將高分子塗布在石英振盪晶片可藉由石英震盪晶片上荷重的改變造成的頻率變化而求得高分子吸收溶劑量對時間的變化。
我們使用數值方法模擬雙成分溶劑在高分子中之吸收曲線，藉以找出吸收曲線的特徵，並利用類神經網路計算判斷溶劑的成分。為了瞭解利用單一石英振盪晶片作為多成分物質感測器的可行性，以一系列不同擴散係數與平衡吸收量找出可行的範圍。

雖然對於擴散係數小的溶劑在高分子中擴散可能會需要很長的時間才會達平衡，而在本研究中並不需要使兩種溶劑在同時在高分子中擴散達平衡，而只需要讓擴散快的溶劑達平衡。以下面三種參數當成類神經網路的判斷條件；(a) 吸收曲線在剛吸收的極短時間內的斜率（第一斜率）；(b) 其中某一溶劑擴散達平衡後的斜率（第二斜率）；(c) 或是在設定時間的吸收量。研究結果發現除了在擴散係數與平衡吸收量呈反比的情況下，使用第二斜率與吸收量當成判斷條件都可達到不錯的結果，並以水與丙酮作為實驗系統驗證之。

The sorption curves of solvent in polymer can be obtained from the shift of resonance frequency of quartz crystal coated with polymer in contact with solvent vapor environment. In this study, we simulate sorption curves of several binary solvent systems by assuming perfect Fickian diffusion behaviors. Several characteristic values of sorption curves can be obtained, i.e., the initial slope, the second slope after the first solvent which diffuses faster reaches equilibrium, and the amount of sorption at a specified time. These values can be used to train the neural network (NN) to calculate the concentrations of solvents of a particular sorption curve.

We have studied the influence of the ratio of diffusion coefficients and the ratio of the equilibrium sorption amounts of solvent 1 to sol-vent 2 in the polymer films. It is found that the second slope and the amount of sorption at some specified time can be used to train the NN to yield satisfactory results except for the case when the solvent with lower equilibrium sorption amount diffuses faster.

Experiments are also carried out for water/acetone/PVAc (poly vinyl acetate) systems. It is found that solvent concentrations of the environment can be obtained by feeding the characteristic values of sorption curves to a well-trained NN.

1. Auge, J., Hauptmann, P., Hartmann, J., Rösler, S.; and Lucklum, R.,’ Versatile microcontrolled gas sensor array system using the quartz microbalance principle and pattern recognition methods’ , Sensors and Actuators, B26-27, 181(1995).

2. Bonner, D. C. and Prausnitz, J. M., AIChE. J., 19, 943(1973).

3. Bruckenstein, S., and Shay, M., Electrochimica Acta, 30, 10, 1295(1985).

4. Brakó, G., Papp, B., and Hlavay, J.,‘ Application of an articial neu-ral network (ANN) and piezoelectric chemical sensor array for identification of volatile organic compounds‘, Talanta, 42(3), 475(1995).

5. Celda, B., Gavara, R., Gómez, C., Tejero, R., and Campos, A., Poly-mer, 30, 897(1989).

6. Chang, P., and Shih, J.-S.,’ Multi-channel piezoelectric quartz crys-tal sensor for organic vapours’ Analytica Chimca Acta, 403, 39(2000).

7. Curie, J., Curie, P.,‘ An oscillating quartz crystal mass dector’, Rendu, 91 (1880) .

8. Crank , J., The Mathematics of Diffusion , 2nd Ed. Oxford University Press, London, p254-265(1975).

9. Flory, P. J., Principles of Polymer Chemistry, Cornell University Press, Ithaca, New York(1953).

10. Flory, P. J., J. Am. Chem. Soc., 87, 1833(1965).

11. Gemperline, P. J., Long, J. R., and Gregoriu, V. D., Anal. Chem, 63, 2313(1991).

12. Guilbault, G. G., and Tomita, Y., Anal. Chem., 52, 189(1980).

13. Guilbault, G. G., and Tomita, Y., Sensors and Actuators, 2, 43(1981).

14. He, X. W., Xing, W. L., and Fang, Y. H.,’ Identification of combus-tible material with piezoelectric crystal sensor array using pattern- recognition techniques’, Talanta, 44, 2033(1997).

15. Ho, M. H., Reitz, B., and Guilbault, G. G., Anal. Chem., 52, 1489(1980).

16. Hopfield, J., and Tank, D., Biological Cybernetics, 51, 141(1985).

17. Kasai, N., Sugimoto, I., Nakamura, M., and Katoh, T.,‘ Odorant diction capability of QCR sensors coated with plasma deposited organic films’, Biosensors & Bioelectronics, 14, 533(1999).

18. King W. H., ‘Piezoelectric sorption dector’, Anal. Chem., 36, 1735(1964).

19. King W. H., Res/Dev., 20(4), 28(1969a).

20. King W. H., Res/Dev., 20(5), 28(1969b).

21. Laatikainen, M., and Lindstrom, M., J. Membrane Sci., 29, 127(1986).

22. Lu, C., Applications of Piezoelectric Quartz Crystal Microbalances, El-sevier, p19-61(1984).

23. Minsky, M. L., and Papert, S. S., Perceptrons, MIT Press, Cambridge, MA (1969).

24. Mulder, M. H. V., and Smolders, C. A., J. Membrane. Sci., 17, 289(1984).

25. Nanto, H., Dougami, N., Mukai, T., Habara, M., Kusano, E., Kin-bara, A., Ogawa, T., and Oyabu, T.,‘ A smart gas sensor using polymer-film-coated quartz resonator microbalance‘ Sensors and Actuators, B66, 16(2000).

26. Ng, S. C., Zhou, X.C., Chen, Z. K., Miao, P., Chan, H. S. O., Li, S. F. Y., and Fu P.,‘ Quartz crystal microbalance sensor deposited with langmuir–blodgett films of functionalized polythiophenes and ap-plication to heavy metal ions analysis‘ Langmuir, 14, 1748(1998)

27. Nomura T., and Nagamune T., Anal. Chim. Acta, 155, 231(1983).

28. Pochly, J., and Zivny, A., Markromol. Chem., 184, 2081(1984).

29. Rumelhart, D. E., and McClelland J. L., Parallel Distributed Proc-essing , Vol. Ⅰ,Ⅱ, M.I.T. Press, Cambridge, MA(1986).

30. Sauerbrey G.,’ Use of quartz vibration for weighing thin films on a microbalance’, J. Physik., 155, 206(1959).

31. Sun, L.-X., and Okada T.,’ Simultaneous determination of the con-centration of methanol and relative humidity based on a single Nafion(Ag)-coated quartz crystal microbalance’ Analytica Chimica, 421, 83( 2000).

32. Xing, W.-L., and He, X.-W., ‘Kinetic determination of organic va-por mixtures with single piezoelectric quartz crystal sensor using artifical neural networks‘ Talanta, 44, 959(1997).

33. Zhou, R., Haimbodi, M., Everhart, D., and Josse, F., ‘ Poly-mer-coated QCR sensors for the detection of organic solvents in water ’, Sensors and Actuators, B35-36, 176(1996).

34. 王國欽, 成大化工碩士論文(1992).

35. 凌漢辰, 龍彥先, 「高分子溶解行為之探討」, Proceedings of the 24th ROC Symposium 2001, vol 17, p. 298(2001).

36. 葉怡成, 類神經網路模式應用與實作, 儒林圖書公司(1994).

37. 鄭興坤, 成大化工碩士論文(1994).