| 1. |
- Meyer, H., et al.
(author)
-
Overview of progress in European medium sized tokamaks towards an integrated plasma-edge/wall solution
- 2017
-
In: Nuclear Fusion. - : Institute of Physics Publishing (IOPP). - 0029-5515 .- 1741-4326. ; 57:10
-
Journal article (peer-reviewed)abstract
- Integrating the plasma core performance with an edge and scrape-off layer (SOL) that leads to tolerable heat and particle loads on the wall is a major challenge. The new European medium size tokamak task force (EU-MST) coordinates research on ASDEX Upgrade (AUG), MAST and TCV. This multi-machine approach within EU-MST, covering a wide parameter range, is instrumental to progress in the field, as ITER and DEMO core/pedestal and SOL parameters are not achievable simultaneously in present day devices. A two prong approach is adopted. On the one hand, scenarios with tolerable transient heat and particle loads, including active edge localised mode (ELM) control are developed. On the other hand, divertor solutions including advanced magnetic configurations are studied. Considerable progress has been made on both approaches, in particular in the fields of: ELM control with resonant magnetic perturbations (RMP), small ELM regimes, detachment onset and control, as well as filamentary scrape-off-layer transport. For example full ELM suppression has now been achieved on AUG at low collisionality with n = 2 RMP maintaining good confinement H-H(98,H-y2) approximate to 0.95. Advances have been made with respect to detachment onset and control. Studies in advanced divertor configurations (Snowflake, Super-X and X-point target divertor) shed new light on SOL physics. Cross field filamentary transport has been characterised in a wide parameter regime on AUG, MAST and TCV progressing the theoretical and experimental understanding crucial for predicting first wall loads in ITER and DEMO. Conditions in the SOL also play a crucial role for ELM stability and access to small ELM regimes.
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| 2. |
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| 3. |
- Backes, Claudia, et al.
(author)
-
Production and processing of graphene and related materials
- 2020
-
In: 2D Materials. - : IOP Publishing. - 2053-1583. ; 7:2
-
Journal article (peer-reviewed)abstract
- We present an overview of the main techniques for production and processing of graphene and related materials (GRMs), as well as the key characterization procedures. We adopt a 'hands-on' approach, providing practical details and procedures as derived from literature as well as from the authors' experience, in order to enable the reader to reproduce the results. Section I is devoted to 'bottom up' approaches, whereby individual constituents are pieced together into more complex structures. We consider graphene nanoribbons (GNRs) produced either by solution processing or by on-surface synthesis in ultra high vacuum (UHV), as well carbon nanomembranes (CNM). Production of a variety of GNRs with tailored band gaps and edge shapes is now possible. CNMs can be tuned in terms of porosity, crystallinity and electronic behaviour. Section II covers 'top down' techniques. These rely on breaking down of a layered precursor, in the graphene case usually natural crystals like graphite or artificially synthesized materials, such as highly oriented pyrolythic graphite, monolayers or few layers (FL) flakes. The main focus of this section is on various exfoliation techniques in a liquid media, either intercalation or liquid phase exfoliation (LPE). The choice of precursor, exfoliation method, medium as well as the control of parameters such as time or temperature are crucial. A definite choice of parameters and conditions yields a particular material with specific properties that makes it more suitable for a targeted application. We cover protocols for the graphitic precursors to graphene oxide (GO). This is an important material for a range of applications in biomedicine, energy storage, nanocomposites, etc. Hummers' and modified Hummers' methods are used to make GO that subsequently can be reduced to obtain reduced graphene oxide (RGO) with a variety of strategies. GO flakes are also employed to prepare three-dimensional (3d) low density structures, such as sponges, foams, hydro- or aerogels. The assembly of flakes into 3d structures can provide improved mechanical properties. Aerogels with a highly open structure, with interconnected hierarchical pores, can enhance the accessibility to the whole surface area, as relevant for a number of applications, such as energy storage. The main recipes to yield graphite intercalation compounds (GICs) are also discussed. GICs are suitable precursors for covalent