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981.
García-Gallego S Rodríguez JS Jiménez JL Cangiotti M Ottaviani MF Muñoz-Fernández MÁ Gómez R de la Mata FJ 《Dalton transactions (Cambridge, England : 2003)》2012,41(21):6488-6499
We describe here the synthesis and characterization of new sulfonated and carboxylated-containing N-donor ligands [Na(4)(edts)]·4H(2)O (2), [Na(2)(dmeddp)]·2H(2)O (3) and [Na(4)(edtp)]·H(2)O (4) (edts = ethylene-diamine- N,N,N',N'-tetraethylenesulfonate ion; dmeddp = dimethyl-ethylene-diamine-N,N,N',N'-tetra-3-propionate ion; edtp = ethylene-diamine-N,N,N',N'-tetra-3-propionate ion) and their corresponding metal (Ni, Co, Cu and Zn) complexes. Mainly, UV-Vis and a computer aided analysis of the EPR spectra provided information on the geometry and structure of the complexes in solution. Some of the metal complexes inhibit HIV replication when treating both pre- and post-infected PBMC cells, and hustle the inhibitory effect compared to the metal salts alone. 相似文献
982.
983.
Aurelio Heredia Roberto Ambrosio Mario Moreno Carlos Zuñiga Abimael Jiménez Karim Monfil Javier de la Hidalga 《Journal of Non》2012,358(17):2331-2335
In this work is presented the fabrication of a thin film membrane as a bio-transducer for aural assistance detection, therefore it will operate at low pressure. The resonant membrane was deposited by PECVD technique at low temperature of deposition T = 270 °C, using SiH4, GeH4, and Boron gases. The membrane was suspended on a micromachined crystalline silicon frame obtained by wet chemical etching. The a-SiGe:B film presented a resistivity of 2.46 × 103 (Ω-cm), resistance of 20.8 kΩ. Using these experimental data we succeeded in designing a simple structure for sensing low pressure variations. The output voltage of the sensor was measured for a range of pressure from 0 to 3000 Pa and at bias voltage of 10 V. 相似文献
984.
Salim Elzwawi Hyung Suk Kim Robert Heinhold Max Lynam Gary Turner Jim G. Partridge Dougal G. McCulloch Roger J. Reeves Martin W. Allen 《Physica B: Condensed Matter》2012,407(15):2903-2906
In this paper we report on the structural, electrical and optical characteristics of unintentionally doped ZnO films grown on a-plane sapphire substrates using the Filtered Cathodic Vacuum Arc (FCVA) technique. The resulting films showed considerable promise for device applications with properties including high transparency, moderate intrinsic carrier concentrations (1017–1019 cm−3), electron mobilities up to 30 cm2/Vs, low surface roughness (typically <2% of film thickness) and well-structured photoluminescence. Post-annealing in oxygen at temperatures up to 800 °C produced significant improvements in the properties of these films. Silver oxide Schottky diodes fabricated on FCVA ZnO showed ideality factors as low as 1.20 and good sensitivity to ultraviolet light. 相似文献
985.
Field JJ Pera B Calvo E Canales A Zurwerra D Trigili C Rodríguez-Salarichs J Matesanz R Kanakkanthara A Wakefield SJ Singh AJ Jiménez-Barbero J Northcote P Miller JH López JA Hamel E Barasoain I Altmann KH Díaz JF 《Chemistry & biology》2012,19(6):686-698
Zampanolide and its less active analog dactylolide compete with paclitaxel for binding to microtubules and represent a new class of microtubule-stabilizing agent (MSA). Mass spectrometry demonstrated that the mechanism of action of both compounds involved covalent binding to β-tubulin at residues N228 and H229 in the taxane site of the microtubule. Alkylation of N228 and H229 was also detected in α,β-tubulin dimers. However, unlike cyclostreptin, the other known MSA that alkylates β-tubulin, zampanolide was a strong MSA. Modeling the structure of the adducts, using the NMR-derived dactylolide conformation, indicated that the stabilizing activity of zampanolide is likely due to interactions with the M-loop. Our results strongly support the existence of the luminal taxane site of microtubules in tubulin dimers and suggest that microtubule nucleation induction by MSAs may proceed through an allosteric mechanism. 相似文献
986.
