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101.
Improved CO2 Capture from Flue Gas by Basic Sites,Charge Gradients,and Missing Linker Defects on Nickel Face Cubic Centered MOFs 下载免费PDF全文
Elena López‐Maya Carmen Montoro Valentina Colombo Elisa Barea Jorge A. R. Navarro 《Advanced functional materials》2014,24(39):6130-6135
The adsorptive properties of the isoreticular series [Ni8(OH)4(H2O)2(BDP_X)6] (H2BDP_X = 1,4‐bis(pyrazol‐4‐yl)benzene‐4‐X with X = H (1), OH (2), NH2 (3)) can be enhanced by postsynthetic treatment with an excess of KOH in ethanol. In the case of X = H, NH2, this treatment leads to partial removal of the organic linkers, deprotonation of coordinated water molecules and introduction of extraframework cations, giving rise to materials of K[Ni8(OH)5(EtO)‐(H2O)2(BDP_X)5.5] (1@KOH, 3@KOH) formulation, in which the original framework topology is maintained. By contrast, the same treatment with KOH in the [Ni8(OH)4(H2O)2(BDP_OH)6] (2) system, enclosing the more acidic phenol residues, leads to a new material containing a larger fraction of missing linker defects and extra‐framework cations as well as phenolate residues, giving rise to the material K3[Ni8(OH)3(EtO)(H2O)6(BDP_O)5] (2@KOH), which also conserves the original face cubic centered (fcu) topology. It is noteworthy that the introduction of missing linker defects leads to a higher accessible pore volume with a concomitant increased adsorption capacity. Moreover, the creation of coordinatively unsaturated metal centers, charge gradients, and phenolate nucleophilic sites in 2@KOH gives rise to a boosting of CO2 capture features with increased adsorption heat and adsorption capacity, as proven by the measurement of pulse gas chromatography and breakthrough curve measurements of simulated flue gas. 相似文献
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Michael Ortiz Bahram Nour-Omid Elisa D. Sotelino 《International journal for numerical methods in engineering》1988,26(2):379-391
The accuracy of a new class of concurrent, procedures for transient finite element analysis is examined. A phase error analysis is carried out which shows that wave retardation leading to unacceptable loss of accuracy may occur if a Courant condition based on the dimensions of the subdomains is violated. Numerical tests suggest that this Courant condition is conservative for typical structural applications and may lead to a marked increase in accuracy as the number of subdomains is increased. Theoretical speed-up ratios are derived which suggest that the algorithms under consideration can be expected to exhibit a performance superior to that of globally implicit methods when implemented on parallel machines. 相似文献
105.
Long Nicholas; Slater Elisa; Forehand Rex; Fauber Robert 《Canadian Metallurgical Quarterly》1988,56(3):467
Three groups of young adolescent subjects were compared on several measures of adjustment in the school setting. The three groups of subjects included (a) a group from recently divorced families in which high levels of interparental conflict prior to parental separation and after the divorce had been reported, (b) a group from recently divorced families in which high levels of interparental conflict prior to parental separation but low levels after the divorce had been reported, and (c) a comparison group from intact families. Adolescents from the first group were found to be functioning at a lower level than those from the other two groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
A new and efficient protocol to prepare 2-(R-anilino)-1,4-naphthoquinones in quantitative yields is presented. This synthesis occurs under mild conditions by reacting the corresponding aniline and 1,4-naphthoquinone in the presence of a bentonitic clay. The role of the clay is explained in terms of a reaction mechanism in which an activated complex is formed by the reaction of 1,4-naphthoquinone with Lewis acid sites of the clay. Based on the chemical composition of the clay, with Fe3+ sites, the last step of the mechanism is proposed to involve an oxidation-reduction reaction. 相似文献
107.
