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Mixed-anionic compounds have caught considerable attention due to their flexible coordination manners and abundant physical properties. Four new chalcohalides RbIn4S6Cl (1), CsIn4S6Cl (2), Pb5Sn3S10Cl2 (3) and Pb5Sn3Se10Cl2 (4) were successfully obtained by the high-temperature halide salt flux method. Compounds 1 and 2 have layered structures that consist of octahedral InS6 and aliovalent-anionic InS3Cl units. Compounds 3 and 4 feature 3-D structural frameworks built by [Pb4SnQ8Cl4]6− and [PbSn2Q6]2− (Q = S and Se) polyhedral chains, in which partial Pb2+ cations are coordinated by Q2− and Cl− anions. Compounds 1–4 have optical band gaps close to the wavelength range of visible light and exhibit significant photocurrent responses of 28.75 nA cm−2, 55.12 nA cm−2, 19.58 mA cm−2, and 36.12 μA cm−2 with on/off ratios 30.0, 2.5, 15.7 and 2.6, respectively, implying their potential for photovoltaic applications. To the best of our knowledge, compound 3 has the largest photocurrent response among all non-oxides. In addition, the activation energies of 1–4 are well below 0.3 eV, which makes these compounds interesting for potential applications in electrochemical devices. This work sheds light on the exploration of promising photocurrent response materials in the mixed-anionic compound system. [ABSTRACT FROM AUTHOR]

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]

Four Cd II coordination polymers, namely {[Cd(L 334 )(Cl) 2 ](CH 3 OH)} n ( 1 ), [Cd(L 334 )(Cl)(dca)] n ( 2 ), {[Cd(L 334 )(Cl) 1.33 (N 3 ) 0.67 ](H 2 O)} n ( 3 ), and {[Cd(L 334 )(SCN) 2 (H 2 O)](H 2 O) 1.5 (CH 3 OH)} n ( 4 ), have been synthesized by the conventional reactions of CdCl 2 and 3,4-bis(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole (L 334 ) or in the presence of different pseudohalides dicyanamide (dca), azide (N 3 ), and thiocyanate (SCN), respectively as auxiliary ligands. Complexes 1 – 3 exhibit the isostructural 2D layered network structures, whereas complex 4 shows a distinct 2D network with dimeric Cd II subunits. The structural discrepancy in 1 – 4 indicates the significant influence of pseudohalide anions on the structural assembly of Cd II coordination polymers with 3,4-bis(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole. In addition, thermogravimetric and fluorescent properties for all complexes and the ligand have also been investigated. [ABSTRACT FROM AUTHOR]

Three coordination polymers, namely {[Cu(5-nipa) (L22)](H2O)2}n (1), [Zn(5-nipa)(L22)(H2O)]n (2), and {[Cd2(5-nipa) 2(L22)(H2O)3](H2O)3.6}n (3), were prepared under similar synthetic method based on 1,2-(2-pyridyl)-1,2,4-triazole (L22) and ancillary ligand 5-nitro-isophthalic acid (5-H2nipa) with CuII, ZnII, and CdII perchlorate, respectively. All the complexes were characterized by IR spectroscopy, elemental analysis, and powder X-ray diffraction (PXRD) patterns. Single-crystal X-ray diffraction indicates that complexes 1 and 2 show similar 1D chain structures, whereas complex 3 exhibits the 2D coordination network with hcb topology. The central metal atoms show distinct coordination arrangements ranging from distorted square-pyramid for CuII in 1, octahedron for ZnII in 2, to pentagonal- bipyramid for CdII in 3. The L22 ligand adopts the same (η3,μ2) coordination fashion in complexes 1-3, while the carboxyl groups of co-ligand 5-nipa2- adopt monodentate fashion in 1 and 2 and bidentate chelating mode in 3. These results indicate that the choice of metal ions exerts a significant influence on governing the target complexes. Furthermore, thermal stabilities of complexes 1-3 and photoluminescent properties of 2 and 3 were also studied in the solid state. [ABSTRACT FROM AUTHOR]

This paper proposes an improved transient negative-sequence calculation formula for a large-capacity nuclear power generator system under unbalanced network conditions. Because of the disadvantages of traditional transient negative-sequence ratings, I2 *2 t is concluded to be inadequate for rating the generator imbalance capability. In fact, many factors, such as the possible fault asymmetry, the duration of the fault and non-periodic components, should also be considered when rating a generator. According to the inherent relation between rotor heating and generator imbalance capability, the non-periodic component is added to the improved transient negative-sequence formula. In this paper, an AP1000 nuclear turbo-generator was examined as a model to systematically analyse the electromagnetic properties and generator transient negative-sequence capability affected by different types of typical short circuits. A comprehensive comparison based on accident examples, experimental results and extensive simulations shows that the improved transient negative-sequence formula not only significantly enhances the assessment accuracy of large-capacity generator imbalance capability but also provides a theoretical reference for the related research of large-capacity generator systems. Copyright © 2015 John Wiley & Sons, Ltd. [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]