992 resultados para 11-103


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The desulfurization of thiophene on Raney Ni and rapidly quenched skeletal Ni (RQ Ni) has been studied in ultrahigh vacuum (UHV) by X-ray photoelectron spectroscopy (XPS). The Raney Ni or RQ Ni can be approximated as a hydrogen-preadsorbed polycrystalline Ni-alumina composite. It is found that thiophene molecularly adsorbs on Raney Ni or RQ Ni at 103 K. At 173 K, thiophene on alumina is desorbed, while thiophene in direct contact with the metallic Ni in Raney Ni undergoes C-S bond scission, leading to carbonaceous species most probably in the metallocycle-like configuration and atomic sulfur. On RQ Ni, the temperature for thiophene dissociation is about 100 K higher than that on Raney Ni. The lower reactivity of RQ Ni toward thiophene is tentatively attributed to lattice expansion of Ni crystallites in RQ Ni due to rapid quenching. The existence of alumina and hydrogen may block the further cracking of the metallocycle-like species on Raney Ni and RQ Ni at higher temperatures, which has been the dominant reaction pathway on Ni single crystals. By 473 K, the C Is peak has disappeared, leaving nickel sulfide on the surface.

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Mature human interleukin-11 (HuIL-11) is a cytokine consisting of 178 amino acid residues that results from scission of the N-terminal signal peptide, consisting of 21 amino acid residaues, from the corresponding nascent polypeptide. A DNA fragment encoding a truncated HuIL-11 (trHuIL-11), with an additional 5 amino acid residues removed from the N-terminus, was cloned into vector pGEX-2T between the BamHI site and the EcoRI site. Upon transformation with Escherichia coli BL21, the construct over-produced a glutathione S-transferase (GST)-fused protein in a soluble form after IPTG induction. The fusion protein was initially fractionated with butyl-Sepharose 4 fast flow column and by affinity chromatography using a GSH-Sepharose 4B column. On-site enzymatic release with thrombin gave the target protein at 96% purity as judged by SDS-PAGE and HPLC. Expression of the interleukin as a GST-fused protein thus greatly improved downstream processing. Subsequent biological activity assay suggested that trHuIL-11 had similar activity profile to the naturally produced sample and may be a promising candidate for further development as biopharmaceutical.

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O balanço comercial do setorvitivinícola nacional sinaliza para o equilíbrio no curto prazo. Em 2005, houve acréscimo no valor das exportações brasileiras de uvas, de 85,39% em relação ao ano anterior, perfazendo um total de 120,87 milhões de dólares. O déficit de 5,45 milhões de dólares representa apenas 4,51% do valor das e~ortações e foi reduzido em 86,72%;em relação ao ano de 2004. Cabe destacar o excelente desempenho nas vendasde uvas de mesa, 103,35% superior, en?:valor, ao ano de 2004, aliado aos acréscimos das exportações de vinhos de mesa (61,38%).

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McInnes, C., 'A different kind of war? 11 September and the United States' Afghan war'. Review of International Studies, 29 (2), 165-184. RAE2008

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To accompany exhibition curated by Robert Meyrick, 'Gwilym Prichard', National Library of Wales; Oriel Theatr Clwyd; Oriel Plas Glyn-y-Weddw; Graham Sutherland Gallery, Picton Castle. pp.103

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Handwritten letter from Daniel D. Whedon to nephew, Daniel Avery Whedon. Dated November 30, 1881.

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Handwritten letter from Timothy Merritt to sister (?) Ruth Merritt regarding her loss of religious conviction. Dated Nov. 10, 1818.

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Handwritten letter from Timothy Merritt to Rev. Epaphras Kibby regarding lodging and preaching schedule. Sent in care of Mr. Lambert. Dated Jan. 11, 1801, Bath, ME.

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Three page handwritten letter to nephew, Daniel Avery Whedon, from Daniel D. Whedon. Dated 11/14/1881.