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11.
Proton Transport in a Highly Conductive Porous Zirconium‐Based Metal–Organic Framework: Molecular Insight 下载免费PDF全文
Dr. Daiane Damasceno Borges Dr. Sabine Devautour‐Vinot Dr. Hervé Jobic Dr. Jacques Ollivier Dr. Farid Nouar Dr. Rocio Semino Dr. Thomas Devic Dr. Christian Serre Prof. Francesco Paesani Prof. Guillaume Maurin 《Angewandte Chemie (International ed. in English)》2016,55(12):3919-3924
The water stable UiO‐66(Zr)‐(CO2H)2 MOF exhibits a superprotonic conductivity of 2.3×10?3 S cm?1 at 90 °C and 95 % relative humidity. Quasi‐elastic neutron scattering measurements combined with aMS‐EVB3 molecular dynamics simulations were able to probe individually the dynamics of both confined protons and water molecules and to further reveal that the proton transport is assisted by the formation of a hydrogen‐bonded water network that spans from the tetrahedral to the octahedral cages of this MOF. This is the first joint experimental/modeling study that unambiguously elucidates the proton‐conduction mechanism at the molecular level in a highly conductive MOF. 相似文献
12.
Daiane Cristina SassEmílio Carlos de Lucca Jr. Jader da Silva BarbosaKleber Thiago de Oliveira Mauricio Gomes Constantino 《Tetrahedron letters》2011,52(41):5371-5374
Conjugate reduction of ortho-substituted cinnamic esters by Stryker’s reagent to form copper enolates, followed by intramolecular aldol-type cyclization, successfully generated indane and tetralin rings in one pot efficiently. This tandem reaction is generally diastereoselective and provides good yields. 相似文献
13.
Daiane Cristina Sass Vladimir Constantino Gomes Heleno Jader da Silva Barbosa Gustavo Oliveira Morais Fernando Batista Da Costa Mauricio Gomes Constantino 《Tetrahedron letters》2013,54(7):625-627
The conversion of a germacranolide structure (tagitinin C) into a furanoheliangolide one (diversifolin) was achieved by hydride conjugate addition using Stryker’s reagent. 相似文献
14.
Ying Xiong Yan‐Zhong Fan Dr. Daiane Damasceno Borges Cheng‐Xia Chen Zhang‐Wen Wei Hai‐Ping Wang Dr. Mei Pan Dr. Ji‐Jun Jiang Prof. Guillaume Maurin Prof. Cheng‐Yong Su 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(45):16147-16156
The synthesis of stable porous materials with appropriate pore size and shape for desired applications remains challenging. In this work a combined experimental/computational approach has been undertaken to tune the stability under various conditions and the adsorption behavior of a series of MOFs by subtle control of both the nature of the metal center (Co2+, Cu2+, and Zn2+) and the pore surface by the functionalization of the organic linkers with amido and N‐oxide groups. In this context, six isoreticular MOFs based on T‐shaped ligands and paddle‐wheel units with ScD0.33 topology have been synthesized. Their stabilities have been systematically investigated along with their ability to adsorb a wide range of gases (N2, CO2, CH4, CO, H2, light hydrocarbons (C1–C4)) and vapors (alcohols and water). This study has revealed that the MOF frameworks based on Cu2+ are more stable than their Co2+ and Zn2+ analogues, and that the N‐oxide ligand endows the MOFs with a higher affinity for CO2 leading to excellent selectivity for this gas over other species. 相似文献
15.
One-step biomimetic conversion of a furanoheliangolide into an eremantholide using Stryker’s reagent
Daiane Cristina Sass Vladimir Constantino Gomes Heleno Joo Luis Callegari Lopes Mauricio Gomes Constantino 《Tetrahedron letters》2008,49(24):3877-3880
The conversion of a furanoheliangolide structure (15-deoxygoyazensolide) into an eremantholide one (eremantholide C) was achieved by tandem hydride conjugate addition–intramolecular carbanion addition using Stryker’s reagent. 相似文献
16.
de Araujo Aquino Sabrine Maciel Juliana Villela Dias Daiane 《Journal of Solid State Electrochemistry》2020,24(8):1981-1989
Journal of Solid State Electrochemistry - This work deals about the evaluation and improvement of analytical and electrochemical features of chemically modified electrode based on dihexadecyl... 相似文献
17.
