991 research outputs found
Other works of Serigne Mor Kayre
No full textThe entire manuscript is available for download below as a single PDF file. Because of the large size of this manuscript, it is also available in two PDF files. In addition, each page is available as a separate, larger, JPG file. If higher-resolution JP2 files are needed (WARNING: files average 11-14MB in size), please contact [email protected].
Fieldwork Team: Dr. Fallou Ngom (PI), Cheikh Tidiane Fall (Co-applicant), Ablaye Diakite (Researcher), Birane Gassama (Researcher).
Technical Team: Roger Brisson (Head of Metadata Services, BU Libraries), Vika Zafrin (Institutional Repository Librarian, BU Libraries), Jack Ammerman (Associate University Librarian for Digital Initiatives and Open Access, BU Libraries), and Dr. Peter Quella.
This collection of Wolofal (Wolof Ajami) materials is copied as part of the EAP 334 Project (Digital Preservation of Wolof Ajami manuscripts of Senegal) led by Dr. Fallou Ngom in collaboration with WARA/WARC and Boston University Library. The project is funded by the British Library/Arcadia Endangered Archives.
Access Condition and Copyright: The materials are subject to copyright. Access is for research and educational purposes only. Materials are not to be reproduced without written permission.
Citation: Materials in this web edition may be cited as: Ngom, Fallou. 2011. African Ajami Library: EAP 334. Digital Preservation of Wolof Ajami Manuscripts of Senegal. Boston: Boston University Library: http://dcommon.bu.edu
For Inquires: Please, contact Professor Fallou Ngom ([email protected])The material consists of Wolof Ajami poems (Wolofal) by Serigne Mor Kayre (1869-1951). The material is written in black ink. There are also insertions of Arabic words and phrases, including in openings and closings. The collection contains discussions on the qualities of Prophet Muhammad, the qualities of a genuine Murid disciple, discussions on the Tijaniyya and Qadiriyya Sufi orders, as well as recommendations for Murid disciples and their leaders.
Serigne Mor Kayre (1869-1951) was one of the earliest Murid Ajami scholars and poets. He was a member of the Tijaniyya Sufi order before becoming a Murid disciple when he met Ahmadou Bamba. His work includes eulogies of some Murid leaders, praises of Prophet Muhammad and Ahmadou Bamba's teachings, and devotional Sufi poetry, among others. His work has helped to disseminate Bamba's teachings and the Murid work ethics among the Wolof masses. His poetry has generated some Sufi songs, some of which are available on the internet today.
Serigne Mor Kayre is the author and scribe of the 2 original pages, but the copyist of the 74 photocopied pages of the work is unknown.
Mame Mor Kayre, the owner of the materials, is named after his grandfather Serigne Mor Kayre (1869-1951), the author the materials. He was born in 1978 in Khombole in the region of Thies. Mame Mor Kayre is currently a quranic teacher in Touba-Darou Khoudoss, Senegal. He received the materials from his older half-brother called Khadim Kayre, a quranic teacher and writer living in Dakar, Senegal.
Digitized on 27 November 2011.
The 74 handwritten pages copied are readable, but the 2 original pages are difficult to read due to their age.British Library (EAP 334
Ultrafast charge carrier and exciton dynamics in an excitonic insulator probed by time-resolved photoemission spectroscopy
No full textAn excitonic insulator phase is expected to arise from the spontaneous formation of electron-hole pairs (excitons) in semiconductors where the exciton binding energy exceeds the size of the electronic band gap. At low temperature, these ground state excitons stabilize a new phase by condensing at lower energy than the electrons at the valence band top, thereby widening the electronic band gap. The envisioned opportunity to explore many-boson phenomena in an exci-tonic insulator system is triggering a very active debate on how ground state excitons can be experimentally evidenced. Here, we employ a nonequilibrium approach to spectrally disentangle the photoinduced dynamics of an exciton condensate from the entwined signature of the valence band electrons. By means of time-and angle-resolved photoemission spectroscopy of the occupied and unoccupied electronic states, we follow the complementary dynamics of conduction and valence band electrons in the photoexcited low-temperature phase of Ta2NiSe5, the hitherto most promising single-crystal candidate to undergo a semiconductor-to-excitonic-insulator phase transition. The photoexcited conduction electrons are found to relax within less than 1 ps. Their relaxation time is inversely proportional to their excess energy, a dependence that we attribute to the reduced screening of Coulomb interaction and the low dimensionality of Ta2NiSe5. Long after (> 10 ps) the conduction band has emptied, the photoemission intensity below the Fermi energy has not fully recovered the equilibrium value. Notably, this seeming carrier imbalance cannot be rationalized simply by the relaxation of photoexcited electrons and holes across the semi-conductor band gap. Rather, a rate equation model involving different photoemission cross -sections of the valence electrons and the condensed excitons is able to reproduce the delayed recovery of the photoemission intensity below the Fermi energy. The model shows that electron quantum tunnelling between the exciton condensate and the valence band top is enabled by an extremely small activation energy of 4 x 10-6 eV and explains the retarded recovery of the exciton condensate. Our findings not only determine the energy gain of ground state exciton formation with exceptional energy resolution, but also demonstrate the use of time-resolved photoemission to unveil the re-formation dynamics of an exciton condensate with femtosecond time resolution
Some of the works of Serigne Mor Kayre
No full textDate created: unknown. The entire manuscript is available for download below as a single PDF file. Each page is also available as a separate, larger, JPG file. If higher-resolution JP2 files are needed (WARNING: files average 11-14MB in size), please contact [email protected].