functionalization of graphene, but can also be used for the synthesis of uncharged graphene in solution. Degradation of the molecules intercalated in GICs can be triggered by high temperature treatment or microwave irradiation, creating a gas pressure surge in graphite and exfoliation. Electrochemical exfoliation by applying a voltage in an electrolyte to a graphite electrode can be tuned by varying precursors, electrolytes and potential. Graphite electrodes can be either negatively or positively intercalated to obtain GICs that are subsequently exfoliated. We also discuss the materials that can be amenable to exfoliation, by employing a theoretical data-mining approach. The exfoliation of LMs usually results in a heterogeneous dispersion of flakes with different lateral size and thickness. This is a critical bottleneck for applications, and hinders the full exploitation of GRMs produced by solution processing. The establishment of procedures to control the morphological properties of exfoliated GRMs, which also need to be industrially scalable, is one of the key needs. Section III deals with the processing of flakes. (Ultra)centrifugation techniques have thus far been the most investigated to sort GRMs following ultrasonication, shear mixing, ball milling, microfluidization, and wet-jet milling. It allows sorting by size and thickness. Inks formulated from GRM dispersions can be printed using a number of processes, from inkjet to screen printing. Each technique has specific rheological requirements, as well as geometrical constraints. The solvent choice is critical, not only for the GRM stability, but also in terms of optimizing printing on different substrates, such as glass, Si, plastic, paper, etc, all with different surface energies. Chemical modifications of such substrates is also a key step. Sections IV-VII are devoted to the growth of GRMs on various substrates and their processing after growth to place them on the surface of choice for specific applications. The substrate for graphene growth is a key determinant of the nature and quality of the resultant film. The lattice mismatch between graphene and substrate influences the resulting crystallinity. Growth on insulators, such as SiO2, typically results in films with small crystallites, whereas growth on the close-packed surfaces of metals yields highly crystalline films. Section IV outlines the growth of graphene on SiC substrates. This satisfies the requirements for electronic applications, with well-defined graphene-substrate interface, low trapped impurities and no need for transfer. It also allows graphene structures and devices to be measured directly on the growth substrate. The flatness of the substrate results in graphene with minimal strain and ripples on large areas, allowing spectroscopies and surface science to be performed. We also discuss the surface engineering by intercalation of the resulting graphene, its integration with Si-wafers and the production of nanostructures with the desired shape, with no need for patterning. Section V deals with chemical vapour deposition (CVD) onto various transition metals and on insulators. Growth on Ni results in graphitized polycrystalline films. While the thickness of these films can be optimized by controlling the deposition parameters, such as the type of hydrocarbon precursor and temperature, it is difficult to attain single layer graphene (SLG) across large areas, owing to the simultaneous nucleation/growth and solution/precipitation mechanisms. The differing characteristics of polycrystalline Ni films facilitate the growth of graphitic layers at different rates, resulting in regions with differing numbers of graphitic layers. High-quality films can be grown on Cu. Cu is available in a variety of shapes and forms, such as foils, bulks, foams, thin films on other materials and powders, making it attractive for industrial production of large area graphene films. The push to use CVD graphene in applications has also triggered a research line for the direct growth on insulators. The quality of the resulting films is lower than possible to date on metals, but enough, in terms of transmittance and resistivity, for many applications as described in section V. Transfer technologies are the focus of section VI. CVD synthesis of graphene on metals and bottom up molecular approaches require SLG to be transferred to the final target substrates. To have technological impact, the advances in production of high-quality large-area CVD graphene must be commensurate with those on transfer and placement on the final substrates. This is a prerequisite for most applications, such as touch panels, anticorrosion coatings, transparent electrodes and gas sensors