Ceacero-Vega AA Ballesteros B Bejan I Barnes I Jiménez E Albaladejo J 《The journal of physical chemistry. A》2012,116(16):4097-4107
Relative kinetic techniques have been used to measure the rate coefficients for the reactions of oxygenated terpenes (menthol, borneol, fenchol, camphor, and fenchone) and cyclohexanol with hydroxyl radicals (OH) and chlorine atoms (Cl) at 298 ± 2 K and atmospheric pressure. The rate coefficients obtained for the reactions of the title compounds with OH are the following (in units of 10(-11) cm(3) molecule(-1) s(-1)): (1.48 ± 0.31), (2.65 ± 0.32), (2.49 ± 0.30), (0.38 ± 0.08), (0.39 ± 0.09) for menthol, borneol, fenchol, camphor, and fenchone, respectively. For the corresponding reactions with Cl atoms the rate coefficients are as follows (in units of 10(-10) cm(3) molecule(-1) s(-1)): (3.21 ± 0.26), (3.40 ± 0.28), (2.72 ± 0.13), (2.93 ± 0.17), (1.59 ± 0.10), and (1.86 ± 0.29) for cyclohexanol, menthol, borneol, fenchol, camphor, and fenchone, respectively. The reported error is twice the standard deviation. Product studies of the reactions were performed using multipass in situ FTIR (Fourier transform infrared spectroscopy) and solid-phase microextraction (SPME) with analysis by GC-MS (gas chromatography-mass spectrometry). A detailed mechanism is proposed to justify the observed reaction products. 相似文献
987.
Blanca M. Mu?oz-Flores Víctor M. Jiménez-Pérez Rosa Santillan Eugenio Hernández-Fernández Susana López-Cortina Boris I. Kharisov 《Journal of chemical crystallography》2012,42(1):34-37
Abstract
Reaction of the β-diketiminato lithium salt {CH[(CtBu)(2,6-iPr2C6H3N)]2}−Li+ with SnCl2 provided the derivative {CH[(CtBu)(2,6-iPr2C6H3N)2}SnCl with a three-coordinate tin(II) ion. The crystal structure shows a non-planar ligand skeleton and a tin(II) ion with a distorted tetrahedral pyramidal geometry with one vertex occupied by an unshared electron pair. The Sn(II) ion out of the N2–C3–C2–C1–N1 plane (Φ-length) is 0.674 ? because of the steric hindrance between the tert-butyl groups and the N-aryl groups. The Sn–N1 [2.224 (19) ?] and Sn–N2 [2.1423 (18) ?] distances in the heterocycle corresponded with a delocalized system, while the most acute angle was associated with the bite of the chelating ligand N–Sn–N 87.94 (7)°. 相似文献988.
M. Hernández-Escolano X. Ramis A. Jiménez-Morales M. Juan-Díaz J. Suay 《Journal of Thermal Analysis and Calorimetry》2012,107(2):499-508
A set of materials has been prepared by sol–gel process containing different quantities of hydroxyapatite (0, 2.5 and 5% HAp
w/w) using as silica precursors glycidyloxypropyltrimethoxysilane (GPTMS) and triethoxyvinylsilane (VTES). In order to optimize
the curing process to obtain sintherized systems (inorganic network) or hybrid systems (organic–inorganic) a TG and FTIR studies
have been developed and degradation kinetic triplet parameters were obtained (the activation energy, pre-exponential factor,
and function of degree of conversion). The kinetic study was analyzed by means of an integral isoconversional non-isothermal
procedure (model free), and the kinetic model was determined by the Coats–Redfern method and through the compensation effect
(IKR). All the systems followed the n = 6 kinetic model. The addition of HAp increases the thermal stability of the systems. The isothermal degradation was simulated
from non-isothermal data, and the curing process could be defined to obtain the two types of materials. Temperature under
250 °C allows the formation of hybrids networks. 相似文献
989.
Salinas-Sánchez DO Herrera-Ruiz M Pérez S Jiménez-Ferrer E Zamilpa A 《Molecules (Basel, Switzerland)》2012,17(4):4292-4299
The aim of this study was to identify an anti-inflammatory compound from D. viscosa leaves. The structure of this bioactive substance was elucidated by IR and NMR studies, which indicated that this natural product corresponds to hautriwaic acid (HA). This diterpene exhibited good anti-inflammatory activity in 12-O-tetradecanoylphorbol 13-acetate (TPA) mice ear edema models by applications at doses of 0.25, 0.5 and 1.0 mg/ear (60.2, 70.2 and 87.1% inhibition, respectively); additionally Dodonaea viscosa dichloro-methane extract (DvDE) displays a 97.8% anti-inflammatory effect at 3 mg/kg. Multiple applications of DvDE at doses of 100 mg/kg on TPA mice ear edema inhibited the edema-associated inflammation by 71.8%, while HA at doses of 15 mg/kg, reduced edema to 64% and indomethacin 40%. 相似文献
990.