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41.
Laura Cañadillas‐Delgado Dr. Tomás Martín Dr. Oscar Fabelo Dr. Jorge Pasán Dr. Fernando S. Delgado Dr. Francesc Lloret Prof. Dr. Miguel Julve Prof. Dr. Catalina Ruiz‐Pérez Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(13):4037-4047
The preparation, X‐ray crystallography and magnetic investigation of the first examples of methanetriacetate (mta)‐containing lanthanide(III) complexes of formulae [Gd(mta)(H2O)3]n ? 4 n H2O ( 1 ) [Gd(mta)(H2O)3]n ? 2 n H2O ( 2 ) and [Gd2(mta)2(H2O)2]n ? 2 n H2O ( 3 ) are described herein. This tripodal ligand promotes the formation of 63 networks; thus 1 consists of a honeycomb structure, whereas in 2 two of these layers are condensed to form a rare five‐connected two‐dimensional (4862) network. Compound 3 can be seen as an aggregation of 63 layers leading to a three‐dimensional (6,6)‐connected binodal (41263)(4966)‐ nia net, in which the gadolinium(III) ions and the mta ligands act as octahedral and as trigonal prismatic nodes, respectively. The magnetic properties of 1 – 3 were investigated in the temperature range 1.9–300 K. A close fit to the Curie law ( 1 ) and weak either antiferro‐ [J=?0.0063(1) cm?1 ( 2 )] or ferromagnetic [J=+0.0264(6) cm?1 ( 3 )] interactions between the GdIII ions are observed; the different exchange pathways involved [extended tris‐bidentate mta ( 1 ) and μ‐O(1);κ2O(1),O(2) ( 2 and 3 ) plus single syn–syn carboxylate‐mta ( 3 )] accounting for these magnetic features. The nature and magnitude of the magnetic interactions, between the GdIII ions in 1 – 3 , agree with the small amount of data existing in the literature for these kind of bridges. 相似文献
42.
Dr. Emilio Pardo Jesús Ferrando‐Soria Dr. Marie‐Claire Dul Dr. Rodrigue Lescouëzec Dr. Yves Journaux Dr. Rafael Ruiz‐García Dr. Joan Cano Prof. Dr. Miguel Julve Prof. Dr. Francesc Lloret Dr. Laura Cañadillas‐Delgado Dr. Jorge Pasán Prof. Dr. Catalina Ruiz‐Pérez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(43):12762-12762
43.
Ferrando-Soria J Pasán J Ruiz-Pérez C Journaux Y Julve M Lloret F Cano J Pardo E 《Inorganic chemistry》2011,50(18):8694-8696
Two new heterobimetallic manganese(II)-copper(II) coordination polymers of formulas [Mn(2)Cu(2)(Me(3)mpba)(2)(H(2)O)(6)]·8H(2)O (1) and [Mn(2)Cu(2)(Me(4)ppba)(2)(H(2)O)(6)]·8H(2)O (2) [Me(3)mpba = 2,4,6-trimethyl-N,N'-1,3-phenylenebis(oxamate) and Me(4)ppba = 2,3,5,6-tetramethyl-N,N'-1,4-phenylenebis(oxamate)] have been synthesized following a molecular-programmed self-assembly method from the corresponding dicopper(II) complexes acting as metalloligands toward Mn(II) ions. 1 and 2 consist of neutral Mn(II)(2)Cu(II)(2) layers with a brick-wall structure made up of oxamato-bridged Mn(II)Cu(II) chains connected through double meta- (1) and para-substituted (2) permethylated phenylene spacers. Overall magnetic (1) and nonmagnetic (2) layer ground states result from the ferro- and antiferromagnetic interchain interactions between the oxamato-bridged Mn(II)Cu(II) ferrimagnetic chains across m- and p-phenylene spacers, respectively. Interestingly, compound 1 exhibits a long-range ferromagnetic ordering with a rather high Curie temperature (T(C)) of 20.0 K. 相似文献
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A different proof for the following result due to West is given: the Schröder number s[inn−1] equals the number of permutations on [1,2,] …, nþat avoid the pattern (3,1,4,2) and its dual (2,4,1,3). 相似文献
46.
Sigifredo Padilla Rodolfo Valdés Leonardo Gómez Déborah Geada Williams Ferro Otto Mendoza Cristina García Lorely Milá Leonardo Pasín Yordan Issac David Gavilán Tatiana González Raudel Sosa Alberto Leyva Julio Sánchez Mailín LaO Yodelis Calvo Rafael Sánchez Eutimio Fernández José Brito 《Chromatographia》2009,70(11-12):1673-1678
Transgenic plant investigations focus on fine-regulation of the recombinant protein expression and purification strategies. In this article, preliminary experiments were done at analytical-scale to decide the best plantibody HB-01 purification strategy. Once it was assumed, the purification efficiency was assessed at different scales (10–600 kg of biomass). The plantibody purity measured by SDS-PAGE and LC-GF was over 90%, yielding 9.9 ± 6.2–18.6 ± 0.9 mg plantibody kg?1 of biomass and 39.9 ± 7.9–48.7 ± 2.1% of recovery. Significant differences were not observed among these parameters at these scales. Plant DNA contents were <3.3 ng mg?1 of plantibody, which is considered very low for the plantibody HB-01 application in the hepatitis B vaccine production. 相似文献
47.