etc. New strategies have improved the transferred graphene quality, making CVD graphene a feasible option for CMOS foundries. Methods based on complete etching of the metal substrate in suitable etchants, typically iron chloride, ammonium persulfate, or hydrogen chloride although reliable, are time- and resource-consuming, with damage to graphene and production of metal and etchant residues. Electrochemical delamination in a low-concentration aqueous solution is an alternative. In this case metallic substrates can be reused. Dry transfer is less detrimental for the SLG quality, enabling a deterministic transfer. There is a large range of layered materials (LMs) beyond graphite. Only few of them have been already exfoliated and fully characterized. Section VII deals with the growth of some of these materials. Amongst them, h-BN, transition metal tri- and di-chalcogenides are of paramount importance. The growth of h-BN is at present considered essential for the development of graphene in (opto) electronic applications, as h-BN is ideal as capping layer or substrate. The interesting optical and electronic properties of TMDs also require the development of scalable methods for their production. Large scale growth using chemical/physical vapour deposition or thermal assisted conversion has been thus far limited to a small set, such as h-BN or some TMDs. Heterostructures could also be directly grown. Section VIII discusses advances in GRM functionalization. A broad range of organic molecules can be anchored to the sp(2) basal plane by reductive functionalization. Negatively charged graphene can be prepared in liquid phase (e.g. via intercalation chemistry or electrochemically) and can react with electrophiles. This can be achieved both in dispersion or on substrate. The functional groups of GO can be further derivatized. Graphene can also be noncovalently functionalized, in particular with polycyclic aromatic hydrocarbons that assemble on the sp(2) carbon network by pi-pi stacking. In the liquid phase, this can enhance the colloidal stability of SLG/FLG. Approaches to achieve noncovalent on-substrate functionalization are also discussed, which can chemically dope graphene. Research efforts to derivatize CNMs are also summarized, as well as novel routes to selectively address defect sites. In dispersion, edges are the most dominant defects and can be covalently modified. This enhances colloidal stability without modifying the graphene basal plane. Basal plane point defects can also be modified, passivated and healed in ultra-high vacuum. The decoration of graphene with metal nanoparticles (NPs) has also received considerable attention, as it allows to exploit synergistic effects between NPs and graphene. Decoration can be either achieved chemically or in the gas phase. All LMs,
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| 4. |
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| 5. |
- Bombarda, F., et al.
(author)
-
Runaway electron beam control
- 2019
-
In: Plasma Physics and Controlled Fusion. - : IOP Publishing. - 1361-6587 .- 0741-3335. ; 61:1
-
Journal article (peer-reviewed)
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| 6. |
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| 7. |
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| 8. |
- Datta, Shuvo Jit, et al.
(author)
-
Removal of Sr-90 from highly Na+-rich liquid nuclear waste with a layered vanadosilicate
- 2019
-
In: Energy & Environmental Science. - : Royal Society of Chemistry (RSC). - 1754-5692 .- 1754-5706. ; 12:6, s. 1857-1865
-
Journal article (peer-reviewed)abstract
- Capture of trace amounts (parts per trillion or ppt level) of Sr-90 from highly Na+-rich (5 M or 115 000 parts per million) liquid wastes produced from reprocessing of spent nuclear fuel rods is crucial for continuous operation of nuclear power plants. However, no sorbents have shown such abilities. We now report that a novel layered vanadosilicate, SGU-7, with the unit cell parameters of a = 23.58 A, b = 30.04 A, c = 12.31 A, b = 100.28, and space group of P12(1)/a1, can effectively capture Sr-90 from a 5 M Na+ solution containing 6.2 ppt of Sr-90. It also effectively captures 1-ppb level Ra-226 from 2 M NaCl solution, and Cs+ and Sr2+ from groundwater, demonstrating that it can be immediately used to remedy groundwater and soil contaminated with Ra-226, Sr-90, and Cs-137.
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| 9. |
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| 10. |
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| 11. |
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| 12. |
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| 13. |
- Gao, Zihao Rei, et al.
