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Selected reading papers:

1. "Explanation of Misleading Nernst Slope by Boltzmann Equation"

2. "Counterion Triple Layer for Explaining Stirring and Temperature Effects on pH Measurements"

Dr. K. L. Cheng is Professor of Chemistry Emeritus, University of Missouri-Kansas City. He received his B. S. degree from the Northwestern College, China in 1941, his M. S. in 1949, and his Ph.D. in 1951 from the University of Illinois. Dr. Cheng has been a postdoctoral fellow at the University of Illinois and an instructor at the University of Connecticut, Department of Chemistry. Dr. Cheng is a member of the American Chemical Society, Electrochemical Society, American Microchemical Society, Society for Applied Spectroscopy, and American Institute of Physics. He is a fellow of the American Association for Advancement of Science and of the Royal Society of Chemistry, London. He is also a member of Sigma Xi, Sigma Pi Sigma, and Phi Lambda Upsilon.

Dr. Cheng received his RCA Achievement Award in 1963. He was elected titular member of the Division of Analytical Chemistry, International Union of Pure and Applied Chemistry (1969-1979). He received the N. T. Veatch Award for Distinguished Research and Creative Activity and the Certificate of Recognition from the U. S. Office of Naval Research in 1979, and that from the College of Engineering , Texas A&M University, 1981.

He received the Benedetti-Pichler Memorial Award for Microchemistry in 1989. He is the co-author of the "Handbook of Organic Analytical Reagents". He has published chapters in many books and more than 200 papers. He is one of the pioneers of EDTA analytical chemistry. EDTA titration and the use of 1-(2- pyridylazo)- 2-naphthol (PAN) as a metal indicator and photometric reagent were included in his 1951 dissertation. In the past decade, he proposed his double chemical capacitor theory for the ion selective electrodes. He called attention to the misuse of the Nernst equation and disproved the ion exchange reaction between H+ and Na+ in the pH glass electrode. He challenged many past misconceptions and emphasized the importance of clear definition and right assumption.

His areas of research interest include surface chemistry and techniques, membrane electrodes, chemical separation, organic reagents, and aging.


Paper Published by Dr. K. L. Cheng and His Co-workers Relating to ISE:
Pre-Chemical Capacitor Concept Period: Studying Potential Origin
  1. S. Kar Chaudhari and K. L. Cheng, "Effect of organic solvents and their dielectric constants on ion- selective electrode potential" Mikrochim. Acta. II. 411-70 (1979)
  2. S. Kar Chaudhari and K. L. Cheng, "Radioactive trace study of adsorption and exchange reaction of lead sulfide ion-selective electrode membrane" Mikrochim. Acta, II, 159-70 (1980)
  3. K. L. Cheng, "Some properties of lead ion-selective electrode" Presented at 180th ACS National Meeting, Las Vegas, NV, August, 1980
  4. S. Kar Chaudhari and K. L. Cheng, "Effect of electrode membrane surface ratio and thickness on lead electrode potential" Mikrochim. Acta, I, 185-90 (1981)
  5. K. L. Cheng and H. P. Chang, "The deviation potential of pH glass electrode" Mikrochim. Acta, I, 95-101 (1985)

    Misconceptions

  6. K. L. Cheng, "Some comments on the relationship of pH and potential" Microchem. J., 33, 132-3 (1986)
  7. Naila Ashraf and K. L. Cheng, "Nonlinear response of pH glass electrode" Presented at the ACS National Meeting, Miami, FL, September 1989
  8. Naila Ashraf and K. L. Cheng, "Nonlinear response of pH glass electrode" Presented at the ACS Rocky Mountain Regional Meeting, Denver, CO, 1990
  9. K. L. Cheng, "Misuse of the Nernst equation in the nonfaradaic potentiometry" Presented at the ACS National Meeting, Atlanta, GA, April 1991
  10. K. L. Cheng, "The second Nernstian hiatus" Presented at the Pittsburgh Conference, March 1992
  11. K. L. Cheng, "Misleading ion activity concept in nonfaradaic potentiometry" presented at the ACS National Meeting, Anaheim, CA, April 1995.
  12. Chia-Ming Huang, Y. C. Jean, K. L. Cheng, and F. C. Chang, "Isotopic evidence disproving ion exchange reaction between H+ and Na+ in pH glass electrode" J. Electrochem. Soc., 142, L176 (1995)
  13. K. L. Cheng, "A critical review of ion activity and ion activity coefficient concepts" Presented at the Pittcon, Atlanta, GA, March 1997

