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81.
The formation of silica nanostructures by several living organisms, such as diatoms or sponges, involves specific macromolecules that control the growth and the organization of silica nanoparticles. In order to investigate if a single molecular system could perform both particle size control and morphological template, gelatine thin films of various concentration and strength were prepared as biomimetic models and their reactivity towards sodium silicate aqueous solutions was studied. Simultaneous formation of silica particles in the nanometric and micrometric size range was observed. The former corresponds to colloids grown at the surface of the gelatine films and the latter to particles induced by gelatine chain brushes formed at the film/water interface. These results are in good agreement with well-known principles of biomineralization and suggest that multi-molecular systems, rather than single components, are responsible for biogenic silica nanostructure formation.  相似文献   
82.
83.
During our research looking for novel inverse agonists of RORγt, we identified a potent sulfoximine-based modulator as one of our pre-clinical candidates for the topical treatment for psoriasis. Herein, we describe the various routes we evaluated during the lead generation and optimization phases and the final route chosen for scale-up to deliver the first 100?g of API.  相似文献   
84.
Journal of Nanoparticle Research - Nanoparticles form the fundamental building blocks for many exciting applications in various scientific disciplines. However, the problem of the large-scale...  相似文献   
85.
We describe herein the first halogen dance (HD) in continuous flow on 2-chloro-3-bromopyridine by selectively trapping a (pyridin-4-yl)lithium species that is known to undergo the halogen-dance process. In addition, this lithiated intermediate was trapped at lower temperature before the HD occurs. The HD process was extended to fluoro-iodopyridines by using various electrophiles to afford 28 examples with yields ranging from 42 to 97 % with very short residence times. Finally, scale up of the reaction was demonstrated, affording a promising space-time yield (STY) of 4.2 kg.h−1.L−1.  相似文献   
86.
We consider the phase field equations in arbitrary space dimension. We show that the corresponding boundary value problems are well-posed when assuming that the initial data is square integrable and prove the existence of a maximal attractor and of an inertial set.  相似文献   
87.
Measurements of the proton spin lattice relaxation time in all trans and 50% trans undoped polyacetylene are reported. From experimental data at various temperatures (140–300 K) and different frequencies (8–92 MHz), the cut-off frequency and the anisotropy of the one dimensional diffusion mechanism are estimated.  相似文献   
88.
High-spin states in154Er have been populated by bombarding147Sm and148Sm with12C particles. Excitation functions, lifetimes, angular distributions andγ-γ coincidences were measured. AT 1/2=35ns isomeric state atE x~3 MeV has been found and is interpreted as a two-quasi-particle state with aligned angular momenta. A cascade of intense individual lines from states with spin up to at least 26 (excitation energy up to 8.543 MeV) was found to feed the isomeric state. The level sequence above this yrast trap exhibits an irregular pattern which cannot be easily interpreted in terms of collective modes.  相似文献   
89.
We have measured the X-ray multiplicities of the transitions deexciting the quasi-continuum region as a function of the input spin for deformed and transitional erbium isotopes obtained in (40Ar,xn) reactions. Combined withγ-ray angular distribution studies, these measurements clearly show the occurrence of a magnetic dipole component in the energy region 300–800keV. The spin dependence of this “bump” is quite different in deformed and transitional nuclei. In the latter case, a sudden increase in the quasi-continuumK electron multiplicity arises for spins higher than 35? and is strongly correlated to the occurrence of collective modes in these nuclei at the same spins. It is suggested to correspond to collective behavior of bands built on yrast states of single particle nature.  相似文献   
90.
The classical Haar construction of Brownian motion uses a binary tree of triangular wedge-shaped functions. This basis has compactness properties which make it especially suited for certain classes of numerical algorithms. We present a similar basis for the Ornstein-Uhlenbeck process, in which the basis elements approach asymptotically the Haar functions as the index increases, and preserve the following properties of the Haar basis: all basis elements have compact support on an open interval with dyadic rational endpoints; these intervals are nested and become smaller for larger indices of the basis element, and for any dyadic rational, only a finite number of basis elements is nonzero at that number. Thus the expansion in our basis, when evaluated at a dyadic rational, terminates in a finite number of steps. We prove the covariance formulae for our expansion and discuss its statistical interpretation. Electronic Supplementary Material  The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   
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