(author)
-
HPM-14 : A New Germanosilicate Zeolite with Interconnected Extra-Large Pores Plus Odd-Membered and Small Pores
- 2021
-
In: Angewandte Chemie International Edition. - : Wiley. - 1433-7851 .- 1521-3773. ; 60:7, s. 3438-3442
-
Journal article (peer-reviewed)abstract
- HPM-14 is a new extra-large pore zeolite synthesized using imidazolium-based organic structure-directing agents (SDAs), fluoride anions, and germanium and silicon as tetrahedral components of the framework. Owing to the presence of stacking disorder, the structure elucidation of HPM-14 was challenging, and different techniques were necessary to clarify the details of the structure and to understand the nature of the disorder. The structure has been solved by three-dimensional electron-diffraction technique (3D ED) and consists of an intergrowth of two polymorphs possessing a three-dimensional channel system, including an extra-large pore opened through windows made up of sixteen tetrahedral atoms (16-membered ring, 16MR) as well as two additional sets of odd-membered (9MR) and small (8MR) pores. The intergrowth has been studied by scanning transmission electron microscopy (C-s-STEM) and powder X-ray diffraction simulations (DIFFaX), which show a large predominance of the monoclinic polymorph A.
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| 14. |
- Han, Lu, et al.
(author)
-
Silica-Based Nanoporous Materials
- 2014
-
In: Zeitschrift für Anorganische und Allgemeines Chemie. - : Wiley. - 0044-2313 .- 1521-3749. ; 640:3-4, s. 521-536
-
Research review (peer-reviewed)abstract
- Ordered nanoporous structures are among the most fascinating and industrially important materials currently in use. The archetypal zeolite material has now been joined by an eclectic array of new structures that exhibit porosity over a wide range of length scales and with order/disorder expressed in a multitude of ways. This raises the bar in terms of characterization and extends a real challenge to the scientific community to fully understand the properties and potential future applications of such materials. In this review we discuss the importance of modern microscopy tools combined with diffraction in this endeavour and show how the details of even the most complex quasi-crystalline nanoporous architectures can be elucidated. We show by using the appropriate spherical aberration (C-s) corrections in scanning transmission electron microscopy it is possible to decipher all the individual silicon and aluminum atoms in a zeolite structure. Automated routines for using large electron diffraction datasets for crystal structure determination of nanocrystals is described making the need for large single crystal synthesis less-and-less important. The power of complementary combinations of surface tools such as atomic force microscopy and high-resolution scanning electron microscopy is discussed to elucidate crystal growth mechanisms. For mesoporous materials synthesized from self-organized organic mesophases electron microscopy reveals the details of the complex hierarchy of porosity so crucial for the functional performance of the structure.
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| 15. |
- Joffrin, E., et al.
(author)
-
Overview of the JET preparation for deuterium-tritium operation with the ITER like-wall
- 2019
-
In: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 59:11
-
Research review (peer-reviewed)abstract
- For the past several years, the JET scientific programme (Pamela et al 2007 Fusion Eng. Des. 82 590) has been engaged in a multi-campaign effort, including experiments in D, H and T, leading up to 2020 and the first experiments with 50%/50% D-T mixtures since 1997 and the first ever D-T plasmas with the ITER mix of plasma-facing component materials. For this purpose, a concerted physics and technology programme was launched with a view to prepare the D-T campaign (DTE2). This paper addresses the key elements developed by the JET programme directly contributing to the D-T preparation. This intense preparation includes the review of the physics basis for the D-T operational scenarios, including the fusion power predictions through first principle and integrated modelling, and the impact of isotopes in the operation and physics of D-T plasmas (thermal and particle transport, high confinement mode (H-mode) access, Be and W erosion, fuel recovery, etc). This effort also requires improving several aspects of plasma operation for DTE2, such as real time control schemes, heat load control, disruption avoidance and a mitigation system (including the installation of a new shattered pellet injector), novel ion cyclotron resonance heating schemes (such as the three-ions scheme), new diagnostics (neutron camera and spectrometer, active Alfven eigenmode antennas, neutral gauges, radiation hard imaging systems...) and the calibration of the JET neutron diagnostics at 14 MeV for accurate fusion power measurement. The active preparation of JET for the 2020 D-T campaign provides an incomparable source of information and a basis for the future D-T operation of ITER, and it is also foreseen that a large number of key physics issues will be addressed in support of burning plasmas.
