Multiple Effect of pH on Photocatalytic Degradation of Orange II Using TiO2

2010 ◽  
Vol 113-116 ◽  
pp. 1878-1883
Author(s):  
Guo Ting Li ◽  
Fa Zhan Li ◽  
Pei Yong Zhang ◽  
Yun Xia Li ◽  
Chao Yuan

The performance of UV/TiO2 (100 mg/L TiO2) process for Orange II degrdation was emphatically compared at pH 2.3, 6.9 and 11.5 by means of UV-Visible spectra, ionic chromatography, TOC, and HPLC analyses. The results revealed that the reaction intermediates were produced in different contents with the increasing reaction time due to the different pH conditions. The dye was oxidized more completely at pH 2.3 while the highest color removal percentage was achieved at pH 11.5. It was proved that active electrons, which is photo-generated along with positive holes on TiO2, not only contribute to the discoloration and mineralization of the dye due to the producing of oxidative species such as O2•- and •OOH, but also contribute to the discoloration of Orange II as reductive species. The most possible mechanism was put forward to explain the key roles of active electrons in dye degradation by UV/TiO2 process at pH 2.3 and 11.5.

1977 ◽  
Vol 38 (10) ◽  
pp. 1293-1299 ◽  
Author(s):  
U. Giorgianni ◽  
G. Mondio ◽  
P. Perillo ◽  
G. Saitta ◽  
G. Vermiglio
Keyword(s):  

2016 ◽  
Vol 20 (07) ◽  
pp. 753-765 ◽  
Author(s):  
Lina Ye ◽  
Zhongping Ou ◽  
Yuanyuan Fang ◽  
Yang Song ◽  
Bihong Li ◽  
...  

Three copper triarylcorroles containing a [Formula: see text]-pyrrole nitro substituent were synthesized and characterized as to their spectral and electrochemical properties in nonaqueous media. The examined compounds are represented as [Formula: see text]-NO2(YPh)3CorCu, where Cor is the trianion of a triphenylcorrole and Y is a Cl, H or CH3 substituent at the para-position of the three meso-phenyl rings of the compound. The data from absorption spectra, electrochemistry and thin-layer spectroelectrochemistry are consistent with an initial assignment of Cu[Formula: see text]-Cor[Formula: see text] in CH2Cl2, DMF and pyridine and electrogeneration of a formal Cu(II) corrole with an unreduced macrocycle, represented as Cu[Formula: see text]-Cor[Formula: see text], after the first one-electron reduction in these solvents. The doubly reduced [Formula: see text]-nitrocorrole has a sharp Soret band at 439 nm and a well-defined Q-band at 611 nm in CH2Cl2. Similar absorption spectra are seen for the three examined doubly reduced nitrocorroles in DMF and pyridine, suggesting formation of a Cu(I) species with an unreduced macrocycle which is represented as Cu[Formula: see text]-Cor[Formula: see text]. Changes in redox potentials and absorption spectra of the nitrocorroles are examined as a function of solvent and substituents on the meso-phenyl rings of the compounds and comparisons are made between spectral and electrochemical data of the newly synthesized corroles and that of structurally related tetraarylcorroles lacking a [Formula: see text]-nitro group.


2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Amali Subasinghe ◽  
Inoka C. Perera ◽  
Svetlana Pakhomova ◽  
Theshini Perera

A novel ligand bearing a central piperidinyl sulfonamide group, N(SO2pip)dpa, and its corresponding Re tricarbonyl complex, [Re(CO)3(N(SO2pip)dpa)]+, have been synthesized in good yield. The methylene CH2signal seen as a singlet (4.54 ppm) in a1H NMR spectrum of the ligand in DMSO-d6appears as two doublets (5.39, 5.01 ppm) in a spectrum of the [Re(CO)3(N(SO2pip)dpa)]+complex and confirms the presence of magnetically nonequivalent protons upon coordination to Re. Structural results revealed that the Re–N bond lengths fall within the normal range establishing coordination of ligand to metal. The presence of intraligandπ→π⁎andn→π⁎transitions is indicated by the absorption peaks around 200–250 nm in UV-visible spectra. Absorption peaks in UV-visible spectra around 300 nm for metal complexes were identified as MLCT transitions. The S–N stretch observed as a strong peak at 923 cm−1for N(SO2pip)dpa appeared at a shorter frequency, at 830 cm−1in an FTIR spectrum of the [Re(CO)3(N(SO2pip)dpa)]+. The intense fluorescence displayed by the N(SO2pip)dpa ligand has quenched upon coordination to Re. Relatively low IC50values given by human breast cancer cells, MCF-7, (N(SO2pip)dpa = 139 μM, [Re(CO)3(N(SO2pip)dpa)]+= 360 μM) indicate that N(SO2pip)dpa and [Re(CO)3(N(SO2pip)dpa)]+are promising novel compounds that can be further investigated on their usage as potential anticancer agents.


2014 ◽  
Vol 3 (2) ◽  
pp. 85-96 ◽  
Author(s):  
Nader Noroozi Pesyan ◽  
Sadeghali Bavafa ◽  
Mohammad Samim Enayati ◽  
Sajedin Hoseinpour ◽  
Narges Ostadhosseini ◽  
...  
Keyword(s):  
X Ray ◽  

Author(s):  
Nivetha Govindaraj ◽  
Sheeana Gangadoo ◽  
Vi Khanh Truong ◽  
James Chapman ◽  
Harsharn Gill ◽  
...  
Keyword(s):  

2016 ◽  
Vol 120 (40) ◽  
pp. 10547-10552 ◽  
Author(s):  
Fereshteh Samiee ◽  
Federico N. Pedron ◽  
Dario A. Estrin ◽  
Liliana Trevani

2019 ◽  
Vol 17 (72) ◽  
pp. 129-138
Author(s):  
Yasmine Kadom. Al-Majedy

Novel Quinozolins were synthesized in a good yield through convert lacton to lactam and study the biological activity of the synthesized compounds. Quinozolins were characterized by elemental analysis, FT-IR and UV/visible spectra. The novel Quinozolins have been tested in vitro against (gram positive bacteria Staphylococcus aureus and against other gram negative bacteria, such as Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Proteus vulgaris; in order to assess their antimicrobial properties. Moreover, charge, bond length, bond angle, twist angle, heat of formation and steric energy were calculated by using of the ChemOffice program. The study indicates that these Quinozolins have high activity against tested bacteria. Based on the reported results, it may be concluded that the coumarin act as synthons for synthesis of new Quinozolins derivatives through the replacement of oxygen atom by nitrogen atom.


2011 ◽  
Vol 8 (4) ◽  
pp. 1005-1011
Author(s):  
Baghdad Science Journal

Many complexes of 3,5-dimethyl-1H-pyrazol-1-yl phenyl methanone with Cr(III), Co(II), Ni(II), Cu(II) and Cd(II) were synthesized and characterized by FT-IR, UV/visible spectra, elemental analysis, room temperature magnetic susceptibility and molar conductivity. Cd(II) complex was expected to have tetrahedral structure while all the other complexes were expected to have an octahedral structure.


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