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Semi-coking wastewater contains a rich source of toxic and refractory compounds. Three-dimensional electro-Fenton (3D/EF) process used CuFe2O4 as heterocatalyst and activated carbon (AC) as particle electrode was constructed for degrading semi-coking wastewater greenly and efficiently. CuFe2O4 nanoparticles were prepared by coprecipitation method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy disperse spectroscopy (EDS). Factors like dosage of CuFe2O4, applied voltage, dosage of AC and pH, which effect COD removal rate of semi-coking waste water were studied. The results showed that COD removal rate reached to 80.9% by 3D/EF process at the optimum condition: 4 V, 0.3 g of CuFe2O4, 1 g of AC and pH = 3. Trapping experiment suggesting that hydroxyl radical (•OH) is the main active radical. The surface composition and chemical states of the fresh and used CuFe2O4 were analyzed by XPS indicating that Fe, Cu, and O species are involved into the 3D/EF process. Additionally, anode oxidation and the adsorption and catalysis of AC are also contributed to the bleaching of semi-coking waste water. The possible mechanisms of 3D/EF for degrading semi-coking waste water by CuFe2O4 heterocatalyst were proposed. [ABSTRACT FROM AUTHOR]

The theory of selective photothermolysis (SP) is used in many fields of laser surgery and medicine. As several parameters and a number of complicated photothermal interactions are involved in SP, numerical simulations have been providing an important and effective way in SP studies. However, with different photothermal models of SP, simulated results differ considerably. In addition, insufficient attention has been paid to tissue pressure variation during SP in these models, so that vessel rupture and other clinical phenomena cannot be explained. A novel photothermal model of SP was proposed using a Monte Carlo method to simulate the laser transport in the tissue, a heat transfer equation with dynamically changing vaporization temperature to calculate the temperature distribution, and the Arrhenius equation to predict the thermal damage. A factor of trapped vaporized tissue water k was introduced to describe the effects on tissue pressure, temperature, and other related parameters. It was shown that the simulation results are affected significantly by k. Temperature and thermal damage volume are almost identical, respectively, to those obtained with models with vaporization at 100°C and models without vaporization when k = 0 and 1, while thermal damage volume is close to that obtained with models of vaporization at 110°C and 130°C, respectively, when k = 0.022 and k = 0.18. To some extent, the current models without vaporization and models with vaporization at constant temperature can be regarded as special cases at specific situations of this new photothermal model of SP. In addition, more descriptive simulation results, such as temperature, thermal damage, and pressure, are accessible with this model, although the accuracy depends on the value of k, the estimation of which is planned as future work. [ABSTRACT FROM AUTHOR]

Using Bogoliubov-de Gennes formalism, the chiral order parameters in mesoscopic p-wave superconducting noncircular systems are investigated in the absence of applied magnetic field. For the perfect square or rectangular sample, a single-domain-wall state tends to emerge, accompanied by a vertical or horizontal domain wall separating the regions with different chiralities. This type of domain walls can be effectively tuned by temperature and the aspect ratio of samples, and the multi-domain-wall state containing two domain walls can be obtained. Moreover, for a p-wave square loop with a centered hole, the diagonal-symmetric mode for orders is presented, leading to four domain walls placed at the center of four arms of the loop. In particular, several peculiar domain-wall states may show up in the asymmetric square loop system with an off-centered hole. [ABSTRACT FROM AUTHOR]