An experimental investigation of the concentration dependence of electrokinetic transport coefficients of methanol + ethanol mixtures through a quartz plug is described. Electro-osmotic flow and streaming-potential measurements have been carried out. The Onsager reciprocity relations have been experimentally checked for all compositions of the binary mixture used. The form of the fluidity curve indicates that the ethanol+methanol mixture is a quasi-ideal system with a small negative deviation. The hydrodynamic permeability of systems comprising methanol+ethanol mixtures and a porous plug and the fluidity of the mixture vary with the composition in a similar way. The variation of the cross-phenomenological coefficient with composition is due to an analogous variation of the term Dc/r,~ with the mole fraction of methanol. On the other hand, the ratio of streaming potential to pressure difference (in the interval 0-20cmHg) decreases as the pressure drop increases. This result agrees with the theoretical findings of Rutgers and Boumans concerning the effect of turbulence on the streaming potential. The concentration dependence of the second-order coefficients has been partially explained on the basis of Jha's equations.

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Data on the adsorption of tannic acid on the hydrophilic cotton a t different temperatures arc presented. The thermodynamics of the adsorption equilibria of tannic acid is investigated, and it is established that the increase in temperature decreases the amount of tannic acid adsorbed. The adsorption equilibria of tannic acid are described by the FREUND-LICH adsorption isotherm. Also, an experimental investigation on streaming potentials of cellulose/tannic acid/Rhodamine B solutions system is described and the effect of the mordant on the electrokinetic properties of cellulosic fibres dyed with a cationic dye is analyzed. The behaviour of the electrokinetic potential could be explained mainly by the H-bonds formed between the phenolic hydroxy groups of tannic acid and the carboxy groups of cellulose and by the electrostatic attraction between the dye cation and the surface of the fibre. Die Adsorption von Tannin a n hydrophiler Baurnwollt! und ihr Einflup auf die elektrokinetischen Eigenschaften der Cellulosefasern in einer kationischen FarbstofflosungMefiergebnisse zur Adsorption von Tannin auf hydrophiler Baumwolle bei unterschiedlichen Temperaturen werden vorgestellt. Die Thermodynamik des Adsorptionsgleichgewichtes des Tannins wird untersucht. Mit zunehmender Temperatur nimmt die Menge des adsorbierten Tannins ab. Das Adsorptionsgleichgewicht des Tannins lafit sich durch eine Adsorptionsisotherme nach FREUNDLICH beschreiben. Weiterhin wurde das Stromungspotential des Systems Cellulose/Tannin/Rhodamin-B-Losung untersucht, und der EinfluB der Beize auf die clektrokinetischen Eigenschaften der mit einem kationischen Farbstoff gefarbten Cellulosefasern wurde analysiert. Das Verhalten des elektrokinetischen Potentials konnte im wesentlichen durch die Bildung von H-Brucken zwischen den phenolischen Hydroxylgruppen dcs Tannins und den Carboxygruppen der Cellulose sowie durch die elektrostatisclie Anziehung zwischen dem Farbstoff-Kation und der Faseroberflache erklart werden. A&op6tpa mannuna zuapo@ubnb&a xnonKoM u ee sfiuxnue Ha aneicmpo~unemuuec~ue csoiicmsa yefimono3nbax sofio-Eon s pacmsope Kamuonnbax I;pacumeaefi kl3yqeHa agcop6qna TaHHHHa rHApO@HJIbHbIM XJIOIIKOM IIpH pa3JIMqHbIX TeMIlepaTypaX, a TaKWe TepMOgHHaMHKa paBHOBeCHR a~c o p 6 q m TaHHHHa. YCTaHOBJIeHo, 41'0 KOJIHZIeCTBO aACOp6HpyeMOrO T a H H H H a yMeHbUIaeTCR C yBenH-YeHMeM TeMlIepaTypbI. A~COp6qHOHHOe PaBHOBeCHe MOWHO OnIICbIBaTb agCOp6qHOHHOfi M30TepMOii no ( D P E~~H~J I H X Y . KpOMe TOP0 H3yqeH IIOTeHUHaJl IIOTOKa B CHCTeMe UenJlIoJIO3a-TaHHIIM-paCTBOp pOAaMIIHa 6 II npoBegeH a~aa113 BJIARHHR IIpOTpaBbI H a 3JIeKTpOKHHeTHZIeCKHe CBOfiCTBa IJeJIJIIOJIO3HbIX BOJIOKOH, OKpalUeHHbIX KaTHOHHbIM KpaCH-TeJIeM. kl3MeHeHHR 3JIeKTPOKHHeTHYeCKOrO IIOTeHUHaJIa MOWHO O6'bRCHHTb, B OCHOBHOM, 06pa30BaHMeM BOgOpOA-HbIX CBH3efi MeWgy (PeH0JIbHbIM.R rHApoKCMJIbHbIMm rpynnaMH T a H H A H a H KaP6OKCHnbHbIMH rpynnaMH qexnmno3b1, a TaKWe 3JIeKTpOCTaTH' IeCKHM IIpIITHHteHHeM MeWBy KaTHOHHbIM KpaCIITeJIeM H IIOBepXHOCTbH, BOJIOKHB.

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An experimental investigation of electroosmosis for the nonlinear region is described. Porous diaphragms of pyrex glass particles, whose diameters were in the range 150-500 μιη, and methyl-, ethyl-, and iso-propyl alcohols have been used to perform the electroosmotic experiments. The phenomenological coefficient L m was found to be non-significant at the 95% confidence level. The electroosmotic flux dependence on ΔΦ for the pyrex-ethanol system in the non-linear range is opposed to that of the pyrex-methanol system. The contribution of the L 112 coefficient had a significant value only when ethyl-alcohol was employed as a permeant. Its sign changes from positive to negative when the thickness of the porous diaphragm is lowered below 1.50 cm. For pyrex-ethanol systems, the L 122 phenomenological coefficient was found to be independent on the thickness of the plug and its absolute value to increase when the size of the particles of the plug was decreased. For pyrex-methanol systems, there seems to be no dependence of the above coefficient on the size of the particles forming the plug. Furthermore, L 122 increases its value when the thickness of the plug is diminished. When iso-propyl alcohol was employed as a permeant, linearity was observed up to ΔΦ equal to 900 V.