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A new zeolite (named as ITQ-52) having large cavities and small and medium channels has been synthesized. This was achieved by using a new family of amino-phosphonium cations as organic structure directing agents (OSDA). These cations contain P−C and P−N bonds, and therefore they lie between previously reported P-containing OSDA, such as tetraalkylphosphonium and phosphazenes. In this study, it has been found that 1,4- butanediylbis[tris(dimethylamino)]phosphonium dication is a very efficient OSDA for crystallization of several zeolites, and in some particular conditions, the new zeolite ITQ-52 was synthesized as a pure phase. The structure of ITQ-52 has been solved using high-resolution synchrotron X-ray powder diffraction data of the calcined solid. This new zeolite crystallizes in the space group I2/m, with cell parameters a = 17.511 Å, b = 17.907 Å, c = 12.367 Å, and β = 90.22°. The topology of ITQ-52 can be described as a replication of a composite building unit with ring notation [435461] that gives rise to the formation of an interconnected 8R and 10R channel system. ; We thank financial support by the Spanish Government (MAT2012-38567-C02-01, MAT2012-38567-C02-02, Consolider Ingenio 2010-Multicat CSD-2009-00050 and Severo Ochoa SEV-2012-0267). R.S. acknowledges to UPV for a FPI predoctoral fellowship. Authors thank ALBA Light Source for beam allocation at beamline MSPD. We thank G. Sastre and J. A. Vidal for computational calculations and MAS NMR experiments, respectively. ; Simancas Coloma, R.; Jorda Moret, JL.; Rey Garcia, F.; Corma Canós, A.; Cantin Sanz, A.; Peral, I.; Popescu, C. (2014). A new microporous zeolitic silicoborate (ITQ-52) with interconnected small and medium pores. Journal of the American Chemical Society. 136(9):3342-3345. doi:10.1021/ja411915c ; S ; 3342 ; 3345 ; 136 ; 9

The synthesis of the ZSM-5 and beta zeolites in their nanosized form has been achieved by using simple alkyl-substituted mono-cationic cyclic ammonium cations as OSDA molecules. The particular combination of a cyclic fragment and a short linear alkyl-chain group (preferentially C) within the monocationic OSDA molecules allows directing the crystallization of nanosized zeolites with excellent solid yields (above 90%). Interestingly, the formation of the nanosized ZSM-5 and beta zeolites mostly depends on the size and nature of the cyclic fragment of the OSDA molecule, resulting in all cases in nanocrystalline solids with homogeneous distributions of particle sizes (∼10-25 nm) and controlled Si/Al molar ratios (∼15-30). The achieved nanosized ZSM-5 and beta zeolites have been extensively characterized by different techniques to study their physico-chemical properties, such as chemical composition, pore accessibility or Brønsted acidity, among others. Moreover, the catalytic properties of the nanosized ZSM-5 and beta zeolites have been evaluated for different chemical reactions, including methanol-to-olefins (MTO) in the case of ZSM-5, and alkylation of benzene with propylene to obtain cumene and oligomerization of light olefins to liquid fuels in the case of beta, observing in all cases improved catalytic activity and product selectivity towards target products when compared to related catalysts. ; This work has been supported by the Spanish Government MINECO through "Severo Ochoa" (SEV 2012-0267), MAT2015-71261-R and CTQ2015-70126-R, by the European Union through ERC-AdG-2014-671093 (SynCatMatch) and by the Fundación Ramón Areces through a research contract of the "Life and Materials Science" program. E. M. G. and M. R. D- R. acknowledge "La Caixa – Severo Ochoa" International PhD Fellowships (call 2015). M. E. M- A. thanks MINECO for economical support through pre-doctoral fellowship (BES-2013-066800). ; Peer Reviewed

