Determination of polypropylene glycol extracted from polymers into food-simulating solvents

1978 ◽  
Vol 50 (9) ◽  
pp. 1325-1327 ◽  
Author(s):  
Tore. Ramstad ◽  
T. J. Nestrick ◽  
R. H. Stehl
Keyword(s):  
Polypropylene Glycol

scholarly journals The Determination of Menthol in Tobacco, in Filters and in the Smoke of Mentholated Cigarettes/Untersuchungen über die Verteilung des Menthols auf Tabak, Filter und Rauch von Mentholcigaretten

1972 ◽  
Vol 6 (3) ◽  
Author(s):  
M. Brozinski ◽  
U. Dölberg ◽  
G. Lipp
Keyword(s):  
Gas Chromatography ◽  
Cellulose Acetate ◽  
Steam Distillation ◽  
Internal Standard ◽  
Polypropylene Glycol ◽  
Analytical Results ◽  
Before And After ◽  
Selective Retention ◽  
Different Origin

AbstractA method for the determination of menthol in tobacco, in filters before and after smoking as well as in the smoke of mentholated cigarettes is presented which is based on the combination of steam distillation and liquid-Iiquid partition followed by gas chromatography on polypropylene glycol in the presence of benzylpropionate as an internal standard. The procedure also permits menthone to be quantitatively determined as a characteristic constituent of peppermint oils. Analytical results concerning reproducibility, recovery and sensitivity of the method are detailed. The transfer of menthol from the tobacco rod to the acetate filter and vice versa as a function of the storing period of mentholated cigarettes has been investigated as well as the menthol distribution due to the smoking process. A considerable selective retention of menthol by cellulose acetate filters could be demonstrated. Various mentholated cigarettes of different origin and of different menthol contents have comparatively been analysed.

scholarly journals Experimental Procedure for the Determination of the Critical Coalescence Concentration (CCC) of Simple Frothers

Minerals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 617
Author(s):  
Onur Guven ◽  
Khandjamts Batjargal ◽  
Orhan Ozdemir ◽  
Stoyan I. Karakashev ◽  
Nikolay A. Grozev ◽  
...  
Keyword(s):  
Surface Activity ◽  
Bubble Column ◽  
Triethylene Glycol ◽  
Polypropylene Glycol ◽  
Methyl Isobutyl ◽  
Adsorption Models ◽  
Experimental Procedure ◽  
Air Water Interface ◽  
Surface Tension Isotherms

In this study, the critical coalescence concentrations (CCC) of selected commercial frother solutions, namely polypropylene glycols (PPG 200, 400, and 600), tri propylene glycol (BTPG), triethylene glycol (BTEG), dipropylene glycol (BDPG), and as a reference, methyl isobutyl carbinol (MIBC), were determined using a bubble column based on light absorption. The results for all seven frothers showed that BTEG has the worst bubble inhibiting performance, and PPG 600 has the best bubble inhibiting performance. While critical coalescence concentration (CCC) was found as 3 ppm for PPG 600, it increased to 25 ppm for BTEG. In the case of MIBC, which was the reference point, the CCC value was found as 10 ppm, which was consistent with the literature. The surface tension isotherms of the frothers were determined and analyzed with one of the latest adsorption models. The results indicated that the polypropylene glycol frothers showed more surface activity compared to alcohol or other frothers investigated. This is due to the additional reorganization of the PPG molecules on the air/water interface, thus boosting its surface activity.

scholarly journals Safety Assessment of Alkyl PEG/PPG Ethers as Used in Cosmetics

2016 ◽  
Vol 35 (1_suppl) ◽  
pp. 60S-89S ◽  
Author(s):  
Monice M. Fiume ◽  
Bart Heldreth ◽  
Wilma F. Bergfeld ◽  
Donald V. Belsito ◽  
Ronald A. Hill ◽  
...  
Keyword(s):  
Polyethylene Glycol ◽  
Safety Assessment ◽  
Expert Panel ◽  
Polypropylene Glycol ◽  
Glycol Ethers ◽  
Physiochemical Properties ◽  
Surfactant Properties ◽  
Repeat Units ◽  
Fine Tune

The Cosmetic Ingredient Review (CIR) Expert Panel assessed the safety of 131 alkyl polyethylene glycol (PEG)/polypropylene glycol ethers as used in cosmetics, concluding that these ingredients are safe in the present practices of use and concentration described in this safety assessment when formulated to be nonirritating. Most of the alkyl PEG/PPG ethers included in this review are reported to function in cosmetics as surfactants, skin-conditioning agents, and/or emulsifying agents. The alkyl PEG/PPG ethers share very similar physiochemical properties as the alkyl PEG ethers, which were reviewed previously by the CIR Expert Panel and found safe when formulated to be nonirritating. The alkyl PEG ethers differ by the inclusion of PPG repeat units, which are used to fine-tune the surfactant properties of this group. The Panel relied heavily on data on analogous ingredients, extracted from the alkyl PEG ethers and PPG reports, when making its determination of safety.

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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