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1.
Jérôme Gualbert Patrick Shahgaldian Adina Lazar Anthony W. Coleman 《Journal of inclusion phenomena and macrocyclic chemistry》2004,48(1-2):37-44
Solid Lipid Nanoparticles (SLNs) have been prepared fromc-2,c-8,c-14,c-20-tetraundecyl-4,6,10,12,16,18,22,24-octahydroxyresorc[4]areneas colloidal suspensions. Photon Correlation Spectroscopy studies revealed aparticle hydrodynamic diameter of 150 nm. Non-contact mode Atomic ForceMicroscopy allows observation of the particles as slightly flattened sphericalobjects of 236 (±40) nm diameter and 145 (±40) nm height. Thestudy of the preparation parameters showed that shear force does not affectthe hydrodynamic size of the SLNs. In contrast, the viscosity and the pH ofthe aqueous phase, the amphiphile concentration in the organic phase and thevolume of organic phase used, all lead to variation in the size of the particles.In term of post preparation parameters only the ionic strength has been shownto affect significantly the particle size; while the pH of the storing solution,microwave, ultrasonic and thermal treatments do not. Short and long-termstability studies have been performed to measure the effect of the ionic strengthon the stability of the particles. The use of carbohydrate cryoprotectants does notallow re-dispersion of the colloidal suspension after freeze-drying. 相似文献
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Patterson JR Barker A Briere RA Gibbons LK Makoff G Papadimitriou V Somalwar S Wah YW Winstein B Winston R Woods M Yamamoto H Swallow E Bock GJ Coleman R Enagonio J Hsiung YB Stanfield K Stefanski R Yamanaka T Blair G Gollin GD Karlsson M Okamitsu JK Tschirhart R Brisson JC Debu P Peyaud B Turlay R Vallage B 《Physical review letters》1990,64(13):1491-1494
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Anthony W. Coleman C. Mitchell Means Simon G. Bott Jerry L. Atwood 《Journal of chemical crystallography》1990,20(2):199-201
[NBu4][Br3] interacts with C6H6 to form an air-stable liquid clathrate. The tribromide anion reacts with phenol to give para-bromophenol in>95% yield. The HBr which is generated in the reaction combines with the Br– anion to form [Br-H-Br]–. The latter forms the basis for a new liquid clathrate, [NBu4][Br-H-Br]·n C6H6. The parent salt, [NBu4][Br3], crystallizes in the monoclinic space group C2/c witha=12.983(5),b=10.380(7),c=16.222(6) Å,=93.93(3)°, andD
c
=1.47 g cm–3 forZ=4. The final R value is 0.068 based on 787 observed reflections. 相似文献
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We study the ultraviolet behavior of two dimensional supersymmetric non-linear -models with target space an arbitrary Kähler manifoldM, so that the models areN=2 supersymmetric. We point out that these models have an additional fermionic axial symmetry if and only if the metric onM is Ricci flat. We show that the preservation of this symmetry in perturbation theory implies that both bare and renormalized metrics onM are Ricci flat. Combining this result with the constraint ofN=2 supersymmetry requiring that all counter-terms to the metric beyond one-loop order be cohomologically trivial, we argue thatN=2 models defined on Ricci flat Kähler manifolds are on-shell ultraviolet finite to all orders of perturbation theory. 相似文献
10.
Total synthesis of lucilactaene, a cell cycle inhibitor active in p53-inactive cells 总被引:2,自引:0,他引:2
Coleman RS Walczak MC Campbell EL 《Journal of the American Chemical Society》2005,127(46):16038-16039
Hetero-bis-metalated 1,3-butadiene is employed in the lynchpin coupling of synthetic fragments of the side chain of the antitumor agent, lucilactaene. Sequential Stille and Suzuki-Miyaura couplings interpolate this unique boron/tin diene into the pentaene chain. The total synthesis of lucilactaene was accomplished efficiently, in just eight linear steps. 相似文献