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| 16. |
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| 17. |
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| 18. |
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| 19. |
- Li, Jian, et al.
(author)
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A 3D extra-large-pore zeolite enabled by 1D-to-3D topotactic condensation of a chain silicate
- 2023
-
In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 379:6629, s. 283-287
-
Journal article (peer-reviewed)abstract
- Zeolites are microporous silicates with a large variety of applications as catalysts, adsorbents, and cation exchangers. Stable silica-based zeolites with increased porosity are in demand to allow adsorption and processing of large molecules but challenge our synthetic ability. We report a new, highly stable pure silica zeolite called ZEO-3, which has a multidimensional, interconnected system of extra-large pores open through windows made by 16 and 14 silicate tetrahedra, the least dense polymorph of silica known so far. This zeolite was formed by an unprecedented one-dimensional to three-dimensional (1D-to-3D) topotactic condensation of a chain silicate. With a specific surface area of more than 1000 square meters per gram, ZEO-3 showed a high performance for volatile organic compound abatement and recovery compared with other zeolites and metal-organic frameworks.
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| 20. |
- Mayoral, Alvaro, et al.
(author)
-
Direct Atomic-Level Imaging of Zeolites : Oxygen, Sodium in Na-LTA and Iron in Fe-MFI
- 2020
-
In: Angewandte Chemie International Edition. - : Wiley. - 1433-7851 .- 1521-3773. ; 59:44, s. 19510-19517
-
Journal article (peer-reviewed)abstract
- Zeolites are becoming more versatile in their chemical functions through rational design of their frameworks. Therefore, direct imaging of all atoms at the atomic scale, basic units (Si, Al, and O), heteroatoms in the framework, and extra-framework cations, is needed. TEM provides local information at the atomic level, but the serious problem of electron-beam damage needs to be overcome. Herein, all framework atoms, including oxygen and most of the extra-framework Na cations, are successfully observed in one of the most electron-beam-sensitive and lowest framework density zeolites, Na-LTA. Zeolite performance, for instance in catalysis, is highly dependent on the location of incorporated heteroatoms. Fe single atomic sites in theMFIframework have been imaged for the first time. The approach presented here, combining image analysis, electron diffraction, and DFT calculations, can provide essential structural keys for tuning catalytically active sites at the atomic level.
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| 21. |
- Mayoral, Alvaro, et al.
(author)
-
Synthesis of copper chloride nanowires by thermal treatment in the presence of zeolite X
- 2010
-
In: CrystEngComm. - : Royal Society of Chemistry (RSC). - 1466-8033. ; 12:10, s. 3012-3018
-
Journal article (peer-reviewed)abstract
- Copper(I) chloride nanowires have been synthesized by heating the salt in the presence of copper zeolite X (FAU structure type). Their structure and composition were studied by powder X-ray diffraction, transmission electron microscopy and energy dispersive X-ray spectroscopy. Wire growth was found to be dependent on a number of factors, the most important being the temperature of the reaction. The mechanism of wire growth, involving the occlusion of CuCl within the zeolite pores, is discussed.
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| 22. |
- Meyer, H., et al.
