1,720,952 research outputs found
CO<sub>2</sub> utilization in chemical looping gasification and co-gasification of lignocellulosic biomass components over iron-based oxygen carriers: Thermogravimetric behavior, synergistic effect, and reduction characteristics
No full textEfficient CO2 utilization in the thermochemical conversion of biomass plays an important role in creating a future low-carbon economy. This study attempts to explore the CO2-assisted chemical looping gasification and co-gasification process of lignocellulosic biomass components (hemicellulose, cellulose, and lignin) with iron oxide oxygen carriers using thermogravimetry and differential thermal analysis. Three different iron oxide oxygen carrier-to-biomass (O/B) ratios were taken into account to deeply understand the thermal degradation characteristics of individual components (O/B ratio: 0) and their blending with iron oxide oxygen carriers (O/B ratio: 0.5 and 1). Meanwhile, the reduction characteristics of three major biomass components were also investigated in terms of X-ray diffraction (XRD), synergistic interaction, and reduction degree. Experimental results suggest that the existence of iron oxide oxygen carriers could accelerate the reaction kinetics under the reactive CO2 environment, arising from the competitive relationship between the direct reduction reaction by char in biomass and the Boudouard reaction at high temperatures (600–950 °C). Interestingly, the reoxidation behavior of the reduced iron oxide is observed at high temperatures, especially for lignin. Among all the tested biomass materials, their ability to reduce iron oxide oxygen carriers under the CO2 atmosphere follows the order of biomass mixture (1:1:1 wt%)>lignin>xylan>cellulose. Moreover, the findings indicate that significant synergistic interaction exists during the CO2-assisted chemical looping co-gasification process.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Energy Technolog
Fe3O4–β-cyclodextrin–chitosan bionanocomposite for arsenic removal from aqueous solution
No full textCommunication—sulfonated poly (ether ether ketone) as cation exchange membrane for alkaline redox flow batteries
No full textA sulfonated poly (ether ether ketone) (sPEEK) was tested as the separator in a full alkaline flow battery with 2,6-dihydroxyanthraquinone-ferro/ferricyanide, DHAQ-FeCy, redox couples. Cell performance was compared to that of an identical cell utilizing a perfluorosulfonic acid (PFSA) membrane. Replacement of the PFSA membrane with sPEEK resulted in a 10% power density increase, a 40% decrease in capacity loss per day and an 85-fold decrease in ferricyanide permeation. Though long-term stability of sPEEK in alkaline media requires improvement, these results highlight the potential to produce non-fluorinated membranes with better performance in organic redox flow batteries than the commercially available PFSAs. © The Author(s) 2018
Harmonization of land registry in Europe
No full textAn increase in cross-border transactions of immovable property within the European Union puts a demand for easy access to the information of the national land administrations of the member states. The European Union Land Information System (EULIS) project brings together the registrations of eight European jurisdictions in one portal. In this way it provides cross-border access to information about the rights on real estate, using the information in thecomputerized databases of the participating land registries. The EULIS project is the first step towards a more transparent system of real estate transactions. The next logical step, from the viewpoint of international accessibility of the information, is that the national land registries within the united Europe will be harmonized or even integrated in one European land registry or administration.In order to promote cross-border transactions and to facilitate the European mortgage market the authors suggest the introduction of a common way of land registration, in addition to the existing national land registrations: the EuroTitle system. This is a challenging concept, which may bring the required uniformity of land registration in Europe. This approach is in the beginning stages of development and the legal and organisational consequences need to be further explored and developed in order to assess the feasibility of the introduction of such a concept in European land registry.OLD Geo-information and Land Developmen
A convenient synthesis of some arylated phenylsulfonylacetonitriles and ethyl cyanoacetates using organoiron complexes.
No full textA general method for the synthesis of some arylated phenylsulphonylacetonitriles 6a–g, 10a, b and 16 and ethyl cyanoacetates 7a-d and 11a, b is described. Nucleophilic substitution of the cyclopentadienyliron complexes of chloroarenes 1a–g with phenylsulphonylacetonitrile 2 or ethyl cyanoacetate 3 in the presence of potassium carbonate in DMF, at room temperature under a nitrogen atmosphere gave cyclopentadienyliron complexes of arylated phenylsulphonylacetonitriles 4a–g, 8a, b and 15 and ethyl cyanoacetates 5a–d and 9a, b in very good yields (71–94%). Photolysis of these complexes liberated the arenes (70–91%). To demonstrate the versatility of this methodological approach, reactions of both carbon nucleophiles 2, 3 with dimethyl chlorobenzene complexes 1h, j gave the desired products 8a, 9a, 12 and 13 without significant steric effect. This synthesis is advantageous over all those previously reported and should be a practical route to a variety of alkanoic acid and heterocyclic precursors
Trans-4-tert-Butyl-3-hydroxy-5-cyclohepten-1-one (I) and trans-6-tert-butyl-3-hydroxy-2,7-dimethyl-4-cyclohepten-1-one (II).
No full text(2) C~H1802, Mr=182"3, monoclinic,
P21/a, a = 7.463 (3), b = 9.776 (3), c = 14-955 (5) A,
fl = 97.33 °, V = 1082-2 A 3, Z = 4, Dx = 1.12 gcm -3,
a(Mo Ka) = 0.71073/~, ~ = 0.70 cm-i, F(000) =
400, room temperature, R = 0.041 for 480 observed
reflections. (5) CI3H2202, Mr = 210-3, orthorhombic,
Pnab, a = 9.747 (1), b = 10.724 (2), c = 24.365 (4) A,
V = 2546-8 A 3, Z = 8, Dx = 1-10 g cm -3, A(Mo Kce)
= 0.71073 A, /z = 0.67 cm-l, F(000) = 928, room
temperature, R = 0.037 for 521 observed reflections.
In both (2) and (5) the hydroxyl group is trans with
respect to the tert-butyl group. In (2) pairs of
molecules are linked via hydrogen bonds [O...O
(1-x, I-y, I-z) 2.809 (7)A] to form centrosymmetric
dimers, while in (5) molecules are hydrogen
bonded [O-..O(x, -0.5+y, 1.5-z) 2.847 (7) A]
through 21 screw axes to form infinite chains. The
highly strained seven-membered ring in (2) has a
boat-type conformation and in (5) it has a sofa-type
conformation
How can Early Warning Signs contribute to the predictability of potential cost overruns in public infrastructure road works under integrated contracts, so that costs can be reduced for the contractor?
No full textCivil Engineering and GeosciencesStructural Engineerin
Ironcyclopentadienyl mediated 2-alkyl-2-arylphenylsulphonylacetonitrile synthesis
No full textA unique route to the synthesis of 2-alkyl-2-arylphenylsulphonylacetonitriles via the nucleophilic aromatic substitution (SNAr) of chloroarene cyclopentadienyliron complexes with 2-alkyl phenylsulphonylacetonitriles has been investigated. Reactions of chloroarene complexes (1a–d) with 2-alkyl phenylsulphonylacetonitrile (2a,b) in the presence of K2CO3 in DMF at room temperature led to the formation of complexes 3a–d and 4a,c,d in good yields. The use of alkylated phenylsulphonylacetonitriles as nucleophiles in the reactions with the p-dichlorobenzene complex (1e) allowed the formation of the disubstituted complexes (5,6). Photolytic demetallation provided an efficient route to the liberation of the arylated phenylsulphonylacetonitriles 7a–d, 8a,c,d, 9, and 10. Keywords: chloroarene, phenylsulphonylacetonitrile, nucleophilic substitution
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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