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Noticeable Loss (noticeable + loss)
Selected AbstractsPacking capillary electrochromatography columns using vacuum , A preliminary studyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 14 2004Qishu Qu Abstract This paper introduces a novel method for packing Capillary Electrochromatography Columns (CEC). Using vacuum packing methodology, silica particles as small as 1 ,m were successfully packed into the capillary columns with 75 ,m inner diameter. The columns are very stable and show no noticeable loss in efficiency after 200 sample injections. The performance of these vacuum packed capillary columns was evaluated with a mixture of aromatic and non-aromatic compounds. A 24 cm long capillary column can produce peak efficiencies of around 45 000 plates for benzene. [source] Catalytic behavior of wool,Rh complex in asymmetric hydrogenation of 2-methyl furan,POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 3-5 2003Man He Abstract A Wool,Rh complex was prepared by the reaction of wool with RhCl3·3H2O in ethanol solution, and was found to be useful as a chiral catalyst for the asymmetric hydrogenation of 2-methyl furan to (S)-(+)-2-methyl tetrahydrofuran at 28,°C and under atmospheric hydrogen pressure. When an appropriate Rh content in the Wool,Rh complex was selected, the yield and optical yield amounted to 53.7 and 76.9%, respectively, and the Wool,Rh complex catalyst could be reused several times without any noticeable loss in its optical catalytic activity. Wool is a very cheap natural biopolymer ligand, and Wool,Rh complex is very easy to prepare, and it is a very active, enantioselective and stable chiral catalyst for asymmetric hydrogenation of 2-methyl furan. Copyright © 2003 John Wiley & Sons, Ltd. [source] Ni(OAc)2: a highly efficient catalyst for the synthesis of enaminone and enamino ester derivatives under solvent-free conditionsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 10 2010Ju-Yan Liu Abstract Ni(OAc)2 was found to be an efficient catalyst for the synthesis of ,-enamino ketones or esters from ,-dicarbonyl compounds and amines under solvent-free conditions. The reusability of the catalyst was successfully examined without noticeable loss of its catalytic activity. Copyright © 2010 John Wiley & Sons, Ltd. [source] Cultured Autologous Human Cells for Hard Tissue Regeneration: Preparation and Characterization of Mesenchymal Stem Cells from Bone MarrowARTIFICIAL ORGANS, Issue 1 2004Noriko Kotobuki Abstract:, Mesenchymal stem cells (MSCs) are multipotent cells and can be induced in vitro and in vivo to differentiate not only into the variety of mesodermal cells, but into either ectodermal or endodermal cells. This capability indicates the usefulness of MSCs for tissue engineering. Cell surface antigen analyses using various types of CD antibodies demonstrated that adherent fibroblastic cells derived from fresh human bone marrow are mesenchymal types and the cells showed extensive capability for proliferation and/or differentiation. We labeled the adherent cultured marrow cells as MSCs and, significantly, found the MSCs could even proliferate from aged marrow cells. After about sixteen days of culturing, we were able to harvest 100 million MSCs from only 3 ml of fresh human marrow. Moreover, the MSCs could be cryopreserved at ,80°C without noticeable loss of viability and capability of osteoblastic differentiation. These results indicate that MSCs hold promise for utilization in hard tissue regeneration. [source] | ||||||||||