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Cu2ZnSnS4 (CZTS) thin films were prepared by solid-state sulfurizing Cu-Zn-Sn(CZT) metallic precursors. The effect of sulfurization time on phases, chemical composition, surface morphology and optical properties was investigated by X-ray diffraction (XRD), Raman spectrum, energy dispersive of X-ray (EDS), scanning electron microscope (SEM) and UV-Vis, respectively. The results show that with the sulfurization time and content of Cu increase, Zn particularly decreases. The films that sulfurized over 40min occur with impurities like SnS, Sn2S3 and Cu2SnS3, which lead smaller optical band gap. When the sulfurization time is 20min, the sample is single phase CZTS thin film, which surface is uniform and even, Cu-poor and Sn-rich. The absorption coefficient is over 104cm-1. The band gap energy is estimated 1.56eV.

(Fe0.52Co0.30Ni0.18)73Cr17Zr10 amorphous ribbons were prepared by melt-spun method and annealed at different temperatures. X-ray diffraction, atomic force microscopy and vibrating sample magnetometer were adopted to study the effect of annealing temperature on the microstructure and magnetic properties of this alloy.The results show that the crystallization process of this alloy is amorphous→α-Fe(Co)+amorphous'→α-Fe(Co)+Cr2Ni3+Fe3Ni2+Cr2Zr+ unidentified phase. When annealing temperature Ti is lower than Tg, the Ms increases slightly as a result of relaxation of the internal stress of the as-quenched amorphous alloy. When Ti is in between Tx and Tp1, the Ms significantly increases due to the partial crystallization of amorphous precursors to create a homogeneous distribution of α-Fe(Co) nanocrystals within a residual amorphous matrix. When Ti is higher than Tp1, the Ms drops rapidly, which may be caused by the grain growth and the formation of paramagnetic phase. This alloy after annealed at 565℃ has the best magnetic property(Ms=106.8A·m2·kg-1). The results of AFM observation show that in the annealed amorphous ribbons the grain size measured from AFM graphs is much larger than that of the α-Fe(Co) nanocrystal size caculated by Scherrer method, which is a typical phenomenon of coated grain.

In order to adapt to the fast development of our social requirements, it is crucial for teaching universities to maintain and their high-level educational function and to improve and enhance their capability on innovation independently. A break-through exploration on the transition from practical teaching function to dual-function on teaching and research mode in the normal universities has been started since 2005. Therefore, our discussion mainly focuses on the necessity of constructing or increasing the large-scale instruments on the experimental platform, and emphasizes on the multifunction on the transition exploration as well. [ABSTRACT FROM AUTHOR]

To timely and accurately acquire the spatial distribution pattern of wetlands is of significance for the dynamic monitoring, conservation, and sustainable utilization of wetlands. The small remote sensing satellite constellations A/ B stars (HJ-1A/1B stars) for environmental hazards were launched by China for monitoring terrestrial resources, which could provide a new data source of remote sensing image acquisition for retrieving wetland types. Taking Liaohe Delta as a case, this paper compared the accuracy of wetland classification map and the area of each wetland type retrieved from CCD data (HJ CCD data) and TM5 data, and validated and explored the applicability and the applied potential of HJ CCD data in wetland resources dynamic monitoring. The results showed that HJ CCD data could completely replace Landsat TM5 data in feature extraction and remote sensing classification. In real-time monitoring, due to its 2 days of data acquisition cycle, HJ CCD data had the priority to Landsat TM5 data (16 days of data acquisition cycle). [ABSTRACT FROM AUTHOR]

To timely and accurately acquire the spatial distribution pattern of wetlands is of significance for the dynamic monitoring, conservation, and sustainable utilization of wetlands. The small remote sensing satellite constellations A/B stars (HJ-1A/1B stars) for environmental hazards were launched by China for monitoring terrestrial resources, which could provide a new data source of remote sensing image acquisition for retrieving wetland types. Taking Liaohe Delta as a case, this paper compared the accuracy of wetland classification map and the area of each wetland type retrieved from CCD data (HJ CCD data) and TM5 data, and validated and explored the applicability and the applied potential of HJ CCD data in wetland resources dynamic monitoring. The results showed that HJ CCD data could completely replace Landsat TM5 data in feature extraction and remote sensing classification. In real-time monitoring, due to its 2 days of data acquisition cycle, HJ CCD data had the priority to Landsat TM5 data (16 days of data acquisition cycle).

Notch signaling controls multiple developmental processes, thus demanding versatile functions. We have previously shown that this may be partly achieved by accelerating ubiquitin-mediated degradation of important regulators of differentiation. However, the underlying mechanism was unknown. We now find that Notch signaling transcriptionally activates the gene encoding ankyrin-repeat SOCS box-containing protein 2 (Asb2). Asb2 promotes the ubiquitination of Notch targets such as E2A and Janus kinase (Jak) 2, and a dominant-negative (DN) mutant of Asb2 blocks Notch-induced degradation of these proteins. Asb2 likely binds Jak2 directly but associates with E2A through Skp2. We next provide evidence to suggest that Asb2 bridges the formation of non-canonical cullin-based complexes through interaction with not only ElonginB/C and Cullin (Cul) 5, but also the F-box-containing protein, Skp2, which is known to associate with Skp1 and Cul1. Consistently, ablating the function of Cul1 or Cul5 using DN mutants or siRNAs protected both E2A and Jak2 from Asb2-mediated or Notch-induced degradation. By shifting monomeric E3 ligase complexes to dimeric forms through activation of Asb2 transcription, Notch could effectively control the turnover of a variety of substrates and it exerts diverse effects on cell proliferation and differentiation.