    Theory

  14. K. L. Cheng, "Chemical capacitor theory" Presented at the seminar in the Emory University, Atlanta, GA, March 13, 1984
  15. K. L. Cheng, "A capacitor model for membrane electrodes" In proceedings, 31st IUPAC Congress, Anal. Chem. Div., pp 173-197, 1987. Sofia, Burgaria
  16. K. L. Cheng, "Capacitor theory for nonfaradaic potentiometry" Microchem. J., 42, 5-24 (1990) A Benedetti-Pichler award address given on September 28, 1989
  17. K. L. Cheng, "pH glass electrode and its mechanism" in Electrochemistry, Past and Present, ACS Symposium Series No. 390, J. T. Stock and M. V. Orno, Eds., pp. 286-302 (1989)
  18. Kuang L. Cheng, Hung Z. Song, and Susie X. R. Yang, "Evidence of adsorption of hydrogen and hydroxide ions by pH-sensitive glass, and chemical potential amplification" J. Chem. Soc., Chem. Commun., 1333-4 (1988)
  19. K. L. Cheng, "Membrane electrode as a chemical capacitor" Presented at the 201st ACS National Meeting, Atlanta, GA April 1991
  20. Susie X. R. Yang and K. L. Cheng, "Capacitance of membrane electrodes" Presented at the ACS National Meeting, Dallas, TX, 1989
  21. K. L. Cheng, "Neglect of anions in potentiometry" Presented at the ACS National Meeting, Chicago, IL, August 1995
  22. Susie X. Yang, Naila Ashraf, and K. L. Cheng, "Amplification potential of glass electrode" Part of the Ph.D. dissertation: "New development of understanding the mechanism of pH glass electrode" University of Missouri-Kansas City, 1991. (To be published)
  23. Susie X. Yang, and K. L. Cheng, "Electrode membrane capacitance measurement" Ph.D. dissertation: "New developments of nonfaradaic potentiometry" University of Missouri-Kansas City, 1988. (To be published)
  24. Susie X. Yang, and K. L. Cheng, "Electrode thickness effect on potential" In Yang's Ph.D. dissertation, 1988. (To be published)
  25. K. L. Cheng, "Junction potential" (To be published)
  26. K. L. Cheng, Letter to Editor. Electrochemical "Homeopathy", SEAC Communications. Vol. 12, No. 3, 1996.
  27. Susie X. Yang, Naila Ashraf, and K. L. Cheng, "Charging, discharging, and recharging of electrodes" Parts of Ph.D. dissertation by Yang and Ashraf, University of Missouri-Kansas City, 1988 and 1991. (To be published)

    Patent

  28. K. L. Cheng and Eric E. Chao "An arsenite ion-selective electrode" U.S. Patent No. 4071427, January 1978
  29. K. L. Cheng "Potential measuring method and applications having signal amplifying multiple membrane electrode" U.S. Patent No. 4,886,584 , December 1989