(author)
-
Overview of progress in European medium sized tokamaks towards an integrated plasma-edge/wall solution
- 2017
-
In: Nuclear Fusion. - : Institute of Physics Publishing (IOPP). - 0029-5515 .- 1741-4326. ; 57:10
-
Journal article (peer-reviewed)abstract
- Integrating the plasma core performance with an edge and scrape-off layer (SOL) that leads to tolerable heat and particle loads on the wall is a major challenge. The new European medium size tokamak task force (EU-MST) coordinates research on ASDEX Upgrade (AUG), MAST and TCV. This multi-machine approach within EU-MST, covering a wide parameter range, is instrumental to progress in the field, as ITER and DEMO core/pedestal and SOL parameters are not achievable simultaneously in present day devices. A two prong approach is adopted. On the one hand, scenarios with tolerable transient heat and particle loads, including active edge localised mode (ELM) control are developed. On the other hand, divertor solutions including advanced magnetic configurations are studied. Considerable progress has been made on both approaches, in particular in the fields of: ELM control with resonant magnetic perturbations (RMP), small ELM regimes, detachment onset and control, as well as filamentary scrape-off-layer transport. For example full ELM suppression has now been achieved on AUG at low collisionality with n = 2 RMP maintaining good confinement H-H(98,H-y2) approximate to 0.95. Advances have been made with respect to detachment onset and control. Studies in advanced divertor configurations (Snowflake, Super-X and X-point target divertor) shed new light on SOL physics. Cross field filamentary transport has been characterised in a wide parameter regime on AUG, MAST and TCV progressing the theoretical and experimental understanding crucial for predicting first wall loads in ITER and DEMO. Conditions in the SOL also play a crucial role for ELM stability and access to small ELM regimes.
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| 23. |
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| 24. |
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| 25. |
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| 26. |
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| 27. |
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| 28. |
- Serra, Elias, et al.
(author)
-
Immobilization of lipase in ordered mesoporous materials : Effect of textural and structural parameters
- 2008
-
In: Microporous and Mesoporous Materials. - : Elsevier BV. - 1387-1811 .- 1873-3093. ; 114:03-jan, s. 201-213
-
Journal article (peer-reviewed)abstract
- A systematic study dealing with the influence of several parameters oil the immobilization of lipase in ordered mesoporous materials (OMM) is presented here. In a first step, a series of OMM have been synthesized trying to cover the most relevant structures. The aim is to get variation in the key properties susceptible of influencing their behavior as lipase supports, such as the structure (cubic or hexagonal), the nature of the pores (channel-like or cage-like), the connectivity of the porous network and the pore size. Also, by following the co-condensation technique, 5-10%-methylated analogues of the pure-silica materials have been prepared. All the samples have been fully characterized with XRD, TEM (including 3D reconstruction), SEM, TGA and N-2 isotherms, and the incorporation of the organic function has been demonstrated by Si-29 NMR. All of them have been tested as supports in the immobilization of Candida antarctica Lipase B (CaLB) and the leaching of the enzyme in aqueous media evaluated. With such a systematic approach, valuable information on the influence of the textural properties and the nature of the porous network oil the yields of immobilization and enzyme desorption have been stated. Very interestingly, leaching of the enzyme can be diminished until it practically disappears without being covalently bonded to the wall, which places the ordered mesoporous materials at the starting point of a new scenario in enzyme immobilization on preexisting supports.
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| 29. |
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| 30. |
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| 31. |
- Villaescusa, Luis A., et al.
(author)
-
Sandwich-Type Zeolite Intergrowths with MFI and the Novel Extra-Large Pore IDM-1 as Ordered End-Members
- 2021
-
In: Chemistry of Materials. - : American Chemical Society (ACS). - 0897-4756 .- 1520-5002. ; 33:19, s. 7869-7877
-
Journal article (peer-reviewed)abstract
- Stacking faults are two-dimensional planar defects frequently arising in zeolites, modifying their properties and potentially affecting their performance in catalysis and separation applications. In classical zeolite intergrowths, a topologically unique zeolite layer may often pile up after some spatial transformation (lateral translation, rotation, and/or reflection) that may occur in different amounts or directions with about similar probabilities, leading to a difficult to control disorder. Here, we present a new kind of zeolite intergrowth that requires an additional topologically distinct layer rather than a spatial transformation of a unique one. Stacking of the so-called pentasil layers produces the well-known medium pore zeolite MFI. Intercalation in strict alternation of a topologically distinct second layer sandwiched between pentasil layers expands the structure to produce the new extra-large pore IDM-1. Stacking disorder modulates the structural expansion along the stacking direction. The disordered materials have been studied by simulation of the X-ray diffraction patterns using the program DIFFaX and by Cs-corrected high-resolution electron microscopy. We show that disorder does not occur at random but in extended domains and can be controlled all the way from MFI to IDM-1 by just varying the concentration of the synthesis mixture.
