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Negative temperature coefficient (NTC) thermistors feature higher sensitivities and faster response speeds and thereby have particular applications in many fields. However, current NTC thermistors are mostly based on inorganic ceramic materials, which show obvious drawbacks in material synthesis, property modulation, and flexible film fabrication. Herein, we report, for the first time, the promising application of an inorganic–organic hybrid NTC thermistor. A new lead-free hybrid iodo bismuthate [1,1′,1″-(benzene-1,3,5-triyl)tris(3-methyl-1H-imidazol-3-ium)]Bi2I9[denoted as (Me3TMP)Bi2I9] was synthesized by a “double-free” strategy. (Me3TMP)Bi2I9features a lead-free binuclear bismuth iodine anion charge compensated by a “classic hydrogen-bond-free” cation. (Me3TMP)Bi2I9exhibits remarkable stability in water and UV light irradiation and shows the largest temperature sensitivity coefficient among all reported NTC materials. Theoretical calculation and detailed structural analysis disclose that the seriously distorted (BiI6) octahedra are responsible for the intriguing NTC effect for (Me3TMP)Bi2I9.

We employ the static and dynamic copula models to investigate whether technical indicators provide information on volatility in the next trading day, where the volatility is measured by daily realized volatility. Our empirical results, based on long samples of 8 well-known stock indexes, suggest that a significant and asymmetric tail dependence between the technical indicators based on moving average and the next day volatility. The level of dependence change over time in a persistent manner. And the dependence structure presents some distinct differences between emerging market indexes and developed market indexes. These results indicate that the technical indicators can provide information on the next day volatility at extremes, and are less informative at normal market.

According to the framework of Technological regimes theory, the Technological regimes can be decomposed into four-dimensional elements: technological opportunities, appropriation, cumulative nature of technological progress and knowledge-based features. We selected 25 groups of data from manufacturing industries in a certain province in 2006 and study the impact of four dimensional elements of technological regimes on the establishment of industry technological standards by the method of Logistic regression. The results show that each dimension of technological regimes affects establishment of the industry technological standards to a certain extent in different directions. The size of a firm and its market needs of new products should also be considered at the same time.

Zinc oxide (ZnO) and Zirconium (Zr) doped ZnO nano films have been successfully fabricated by radio frequency (RF) magnetic sputtering. The crystal structure and morphology were investigated by X-ray Diffraction (XRD), Field Emission-Scanning Electron Microscope (FE-SEM) and Transmission Electron Microscope (TEM). As the doped Zr content increases, ZnO nano films show various morphologies. The optical band gap of pure ZnO films increases from 3.27 eV to 3.53 eV with Zr concentration increasing to 9.66 at.%. After annealing, the polycrystalline structure of ZnO changes a little and the energy gap decreases. In addition, the clean and lower doped ZnO films show much lower transmittance.

Zinc oxide (ZnO) and Dysprosium (Dy) doped ZnO nano films have been successfully prepared by radio frequency (RF) magnetron sputter. Then the crystal structure, morphology and optical of the films were investigated. All the samples have a preferred orientation with the (0 0 2) orientation perpendicular to the substrates. The surface morphology of the films changes greatly with the increasing of doping content. Agglomeration appears when the doping content is excess, which may result from the recrystallization of the small crystalline grain. The average transmittance in the visible range all exceeds 80% for the different doping content films and the band gap increases from 3.26eV to 3.34eV.

Both ZnO nanocomb and nanotetrapod structures have been synthesized via a simple chemical vapor deposition process in a horizontal tube furnace. The morphology of the products is affected by the distance between the source material and the deposition substrate. The formation of nanocombs has been attributed to the self-catalysis effect of polar surface. The octahedral multiple-twin model is responsible for the formation of tetrapods and tripod-like arms at the end of nanowires. The evolutive process of them has been given out in detail and the results provided valuable models in understanding crystal growth mechanisms in nanometer building-blocks and to further grow net nanostructures. And their photoluminescence properties also have been discussed.

Aims and Background It was documented that nasopharyngeal carcinoma (NPC) is associated with Epstein-Barr virus (EBV) and that EBV-encoded latent membrane protein-1 expression (LMP1) plays an important role in the pathogenesis of NPC. In preclinical studies, arsenic trioxide (As2O3) has been identified as a promising anticancer agent for treatment of NPC. The purpose of this study is to investigate if this agent can inhibit the expression of LMP1 and therefore lead to growth inhibition of NPC cells in vitro.Methods LMP1-positive NPC cells, HNE1-LMP1, were treated with 3 umol/L of As2O3for 96 hours. The LMP1 protein expression and mRNA level in HNE1-LMP1 cells were determined by western blot, confocal immunofluorescence staining and semiquantitative reverse transcriptase reaction (RT-PCR). Apoptosis was determined by light microscopy and the TUNEL method. Alterations in the cell cycle distribution were also investigated by flow cytometry. MTT assay and colony formation assay were used to detect the proliferation of the cells. The LMP1-negative parental cell lines HNE1 and HNE2 were used as control in an attempt to elucidate the role of LMP1 in the anticancer effect of As2O3on NPC cells.Results The expression of LMP1 at the protein and mRNA level was reduced after exposure to 3 umol/L As2O3. This dose of As2O3significantly induced apoptosis and growth retardation of HNE1-LMP1 cells. In addition, more HNE1-LMP1 cells were induced to G0/G1 and G2/M arrest. The same dose of As2O3had a moderate effect on HNE1 and HNE2 cells.Conclusion Arsenic trioxide can inhibit LMP1 expression and dictate apoptosis and alterations of cell cycle distribution as well as growth retardation. LMP1-positive NPC cells are more sensitive to As2O3treatment than LMP1-negative NPC cells.

The paper mainly reviewed the optical energy gap and microhardness of Cu3N thin films. The optical energy gap increases from 0.23 eV to 1.9 eV. The microhardness of Cu3N thin films was determined to be about 3.7-8.8 GPa.