    Solid State Membrane

  30. S. Kar Chaudhari and K. L. Cheng, "Recent study of solid surfaces by photoelectron spectroscopy" Appl. Spectros. Revs. 16, 187-297 (1980)
  31. K. L. Cheng and Naila Ashraf "A simple solid state pH glass electrode" Talanta, 37, 629 (1990)
  32. K. Hamdani and K. L. Cheng, "Modified polymer electrode" Presented at the 201st ACS National Meeting, Atlanta, GA (1991)
  33. K. Hamdani and K. L. Cheng, "Adsorption of biochemically significant phosphates on silica" Colloids and Surfaces, 63, 29-31 (1992)
  34. Naila Ashraf, K. Hamdani and K. L. Cheng, "Solid state pH and pNa glass electrodes" In Advances in the Applications of Membrane Mimetic Chemistry. T.F. Yen, et al. eds. Plenum, New York. pp 209-225 (1994)
  35. K. Hamdani and K. L. Cheng, "Polyaniline pH electrode" Microchem. J. 61, (1999) 198
  36. Y. S. Su and K. L. Cheng, and Y. C. Jean, "Amplified potentiometric determination of pK00, pK0, pK1and pK2 of hydrogen sulfides with Ag2S ISE" Talanta, 44, 1757 (1997)

    Interference

  37. K. L. Cheng, Jui-Chi Hung, and David H. Prager "Determination of exchangeable calcium and magnesium in soil by ion selective electrode method" Microchem. J., 18, 256-61 (1973)
  38. K. L. Cheng and Katherin Cheng, "Selective determination of magensium in water with divalent ion selective electrode using GDTA as a masking agent" Mikrochim. Acta, I, 385-90 (1974)
  39. S. Kar Chaudhari, F. C. Chang, K. L. Cheng and V. Y. Young, "Determination of the surface composition of lead electrode membranes by ESCA" Anal. Chem., 53, 2048 (1981)
  40. V. Y. Young, S. Kar Chaudhari and K. L. Cheng, "ESCA studies of the effect of bivalent metal ions on lead ion-selective electrode membrane" Surface Interface Anal., 3, 176 (1981)
  41. Susie X. R. Yang, K. L. Cheng, L. T. Kurtz, and R. H. Peck, "Suspension effect on potentiometry" Particulate Science and Technology, 7, 139-52, (1989)
  42. Ching-I Huang, Hsuan Jung Huang, and K. L. Cheng "Effect of Stirring on pH Measurements" In Advances in the Applications of Membrane Mimetic Chemistry. T.F. Yen, et al. eds. Plenum, New York. pp 227-240 (1994)
  43. Y. S. Su and K. L. Cheng "Interference of pH glass electrode containing La2O3 or Nd2O3 caused by phosphate and flouride adsorptions" to be presented at the Eastern Anal. Symposium, Somerset, NJ, November 1997

    Application

  44. E. Moya and K. L. Cheng "Triethylenetetraminehexaacetic acid titration using ion-selective electrodes" Anal. Chem., 42, 1669-72 (1970)
  45. K. L. Cheng "New applications of divalent ion electrode" Presented at the IUPAC International Symposium on Ion-selective Electrode" Caldiff, U. K. April 11, 1973
  46. F. C. Chang and K. L. Cheng "Determination of tri- and tetravalent ions with a divalent ion-selective electrode" Anal. Chim. Acta, 76, 177-82 (1975)
  47. E. E. Chao and K. L. Cheng "Stepwise titration of some anions and determination of Ksp of silver precipitates with silver ion selective electrode" Anal. Chem., 48, 287 (1976)
  48. E. E. Chao and K. L. Cheng "The solubility products of some slightly soluble lead salts and the potentiometric titration of molybdate, tungstate, perrhenate and fluoride with use of a lead ion-selective electrode" Talanta, 24, 247 (1977)
  49. K. L. Cheng "Ion-selective electrodes as anion sensors" Proc. of the 7th Australian Electrochem. Conf., University of New South Wales, 406-9 (1988)
  50. Derren Lee and K. L. Cheng "An anion ion-selective electrode based on a mixture of insoluble lead salt" Talanta, 37, 901-4 (1990)
  51. Derren Lee and K. L. Cheng "ISE determination of molybdate, tungstate, perrhenate, fluoride, phosphate, and hydroxide with mixed lead salts of molybdate, tungstate, perrhenate" Presented at Pittsburgh Conference, Atlanta, GA, March 1989.
  52. K. Hamdani and K. L. Cheng "Solid state LaPO4 Electrode" in Ph.D. dissertation, "Metal-based thin film electrodes" University of Missouri - Kansas City, 1991.