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Louis P. Jackson Ralph Andrade Ian Pleasent Brian P. Grady 《Journal of surfactants and detergents》2014,17(5):911-917
Aqueous solutions of sodium tetradecanoate (S14C) and sodium dodecanoate (S12C) were used to evaluate complicated precipitation phenomena and to monitor the effects of bulk pH adjustments on surface tension and critical micelle concentrations (CMC) determination from surface tension plots. Limited solubilities of pure sodium n-alkyl carboxylates in solution near the CMC have been reported previously many times. In this study, precipitation encountered with solutions prepared from vender-supplied S12C was eliminated through additional purification. As sodium alkyl carboxylates discussed in the literature are commonly used as received from the manufacture without additional purification, the wide range of reported CMC values as well as precipitation near the CMC for S12C are also likely due to impurities. However, complete solubility for S14C solution concentrations near the reported CMC values was not obtained through additional purification of purchased material. Hence, some CMC values reported in the literature for S14C should be reconsidered, as discontinuities in the slope of surface tension versus concentration plots are likely caused by the formation of a precipitate not micelle aggregation. In addition and in agreement with other studies, solution pH adjustments revealed a minimum surface tension for maximum solubility near the pK a value for S14C. 相似文献
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Dr. Louis Adriaenssens Dr. Qiang Liu Dr. Fanny Chaux‐Picquet Dr. Semra Tasan Dr. Michel Picquet Prof. Franck Denat Prof. Pierre Le Gendre Dr. Fernanda Marques Dr. Célia Fernandes Dr. Filipa Mendes Dr. Lurdes Gano Dr. Maria Paula Cabral Campello Dr. Ewen Bodio 《ChemMedChem》2014,9(7):1567-1573
A novel RuII(arene) theranostic complex is presented. It is based on a 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid macrocycle bearing a triarylphosphine and can be tracked in vivo by using the γ emission of 153Sm atoms. Notably, the heteroditopic ligand can be selectively metalated with ruthenium at the phosphorus atom despite the presence of other functionalities that are prone to metal coordination. Subsequent labeling with radionuclides such as 153Sm can then be performed easily. The resulting heterobimetallic complex exhibits favorable solubility and stability properties in biologically relevant media. It also shows in vitro cytotoxicity in line with that expected for this type of metallodrug, and is nontoxic to the organism as a whole. As a proof of concept, initial studies in healthy mice were performed to obtain information about the uptake, biodistribution, and excretion of the radiolabeled complex. 相似文献
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Ramzi A. Mothana Mansour S. Al-Said Nawal M. Al-Musayeib Ali A. El Gamal Shaza M. Al-Massarani Adnan J. Al-Rehaily Majed Abdulkader Louis Maes 《International journal of molecular sciences》2014,15(5):8360-8371
Chromatographic separation of the n-hexane extract of the aerial part of Plectranthus barbatus led to the isolation of five abietane-type diterpenes: dehydroabietane (1); 5,6-didehydro-7-hydroxy-taxodone (2); taxodione (3); 20-deoxocarnosol (4) and 6α,11,12,-trihydroxy-7β,20-epoxy-8,11,13-abietatriene (5). The structures were determined using spectroscopic methods including one- and two-dimensional NMR methods. Compounds (1)–(3) and (5) are isolated here for the first time from the genus Plectranthus. The isolated abietane-type diterpenes tested in vitro for their antiprotozoal activity against erythrocytic schizonts of Plasmodium falciparum, intracellular amastigotes of Leishmania infantum and Trypanosoma cruzi and free trypomastigotes of T. brucei. Cytotoxicity was determined against fibroblast cell line MRC-5. Compound (2) 5,6-didehydro-7-hydroxy-taxodone showed remarkable activity with acceptable selectivity against P. falciparum (IC50 9.2 μM, SI 10.4) and T. brucei (IC50 1.9 μM, SI 50.5). Compounds (3)–(5) exhibited non-specific antiprotozoal activity due to high cytotoxicity. Compound (1) dehydroabietane showed no antiprotozoal potential. 相似文献
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Louis Kruh 《Cryptologia》2013,37(2):142-159
The most popular microcomputers have serious security weaknesses. Their password protection gives no protection at all against anyone skilled in the art of systems programming. The system described relies upon file encryption. It is implemented entirely in software and affords moderate security without incurring high over-head or memory residence costs. 相似文献
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Louis Kruh 《Cryptologia》2013,37(4):379-380
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