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131.
Charles W. Bauschlicher Stephen P. Walch Harry Partridge 《Chemical physics letters》1984,103(4):291-295
The electron affinity (EA) of the Cu atom is computed using large STO and GTO basis sets at several levels of correlation. The best computed value is 1 相似文献
132.
Stephen D. Cohen 《Designs, Codes and Cryptography》1992,2(2):169-174
For a finite field GF(q) of odd prime power order q, and n 1, we construct explicitly a sequence of monic irreducible reciprocal polynomials of degree n2
m
(m = 1, 2, 3, ...) over GF(q). It is the analog for fields of odd order of constructions of Wiedemann and of Meyn over GF(2). We also deduce iterated presentations of GF (q
n
2). 相似文献
133.
Stephen J. Summers 《Communications in Mathematical Physics》1982,86(1):111-141
We present sufficient conditions that imply duality for the algebras of local observables in all Abelian sectors of all locally normal, irreducible representations of a field algebra if twisted duality obtains in one of these representations. It is verified that the Yukawa2 model satisfies these conditions, yielding the first proof of duality for the observable algebra in all coherent charge sectors in this model. This paper also constitutes the first verification of the assumptions of the axiomatic study of the structure of superselection sectors by Doplicher, Haag and Roberts in an interacting model with nontrivial sectors. The existence of normal product states for the free Fermi field algebra and, thus, the verification of the funnel property for the associated net of local algebras are demonstrated. 相似文献
134.
The novel ylides (II) and (III) have been obtained treatment of perfluoro-1-azacyclohexene and perfluoro-2-azapropene, respectively, with -iminopyridinium ylide (I) generated from -aminopyridinium iodide and anhydrous potassium carbonate in methylene chloride. A mixture of the -triazolo[1,5-]pyridine (IV) and a compound thought to be its dihydro-analogue (V) were isolated following attack on perfluoroacetonitrile by the parent ylide (I); the former product was also prepared by heating 1,2-diamino-pyridinium iodide with trifluoroacetic anhydride. 相似文献
135.
The cationic ruthenium complexes [(η5-C5H5)Ru(Ph2PCH2CH2PPh2)L]PF6 (L=olefin, CO, pyridine or acetonitrile) have been prepared by treatment of (η5-C5H5)Ru(Ph2PCH2CH2PPh2)Cl with L and NH4PF6 in methanol of 20°C. 相似文献
136.
Stidder B Fragneto G Roser SJ 《Langmuir : the ACS journal of surfaces and colloids》2005,21(20):9187-9193
The effect of the addition of 1, 2, 4, and 6 mol % cholesterol to 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) floating bilayers has been investigated by neutron reflectivity. All samples exhibited fully stable and reversible gel and fluid phases. Around the main lipid phase transition temperature, DPPC double bilayers exhibit large increases in the water layer separating the bilayers and the upper bilayer roughness. The inclusion of low amounts of cholesterol reduced the swelling of the water layer between the bilayers and the upper bilayer roughness and progressively widened the temperature range over which swelling occurs. Results from asymmetric bilayers are also reported. A higher amount of cholesterol in the lower bilayer induces a smaller swelling of the water layer between the bilayers than in the symmetric case. Finally, the effect of the inclusion of a leaflet of 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE) was investigated. The presence of a leaflet with a higher gel-transition temperature (T(m)) modifies the phase behavior of the lower T(m) leaflet. 相似文献
137.
[reaction: see text] An enantioselective entry to the skeleton of the tremulane sesquiterpenes is described. The approach features a series of efficient transition metal-catalyzed reactions commencing with an enantioselective rhodium(II)-catalyzed intramolecular cyclopropanation followed by a regioselective allylic alkylation and a diastereoselective rhodium(I)-catalyzed [5 + 2] cycloaddition. This strategy was applied to the first enantioselective syntheses of tremulenediol A and tremulenolide A. 相似文献
138.
α-Oxo-carboxylic acids undergo photo-oxidative decarboxylation from both C-1 and C-2 positions, and reaction does not involve singlet oxygen: a mechanism involving an electron transfer reaction is postulated. 相似文献
139.
We report a novel source of tunable, coherent radiation in the vacuum ultraviolet, which use resonantly enhanced difference-frequency mixing in xenon gas Efficiencies are high (o.4%) at modest input laser intensities. With existing dye lasers the range of tunability will span the 152–200 nm region. 相似文献
140.
Stephen Pierce 《Journal of Geometry》1981,16(1):30-40
Let V be an n-dimensional regular quadratic space over a field K of characteristic not 2. Assume n 4. Let W be a regular hyperplane and v a nonzero vector orthogonal to W. Suppose every regular hyperplane in W is universal. If is an isometry of V not leaving W invariant, then , together with the isometries of W, generate the orthogonal group of V, with one exception.The work of the author was partially supported by NSERC Grant A-7862. 相似文献