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71.
Sbastien Gibanel Valrie Heroguez Jacqueline Forcada 《Journal of polymer science. Part A, Polymer chemistry》2002,40(16):2819-2827
New diblock macromonomers were used as reactive emulsifiers in the emulsion polymerization of styrene. The nature of the reactive group, the molecular weight, the length of the poly(ethylene oxide) (PEO) block, and the molecular structure of the macromonomer were systematically investigated during this process by analyzing the evolution of the conversion and particle diameters. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2819–2827, 2002 相似文献
72.
Jacqueline Jiménez Mildred López Vladimir Carranza Angel Mendoza Jenaro Varela Estibaliz Sansinenea Aurelio Ortiz 《Tetrahedron letters》2017,58(3):235-239
An alternative methodology for the synthesis of chiral 3-(p-tolyl) butanoic acids is presented. This was accomplished through the diastereoselective hydrogenation reaction of different chiral N-3-(p-tolyl) but-2-enamides, using Pd/C in EtOH, to produce the corresponding chiral N-3-(p-tolyl) butanamides with high chemical yields and moderate diastereomeric ratios. Removal of the chiral auxiliary from N-3-(p-tolyl) butanamides gave the respective enantiomerically pure acids. 相似文献
73.
Thomas L. Theis Bhavik R. Bakshi Delcie Durham Vasilis M. Fthenakis Timothy G. Gutowski Jacqueline A. Isaacs Thomas Seager Mark R. Wiesner 《固体物理学:研究快报》2011,5(9):312-317
While significant advances in our understanding of the behavior of engineered nanoparticles in the environment continue, there remains a need to engage the nanoparticle research community directly in the development and evaluation of environmentally benign nanoparticles to ensure that nanomaterial‐based industries emerge as tools for sustainability rather than environmental liabilities. Current research efforts aimed at understanding the environmental implications of nanotechnology emphasize existing groups of nanoparticles and products already in commercial distribution. While this is clearly necessary, this approach fails to identify and address the many tradeoffs associated with product performance and environmental quality. We believe this to be a critical gap in the ongoing exploration of nanostructured materials and their properties and applications. We posit that a number of issues are not being holistically addressed, including resource availability and allocation, manufacturing energy requirements and embodied energy, material efficiency, environmental properties of nanomaterials and nanoproducts, and waste generation. An interdisciplinary approach to research, based on the life cycle paradigm and devoted to the identification, investigation, synthesis, testing, and analysis of groups of new, more environmentally conscious nanoparticles is needed. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Bowes KF Cole JM Husheer SL Raithby PR Savarese TL Sparkes HA Teat SJ Warren JE 《Chemical communications (Cambridge, England)》2006,(23):2448-2450
The structure of a new metastable geometric isomer of [Ru(NH3)4(H2O)(SO2)][MeC6H4SO3]2 in which the SO2 group is coordinated through a single oxygen in an eta1-OSO bonding mode has been determined at 13 K; the new isomer was obtained as a 36% component of the structure within a single crystal upon irradiation using a tungsten lamp. 相似文献
79.
A new catalyst system for the Pd-catalyzed cross-coupling of organozinc reagents with aryl halides (Negishi coupling) has been developed. This system permits efficient preparation of hindered biaryls (tri- and tetra-ortho-substituted), functions effectively at low levels of catalyst, and tolerates a wide range of functional groups and heterocyclic substrates. A systematic study of ligand structure was performed and was correlated with catalyst activity. 相似文献