1,917 research outputs found
Self-Destructing Polymers: Creating Thermally Sensitive End-Caps
No full textSelf-Destructing Polymers: Creating Thermally Sensitive End-Caps Trant Team Rose Anne Fayoumi A broad and booming field of research and innovation, polymer science blends chemistry, physics and engineering and breeds countless modern materials and devices. Likewise, the degradation of these polymers is a field of interest due to the consideration of environmental, medical and economical factors. Nowadays, conventional biodegradable polymers degrade, but require an enzyme to cleave every single connection between monomers before complete disintegration. Numerous stimulus events are thus necessary, promoting inefficient and slow environmental degradation that can take weeks to years. To address this, the Trant Team is developing a new class of polymers that self-destruct on-demand using organic chemistry. Only one stimulus event, removing the end, destabilizes the polymer, which leads it to quickly disintegrate in only a few hours. These self-immolative polymers hence need ends with a functionality that can be triggered, as the push required to initiate the domino-like effect. In our case, this push is an elevated temperature that causes the end-cap to destabilize and degrade. Elevated temperatures can be induced via intersecting laser beams or magnetic fields to create heat in desired areas. In addition, the optimal temperature for the degradation of each end-cap will be determined through kinetic studies. Ultimately, specific reversible chemical reactions will be exploited to create such thermally-sensitive end-caps, allowing on-demand degradation of the polymer's constituents by elevated temperatures. Accordingly, this innovation could potentially lead to endless possibilities and applications, including therapeutic, pharmaceutical, and biomedical applications. At this stage, however, it is too early to report findings as research and data collection are currently in progress. In spite of this, the presentation will review our preliminary results with this technology as well as shed light on its various potential applications
Self-Destructing Polymers: Creating Thermally Sensitive End-Caps
No full textSelf-Destructing Polymers: Creating Thermally Sensitive End-Caps Trant Team – Rose Anne Fayoumi A broad and booming field of research and innovation, polymer science blends chemistry, physics and engineering and breeds countless modern materials and devices. Likewise, the degradation of these polymers is a field of interest due to the consideration of environmental, medical and economical factors. Nowadays, conventional biodegradable polymers degrade, but require an enzyme to cleave every single connection between monomers before complete disintegration. Numerous stimulus events are thus necessary, promoting inefficient and slow environmental degradation that can take weeks to years. To address this, the Trant Team is developing a new class of polymers that self-destruct “on-demand� using organic chemistry. Only one stimulus event, removing the end, destabilizes the polymer, which leads it to quickly disintegrate in only a few hours. These self-immolative polymers hence need ends with a functionality that can be triggered, as the “push� required to initiate the domino-like effect. In our case, this push is an elevated temperature that causes the end-cap to destabilize and degrade. Elevated temperatures can be induced via intersecting laser beams or magnetic fields to create heat in desired areas. In addition, the optimal temperature for the degradation of each end-cap will be determined through kinetic studies. Ultimately, specific reversible chemical reactions will be exploited to create such thermally-sensitive end-caps, allowing “on-demand� degradation of the polymer’s constituents by elevated temperatures. Accordingly, this innovation could potentially lead to endless possibilities and applications, including therapeutic, pharmaceutical, and biomedical applications. At this stage, however, it is too early to report findings as research and data collection are currently in progress. In spite of this, the presentation will review our preliminary results with this technology as well as shed light on its various potential applications
t-Butylamine as a "new" agent for mild and selective deacetylation
No full textSustainable IndustryThe selective removal of acetates in the presence of longer chain esters remains a significant challenge in organic chemistry, specifically carbohydrate chemistry. In a recent synthetic project, the Trant group had to remove a series of acetates without cleaving other esters, and all listed chemical methods in Green and Wutz either failed to provide selectivity or degraded the complex carbohydrate. To address this challenge, we had turned to methoxyacetates as an alternative protecting group. Standard conditions for their cleavage involve the use of tert-butylamine, although the precise mechanism of action remains unclear. We happily found that these mild, selective conditions are also appropriate for the acetate group. In this presentation we discuss the potential application of this reagent for the selective hydrolysis of acetates in complex protected carbohydrates, as well our explorations into the chemoselectivity, kinetic profile, and scope and limits of this reaction
John F. Kucia interview
