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51.
Gabriela Aldea Gabrielle C. Chitanu Jacques Delaunay Jean‐Michel Nunzi Bogdan C. Simionescu Jack Cousseau 《Journal of polymer science. Part A, Polymer chemistry》2005,43(23):5814-5822
Starting from the synthesis of a new methanofullerene derivative bearing an alcohol group, we report on the preparation of a water‐soluble, fullerene‐pendant copolymer. This multifunctional, C60‐pendant maleic anhydride copolymer was characterized by conductometric titration, Fourier transform infrared and ultraviolet spectroscopy, thermogravimetric analysis, and cyclic voltammetry. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5814–5822, 2005 相似文献
52.
Gabrielle Villari Jr. 《Journal of Differential Equations》2007,234(1):337-338
53.
Agnès Rolland-Sabaté Sophie Guilois Florent Grimaud Christine Lancelon-Pin Xavier Roussel Sandrine Laguerre Anders Viksø-Nielsen Jean-Luc Putaux Christophe D’Hulst Gabrielle Potocki-Véronèse Alain Buléon 《Analytical and bioanalytical chemistry》2014,406(6):1607-1618
Asymmetrical flow field flow fractionation (AF4) has proven to be a very powerful and quantitative method for the determination of the macromolecular structure of high molar mass branched biopolymers, when coupled with multi-angle laser light scattering (MALLS). This work describes a detailed investigation of the macromolecular structure of native glycogens and hyperbranched α-glucans (HBPs), with average molar mass ranging from 2?×?106 to 4.3?×?107 g mol?1, which are not well fractionated by means of classical size-exclusion chromatography. HBPs were enzymatically produced from sucrose by the tandem action of an amylosucrase and a branching enzyme mimicking in vitro the elongation and branching steps involved in glycogen biosynthesis. Size and molar mass distributions were studied by AF4, coupled with online quasi-elastic light scattering (QELS) and transmission electron microscopy. AF4-MALLS-QELS has shown a remarkable agreement between hydrodynamic radii obtained by online QELS and by AF4 theory in normal mode with constant cross flow. Molar mass, size, and dispersity were shown to significantly increase with initial sucrose concentration, and to decrease when the branching enzyme activity increases. Several populations with different size range were observed: the amount of small size molecules decreasing with increasing sucrose concentration. The spherical and dense global conformation thus highlighted was partly similar to native glycogens. A more detailed study of HBPs synthesized from low and high initial sucrose concentrations was performed using complementary enzymatic hydrolysis of external chains and chromatography. It emphasized a more homogeneous branching pattern than native glycogens with a denser core and shorter external chains. Figure
Characterization of hyperbranched glycopolymers. TEM Transmission electron microscopy. AF4-MALLS-QELS Asymmetrical flow field flow fractionation coupled with multi-angle laser-light scattering and quasi-elastic light scattering 相似文献
54.
Gabrielle M. Risica Veacheslav Vieru Branford O. Wilkins Trevor P. Latendresse Joseph H. Reibenspies Nattamai S. Bhuvanesh Gregory P. Wylie Liviu F. Chibotaru Michael Nippe 《Angewandte Chemie (International ed. in English)》2020,59(32):13335-13340
We report the first f‐block‐ruthenocenophane complexes 1 (Dy) and 2 (Tb) and provide a comparative discussion of their magnetic structure with respect to earlier reported ferrocenophane analogues. While axial elongation of the rare trigonal‐prismatic geometry stabilizes the magnetic ground state in the case of Dy3+ and results in a larger barrier to magnetization reversal (U), a decrease in U is observed for the case of Tb3+. 相似文献
55.
