Polyurethane foam sorbents in separation science

Polyurethane Foam Sorbents in Separation Science

Volumn , Issue , 2018, Pages 1-219

  Braun, Tibor ^a   Navratil, James D ^b   Farag, A B ^c  

^a EÖTVÖS LORÁND UNIVERSITY   (Hungary)

^b Rockwell International   (United States)

^c Mansoura University   (Egypt)

Author keywords

[No Author keywords available]

Indexed keywords

REVIEWS; RIGID FOAMED PLASTICS;

OPEN PORES; POLYMERIC SORBENTS; POLYURETHANE FOAM; SEPARATION SCIENCE;

POLYURETHANES;

EID: 85051620836     PISSN: None     EISSN: None     Source Type: Book    
DOI: 10.1201/9781351075916     Document Type: Book

References (270)

1. Braun, T. and Farag, A. B., Cellular and foamed plastics as separation media. A new geometrical form of the solid phase in analytical liquid-solid contact, Talanta, 22, 699, 1975.
2. Flinn, J. E. and Cherry, R. H., Jr., Separation processes based on spherical membrane systems, Chem. Eng. Progr. Symp. Ser., 65, 90, 1969.
3. Braun, T. and Farag, A. B., Polyurethane foams and microspheres in analytical chemistry. Improved liquid-solid, gas-solid and liquid-liquid contact via a new geometry of the solid-phase, Anal. Chim. Acta, 99, 1, 1978.
4. Brunschwig, H., Liber de Arte Distillandi, 1512. (See also Bittel, A., Dissertation, Tubingen, 1957.)
5. Bayer, E., Gaschromatographie, 2nd ed., Springer-Verlag, Heidleberg, 1962, p. 4.
6. Lai, D., Arnold, J. R., and Somayajulu, B. L. K., Method for the extraction of trace elements from sea water, Ceochim. Cosmochim. Acta, 28, 1111, 1964.
7. Bauman, E. K., Goodson, L. H., Guilbault, G. G., and Kramer, D. N., Preparation of immobilized cholinesterase for use in analytical chemistry, Anal. Chem., 37, 1378, 1965.
8. Van Venrooy, J. J., Polymeric foam column packaging for gas chromatography, U.S. Patent 3,347,020, 1967.
9. Bowen, H. J. M., Absorption by polyurethane foams; new method of separation, J. Chem. Soc. A, 1082, 1970;
10. Braun, T. and Farag, A. B., Reversed-phase foamchromatography. Separation of palladium, bismuth and nickel in the tributyl-phosphate-thiourea-perchloric acid system, Anal. Chim. Acta, 61, 265, 1972.
11. Gesser, H. D., Chow, A., Davis, F. C, Uthe, J. F., and Reinke, J., The extraction and recovery of polychlorinated biphenyls (PCB) using porous polyurethane foam, Anal. Lett. A, 883, 1971.
12. Braun, T. and Farag, A. B., Foam chromatography. Solid foams as supports in column chromatography, Talanta, 19, 828, 1972.
13. Bowen, H. J. M., Recovery of substances from a fluid medium, British Patent 1,305,375, 1973.
14. Schiller, P. and Cook, G. B., Determination of trace amounts of gold in natural sweet waters by nondestructive activation analysis after preconcentration, Anal. Chim. Acta, 54, 364, 1971.
15. Sukiman, S., The extraction of gold from aqueous solution with treated and untreated polyurethane foam, Radiochem. Radioanal. Lett., 18, 129, 1974.
16. Te-Shang Lo, Liu Chou, Chien-Chun Tu, Hsin-Liu Liu, and Ming Li, Plastic foam adsorption and thiourea desorption in atomic absorption determination of gold, Fen Hsi Hua Hsuch, 8, 77, 1980;
17. Chem. Abstr., 94, 40790e, 1981.
18. Gesser, H. D., Bock, E., Baldwin, W. G., Chow, A., McBride, D. W., and Lipruski, W., Open-cell polyurethanefoam sponge as a “solvent extractor” for gallium and iron, Sep. Sci., 11, 315, 1976.
19. Gesser, H. D. and Horsfall, G. A., Separation and concentration of gallium by polyurethane, J. Chim. Phys.,14, 1072, 1977.
20. Gesser, H. D., Horsfall, G. A., Gough, K. M., and Krawchuk, B., Transport of metal complex chlorides through plastic film membrane, Nature (London), 268, 323, 1977.
21. Oren, J. J., Gough, K. M., and Gesser, H. D., The solvent extraction of iron (III) from acidic chloride solutions by open cell polyurethane foam sponge (OCPUFS), Can. J. Chem., 57, 2032, 1979.
22. Lo, V. S. K. and Chow, A., The extraction of antimony with open-cell polyurethane foam, Anal. Chim. Acta, 106, 161, 1979.
23. Lo, V. S. K. and Chow, A., Extraction of tin by the use of polyurethane foam, Talanta, 28, 157, 1981.
24. Gesser, H. D. and Gupta, B. M., The extraction of uranyl nitrate from aqueous nitrate solutions by open-cell polyurethane foam sponge (OCPUFS), Paper 80-122, Proc. I.S.E.C. Conf., Grenoble, 1980.
25. Korkisch, J., Steffan, I., and Navratil, J. D., Recovery of uranium with polyurethane foam, in Actinide Recovery From Waste and Low Grade Sources, Navratil, J. D. and Schulz, W. W. (Eds.), Harwood Academic Publishers, New York, 1982, 349.
26. Braun, T., Farag, A. B., and Maloney, M. P., Polyurethane-pyridylazonaphthol foamsin the preconcentration and separation of trace elements, Anal. Chim. Acta, 93, 191, 1977.
27. Braun, T. and Farag, A. B., Polyurethane foam of the polyether type as a solid polymeric extractant for cobalt and iron from thiocyanate media, Anal. Chim. Acta, 98, 133, 1978.
28. Chow, A., Yamashita, G. T., and Hamon, R. F., X-ray fluorescence determination of cobalt on polyurethane foam, Talanta, 28, 437, 1981.
29. Hamon, R. F., Khan, A. S., and Chow, A., The cation-chelation mechanism of metal-ion sorption by polyurethanes, Talanta, 29, 313, 1982.
30. Hamon, R. F. and Chow, A., Extraction of cobalt by polyurethane foam, Abstr. 60th C.I.C. Conf., Chem. Institute of Canada, Montreal, 1977.
31. Al-Bazi, S. J. and Chow, A., Extraction of rhodium and iridium with polyurethane foam, Anal. Chem., 53, 1073, 1981.
32. Braun, T. and Abbas, M. N., Unloaded polyurethane foams as solid extractants for some metal thiocyanate complexes from aqueous solution, Anal. Chim. Acta, 134, 321, 1982.