No full textFor 34 years Dr. John F. Kucia served Xavier University, first as the Director of Alumni Relations from 1984 to 1986, then as Assistant to the President from 1986 to 1990, and finally as Administrative Vice President from 1990 to 2018. During these years, he worked closely with five different Xavier presidents and played a key role in transforming Xavier’s campus. In addition, Kucia oversaw Xavier’s intercollegiate athletic program through a period of growth. In this interview, he discusses the five Xavier presidents with whom he worked, identifying the challenges and achievements of each. He talks about the land acquisitions, building projects, and facilities development that occurred during his tenure, including the Cintas Center, the University Station and the Health United Building. He also discusses the success of Xavier’s athletic programs and the vital role that sports play in university life. Kucia earned a doctorate in higher education management from the University of Pennsylvania and is co-author of the book Leadership in Balance: New Habits of the Mind, which he talks about in the interview. He currently serves as Xavier’s Vice President Emeritus
Dr. Adelaide Fries
No full textAdelaide Lisetta Fries (born November 12, 1871, died November 29, 1949), was the daughter of John William and Agnes de Schweinitz Fries. Dr. Fries was noted historian and author. She is best known for her translations of the Records of the Moravians in North Carolina and writing the historical novel The Road to Salem. In 1911, Dr. Fries was appointed archivist of the Moravian Church, Southern Province, in Winston-Salem and served in that position for nearly forty years
Everybody's happy when the moon shines
No full textGift of Dr. Mary Jane Esplen.Piano vocal [instrumentation]F major [key]Moderato [tempo]Popular song [form/genre]Moonface, couples silhouetted, photograph: Julia Frark [illustration]De Takacs [engraver]Publisher's advertisement on front inside cover & back cover [note
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A study of John Clare in his historical and political context
No full textAs the title indicates, the basis of the thesis is to set John Clare’s life and work within the context of the social and political history of his time. It is a study that is long overdue. The manner in which topical and political matters were mediated to him and were reflected in his work are analysed. His introduction to the literary and social worlds of Stamford and London is evaluated, and the advantages and disadvantages of patronage assessed. The active and complex political culture of Stamford has been taken into account as this may have affected his later political statements and a growing awareness of his audience. His antagonism to enclosure and the social changes that it engendered are considered. Three major questions that arise from this are addressed. The two local newspapers that Clare is known to have read are used throughout. His correspondence with friends, colleagues and casual correspondents has provided valuable insights as have his poetry and prose writings. Research in the Northamptonshire Record Office has revealed important new information in the form of one book of Enclosure Commissioners’ Minutes dated 1809-14, the first five years of the enclosure of Helpstone, Clare’s native village
Program: 1988 Featured Lecture, The Journey of Personal Faith
No full textProgram for the Eighth Annual Thomas F. Staley (Frank Pack) Distinguished Christian Lecture Program with featured lecturer, Dr. John Killinger the Senior Minister of the First Congregational Church of Los Angeles and theological author
Program: 1984 Featured Lecture, The Hand on Your Shoulder
No full textProgram for the Fourth Annual Thomas F. Staley (Frank Pack) Distinguished Christian Lecture Program with featured lecturer Dr. John White, Author, Lecturer, and retired Professor from the University of Manitoba
John Gay's the beggar's opera: early eighteenth-century responses in the arts to cultural, sociological and political issues in London life
No full textDiffering responses in art media to these contemporary issues of London life are explored, taking John Gay's the Beggar's Opera as the focal point for discussion. Initially, a general survey is made of Gay's role as cultural, social and moral critic. Comparison with George Frederick Handel's Floridante allows Gay's work to be placed in the context of operatic responses to contemporary society, highlighting usage both of overt portrayal and indirect satire. Gay's approach to political issues is examined alongside that of Dean Swift's Gulliver's Travels enabling an estimation to be made of the effectiveness of these art media as tools of political propaganda. Similarly, responses in the field of painting are discussed in the light of representative works of James Thornhill and William Hogarth's A Harlot's Progress and A Rake's Progress. In considering all these responses it is noted that art can be interpreted at differing levels, from the sophisticated to the naive. All these art media are then placed in the context of artistic philosophy of the period, thus facilitating an objective assessment of the parallels and differences of art's responses to contemporary issues. Taking into account inherent limitations in the media, to conclude our study, Hogarth's The Beggar's Opera Scenes are compared and contrasted with Gay's prototype. The thesis highlights the trend towards realism in the arts during this period. Nevertheless, we are left with the conundrum that art, 'per se', can only 'mirror' life. It does not necessarily solve its problems. Thesis submitted in fulfilment of the requirements for the degree of Master of Arts in Music. University of Durham Department of Music 198
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