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991.
AnL
1-existence theorem is proved for the nonlinear stationary Boltzmann equation with hard forces and no small velocity truncation—only
the Grad angular cut-off-in a setting between two coaxial rotating cylinders when the indata are given on the cylinders. 相似文献
992.
993.
The effectiveness of stabilisers, organic (hindered amine light stabilisers), inorganic (nanoparticulate zinc oxide), and combinations thereof, in preventing the signatures of degradation in polypropylene subjected to accelerated weathering is studied. Not only the type of stabiliser but also its distribution is important for stabiliser efficiency. The spatial effects of stabilization are studied using positron spectroscopy depth profiling. 相似文献
994.
Anne Hansen 《BMC neuroscience》2007,8(1):64
Background
The nasal cavity of all vertebrates houses multiple chemosensors, either innervated by the Ist (olfactory) or the Vth (trigeminal) cranial nerve. Various types of receptor cells are present, either segregated in different compartments (e.g. in rodents) or mingled in one epithelium (e.g. fish). In addition, solitary chemosensory cells have been reported for several species. Alligators which seek their prey both above and under water have only one nasal compartment. Information about their olfactory epithelium is limited. Since alligators seem to detect both volatile and water-soluble odour cues, I tested whether different sensory cell types are present in the olfactory epithelium. 相似文献995.
Micha?l?Canipelle Sébastien?Tilloy Anne?Ponchel Hervé?Bricout Eric?MonflierEmail author 《Journal of inclusion phenomena and macrocyclic chemistry》2005,51(1-2):79-85
Interactions between the meta-substituted monosulfonated triphenylphosphine and chemically modified β-cyclodextrins were investigated in aqueous solution by NMR and UV–vis spectroscopy. Titration and continuous variation plots obtained from 31P NMR data indicate that the monosulfonated triphenylphosphine forms 1:1 inclusion complexes with the 2-hydroxypropylated β-cyclodextrin, the methylated β-cyclodextrin and the (2-hydroxy-3-trimethylammoniopropyl)-β-cyclodextrin chloride. These inclusion complexes are more stable that those formed with native β-cyclodextrin, confirming that poisoning of the chemically modified β-cyclodextrins by the hydrosoluble phosphine occurs when modified cyclodextrins are used as mass transfer promoters in aqueous-phase organometallic catalysis.This revised version was published online in July 2005 with a corrected issue number. 相似文献
996.
997.
Naban-Maillet J Lesage D Bossée A Gimbert Y Sztáray J Vékey K Tabet JC 《Journal of mass spectrometry : JMS》2005,40(1):1-8
Internal energies and energy distributions were studied using the 'survival yield' method developed previously. In addition to conventional benzylpyridinium salts, protonated esters (fragmenting by rearrangement) and protonated leucine enkephalin were also used, extending the validity of the technique. Fragmentation processes were studied in the cone voltage region and modeled by the RRKM-based MassKinetics program. The results show that the shapes of the energy distributions are similar to thermal distributions. The mean internal energies are very similar for all compound classes studied, and show a linear increase with collision energy in the 10-50 eV region. 相似文献
998.
Michael?Y?Chao Jonah?Larkins-Ford Tim?M?Tucey Anne?C?HartEmail author 《BMC neuroscience》2005,6(1):45
Background
Notch signaling pathways are conserved across species and traditionally have been implicated in cell fate determination during embryonic development. Notch signaling components are also expressed postdevelopmentally in the brains of adult mice and Drosophila. Recent studies suggest that Notch signaling may play a role in the physiological, rather than developmental, regulation of neurons. Here, we investigate a new non-developmental role for Caenorhabditis elegans lin-12 Notch signaling in neurons regulating the spontaneous reversal rate during locomotion. 相似文献999.
G. Farés R. Bimbot S. Hachem M. Mirea R. Anne T. Benfoughal C. Cabot F. Clapier P. Delbourgo-Salvador T. Ethvignot A. Lefebvre M. Lewitowicz P. Roussel-Chomaz M. G. Saint-Laurent J. E. Sauvestre J. L. Sida Yang Yong Feng 《The European Physical Journal A - Hadrons and Nuclei》2004,19(1):105-116
The fragmentation of 95 MeV/u 12C and 75 MeV/u 13C projectiles, interacting with natural targets of different elements (9Be,
Cu and 197Au for 12C, and 9Be,
Ni, and 181Ta for 13C) and of various thicknesses has been investigated at GANIL, using the doubly achromatic magnetic spectrometer LISE. The projectile-like fragments transmitted at 0
have been analysed using a silicon
-E telescope and the
-time-of-flight method. The results obtained with the thinnest targets are discussed in the scope of radioactive nuclear beam production. The fragment momentum distributions can be fitted by Gaussian peaks associated with exponential tails towards low momentum values. The experimental production yields are compared with the results of the simulation code LISE. It appears that this code reproduces satisfactorily the yields of nuclei close to the stability line, but strongly overestimates the production of very neutron-deficient nuclei.Received: 17 September 2002, Revised: 25 July 2003, Published online: 18 December 2003PACS:
25.70.Mn Projectile and target fragmentation - 29.90. + r Other topics in elementary-particle and nuclear physics experimental methods and instrumentation 相似文献
1000.
The properties of a silver atom in bulk water were studied for the first time by molecular dynamics simulations using two complementary mixed quantum-classical approaches. The first one consists of treating by quantum mechanics one electron only, which interacts with a classical silver cation and solvent through one-electron pseudopotentials. The second one is Car-Parrinello molecular dynamics that treats all the valence electrons quantum-mechanically. Very good agreement is obtained between these two methods, and the calculated absorption spectrum of the solvated silver atom agrees very well with experimental data. Both simulations reveal that the silver atom is in the critical region for the appearance of a dipolar excitonic state and exhibits a dipole moment of approximately 2 D with large fluctuations of +/-1 D. The structure of the solvation shell is also analyzed. 相似文献