33. Braun, T., Abbas, M. N., Elek, A., and Bakos, L., Reagent-loaded andunloaded polyurethane foam as a preconcentration matrix in neutron activation analysis, J. Radioanal. Chem., 67, 359, 1981.
34. Al-Bazi, S. J. and Chow, A., Extraction of palladium thiocyanate with polyurethane foam, Talanta, 29, 507, 1982.
35. Al-Bazi, S. J. and Chow, A., Mechanism of the extraction of palladium(II) thiocyanate complex by polyether foam, Talanta, 30, 487, 1983.
36. Hamon, R. F., Extraction of cobalt by polyurethane foam, Ph.D. thesis, University of Manitoba, 1981.
37. Maloney, M. P., Moody, G. J., and Thomas, J. D. R., Extraction of metals from aqueous solution with polyurethane foam, Analyst, 105, 1087, 1980.
38. Moody, G. J., Thomas, J. D. R., and Yarmo, M. A., Mechanism of metal sorption from aqueous potassium thiocyanate by polyether type polyurethane foam, Anal. Proc, 20, 132, 1983.
39. Ibrahim, S. A., M.Sc. thesis, Mansoura University, 1983.
40. Abbas, M. N., Vertes, A. and Braun, T., Mössbauer study of the sorption of ferric ions from thiocyanate media by polyether and polyester type polyurethane foams, Radiochem. Radioanal. Lett., 54, 17, 1982.
41. Bowen, H. J. M., Testing the recovery of silver and gold from liquid mineral wastes, Radiochem. Radioanal. Lett., 7, 71, 1971.
42. Braun, T. and Farag, A. B., The recovery of gold from alkaline cyanide media with a polyurethane foam sorbent, Anal. Chim. Acta, 153, 319, 1983.
43. Braun, T. and Farag, A. B., The recovery of gold from thiourea solutions with open-cell polyurethane foams, Anal. Chim. Acta, 66, 419, 1973.
44. Khan, A. S., Baldwin, W. G., and Chow, A., The extraction of alkali metal picrates by polyurethane foam using crown ether, Can. J. Chem., 59, 1490, 1981.
45. Khan, A. S., Baldwin, W. G., and Chow, A., Extraction of monovalent and divalent cations by polyether-based polyurethane foam, Anal. Chim. Acta, 146, 201, 1983.
46. Khan, A. S. and Chow, A., Studies on the extraction of phosphomolybdate by polyether foam, Talanta, 30, 173, 1983.
47. Moore, R. A. and Chow, A., The extraction of iridium and platinum from organic solvents by polyurethane foams, Talanta, 27, 315, 1980.
48. Bedford, J. W., The use of polyurethane foam plugs for extraction of polychlorinated biphenyls (PCB’s) from natural waters, Bull. Environ. Contam. Toxicol., 12, 622, 1974.
49. Uthe, J. F., Reinke, J., and O’Borodvich, H., Field studies on use of coated porous polyurethane plugs as indwelling monitors of organochlorine pesticides and polychlorinated biphenyl contents of streams, Environ. Lett., 6, 103, 1974.
50. Bidleman, T. F. and Olney, C. E., Chlorinated hydrocarbons in the Sargasso Sea atmosphere and surface water, Science, 183, 516, 1974.
51. Musty, P. R. and Nickless, G., The extraction and recovery of chlorinated insecticides and polychlorinated biphenyls from water using porous polyurethane foams, J. Chromatogr., 100, 83, 1974.
52. Musty, P. R. and Nickless, G., Foams as extractants for organochlorine insecticides, polychlorobi-phenyls and heavy metals from water, Proc. Anal. Div. Chem. Soc, 12, 295, 1975.
53. Musty, P. R. and Nickless, G., Extractants for organochlorine insecticides and polychlorinated biphenyls from water, J. Chromatogr., 120, 369, 1976.
54. Murphy, T. J. and Rzeszutko, Ch.P., Precipitation inputs of PCBs to Lake Michigan, J. Great Lakes Res., 3, 305, 1977.
55. Chau, A. S. Y. and Babjak, L. J., Column chromatographic determination of Mirex, photomirex and polychlorinated biphenyls in lake-sediments, J. Assoc. Off. Anal. Chem., 62, 107, 1979.
56. Babjak, L. J. and Chau, A. S. Y., Evaluation of fourteen charcoal-polyurethane foam mixtures for the separation of Mirex and photomirex from Aroclor -1254, J. Assoc. Off. Anal. Chem., 62, 1174, 1979.
57. Smith, S. R., Tanaka, J., Futoma, T. J., and Smith, T. E., Sampling and preconcentration methods for the analysis of polycyclic aromatic hydrocarbons in water systems, CRC Crit. Rev. Anal. Chem., 10, 375, 1981.
58. Saxena, J., Kozuchowski, J., and Basu, D. K., Monitoring of polynuclear aromatic hydrocarbons in water. I. Extraction and recovery of benzo(a)pyrene with porous polyurethane foam, Environ. Sci. Technol., II, 682, 1977.
59. Basu, D. K. and Saxena, J., Monitoring of polynuclear aromatic hydrocarbons in water. II. Extraction and recovery of six representative compounds with polyurethane foams, Environ. Sci. Technol., 12, 791, 1978.
60. Basu, D. K. and Saxena, J., Polynuclear aromatic hydrocarbons in selected U.S. drinking waters and their raw water sources, Environ. Sci. Technol., 12, 795, 1978.
61. Tanaka, T., Hiiro, K., and Kawahara, A., A simple method for the determination of alkylbenzene-sulfonate by visual colorimetry, Bunseki Kagaku (Japan Analyst), 22, 523, 1973.
62. Gough, K. M. and Gesser, H. D., The extraction and recovery of phtalate esters from water using porous polyurethane foam, J. Chromatogr., 115, 383, 1975.
63. Braun, T. and Farag, A. B., Pulsed column, redox techniques using flexible foam fillings, Anal. Chim. Acta, 65, 139, 1973.
64. Braun, T. and Palágyi, S., Pulsating column separations with a polyurethane foam syringe, Anal. Chem., 51, 1697, 1979.
65. Denton, M. S. and Dinsmore, S. R., A comparison of synthetic adsorbents, including open-pore polyurethane, as applied to coal conversion process aqueous effluent cleanup, presented 2nd Chem. Congr. N. Am. Continent, American Chemical Society, Las Vegas, Nevada, August 24-29, 1980.
66. Gesser, H. D., Sparling, A. B., Chow, A., and Turner, C. W., The monitoring of organic matter with polyurethane foam, J. Am. Water Works Assoc., 65, 220, 1973.
