Subject(s)
Antiviral Agents/administration & dosage , Carcinoma, Hepatocellular/epidemiology , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/epidemiology , Liver Neoplasms/epidemiology , Antiviral Agents/adverse effects , Carcinoma, Hepatocellular/chemically induced , Carcinoma, Hepatocellular/diagnosis , Hepatitis C, Chronic/diagnosis , Humans , Liver Neoplasms/chemically induced , Liver Neoplasms/diagnosisABSTRACT
Photocatalysis has emerged as an advance and environmental-friendly process for breakdown of organic contaminants in wastewater. This work reports facile synthesis and characterization of stable magnetic core-shell-shell Fe3O4/SiO2/TiO2 nanoparticles and their effectiveness for photocatalysis. The surface morphology, crystal structure, and chemical properties of the photocatalyst were characterized by using scanning electron microscope (SEM), energy-dispersive X-ray (EDX), X-ray diffraction (XRD), and nitrogen physisorption. Stability of synthesized nanoparticles in aqueous medium was tested by leaching test. The photocatalytic degradation of 2-chlorophenol was investigated and reaction parameters for best catalyst performance were optimized. Catalyst dose of 0.5 g/L under optimized conditions produced complete degradation of 25 mg/L 2-chlorophenol (2-CP) within 130 min of 100-W ultraviolet (UV) irradiation while 97.2 % degradation of 50 mg/L 2-CP was achieved within 3 h. The rate of photocatalytic degradation was determined by considering pseudo first-order kinetics and Hugul's kinetic equations. The Hugul's kinetics was found to provide a better interpretation of the experimental results than the generally adopted pseudo first-order reaction kinetics.
Subject(s)
Chlorophenols/chemistry , Environmental Restoration and Remediation/methods , Ferric Compounds/chemistry , Magnetite Nanoparticles/chemistry , Photolysis , Silicon Dioxide/chemistry , Titanium/chemistry , Wastewater/chemistry , Water Pollutants, Chemical/chemistry , Catalysis , Chlorophenols/analysis , Microscopy, Electron, Scanning , Ultraviolet Rays , Water Pollutants, Chemical/analysis , X-Ray DiffractionABSTRACT
Many imaging applications deal with the detection of small targets or spots embedded within an inhomogeneous background. We present a method that accomplishes a multiresolution detection on the wavelet-transformed image. The targets are separated from the background by the exploitation of Renyi's information, which is evaluated at the different decomposition levels of the wavelet transform. The scale-dependent candidate detections are successively combined by means of majority voting for final detection. Connections with results provided in different fields such as multifractal analysis, generalized information measures in scale-space, and cross-entropy analysis in fine-to-coarse transformations are discussed. Detection performance is investigated through an example from medical image analysis.
Subject(s)
Diagnostic Imaging , Entropy , Differential Threshold , Female , Humans , Mammography , Models, TheoreticalABSTRACT
Microcalcification detection is widely used for early diagnosis of breast cancer. Nevertheless, mammogram visual analysis is a complex task for expert radiologists. In this paper, we present a new method for computer aided detection of microcalcifications in digital mammograms. The detection is performed on the wavelet transformed image. The calcifications are separated from the background by exploiting the evaluation of Renyi's information at the different decomposition levels of the wavelet transform. Experiments are performed on a standard and publicly available dataset and the results are evaluated with respect to recent achievements reported in the literature.
