Hoyle-Lyttleton Accretion onto Accretion Disks

We investigate Hoyle-Lyttleton accretion for the case where the central source is a luminous accretion disk. %In classical Hoyle-Lyttleton accretion onto a ``spherical'' source, accretion takes place in an axially symmetric manner around a so-called accretion axis. The accretion rate of the classical Hoyle-Lyttleton accretion onto a non-luminous object and $\Gamma$ the luminosity of the central object normalized by the Eddington luminosity. %If the central object is a compact star with a luminous accretion disk, the radiation field becomes ``non-spherical''. %Although the gravitional field remains spherical. In such a case the axial symmetry around the accretion axis breaks down; the accretion radius $R_{acc}$ generally depends on an inclination angle $i$ between the accretion axis and the symmetry axis of the disk and the azimuthal angle $\phi$ around the accretion axis. %That is, the cross section of accretion changes its shape. Hence, the accretion rate $\dot{M}$, which is obtained by integrating $R_{acc}$ around $\phi$, depends on $i$. % as well as $M$, $\Gamma$, and $v_\infty$. %In the case of an edge-on accretion ($i=90^{\circ}$), The accretion rate is larger than that of the spherical case and approximately expressed as $\dot{M} \sim \dot{M}_{HL} (1-\Gamma)$ for $\Gamma \leq 0.65$ and $\dot{M} \sim \dot{M}_{HL} (2-\Gamma)^2/5$ for $\Gamma \geq 0.65$. %Once the accretion disk forms and the anisotropic radiation fields are produced around the central object,the accretion plane will be maintained automatically (the direction of jets associated with the disk is also maintained). %Thus, the anisotropic radiation field of accretion disks drastically changes the accretion nature, that gives a clue to the formation of accretion disks around an isolated black hole.Comment: 5 figure

A switchable pH-differential unitized regenerative fuel cell with high performance

Regenerative fuel cells are a potential candidate for future energy storage, but their applications are limited by the high cost and poor round-trip efficiency. Here we present a switchable pH-differential unitized regenerative fuel cell capable of addressing both the obstacles. Relying on a membraneless laminar flow-based design, pH environments in the cell are optimized independently for different electrode reactions and are switchable together with the cell process to ensure always favorable thermodynamics for each electrode reaction. Benefiting from the thermodynamic advantages of the switchable pH-differential arrangement, the cell allows water electrolysis at a voltage of 0.57 V, and a fuel cell open circuit voltage of 1.89 V, rendering round-trip efficiencies up to 74%. Under room conditions, operating the cell in fuel cell mode yields a power density of 1.3 W cm¯², which is the highest performance to date for laminar flow-based cells and is comparable to state-of-the-art polymer electrolyte membrane fuel cells

A Glimpse into the History of American English -"The People’s Tongue: Americans and the English Language" (Ilan Stavance (ed.), Restless Books, pp.i-viii, 1-458, 2023)-

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On Endeavors to Collect, Preserve, and Provide Public Access of Items Relating to University History: A Case at a University Museum Overseas

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Spiral Structure in WZ Sagittae around the 2001 Outburst Maximum

Intermediate resolution phase-resolved spectra of WZ Sge were obtained on five consecutive nights (July 23 -- 27) covering the initial stage of the 2001 superoutburst. Double-peaked emission lines of He\textsc{II} at 4686 \AA, which were absent on July 23, emerged on July 24 together with emission lines of C\textsc{III} / N\textsc{III} Bowen blend. Analyses of the He\textsc{II} emission lines using the Doppler tomography revealed an asymmetric spiral structure on the accretion disk. This finding demonstrates that spiral shocks with a very short orbital period can arise during the initial stage of an outburst and may be present in all SU UMa stars.Comment: 5 pages, 8 figures, accepted for publication in PAS

A Survey of the Difference in Language Sensitivity Between Japanese and Americans : A Preliminary Study

論文(Article)The goal of this survey is to discover the difference in sensitivity that Americans and Japanese have towards their languages. Thank you for taking time to cooperate with us by answering the following questions. ...departmental bulletin pape

A Fatal Case of Congenital Langerhans Cell Histiocytosis with Disseminated Cutaneous Lesions in a Premature Neonate

Background. The outcome of neonates with congenital cutaneous Langerhans cell histiocytosis (LCH) is variable. Observations. We report a case of LCH in a female premature neonate born at 33-week gestation. She had disseminated cutaneous lesions, which consisted of hemorrhagic papules and vesicles, with sparse healthy skin areas, and the hands and feet were contracted with scarring and blackened. She was in respiratory failure although no apparent pulmonary or bone lesions on X-rays were noted. Skin biopsy confirmed a diagnosis of LCH due to observation of CD1a+ Langerhans cells, which lacked expression of E-cadherin and CD56. The patient died 57 hours after birth. Conclusions. Based on this case and the literature survey, the outcome of premature babies with congenital cutaneous LCH lesions is noted to be unfavorable, with the majority of such cases suffering from multisystem disease

A Survey of the Differences in Language Sensitivity and Ways of Thinking Between Japanese and Americans

論文(Article)The goal of this survey is to discover the differences in language sensitivity and ways of thinking between Japanese and Americans. Thank you for taking time to cooperate with us by answering the following questions. 1 Gender: Male Female 2 Age: years old 3 Mother Tongue: 4 Second Language: 5 Number of years spent studying second language: years. I. Suppose that you are a college student who comes across a university by the name of Gifu University. (The university that you attend may or may not be Gifu University.) At a student meeting, a decision has been made to make a T-shirt with the university's name on it. The following 4 T-shirts were nominated for candidacy. Note that all 4 versions (kanji, hiragana, katakana, and Roman letters) mean Gifu University. On the following scale of 1 to 5, please express to what degree you would like to wear each T-shirt. (Please circle the number that is most appropriate.)[figure][figure][table][table]departmental bulletin pape

Effects of Social Support and Resilience of Mother who have Children with Neurodevelopmental Disorders on Feelings of Difficulty in Child in Child Rearing and Depression

3KJ00009920999論文Articledepartmental bulletin pape