67. Schlicht, R. C. and McCoy, F. C, Selective adsorption of phenols from hydrocarbons solutions using polyurethane foam, US Patent 3,617,531, 1971.
68. Will, R. G. and Grutsch, J. F., Purifying oil-contaminated water by filtration, US Patent 3,617,552, 1971.
69. Adams, J. D. and Caro, J. H., Polyurethane foam as a trapping agent for airborne pesticides, EPA Research Rep. EPA-600/4-80-008, U.S. Environmental Protection Agency, Washington, D.C., 1980.
70. Bidleman, T. F. and Olney, C. E., High-volume collectionof atmospheric polychlorinated biphenyls, Bull. Environ. Contam. Tox., 11, 442, 1974.
71. Oehme, M. and Stray, H., Quantitative determination of ultra-traces of chlorinated compounds in high-volume air samples from the the Arctic using polyurethane foam as collection medium, Z. Anal. Chem., 311, 665, 1982.
72. Lewis, R. G. and Zimmerman, N. J., Anal. Qual. Contr. Newslett., 28, 7, 1976.
73. Rice, C. P., Olney, C. E., and Bidleman, T. F., World Meteorological Organization Special Environmental Report, No. 10, WMO-460, 1977, p. 216.
74. Stratton, C. L., Whitlock, S. A., and Allan, J. M., A method for sampling and analysis of polychlorinated biphenyls (PCB’s) in ambient air, EPA Research Rep. EPA-600/4-78-048, U.S. Environmental Protection Agency, Washington, D.C., 1978.
75. Lewis, R. G., Brown, A. R., and Jackson, M. D., Evaluation of polyurethane foam for sampling of pesticides, polychlorinated biphenyls and polychlorinated naphthalenes in ambient air, Anal. Chem., 49, 1668, 1977.
76. Lewis, R. G., MacLeod, K. E., and Jackson, M. D., Sampling methodologies for airborne pesticides and polychlorinated biphenyls, Paper No. 65, Chemical Congress, Am. Chem. Soc. -Chem. Soc. Japan, Honolulu, Hawaii, April 2-6, 1979.
77. Margeson, J. H., Methodology for measurement of PCBs in ambient air and stationary sources. A Review Environmental Monitoring and Support Lab., Research Triangle Park, N.C., Report PB 269 500, Springfield, Virg., 1977.
78. Stratton, C. L., Witlock, S. A., and Allan, J. M., A method for sampling and analysis of polychlorinated biphenyls (PCBs) in ambient air, EPA Research Rep. EPA600/4-78-048, U.S. Environmental Protection Agency, Washington, D.C., 1978.
79. Turner, B. C. and Glotfelty, D. E., Field air sampling of pesticide vapors with polyurethane foam, Anal. Chem., 49, 7, 1977.
80. Erickson, M. D., Michael, L. C, Zweidinger, R. A., and Pellizzari, E. D., Development of methods for sampling and analysis of polychlorinated naphthalenes in ambient air, Environ. Sci. Technol., 12, 927, 1978.
81. Erickson, M. D., Michael, L. C, Zweidinger, R. A., and Pellizzari, E. D., Sampling and analysis for polychlorinated naphthalenes in environment, J. Assoc. Off. Anal. Chem., 61, 1335, 1978.
82. Erickson, M. D., Zweidinger, R. A., Michael, L. C, and Pellizzari, E. D., Environmental monitoring near industrial sites: polychloronaphthalenes, EPA Research Rep. EPA/560/6-77/019, U.S. Environmental Protection Agency, Washington, D.C., 1977.
83. Turner, B. C, Taylor, A. W., Glotfelty, D. E., and Watson, D. R., Volatization of microencapsulated and conventionally applied chlorpropham in field, Agron. J., 70, 933, 1978.
84. Cliath, M. M., Spencer, W. F., Farmer, W. J., Shoup, T. D., and Grover, R., Volatization of S-ethyl N,N-dipropylthio-carbamate from water and wet soil during and after flood irrigation of an alfalfa field, J. Agr. Food Chem., 28, 610, 1980.
85. Simon, C. G. and Bidleman, T. F., Sampling airborne polychlorinated biphenyls with polyurethane foam. Chromatographic approach to determining retention efficiencies, Anal. Chem., 51, 1110, 1979.
86. Burdick, N. F. and Bidleman, T. F., Frontal movement of hexachlorobenzene and polychlorinated biphenyl vapors through polyurethane foam, Anal. Chem., 53, 1926, 1981.
87. Vannucchi, C. and Berlincioni, M., Sampling and analytical method to determine PCB concentrations in the air of the working areas of an electrical industry, Am. Ind. Hyg. Assoc. J., 41, 352, 1980.
88. Atlas, E. and Griam, C. S., Global transport of organic pollutants ambient concentrations in the remote marine atmosphere, Science, 211, 163, 1981.
89. Billings, W. N. and Bidleman, T. F., Field comparison of polyurethane foam and tenax-GC resin for high-volume air sampling of chlorinated hydrocarbons, Environ. Sci. Technol., 14, 679, 1980.
90. Doskey, P. V. and Andren, A. W., High-volume samplingof airborne polychlorobiphenyls with Amberlite® XAD-2 resin, Anal. Chim. Acta, 110, 129, 1979.
91. Lewis, R. G. and Jackson, M. D., Modification and evaluation of a high-volume air sampler for pesticides and semivolatile industrial organic chemicals, Anal. Chem., 54, 592, 1982.
92. Lewis, R. G. and MacLeod, K. E., Portable sampler for pesticides and semivolatile industrial organic chemicals in air, Anal. Chem., 54, 310, 1982.
93. Oehme, M. and Stray, H., Quantitative determination of ultra-traces of chlorinated compounds in high-volume air samples from the Arctic using polyurethane foam as collection medium, Z. Anal. Chem., 311, 665, 1982.
94. Yamasaki, H., Kuwata, K., and Miyamoto, M., Collection of atmospheric polycyclic aromatic hydrocarbons using polyurethane foam plugs, Bunseki Kagaku, 27, 317, 1978.
95. Yamasaki, H. and Kuwata, K., Collection of atmospheric phthalate esters using polyurethane foam plugs, Bunseki Kagaku, 26, 1, 1977.
96. Thrane, K. E. and Mikalsen, A., High-volume samplingof airborne polycyclic aromatic-hydrocarbons using glass-fiber filters and polyurethane foams, Atmos. Environ., 15, 909, 1981.
97. Giam, C. S., Chan, H. S., Neff, G. S., and Atlas, E. L., Phthalate ester plasticizers. New class of marine pollutant, Science, 199, 419, 1978.
