在許多探討大氣基本物理特性、輻射作用、雲霧形成機制、區域性能見度、全球氣候變遷、氣膠化學組成與人體健康風險評估等研究中，發現大氣氣膠的含水量皆佔有不可忽略的影響程度。氣膠含水量在大氣氣膠的物理與化學特性研究領域中佔有相當重要的地位。近年來已有許多學者對無機氣膠的吸濕成長進行相當多研究，但在有機氣膠方面則是剛剛起步，再加上有機物質對於氣膠吸濕特性又有許多不確定的影響，所以在有機氣膠的吸濕特性方面仍需更多的研究及數據來說明其對氣膠含水量的影響。
本研究主要是以GC-TCD氣膠含水量分析儀（Lee and Chang, 2002; Chang and Lee, 2002）量測收集在濾紙上大氣常見有機四種二元酸（Oxalic acid、Succinic acid、Malonic acid及Glutaric acid）的含水量，且將量測的數據與文獻量測單顆粒氣膠含水量相比較。此外，亦藉由GC/MS分析技術，分析大氣中常見的有機二元酸的成分與含量。
就有機酸成分分析結果顯示：以新莊超級測站這個採樣點來說，大氣氣膠中有機酸的平均濃度：Oxalic acid=167±36ng/M3、Malonic acid=15±4ng/M3、Succinic acid=14±4ng/M3、Glutaric acid=4±1ng/M3，總二元有機酸佔質量濃度的百分比為0.56%±0.13%，佔總碳濃度的4.60%±1.23%，佔有機碳濃度的7.55%±1.84%。
就GC-TCD量測有機氣膠含水量來說：GC-TCD法顯示Oxalic acid及Succinic acid氣膠並無DRH與CRH，其AMC分別為1.26及1.00；Malonic acid氣膠DRH=70-75%，在潮解點相對濕度後，氣膠仍會隨著相對濕度再升高持續吸水；無CRH；Glutaric acid氣膠的DRH＝90％。
就溫度對有機氣膠含水量的影響來說：在增濕過程中，當溫度越高時，氣膠大量吸水點會發生在較低的相對濕度環境下；而在降濕過程中，氣膠的含水量在同一相對濕度環境下，卻會隨溫度增加而增加。

Water content of atmospheric aerosols is related to atmospheric radiation, cloud and mist formation, visibility, local climate change, chemical and physical properties of aerosols, and human health assessment. As the results, the measurements of water content of aerosols become increasingly important in aerosol science research. Resently, many scholars have invested the hygroscopic characteristic of inorganic aerosols. However, few researches focused on similar topics of the organic aerosols. Because the hygroscopicity of organic aerosols is uncertain for now, it needs more scientific datas to realize the relationship between atmospheric moisture and hygroscopicity of organic aerosols related to water content within them.
In this research, a thermal conductivity detector (GC-TCD, Lee and Chang, 2002; Chang and Lee, 2002) was used to measure water content of four organic acids (Oxalic acid, Succinic acid, Malonic acid and Glutaric acid). The results of oxalic acid and succinic acid showed no DRH(Deliquescence Relative Humidity) and CRH(Crystallization Relative Humidity). AMC(Aerosol Mass Change) of oxalic acid and succinic acid indicated 1.26 and 1.00, respectively. The DRH of Malonic acid is at 70-75%. Water content of malonic acid increased with increasing relative humidity above DRH. However, malonic acid shows that CRH doesn’t exist. Glutaric acid reveals its DRH at 90%.
Applying GC/MS, the quantities of dicarboxylic acids were measured in associated with atmospheric aerosols. Air-borne particulate samples at Hsin-Chuang supersite from 19th September to 28th September. The average concentrations of oxalic acid, malonic acid, succnic acid and glutaric acid were 167±36 ng/M3, 15±4 ng/M3, 14±4 ng/M3, 4±1 ng/M3, respectively. The average percentage to four dicarboxylic acids was about 0.56%±0.13%. That total dicarboxylic acid mass concentration occupied 4.60%±1.23% and 7.55%±1.84% of total carbon and organic carbon concentrations.
The sensitivity of water content of organic aerosols was also influenced by temperature. During the experiments of increasing humidity, DRH of organic aerosols occurred at lower RH for higher temperatures. Contrastly, water content of organic aerosols increased with increasing temperature under the same humidity during the process of decreasing humidity.

Andrews, E., Larson, S.M., 1993. Effect of surfactant layers on the size changes of aerosol particles as a function of relative humidity. Environmental Science and Technology 27, 857-865.
Bassett, M., Seinfeld, J.H., 1984. Atmospheric equilibrium model of sulfate and nitrate aerosols Ⅱ. Particle size analysis. Atmospheric Environment 18, 1163-1170.