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| 32. |
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| 33. |
- Willhammar, Tom, et al.
(author)
-
3D reconstruction of atomic structures from high angle annular dark field (HAADF) STEM images and its application on zeolite silicalite-1
- 2014
-
In: Dalton Transactions. - : Royal Society of Chemistry (RSC). - 1477-9226 .- 1477-9234. ; 43:37, s. 14158-14163
-
Journal article (peer-reviewed)abstract
- High-resolution transmission electron microscopy (HRTEM) has shown to be very powerful for solving three-dimensional (3D) structures of unknown crystals. HRTEM has a unique advantage over diffraction for solving structures. Crystallographic structure factor phases, which are lost in diffraction can be directly obtained from HRTEM images. For the determination of a 3D crystalline structure by HRTEM, the crystallographic structure factor amplitudes and phases extracted from HRTEM images along different zone axes are combined to reconstruct a 3D electrostatic potential map. In recent years, scanning transmission electron microscopy (STEM) has reached the atomic resolution, which is comparable to that of HRTEM. Here we show, for the first time, that the structure factor phases can be also obtained from high angle annular dark-field (HAADF)-STEM images and used for 3D reconstruction of atomic structures. This is applied to the complex zeolite structure, silicalite-1 (Formula SiO2, framework code MFI, Pnma, a = 20.090 angstrom, b = 19.738 angstrom and c = 13.142 angstrom). We have compared the amplitudes and phases obtained from HAADF-STEM images with those from HRTEM images.
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| 34. |
- Zeyer, Albert, et al.
(author)
-
Adressing complexity in Science|Environment|Health pedagogy
- 2019
-
In: Bridging Research and Practice in Science Education. - Cham : Springer. - 9783030172190 - 9783030172183 ; , s. 153-170
-
Conference paper (peer-reviewed)abstract
- This paper aims to discuss complexity as a key feature for understanding the role of science knowledge in environmental and health contexts – a core issue in Science|Environment|Health pedagogy. Complex systems are, in principle, not predictable. In different contexts, ephemeral mechanisms produce different, sometimes completely unexpected results. The “art of decision making” in complex contexts is to take scientific knowledge into account, but to interpret its meaning in terms of concrete complex contexts. This is illustrated by four empirical studies on Science|Environment|Health issues, presented midway through this paper. The findings underscore the importance of introducing complexity issues into science education. Not only are all the grand health and environmental challenges of our times highly complex, but there is also evidence that introducing complexity into science education may motivate many students for science learning and change practice in science classrooms. Truly appreciating the role of complexity in Science|Environment|Health pedagogy is likely to raise future citizens who understand the delicate relation between predictability and uncertainty and to empower them for wise decisions about societal and personal well-being.
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| 35. |
- Zeyer, Albert, et al.