98. Yamasaki, H. and Kuwata, K., Collection of atmospheric phthalate esters using polyurethane foam plugs, Bunseki Kagaku, 26, 1, 1977.
99. Grover, R. and Kerr, L. A., Evaluation of polyurethane foam as a trapping medium for herbicide vapor in air monitoring and worker inhalation studies, J. Environ. Sci. Health, B16, 59, 1981.
100. Strickman, R. L., Tobacco smoke-filtering materials, U.S. Patent 3,618,618, 1971.
101. Moody, G. J. and Thomas, J. D. R., Extractions and separations with foamed plastics and rubbers, Analyst, 104, 1, 1979.
102. Moody, G. J. and Thomas, J. D. R., Chromatographic Separation and Extraction with Foamed Plastics and Rubbers, Marcel Dekker, New York, 1982.
103. Braun, T., Trends in using resilient polyurethane foams as sorbents in analytical chemistry, Z. Anal. Chem., 314, 652, 1983.
104. Bailey, M. E., Polyurethanes. Study in chemical principles, J. Chem. Educ, 48, 809, 1971.
105. Thomas, C. R., The formation of cellular-plastics, Br. Plastics, 552, 1965.
106. Benning, C. J., Plastics Foams: The Physics and Chemistry of Product Performance and Process Technology, Vol. 1. Chemistry and Physics of Foam Formation, John Wiley & Sons, New York, 1969.
107. Cellular Plastics, Proc. Conf., Natick, Massachussetts, 1966, National Academy of Sciences, National Research Council, Washington, D.C., 1967.
108. Ferrigno, T. H., Rigid Plastic Foams, Reinhold, New York, 1963.
109. Hunter, B. A. and Kleinfeld, M. J., Rubber World, 153, 84, 1965.
110. Gross, S., Ed., Modern Plastics Encyclopedia, Vol. 46, McGraw-Hill, New York, 1969, 248.
111. David, D. J. and Staley, H. B., Analytical Chemistry of the Polyurethanes, Vol. 16, Part 3, John Wiley & Sons, New York, 1969.
112. Corish, P. J., Identification and analysis of polyurethane rubbers by infrared spectroscopy, Anal. Chem., 31, 1298, 1959.
113. Murphy, E. B. and O’Neil, W. A., Infrared and dielectric analysis of structural polyurethane foam, Soc. Plas. Eng. J., 18, 191, 1962.
114. Greth, G. G., Smith, R. G., and Rudkin, G. O., The determination and effect of unreacted isocyanate groups in rigid urethane foams, J. Cellular Plastics, 1, 159, 1965.
115. Merten, R., Braun, G., and Lauerer, D., Structure of polyurethane foams, Kunststoffe, 55, 249, 1965.
116. Kuposov, L. I. and Zharkov, V. V., Metod opredelenija vtorichnikh svjazij poliuretanah, Plastic Massy, 63, 1972.
117. Sumi, M., Chokki, Y., Nakai, Y., Nakabayashi, M., and Kanzawa, T., Structure of polyurethane elastomers. I. Nuclear magnetic resonance (NMR) spectra of the model compounds and some linear polyurethanes, Makromol. Chem., IS, 146, 1964.
118. Brame, E. G., Ferguson, R. C, and Thomas, G. J., Identification of polyurethanes by high resolution nuclear magnetic resonance spectrometry, Anal. Chem., 39, 517, 1967.
119. Lieser, K. H., Calmano, W., Heuss, E., and Neitzert, V., Neutron activation as a routine method for determination of trace-elements in water, J. Radioanal. Chem., 37, 717, 1977.
120. Vanderborght, B. and Van Grieken, R., Reduction of trace-metal levels in analytical grade activated carbon, Anal. Chim. Acta, 89, 399, 1977.
121. Bergerioux, C, Blanc, J. P., and Haerdi, W., Preconcentration of environmental trace elements on organic support for neutron activation and high resolution photon spectrometry, J. Radioanal. Chem., 37, 823, 1977.
122. Krämer, H. J. and Neidhart, B., Determination of trace amounts of dissolved mercury compounds by instrumental neutron activation analysis following a selective preconcentration, J. Radioanal. Chem., 37, 835, 1977.
123. Sava, S., Zikovsky, L., and Boisvert, J., Determination of arsenic, cadmium and zinc in river water by neutron activation analysis, J. Radioanal. Chem., 57, 23, 1980.
124. 14C, Radiochem. Radioanal. Lett., 2, 169, 1969.
125. Braun, T. and Farag, A. B., A new method for column packing in reversed-phase chromatography, Anal. Chim. Acta, 62, 476, 1972.
126. Nachtrieb, N. H. and Fryxell, R. E., The extraction of gallium chloride by isopropyl ether, J. Am. Chem. Soc., 71, 4035, 1949.
127. Hertel, G. R. and Clark, H. M., Paramagnetic resonance behavior of tetrachloroferrate ion in isopropyl ether, J. Phys. Chem., 65, 1930, 1961.
128. Furman, N. H., Mundy, R. J., and Morrison, G. H., The distribution of uranyl nitrate from aqueous solutions to diethyl ether, U.S. Atomic Energy Commission Report AECD-2938, 1950.
129. Sotobayashi, T., Suzuki, T., and Tonouchi, S., Liquid-liquid extractionof various metal ions with polyethyleneglycol and its derivatives, Chem. Le H., 585, 1976.
130. Sotobayashi, T., Suzuki, T., and Yamada, K., Liquid-liquid extractionof cobalt(ll) with polyethyleneglycol and its derivatives, Chem. Lett., 77, 1976.
131. Sotobayashi, T., Suzuki, T., and Kudo, H., Liquid-liquid extractionof some actinides with polyethyleneglycol and its derivatives, J. Radioanal. Chem., 36, 145, 1977.
132. Christensen, J. J., Eatough, D. J., and Izatt, R. M., The synthesis and ion-binding of synthetic multidentate macrocyclic-compounds, Chem. Rev., 74, 351, 1974.
133. Yanagida, S., Takahashi, K., and Okahara, M., Metal-ion complexationof noncyclic poly(oxyethylene) derivatives. I. Solvent-extraction of alkali and alkaline-earth metal thiocyanates and iodides, Bull. Chem. Soc. Jap., 50, 1386, 1977.
134. May, P. M., Linder, P. W., and Williams, D. R., Computer simulation of metal-ion equilibria in biofluids: models for low-molecular-weight complex distribution of calcium(ll), magnesium(ll), manganese(II), iron(III), copper(ll), zinc(II) and lead(Il) ions in human-blood plasma, J. Chem. Soc. Dalton Trans., 588, 1977.