Boucher, O., Anderson, T.L., 1996. GCM assessment of the sensitivity of direct climate forcing by anthropogenic sulfate aerosols to aerosol size and chemistry. Journal of Geophysical Research 100, 26117-26134.
Chamberlian, A.C., Chadwick, R.C., 1953. Deposition of airborne radioiodine vapor. Nucleonics 8, 22-25.
Chan, C.K., Flagan, R.H., Seinfeld, J.H., 1992. Water activities of NH4NO3-(NH4)2SO4 solutions. Atmospheric Environment 26, 1661-1673.
Chan, C.K., Liang, Z., Zheng, J., Clegg, S.L., Brimblecombe, P., 1997. Thermodynamic properties of aqueous aerosols to high supersaturation: Ⅰ-measurements of water activity of the system Na+-Cl--NO3--SO42--H2O at ~ 298.15K. Aerosol Science and Technology 27, 324-344.
Chang, S.Y., Lee, C.T., 2002. Applying GC-TCD to investigate the hygroscopic characteristics of mixed aerosols. Atomspheric Environment 36, 1521-1530.
Cohen, M.D., Flagan, R.C., Seinfeld, J.H., 1987. Studies of concentrated electrolyte solutions using the electrodynamic balance: 2. Water activity for mixed-electrolyte solutions. Journal of Physical Chemistry 91, 4575-4582.
Curry, J.A., Schramm, J.L., Serreze, M.C., Ebert, E.E., 1995. Water vapor feedback over the Aretic Ocean. Journal of Geophysical Research 100, 14223-14229.
Cziczo, D.J., Nowak, J.B., Hu, J.H., Abbatt, J.P.D., 1997. Infrared spectroscopy of model tropospheric aerosols as a function of relative humidity: observation of deliquescence and crystallization. Journal of Geophysical Research 102, 18843-18850.
Denbigh, K., 1981. The principles of chemical equilibrium 4thed., Cambridge University Press, Cambridge.
Decesari, S., Facchini, M.C., Fuzzi, S., 2000. Characterization of water-soluble organic compounds in atmospheric aerosol: A new approach. Journal of Geophysical Research 105, 1481-1489.
Green, Don W., Maloney, James O., Perry, Robert H., 1984. Perry’s Chemical engineers’ handbook, New York: McGraw-Hill
Ha, Z., Choy, L., Chan, C. K., 2000. Study of water activities of supersaturated aerosols of sodium and ammonium salts. Journal of Geophysical Research 105D, 11699-11709.
Hameri, K., Charison, R, J., Hansson, H. C., Jaccobson, M., 1997. Hygroscopic properties of ammonium sulfate aerosols mixing with slightly soluble organic compoumd. Journal of Aerosol Science 28, S153-S154.
Han, J.H., Martin, S.T., 1999. Heterogeneous nucleation of the efflorescence of (NH4)2SO4 particles internally mixed with Al2O3, TiO2, and ZrO2. Journal of Geophysical Research 104, 3543-3553.
Hanel, G., 1976. The properties of atmospheric aerosol particles as functions of the relative humidity at thermodynamic equilibrium with the surrounding moist air. Advances in Geophysics 19, 74-183.
Hansson, H.C., Rood, M.J., Koloutsou-Vakakis, S., Hämeri, K., Orsini, D., Wiedensohler, A., 1998. NaCl aerosol particle hygroscopicity dependence on mixing with organic compounds. Journal of Atmospheric Chemistry 31, 321-346.
Hatakeyamas, S., Ohno, M., Weng, J., Takagi, H., Akimoto, H., 1987. Mechanism for the formation of gaseous and particulate products from ozone-cycloalkene reactions in air. Environmental Science and Technology 21, 52-57.
Hegg, D.A., Covert, D.S., Rood, M.J., Hobbs, P.V., 1996. Measurements of aerosol optical properties in marine air. Journal of Geophysical Research 101, 12893-12903.
Henry, R.C., 1997. The Application of The linear System Theory of Visual Acuity To Visibility Reduction by Aerosols. Enviromental Research and Technology, 697-701.
Hu, J.H., Abbatt, J.P.D., 1997. Reaction probilities for N2O5 hydrolysis on sulfuric acid and ammonium sulfate aerosols at room temperature, Journal of Physical Chemistry A 101, 871-878.
IPCC, 1992. Climate Change 1992. Cambridge University press.
IPCC, 2001. Climate Change 2001. Cambridge University press.
Kawamura, K., Gagosian, R.B., 1987. Implication of ω-oxocarboxylic acids in the remote marine atmosphere for photo-oxidation of unsaturated fatty acids. Nature 325, 330-332.
Kawamura, K., Ikushima, K., 1993. Seasonal changes in the distribution of dicarboxylic acids in the urban atmosphere. Environmental Science and Technology 27, 2227-2235.
