524 research outputs found
Preface
No full textThe University of Pennsylvania Working Papers in Linguistics (PWPL) is an occasional series published by the Penn Graduate Linguistics Society. The series has included volumes of previously unpublished work, or work in progress, by linguists with an ongoing affiliation with the Department, as well as volumes of papers from NWAV and the Penn Linguistics Conference.
This volume contains selected papers accepted into the 45th Penn Linguistics Conference. Given the COVID-19 pandemic, PLC 45 took place virtually and all authors of oral presentations were invited to contribute a ten page paper to this volume. We thank our authors for their contribution and their patience and understanding in this editing process. We also thank Pik Yu May Chan, June Choe, Gwen Hildebrandt, Aini Li, Daoxin Li, Karen Li, Lefteris Paparounas, and Christine Soh for their help in editing.
Since Vol. 14.2, PWPL has been an internet-only publication. As of September 2014, the entire back catalog has been digitized and made available on ScholarlyCommons@Penn. Please continue citing PWPL papers or issues as you would a print journal article, though you may also provide the URL of the manuscript. An example is below:
Lee, Soo-Hwan, and Yining Nie. 2022. In University of Pennsylvania Working Papers in Linguistics 28.1, ed. Johanna Benz and Yiran Chen, 86-95. Available at: http://repository.upenn.edu/pwpl/vol28/iss1/11.
Publication in the University of Pennsylvania Working Papers in Linguistics (PWPL) does not preclude submission of papers elsewhere; copyright is retained by the author(s) of individual papers.
The PWPL editors can be contacted at: U. Penn Working Papers in Linguistics, Department of Linguistics, 3401-C Walnut Street, Suite 300, C Wing, Philadelphia, PA 19104-6228 and [email protected].
Johanna Benz and Yiran Chen, Issue Editor
Synthesis and characterization of TiL2 complexes with tridentate (ONO) (S)-NOBIN Schiff-base ligands
No full textTridentate (ONO) C[subscript 1]-symmetric Schiff base ligands were synthesized by the condensation of (S)-2-amino-2'-hydroxy-1,1'-binaphthyalene with 4-hydroxy-3-phenanthrenecarboxaldehyde or 1-hydroxybenz[a]anthracene-2-carboxaldehyde. C[subscript 2]-symmetric titanium(IV) Schiff base complexes, TiL[subscript 2], were synthesized and characterized with these ligands. The complex with the benz[a]anthryl unit crystallizes in a facial coordination mode, OC-6-1'3'-C, whereas complex with phenanthryl unit crystallizes in a meridional mode, OC-6-22'-A. A comparison between the complexes and the ligands were done in solution using circular dichroism spectroscopy. Preliminary catalytic studies showed that these complexes can catalyze asymmetric carbonyl-ene addition reactions of 2-methoxypropene with aromatic aldehydes with moderate selectivity. The ligands and complexes were characterized by NMR, HRMS, single crystal X-ray diffraction and CD spectroscopy
Observations on the synthesis of photochromic naphthopyrans
No full text1-Naphthol reacts with 1,1-diarylprop-2-yn-1-ols 5a,b, under alumina catalysis, by two pathways to give the photochromic naphtho[1,2-b]pyrans 6a,b, together with the propenylid-enenaphthalenones 7a,b, representatives of a new class of merocyanine dyes. With 2-methyl-1-naphthol, formation of the photochrome is suppressed; the only products are merocyanines 7c,d. The cyclocondensation of 2-naphthol with 5a,b proceeds much more efficiently, to give the naphtho[2, 1 b]pyrans 14a,b. Pyran formation is not suppressed from either 1-bromo- or 1- (4-methoxyphenyl)-2-naphthol; reaction with 5a,b merely results in expulsion of the C-1 substituent. An alternative pathway supervenes in the reaction of 1-methyl-2-naphthol with 5a to give the benz[e]indanone 17, the constitution of which was determined by X-ray crystallography. Reaction of the 1,3,3-triarylpropynols 19a,b with 1-naphthol affords the naphthopyrans 20 together with merocyanines 21, whilst the isomeric pyrans 23 are efficiently produced from 2-naphthol. The configuration of merocyanines 7a and 21 a was unequivocally established by X-ray crystallography
Cross-Coupling of α-carbonyl sulfoxonium ylides with C-H bonds
No full textThe functionalization of carbon-hydrogen bonds in non-nucleophilic substrates using α-carbonyl sulfoxonium ylides has not been so far investigated, despite the potential safety advantages that those reagents would provide over diazo compounds or their in situ precursors. We describe the cross-coupling reactions of sulfoxonium ylides with C(sp2)-H bond of arenes and heteroarenes in the presence of a rhodium catalyst. The reaction proceeds by a succession of C-H activation, migratory insertion of the ylide into the carbon-metal bond and protonation, the last step being turnover-limiting. The method is applied to the synthesis of benz[c]acridines when allied to an iridium-catalyzed dehydrative cyclization
Gerold Ambrosius/Christian Henrich-Franke, Integration von Infrastrukturen in Europa im historischen Vergleich, Band 1: Synopse (Integration of European Infrastructure in Historical Perspective: Volume 1, Synopsis); Berenice Ahr, Integration von Infrastrukturen in Europa im historischen Vergleich, Band 2: Telekommunikation (Telefonie) (Integration of European Infrastructure in Historical Perspective: Volume 2, Telephone); Andreas Benz, Integration von Infrastrukturen in Europa im historischen Vergleich, Band 3: Post (Integration of European Infrastructure in Historical Perspective: Volume 3, Postal Service)
