Determination of Gaseous and Particulate Fluorides in the Atmosphere (Separation and Collection with a Double Paper Tape Sampler)

2017 ◽  
pp. 352-356
Author(s):  
James P. Lodge
Keyword(s):  
1974 ◽  
Vol 46 (3) ◽  
pp. 410-415 ◽  
Author(s):  
D. F. S. Natusch ◽  
J. R. Sewell ◽  
R. L. Tanner
Keyword(s):  

2012 ◽  
Vol 538-541 ◽  
pp. 2181-2183
Author(s):  
Bao Shan He ◽  
Fang Wei ◽  
Na Gao ◽  
Qi Yu Lu

A test paper tape on the determination of nitrite in food was designed, which is based on the diazotization of nitrite with sulfanilic acid under weakly acidic conditions then coupled with N-(1-Naphthyl)-ethylenediamine dihydrochloride in forming the colour-producing response. Then the reaction membrane turned to purple-red. The deeper purple-red film was obtained in an increased nitrite concentration-dependent manner. Experimental results showed that nitrite concentrations were proportional to a values of the L a b color system. A favorable linearity was presented in the range of 25 to 5000 μg/mL. The correlation coefficient(r) was 0.984 and the whole testing time needed was about 1.5 min at room temperature.


1997 ◽  
Vol 70 (2) ◽  
pp. 124-131
Author(s):  
Nobuo NAKAINO ◽  
Kunio NAGASHIMA
Keyword(s):  

1966 ◽  
Vol 25 ◽  
pp. 93-97
Author(s):  
Richard Woolley

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.


1999 ◽  
Vol 190 ◽  
pp. 549-554
Author(s):  
Nino Panagia

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.


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

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).


1972 ◽  
Vol 1 ◽  
pp. 27-38
Author(s):  
J. Hers

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.


2000 ◽  
Vol 179 ◽  
pp. 205-208
Author(s):  
Pavel Ambrož ◽  
Alfred Schroll

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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