Fieldwork Team: Dr. Fallou Ngom (PI), Cheikh Tidiane Fall (Co-applicant), Ablaye Diakite (Researcher), Birane Gassama (Researcher)
Technical Team: Roger Brisson (Head of Metadata Services, BU Libraries), Vika Zafrin (Institutional Repository Librarian, BU Libraries), Jack Ammerman (Associate University Librarian for Digital Initiatives and Open Access, BU Libraries), and Dr. Peter Quella.
This collection of Wolofal (Wolof Ajami) materials is copied as part of the EAP 334 Project (Digital Preservation of Wolof Ajami manuscripts of Senegal) led by Dr. Fallou Ngom in collaboration with WARA/WARC and Boston University Library. The project is funded by the British Library/Arcadia Endangered Archives.
Access Condition and Copyright: The materials are subject to copyright. Access is for research and educational purposes only. Materials are not to be reproduced without written permission.
Citation: Materials in this web edition may be cited as: Ngom, Fallou. 2011. African Ajami Library: EAP 334. Digital Preservation of Wolof Ajami Manuscripts of Senegal. Boston: Boston University Library: http://open.bu.edu
For Inquires: Please, contact Professor Fallou Ngom ([email protected])These materials are a collection of Wolof Ajami (Wolofal) poems by Serigne Mor Kayre (1869-1951). Red and black ink are used in the first set of original manuscripts. The red ink is used to highlight key words and phrases. There are also insertions of Arabic words and phrases, including in opening and closing formulae. The collection contains a hagiography of Prophet Muhammad, his family members and his miracles; a discussion on the battle of Badr; a song dedicated to Cheikh Ahmadou Bamba; a discussion on the norms for the construction of a mosque; a tribute to Serigne Modou Moustapha Mbacke (the first khalifa of the Muridiyya order); a tribute to Serigne Moussa Ka (his fellow Murid disciple and poet); and a table of contents summarizing the author's key pieces of work, among others.
Materials consist of 17 pages of the original manuscript and 53 photocopies of some of Serigne Mor Kayre's work copied by hand. Serigne Mor Kayre is the author and scribe of the 17 original pages, but the copyist of the 53 photocopied pages of his work is unknown.
Digitized on 24 July 2011.
Due to the age and poor quality of the photocopy of some pages, some lines are a hard to read. Many of Mor Kayre's original works are lost.This collection of Wolofal (Wolof Ajami) materials is copied as part of the EAP 334 Project (Digital Preservation of Wolof Ajami manuscripts of Senegal) led by Dr. Fallou Ngom in collaboration with WARA/WARC and Boston University Library. The project is funded by the British Library/Arcadia Endangered Archives
Letter from Ois�n Ua Mor�in to Fr. O'Callaghan
No full textHolograph letter from Ois�n Ua Mor�in of The New Leader, 205 New Brunswick Street, Dublin, to Fr. O'Callaghan [Rome]. The author of the article is happy if his name is disclosed to Dr. O'Hagan and will be glad to be in communication with him; he is Fr. E. Carroll in Crayford, Kent
Unveiling the exciton formation in time, energy and momentum domain in layered van der Waals semiconductors
No full textResolving the early-stage dynamics of exciton formation following non-resonant photoexcitation in time, energy, and momentum is quite challenging due to their inherently fast timescales and the proximity of the excitonic state to the bottom of the conduction band. In this study, by combining time- and angle-resolved photoemission spectroscopy with ab initio numerical simulations, we capture the timing of the early-stage exciton dynamics in energy and momentum, starting from the photoexcited population in the conduction band, progressing through the formation of free excitons, and ultimately leading to their trapping in lattice deformations. The chosen material is bismuth tri-iodide (BiI
), a layered semiconductor with a rich landscape of excitons in the electronic structure both in bulk and in monolayer form. The obtained results, providing a full characterization of the exciton formation, elucidate the early stages of the physical phenomena underlying the operation of the ultrafast semiconductor device
Inhibition of the photoinduced structural phase transition in the excitonic insulator Ta2NiSe5
No full textFemtosecond time-resolved midinfrared reflectivity is used to investigate the electron and phonon dynamics occurring at the direct band gap of the excitonic insulator Ta2NiSe5 below the critical temperature of its structural phase transition. We find that the phonon dynamics show a strong coupling to the excitation of free carriers at the Γ point of the Brillouin zone. The optical response saturates at a critical excitation fluence FC=0.30±0.08 mJ/cm2 due to optical absorption saturation. This limits the optical excitation density in Ta2NiSe5 so that the system cannot be pumped sufficiently strongly to undergo the structural change to the high-temperature phase. We thereby demonstrate that Ta2NiSe5 exhibits a blocking mechanism when pumped in the near-infrared regime, preventing a nonthermal structural phase transition
and H‐MOR Catalysts
