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41.
A. Martinez A. Queijeiro D. M. Tun 《Zeitschrift fur Physik C Particles and Fields》1995,66(4):607-611
We study the production process
, where
is a proton (antiproton), allowing an anomalous weak magnetic dipole moment parameter
Z
in the ZWW vertex. We compute the pairWZ mass invariant, and total cross section production for various values of
Z
. 相似文献
42.
Luis A. Caffarelli Cristian E. Gutié rrez 《Transactions of the American Mathematical Society》1996,348(3):1075-1092
In this paper we consider a family of convex sets in , , , , satisfying certain axioms of affine invariance, and a Borel measure satisfying a doubling condition with respect to the family The axioms are modelled on the properties of the solutions of the real Monge-Ampère equation. The purpose of the paper is to show a variant of the Calderón-Zygmund decomposition in terms of the members of This is achieved by showing first a Besicovitch-type covering lemma for the family and then using the doubling property of the measure The decomposition is motivated by the study of the properties of the linearized Monge-Ampère equation. We show certain applications to maximal functions, and we prove a John and Nirenberg-type inequality for functions with bounded mean oscillation with respect to
43.
The synthesis, characteristics and analytical reactions of di-2-pyridyl ketone thiosemicarbazone are described. This compound reacts with iron(II) (λmax=410mm, ε = 9.3 · 103 1 mol?1 cm?1), nickel(II) (λmax =395 mm ε =19.6·103 10 mol ?1 cm -1), cobalt(II) (λmax = 415 nm. ε = 1.0 · 104 mol?1 cm?1 ) and copper(I) (λmax =395mm ε = 11.3 · 103 mol?1 cm?1) A critical comparison of di-2-pyridyl ketone, picolinaldehyde and bipyridylglyoxal thiosemicarbazones as analytical reagents is given. 相似文献
44.
E. I. Klimova E. A. Vazquez Lopez T. Klimova M. Martinez Garcia N. N. Meleshonkova L. Ruiz Ramirez 《Russian Journal of General Chemistry》2004,74(12):1830-1835
Monocyclic 3- and 5-ferrocenyl-4,5-dihydropyrazoles with a free NH group in the molecule react with acetylacetone to form the corresponding enaminocarbonyl compounds. The latter were isolated as a single isomer, presumably E. 3-Ferrocenyldihydropyrazoles and 5-ferrocenyl-3-(p-methoxyphenyl)-4,5-dihydropyrazole analogously react with acetoacetic ester. 5-Ferrocenyl-3-phenyl-, 3-(p-bromophenyl)-5-ferrocenyl, and 3,5-diferrocenyl-4,5-dihydropyrazoles react with acetoacetic ester to form acetoacetylpyrazolides.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 12, 2004, pp. 1942–1947.Original Russian Text Copyright © 2004 by E. Klimova, Vazquez Lopez, T. Klimova, Martinez Garcia, Meleshonkova, Ruiz Ramirez.This revised version was published online in April 2005 with a corrected cover date. 相似文献
45.
Poly(ethylene glycol) (PEG 3400) was used as a soluble polymeric support for the synthesis of a series of novel benzazepines. The key step for the preparation of these heterocycles was a phosphine-free palladium-catalyzed Heck reaction. Palladium nanoparticles formed during the course of the reaction were characterized. The presence of PEG 3400 influenced the outcome of the reaction in terms of selectivity. 相似文献
46.
Guarise C Pasquato L Scrimin P 《Langmuir : the ACS journal of surfaces and colloids》2005,21(12):5537-5541
Aqueous solutions of Au colloids (12 +/- 4 nm size) when treated with a blend of mono- and dithiols aggregate forming stable clusters, as evidenced by the shift of their surface plasmon (SP) band from 512 to ca. 600 nm. The presence of carboxylate ester functions on the dithiol allows its cleavage by addition of a cleaving agent, such as hydrazine. The cleavage process results in the breaking down of the clusters of nanoparticles and the shift of the SP band back to lower wavelengths. Further addition of dithiol causes the formation of the clusters again. The aggregation/deaggregation process may be monitored visually by following the color change from pink-red to purple and vice versa in the forward and backward steps, respectively. 相似文献
47.
