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Two isostructural Cd(II) coordination polymers (CPs), namely {[Cd(L)(H2O)2](ClO4)2}n (I) and {[Cd(L)(H2O)(dca)](ClO4)}n (II), have been synthesized by assembling a multidentate building block 3,4-bis(3-pyridyl)−5-(4-pyridyl)−1,2,4-triazole (L) with Cd(ClO4)2 in the absence or presence of sodium dicyanamide (Na(dca)). Single-crystal X-ray diffraction reveals that both CPs show the similar 2D-layered structures. Interestingly, they present distinct adsorption capacities (7% for I and 18% for II) toward the anionic dye methyl orange (MO). The results indicate that complex II shows higher adsorption ability, which may be ascribed to the charge effect of cationic framework. [ABSTRACT FROM AUTHOR]

Abstract—This article analyzes the fault location, negative-sequence component, and current harmonic content of the first AP1000 third-generation 1250-MVA nuclear half-speed (four-pole) turbo-generator with internal phase faults. To this end, the internal armature winding fault of an AP1000 turbo-generator is systemically explored by using both an experimental method and the field-circuit coupling simulation method. The internal phase short circuit is one of the worst faults that a generator can experience; such a fault may have serious consequences for nuclear power large-capacity turbo-generators because of the severe mechanical and heat damage caused by the high current. To understand these problems, the possible position of the internal short circuit is investigated in detail according to the winding arrangement of the AP1000 turbo-generator, and the internal short-circuit faults of two branches from different phases are calculated. Furthermore, the negative-sequence current can be captured by analyzing each harmonic of the short-circuit current. In addition to the calculations, the steady-state negative-sequence component and degree of asymmetry of the internal phase short-circuit current in different fault locations are also obtained. The results significantly enhance the accuracy assessment of a large-capacity generator imbalance and provide a theoretical reference for the protection of a large-capacity generator system. [ABSTRACT FROM PUBLISHER]