Aqueous solutions of lower alcohols investigated by pyrene fluorescence spectroscopy.

The aqueous solutions of lower alcohols such as methanol, ethanol, 1-propanol and 2-propanol, were studied by fluorescence spectroscopy of pyrene, defining the Py scale for polarity. Sigmoidal curves were used to fit the Py values of aqueous alcohol solutions as a function of the logarithm of water-alcohol mole ratio, i.e.

Micro-Raman and FTIR spectroscopic observation on the phase transitions of MnSO4 droplets and ionic interactions between Mn2+ and SO4(2-).

Micro-Raman and FTIR spectroscopy have been used to investigate the micrometer-sized MnSO(4) droplets. The concentration of solute within the droplet is controlled accurately by decreasing the relative humidity (RH) of the surroundings. According to the Raman spectra of MnSO(4) droplets, when the RH decreased from approximately 94% to approximately 76%, the full width of the peak at half-maximum (fwhm) of the v(1)-SO(4)(2-) band at 983 cm(-1) initially increased from 95.

[Confocal Raman study on ZnSO4 droplets in the efflorescence process].

Confocal Raman technique was used to investigate the structure changes of the ZnSO4 droplets deposited on Teflon substrate in the efflorescence process at the molecular level. Upon decreasing the relative humidity (RH), the symmetric stretching band (upsilon1-SO4(2-)) of ZnSO4 droplet blue shifted from 981 cm(-1) gradually to 987, 998 and 1,008 cm(-1), respectively, indicating that the free SO4(2-) ion associates with Zn2+ ion as the solution concentration increases and forms various contact ion pairs (CIPs), i. e.

Spatially resolved micro-Raman observation on the phase separation of effloresced sea salt droplets.

We report on the investigation of the phase separation of individual seawater droplets in the efflorescence processes with the spatially resolved Raman system. Upon decreasing the relative humidity (RH), CaSO4.0.

Confocal Raman studies of Mg(NO3)2 aerosol particles deposited on a quartz substrate: supersaturated structures and complicated phase transitions.

Individual Mg(NO3)2 aerosol particles deposited on a quartz substrate were investigated by confocal Raman spectroscopy. With decreasing the relative humidity (RH) from 92.0% to 1.

Raman observation of the interactions between NH4+, SO4(2-), and H2O in supersaturated (NH4)2SO4 droplets.

High signal-to-noise ratio (S/N) Raman spectra of (NH(4))(2)SO(4) droplets deposited on a quartz substrate were obtained from dilute to supersaturated states upon decreasing the relative humidity (RH). When the molar water-to-solute ratio (WSR) decreases from 16.8 to 3.