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Diorganotin dihalide complexes with bidentate nitrogen ligands exhibit some pharmaceutical activities such as antitumour activity, antiviral activity and anti-microbiological activity[1-3], we have synthesized some diorganotin dihalide complexes with bidentate nitrogen ligands, one of which is dibutyldichloro(1,10-phenanthroline-N 1,N 10)tin. A solution of dibutyltin dichloride (1.22 g, 4 mmol) in benzene (20 ml) was added to a solution of 1,10-phenanthroline (0.72 g, 4 mmol) in benzene (20 ml). The mixture was refluxed for 4 h, the solid that appeared upon cooling was filtered and recrystallized from absolute ethanol to give the title compound as white crystal (1.82 g, 94%)

ABI4 Mediates Antagonistic Effects of Abscisic Acid and Gibberellins at Transcript and Protein Levels

Abscisic acid (ABA) and gibberellins (GA) are plant hormones which antagonistically mediate numerous physiological processes, and their optimal balance is essential for normal plant development. However, the molecular mechanism underlying ABA and GA antagonism still needs to be determined. Here, we report that ABA- INSENSITIVE 4 (ABI4) is a central factor for GA/ABA homeostasis and antagonism in post-germination stages. ABI4 over-expression in Arabidopsis (OE-ABI4) leads to developmental defects including a decrease in plant height and poor seed production. The transcription of a key ABA biosynthetic gene, NCED6, and of a key GA catabolic gene, GA2ox7, is significantly enhanced by ABI4 over-expression. ABI4 activates NCED6 and GA2ox7 transcription by directly binding to the promoters, and genetic analysis revealed that mutation in these two genes partially rescues the dwarf phenotype of ABI4 overexpressing plants. Consistently, ABI4 overexpressing seedlings have a lower GA/ABA ratio compared to the wild type. We further show that ABA induces GA2ox7 transcription while GA represses NCED6 expression in an ABI4-dependent manner; and that ABA stabilizes the ABI4 protein, whereas GA promotes its degradation. Taken together, these results propose that ABA and GA antagonize each other by oppositely acting on ABI4 transcript and protein levels

Iron and nickel doped CoSe2 as efficient non precious metal catalysts for oxygen reduction

Iron and nickel doped CoSe2 were prepared by solvothermal method, and they were proved to be ternary chalcogenides by series of physical characterization. The effects of the iron and nickel contents on the oxygen reduction reaction were investigated by electrochemical measurements, and the highest activities were obtained on Co0.7Fe0.3Se2 and Co0.7Ni0.3Se2, respectively. Both Co0.7Fe0.3Se2 and Co0.7Ni0.3Se2 presented four-electron pathway. Furthermore, Co0.7Fe0.3Se2 exhibited more positive cathodic peak potential (0.564 V) and onset potential (0.759 V) than these of Co0.7Ni0.3Se2 (0.558 V and 0.741 V). And Co0.7Fe0.3Se2 displayed even superior stability and better tolerance to methanol, ethanol and ethylene glycol crossover effects than the commercial Pt/C (20 wt% Pt)

β-Glucan Oligosaccharide Enhances CD8+ T Cells Immune Response Induced by a DNA Vaccine Encoding Hepatitis B Virus Core Antigen

DNA vaccination can induce specific CD8+ T cell immune response, but the response level is low in large mammals and human beings. Coadministration of an adjuvant can optimize protective immunity elicited by a DNA vaccine. In this study, we investigated the effect of a synthetic glucohexaose (β-glu6), an analogue of Lentinan basic unit, on specific CD8+ T cell response induced by a DNA vaccine encoding HBcAg (pB144) in mice. We found that β-glu6 promoted the recruitment and maturation of dendritic cells, enhanced the activation of CD8+ and CD4+ T cells and increased the number of specific CD8+/IFN-γ+ T cells in lymphoid and nonlymphoid tissues in mice immunized by pB144. Immunization with pB144 and β-glu6 increased the anti-HBc IgG and IgG2a antibody titer. These results demonstrate that β-glu6 can enhance the virus-specific CTL and Th1 responses induced by DNA vaccine, suggesting β-glu6 as a candidate adjuvant in DNA vaccination

Phase Transition and Optical Properties for Ultrathin KNbO 3

Fascicular KNbO3 nanowires with tetragonal perovskite structures and ultrasmall diameters are synthesized by hydrothermal route at about 150°C for 24 hours. The concentrations of medium alkalinity have influenced phase structures and the final morphologies of the products significantly by modifying the conditions in process. The as-prepared KNbO3 nanowires exhibit three phase transitions at about 343, 454.7, and 623 K as the temperature increases from 250 to 700 K. The band gap is about 3.78 eV for KNbO3 nanowires. Photoluminescence study at room temperature reveals two visible light emission bands peaking at ~551 and 597 nm, respectively, which may be due to the oxygen vacancies, site niobium (occupy the location of Nb), and antisite niobium (occupy the location of K) in KNbO3 nanowires

Strength degradation mechanism of iron coke prepared by mixed coal and Fe2O3

Iron coke, as a new type of blast furnace burden is helpful for energy saving, emission reduction and green production of iron making. This study aims to investigate the strength degradation mechanism of iron coke prepared by mixed coal and Fe2O3 to provide a theoretical direction to improve its strength. Coking and pyrolysis experiments of mixed coal and Fe2O3 were carried out between 400 and 500 ℃ temperature. Gieseler plastometer and derivative thermogravimetric (DTG) showed that added Fe2O3 inhibited the thermoplasticity and pyrolysis process of mixed coal during coking. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) results showed that added Fe2O3 decreased the aromaticity and average stacking height, but increased the interlayer spacing of crystallite, aliphatic chain length and hydrocarbon-generating potential of mixed coal during coking. Further, gas chromatography-mass spectrometer (GCsingle bondMS) analysis suggested that the added Fe2O3 inhibited the cleavage of Calsingle bondO, Calsingle bondS, Calsingle bondN, Calsingle bondCar and Calsingle bondCal bonds, reduced the generation of ethylbenzene, o-xylene and unbranched alkanes with carbon atoms in 24–26, thus decreased the amount of fluid phase generated in coking and ultimately degraded the strength of iron coke