135. Lodeishchikov, V. V. and Panchenko, A. F., Sorption of gold from acid solutions of thiourea by activated carbon, Tsvet. Metal., 41, 25, 1968.
136. Pedersen, C. J., Cyclic polyethers and their complexes with metal salts, J. Am. Chem. Soc, 89, 7017, 1967.
137. Pedersen, C. J., Cyclic polyethers and their complexes with metal salts, J. Am. Chem. Soc, 89, 2495, 1967.
138. Izatt, R. M., Eatough, D. J., and Christensen, J. J., Thermodynamics of cation-macrocyclic compound interaction, Struct. Bonding (Berlin), 16, 161, 1973.
139. Bright, D. and Truter, M. R., Crystal-structure ofa cyclic polyether complex of alkali-metal thiocyanate, Nature (London), 225, 176, 1970.
140. 2+ with some organic counter-ions and dicyclohexyl-18-crown-6 as adduct-forming reagent, Talanta, 25, 91, 1978.
141. Jorgensen, C. K., Complexes of the 4d- and 5d-groups. II. Crystal field and electron transfer spectra of ruthenium(II) and (III), iridium(IV) and platinum(IV), Acta Chem. Scand., 10, 518, 1956.
142. Martin, D. S., Jr., Advances in Chemistry, No. 98, American Chemical Society, Washington, D.C., 1971.
143. Armour, J. A. and Burke, J. A., Method for separating polychlorinated biphenyls from DDT and its analogs, J. Assoc. Off. Anal. Chem., Si, 761, 1970.
144. Fehringer, N. V. and Westfall, J. E., Separation and identification of DDT analogs in presence of polychlorinated biphenyl compounds by two-dimensional thin-layer chromatography, Chromatogr., 57, 397, 1971.
145. Hutzinger, O., Safe, S., and Zitko, V., The Chemistry of PCB’s, CRC Press, Buca Raton, Fla., 1974.
146. World Health Organization, Monograph on the Evaluation of Carcinogenic Risk of Chemicals to Man: Certain Polycyclic Aromatic Hydrocarbons and Heterocyclic Compounds, Vol. 3, World Health Organization, Geneva, Switzerland, 1973.
147. Fowler, D. L. and Mahan, J. N., The Pesticide Review, 1977, Agricultural Stabilization and Conservation Service, U.S. Dept. of Agriculture, Washington, D.C., 1978.
148. Yule, W. N., Cole, A. F. W., and Hoffman, I., Survey for atmospheric contamination following forest spraying with fenitrothion, Bull. Environ. Contam. Tox., 6, 289, 1971.
149. Miles, J. W., Fetzer, L. E., and Pearce, G. W., Collection and determination of trace quantities of pesticides in air, Environ. Sci. Technol., 4, 420, 1970.
150. Stanley, C. W., Barney, J. E., Helton, M. R., and Yobs, A. R., Measurement of atmospheric levels of pesticides, Environ. Sci. Technol., 5, 430, 1971.
151. Jutze, G. A. and Foster, K. E., Air Pollut. Contr. Assoc., 71, 1, 1967.
152. Compton, B. and Bjorklund, J., Design of a high-volume sampler for airborne pesticide collection, Paper presented at the 163rd Natl. Meet. American Chemical Soc, Boston, Mass., April, 1972.
153. Armour, J. A., Quantitative perchlorination of polychlorinated biphenyls as a method for confirmatory residue measurement and identification, J. Assoc. Off. Anal. Chem., 56, 987, 1973.
154. Suess, M. J., The environmental load and cycle of polycyclic aromatic hydrocarbons, Sci. Total Environ., 6, 239, 1976.
155. Particulate Polycyclic Organic Matter, National Academy of Science, Washington, D.C., 1972.
156. Lunde, G. and Bjorseth, A., Polycyclic aromatic hydrocarbons in long-range transported aerosols, Nature (London), 268, 518, 1977.
157. Sherma, J. and Shafik, T. M., A multiclass, multiresidue analytical method for determining pesticide residues in air, Arch. Environ. Contam. Tox., 3, 55, 1975.
158. Braun, T. and Farag, A. B., Reversed-phase foamchromatography. Separation of palladium, bismuth and nickel in tributylphosphate-thiourea-perchloric acid system, Anal. Chim. Acta, 61, 265, 1972.
159. Braun, T. and Farag, A. B., Reversed phase foam chromatography. Chemical enrichment and separation of gold in the tributyl phosphate perchloric acid system, Anal. Chim. Acta, 65, 115, 1973.
160. Braun, T., Bakos, L., and Szabó, Zs., Reversed phase foam chromatography. Separation of iron from copper, cobalt and nickel in the tri-n-butylphosphate-hydrochloric acid system, Anal. Chim. Acta, 66, 57, 1973.
161. Uthe, J. F., Reinke, J., and Gesser, H. D., Extraction of organochlorine pesticides from water by porous polyurethane coated with selective absorbent, Environ. Lett., 3, 117, 1972.
162. Braun, T. and Farag, A. B., Use of cellular plastics in extraction chromatography, in Extraction Chromatography, Braun, T. and Ghersini, G., Eds., Elsevier-Akadémiai Kiadó, Amsterdam-Budapest, 1975, 334.
163. Braun, T. and Farag, A. B., Plasticized open-cell polyurethane foam as a universal matrix for organic reagents in trace element preconcentration. I. Collection of silver traces on dithizone foam, Anal. Chim. Acta, 69, 85, 1974.
164. Braun, T. and Farag, A. B., Plasticized open-cell polyurethane foam as a universal matrix for organic reagents in trace element preconcentration. II. Collection of mercury traces on dithizone and die-thyldithiocarbamate foams, Anal. Chim. Acta, 11, 133, 1974.
165. Chow, A. and Buksak, D., The extraction of mercury and methylmercury by diphenylthiocarbazone-treated polyurethane foams, Can. J. Chem., 53, 1373, 1975.
166. Braun, T. and Palágyi, S., Pulsating column separations with a polyurethane foam syringe, Anal. Chem., 51, 1697, 1979.
167. Carritt, D. E., Separation and concentration of trace metals from natural waters: partition chromatographic technique, Anal. Chem., 25, 1927, 1953.
168. Pierce, T. B. and Peck, P. F., A rapid method for determining indium by neutron activation, Analyst, 86, 580, 1961.
