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91.
Ferreira-Aparicio P Rodríguez-Ramos I Guerrero-Ruiz A 《Chemical communications (Cambridge, England)》2002,(18):2082-2083
A high efficiency membrane reactor (Pd based) has been developed for hydrogen generation from methylcyclohexane, which is able to produce a pure hydrogen stream with a reaction yield close to 100%. 相似文献
92.
93.
Paloma Ovejero Mercedes Cano José A. Campo Elena Pinilla M. Rosario Torres 《Journal of organometallic chemistry》2007,692(19):4093-4105
Three new ionic silver complexes based on the 3,5-dimethyl-4-nitropyrazole ligand (HpzNO2) and 1:2 or 1:3 (Ag:HpzNO2) stoichiometries, [Ag(HpzNO2)2][BF4], [Ag(HpzNO2)3][SbF6] and [Ag(HpzNO2)3][PO2F2]·HpzNO2 have been prepared and structurally characterised. The linear or trigonal metallic coordination environment, the NO2 groups on the pyrazole ligand as well as the presence of counteranions of the type as , or (the latter one evolving to ) were strategically selected to produce molecular assemblies established on the basis of hydrogen-bonds (N-H?X) and π?π or coordinative interactions involving the NO2 group. The complex [Ag(HpzNO2)2][BF4] exhibited polymeric N-H?F hydrogen-bonded chains which were assembled in a 3D network by weaker coordinative Ag?O(NO2) and π(NO2)?π(NO2) interactions. In the complex [Ag(HpzNO2)3][SbF6], consistent with the three-coordinated molecular environment, the interactions were extended to give rise an open 3D cationic sub-network in which the counteranions were encapsulated. By contrast, in the related complex [Ag(HpzNO2)3][PO2F2]·HpzNO2 the presence of a fourth non-coordinated pyrazole HpzNO2 avoided the formation of a 3D network giving rise to a double-chained 1D structure. 相似文献
94.
Paloma Ovejero Mercedes Cano María Cristina Lagunas 《Journal of organometallic chemistry》2007,692(8):1690-1697
A series of pyrazole (Hpz) and pyrazolate (pz−) Au(I) complexes of types [Au(Hpz2R(n))(PPh3)]+ (I), [Au(Hpz2R(n))2]+ (II), [Au(μ-pzR(n))]3 (III), [Au(pzR(n)/2R(n))(PPh3)] (IV), [AuCl(HpzR(n)/2R(n))] (V) and [(PPh3)Au(μ-pzR(n))Au(PPh3)]+ (VI), R(n) and 2R(n) represent C6H4OCnH2n+1 substituents at the 3- or 3- and 5-positions of the heterocyclic ring, respectively, have been shown to be luminescent in the solid state at 77 K, independently of the presence or not of inter-metallic Au-Au interactions. The emission spectra of all complexes consist of structured bands in the region 395-500 nm, attributed to ligand-to-metal charge transfer (LMCT) transitions involving the Hpz or pz− ligands, the pattern of bands of compounds being related with the molecular structure and/or the nature of the ligands. The thermal behaviour of several complexes of the types III, IV and V containing long-chain substituents (n ? 12) was examined by polarising light optical microscopy (POM). The derivative [AuCl(HpzR(12))] was proved to have liquid crystal properties exhibiting a mesophase SmA but the remaining complexes were not liquid crystal materials. This complex is one of the scarce examples of Au(I) derivatives exhibiting both liquid crystal and luminescent properties. 相似文献
95.
Mas S Touboul D Brunelle A Aragoncillo P Egido J Laprévote O Vivanco F 《The Analyst》2007,132(1):24-26
Several frozen vessels bearing atherosclerotic lesion were analysed by cluster TOF-SIMS (time-of-flight secondary ion mass spectrometry) to map their lipid (fatty acids, cholesterol, vitamin E, phosphatidic acids, phosphatidylinositols and triglycerides) content at a micrometric resolution. 相似文献
96.
