scholarly journals FRACTIONAL PRECIPITATION OF CELLULOSE NITRATE

1955 ◽  
Vol 11 (1) ◽  
pp. 32-38
Author(s):  
Hiroshi Asaoka ◽  
Akira Suzuki
Keyword(s):  
Cellulose Nitrate ◽  
Fractional Precipitation

Cellulose Nitrate.

1958 ◽  
Vol 14 (3_4) ◽  
pp. 276-276
Author(s):  
G. V. Schulz
Keyword(s):  
Cellulose Nitrate

Application of free-flow electrophoresis to the purification of trichosanthin from a crude product of acetone fractional precipitation

1998 ◽  
Vol 19 (7) ◽  
pp. 1097-1103 ◽  
Author(s):  
Jin-Fang Song ◽  
Tao Liu ◽  
Xin Shen ◽  
Gao-de Wu ◽  
Qi-chang Xia
Keyword(s):  
Free Flow ◽  
Fractional Precipitation ◽  
Crude Product

scholarly journals Thermoresponsive Drug Delivery Using Liquid Crystal-Embedded Cellulose Nitrate Membranes

Drug Delivery ◽  
2006 ◽  
Vol 13 (5) ◽  
pp. 345-350 ◽  
Author(s):  
Rassoul Dinarvand ◽  
Elham Khodaverdi ◽  
Fatemeh Atyabi ◽  
Mohammad Erfan
Keyword(s):  
Drug Delivery ◽  
Liquid Crystal ◽  
Cellulose Nitrate

Mechanisms of deterioration in cellulose nitrate base archival cinematograph film

1990 ◽  
Vol 26 (6) ◽  
pp. 623-630 ◽  
Author(s):  
M. Edge ◽  
N.S. Allen ◽  
M. Hayes ◽  
P.N.K. Riley ◽  
C.V. Horie ◽  
...  
Keyword(s):  
Cellulose Nitrate

scholarly journals Testing the Effectiveness of Protocols for Removal of Common Conservation Treatments for Radiocarbon Dating

Radiocarbon ◽  
2017 ◽  
Vol 60 (1) ◽  
pp. 35-50 ◽  
Author(s):  
Fiona Brock ◽  
Michael Dee ◽  
Andrew Hughes ◽  
Christophe Snoeck ◽  
Richard Staff ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Vinyl Acetate ◽  
Radiocarbon Dating ◽  
Cellulose Nitrate ◽  
Acid Base ◽  
Acrylic Polymers ◽  
Archaeological Wood ◽  
Conservation Treatment ◽  
Chemical Pretreatments ◽  
Selection Of

AbstractTo achieve a reliable radiocarbon (14C) date for an object, any contamination that may be of a different age must be removed prior to dating. Samples that have been conserved with treatments such as adhesives, varnishes or consolidants can pose a particular challenge to 14C dating. At the Oxford Radiocarbon Accelerator Unit (ORAU), common examples of such substances encountered include shellac, the acrylic polymers Paraloid B-67 and B-72, and vinyl acetate-derived polymers (e.g. PVA). Here, a non-carbon-containing absorbent substrate called Chromosorb® was deliberately contaminated with a range of varieties or brands of these conservation treatments, as well as two cellulose nitrate lacquers. A selection of chemical pretreatments was tested for their efficiency at removing them. While the varieties of shellac and Paraloid tested were completely removed with some treatments (water/methanol and acetone/methanol/chloroform sequential washes, respectively), no method was found that was capable of completely removing any of the vinyl acetate-derived materials or the cellulose nitrate lacquers. While Chromosorb is not an exact analog of archaeological wood or bone, for example, this study suggests that it may be possible to remove aged shellac and Paraloid from archaeological specimens with standard organic solvent-acid-base-acid pretreatments, but it may be significantly more difficult to remove vinyl acetate-derived polymers and cellulose nitrate lacquers sufficiently to provide reliable 14C dates. The four categories of conservation treatment studied demonstrate characteristic FTIR spectra, while highlighting subtle chemical and molecular differences between different varieties of shellac, Paraloid and cellulose nitrate lacquers, and significant differences between the vinyl acetate derivatives.

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