[EN] The synthesis of the ZSM-5 and beta zeolites in their nanosized form has been achieved by using simple alkyl-substituted mono-cationic cyclic ammonium cations as OSDA molecules. The particular combination of a cyclic fragment and a short linear alkyl-chain group (preferentially C4) within the monocationic OSDA molecules allows directing the crystallization of nanosized zeolites with excellent solid yields (above 90%). Interestingly, the formation of the nanosized ZSM-5 and beta zeolites mostly depends on the size and nature of the cyclic fragment of the OSDA molecule, resulting in all cases in nanocrystalline solids with homogeneous distributions of particle sizes (similar to 10-25 nm) and controlled Si/Al molar ratios (similar to 15-30). The achieved nanosized ZSM-5 and beta zeolites have been extensively characterized by different techniques to study their physico-chemical properties, such as chemical composition, pore accessibility or Bronsted acidity, among others. Moreover, the catalytic properties of the nanosized ZSM-5 and beta zeolites have been evaluated for different chemical reactions, including methanol-to-olefins (MTO) in the case of ZSM-5, and alkylation of benzene with propylene to obtain cumene and oligomerization of light olefins to liquid fuels in the case of beta, observing in all cases improved catalytic activity and product selectivity towards target products when compared to related catalysts. ; This work has been supported by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), MAT2015-71261-R and CTQ2015-70126-R, by the European Union through ERC-AdG-2014-671093 (SynCatMatch) and by the Fundacion Ramon Areces through a research contract of the "Life and Materials Science" program. E. M. G. and M. R. D-R. acknowledge "La Caixa - Severo Ochoa" International PhD Fellowships (call 2015). M. E. M-A. thanks MINECO for economical support through pre-doctoral fellowship (BES-2013-066800). The Electron Microscopy Service of the UPV is acknowledged for their help in sample ...

The synthesis of crystalline microporous materials containing large pores is in high demand by industry, especially for the use of these materials as catalysts in chemical processes involving bulky molecules. An extra-large-pore silicoaluminophosphate with 16-ring openings, ITQ-51, has been synthesized by the use of bulky aromatic proton sponges as organic structure-directing agents. Proton sponges show exceptional properties for directing extra-large zeolites because of their unusually high basicity combined with their large size and rigidity. This extra-large-pore material is stable after calcination, being one of the very few examples of hydrothermally stable molecular sieves containing extra-large pores. The structure of ITQ-51 was solved from submicrometer-sized crystals using the rotation electron diffraction method. Finally, several hypothetical zeolites related to ITQ-51 have been proposed. ; The authors gratefully acknowledge Dr. Alejandro Vidal-Moya for the SUP>27 /SUP>Al MQ MAS NMR experiment. The authors also acknowledge financial support from Ministerio de Economia y Competitividad of Spain (MAT2012-37160), Consolider Ingenio 2010-MULTICAT, Generalitat Valenciana through the PROMETEO program, Universitat Politecnica de Valencia through PAID-06-11 (n.1952), the Swedish Research Council (VR), the Swedish Governmental Agency for Innovation Systems (VINNOVA), and the Goran Gustafsson Foundation. M. M. also acknowledges "Subprograma Ramon y Cajal" for Contract RYC-2011-08972. The TEM used in this study was purchased from a grant by the Knut and Alice Wallenberg Foundation. ; Martínez Franco, R.; Moliner Marin, M.; Yun, Y.; Sun, J.; Wan, W.; Zou, X.; Corma Canós, A. (2013). Synthesis of an extra-large molecular sieve using proton sponges as organic structure-directing agents. Proceedings of the National Academy of Sciences. 110(10):3749-3754. https://doi.org/10.1073/pnas.1220733110 ; S ; 3749 ; 3754 ; 110 ; 10

[EN] A rationalized combination of alkali cations and bulky dicationic organic structure directing agents (OSDAs) has allowed the synthesis of the Al-rich MTW zeolites with Si/Al ratios of similar to 12 and large pore accessibility. Al-27 MAS NMR spectroscopy indicates that most of the aluminum atoms are in tetrahedral coordination in framework positions, and in situ infrared pyridine adsorption/desorption spectroscopy reveals strong Bronsted acidity after cationic exchange for the Al-rich MTW. In addition, another MTW material with a Si/Al ratio of 30 has been synthesized under alkali-free conditions using a bulky dicationic molecule such as OSDA, the lowest Si/Al ratio being achieved for a MTW zeolite synthesized in the absence of alkali-cations in the synthesis media. The catalytic activity of these MTW materials has been tested for the n-decane cracking reaction, achieving higher catalytic activities and olefin yields than other related large pore zeolites. ; Financial support from the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), Consolider Ingenio 2010-Multicat and, MAT2012-37160 is acknowledged. ; Paris-Carrizo, CG.; Martín-García, N.; Martínez-Triguero, J.; Moliner Marin, M.; Corma Canós, A. (2016). Synthesis of Al-MTW with low Si/Al ratios by combining organic and inorganic structure directing agents. New Journal of Chemistry. 40(5):4140-4145. https://doi.org/10.1039/C5NJ01203A ; S ; 4140 ; 4145 ; 40 ; 5 ; LaPierre, R. B., Rohrman, A. C., Schlenker, J. L., Wood, J. D., Rubin, M. K., & Rohrbaugh, W. J. (1985). The framework topology of ZSM-12: A high-silica zeolite. Zeolites, 5(6), 346-348. doi:10.1016/0144-2449(85)90121-6 ; Gies, H., & Marker, B. (1992). The structure-controlling role of organic templates for the synthesis of porosils in the systems SiO2/template/H2O. Zeolites, 12(1), 42-49. doi:10.1016/0144-2449(92)90008-d ; Fyfe, C. A., Gies, H., Kokotailo, G. T., Marler, B., & Cox, D. E. (1990). Crystal structure of silica-ZSM-12 by the combined use of hgh-resolution ...

