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K Selvam

Publications and source records attributed to K Selvam.

5 recordsLinked to original sources
PubMed2006

A comparative study of quantum yield and electrical energy per order (E(Eo)) for advanced oxidative decolourisation of reactive azo dyes by UV light.

This paper evaluates the quantum yield and electrical energy per order (E(Eo)) efficiency of Reactive Orange 4 (RO4) and Reactive Yellow 14 (RY14) azo dyes by three advanced oxidation processes (AOPs). Both dyes were completely decolourised by all these processes. The relative decolourisation efficiencies of these processes were in the following order: Fe(2+)/H(2)O(2)/UV>UV/TiO(2)>UV/H(2)O(2). The low efficiency of UV/H(2)O(2) process is mainly due to low UV absorption by hydrogen peroxide at the 365nm. The figure of merit E(Eo) values showed that UV/H(2)O(2) process consumes more electrical energy than the other two processes. The electrical energy consumption is in the following order: UV/H(2)O(2)>UV/TiO(2)>Fe(2+)/H(2)O(2)/UV. At low initial dye concentration higher quantum yield was observed in UV/TiO(2) process, whereas in photo-Fenton process higher quantum yield was observed at high initial dye concentration. The structure of dye molecule also influences the quantum yield and E(Eo) value.

Azo Compounds↗
PubMed2003

Decolourization of azo dyes and a dye industry effluent by a white rot fungus Thelephora sp.

A white rot fungus Thelephora sp. was used for decolourization of azo dyes such as orange G (50 microM), congo red (50 microM), and amido black 10B (25 microM). Decolourization using the fungus was 33.3%, 97.1% and 98.8% for orange G, congo red and amido black 10B, respectively. An enzymatic dye decolourization study showed that a maximum of 19% orange G was removed by laccase at 15 U/ml whereas lignin peroxidase (LiP) and manganese dependent peroxidase (MnP) at the same concentration decolourized 13.5% and 10.8%, orange G, respectively. A maximum decolourization of 12.0% and 15.0% for congo red and amido black 10B, respectively, was recorded by laccase. A dye industry effluent was treated by the fungus in batch and continuous modes. A maximum decolourization of 61% was achieved on the third day in the batch mode and a maximum decolourization of 50% was obtained by the seventh day in the continuous mode. These results suggest that the batch mode of treatment using Thelephora sp. may be more effective than the continuous mode for colour removal from dye industry effluents.

Azo Compounds↗
PubMed2001

The Saddle prosthesis in periacetabular tumours.

The Saddle endoprosthesis provides a means of establishing a stable and mobile articulation between the femur and a partially resected pelvis. Six patients with malignant or aggressive benign bone tumours underwent resection and replacement with custom-made Saddle endoprosthesis. Wide margin was achieved in four cases and marginal margin in two. Follow-up ranged from 24 to 41 months. All the six patients were then alive, five being disease-free. One patient developed deep infection and local recurrence necessitating removal of the prosthesis. The functional results were either excellent or good in five patients.

Acetabulum↗
PubMedDate not supplied

Isolated congenital left ventricular diverticulum in adults.

Isolated congenital ventricular diverticulum or aneurysm is rare and usually arises from the left ventricle. The presentation of this condition is diverse. We report three cases of isolated congenital left ventricular diverticula. The age range was 17-30 years. Chest X-ray provided the earliest clinical suspicion in these three cases of a cardiac anomaly which was diagnosed by echocardiography and confirmed by angiocardiography. The location of the congenital left ventricular diverticulum was the left ventricular apex in two cases and basal in the other. We conclude that congenital left ventricular diverticulum is a disease of protean presentations. A high index of suspicion is necessary while interpreting chest X-rays and echocardiographs to diagnose congenital left ventricular diverticulum. A contractile accessory chamber of the left ventricle with a narrow neck with or without midline defects and an electrocardiogram without Q waves is consistent with the diagnosis of congenital left ventricular diverticulum.

Adolescent↗