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1.
Laura Bader Nicola Durante Maska Law Guglielmo Lunardon Tim Penttila 《Designs, Codes and Cryptography》2003,29(1-3):41-50
We do the tentative beginnings of a study of BLT-sets of generalised quadrangles via their symmetries. In particular, the study of whorls about a line leads us to hyperbolic reflections preserving a BLT-set of Q(4, q). 相似文献
2.
Alick KT Law Deepak Gupta Shawn Levy Douglas C Wallace Robert J McKeon Charles R Buck 《BMC neuroscience》2004,5(1):1
Background
The adenine nucleotide translocator 1 (Ant1) is an inner mitochondrial membrane protein involved with energy mobilization during oxidative phosphorylation. We recently showed that rodent Ant1 is upregulated by transforming growth factor-beta (TGF-β) in reactive astrocytes following CNS injury. In the present study, we describe the molecular mechanisms by which TGF-β1 regulates Ant1 gene expression in cultured primary rodent astrocytes. 相似文献3.
Dendritic nanowire ultraviolet laser array 总被引:16,自引:0,他引:16
Yan H He R Johnson J Law M Saykally RJ Yang P 《Journal of the American Chemical Society》2003,125(16):4728-4729
Self-organized dendritic crystal growth is explored to assemble uniform semiconductor nanowires into highly ordered one-dimensional microscale arrays that resemble comb structures. The individual ZnO nanowires have uniform diameters ranging from 10 to 300 nm. They are evenly spaced on a stem with a regular periodicity of 0.1-2 micrometer. Under optical excitation, each individual ZnO nanowire serves as a Fabry-Perot optical cavity, and together they form a highly ordered nanowire ultraviolet laser array. 相似文献
4.
MM. J. Duflos D. Letouz G. Queguiner P. Pastour 《Journal of heterocyclic chemistry》1973,10(6):1083-1084
This communication describes the synthesis of l-methyl-2,3-diformylpyrrole. This new compound is used to prepare a new heterocycle, l-methylcyclohepta[b]pyrrol-6-one and thus allows a new synthesis of l-methylpyrrolo[2,3-d]pyridazine. 相似文献
5.
The quantum density of states of the Henon-Heiles potential displays a pronounced beating pattern. This has been explained by the interference of three isolated classical periodic orbits with nearby actions and periods. A singular magnetic flux line, passing through the origin, drastically alters the beats even though the classical Lagrangian equations of motion remain unchanged. Some of the changes can be easily understood in terms of the Aharonov-Bohm effect. However, we find that the standard periodic orbit theory does not reproduce the diffraction-like quantum effects on those classical orbits which intersect the singular flux line, and argue that corrections of relative order variant Planck's over 2pi are necessary to describe these effects. We also discuss the changes in the distribution of nearest-neighbor spacings in the eigenvalue spectrum, brought about by the flux line. (c) 1995 American Institute of Physics. 相似文献
6.
A new fusion agent is proposed for the analysis of cement and cement raw meal using AAS. In the described method, 0.8 g of the fusion agent, consisting of equal portions of oxalic acid, lithium carbonate and lithium tetraborate, was mixed with 0.2 g of the sample, and the mixture was fused for 10 min at 925 degrees C in a platinum crucilbe. The fusion cake was dissolved with dilute hydrochloric acid (1 + 10) and diluted to 500 ml for the determination of Si, Al, Fe, Ti, Na and K expressed as SiO(2), Al(2)O(3), Fe(2)O(3), TiO(2), Na(2)O, and K(2)O respectively. For the determination of Ca and Mg (expressed as CaO and MgO respectively), 10 ml of the previous sample solution were mixed with 4 ml of 6% (m/v) lanthanum nitrate solution and the solution was diluted to 100 ml. The method was found to have good accuracy and precision. The time required to determine the eight elements was around 80 min for each sample. 相似文献
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The preparation and use of a polystyrene-supported poly(maleic anhydride) resin for the preconcentration of lead from tapwater samples is described. After elution with dilute nitric acid, lead is determined by flame atomic absorption spectrometry down to levels well below the 50 ng cm-3 E.E.C. limit. 相似文献