[EN] It has been possible to efficiently synthesize high-silica ERI and AFX zeolites with nano-sized primary crystallites (30-200 nm). This was achieved by using a dicationic and rigid organic structure directing agent (OSDA) that fits within the large cavities of these zeolites, and the use of FAU zeolites as initial Si and Al-sources. Cu- and Fe-based ERI and AFX materials were prepared following both post-synthetic cation exchange and direct synthesis methodologies, showing good activity for the selective catalytic reduction (SCR) of nitrogen oxide using ammonia. Accelerated hydrothermal ageing of the zeolites at high temperature (i.e. 750 degrees C) shows the necessity of removing the alkali cations remaining in the zeolites to obtain stable materials. Furthermore, the catalytic performance of the prepared Cu- and Fe-containing AFX catalyst, both before and after ageing treatment, approaches the catalytic activity of Cu- and Fe-CHA. (C) 2017 Elsevier B.V. All rights reserved. ; This work has been supported by Haldor Topsoe A/S, by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), and MAT2015-71261-R, by the European Union through ERC-AdG-2014-671093 (SynCatMatch) and by the Fundacion Ramon Areces through a research contract of the "Life and Materials Science" program. N. M. thanks MINECO for economical support through pre-doctoral fellowship (BES-2013-064347). The authors thank Isabel Millet for technical support. ; Martín-García, N.; Paris, C.; Vennestrom; Peter Nicolai Ravnborg; Thogersen, JR.; Corma Canós, A.; Moliner Marin, M. (2017). Cage-based small-pore catalysts for NH3-SCR prepared by combining bulky organic structure directing agents with modified zeolites as reagents. Applied Catalysis B Environmental. 217:125-136. https://doi.org/10.1016/j.apcatb.2017.05.082 ; S ; 125 ; 136 ; 217

This study develops the Burns and Stalker (1961) concept of organic structure, in operational terms, applying it to small work groups. A core dimension emerges, called "organicity, " which correlates strongly with the innovativeness of a group's task. The concept and the instruments for its measurement could find applications in studying the relation between individuals and their organizational work roles.

AbstractWhile much work in generative syntax has adopted bottom‐up syntactic derivation, a number of factors favor a top‐down approach. This article offers a new articulation of the top‐down Merge Right–Branch Right approach. In accord with the general Minimalist goals that computation should be carried out in small domains, that structure is based on binary pairings, and that grammatical mechanisms should, as far as possible, be limited to those that are logically necessary, three hypotheses are advanced: (i) that downward movement/copying of elements is driven by theta marking; (ii) that a [D] parameter operates across a range of syntactic constructions to direct displaced elements either through the syntactic structure or into a memory buffer to reach their points of selection/theta marking; and (iii) that the concept of the memory buffer previously proposed in the literature should be modified so that some but not all displaced elements enter it. The [D]‐parameter hypothesis offers a common basis for a variety of syntactic phenomena: short movement in expletive sentences, T‐to‐C movement in wh questions, the Comp–trace effect, and the anti‐Comp–trace effect seen in relative clauses.

The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) / ERC Grant Agreement n. 339478. Acronym LAYERENG-HYBMAT. | openaire: EC/FP7/339478/EU//LAYERENG-HYBMAT ; The possibility to deposit purely organic and hybrid inorganic–organic materials in a way parallel to the state-of-the-art gas-phase deposition method of inorganic thin films, i.e., atomic layer deposition (ALD), is currently experiencing a strongly growing interest. Like ALD in case of the inorganics, the emerging molecular layer deposition (MLD) technique for organic constituents can be employed to fabricate high-quality thin films and coatings with thickness and composition control on the molecular scale, even on complex three-dimensional structures. Moreover, by combining the two techniques, ALD and MLD, fundamentally new types of inorganic–organic hybrid materials can be produced. In this review article, we first describe the basic concepts regarding the MLD and ALD/MLD processes, followed by a comprehensive review of the various precursors and precursor pairs so far employed in these processes. Finally, we discuss the first proof-of-concept experiments in which the newly developed MLD and ALD/MLD processes are exploited to fabricate novel multilayer and nanostructure architectures by combining different inorganic, organic and hybrid material layers into on-demand designed mixtures, superlattices and nanolaminates, and employing new innovative nanotemplates or post-deposition treatments to, e.g., selectively decompose parts of the structure. Such layer-engineered and/or nanostructured hybrid materials with exciting combinations of functional properties hold great promise for high-end technological applications. ; Peer reviewed

