Determination of the acidity of catalysts by thermoadsorption with a cyclic temperature program

1980 ◽  
Vol 13 (3) ◽  
pp. 263-268 ◽  
Author(s):  
J. Stoch ◽  
A. Szczęsna
Keyword(s):  
Temperature Program ◽  
Cyclic Temperature

Determination of diffusion coefficients with a general temperature program using dta equipment

1983 ◽  
Vol 64 (1-2) ◽  
pp. 229-236 ◽  
Author(s):  
P. Kubíček ◽  
B. Wozniaková ◽  
J. Leško
Keyword(s):  
Diffusion Coefficients ◽  
Temperature Program

scholarly journals Determination of Free Fatty Acids in Sausage Meat

2010 ◽  
Vol 67 (2) ◽  
Author(s):  
Codrean POP ◽  
Levente BARA ◽  
Elena HORJ ◽  
Andreea IORDACHE ◽  
Cornel LASLO ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Mass Spectra ◽  
Methyl Esters ◽  
Extraction Procedure ◽  
Internal Standard ◽  
Quadrupole Mass ◽  
Temperature Program ◽  
Separation Temperature

The aim of this work was to establish the extraction procedure, the derivatization method, the separation temperature program, the identification and quantitation of the free fatty acids from meat. A gas chromatography - mass spectrometric (GC/MS) technique was used. The fatty acids were obtained by grounding meat, water and sand and then extraction was performed by mixing chloroform:methanol (2:1) during 30 seconds, at room temperature. The fatty acids were derivatized to obtain methyl esters. A Trace DSQ ThermoFinnigan quadrupole mass spectrometer coupled with a Trace GC was used. Fatty acids were separated on a Rtx-5MS capillary column, 30m x 0.25mm, 0.25µm film thickness, using a suitable temperature program. The identification of fatty acids was obtained by comparison of fatty acids methyl esters (FAME) mass spectra with the mass spectra of FAME kits and of NIST library. Concentrations of fatty acids were calculated by using a proper internal standard.

A General Analysis of Phase-Change Energy Storage for Solar Energy Applications

1992 ◽  
Vol 114 (4) ◽  
pp. 203-211 ◽  
Author(s):  
C. K. Hsieh ◽  
Chang-Yong Choi
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Numerical Solution ◽  
Test Results ◽  
Unified Approach ◽  
Interface Position ◽  
Energy Applications ◽  
Three Phase ◽  
Cyclic Temperature

A unified approach is developed for the analysis of one, two, or three-phase melting or solidification of a semi-infinite medium with or without subcooling or superheating and imposed with constant, monotonic, or cyclic temperature or flux conditions. A source and sink method is presented in which a sink front is used to characterize a melt front while a source front is used to characterize a freeze front. An integrodifferential equation is then derived for the interface position which is linearized locally for numerical solution. This position is, in turn, used as input for the determination of the temperature distribution and energy storage and release in different phases of the medium. The numerical solution presented in this paper has shown to be unique, convergent, stable, and accurate. The analysis has been applied to the study of phase change in a subcooled paraffin wax imposed with a cyclic temperature condition. Test results yield some interesting phenomena related to the merging of phase-change fronts and hysteresis of energy storage and release, among others, which have not previously been reported in the literature. Their relations to the energy storage and release are particularly stressed in the paper.

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.

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