Paloma Lozano-Picazo Cristina Castro-Domínguez Augusto Luis Bruno Alejandro Baeza Adelia S. Martínez Patricia A. Lpez ngela Castro Yassmin Lakhal Elena Montero Luis Colchero Daniel Gonzlez-Nieto Francisco Javier Rojo Fivos Panetsos Milagros Ramos Rafael Daza Alfonso M. Gan-Calvo Manuel Elices Gustavo Víctor Guinea Jos Prez-Rigueiro 《Molecules (Basel, Switzerland)》2022,27(13)
High-performance regenerated silkworm (Bombyx mori) silk fibers can be produced efficiently through the straining flow spinning (SFS) technique. In addition to an enhanced biocompatibility that results from the removal of contaminants during the processing of the material, regenerated silk fibers may be functionalized conveniently by using a range of different strategies. In this work, the possibility of implementing various functionalization techniques is explored, including the production of fluorescent fibers that may be tracked when implanted, the combination of the fibers with enzymes to yield fibers with catalytic properties, and the functionalization of the fibers with cell-adhesion motifs to modulate the adherence of different cell lineages to the material. When considered globally, all these techniques are a strong indication not only of the high versatility offered by the functionalization of regenerated fibers in terms of the different chemistries that can be employed, but also on the wide range of applications that can be covered with these functionalized fibers. 相似文献
97.
Yáñez-Sedeño Paloma Pedrero María Campuzano Susana Pingarrón José M. 《Journal of Solid State Electrochemistry》2021,25(1):3-13
Journal of Solid State Electrochemistry - Due to their widespread use in veterinary medicine, the presence of tetracyclines (TCs) and their metabolites in foodstuffs from treated animal represents... 相似文献
98.
Ernesto Sanz Antonio Saa-Requejo Carlos H. Díaz-Ambrona Margarita Ruiz-Ramos Alfredo Rodríguez Eva Iglesias Paloma Esteve Brbara Soriano Ana M. Tarquis 《Entropy (Basel, Switzerland)》2021,23(5)
Estimates suggest that more than 70% of the world’s rangelands are degraded. The Normalized Difference Vegetation Index (NDVI) is commonly used by ecologists and agriculturalists to monitor vegetation and contribute to more sustainable rangeland management. This paper aims to explore the scaling character of NDVI and NDVI anomaly (NDVIa) time series by applying three fractal analyses: generalized structure function (GSF), multifractal detrended fluctuation analysis (MF-DFA), and Hurst index (HI). The study was conducted in four study areas in Southeastern Spain. Results suggest a multifractal character influenced by different land uses and spatial diversity. MF-DFA indicated an antipersistent character in study areas, while GSF and HI results indicated a persistent character. Different behaviors of generalized Hurst and scaling exponents were found between herbaceous and tree dominated areas. MF-DFA and surrogate and shuffle series allow us to study multifractal sources, reflecting the importance of long-range correlations in these areas. Two types of long-range correlation appear to be in place due to short-term memory reflecting seasonality and longer-term memory based on a time scale of a year or longer. The comparison of these series also provides us with a differentiating profile to distinguish among our four study areas that can improve land use and risk management in arid rangelands. 相似文献
99.
Paloma Merello Elena de la Poza Lucas Jódar 《Mathematical Methods in the Applied Sciences》2020,43(14):8089-8104
In recent decades, pathological consumption has become a growing behavioral misbehavior. Impulsive consumption is governed by two internal behavioral mechanisms that respond fundamentally to the hedonism or Pascal effect and to the emulation or Veblen effect. Today's development of technology acts as a catalyst of consumption by increasing access and availability to products, as well as the advertisement impact. This paper presents a compartmental discrete matrix mathematical model that allows short-term estimates of ordinary, impulsive, and pathological buyers in Spain in three different economic scenarios. The results show that impulsive and pathological buyers will increase in all the economic scenarios. Notable differences in the number of ordinary buyers are found for the group aged over 65 years. 相似文献
100.
María Moreno‐Guzmán Araceli González‐Cortés Paloma Yáñez‐Sedeño José M. Pingarrón 《Electroanalysis》2012,24(5):1100-1108
A novel dual electrochemical immunosensor for the multiplexed determination of adrenocorticotropin (ACTH) and cortisol is reported. Aminophenylboronic acid‐modified dual screen‐printed carbon electrodes were prepared on which the corresponding ACTH and cortisol antibodies were immobilized. Competitive immunoassays involved biotinylated ACTH and alkaline phosphatase labelled streptavidin, or alkaline phosphatase labelled cortisol. Differential pulse voltammetry upon 1‐naphtyl phosphate addition was employed to monitor the affinity reactions. The ranges of linearity were 5.0×10?5?0.1 and 0.1?500 ng/mL for ACTH and cortisol. The usefulness of the dual immunosensor was demonstrated by analyzing certified human serum samples with good recoveries. 相似文献