This paper discusses the forensic investigation of a fatality-involved catastrophic structure collapse and the special challenges faced when tasked with directing such an effort. While this paper discusses the investigation's findings and the outcome of the event; this paper's primary focus is on the challenges faced directing a forensic investigation that requires coordinating with governmental oversight while also having to accommodate multiple parties' investigative teams. In particular the challenges discussed within this paper included maintaining on-site safety and operations while accommodating outside investigator's interests. In addition this paper discusses unique challenges that one may face such as what to do about unethical conduct of interested party's investigative teams, "off the record" sharing of information, and clandestinely transmitted evidence.

This project has received funding from: the European Union's Horizon 2020 research and innovation program under grant agreement No 685727; the Engineering & Physical Sciences Research Council (EPSRC) under awards EP/K005499/1 and EP/K039210/1; and the University of St Andrews School of Chemistry. ; Removal of coordinated water molecules from the porous Zn‐pyromellitate metal organic framework Zn5(OH)2(PMA)2(H2O)4 · x H2O (PMA = pyromellitic acid or 1,2,4,5‐benzene tetracarboxylic acid) should generate coordinatively unsaturated metal sites suitable for gas adsorption. However, reports of instability towards dehydration have restricted the study and utility of this MOF. Here we examine in more detail the nature of the structural transformation that occurs upon dehydration. This study reveals that a fully reversible crystalline‐crystalline transformation from a porous to a non‐porous homologue takes place, proceeding through a partially dehydrated intermediate. We show that doping the structure with Ni2+ ions at greater than 30 % prevents structural rearrangement, thereby maintaining porosity, and rendering the material effective for gas (nitric oxide) adsorption applications. These results indicate that doping can be an effective means to increase the utility of otherwise unserviceable structures. ; Publisher PDF ; Peer reviewed

This is the peer reviewed version of the following article: Chem. Eur. J. 2019, 25, 16390 16396 , which has been published in final form at https://doi.org/10.1002/chem.201904043. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] Expanding the previously known family of -onium (ammonium, phosphonium, and sulfonium) organic structure-directing agents (OSDAs) for the synthesis of zeolite MFI, a new member, the arsonium cation, is used for the first time. The new group of tetraalkylarsonium cations has allowed the synthesis of the zeolite ZSM-5 with several different chemical compositions, opening a route for the synthesis of zeolites with a new series of OSDA. Moreover, the use of As replacing N in the OSDA allows the introduction of probe atoms that facilitate the study of these molecules by powder X-ray diffraction (PXRD), solid-state nuclear magnetic resonance (MAS NMR), and X-ray absorption spectroscopy (XAS). Finally, the influence of trivalent elements such as B, Al, or Ga isomorphically replacing Si atoms in the framework structure and its interaction with the As species has been studied. The suitability of the tetraalkylarsonium cation for carrying out the crystallization of zeolites is demonstrated along with the benefit of the presence of As atoms in the occluded OSDA, which allows its advanced characterization as well as the study of its evolution during OSDA removal by thermal treatments. ; Program Severo Ochoa SEV-2016-0683 and Maria de Maeztu MDM-2015-0538 are gratefully acknowledged. S.S-F. thanks MEC for his Severo Ochoa Grant SPV-2013-067884, P.O.-B. and G.M.E. thank MEC for his Ramon y Cajal contracts (RYC-2014-16620 and RYC-2013-14386). The authors thank the financial support by the Spanish Government (RTI2018-096399-A-I00, RTI2018-101784-B-I00 and CTQ2017-89528-P) and the Generalitat Valeciana (PROMETEO/2017/066). The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. We ...

The main objective of this article is to present the differences in
the structures of certified organic farms in the European Union (EU) countries within 2005—2013, using dynamic and spatial approach. The method of vectors elimination was used in a study. The analysis showed that changes in the structure of organic farms in the EU countries were not always reflected in the structure of their areas. More significant changes occurred in the structure of farm number, in particular with regard to the countries which joined the European Union in 2004. In 2013 it was possible to distinguish five groups of EU countries that are similar to each other in terms of structure of number and six — in terms of the structure of area. In the majority of EU countries, organic farms covered the area over 10,0 ha.