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91.
K. N. Houk Pierluigi Caramella Linda L. Munchausen Yau-Min Chang Arturo Battaglia Joyner Sims D. C. Kaufman 《Journal of Electron Spectroscopy and Related Phenomena》1977,10(4):441-454
The photoelectron spectra of five nitrones—N-t-butyl-, C-phenyl-N-methyl-, C-phenyl-N-t-butyl-, C-mesityl-N-methyl-nitrone and dihydroisoquin 相似文献
92.
93.
This article identifies six social-science research methodologies that will be useful for charting the sociocultural meaning of nanotechnology: web-based questionnaires, vignette experiments, analysis of web linkages, recommender systems, quantitative content analysis, and qualitative textual analysis. Data from a range of sources are used to illustrate how the methods can delineate the intellectual content and institutional structure of the emerging nanotechnology culture. Such methods will make it possible in future to test hypotheses such as that there are two competing definitions of nanotechnology – the technical-scientific and the science-fiction – that are influencing public perceptions by different routes and in different directions. 相似文献
94.
A.G. Gonzalez J. Darias J.D. Martín C. Pérez J.J. Sims G.H.Y. Lin R.M. Wing 《Tetrahedron》1975,31(19):2449-2452
The halogenated sesquiterpene isocaespitol (1) has been isolated from the marine alga Laurencia caespitosa Lamx and its structure determined by X-ray crystallography. 相似文献
95.
We have developed a strategy using ultraviolet light to polymerize mixed monomer solutions onto the surface of a poly(dimethylsiloxane) (PDMS) microdevice. By including monomers with different chemical properties, electrophoretic separations were optimized for a test set of analytes. The properties of surfaces grafted with a single neutral monomer, a neutral and a negative monomer, or a neutral, negative, and cross-linking monomer were assessed. The highest quality separations were achieved in channels with cross-linked coatings. The separation efficiency for biologically relevant peptides (kinase substrates) on these surfaces was as high as 18 600 theoretical plates in a 2.5 cm channel. The test peptides were fluorescein-AEEEIYGEFEAKKKK, fluorescein-GRPRAATFAEG, fluorescein-GRPRAA(T-PO(3))FAEG, fluorescein-DLDVPIP GRFDRRVSVAAE, and fluorescein-DLDVPIPGRFDRRV(S-PO(3))VAAE. Separations between two different peptides occurred in as little as 400 ms after injection into the separation channel. The simultaneous separation of five kinase and phosphatase substrates was also demonstrated. By carefully selecting mixtures of monomers with the appropriate properties, it may be possible to tailor the surface of PDMS for a large number of different electrophoretic separations. 相似文献
96.
A simple, rapid and sensitive method for the determination of psilocin and psilocybin is described. This is the first report on the determination of psilocin and psilocybin using flow injection analysis with acidic potassium permanganate and tris(2,2′-bipyridyl)ruthenium(II) chemiluminescence. The limits of detection (signal-to-noise ratio = 3) are 9 × 10−10 M and 3 × 10−10 M for psilocin and psilocybin, respectively.A concise synthetic route for psilocin in three steps from readily available starting materials is also described. The structures were elucidated on the basis of spectroscopic data. 相似文献
97.
98.
D. J. Sims W. S. Andrews K. A. M. Creber X. Wang 《Journal of Radioanalytical and Nuclear Chemistry》2005,263(3):619-623
Summary In 1951, 6.7 liters of an aqueous acidic solution of irradiated uranium (360 GBq) leaked from a buried storage tank into unsaturated prairie soil, where it has remained, undisturbed. In October 2001, sonic drilling was conducted to recover core samples around and below the tank location. This paper describes the measurements and investigative approaches being pursued to determine the transport properties of the various fission and daughter products and actinides. Separate effects laboratory experiments are also being conducted involving both inert and radioactive samples in similar soil, to examine the effects on transport properties (diffusion and sorption) of temperature, recharge and discharge rates, concentration and soil porosity. Finally, transport modeling approaches are discussed. 相似文献
99.
We consider the Deaconu–Renault groupoid of an action of a finitely generated free abelian monoid by local homeomorphisms of a locally compact Hausdorff space. We catalogue the primitive ideals of the associated groupoid C ?-algebra. For a special class of actions we describe the Jacobson topology. 相似文献
100.
Hazrat Roozbeh Pask David Sierakowski Adam Sims Aidan 《Algebras and Representation Theory》2021,24(4):877-909
Algebras and Representation Theory - We introduce an algebraic version of the Katsura C?-algebra of a pair A,B of integer matrices and an algebraic version of the Exel–Pardo... 相似文献