169. Braun, T. and Farag, A. B., Plasticized open-cell polyurethane foam as a universal matrix for organic reagents in trace element preconcentration. III. Collection of cobalt traces on l-nitroso-2-naphthol and diethyldithiocarbamate foams, Anal. Chim. Acta, 76, 107, 1975.
170. Valente, I. and Bowen, H. J. M., Method for the separation of antimony(IIl) from antimony(V) using polyurethane foam, Analyst, 102, 842, 1977.
171. Braun, T., Abbas, M. N., Bakos, L., and Elek, A., Preconcentration of phenylmercury, methylmer-cury and inorganic mercury from natural waters with diethylammonium diethyldithiocarbamate-loaded polyurethane foam, Anal. Chim. Acta, 131, 311, 1981.
172. Lypka, G. N., Gesser, H. D., and Chow, A., Foam chromatography. The extraction and separation of a copper cadmium system by benzoylacetone-treated polyurethane foam, Anal. Chim. Acta, 78, 367, 1975.
173. Lee, D. W. and Halmann, M., Selective separation of nickel(ll) by dimethylglyoxime-treated polyurethane foam, Anal. Chem., 48, 2214, 1976.
174. Gregoire, D. C. and Chow, A., Separation of platinum and palladium with silicone-rubber foam treated with dimethylglyoxime, Talanta, 22, 453, 1975.
175. Halmann, M. and Lee, D. W., Recovery of nickel from ammoniacal media with dioxime-loaded open-pore polyurethane foams, Anal. Chim. Acta, 113, 383, 1980.
176. Halmann, M. and Lee, D. W., Conf. Cellular and Noncellular Polyurethanes, Strassbourg, Hauser Verlag, Miinchen, Wien, June, 1980, 821.
177. Valente, I. and Bowen, H. J. M., A method of concentrating antimony from natural waters, Anal. Chim. Acta, 90, 315, 1977.
178. Braun, T. and Abbas, M. N., Spectrophotometric determination of traces of cobalt in water after preconcentration on reagent-loaded polyurethane foams, Anal. Chim. Acta, 119, 113, 1980.
179. Srikameswaran, K. and Gesser, H. D., A novel method for the concentration and determination of trace elements in water, J. Environ. Sci. Health, A13, 415, 1978.
180. Srikameswaran, K., Gesser, H. D., and Venkateswaran, M., Monitoring trace amounts of cadmium in natural waters, J. Environ. Sci. Health, A15, 323, 1980.
181. Maloney, M. P., Moody, G. J., and Thomas, J. D. R., Extraction and separation of metal ions by foam-supported reagents, Proc. Anal. Div. Chem. Soc, 14, 244, 1977.
182. Vernon, F., Ion exchange on LIX 65N and Kelex 100 impregnated foams, Sep. Sci. Technol., 13, 587, 1978.
183. Braun, T., Trends in using resilient polyurethane foams as sorbents in analytical chemistry, Z. Anal. Chem., 314, 652, 1983.
184. Braun, T. and Farag, A. B., Chromofoams. Qualitative and semiquantitative tests with chromogenic organic reagents immobilized in open-cell polyurethane foams, Anal. Chim. Acta, 73, 301, 1974.
185. Farag, A. B., El-Wakil, A. M., and El-Shahawi, M. S., Qualitative and semiquantitative determination of chromium(VI) in aqueous solution using 1,5-diphenylcarbazide-loaded foam, Analyst, 106, 809, 1981.
186. Farag, A. B., El-Wakil, A.M., and El-Shahawi, M.S., Detection and semiquantitative determination of nickel with dimethyl-glyoxime-loaded foam, Talanta, 29, 789, 1982.
187. Farag, A. B., El-Wakil, A. M., and El-Shahawi, M. S., Qualitative and semiquantitative determination of iron(Ill) in aqueous thiocyanate solution using tricapylylamine foam, Ann. Chim. (Roma), 72, 103, 1982.
188. Farag, A. B., Morsi, M. A., and Ibrahim, S. A., Qualitative and semiquantitative determination of copper(II) in aqueous solution using biacetylmonooxime benzoyl hydrazone, to be published.
189. Fujimoto, M. and Nakatsukasa, Y., Microanalysis with aid of ion exchangers XXI. Modifications of resin spot test with high molecular weight amines, Anal. Chim. Acta, 27, 373, 1962.
190. Tanaka, T., Hiiro, K., and Kawahara, A., Simple colorimetric determination of phosphate ion using polyurethane foam loaded with a mixture of liquid anion exchanger of molybdate form and tributyl phosphate, Bunseki Kagaku (Jap. Analyst), 31, E123, 1982.
191. Braun, T., Huszár, É., and Bakos, L., Reverse-phase foamchromatography. Separation of trace amounts of cobalt from nickel in the tri-n-octylamine-hydrochloric acid system, Anal. Chim. Acta, 64, 77, 1973.
192. Baghai, A. and Bowen, H. J. M., Separation of rhodium and iridium using silicone-rubber foam treated with tri-n-octylamine, Analyst, 101, 661, 1976.
193. El-Wakil, A. M., Farag, A. B., and Ez-Eldin, A. Kh., Separation of iron, cobalt, nickel and cadmium in aqueous acid halide solution using Aliquat-foam columns, Sep. Sci. Technol., 17, 1085, 1982.
194. Xie Chang-Sheng, The enrichment with impregnated polyurethane foam and spectrophotometric determination of trace thorium in natural water, Acta Chim. Sinica, 40, 605, 1982.
195. Kirkland, J. J., Techniques for high-performance liquid-liquid and ion exchange chromatography with controlled surface porosity column packings, J. Chromatogr. Sci., 7, 361, 1969.
196. Horváth, C. G., Preiss, A. B., and Lipsky, S. R., Fast liquid chromatography: an investigation of operating parameters and separation of nucleotides on pellicular ion exchangers, Anal. Chem., 39, 1422, 1967.
197. Skafi, M. and Lieser, K. H., Preparation and properties of superficially sulfonated exchange resins, Z. Anal. Chem., 249, 182, 1970.
198. Skafi, M. and Lieser, K. H., Selectivity of superficially sulphonated exchange resins, Z. Anal. Chem., 250, 306, 1970.
199. Skafi, M. and Lieser, K. H., Rapid column separations by means of a superficially sulfonated exchange resin, Z. Anal. Chem., 251, 177, 1970.
200. Pinfold, T. A. and Karger, B. L., The coagulation of finely-divided ion exchange resins and use of coagulated material for rapid ion removal, Sep. Sci., 5, 183, 1970.