A. Aguirrechu-Comerón J. Pasán J. González-Platas J. Ferrando-Soria R. Hernández-Molina 《Journal of Structural Chemistry》2015,56(8):1563-1571
The preparation of four new copper(II) complexes with different N-donor ligands [CuBr2(2-benzylpyridine)2] (1), [CuBr2(2-benzylpyridine)(2,2′-bipyridine)]·H2O (2), [CuBr2(3-methyl-2-phenylpiridine)2] (3), [Cu(picolinate)2]·KI (4) from copper(I) halides as starting material is described. During the preparation of compound 4 a ligand oxidation reaction took place to give the picolinate ligand starting from 2-(2-methylaminoethyl)pyridine. The complexes were characterized by elemental analyses, IR spectroscopy and crystallographic studies. Single crystal X-ray diffraction analysis of the complexes reveals their monomeric penta- and tetracoordinated nature. For all compounds, the copper(II) present a common square planar coordination except for compound 2 which is five coordinated in a quasi-square pyramidal configuration with τ of 0.29. The Cu–N distances for these compounds are in the range of 1.959(4)-2.041(3) Å, Cu–O distance was 1.961(3) Å and Cu–Br distances were in the range of 2.4052(4)-2.4381(6) Å for the square base configuration while for apical distance it was 2.6745(7) Å. Magnetic properties have been investigated for all compounds in the temperature range 2-300 K. Compound 1 shows weak antiferromagnetic intermolecular interaction. 相似文献
48.
Pardo E Ferrando-Soria J Dul MC Lescouëzec R Journaux Y Ruiz-García R Cano J Julve M Lloret F Cañadillas-Delgado L Pasán J Ruiz-Pérez C 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(43):12838-12851
Double‐stranded copper(II) string complexes of varying nuclearity, from di‐ to tetranuclear species, have been prepared by the CuII‐mediated self‐assembly of a novel family of linear homo‐ and heteropolytopic ligands that contain two outer oxamato and either zero ( 1 b ), one ( 2 b ), or two ( 3 b ) inner oxamidato donor groups separated by rigid 2‐methyl‐1,3‐phenylene spacers. The X‐ray crystal structures of these CuIIn complexes (n=2 ( 1 d ), 3 ( 2 d ), and 4 ( 3 d )) show a linear array of metal atoms with an overall twisted coordination geometry for both the outer CuN2O2 and inner CuN4 chromophores. Two such nonplanar all‐syn bridging ligands 1 b – 3 b in an anti arrangement clamp around the metal centers with alternating M and P helical chiralities to afford an overall double meso‐helicate‐type architecture for 1 d – 3 d . Variable‐temperature (2.0–300 K) magnetic susceptibility and variable‐field (0–5.0 T) magnetization measurements for 1 d – 3 d show the occurrence of S=nSCu (n=2–4) high‐spin ground states that arise from the moderate ferromagnetic coupling between the unpaired electrons of the linearly disposed CuII ions (SCu=1/2) through the two anti m‐phenylenediamidate‐type bridges (J values in the range of +15.0 to 16.8 cm?1). Density functional theory (DFT) calculations for 1 d – 3 d evidence a sign alternation of the spin density in the meta‐substituted phenylene spacers in agreement with a spin polarization exchange mechanism along the linear metal array with overall intermetallic distances between terminal metal centers in the range of 0.7–2.2 nm. Cyclic voltammetry (CV) and rotating‐disk electrode (RDE) electrochemical measurements for 1 d – 3 d show several reversible or quasireversible one‐ or two‐electron steps that involve the consecutive metal‐centered oxidation of the inner and outer CuII ions (SCu=1/2) to diamagnetic CuIII ones (SCu=0) at relatively low formal potentials (E values in the range of +0.14 to 0.25 V and of +0.43 to 0.67 V vs. SCE, respectively). Further developments may be envisaged for this family of oligo‐m‐phenyleneoxalamide copper(II) double mesocates as electroswitchable ferromagnetic ‘metal–organic wires’ (MOWs) on the basis of their unique ferromagnetic and multicenter redox behaviors. 相似文献
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Pardo E Bernot K Julve M Lloret F Cano J Ruiz-García R Pasán J Ruiz-Pérez C Ottenwaelder X Journaux Y 《Chemical communications (Cambridge, England)》2004,(8):920-921
An octanuclear copper(II) complex possessing a dimer-of-tetramers structure self-assembles from a binuclear oxamatocopper(II) metallacryptand of the meso-helicate type; its magnetic behaviour is consistent with its unique double-propeller molecular topology. 相似文献
50.
Sacconi L Romano G Ballerini R Capitanio M De Pas M Giuntini M Dunlap D Finzi L Pavone FS 《Optics letters》2001,26(17):1359-1361
A magneto-optic trap for micro-objects is described. Magnetic beads were trapped by optical tweezers while being rotated by a new integrated magnetic manipulator. Rotation was achieved with eight electromagnets with tip-pole geometry. The time orbital potential technique was used to achieve rotation of magnetic beads. Trapping in three dimensions and rotation of magnetic beads on three axes are demonstrated with forces up to 230 pN and force momenta of up to 10(-16)N m . A position-detection apparatus based on an interferometric scheme provides nanometer sensitivities in a few milliseconds. 相似文献