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991.
992.
González-Veloso Iván Rodríguez-Otero Jesús Cabaleiro-Lago Enrique M. 《Structural chemistry》2019,30(3):647-656
Structural Chemistry - Using dispersion-corrected DFT methods, an exhaustive computational study of all possible complexes between the carbon nanorings, CNRs, [10]CPP and [6]CPPA with the... 相似文献
993.
Stochastic Stability of Lyapunov Exponents and Oseledets Splittings for Semi‐invertible Matrix Cocycles
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We establish (i) stability of Lyapunov exponents and (ii) convergence in probability of Oseledets spaces for semi‐invertible matrix cocycles subjected to small random perturbations. The first part extends results of Ledrappier and Young to the semi‐invertible setting. The second part relies on the study of evolution of subspaces in the Grassmannian; the analysis developed here is based on higher‐dimensional Möbius transformations and is likely to be of wider interest. © 2015 Wiley Periodicals, Inc. 相似文献
994.
Kieran Griffiths Dr. Christopher W. D. Gallop Dr. Alaa Abdul‐Sada Dr. Alfredo Vargas Dr. Oscar Navarro Dr. George E. Kostakis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6358-6361
Three isoskeletal tetranuclear coordination clusters with general formula [MII2DyIII2L4(EtOH)6](ClO4)2?2 EtOH, (M=Co, 1 ; M=Ni, 2 ) and [NiII2DyIII2L4Cl2(CH3CN)2]?2 CH3CN ( 3 ), have been synthesized and characterized. These air‐stable compounds, and in particular 3 , display efficient homogeneous catalytic behavior in the room‐temperature synthesis of trans‐4,5‐diaminocyclopent‐2‐enones from 2‐furaldehyde and primary or secondary amines under a non‐inert atmosphere. 相似文献
995.
Back Cover: Multipurpose Nature of Rapid Covalent Functionalization on Carbon Nanotubes (Chem. Eur. J. 51/2015)
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996.
Cover Picture: Platinum trans‐Bis(borirene) Complexes Displaying Coplanarity and Communication Across a Platinum Metal Center (Chem. Eur. J. 6/2015)
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997.
Jose Luis Gómez-Ariza Alfredo Velasco-arjona Inmaculada Giráldez Daniel Sánchez-Rodas Emilio Morales 《International journal of environmental analytical chemistry》2013,93(3-4):427-440
Abstract A method for speciation of dimethylselenide (DMeSe), dimethyldiselenide (DMeDSe) and diethylselenide (DEtSe) in sediments based on a coupling between a pervaporation module, a preconcentration sorptive trap and a gas chromatograph-mass spectrometer is reported. The coupling is performed through a high pressure injection valve which allows two different operational modes: (a) analysis without preconcentration, in which analytes are directly driven from the pervaporation chamber to the injection port of the chromatograph, and (b) analysis with preconcentration in a trap, in which the analytes from the pervaporation chamber are first trapped on a Tenax minicolumn and then thermally desorbed and driven to the GC. This second approach improves the sensitivity compared to the direct coupling, reaching estimated absolute detection limits lower than 0.6 ng Se for each tested species. The method is applied to the determination of volatile organic selenium species in several sediments collected from different areas in the Southwest of Spain. 相似文献
998.
Vianney Aguilar-Vargas Jaime S. Valente Ignacio González 《Journal of Solid State Electrochemistry》2013,17(12):3145-3152
Two hydrotalcite-like compounds (HTs) were synthesized by coprecipitation. The electrochemical behavior of MgZnGa ([Mg0.58 Zn0.17Ga0.25 (OH)2] (CO3)2? 0.125 1.5 H2O) and ZnGaAl ([Zn0.75Ga0.19 Al0.06 (OH)2] (CO3)2? 0.125·1.5 H2O) Hydrotalcite-like compounds (HTs) was studied in NaOH at different concentrations. Voltammetric and chronoamperometric studies were performed to identify oxidation and reduction processes and the effect of the cations in total reactivity. Electrocatalytic effect of HTs on hydroxide electrochemical oxidation shows better performance of MgZnGa; this is apparently due to the presence of Mg and a greater amount of Ga3+ in the lattice of this HT. As far as reduction is concerned, Zn(II) reduction process is observed within the lattices of both HTs and is influenced by both the amount of OH? in the solution and the potential which the previous oxidation has been performed. 相似文献
999.
F. J. González-Vila T. Verdejo F. Martin 《International journal of environmental analytical chemistry》2013,93(1-3):213-222
Abstract The lipidic fraction compositions of both concentrated vinasses, a by-product of the sugar industry, and a compost made basically from olive oil vegetation waters (alpechin) were studied. The alpechin lipids are composed mainly by series of n-alkanes and lineal and branched fatty acids, whereas the major lipids in vinasses were n-alkanes, n-alkanols and acetals. Concentrations and composition of lipids in both materials do not seem of concern. Preliminary results on the effects of the application of both materials over two years on the organic status of an agricultural soil are also reported. No significant changes were observed in total organic carbon and contents in humic fractions and lipids before and after the applications. However, analysis by GC-MS of the lipid compounds present in bound forms in the subsoil layer revealed that some hydrophobic components were accumulated in the soil following the waste applications. 相似文献
1000.