No full textA combined catalyst comprising TiO2-supported Re (Re(1)/TiO2; Re=1 wt\%) and H-MOR (SiO2/Al2O3=90) was found to promote the methylation of benzene using CO2 and H2. This catalytic system exhibited high performance with regard to the synthesis of methylated benzenes and gave high yields of total methylated products (up to 52 \% benzene-based yield and 42 \% CO2-based yield) under the reaction conditions employed in this study (pCO2=1 MPa; pH2=5 MPa; T=250 °C; t=20 h) in a batch reactor. Catalyst screening demonstrated that a combination of Re(1)/TiO2 and H-MOR (SiO2/Al2O3=90) exhibited superior performance compared to other combinations of supported metal catalysts and zeolites in terms of both yield and selectivity for methylated benzenes
Mott resistive switching initiated by topological defects
No full textResistive switching is the fundamental process that triggers the sudden
change of the electrical properties in solid-state devices under the action of
intense electric fields. Despite its relevance for information processing,
ultrafast electronics, neuromorphic devices, resistive memories and
brain-inspired computation, the nature of the local stochastic fluctuations
that drive the formation of metallic nuclei out of the insulating state has
remained hidden. Here, using operando X-ray nano-imaging, we have captured the
early-stages of resistive switching in a V2O3-based device under working
conditions. V2O3 is a paradigmatic Mott material, which undergoes a first-order
metal-to-insulator transition coupled to a lattice transformation that breaks
the threefold rotational symmetry of the rhombohedral metal phase. We reveal a
new class of volatile electronic switching triggered by nanoscale topological
defects of the lattice order parameter of the insulating phase. Our results
pave the way to the use of strain engineering approaches to manipulate
topological defects and achieve the full control of the electronic Mott
switching. The concept of topology-driven reversible electronic transition is
of interest for a broad class of quantum materials, comprising transition metal
oxides, chalcogenides and kagome metals, that exhibit first-order electronic
transitions coupled to a symmetry-breaking order
Understanding Gender Equity in Author Order Assignment
No full textWomen remain underrepresented in many fields in computer science, particularly at higher levels. In academia, success and promotion are influenced by a researcher's publication record. In many fields, including computer science, multi-author papers are the norm. Evidence from other fields shows that author order norms can influence the assignment of credit. We conduct interviews of students and faculty in human-computer interaction (HCI) and machine learning (ML) to determine factors related to assignment of author order in collaborative publication. The outcomes of these interviews then informed metrics of interest for a bibliometric analysis of gender and collaboration in research papers published from 1996 to 2016 in three top HCI and ML conferences. Based on our findings, we make recommendations for assignment of credit in multi-author papers and interpretation of author order, particularly in regard to how this area affects women
Design of a Partial Discharge Test Platform
No full textDesign of a Partial Discharge Test Platform author: Daniel Harmsen thesis advisor (mentor): Dr. Armando Rodrigo Mor abstract: Partial discharge (PD) measurements are an effective tool for insulation diagnostics and assessment. Therefore, a good understanding of these PD measurements is an essential part of an electrical engineer’s background knowledge. During this research project a PD test platform was designed and build for electrical PD detection. The setup included artificially created defects for six different types of PDs, with origins in positive and negative corona, internal discharge, floating electrodes, free-moving particles and surface discharge. These defects were designed to have a partial discharge inception voltage (PDIV) of around 10kV, and could easily be connected or disconnected from the setup. Therefore, it was possible to measure individual defects or a combination of them. This PD test platform was used during this research project to characterize the different PD types (single and multiple), and as a check for testing new clustering and pattern recognition techniques. In addition, the platform could also be used as a test platform for educational purposes and to train people and test equipment. In this thesis research project, the “initial step” towards PD defect origin recognition for AC voltage without any phase dependency was conducted with the use of time-resolved partial discharge (TRPD) analysis. This thesis shows that it is possible to conduct the time analysis and recognition for AC voltage for the artificially created defects. From the analysis in this thesis, it can be concluded that the TRPD analysis for PD recognition under AC voltage is as good as, or even better than, phase-resolved partial discharge (PRPD) analysis. For most of the data analysed, the TRPD analysis provides the same results compared to the PRPD analysis. However, further checking is needed, such as validating the findings with mathematical models. The thesis goals are to build a setup suitable for the research, determining the optimal combination of hardware/software to discriminate among different types of defects, and to realize experiments to validate the design.Electrical Engineering, Mathematics and Computer ScienceDC&E
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