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The growth of Cu2O crystal planes was be controlled by adding surfactant to the NaCl solution in this manuscript. The structure and composition of the synthesized Cu2O particles were characterized by X‑ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), and specific surface area test method (BET). The photocatalytic activities were evaluated by degrading methyl orange (MO) solution under magnetic stirring. The results shown that the synthesized Cu2O particle was spherical self-assembly structure when the surfactant was CTAB, and behaved higher degradation performance. Under dark conditions, the adsorption efficiency of 100 mg L–1 MO solution reached 67.08% in the first 1 min by 0.33 g L–1 CTAB-Cu2O, and after 15 min, the adsorption degradation efficiency of MO had reached 99.17%. The maximum adsorption capacity of CTAB-Cu2O was 297.28 mg g–1. The adsorption kinetics obeyed pseudo-second-order kinetics and followed the Freundlich isotherm. [ABSTRACT FROM AUTHOR]

In this paper, the problem of open-switch faults of a voltage source inverter system is investigated. A new fault diagnosis method based on an observer and an adaptive threshold is proposed. This method only needs to utilize the signals existing in a system without the need for extra hardware circuits. First, an observer is designed on a model of a three-phase voltage source inverter system to estimate currents. Then, an adaptive threshold is designed on fault residuals, dynamics of the currents and variations of the system operating state. Moreover, the dead time and switching delay time are also included in the threshold to consider practical applications. Furthermore, to achieve on-line real-time diagnosis and to improve the reliability of the proposed method, the averages of the current residuals in a current fundamental period are defined as diagnostic variables. Finally, the reliability and effectiveness of the proposed method are verified by simulation and experiment results. [ABSTRACT FROM AUTHOR]

To investigate DNA-dependent protein kinase (DNA-PK) expression, and its relationship with lymphatic metastasis in colorectal cancer. Tumor tissues from 60 patients, divided into two groups according to lymphatic metastasis, were immunohistochemically stained to detect the DNA-PK expression including Ku70, Ku80 and PKcs proteins. Positivity of both Ku70 and Ku80 in colorectal cancer was negatively correlated with lymphatic metastasis with an r value of −0.57 and −0.38, respectively. Similar correlation was found between Ku expression, especially Ku70, and long-term survival. PKcs, however, displayed no significant correlation. Statistical analysis failed to detect any correlation between DNAPK expression, and clinical characteristics, such as age, sex, tumor location, tumor thickness and distant metastasis ( P > 0.05). DNA-PK expression, especially Ku70 expression, is negatively correlated with lymphatic metastasis, and the survival of patients with colorectal cancer. Ku70 expression may be a potential indicator for the preoperative evaluation, and prognosis in colorectal cancer. [ABSTRACT FROM AUTHOR]