Elisa?BertinoEmail author Igor?Nai?Fovino Loredana?Parasiliti?Provenza 《Data mining and knowledge discovery》2005,11(2):121-154
Recently, a new class of data mining methods, known as privacy preserving data mining (PPDM) algorithms, has been developed by the research community working on security and knowledge discovery. The aim of these
algorithms is the extraction of relevant knowledge from large amount of data, while protecting at the same time sensitive
information. Several data mining techniques, incorporating privacy protection mechanisms, have been developed that allow one
to hide sensitive itemsets or patterns, before the data mining process is executed. Privacy preserving classification methods,
instead, prevent a miner from building a classifier which is able to predict sensitive data. Additionally, privacy preserving
clustering techniques have been recently proposed, which distort sensitive numerical attributes, while preserving general
features for clustering analysis. A crucial issue is to determine which ones among these privacy-preserving techniques better
protect sensitive information. However, this is not the only criteria with respect to which these algorithms can be evaluated.
It is also important to assess the quality of the data resulting from the modifications applied by each algorithm, as well
as the performance of the algorithms. There is thus the need of identifying a comprehensive set of criteria with respect to
which to assess the existing PPDM algorithms and determine which algorithm meets specific requirements.
In this paper, we present a first evaluation framework for estimating and comparing different kinds of PPDM algorithms. Then,
we apply our criteria to a specific set of algorithms and discuss the evaluation results we obtain. Finally, some considerations
about future work and promising directions in the context of privacy preservation in data mining are discussed.
*The work reported in this paper has been partially supported by the EU under the IST Project CODMINE and by the Sponsors of
CERIAS.
Editor: Geoff Webb
相似文献
Elisa Bertino (Corresponding author)Email: |
Igor Nai FovinoEmail: |
Loredana Parasiliti ProvenzaEmail: |
108.
Carminic acid (CA) is a natural red pigment produced by Dactylopius coccus C. insects. It is widely used in the food industry to replace synthetic colourants. Despite being known for a long time, its antioxidant properties have not been studied so far. The aim of this study was to determine CA activities by different methods namely, free radical scavenging capacity against DPPH and ABTS radicals as well as its inhibition ability of β-carotene bleaching enzymatically induced by lipoxygenase (LOX). CA exhibited a remarkable antiradical activity similar to that of known antioxidants such as quercetin, ascorbic acid and trolox. Effectiveness of CA to protect β-carotene in the co-oxidation with linoleic acid is attributed to enzymatic inhibition of LOX rather than peroxyl radical trapping. 相似文献
109.
Elisa G. Doyagüez Francisco Parra Guillermo Corrales Alfonso Fernndez-Mayoralas Alberto Gallardo 《Polymer》2009,50(19):4438-4446
The synthesis of two new types of methacrylic polybetaines bearing trans-4-hydroxy-l-proline connected via its hydroxyl group is described, one with an aliphatic spacer of 6 carbon atoms and the other without any spacer. The pH sensitivity in aqueous media and the catalytic activity of the products in asymmetric aldol additions have been studied. The two polyzwitterions show an isoelectric point (IEP) close to 3. Swelling of networks prepared with the two monomers exhibit reversible pH sensitivity; the largest the pH distance from the IEP, the higher the net charge (positive or negative) and the higher the swelling. At basic pH and an ionic strength of 0.15, maximum swelling degrees of around 11 and 24 (g water/g polymer) have been found for the systems with and without spacer respectively. The polymers have been shown to be efficient catalysts for aldol reactions under homogeneous conditions in DMF but not in water. 相似文献
110.
Francesco Baino Elisa Fiume Jacopo Barberi Saeid Kargozar Juliana Marchi Jonathan Massera Enrica Verné 《International Journal of Applied Ceramic Technology》2019,16(5):1762-1796
Bioactive glasses exhibit the unique ability of bone bonding, thus creating a stable interface by stimulating bone cells toward mechanisms of regeneration and self-repair activated by ionic dissolution products. Therefore, 3D glass-derived scaffolds can be considered ideal porous templates to be used in bone tissue engineering strategies and regenerative medicine. This review provides a comprehensive overview of all technological aspects relevant to the fabrication of bioactive glass scaffolds, including the fundamentals of materials processing, a summary of the conventional porogen, and template-based methods and of recent additive manufacturing technologies, which are promising for large-scale production of highly reproducible and reliable implants suitable for a wide range of clinical applications. 相似文献