Determination of total carbonyl compounds in aqueous media

1993 ◽  
Vol 70 (9) ◽  
pp. 881-884 ◽  
Author(s):  
Natsuko Yukawa ◽  
Hitoshi Takamura ◽  
Teruyoshi Matoba
Keyword(s):  
Carbonyl Compounds ◽  
Aqueous Media ◽  
Total Carbonyl

Dissociation of imino proton(s) of a highly water-soluble metal-free phthalocyanine and determination of its pKa value in water

2013 ◽  
Vol 17 (06n07) ◽  
pp. 447-453 ◽  
Author(s):  
Hiroaki Isago ◽  
Harumi Fujita
Keyword(s):  
Aqueous Media ◽  
Thermal Reaction ◽  
Water Soluble ◽  
Acid Dissociation ◽  
Acid Dissociation Constant ◽  
Metal Free ◽  
Imino Proton ◽  
Pka Value ◽  
Triton X

Dissociation of imino proton(s) in the cavity of the macrocycle of a highly water-soluble, metal-free phthalocyanine ( H 2( H 4 tsppc ); where H 4 tsppc denotes tetrakis{(2′,6′-dimethyl-4′-sulfonic acid)phenoxy}phthalocyaninate) in ethanolic and aqueous solutions has spectrophotometrically been investigated. The spectral changes associated with reaction with NaOH have been found to involve one-proton transfer process in aqueous media while two-protons process in ethanolic media. The acid-dissociation constant of the first imino proton in water (in the presence of Triton X-100) has been determined to be 12.5 ± 0.2 (as pKa) at 25 °C. The doubly deprotonated species in EtOH has been easily converted to its corresponding cobalt(II) derivative by thermal reaction with anhydrous CoCl 2.

Enzymic Determination of Peroxides in Non-aqueous Media

The Analyst ◽  
1997 ◽  
Vol 122 (12) ◽  
pp. 1543-1547 ◽  
Author(s):  
Gerardo Piñeiro Avila ◽  
Miguel de la Guardia
Keyword(s):  
Aqueous Media

Extraction-atomic-absorption spectrophotometric determination of antimony by generation of its hydride in non-aqueous media

The Analyst ◽  
1984 ◽  
Vol 109 (2) ◽  
pp. 123-125 ◽  
Author(s):  
José Aznárez ◽  
Francisco Palacios ◽  
Maria S. Ortega ◽  
Juan Carlos Vidal
Keyword(s):  
Atomic Absorption ◽  
Spectrophotometric Determination ◽  
Aqueous Media

Two-photon excited fluorescent chemosensor for homogeneous determination of copper(ii) in aqueous media and complicated biological matrix

The Analyst ◽  
2011 ◽  
Vol 136 (10) ◽  
pp. 2139 ◽  
Author(s):  
Lingzhi Liu ◽  
Xiaohu Dong ◽  
Yan Xiao ◽  
Wenlong Lian ◽  
Zhihong Liu
Keyword(s):  
Aqueous Media ◽  
Fluorescent Chemosensor ◽  
Biological Matrix ◽  
Two Photon ◽  
Determination Of Copper

Free-base corroles: determination of deprotonation constants in non-aqueous media

2007 ◽  
Vol 11 (04) ◽  
pp. 269-276 ◽  
Author(s):  
Jing Shen ◽  
Zhongping Ou ◽  
Jianguo Shao ◽  
Michał Gałęzowski ◽  
Daniel T. Gryko ◽  
...  
Keyword(s):  
Equilibrium Constants ◽  
Aqueous Media ◽  
Free Base ◽  
Organic Base ◽  
Experimental Conditions ◽  
Spectral Changes ◽  
Base Analysis ◽  
Uv Visible ◽  
The Given

A series of free-base corroles with different electron-donating or electron-withdrawing substituents were reacted with piperidine, 4-aminopyridine, 2-methylimidazole, 2-aminopyridine or pyridine in PhCN and the UV-visible spectral changes monitored during conversion of ( Cor ) H 3 to [( Cor ) H 2]- as a function of the concentration and strength of the added organic base. Analysis of the UV-visible spectral changes as a function of the added base concentration enabled calculation of equilibrium constants ( logK ) for deprotonation of each corrole under the given experimental conditions. Relationships are examined between the experimentally measured logK values and previously published spectroscopic and structural properties of the compounds.

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