201. Braun, T., Bekeffy, O., Haklits, I., Kadar, K. and Majoros, G., Ion-exchange foamchromatography. I. Preparation of rigid and flexible ion-exchange foams, Anal. Chim. Acta, 64, 45, 1973.
202. Mazurski, M. A., Chow, A., and Gesser, H. D., Extraction of mercury from aqueous-solution with sulfide-treated polyurethane foam, Anal. Chim. Acta, 65, 99, 1973.
203. Braun, T. and Farag, A. B., Ion-exchange foamchromatography. II. Rapid separations on heterogeneous cation exchange foams, Anal. Chim. Acta, 68, 119, 1974.
204. Braun, T., Farag, A. B., and Klimes-Szmik, A., Reversed phase foam chromatography. Redox reactions on polyurethane foam columns supporting tetrachlorophydroquinone, Anal. Chim. Acta, 64, 71, 1973.
205. Braun, T. and Farag, A. B., Pulsed column redox techniques with flexible foam fillings, Anal. Chim. Acta, 65, 139, 1973.
206. Cerrai, E. and Testa, C, Electron-exchange processeson simple columns of Kel-F supporting tetrach-lorohydroquinon, Anal. Chim. Acta, 28, 205, 1963.
207. Environmental Surveillance Around Nuclear Installations, Vols. 1 and 2, Proc. Ser., IAEA, Vienna, 1974.
208. Faure, M., Nuclear-power plantsand environment, Kerntechnik, 16, 490, 1974.
209. Meyer, P., Nuclear-energy andenvironment, Kerntechnik, 19, 9, 1977.
210. Mielken, G. and Will, M., Release and deposition of fission-products in high-temperature reactors, Kerntechnik, 18, 61, 1976.
211. Sunderman, D. N. and Meinke, W. W., Evaluation of radiochemical separation procedures, Anal. Chem., 29, 1578, 1957.
212. Rudstam, G. and Sorensen, G., Fission and spallation yields in iodine region, J. Inorg. Nucl. Chem., 28, 771, 1966.
213. Schiissler, H. D. and Herrmann, G., Schneller Austausch von Metallionen an Metallsulfidcellulosen, Radiochim. Acta, 13, 65, 1970.
214. Erdey, L., Gimesi, O., Szabo, E., and Csajka, M., Determination of trace contaminants in hydro-genation catalysts by neutron-activation analysis, Talanta, 17, 1157, 1970.
215. DeVoe, J. R., Kim, C. K., and Meinke, W. W., Radiochemical separations by amalgam exchange, Talanta, 3, 298, 1960.
216. Qureshi, I. H. and Nagi, F. I., Radiochemical separation of lead by amalgam exchange, Talanta, 14, 323, 1967.
217. Kim, C. K. and Silvermann, J., Determination of mercury in wheat and tobacco leaf by neutron activation analysis using mercury-197 and a simple exchange separation, Anal. Chem., 37, 1616, 1965.
218. Okashita, H., Rapid separation of radionuclides by spontaneous electrodeposition of metallic mercury. I. Metallic mercury-mercury ion system, Radiochim. Acta, 7, 81, 1967.
219. Ikeda, N., Kimura, K., Hasebe, N., and Shoji, H., A new possibility for method of activation analysis of uranium, Radiochim. Acta, 12, 72, 1969.
220. Palágyi, S., Some theoretical aspects of use of isotopic-exchange in a heterogeneous liquid-system for radiochemical separations, J. Radioanal. Chem., 21, 47, 1974.
221. Heurtebise, M. and Ross, W. J., Application of an iodide-specific resin to determination of iodine in biological-fluids by activation analysis, Anal. Chem., 43, 1438, 1971.
222. Heurtebise, M. and Ross, W. J., Radiochemical separations with halogenated resins, Anal. Chem., 44, 596, 1972.
223. Braun, T. and Farag, A. B., Static and dynamic isotope exchange separations on finely divided precipitates immobilized in open-cell polyurethane foams, Radiochem. Radioanal. Lett., 19, 275, 1974.
224. Braun, T. and Farag, A. B., Static and dynamic redox exchange separations on finely divided copper immobilized in open-cell polyurethane foam, Radiochem. Radioanal. Lett., 19, 377, 1974.
225. Gimesi, O. and Bányai, É., New micro-methods for the determination of radio-iodine, Mikrochim. Acta,!, 313, 1981.
226. Braun, T. and Farag, A. B., Static and dynamic isotope exchange separations on hydrophobic organic phases immobilized open-cell polyurethane foams, J. Radioanal. Chem., 25, 5, 1975.
227. Eckhardt, W., Herrmann, G., and Schiissler, H. D., Schnelle radiochemische trennungen durch iso-topen- und ionenaustausch an vorgeformten niederschlagen, Z. Anal. Chem., 226, 71, 1967.
228. Palágyi, S. and Markusová, R., Rapid separation of radioiodine from milk by a polyurethane foam column-filtration method, Radiochem. Radioanal. Lett., 32, 103, 1978.
229. Palágyi, S. and Bilá, E., Separation of radioiodine by static and dynamic isotope exchange on hydrophobic organic phases immobilized in open-cell polyurethane foam, Radiochem. Radioanal. Lett., 32, 87, 1978.
230. Palágyi, S. and Braun, T., 180th Natl. A.C.S. Meeting, Las Vegas, American Chemical Society, Washington, D.C., 1980.
231. Palágyi, S. and Braun, T., Pulsating column separation and preconcentration of radioiodine on hydrophobic organic reagent loaded resilient open-cell polyurethane foam, J. Radioanal. Chem., 51, 267, 1979.
232. Palágyi, S. and Braun, T., Open-cell polyurethanefoam as sorbent in the extraction of iodine-131, Analyst, 106, 1326, 1981.
233. Palágyi, S., Preparation of samples for radioactivity measurements using pulsed bed column separation and preconcentration, Proc. 2nd Int. Conf., Low Radioactivities '80, The High Tatras, Strbske Pleso, Czechoslovakia, 1980.
234. Farag, A. B., Attia, M. E., and Hassan, H. N. A., Polyurethane foam as a new external absorbent in elemental microanalysis. Simultaneous determination of carbon, hydrogen and iodine in iodo-organic compounds, Indian J. Chem., B20, 693, 1981.
235. Farag, A. B., Attia, M. E., and Hassan, H. N. A., Simultaneous microdetermination of carbon, hydrogen and mercury in organomercury compounds by various combustion methods, Anal. Chem., 52, 2153, 1980.
