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The reaction of primary aromatic amines with aryl aldehydes is found to be catalyzed by cerium chloride heptahydrate under solvent-free conditions to give the corresponding Schiff bases in good yields. 相似文献
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RITVA LINDBERG GORAN SUNDHOLM JOHAN SJö BLOM PETRI AHONEN ESKO I. KAUPPINEN 《Journal of Dispersion Science and Technology》2013,34(1-2):715-722
The zeta-potentials of silica, copper, platinum and gold particles have been measured as a function of pH. The isoelectric points were found to be at pH 3.0, 5.8, 3.0 and 3.5, respectively. In the pH range 3.0 to 5.8 copper and silica particles are oppositely charged and accordingly the coating of silica with copper particles could be demonstrated. In the case of gold and platinum the sign of the charge is such that direct adhesion to silica particles cannot be expected and this was also demonstrated in the case of platinum. 相似文献
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van Enk SJ 《Physical review letters》2000,84(4):789; author reply 790
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Douglas McHugh Sherry SJ Hu Neta Rimmerman Ana Juknat Zvi Vogel J Michael Walker Heather B Bradshaw 《BMC neuroscience》2010,11(1):44
Background
Microglia provide continuous immune surveillance of the CNS and upon activation rapidly change phenotype to express receptors that respond to chemoattractants during CNS damage or infection. These activated microglia undergo directed migration towards affected tissue. Importantly, the molecular species of chemoattractant encountered determines if microglia respond with pro- or anti-inflammatory behaviour, yet the signaling molecules that trigger migration remain poorly understood. The endogenous cannabinoid system regulates microglial migration via CB2 receptors and an as yet unidentified GPCR termed the 'abnormal cannabidiol' (Abn-CBD) receptor. Abn-CBD is a synthetic isomer of the phytocannabinoid cannabidiol (CBD) and is inactive at CB1 or CB2 receptors, but functions as a selective agonist at this Gi/o-coupled GPCR. N-arachidonoyl glycine (NAGly) is an endogenous metabolite of the endocannabinoid anandamide and acts as an efficacious agonist at GPR18. Here, we investigate the relationship between NAGly, Abn-CBD, the unidentified 'Abn-CBD' receptor, GPR18, and BV-2 microglial migration. 相似文献7.
Here we report the results of combined powder X-ray and neutron diffraction studies of Bi4?x Nd x Ti3O12 (0.0 ≤ x ≤ 2.0) compositions. The parent Bi4Ti3O12 has an orthorhombic lattice (space group: B2cb) with unit cell parameters a = 5.4432(5) Å, b = 5.4099(5) Å and c = 32.821(2) Å, and V = 966.5(1) Å3. This orthorhombic lattice is retained in all the studied compositions. The unit cell parameters gradually decrease with Nd3+ ion concentration with a discontinuity at x = 0.75. Orthorhombicity of the lattice decreases with increase in Nd3+ content in the lattice. The orthorhombic unit cell parameters for a representative Bi2Nd2Ti3O12 composition are: a = 5.3834(9), b = 5.3846(9) and c = 32.784(1) Å. The observed orthorhombic distortion at x = 2.0 is very small and thus the crystal structure apparently has a pseudo-tetragonal lattice. In addition, Nd3+ preferentially substitutes in the perovskite slab of the Aurivillius structure. The fraction of Nd3+ in the fluorite slab increases with increase in Nd3+ contents. 相似文献
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S. N. Achary O. D. Jayakumar S. J. Patwe A. B. Shinde P. S. R. Krishna S. K. Kulshreshtha A. K. Tyagi 《Pramana》2008,71(5):941-946
Herein we report the results of detailed crystallographic studies of Ca1−x
Ba
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Zr4P6O24 compositions from combined Rietveld refinements of powder X-ray and neutron diffraction data. All the studied compositions
crystallize in rhombohedral lattice (space group R-3 No. 148). A continuous solid solution is concluded from the systematic
variation of unit cell parameters. The variation of unit cell parameters with the composition indicates decreasing trend in
a parameter with increasing Ba2+ concentration contrast to an increasing trend in c parameter.
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