scholarly journals Time-Resolved ESR Study on Complex Radical Pairs Formed in the Photolysis of Methylene Blue Included in Water-Soluble Sulfonated Calixarenes

2009 ◽  
Vol 37 (1-4) ◽  
pp. 581-593 ◽  
Author(s):  
Akiko Tanaka ◽  
Haruhiko Yashiro ◽  
Asako Ishigaki ◽  
Hisao Murai
Keyword(s):  
Methylene Blue ◽  
Water Soluble ◽  
Radical Pairs ◽  
Time Resolved ◽  
Sulfonated Calixarenes

scholarly journals Sulfobetaine Cryogels for Preferential Adsorption of Methyl Orange from Mixed Dye Solutions

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 208
Author(s):  
Ramona B. J. Ihlenburg ◽  
Anne-Catherine Lehnen ◽  
Joachim Koetz ◽  
Andreas Taubert
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Methyl Orange ◽  
Dye Removal ◽  
Selective Adsorption ◽  
Water Soluble ◽  
Organic Substances ◽  
Preferential Adsorption ◽  
Dimethyl Ammonium ◽  
Dye Solutions

New cryogels for selective dye removal from aqueous solution were prepared by free radical polymerization from the highly water-soluble crosslinker N,N,N’,N’-tetramethyl-N,N’-bis(2-ethylmethacrylate)-propyl-1,3-diammonium dibromide and the sulfobetaine monomer 2-(N-3-sulfopropyl-N,N-dimethyl ammonium)ethyl methacrylate. The resulting white and opaque cryogels have micrometer sized pores with a smaller substructure. They adsorb methyl orange (MO) but not methylene blue (MB) from aqueous solution. Mixtures of MO and MB can be separated through selective adsorption of the MO to the cryogels while the MB remains in solution. The resulting cryogels are thus candidates for the removal of hazardous organic substances, as exemplified by MO and MB, from water. Clearly, it is possible that the cryogels are also potentially interesting for removal of other compounds such as pharmaceuticals or pesticides, but this must be investigated further.

scholarly journals Ion Mobility Spectrometry-Mass Spectrometry (IMS-MS) for on- and off-line analysis of atmospheric gas and aerosol species

2016 ◽  
Author(s):  
Jordan E. Krechmer ◽  
Michael Groessl ◽  
Xuan Zhang ◽  
Heikki Junninen ◽  
Paola Massoli ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Ion Mobility Spectrometry ◽  
Ion Mobility ◽  
Measurement Techniques ◽  
Molecular Ions ◽  
Molecular Structures ◽  
Water Soluble ◽  
Oxidation Products ◽  
Time Resolved ◽  
Organic Species

Abstract. Measurement techniques that provide molecular-level information are needed to elucidate the multi-phase processes that produce secondary organic aerosol (SOA) species in the atmosphere. Here we demonstrate the application of ion mobility spectrometry-mass spectrometry (IMS-MS) to the simultaneous characterization of the elemental composition and molecular structures of organic species in the gas and particulate phases. Molecular ions of gas-phase organic species are measured online with IMS-MS after ionization with a custom build nitrate chemical ionization (CI) source. This CI-IMS-MS technique is used to obtain time-resolved measurements (5 min) of highly oxidized organic molecules during the 2013 Southern Oxidant and Aerosol Study (SOAS) ambient field campaign in the forested SE US. The ambient IMS-MS signals are consistent with laboratory IMS-MS spectra obtained from single-component carboxylic acids and multicomponent mixtures of isoprene and monoterpene oxidation products. Mass-mobility correlations in the 2-dimensional IMS-MS space provide a means of identifying ions with similar molecular structures within complex mass spectra and are used to separate and identify monoterpene oxidation products in the ambient data that are produced from different chemical pathways. Water-soluble organic carbon (WSOC) constituents of fine aerosol particles that are not resolvable with standard analytical separation methods, such as liquid chromatography (LC), are shown to be separable with IMS-MS coupled to an electrospray ionization (ESI) source. The capability to use ion mobility to differentiate between isomers is demonstrated for organosulfates derived from the reactive uptake of isomers of isoprene epoxydiols (IEPOX) onto wet acidic sulfate aerosol. Controlled fragmentation of precursor ions by collisional dissociation (CID) in the transfer region between the IMS and the MS is used to validate MS peak assignments, elucidate structures of oligomers, and confirm the presence of the organosulfate functional group.

