite is of the oblique or anorthie type, stand in opposition to those of Professor O. Mügge, who found that exceedingly thin flakes of antimonite placed between crossed nicols in direct sunlight transmitted sufficient light of a deep red colour to enable him to determine the extinction as straight.

scholarly journals VII. Photo-chemical researches.—Part V. On the direct measurement of the chemical action of sunlight

1863 ◽  
Vol 153 ◽  
pp. 139-160 ◽  
Keyword(s):  
Direct Measurement ◽  
Royal Society ◽  
Time Of Day ◽  
Direct Sunlight ◽  
Chemical Action ◽  
Geographical Position ◽  
Time Of Year ◽  
Horizontal Portion ◽  
Methods Of Measurement

The photo-chemical action exerted by direct sunlight and by diffuse daylight upon a horizontal portion of the earth’s surface, varies with the time of year and with the latitude of the place, and constitutes an important link in the chain of physical relations which connects the organic with the inorganic world. In former communications made to the Royal Society we have endeavoured experimentally to determine the distribution of these chemical actions on the earth’s surface, as varying with the time of day and year, and with the geographical position of the place, when the sky is perfectly unclouded. The methods of measurement there adopted are, unfortunately, not applicable to the determination of the variations in photo-chemical intensity when, as is most frequently the case, the transparency of the atmosphere is more or less obscured by clouds, mist, or rain. To enable us to estimate the alterations which occur in the amount of the chemically active rays falling on the earth’s surface, we must, therefore, have recourse to a mode of measurement totally different from that employed in our former investigations.

Direct micromethod for colorimetry of serum ornithine carbamoyltransferase activity, with use of a linear standard curve.

1978 ◽  
Vol 24 (1) ◽  
pp. 101-107 ◽  
Author(s):  
A A Vassef
Keyword(s):  
Enzyme Activity ◽  
Liver Diseases ◽  
Ornithine Carbamoyltransferase ◽  
Direct Sunlight ◽  
Serum Enzyme ◽  
Standard Curve ◽  
Color Reagent ◽  
Butanedione Monoxime ◽  
Room Lighting

Abstract Determination of serum ornithine carbamoyltransferase (EC 2.1.3.3) activity can be a valuable diagnostic tool in the detection of liver diseases involving cytolytic processes. I describe a micromethod for measuring this activity in serum, in which the reaction product, citrulline, is measured colorimetrically in the incubation mixture without prior deproteinization. To eliminate the interference of serum protein precipitation, the concentration of sulfuric acid in the color reagent has been decreased, without substantial loss of sensitivity. Optimizing the conditions of citrulline determination, in which antipyrine and 2,3-butanedione monoxime are used, has resulted in a linear standard curve. The color formed by citrulline is found to be stable in room lighting and sensitive only to direct sunlight. The precision of the method is inversely correlated to serum enzyme activity, the CV varying between 4.6 and 21.1%.

Lighting controls in areas with innovative daylighting systems: a study of sensor type

2001 ◽  
Vol 33 (1) ◽  
pp. 59-73 ◽  
Author(s):  
Paul J Littlefair ◽  
Abdul Motin
Keyword(s):  
Control Performance ◽  
Direct Sunlight ◽  
Building Research ◽  
Window Systems ◽  
Venetian Blinds ◽  
Horizontal Working ◽  
Clear Glass ◽  
Stable Performance ◽  
Sky Conditions

Innovative daylighting systems often work by redirecting light from the sky and sun onto the ceiling from where it is diffused to light the space. This can cause problems for ceiling mounted photoelectric control sensors. The performances of three types of ceiling sensor were studied in the Building Research Establishment’s mock-up rooms. The window systems included venetian blinds, prismatic film and a light shelf as well as ordinary clear glass. A completely unshielded sensor gave surprisingly stable performance compared with horizontal working plane illuminance. The main exception to this was when direct sunlight reached the sensor itself. Unfortunately the ratio of sensor illuminance to horizontal illuminance was significantly greater under sunny skies than under overcast skies. This could lead to uneven control performance under different sky conditions. An alternative sensor shielded by a darkened tube was also tested. This proved to be very susceptible to the location of patches of sunlight in the space. In a real room it could also be affected by the positions and reflectances of furniture and even occupants. A possible compromise is the use of a partially shielded sensor. This can receive light from all directions except the window. Care is needed in aligning the shield correctly during installation.