(author)
-
Two-Eyed Seeing and Scientific Holism in a New Science|Environment|Health Pedagogy
- 2024
-
Other publication (other academic/artistic)abstract
- Science|Environment|Health (S|E|H) is a new science pedagogy that aims at promoting the mutual benefit between the three educational fields of science education, environmental education, and health education. Holism and its conceptualisation has become an important topic in recent S|E|Hwork. In this paper, featuring the invited symposium of the ESERA special interest group 4 at the ESERA conference 2021, we suggest the concept of Two-Eyed Seeing as a basis for the definition of scientific holism in S|E|H. Two-Eyed Seeing as a metaphor was introduced by science education researchers working with Canadian aborigines. Based on Sellars’s concept of stereoscopic view, we conceptualize Two-Eyed Seeing in S|E|H through an ontological framework. We define scientificholism as the “eye switch” from the scientific image to students’ life-world image, a transition that we consider as equally important as the - more common - reductionist “eye switch” from students’ life-worlds back to the scientific image. Two-Eyed Seeing may then be understood as a continuouscirculation of repeated “eye switches” between life-world image and scientific image. We illustrate this approach by three symposium contributions - communicating the meta-organism in school, scientific holism against eco- and health depression, and a holistic visual tool to approach S|E|H competences – and we discuss consequences for teaching and research in science education. We point out that, in a new S|E|H pedagogy and beyond, Two-Eyed Seeing may be a helpful extension to the well-established socio-scientific issues approach. © 2022 by the Author(s).
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| 36. |
- Zeyer, Albert, et al.
(author)
-
Two-Eyed Seeing and Scientific Holism in A New Science|Environment|Health Pedagogy
- 2023
-
In: Fostering Scientific Citizenship in an Uncertain World. - Cham, Switzerland : Springer. - 9783031322242 - 9783031322273 - 9783031322259 ; , s. 293-309
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Book chapter (peer-reviewed)abstract
- Science|Environment|Health (S|E|H) is a new science pedagogy that aims at promoting the mutual benefit between the three educational fields of science education, environmental education, and health education. Holism and its conceptualisation have become an important topic in recent S|E|H work. In this paper, featuring the invited symposium of the ESERA special interest group 4 at the ESERA conference 2021, we suggest the concept of Two-Eyed Seeing as a basis for the definition of scientific holism in S|E|H. Two-Eyed Seeing as a metaphor was introduced by science education researchers working with Canadian Indigenous citizens. Based on Sellars’s concept of stereoscopic view, we conceptualise Two-Eyed Seeing in S|E|H through an ontological framework. We define scientific holism as the “eye switch” from the scientific image to students’ life-world image, a transition that we consider as equally important as the – more common – reductionist “eye switch” from students’ life-worlds back to the scientific image. Two-Eyed Seeing may then be understood as a continuous circulation of repeated “eye switches” between life-world image and scientific image. We illustrate this approach through three symposium contributions – communicating the meta-organism in school, scientific holism against eco- and health depression, and a holistic visual tool to approach S|E|H competencies – and we discuss consequences for teaching and research in science education. Finally, we point out that, in a new S|E|H pedagogy and beyond, Two-Eyed Seeing may be a helpful extension to the well-established socio-scientific issues approach. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
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| 37. |
- Zhang, Qing, et al.
(author)
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Electron Microscopy Studies of Local Structural Modulations in Zeolite Crystals
- 2020
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In: Angewandte Chemie. - : Wiley. - 0044-8249 .- 1521-3757. ; 132:44, s. 19571-19581
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Research review (peer-reviewed)abstract
- Zeolites are widely used in catalysis, gas separation, ion exchange, etc. due to their superior physicochemical properties, which are closely related to specific features of their framework structures. Although more than two hundred different framework types have been recognized, it is of great interest to explore from a crystallographic perspective, the atomic positions, surface terminations, pore connectivity and structural defects that deviate from the ideal framework structures, namely local structural modulation. In this article, we review different types of local modulations in zeolite frameworks using various techniques, especially electron microscopy (EM). The most recent advances in resolving structural information at the atomic level with aberration corrected EM are also presented, commencing a new era of gaining atomic structural information, not only for all tetrahedral atoms including point vacancies in framework but also for extra-framework cations and surface terminations.
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| 38. |
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- 2018
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In: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 58:1
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Research review (peer-reviewed)
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