Rubber and rubber products � Determination of chlorine and bromine content

2020 ◽  
Keyword(s):  
Author(s):  
Yu. Koreneva

The aim of the scientific work was to study the toxicokinetics of Bromine in the body of laying hens under conditions of subchronic administration of sodium bromide diet. The subject of the study was the content of bromine in the organs and tissues of laying hens under conditions of subchronic administration of sodium bromide diet. The experiment was on laying hens. Three experimental and one control groups of animals were formed (n=15). The background indicator of the Bromine content in the compound feed was 2.0 mg/kg of feed. An aqueous solution of sodium bromide was added daily to the feed of the experimental groups for 28 days, and the observation of the poultry was continued for the next 14 days. The poultry of the experimental groups received bromine with feed at a dose of 10.0 mg/kg, II – 50.0 mg/kg, III – 250.0 mg/kg of feed. The selection of organs was under conditions of euthanasia of the poultry, by total exsanguination, during inhalation chloroform anesthesia on days 14, 28 and 42 of the experiment, 5 animals per group. The following research methods were used in the work: clinical (daily examination of the poultry), pathological (dissection and sampling of organs for research), toxicological (determination of Bromine content using X-ray fluorescence analysis), statistical (processing of the results was carried out by methods of variation statistics using the Statistica 6.0 software ( StatSoft Inc., USA)). It was found that bromine is absorbed most intensively in the small intestine: on the 28th day of the experiment, its content exceeded the control in group I by 6.5 times, in group II – 22 times, in III – 201.1 times. The study of the content of bromine in the liver, spleen, heart, and brain of three experimental groups testifies to the "material" accumulation of the element. In addition to the digestive tract, the excretion of bromine from the body of laying hens occurred through the kidneys, and possibly with exhaled air. In group III, on the 28th day, its content in the kidneys was 23.1 times higher than the control indicator, and on the 14th day in the lungs, the excess of the control indicator was 27.4 times. The excess of the element was not excreted from the body within 14 days after the cessation of the intake of sodium bromide with food. Key words: Bromine, subchronic intake, laying hens, bromine content in organs, toxicokinetics, sodium bromide.


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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