No full textKopper C. Gerold Ambrosius/Christian Henrich-Franke, Integration von Infrastrukturen in Europa im historischen Vergleich, Band 1: Synopse (Integration of European Infrastructure in Historical Perspective: Volume 1, Synopsis); Berenice Ahr, Integration von Infrastrukturen in Europa im historischen Vergleich, Band 2: Telekommunikation (Telefonie) (Integration of European Infrastructure in Historical Perspective: Volume 2, Telephone); Andreas Benz, Integration von Infrastrukturen in Europa im historischen Vergleich, Band 3: Post (Integration of European Infrastructure in Historical Perspective: Volume 3, Postal Service). JOURNAL OF TRANSPORT HISTORY. 2016;37(1):119-120
Radio sources in the Chandra Galactic Bulge Survey
No full textWe discuss radio sources in the Chandra Galactic Bulge Survey region. By cross-matching the X-ray sources in this field with the NRAO VLA Sky Survey archival data, we find 12 candidate matches. We present a classification scheme for radio/X-ray matches in surveys taken in or near the Galactic plane, taking into account other multiwavelength data. We show that none of the matches found here is likely to be due to coronal activity from normal stars because the radio to X-ray flux ratios are systematically too high. We show that one of the source could be a radio pulsar, and that one could be a planetary nebula, but that the bulk of the sources are likely to be background active galactic nuclei (AGN), with many confirmed through a variety of approaches. Several of the AGN are bright enough in the near-infrared (and presumably in the optical) to use as probes of the interstellar medium in the inner Galaxy
A practice based learning environment for engineering students: Acquiring competencies for working on advanced manufacturing engineering
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.In this thesis the author describes the design and operation of a learning environment aimed at imparting technical, technological and managerial knowledge, developing understanding of the underlying issues and enhancing team work skills for an advanced technology future. He offers an analysis of learning, education and training and compares group work with individual tasks, presents a major case study and illustrates the features which distinguish the approach from role play, simulation and experiential learning. When staff at Brunel University were faced with the problem of teaching Computer Integrated Manufacturing (CIM) to engineering students on thin sandwich type undergraduate degree programmes the writer suggested the use of an approach he would later describe as 'practice based learning' or 'real life simulation'. The fourth year course in CIM is designed as a double option for the complementary undergraduate courses, Brunel Manufacturing Engineering (BME) and Special Engineering Programmes (SEP). It is an extension of the Manufacturing Design and Practice course in years one to three of the BME course and of the Design strand on SEP, both of which restrict students' work to the use of individual machine tools and stand alone computing facilities. A wide range of teaching methods is used on the CIM course, including lectures by course staff, presentations by experts and, as the major element, a large group project involving all the students on the course, organised in a management matrix, coordinated by the students and supported by the staff acting as experts. The students also undertake assignment work alongside the technical tasks, to focus their thinking and to improve written communication skills. While the course described cannot replace more than a small proportion of the more conventional lecture, laboratory and tutorial teaching on an engineering programme, it provides a setting where students can experiment and learn about their own strengths and weaknesses in a realistic situation and in the context of teamwork. It also offers a space where they can make quite serious mistakes without direct consequences to their careers. The experience of seven years leads the author to believe that advanced manufacturing technologies and the associated management techniques should be taught in a project based environment with clear and real targets and realistic constraints, offering students challenges to which they can only rise through close and creative team work. The management of task execution must be left largely in the students' own hands. A high level of "consultant" type support is essential though, allied to an assessment scheme which promises and ensures fair treatment of the individual. The different parts of the thesis will be relevant to readers depending on their interest and background. Chapter 1 sets the scene and outlines the approach taken. Following this broad outline of the scope of the dissertation the author places Computer Integrated Manufacturing in a wider context in chapter 2, by providing an introduction to the underlying issues of computer integration and human factors. He puts forward a case for new approaches to the education and training of engineers and managers who will be working in Computer Integrated Manufacturing and Advanced Manufacturing Environments in general. Chapter 3 is devoted to the management of projects while chapter 4 is used to question the role of the engineer. Chapters 5 and 6 provide an introduction to theories of knowledge, teaching, learning and motivation. Chapters 7 and 8 are devoted to particular aspects of engineering education, while chapter 9 reviews the approach used at Brunel University. The topical issues of competence and its relevance to engineering education is discussed in chapter 10, leading into chapters 11 and 12 which deal with aspects of the CIM course. Chapters 13 and 14 are devoted to case-studies and particular tools. The key question of assessment of a practice oriented and team based course is addressed in chapter 15, followed by an evaluation of the CIM process and its application to engineering education of a full time nature which is included in chapters 17 and 18.Funding was obtained from The General Electric Company Prize 1993: Manufacturing Systems Engineering
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