Kawamura, K., Usukura, K., 1993. Distributions of low molecular weight dicarboxylic acids in the North Pacific aerosol sample. J. Oceanography 49, 271-283.
Kawamura, K., Kasukabe, H., 1995. Source and relation pathways of dicarboxylic acids, ketoacids and dicarbonyls in arctic aerosols: one year of observations. Atomspheric Environment 30, 1709-1722.
Kerminen, V., Teinilä, K., Hillamo, R., Mäkelä, T., 1999. Size-segregated chemistry of particulate dicarboxylic acids in the Arctic atmosphere. Atomspheric Environment 33, 2089-2100.
Khvorostyanov, V.I., Curry, J.A., 1999. A simple analytical model of aerosol properties with account for hygroscopic growth 2. Scattering and absorption coefficients. Journal of Geophysical Research 104, 2163-2174.
Khwaja, H.A., 1994. Atmospheric concentrations of carboxylic acids and related compounds at a semiurban site. Atomspheric Environment 29, 127-139.
Khwaja, H. A., Brudnoy, S., Husain, L., 1995. Chemical characterization of three summer cloud episodes at whiteface mountain. Chemosphere, 3357-3381.
Lee, W.M., Huang, W.M., Chen, Y.Y., 2001, Effect of relative humidity on mixed aerosols in atmosphere. Journal of Environmental Science and Health A36, No.4.
Lee, W.M., Shih, P.M., Wang, C.S., 1997, The influence of relative humidity on the size of atmospheric aerosol. Journal of Environmental Science and Health A32, No.4, 1085-1097.
Lee, C.T., Chang, S.Y., 2002. A GC-TCD method for measuring the liquid water mass of collected aerosols. Atomspheric Environment 36, 1883-1894.
Lee, C.T., Hsu,W.C., 1998. A Novel Method to Measure Aerosol Water Mass. Journal of Aerosol Science 29, 827-837.
Li,W., Hopke, P.K., 1994. Hygroscopic of consumer spray product aerosol particles. Journal of Aerosol Science 25, 1341-1351.
Li, W., Montassier, N., Hopke, P.K., 1992. A system to measure the hygroscopicity of aerosol particles. Aerosol Science and Technology 17, 25-35.
Lightstone, J.M., Onasch, T.B., Imre, D., 2000. Deliquescence, efflorescence, and water activity in ammonium nitrate and mixed ammonium nitrate/succinic acid microparticles. Journal of Physical Chemistry 104A, 9337-9346.
Limbeck, A., Puxbaum, H., Otter, L., Scholes, M. C., 2001. Semivolatile behavior of dicarboxylic acids and other polar organic species at a rural background sute ( Nylsvley, RSA ). Atmospheric Environment 35, 1853-1862.
Malm, William, C., Persha, 1991. Considerations in the Accuracy of a Long-Path Transmissometer . Aerosol Science and Technology 14, 459-471.
Martin, S.T., 1998. Phase transformations of the ternary system (NH4)2SO4-H2SO4-H2O and the implications for cirrus cloud formation. Geophysical Research Letter 25, 1657-1660.
McMurry, P.H., Zhang, X.Q., 1991. Optical properties of Los Angeles Aerosols: an analysis of data acquired during SCAQS. Final report to the Coordinating Research Council, 219 Perimeter Center Parkway, Atlanta, GA 30346.
Na, H.S., Arnold, S., Myerson, A.S., 1995. Water activity in supersaturated aqueous solution of organic solutes. Journal of Crystal Growth 149, 229-235.
Norton, R.B., Roberts, J.M., Huebert, B.J., 1983. Tropospheric oxalate. Geophys. Res. Lett. 10, 517-520.
Pandis, S.N., Cruz, C.N., 2000. Deliquescence and hygroscopic growth of mixed inorganic-organic atmospheric aerosol. Environmental Science and Technology 34, 4313-4319.
Peng, C., Chan, M.N., Chan, C.K., 2001. The Hygroscopic Properties of Dicarboxylic and Multifunctional Acids: Measurements and UNIFAC Prediction. Environmental Science and Technology 35, 4495-4501.
Pilinis, C., 1989. Numerical Simulation of Visibility Degradation Due to Particulate Matter: Model Development and Evaluation. Journal of Geophysical Research 94, 9937-9946.
Pitt, J.N., Grosjean Jr., D., Van, C.K., Schmid, J.P., Fitz, D.R., 1978. Photooxidation of aliphatic amines under simulated atmospheric conditions: formation of nitrosamines. nitramines. amides and photochemical oxidant. Environmental Science and Technology 12, 946-953.