Gabrielle A. Leith Allison M. Rice Brandon J. Yarbrough Anna A. Berseneva Richard T. Ly Charles N. Buck Denis Chusov Amy J. Brandt Donna A. Chen Benjamin W. Lamm Morgan Stefik Kenneth S. Stephenson Mark D. Smith Aaron K. Vannucci Perry J. Pellechia Sophya Garashchuk Natalia B. Shustova 《Angewandte Chemie (International ed. in English)》2020,59(15):6000-6006
The effect of donor (D)–acceptor (A) alignment on the materials electronic structure was probed for the first time using novel purely organic porous crystalline materials with covalently bound two‐ and three‐dimensional acceptors. The first studies towards estimation of charge transfer rates as a function of acceptor stacking are in line with the experimentally observed drastic, eight‐fold conductivity enhancement. The first evaluation of redox behavior of buckyball‐ or tetracyanoquinodimethane‐integrated crystalline was conducted. In parallel with tailoring the D‐A alignment responsible for “static” changes in materials properties, an external stimulus was applied for “dynamic” control of the electronic profiles. Overall, the presented D–A strategic design, with stimuli‐controlled electronic behavior, redox activity, and modularity could be used as a blueprint for the development of electroactive and conductive multidimensional and multifunctional crystalline porous materials. 相似文献
56.
Jennifer C. Rote Sarah N. Malkowski C. Skyler Cochrane Gabrielle E. Bailey Noah S. Brown Mauricio Cafiero 《合成通讯》2017,47(5):435-441
Dopamine is a ubiquitous neurotransmitter essential in the proper functioning of the human body. In addition to this critical role, the catecholamine core has shown utility as a scaffold for numerous drugs and in other applications, like metal detection and adhesive materials. Substituents at the 6-position of dopamine’s catechol core can modulate its stereoelectronic properties, the acidity of its phenolic hydroxyl groups, and the overall hydrophobicity of the molecule. Herein, we report the synthesis of a series of four novel dopamine analogues substituted at the 6-position of catechol core. The 1H NMR chemical shift of the aromatic proton meta to the substituent correlated strongly with the Hammett σm constant, confirming the electronic properties of substituents. 相似文献
57.
Lima Ade F de Moura GF de Lima MA de Souza PM da Silva CA Takaki GM do Nascimento AE 《Molecules (Basel, Switzerland)》2011,16(3):2486-2500
This study concerns the metabolism of polyphosphate in Trichoderma harzianum, a biocontrol agent with innate resistance against most chemicals used in agriculture, including metals, when grown in the presence of different concentrations of cadmium. The biomass production was affected by the concentration of metal used. Control cultures were able to accumulate polyphosphate under the conditions used. Moreover, the presence of cadmium induced a reduction in polyphosphate content related to the concentration used. The morphological/ultrastructural aspects were characterized by using optical and scanning electron microscopy, and were affected by the heavy metal presence and concentration. The efficiency of cadmium removal revealed the potential of the microorganism for use in remediation. The data indicate the potential for polyphosphate accumulation by the fungus, as well as its degradation related to tolerance/survival in the presence of cadmium ions. 相似文献
58.
59.
Stephanie K. Polutchko Gabrielle N. E. Glime Barbara Demmig-Adams 《Molecules (Basel, Switzerland)》2021,26(17)
Prevention of neurodegeneration during aging, and support of optimal brain function throughout the lifespan, requires protection of membrane structure and function. We review the synergistic action of different classes of dietary micronutrients, as well as further synergistic contributions from exercise and stress reduction, in supporting membrane structure and function. We address membrane-associated inflammation involving reactive oxygen species (ROS) that produce immune regulators from polyunsaturated fatty acids (PUFAs) of membrane phospholipids. The potential of dietary micronutrients to maintain membrane fluidity and prevent chronic inflammation is examined with a focus on synergistically acting membrane-soluble components (zeaxanthin, lutein, vitamin E, and omega-3 PUFAs) and water-soluble components (vitamin C and various phenolics). These different classes of micronutrients apparently operate in a series of intertwined oxidation-reduction cycles to protect membrane function and prevent chronic inflammation. At this time, it appears that combinations of a balanced diet with regular moderate exercise and stress-reduction practices are particularly beneficial. Effective whole-food-based diets include the Mediterranean and the MIND diet (Mediterranean-DASH Intervention for Neurodegenerative Delay diet, where DASH stands for Dietary Approaches to Stop Hypertension). 相似文献
60.
We present what is to our knowledge a new method for measuring the relative piston between two independent beams separated by a physical gap, typical of petawatt facilities. The feasibility of this measurement, based on quadriwave lateral shearing interferometry, has been demonstrated experimentally: piston has been measured with accuracy and sensitivity better than 50 nm. 相似文献