scholarly journals Chemical characterisation of water-soluble ions in atmospheric particulate matter on the east coast of Peninsular Malaysia

2019 ◽  
Vol 19 (3) ◽  
pp. 1537-1553 ◽  
Author(s):  
Naomi J. Farren ◽  
Rachel E. Dunmore ◽  
Mohammed Iqbal Mead ◽  
Mohd Shahrul Mohd Nadzir ◽  
Azizan Abu Samah ◽  
...  
Keyword(s):  
South China Sea ◽  
East Asia ◽  
East Coast ◽  
Peninsular Malaysia ◽  
Water Soluble ◽  
Time Resolved ◽  
Air Masses ◽  
Soluble Ions ◽  
Water Soluble Ions ◽  
Marine Air

Abstract. Air quality on the east coast of Peninsular Malaysia is influenced by local anthropogenic and biogenic emissions as well as marine air masses from the South China Sea and aged emissions transported from highly polluted East Asian regions during the winter monsoon season. An atmospheric observation tower has been constructed on this coastline at the Bachok Marine Research Station. Daily PM2.5 samples were collected from the top of the observation tower over a 3-week period, and ion chromatography was used to make time-resolved measurements of major atmospheric ions present in aerosol. SO42- was found to be the most dominant ion present and on average made up 66 % of the total ion content. Predictions of aerosol pH were made using the ISORROPIA II thermodynamic model, and it was estimated that the aerosol was highly acidic, with pH values ranging from −0.97 to 1.12. A clear difference in aerosol composition was found between continental air masses originating from industrialised regions of East Asia and marine air masses predominantly influenced by the South China Sea. For example, elevated SO42- concentrations and increased Cl− depletion were observed when continental air masses that had passed over highly industrialised regions of East Asia arrived at the measurement site. Correlation analyses of the ionic species and assessment of ratios between different ions provided an insight into common sources and formation pathways of key atmospheric ions, such as SO42-, NH4+ and C2O42-. To our knowledge, time-resolved measurements of water-soluble ions in PM2.5 are virtually non-existent in rural locations on the east coast of Peninsular Malaysia. Overall this dataset contributes towards a better understanding of atmospheric composition in the Maritime Continent, a region of the tropics that is vulnerable to the effects of poor air quality, largely as a result of rapid industrialisation in East Asia.

ChemInform Abstract: TIME-RESOLVED LASER FLASH SPECTROSCOPIC STUDY OF BENZYL RADICAL PAIRS IN MICELLE CAGES

1981 ◽  
Vol 12 (44) ◽  
Author(s):  
N. J. TURRO ◽  
M.-F. CHOW ◽  
C.-J. CHUNG ◽  
Y. TANIMOTO ◽  
G. C. WEED
Keyword(s):  
Spectroscopic Study ◽  
Laser Flash ◽  
Radical Pairs ◽  
Time Resolved ◽  
Benzyl Radical

Excitation energy transfer in a cationic water-soluble conjugated co-polymer studied by time resolved anisotropy and fluorescence dynamics

2006 ◽  
Vol 421 (1-3) ◽  
pp. 205-209 ◽  
Author(s):  
D. Anestopoulos ◽  
M. Fakis ◽  
P. Persephonis ◽  
V. Giannetas ◽  
J. Mikroyannidis
Keyword(s):  
Energy Transfer ◽  
Excitation Energy ◽  
Excitation Energy Transfer ◽  
Water Soluble ◽  
Time Resolved
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