We report on the formation of charge-transfer (CT) excitons and their effect on photocurrent dynamics in composites with a fluorinated anthradithiophene (ADT-TES-F) donor (D) and acceptors (A) with ...(i) various LUMO energy offsets with respect to that of the donor (ΔLUMO) and (ii) several different side groups that modify spatial D/A separation at the D/A interface. Exciplexes and nonemissive CT excitons were formed in composites with ΔLUMO <0.6 and >0.6 eV, respectively. A competition between fast charge carrier photogeneration and CT exciton formation was observed, with outcomes depending on the applied electric field (E) and on the D/A separation. At low E fields, CT formation was dominant, and up to a factor of 2 increase in charge photogeneration efficiency due to CT exciton dissociation was observed in composites with large spatial D/A separation compared with that in pristine D films. At high E fields, fast charge carrier photogeneration was dominant in all composites, and no improvement in charge photogeneration efficiency with respect to that in pristine D films was observed. Dramatic changes in charge recombination dynamics were observed depending on the spatial D/A separation. These contributed to a factor of 5–10 improvement in continuous-wave photocurrents in composites with large spatial D/A separation as compared with those in pristine D films.
We report on the dependence of time-resolved photoluminescence (PL) and photocurrent in small-molecule bulk heterojunctions on the donor–acceptor (D/A) LUMO offset, D/A separation, and acceptor ...domain structure. We chose a high-performance functionalized fluorinated anthradithiophene (ADT) derivative, ADT-TES-F, as the donor and two other fluorinated ADT derivatives, ADT-R-F (where R is a variable side group), as well as two functionalized fluorinated pentacene (Pn) derivatives, Pn-R-F8, as acceptors. The choice of ADT and Pn acceptors enabled us to separate the effects of the D/A LUMO offset, which was approximately zero in the case of ADT acceptors and ∼0.55 eV in the case of Pn acceptors, from those of molecular packing on the optoelectronic properties. The acceptor side groups R were chosen based on (i) packing motifs in the solid state and (ii) size, to achieve different D/A separations at the D/A interface. Addition of an ADT-R-F acceptor to the ADT-TES-F donor introduced disorder, which resulted in increased PL emission, depending on the acceptor’s packing motif, and in reduced photocurrents. In ADT-TES-F/Pn-R-F8 films, charge transfer from ADT-TES-F to Pn-R-F8 was observed with an acceptor packing-dependent formation of an exciplex, which dissociated under applied electric field, contributing to charge carrier photogeneration. However, this contribution was not sufficient to compensate for a photocurrent reduction due to an increased disorder at Pn-R-F8 concentrations of 7 wt % and above, regardless of the acceptor’s R-groups and packing motifs.
We report the construction of a three-dimensional template bank for the search for gravitational waves from inspiralling binaries consisting of spinning compact objects. The parameter space consists ...of two dimensions describing the mass parameters and one "reduced-spin" parameter, which describes the secular (nonprecessing) spin effects in the waveform. The template placement is based on an efficient stochastic algorithm and makes use of the semianalytical computation of a metric in the parameter space. We demonstrate that for "low-mass" (m sub(1) + m sub(2) <, ~ 12M sub(middot in circle)) binaries, this template bank achieves effective fitting factors ~ 0.92-0.99 towards signals from generic spinning binaries in the advanced detector era over the entire parameter space of interest (including binary neutron stars, binary black holes, and black-hole neutron-star binaries). This provides a powerful and viable method for searching for gravitational waves from generic spinning low-mass compact binaries. Under the assumption that spin magnitudes of black holes (neutron stars) are uniformly distributed between 0-0.98 0-0.4 and spin angles are isotropically distributed, the expected improvement in the average detection volume (at a fixed signal-to-noise-ratio threshold) of a search using this reduced-spin bank is ~ 20%-52%, as compared to a search using a nonspinning bank.
We report the construction of a three-dimensional template bank for the search for gravitational waves from inspiralling binaries consisting of spinning compact objects. The parameter space consists ...of two dimensions describing the mass parameters and one "reduced-spin" parameter, which describes the secular (non-precessing) spin effects in the waveform. The template placement is based on an efficient stochastic algorithm and makes use of the semi-analytical computation of a metric in the parameter space. We demonstrate that for "low-mass" (\(m_1 + m_2 \lesssim 12\,M_\odot\)) binaries, this template bank achieves effective fitting factors \(\sim0.92\)--\(0.99\) towards signals from generic spinning binaries in the advanced detector era over the entire parameter space of interest (including binary neutron stars, binary black holes, and black hole-neutron star binaries). This provides a powerful and viable method for searching for gravitational waves from generic spinning low-mass compact binaries. Under the assumption that spin magnitudes of black-holes neutron-stars are uniformly distributed between 0--0.98 0 -- 0.4 and spin angles are isotropically distributed, the expected improvement in the average detection volume (at a fixed signal-to-noise-ratio threshold) of a search using this reduced-spin bank is \(\sim20-52\%\), as compared to a search using a non-spinning bank.