Rogge, W.F., Mazurek, M.A., Hildemann, L.M., Cass, G.R., Simoneit, B.R.T., 1993a. Sources of Fine Organic Aerosol. 4. Particulate Abrasion Products from Leaf Surfaces of Urban Plants. Environmental Science and Technology 27, 2700-2711.
Rogge, W.F., Mazurek, M.A., Hildemann, L.M., Cass, G.R., 1993b. Quantification of Urban Organic Aerosols at a Molecular Level: Identification, Abundance and Seasonal Variation. Atomspheric Environment 27, 1309-1330.
Rood, M.J., Shaw, M.A., Larson, T.V., 1989. Ubiquitous nature of ambient metastable aerosol. Nature 337, 537-539.
Saxena, P., Hidemann, L. M., McMurry, P. H., Seinfeld, J. H., 1995. Organics alter hygroscopic behavior of atmosphere particles. Journal of Geophysical Research 100, 18755-18770.
Saxena, P., Hildemann, L.M., 1996. Water-soluble organic atmospheric particles: A critical review of the literature and application of thermodynamics to identify candidate compounds. Journal of Atmospheric Chemistry 24, 57-109.
Seinfeld, J.H., Pandis, S.N., 1998. Atmospheric Chemistry and Physics. John Wiley, New York.
Sempere, R., Kawamura, K., 1994. Comparative distributions of dicarboxylic acids and related polar compounds in snow, rain and aerosols from urban atmosphere. Atmospheric Environment 28, 449-459.
Solane, C.S., 1983. Optical properties of aerosol-composition of measurements with model calculations. Atmospheric Environment 17, 409-416.
Tabazadeh, A., Jensen, E.J., Toon, O.B., 1997. A model descruption for cirrus cloud nucleation from homogeneous freezing of sulfate aerosols. Journal of Geophysical Research 102, 23845-23850.
Talbot, R.W., Dibb, J.E., Loomis, M.B., 1998. Influence of vertical transport on free tropospheric aerosols over the central USA in springtime. Geophysical Research Letter 25, 1367-1370.
Tang, I.N., Fung, K.H., Imre, D.G., Munkelwitz, H.R., 1995. Phase transformation and metastability of hygroscopic microparticles. Aerosol Science and Technology 23, 443-453.
Tang, I.N., 1980. Deliquescence properties and particle size change of hygroscopic aerosols. In generation of aerosols and facilities for exposure experiments (edited by Willeke, K.), 153-167. Ann Arbor Science, Ann Arbor, MI.
Tang, I.N., 1997. Thermodynamic and optical properties of mixed-salt aerosols of atmospheric importance. Journal of Geophysical Research 102, 1883-1893.
Tuch, A. M., Tamm, E.J., Heyder, H.P., Brand, C.H., Roth, H.E., Wichmann, J.P., Kreyling, W.G., 2000. Comparsion of two partical-size spectrometers for ambient aerosol measurements. Atmospheric Environment 34, 139-149.
U.S.EPA, 1999. Visibility Monitoring Guidance. Research Triangle Park. EPA-454/R-99-003.
Wexler, A.S., Seinfeld, J.H., 1991. Second-generation inorganic aerosol model.
Zhuang, H., Chan, C.K., Fang, M., Wexler, A.S., 1999a. Formation of nitrate and non-sea-salt sulfate on coarse particles. Atmospheric Environment 33, 4223-4233.
Zhuang, H., Chan, C.K., Fang, M., Wexler, A.S., 1999b. Size distributions of particulate sulfate, nitrate and ammonium at a coastal site in Hong Kong. Atmospheric Environment 33, 843-853.
Zheng, B., Sage, M., Cai, W.W., Thompson, D.M., Tavsanli, B.C., Cheah, Y.C., Bradley, A., 1999. Engineering a mouse balancer chromosome. Nat Grent 22(4), 375-378.
張士昱，2001。易潮解無機氣膠含水特性之研究。國立中央大學環境工程研究所博士論文。
李慧梅，1997。有機物影響下大氣氣膠潮解現象之研究。國科會研究報告NSC86-2211-E-002-012。
蔡德明、吳義林，2000。相對溼度對質量濃度之影響效應研究。第十七屆空氣污染控制技術研討會論文集，126-131。
簡弘民、李壽南，2000。監測站PM10、PM2.5量測比較及污染源分析。第八屆氣膠科技研討會論文集，22-28。
顏有利、李康文、許志雄，1998。竹山測站附近PM10污染源之調查及其影響之探討(Ⅱ)。南投縣環保局。
顏有利、王竹方、江鴻龍，2000。竹山測站、南投測站及埔里測站附近PM10污染源之調查。南投縣環保局。
黃明雄，1997。台灣地區大氣氣膠特性之研究-墾丁氣膠組成及濃度對大氣能見度的影響。國立中央大學環境工程研究所碩士論文。