Galactic orbits of stars

1966 ◽  
Vol 25 ◽  
pp. 93-97
Author(s):  
Richard Woolley
Keyword(s):  
Globular Cluster ◽  
Potential Field ◽  
High Velocity ◽  
Velocity Vector ◽  
Variable Stars ◽  
The Sun ◽  
Proper Motions ◽  
Rr Lyrae ◽  
The Galaxy

It is now possible to determine proper motions of high-velocity objects in such a way as to obtain with some accuracy the velocity vector relevant to the Sun. If a potential field of the Galaxy is assumed, one can compute an actual orbit. A determination of the velocity of the globular clusterωCentauri has recently been completed at Greenwich, and it is found that the orbit is strongly retrograde in the Galaxy. Similar calculations may be made, though with less certainty, in the case of RR Lyrae variable stars.

Distance to SN 1987A and the LMC

1999 ◽  
Vol 190 ◽  
pp. 549-554
Author(s):  
Nino Panagia
Keyword(s):  
Angular Size ◽  
Large Magellanic Cloud ◽  
Magellanic Cloud ◽  
Light Curves ◽  
Distance Modulus ◽  
Absolute Size ◽  
Sn 1987A

Using the new reductions of the IUE light curves by Sonneborn et al. (1997) and an extensive set of HST images of SN 1987A we have repeated and improved Panagia et al. (1991) analysis to obtain a better determination of the distance to the supernova. In this way we have derived an absolute size of the ringRabs= (6.23 ± 0.08) x 1017cm and an angular sizeR″ = 808 ± 17 mas, which give a distance to the supernovad(SN1987A) = 51.4 ± 1.2 kpc and a distance modulusm–M(SN1987A) = 18.55 ± 0.05. Allowing for a displacement of SN 1987A position relative to the LMC center, the distance to the barycenter of the Large Magellanic Cloud is also estimated to bed(LMC) = 52.0±1.3 kpc, which corresponds to a distance modulus ofm–M(LMC) = 18.58±0.05.

International determination of the total motion of the pole

1961 ◽  
Vol 13 ◽  
pp. 29-41
Author(s):  
Wm. Markowitz
Keyword(s):  
Secular Motion ◽  
The Future

A symposium on the future of the International Latitude Service (I. L. S.) is to be held in Helsinki in July 1960. My report for the symposium consists of two parts. Part I, denoded (Mk I) was published [1] earlier in 1960 under the title “Latitude and Longitude, and the Secular Motion of the Pole”. Part II is the present paper, denoded (Mk II).

Time and Latitude in South Africa

1972 ◽  
Vol 1 ◽  
pp. 27-38
Author(s):  
J. Hers
Keyword(s):  
South Africa ◽  
Cape Town ◽  
Astronomical Observations ◽  
Royal Observatory ◽  
The Republic ◽  
Astronomical Determination ◽  
Limited Accuracy ◽  
Better Than

In South Africa the modern outlook towards time may be said to have started in 1948. Both the two major observatories, The Royal Observatory in Cape Town and the Union Observatory (now known as the Republic Observatory) in Johannesburg had, of course, been involved in the astronomical determination of time almost from their inception, and the Johannesburg Observatory has been responsible for the official time of South Africa since 1908. However the pendulum clocks then in use could not be relied on to provide an accuracy better than about 1/10 second, which was of the same order as that of the astronomical observations. It is doubtful if much use was made of even this limited accuracy outside the two observatories, and although there may – occasionally have been a demand for more accurate time, it was certainly not voiced.

Large-scale Motion of Solar Filaments

2000 ◽  
Vol 179 ◽  
pp. 205-208
Author(s):  
Pavel Ambrož ◽  
Alfred Schroll
Keyword(s):  
Magnetic Flux ◽  
Proper Motion ◽  
Time Scale ◽  
Large Scale ◽  
Accuracy Of Measurements ◽  
Solar Filaments ◽  
General Movement ◽  
Scale Motion ◽  
Velocity Scatter

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.

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