THE DENSITY OF CARBON DIOXIDE

1931 ◽  
Vol 4 (3) ◽  
pp. 283-298 ◽  
Author(s):  
D. LeB. Cooper ◽  
O. Maass

The work published in a previous communication has been extended and revised. Determinations of the density of carbon dioxide are shown for five temperatures from − 30° to + 77 °C., and over a pressure range of 760 to 250 mm. of mercury. The extrapolation of these curves to zero pressure shows a mean value for the atomic weight of carbon = 12.004 ± 0.003. A graph is included which shows the apparent molecular weight as a function of the temperature; molecular volumes have been calculated from this.The results give P.V.T. values for CO2 in the above temperature and pressure range, with an accuracy considered to be greater than available data.

1930 ◽  
Vol 2 (6) ◽  
pp. 388-395 ◽  
Author(s):  
D. LeB. Cooper ◽  
O. Maass

Modifications are described by the Maass and Russel method for the determination of the densitites of gases which permit an accuracy of about one part in 10,000. The determination has been made of the density of carbon dioxide at two temperatures and over a pressure range of 75 to 25 cm. of mercury. The mean value obtained for the molecular weight of carbon dioxide at zero pressure is 44.0033 ± 0.002, from which the atomic weight of carbon is found to be 12.0033 ± 0.002.


2013 ◽  
Vol 19 (3) ◽  
pp. 389-398 ◽  
Author(s):  
Hadi Baseri ◽  
Ali Haghighi-Asl ◽  
Nader Lotfollahi

In this paper, Peng Robinson equation of state is used for thermodynamic modeling of the solubility of various solid components in the supercritical carbon dioxide. Moreover, the effects of three mixing rules of Van der Waals mixing rules, Panagiotopoulos and Reid mixing rules and modified Kwak and Mansoori mixing rules on the accuracy of calculation results were studied. Good correlations between calculated and experimental data were obtained in the wide temperature and pressure range. A comparison between used models shows that modified Kwak and Mansoori mixing rules give better correlations in comparison with the other mixing rules.


1990 ◽  
Vol 63 (03) ◽  
pp. 499-504 ◽  
Author(s):  
A Electricwala ◽  
L Irons ◽  
R Wait ◽  
R J G Carr ◽  
R J Ling ◽  
...  

SummaryPhysico-chemical properties of recombinant desulphatohirudin expressed in yeast (CIBA GEIGY code No. CGP 39393) were reinvestigated. As previously reported for natural hirudin, the recombinant molecule exhibited abnormal behaviour by gel filtration with an apparent molecular weight greater than that based on the primary structure. However, molecular weight estimation by SDS gel electrophoresis, FAB-mass spectrometry and Photon Correlation Spectroscopy were in agreement with the theoretical molecular weight, with little suggestion of dimer or aggregate formation. Circular dichroism studies of the recombinant molecule show similar spectra at different pH values but are markedly different from that reported by Konno et al. (13) for a natural hirudin-variant. Our CD studies indicate the presence of about 60% beta sheet and the absence of alpha helix in the secondary structure of recombinant hirudin, in agreement with the conformation determined by NMR studies (17)


1975 ◽  
Vol 33 (03) ◽  
pp. 553-563 ◽  
Author(s):  
B Østerud ◽  
K Laake ◽  
H Prydz

SummaryThe activation of factor IX purified from human plasma has been studied. Factor XIa and kallikrein separately activated factor IX to factor IXa. In both cases factor IX a had an apparent molecular weight of about 42–45000 in sodium dodecyl sul-phate-polyacrylamide disc gel electrophoresis compared with a molecular weight of about 70000 for the native factor IX. The activation by XIa required Ca2+-ions whereas Ca2+-ions did not influence the activation by kallikrein. A mixture of tissue thromboplastin and factor VII or RusselPs-viper venom alone did not activate factor IX. Trypsin activated and plasmin inactivated factor IX.


1977 ◽  
Vol 72 (1) ◽  
pp. 194-208 ◽  
Author(s):  
L D Hodge ◽  
P Mancini ◽  
F M Davis ◽  
P Heywood

A subnuclear fraction has been isolated from HeLa S3 nuclei after treatment with high salt buffer, deoxyribonuclease, and dithiothreitol. This fraction retains the approximate size and shape of nuclei and resembles the nuclear matrix recently isolated from rat liver nuclei. Ultrastructural and biochemical analyses indicate that this structure consists of nonmembranous elements as well as some membranous elements. Its chemical composition is 87% protein, 12% phospholipid, 1% DNA, and 0.1% RNA by weight. The protein constituents are resolved in SDS-polyacrylamide slab gels into 30-35 distinguishable bands in the apparent molecular weight range of 14,000 - 200,000 with major peptides at 14,000 - 18,000 and 45,000 - 75,000. Analysis of newly synthesized polypeptides by cylindrical gel electrophoresis reveals another cluster in the 90,000-130,000 molecular weight range. Infection with adenovirus results in an altered polypeptide profile. Additional polypeptides with apparent molecular weights of 21,000, 23,000, and 92,000 become major components by 22 h after infection. Concomitantly, some peptides in the 45,000-75,000 mol wt range become less prominent. In synchronized cells the relative staining capacity of the six bands in the 45,000-75,000 mol wt range changes during the cell cycle. Synthesis of at least some matrix polypeptides occures in all phases of the cell cycle, although there is decreased synthesis in late S/G2. In the absence of protein synthesis after cell division, at least some polypeptides in the 45,000-75,000 mol wt range survive nuclear dispersal and subsequent reformation during mitosis. The possible significance of this subnuclear structure with regard to structure-function relationships within the nucleus during virus replication and during the life cycle of the cell is discussed.


1988 ◽  
Vol 152 (1-2) ◽  
pp. 171-174 ◽  
Author(s):  
Yoshihiro Nakata ◽  
Chie Hiraoka ◽  
Tomio Segawa

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