236. Farag, A. B., Attia, M. E., and Hassan, H. N. A., Simultaneous microdetermination of carbon, hydrogen, and chlorine or bromine in organic compounds by various rapid empty-tube combustion methods, Talanta, 27, 1093, 1980.
237. Klimova, V. A. and Dubinskii, R. A., Formation of nitrogen oxides during the determination of carbon and hydrogen by the flash burning of aromatic nitro-compounds in an oxygen stream, Izv. Akad. Nauk SSSR, Ser. Khim., 191, 1969.;
238. Analyt. Abstr., 18, 3146, 1970.
239. Gawargious, Y. A. and MacDonald, A. M. G., in Proc. 1961 Int. Symp. Microchemical Techniques, Vol. 2, Wiley-Interscience, New York, 1962.
240. Belcher, R., Gibbons, D., and Sykes, A., Determination of metals in organic compounds, Mikro-chim. Acta, 40, 76, 1952.
241. Gawargious, Y. A. and Farag, A. B., The simultaneous microdetermination of carbon, hydrogen and halogen in highly chlorinated or brominated organic compounds, Mikrochem. J., 16, 333, 1971.
242. Bauman, E. K., Goodson, L. H., Guilbault, G. G., and Kramer, D. N., Preparation of immobilized cholinesterase for use in analytical chemistry, Anal. Chem., 37, 1378, 1965.
243. Bauman, E. K., Goodson, L. H., and Thomson, J. R., An immobilized cholinesterase product for use in the rapid detection of enzyme inhibitors in air or water, Anal. Biochem., 19, 587, 1967.
244. Goodson, L. H. and Jacobs, W. B., A rapid detection system for organophosphates in water, in Control of Hazardous Material Spills, U.S. Environmental Protection Agency, Washington, D.C., 1973, 129.
245. Goodson, L. H., Jacobs, W. B., and Davis, A. W., An immobilized cholinesterase product for use in the rapid detection of enzyme inhibitors in air or water, Anal. Biochem., 51, 362, 1973.
246. Goodson, L. H. and Jacobs, W. B., Proc. Natl. Conf. Control of Hazardous Material Spills, American Institute of Chemical Engineers, New Jersey, 1974, Environmental Protection Agency, Washington, D.C., 1974, 292.
247. Evans, W. H., Mage, M. G., and Peterson, E. A., A method for the immunoabsorption of cells to an antibody-coated polyurethane foam, J. Immunol., 102, 899, 1969.
248. Salyer, I. O., Schwendeman, J. L., and Jefferson, R. T., Polyurethane precipitation foam, presented at the 156th Natl. American Chemical Society Meeting, September 8-14, 1968.
249. Salyer, I. O., Jefferson, R. T., and Ross, W. D., Chromatographic medium and method, U.S. Patent 3,580,843, 1971.
250. Ross, W. D. and Jefferson, R. T., In situ-formed open pore polyurethane as chromatography supports, J. Chromatogr. Sci., 8, 386, 1970.
251. Hileman, F. D., Sievers, R. E., Hess, G. G., and Ross, W. D., In situ preparation and evaluation of open pore polyurethane chromatographic columns, Anal. Chem., 45, 1126, 1973.
252. Hileman, F. D., In-situ preparationand evaluation of open pore polyurethane chromatographic columns, Master of Science thesis, Wright State University, Dayton, Ohio, 1973.
253. Chen, T. M., Hess, G. G., and Sievers, R. E., Improvements in gas-chromatographic columns formed by in-situ polymerization, J. Chromatogr., 134, 170, 1977.
254. Lynn, T. R., Rushneck, D. R., and Cooper, A. R., High resolution low pressure liquid-chromatog-raphy, J. Chromatogr. Sci., 12, 76, 1974.
255. Hansen, L. C. and Sievers, R. E., Highly permeable open-pore polyurethane columns for liquid-chromatography, J. Chromatogr., 99, 123, 1974.
256. Herman, D. P. and Field, L. R., Surface-modified open-pore polyurethane packings for liquid chromatography, J. Chromatogr. Sci., 20, 55, 1982.
257. Navratil, J. D., Sievers, R. E., and Walton, H. F., Open-pore polyurethanecolumns for collection and preconcentration of polynuclear aromatic-hydrocarbons from water, Anal. Chem., 49, 2260, 1977.
258. Smith, C. M. and Navratil, J. D., Removal and preconcentration of surfactants from wastewater with open-pore polyurethane, Sep. Sci. Technol., 14, 255, 1979.
259. Smith, C. M., Navratil, J. D., and Plock, C. E., Waste management analysis for the nuclear fuel cycle. 11. Recycle preparation for wastewater streams, U.S. Department of Energy Report RFP-2813, Rockwell International, Golden, Colorado, 1979.
260. Denton, M. S., Dinsmore, S. R., Brand, J. I., Beams, J., and Ball, F. L., Open-pore polyurethaneas a medium for coal conversion process aqueous effluent cleanup, Sep. Sci. Technol., 15, 587, 1980.
261. Jefferson, R. T. and Salyer, I. O., Open-pore polyurethaneproduct, U.S. Patent 3,574,150,1971.
262. Ross, W. D., Open-pore polyurethane. A new separation medium, in Separation and Purification Methods, Vol. 3, Perry, E. S., van Oss, C. J., and Grushka, E., Eds., Marcel Dekker, New York, 1974, 111.
263. Navratil, J. D. and Sievers, R. E., Chemical separations with open-pore polyurethane, Am. Lab., 9, 38, 1977.
264. Usmani, A. M. and Salyer, I. O., Open-pore polymerstructures. A review, Polym.-Plast. Technol. Eng., 12, 61, 1979.
265. Doyles, E. N., The Development and Use of Polyurethane Products, McGraw-Hill, New York, 1971.
266. Salyer, I. O., Jefferson, R. T., Pustinger, J. V., and Schwendeman, J. L., Preparation and properties of open-pore polyurethane (OPP), J. Cell. Plast., 9, 25, 1973.
267. Kutal, K. C. and Sievers, R. E., A rate and equilibrium study of the cis- trans isomerization of tris(l,l,l-trifluoro-2,4-pentanedianato) chromium(III) in the gas phase, presented 166th Natl. Meet., American Chemical Society, Chicago, Illinois, August, 1973.
268. Salyer, I. O. and Jefferson, R. T., Cigarette filter, U.S. Patent 3,746,014, 1975.
269. Salyer, I. O. and Jefferson, R. T., Porous structure and method, U.S. Patent 3,647,721, 1973.
270. Navratil, J. D., Rockwell International, Golden, Colorado, private communication, 1983.