The goal of this book is three-fold: it describes the basics of model order reduction and related aspects. In numerical linear algebra, it covers both general and more specialized model order ...reduction techniques for linear and nonlinear systems, and it discusses the use of model order reduction techniques in a variety of practical applications. The book contains many recent advances in model order reduction, and presents several open problems for which techniques are still in development. It will serve as a source of inspiration for its readers, who will discover that model order reduction is a very exciting and lively field.
Abstract
Improved observational constraints on the orbital parameters of the low-mass X-ray binary Scorpius X-1 were recently published in Killestein et al. In the process, errors were corrected in ...previous orbital ephemerides, which have been used in searches for continuous gravitational waves from Sco X-1 using data from the Advanced LIGO detectors. We present the results of a reanalysis of LIGO detector data from the third observing run of Advanced LIGO and Advanced Virgo using a model-based cross-correlation search. The corrected region of parameter space, which was not covered by previous searches, was about 1/3 as large as the region searched in the original O3 analysis, reducing the required computing time. We have confirmed that no detectable signal is present over a range of gravitational-wave frequencies from 25 to 1600 Hz, analogous to the null result of Abbott et al. Our search sensitivity is comparable to that of Abbott et al., who set upper limits corresponding, between 100 and 200 Hz, to an amplitude
h
0
of about 10
−25
when marginalized isotropically over the unknown inclination angle of the neutron star’s rotation axis, or less than 4 × 10
−26
assuming the optimal orientation.
ABSTRACT
Although nurses are increasingly expected to fulfill the role of care coordinator, the knowledge and skills required to be an effective care coordinator are not well understood. The purpose ...of this study was to describe the knowledge and skills required in care coordination practice using an interpretive phenomenological approach. Fifteen care coordinators from 10 programs were interviewed over a 6‐month period. Semi‐structured face‐to‐face interviews were audio recorded, transcribed, and analyzed using interpretive phenomenology. The central theme of care coordination practice was bridging the patient and the healthcare systems. To bridge, care coordinators needed to have knowledge of the patient and healthcare system as well as the skills to identify and negotiate treatments appropriate for the patient. The most salient finding and new to this literature was that care coordinators who used their medical knowledge about available treatment options to discern and negotiate for the most appropriate care to the patient made differences in patient outcomes. Nurses with medical and healthcare system knowledge, combined with the skills to navigate and negotiate with others in an increasingly complex healthcare system, are well situated to be care coordinators and generate optimal outcomes. Further investigations of critical care coordinator competencies are needed to support nurses currently enacting the role of care coordinator and to prepare future nurses to fulfill the role.
This book concerns the origins of mathematical problem solving at the internationally active Osram and Telefunken Corporations during the golden years of broadcasting and electron tube research. The ...woman scientist Iris Runge, who received an interdisciplinary education at the University of Göttingen, was long employed as the sole mathematical authority at these companies in Berlin. It will be shown how mathematical connections were made between statistics and quality control, and between physical-chemical models and the actual problems of mass production. The organization of industrial laboratories, the relationship between theoretical and experimental work, and the role of mathematicians in these settings will also be explained. By investigating the social, economic, and political conditions that unfolded from the time of the German Empire until the end of the Second World War, the book hopes to build a bridge between specialized fields mathematics and engineering and the general culture of a particular era. It hopes, furthermore, to build a bridge between the history of science and industry, on the one hand, and the fields of Gender and Womens Studies on the other. Finally, by examining the life and work of numerous industrial researchers, insight will be offered into the conditions that enabled a woman to achieve a prominent professional position during a time when women were typically excluded from the scientific workforce.
Coordination of care, including the provision of safe and effective transitions, is a core professional standard for nurses. However, as currently designed, prelicensure nursing education prepares ...nurses to function in discrete settings rather than across settings. A teaching-learning innovation focusing on transitional care was implemented as an educational pilot project with 20 senior-level baccalaureate students in their leadership course. Students in the educational pilot immersed in the subject of transitional care via concept-based learning activities and performance improvement projects. During the course, students were assigned to designated clinical sites representative of a continuum of care. An integrated clinical postconference offered students the opportunity to discover the role of the nurse in transitional care from a systems perspective and facilitated a deeper understanding of the subject that extended beyond the walls of students' discrete clinical sites.
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