Ulrich Hasse Katja Fricke Daiane Dias Gustav Sievers Harm Wulff Fritz Scholz 《Journal of Solid State Electrochemistry》2012,16(7):2383-2389
Annealed thin layers of gold with large mono-crystalline areas were treated with OH· radicals generated in an electrochemical Fenton reaction. The morphological changes observed with ex situ atomic force microscopy in non-contact mode and grazing incidence X-ray diffractometry show that the grain boundaries, and generally the non-{111} planes, are the loci of highest reactivity, i.e., the places where the gold dissolution is much faster than on the {111} planes. 相似文献
18.
Alexandre B. Schneider Paulo C. Nascimento Denise Bohrer Leandro M. de Carvalho Ananda Guarda Daiane Dias Andrea Koschinsky 《Electroanalysis》2013,25(7):1628-1634
A voltammetric method was developed for zirconium determination as Zr(IV)‐cupferron‐oxalate‐diphenylguanidine complex based on adsorptive accumulation at the HMDE (Epeak=?0.95 V). The supporting electrolyte was a mixture of acetate/acetic acid (pH 4.6) and ammonium acetate (pH 5.7) solutions. Eads=?0.6 V (vs. Ag/AgCl), tads=400 s, 10 mV s?1 scan rate, and DP mode were the main parameters. The linear range was 0.033 to 3.3×10?9 mol L?1, and the LOD and LOQ (tads=400 s) were 0.77 and 1.6×10?11 mol L?1, respectively. The method was adequate for seawater samples, although not sufficiently sensitive for surface waters. 相似文献
19.
Duarte EL Oliveira TR Alves DS Micol V Lamy MT 《Langmuir : the ACS journal of surfaces and colloids》2008,24(8):4041-4049
Barbaloin is a bioactive glycosilated 1,8-dihydroxyanthraquinone present in several exudates from plants, such as Aloe vera, which are used for cosmetic or food purposes. It has been shown that barbaloin interacts with DMPG (dimyristoylphosphatidylglycerol) model membranes, altering the bilayer structure (Alves, D. S.; Pérez-Fons, L.; Estepa, A.; Micol, V. Biochem. Pharm. 2004, 68, 549). Considering that ESR (electron spin resonance) of spin labels is one of the best techniques to monitor structural properties at the molecular level, the alterations caused by the anthraquinone barbaloin on phospholipid bilayers will be discussed here via the ESR signal of phospholipid spin probes intercalated into the membranes. In DMPG at high ionic strength (10 mM Hepes pH 7.4 + 100 mM NaCl), a system that presents a gel-fluid transition around 23 degrees C, 20 mol % barbaloin turns the gel phase more rigid, does not alter much the fluid phase packing, but makes the lipid thermal transition less sharp. However, in a low-salt DMPG dispersion (10 mM Hepes pH 7.4 + 2 mM NaCl), which presents a rather complex gel-fluid thermal transition (Lamy-Freund, M. T.; Riske, K. A. Chem. Phys. Lipids 2003, 122, 19), barbaloin strongly affects bilayer structural properties, both in the gel and fluid phases, extending the transition region to much higher temperature values. The position of barbaloin in DMPG bilayers will be discussed on the basis of ESR results, in parallel with data from sample viscosity, DSC (differential scanning calorimetry), and SAXS (small-angle X-ray scattering). 相似文献
20.
Daiane Cristina Sass 《Tetrahedron letters》2008,49(40):5770-5772
In this Letter we describe a 12% overall yield synthesis of a model for homoallylic oxygenated α-methylene-γ-butyrolactones with relative stereochemistry defined by selective hydrogenation with Rh/Al2O3. The synthesis was realized in 9 steps involving simple reactions. 相似文献