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101.
Application-specific optimization of disordered nanoporous carbons remains a formidable challenge due to the difficulty in
accurately characterizing their microstructures with current empirical methods. Using molecular simulation techniques, we
investigated the adsorptive and diffusive behavior of argon in three models of disordered nanoporous carbons. We found that
the structural and morphological differences between these models gave rise to distinct phenomenological properties. The adsorptive
behavior of argon in both the low and high pressure regimes was enhanced dramatically in the models with more crystalline
microstructures. As for dynamic properties, we found that the adsorbent’s structure and energetic topology significantly alters
the rates of diffusion as well as the characteristics of the underlying diffusion mechanisms. 相似文献
102.
103.
Synthetic studies toward eletefine, a novel stephaoxocane alkaloid, were undertaken in an attempt to provide a general methodology to aid in the synthesis of other novel stephaoxocanes. An efficient construction of the AB ring system with increased functionality is described which presents a flexible approach to synthesizing the C and D rings of eletefine. 相似文献
104.
105.
106.
Jeremy Bernstein 《Physics in Perspective (PIP)》2010,12(1):36-50
I discuss the origin of the idea of making a fusion (hydrogen) bomb and the physics involved in it, and then turn to the design
proposed for one by the unlikely collaborators John von Neumann and Klaus Fuchs in a patent application they filed at Los
Alamos in May 1946, which Fuchs passed on to the Russians in March 1948, and which with substantial modifications was tested
on the island of Eberiru on the Eniwetok atoll in the South Pacific on May 8, 1951. This test showed that the fusion of deuterium
and tritium nuclei could be ignited, but that the ignition would not propagate because the heat produced was rapidly radiated
away. Meanwhile, Stanislaw Ulam and C.J. Everett had shown that Edward Teller’s Classical Super could not work, and at the
end of December 1950, Ulam had conceived the idea of super compression, using the energy of a fission bomb to compress the
fusion fuel to such a high density that it would be opaque to the radiation produced. Once Teller understood this, he invented
a greatly improved, new method of compression using radiation, which then became the heart of the Ulam–Teller bomb design,
which was tested, also in the South Pacific, on November 1, 1952. The Russians have freely acknowledged that Fuchs gave them
the fission bomb, but they have insisted that no one gave them the fusion bomb, which grew out of design involving a fission
bomb surrounded by alternating layers of fusion and fission fuels, and which they tested on November 22, 1955. Part of the
irony of this story is that neither the American nor the Russian hydrogen-bomb programs made any use of the brilliant design
that von Neumann and Fuchs had conceived as early as 1946, which could have changed the entire course of development of both
programs. 相似文献
107.
108.
In this paper we study continuous representations of locally -analytic groups in locally convex -vector spaces, where is a finite extension of and is a spherically complete nonarchimedean extension field of . The class of such representations includes both the smooth representations of Langlands theory and the finite dimensional algebraic representations of , along with interesting new objects such as the action of on global sections of equivariant vector bundles on -adic symmetric spaces. We introduce a restricted category of such representations that we call ``strongly admissible' and we show that, when is compact, our category is anti-equivalent to a subcategory of the category of modules over the locally analytic distribution algebra of . As an application we prove the topological irreducibility of generic members of the -adic principal series for . Our hope is that our definition of strongly admissible representation may be used as a foundation for a general theory of continuous -valued representations of locally -analytic groups.
109.
Griffin JL Nicholls AW Keun HC Mortishire-Smith RJ Nicholson JK Kuehn T 《The Analyst》2002,127(5):582-584
The application of a 1 mm TXI (1H/13C/15N) microlitre NMR probe with z-gradient for metabolic profiling of biofluids is described. The probe was used to provide spectral profiles for rat blood plasma using only approximately 2 microl of fluid with a range of solvent suppression techniques. Using a similar amount of fluid, spectra were obtained from rat and mouse cerebrospinal fluid, demonstrating that the probe could be used to profile rodents metabolically via biofluids previously inaccessible to NMR analysis without the need for termination. 相似文献
110.
A cyclic porphyrin tetramer, consisting of two bis-phosphine substituted zinc(II) porphyrin units and two Rh(III)TPP units, is selected and amplified virtually quantitatively from a dynamic combinatorial library using 4,4'-bipy as a scaffold and using orthogonal binding modes. 相似文献