Activated carbon catalyzed persulfate oxidation of Azo dye acid orange 7 at ambient temperature.

Organic dyes are one of the largest groups of pollutants discharged into wastewaters from textile and other industrial processes. Owing to the potential toxicity of the dyes and their visibility in surface waters, removal and degradation of them have attracted considerable attention worldwide. A wide range of approaches have been developed, amongst which the heterogeneous photocatalysis involving zinc oxide (ZnO) emerges as a promising new route for water purification process. For the first time, we attempt to review and summarize the recent research on ZnO photocatalytic systems for organic dyes degradation. The photocatalysis on modified ZnO is also discussed, in particular aiming at enhancing the degradation efficiency and activity in visible region as well as solar irradiation. The effects of key operational parameters on the photocatalytic performance in terms of the degradation and mineralization of dyes are detailed. This review also highlights the utilization of multivariate analysis to d...

Degradation of wastewaters containing organic dyes photocatalysed by zinc oxide: a review

An analytical technique using the `Newton-Raphson' method is presented to identify the saturated magnetising reactance and the generated frequency of a self-excited induction generator for a given capacitance, speed and load. The technique is shown to be very efficient in analysing such systems under steady state. Computed results are compared with the experimentally obtained values on a laboratory machine, and a reasonable correlation has been observed. Effects of various system parameters on the steady-state performance have been studied, and the results presented provide guidelines for optimum design of such systems.

Analysis of self-excited induction generators

Recent advances in photocatalytic treatment of pollutants in aqueous media.

Tetrabromobisphenol A (TBBPA) is the most widely used brominated flame retardant around the world. In the present study, for the first time we explored the photocatalytic oxidation of TBBPA by nanoarchitectural BiOBr microspheres. BiOBr photocatalysts were synthesized via solvothermal method with various preparation conditions, and the optimal synthesis condition was determined according to their characterization results and rhodamine B (RhB) removal efficiencies. The prepared optimal BiOBr was mesoporous material of pure tetragonal phase, which removed nearly 100% of RhB from solution after 60 min simulated solar light irradiation. The BiOBr was adopted to decompose TBBPA, which was almost totally eliminated after 15 min in the UV–vis/BiOBr system. The kinetic analysis indicated that the reaction rate constants were 0.388 and 0.101 min−1 for BiOBr and P25 TiO2, respectively, suggesting that BiOBr effectively and kinetically enhanced the decomposition of TBBPA. Eight major reaction products or intermediates were identified by HPLC–MS and HPLC–SIR–MS, and a tentative degradation pathway of TBBPA was proposed. The mechanism originally illustrated that both hydroxylation and debromination played important roles in TBBPA transformation. The exceptional efficiency of mesoporous BiOBr in removing TBBPA represents a promising technique for treatment of TBBPA-containing wastewater or remediation of TBBPA-contaminated environmental matrices.

Photocatalytic degradation of tetrabromobisphenol A by mesoporous BiOBr: Efficacy, products and pathway

Photocatalytic degradation of azo dye in aqueous TiO2 suspension: Reaction pathway and identification of intermediates products by LC/MS

Pneumonia is an infection that causes inflammation of lungs and can be deadly if not detected on time. The commonly used method to detect Pneumonia is using chest X-ray which requires careful examination of chest X-ray images by an expert. The method of detecting pneumonia using chest X-ray images by an expert is time-consuming and less accurate. In this paper, we propose different deep convolution neural network (CNN) architectures to extract features from images of chest X-ray and classify the images to detect if a person has pneumonia. To evaluate the effect of dataset size on the performance of CNN, we train the proposed CNN’s using both the original as well as augmented dataset and the results are reported.

Feature Extraction and Classification of Chest X-Ray Images Using CNN to Detect Pneumonia

Photodegradation of commercial dye, Procion Blue HERD from real textile wastewater using nanocatalysts

Wastewater containing dyes emanating from textile mills is strongly colored and is carcinogenic in nature. In order to reduce pollution load it is desirable to degrade the dye into non-toxic form before its discharge into the main stream. The present paper reports the photocatalytic degradation of malachite green (MG). MG is used to dye materials like silk, paper and leather. The batch experiments were carried out by irradiating the aqueous solution of dye in the presence of photocatalysts and UV light. The photocatalysts used for the study are titanium dioxide (TiO2), zinc oxide (ZnO), and different ratios of ZnO and TiO2. The rate of decolorization was estimated from residual concentration spectrophotometrically. The effect of process parameters viz. pH 2–9, initial concentration of dye 5–50 ppm and amount of catalyst 0.5–1.5 g/l on degradation of the dye has also been assessed. The experimental results indicated that, ZnO efficiently compete with TiO2 in terms of percentage degradation of MG. Maximum d...

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Priti Bansal

Papers

Photocatalytic degradation of azo dye in aqueous TiO2 suspension: Reaction pathway and identification of intermediates products by LC/MS

Feature Extraction and Classification of Chest X-Ray Images Using CNN to Detect Pneumonia

Photodegradation of commercial dye, Procion Blue HERD from real textile wastewater using nanocatalysts

Studies on photodegradation of malachite green using TiO2/ZnO photocatalyst

Photodegradation of commercial dye, CI Reactive Blue 160 using ZnO nanopowder: Degradation pathway and identification of intermediates by GC/MS