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101.
Cinabro D Henderson S Kinoshita K Liu T Saulnier M Wilson R Yamamoto H Sadoff AJ Ammar R Ball S Baringer P Coppage D Copty N Davis R Hancock N Kelly M Kwak N Lam H Kubota Y Lattery M Nelson JK Patton S Perticone D Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Nemati B O'Neill JJ Romero V Severini H Sun CR Zoeller MM Crawford G Fulton R Fujino D Gan KK Kagan H Kass R Lee J Malchow R Morrow F Skovpen Y Sung M White C Whitmore J Wilson P Butler F Fu X Kalbfleisch G Lambrecht M Ross WR 《Physical review letters》1993,70(24):3700-3704
102.
Thomas Andre´s Wolcan Ezequiel Fe´liz Mario R. Capparelli Alberto L. 《Transition Metal Chemistry》1997,22(6):541-544
The kinetics of the complexation of NiII by pteroylglutamic acid have been studied in the 545 ∘C range, the ionic strength
(0.6 M) being regulated with KNO3, in the 5.5–7.0pH range, using the stopped-flow method. Under the experimental conditions
two processes were observed. The faster process was detected in the millisecond range and is associated with the reaction
between NiII and the ligand. The slower is observed within a few seconds. Complementary equilibrium studies were made at 25
∘C. The results are consistent with the formation of a 1:1 complex between the reactants, and a mechanism is proposed to account
for the observed behaviour. Equilibrium constants for the NiII plus pteroylglutamic acid system, as well as activation parameters,
are reported.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
103.
J. Sanmartín M. R. Bermejo J. A. García-Vázquez J. Romero A. Sousa J. Strähle A. Brodbeck 《Transition Metal Chemistry》1993,18(2):187-190
Summary The electrochemical oxidation of anodic metal (nickel or cobalt) in MeCN solutions of 1-hydroxy-2-pyridinethione (HPT) gives [Ni(PT)2], [Co(PT)2] or [Co(PT)3]. When 1,10-phenanthroline (phen) or 2,2-bipyridine (bipy) are added to the electrolytic phase the product is a complex, [Ni(PT)2L] or [Co(PT)2L] (L = bipy or phen). The i.r., u.v. and 1H- and 13C-n.m.r. spectra of the complexes are discussed.This paper was presented at the 5th Inorganic Chemistry Meeting of the Royal Spanish Chemical Society, Tossa de Mar, Girona, Spain, September 1991. 相似文献
104.
New Hg2+ and Cu2+ selective chromo- and fluoroionophore based on a bichromophoric azine 总被引:1,自引:0,他引:1
[graph: see text] A new probe, 1,4-bis(1-pyrenyl)-2,3-diaza-1,3-butadiene, selectively senses Hg2+ and Cu2+ through two different channels: the yellow-deep-pink color change and the enhancement of the fluorescence with the red shift of the excimer emission, which can visually be discernible by a green fluorescence in the presence of Hg2+ and an orange fluorescence in the presence of Cu2+. 相似文献
105.
Lorenzo Testaferri Marcello Tiecco Marco Tingoli Donatella Bartoli Alberto Massoli 《Tetrahedron》1985,41(7):1373-1384
The reactions of 2,6- and 2,5-dibromopyridines and of 2,3- and 3,5-dichloropyridines with sodium isopropanethiolate and methanethiolate afforded the products of mono- or of bis-substitution depending on the experimental conditions. The same pyridines reacted with sodium methoxide to give good yields of the mono-substituted products; bis-substitution occurred easily only in the case of the 2,6-dibromo- and of the 3,5-dichloropyridine. The syntheses of some methoxy thiomethoxypyridine, starting from the halogeno methoxypyridines or from the halogeno thiomethoxypyhdines are also described. The bis-(alkylthio)pyridines can be fragmented by sodium in HMPA to give the bis(mercapto)pyridines. 相似文献
106.
Fiammengo R Wojciechowski K Crego-Calama M Timmerman P Figoli A Wessling M Reinhoudt DN 《Organic letters》2003,5(19):3367-3370
[structure: see text] Water-soluble models of heme-protein active sites are obtained via the self-assembly of cationic porphyrins 1 and tetrasulfonato calix[4]arene 2 (K(1.2)() = 10(5) M(-)(1)). Selective binding of ligands either outside or inside the cavity of assemblies 1.2 via coordination to the zinc center has been observed. Small ligands such as 4-methylpyridine and 1-methylimidazole are encapsulated, while the bulkier caffeine is bound outside. Assemblies Co-1.2, in which the Zn porphyrin moiety has been replaced by a Co(II) porphyrin, can act as O(2) carriers. 相似文献
107.
The fluorimetric determination of adrenaline is carried out in a continuous-flow assembly and by means of the molecular dissolved oxygen. The sample solution merges with an NaOH stream, then the resulting mixture is heated at 73 °C and led to the flow-cell of the fluorimeter. The flow-assembly is very simple and the procedure is quick (107 samples h–1) reproducible (R.S.D. 0.6%), selective and suitable to be applied to determination of adrenaline in formulations. Calibrations graph are linear over the ranges 0.05–15 and 20–40 mgl–1. 相似文献
108.
We introduce a new Monte Carlo algorithm for the self-avoiding walk (SAW), and show that it is particularly efficient in the critical region (long chains). We also introduce new and more efficient statistical techniques. We employ these methods to extract numerical estimates for the critical parameters of the SAW on the square lattice. We find=2.63820 ± 0.00004 ± 0.00030=1.352 ± 0.006 ± 0.025v=0.7590 ± 0.0062 ± 0.0042 where the first error bar represents systematic error due to corrections to scaling (subjective 95% confidence limits) and the second bar represents statistical error (classical 95% confidence limits). These results are based on SAWs of average length 166, using 340 hours CPU time on a CDC Cyber 170–730. We compare our results to previous work and indicate some directions for future research. 相似文献
109.
The interpretation of the infrared active fundamentals of TCNQ and chloranil monovalent anions is given for the first time. The rationalization of the infrared spectra was made possible by the recently achieved vibrational assignment of the corresponding neutral molecules and is mainly based on a set of judicious adjustments of their empirical valence force fields. 相似文献
110.
A novel alkaloid with an unprecedented ring system consisting of a dodecahydro-7-oxa-9a-aza-benzo[a]azulene ring (1), has been isolated from cultures of Clitocybe concava (Basidiomycetae). Its structure and relative stereochemistry were elucidated on the basis of spectroscopic data. Concavine presents a weak antibacterial activity. 相似文献