R. F. B. Serpa E. F. O. De Jesus M. J. Anjos R. T. Lopes M. G. T. do Carmo S. Moreira M. S. Rocha A. M. B. Martinez 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(3):647-652
Summary The study of trace element levels is of great importance due to their relevance in agingand several neurodegenerative diseases.
This work compares the elemental concentrations in different postnatal ages and between the temporal cortex, entorhinal cortex
and hippocampus from Wistar rats, using X-ray total reflection fluorescence with synchrotron radiation. Ten elements were
determined in brain samples: Ti, Cr, Mn, Fe, Cu, Zn, (at trace level) and P, S, Cl and K (at major levels). The elements that
increased with aging in cortical areas were: S, K, Fe, Cu and Zn. Ca and Zn levels decreased with advancing age in the hippocampus.
In addition to this, Ti, Mn and Fe levels were more conspicuous in the entorhinal cortex. 相似文献
48.
Ab initio ground state potential energy surfaces are obtained from interaction energies calculated with the coupled cluster singles and doubles model including connected triples corrections [CCSD(T)] and the aug-cc-pVXZ (X=5,Q,T,D) basis sets augmented with two different sets of midbond functions (denoted 33221 and 33211). The aug-cc-pV5Z-33221 surface is characterized by a T-shaped 49.5 cm(-1) minimum at Re=3.38 Angstroms and a linear saddle point at 3.95 Angstroms with De=36.6 cm(-1). These results agree well with the values provided by the accurate semiempirical potentials available. The rovibronic spectroscopic properties are determined and compared to the available experimental data and previous theoretical results. We study the basis set convergence of the intermolecular potentials and the rotational frequencies. The aug-cc-pVTZ basis sets provide reasonable binding parameters, but seem not to be converged enough for the evaluation of the microwave spectra. The aug-cc-pVQZ basis sets considerably improve the triple zeta results. The differences between the results obtained with the aug-cc-pVTZ-33221 basis set surface and those with the aug-cc-pVQZ-33221 are smaller than those of the corresponding bases with the set of 33211 midbond functions. The aug-cc-pVQZ surfaces are close to the aug-cc-pV5Z, that are expected to be close to convergence. With our best surfaces the errors in the frequencies with respect to the accurate experimental results go down to 0.6%. 相似文献
49.
Facile synthesis of derivatives of 2,4-diphenyl-3-azabicyclo[3.3.1]nonane and 7,9-diphenyl-8-azabicyclo[4.3.1]decane The facile synthesis of hydantoins, cyanhydrins and aminonitriles derived from 2,4-diphenyl-3-azabicyclo[3.3.1]nonanone and 7,9-diphenyl-8-azabicyclo[4.3.1]decanone is described. Configurations at C(9) or C(10) of the new compounds wth pharmaceutical and synthetical utility is deduced from their spectral properties. 相似文献
50.
A spectrophotometric study of the chlorhexidine/bromocresol green/Triton X-100 system is reported; at pH 5.3, both 2:1 and 1:1 bromocresol green/chlorhexidine complexes are formed. In the manual spectrophotometric method, Beer's law is obeyed for chlorhexidine concentrations of 2.9–32.2 μg ml?1 (r.s.d. 0.4–1.3%); the molar absorptivity is 12 500 l mol?1 cm?1. In the flow-injection method, the calibration graph is linear for the chlorhexidine range 23.0–83.9 μg ml?1 (r.s.d. 0.8%); the injection is ca. 60 h?1. Benzocaine, acetylsalicylic acid, ascorbic acid and sucrose are tolerated at 10?2?10?3 M levels. Hibitane 5% was analyzed successfully. 相似文献