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2021 ◽  
Author(s):  
◽  
Greg Taylor

<p>This thesis examines two sections of William Wordsworth’s autobiographical poem, The Prelude: Book 3, “Residence at Cambridge,” and Book 7, “Residence in London.” Books 3 and 7 are often read as interruptions in the poem’s narrative of psychological and artistic maturation. “Cambridge” and “London” are often read as impediments to the development of Wordsworth’s imagination, a development which is traditionally associated with transcendental epiphany in nature. This thesis offers a re-reading of the Cambridge and London books, emphasizing their affirmative role in the organic structure of the poem, and suggesting that these spaces allow Wordsworth to reflect positively on his imaginative development.  Chapter 1 considers the issues involved in a literature review. Chapter 2 looks at the representation of Wordsworth’s adjustment to Cambridge. Though the poet considers his imagination to have been dormant during his first year at university, Book 3 depicts a phase in which the mind is opening toward outside influences. In the sheltered groves and level fenland of Cambridge, Wordsworth finds an environment both protective and sufficiently strange to stimulate his sense of inner power. Chapter 3 is concerned with Wordsworth’s changing attitudes toward London. The poet was composing Book 7 over a period of time during which he made multiple trips to the city. While it is ostensibly the record of his very first residence in London, Book 7 has a palimpsestic quality, layering together different encounters with the city and exhibiting an increasingly affirmative vision of urban life. In particular, this chapter traces the influence of Charles Lamb on Wordsworth’s thinking about London. Chapter 4 considers the centrality of the body and the sense of touch in Wordsworth’s response to London. Touch in Book 7 is both a source of anxiety and the vehicle for Wordsworth’s understanding of the city, its influence on him and its significance for a poetics of belonging.</p>


2021 ◽  
Author(s):  
◽  
Greg Taylor

<p>This thesis examines two sections of William Wordsworth’s autobiographical poem, The Prelude: Book 3, “Residence at Cambridge,” and Book 7, “Residence in London.” Books 3 and 7 are often read as interruptions in the poem’s narrative of psychological and artistic maturation. “Cambridge” and “London” are often read as impediments to the development of Wordsworth’s imagination, a development which is traditionally associated with transcendental epiphany in nature. This thesis offers a re-reading of the Cambridge and London books, emphasizing their affirmative role in the organic structure of the poem, and suggesting that these spaces allow Wordsworth to reflect positively on his imaginative development.  Chapter 1 considers the issues involved in a literature review. Chapter 2 looks at the representation of Wordsworth’s adjustment to Cambridge. Though the poet considers his imagination to have been dormant during his first year at university, Book 3 depicts a phase in which the mind is opening toward outside influences. In the sheltered groves and level fenland of Cambridge, Wordsworth finds an environment both protective and sufficiently strange to stimulate his sense of inner power. Chapter 3 is concerned with Wordsworth’s changing attitudes toward London. The poet was composing Book 7 over a period of time during which he made multiple trips to the city. While it is ostensibly the record of his very first residence in London, Book 7 has a palimpsestic quality, layering together different encounters with the city and exhibiting an increasingly affirmative vision of urban life. In particular, this chapter traces the influence of Charles Lamb on Wordsworth’s thinking about London. Chapter 4 considers the centrality of the body and the sense of touch in Wordsworth’s response to London. Touch in Book 7 is both a source of anxiety and the vehicle for Wordsworth’s understanding of the city, its influence on him and its significance for a poetics of belonging.</p>


2021 ◽  
Author(s):  
Daniel Schwalbe-Koda ◽  
Avelino Corma ◽  
Yuriy Román-Leshkov ◽  
Manuel Moliner ◽  
Rafael Gómez-Bombarelli

Zeolites are inorganic materials with wide industrial applications due to their topological diversity. Tailoring confinement effects in zeolite pores, for instance by crystallizing intergrown frameworks, can improve their catalytic and transport properties, but controlling zeolite crystallization often relies on heuristics. In this work, we use computational simulations and data mining to design organic structure-directing agents (OSDAs) to favor the synthesis of intergrown zeolites. First, we propose design principles to identify OSDAs which are selective towards both end members of the disordered structure. Then, we mine a database of hundreds of thousands of zeolite-OSDA pairs and downselect OSDA candidates to synthesize known intergrowth zeolites such as CHA/AFX, MTT/TON, and BEC/ISV. The computationally designed OSDAs balance phase competition metrics and shape selectivity towards the frameworks, thus bypassing expensive dual-OSDA approaches typically used in the synthesis of intergrowths. Finally, we propose potential OSDAs to obtain hypothesized disordered frameworks such as AEI/SAV. This work may accelerate zeolite discovery through data-driven synthesis optimization and design.


2021 ◽  
Vol 11 (15) ◽  
pp. 6850
Author(s):  
Joaquin Martinez-Ortigosa ◽  
Jorge Simancas ◽  
Jose A. Vidal-Moya ◽  
Fernando Rey ◽  
Susana Valencia ◽  
...  

The nature of organic structure directing agents (OSDAs) is of paramount importance in the final properties of zeolites, particularly the framework and porosity. Recently, the use of P-containing OSDAs has been employed for new zeolites, but there is little discussion compared to their analogues N-OSDAs. The main objective of this work is the characterization of pure silica MFI zeolite (silicalite-1) prepared by the dual-template route with tetrapropylammonium (TPA), tetrapropylphosphonium (TPP) cations, and mixtures thereof aiming to understand by advanced NMR methods how the nature of the organic influences the physico-chemical properties of the zeolite. Silicalite-1 has been successfully synthesized using the dual-template procedure with TPA and TPP molecules. Both OSDAs are incorporated into the zeolite without any specific preference, differently to that observed before for the TEA/TEP system, and homogenously mixed inside of the zeolite voids. The presence of TPP leads to the incorporation of less F, raising the concentration of Q3-defective sites in the silicalite-1 zeolites. Detailed NMR results indicate that those structural defects are close to the –CH3 group of the entrapped OSDAs in the zeolite and these defects consist of at least two silanol groups stabilizing the Si-O- species, which is responsible for the charge balancing.


Science ◽  
2021 ◽  
Vol 373 (6550) ◽  
pp. 104-107 ◽  
Author(s):  
Hwajun Lee ◽  
Jiho Shin ◽  
Kyounghwan Lee ◽  
Hyun June Choi ◽  
Alvaro Mayoral ◽  
...  

UCSB-6 (framework type SBS) and UCSB-10 (SBT), two three-dimensional phosphate-based molecular sieves with supercages accessible through 12-ring (circumscribed by 12 tetrahedral atoms) windows, are structurally similar to the hexagonal and cubic polytypes of faujasite or zeolite Y, an industrially relevant catalyst, but the cage structures are substantially different. Nonetheless, their inherent thermal instability has precluded any catalytic application so far. By using multiple inorganic cation and charge density mismatch approaches, we synthesized PST-32 and PST-2, a thermally stable aluminosilicate version of UCSB-10 and the hypothetical SBS/SBT intergrowth family member, respectively. This study suggests that many hypothetical cage-based zeolite structures with multidimensional channel systems can be synthesized as compositionally robust forms by systematically exploring the synergy effect of inorganic and organic structure–directing agents.


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