23 research outputs found
Kinetic Study of Denitrification and Hydrogen Production from NH3/H2O over Ni-loaded Catalysts
学位記番号:工博甲49
Optical Responses of Localized and Extended Modes in a Mesoporous Layer on Plasmonic Array to Isopropanol Vapor
Mesoporous silica features open and accessible
pores that can intake substances from the outside. The
combination of mesoporous silica with plasmonic nanostructures
represents an interesting platform for an optical sensor based on
the dependence of plasmonic modes on the refractive index of the
medium in which metallic nanoparticles are embedded. However,
so far only a limited number of plasmonic nanostructures are
combined with mesoporous silica, including random dispersion of
metallic nanoparticles and
fl
at metallic thin
fi
lms. In this study, we
make a mesoporous silica layer on an aluminum nanocylinder
array. Such plasmonic arrangements support both localized surface
plasmon resonances (LSPRs) and extended modes which are the
result of the hybridization of LSPRs and photonic modes
extending into the mesoporous layer. We investigate
in situ
optical re
fl
ectance of this system under controlled pressure of
isopropanol vapor. Upon exposure, the capillary condensation in the mesopores results in a gradual spectral shift of the re
fl
ectance.
Our analysis demonstrates that such shifts depend largely on the nature of the modes; that is, the extended modes show larger shifts
compared to localized ones. Our materials represent a useful platform for the
fi
eld of environmental sensingEspaña MINECO grant MAT2017-88584-R
Cell competition with normal epithelial cells promotes apical extrusion of transformed cells through metabolic changes
Learning Support and Evaluation of Weight-shifting Skills for Novice Skiers Using Virtual Reality
In this study, we propose a virtual reality learning support system designed to help train novice skiers. In previous research, we extracted the differences between the weight shifting movements and skiing postures of experts and beginners using deep learning. The obtained results showed weight shifting to be a more important feature than posture. Accordingly, we focused on supporting the weight-shifting technique. The support system provides real-time feedback to a user on their current weight-shifting status. We conducted an experiment to verify the effectiveness of the proposed approach, in which we defined evaluation criteria for a user’s level of skiing proficiency. The experimental results demonstrate that the system successfully facilitated participants’ acquisition of the weight-shifting skill.HCII 202
Power Doppler signal calibration in the finger joint between two models of ultrasound machine: a pilot study using a phantom and joints in patients with rheumatoid arthritis
Background: Despite the advantages of ultrasound (US) in the management of rheumatoid arthritis (RA) patients, power Doppler (PD) US may be highly dependent on the type of US machine used. Purpose: To present a method to calibrate the PD signal of two models of US machines by use of a flow phantom and finger joints of patients with RA. Material and Methods: For the phantom study, the PD signal count was measured in the flow phantom perfusing blood mimicking fluid at various injection rates and pulse repetition frequencies (PRFs). The quantitative PD index was calculated with ImageJ. For the clinical study, the second and third metacarpophalangeal joints of five consecutive patients with RA were examined. The quantitative PD index was measured at various PRFs by use of two models of machine (the same models as the phantom study). Results: For the phantom and clinical studies, negative correlations were found between the PRF and the quantitative PD index when the flow velocity was constant and positive correlations between flow velocity and the quantitative PD index at constant PRF. There was a significant difference in the depiction performance of synovial blood flow between the two models, which can be calibrated by adjusting the PRF values derived from the phantom study in each model. Conclusion: Signal calibration of pannus vascularity between US machines may be possible by adjusting the PRF value according to flow phantom data. Different US machines can thus provide equivalent examination results concerning the pannus vascularity
Differential Diagnosis of Histiocytic Necrotizing Lymphadenitis and Malignant Lymphoma with Simple Clinical Findings
It is desirable that noninvasive differential diagnosis takes place without lymph node biopsy for histiocytic necrotizing lymphadenitis (HNL) or malignant lymphoma (ML). In this study, we propose a novel scoring model for the differential diagnosis of these diseases using clinical information and clinical findings. We retrospectively analyzed the data from 15 HNL and 13 ML pediatric patients. First, a univariate analysis identified 14 clinical factors with significant differences. Second, a subsequent analysis using receiver operating characteristic (ROC) curve analysis identified three factors among them with area under the ROC curve values of >0.95: body temperature (°C), maximum lymph node size (cm), and serum β2-microglobulin level (mg/L). Finally, the cut-off values of each of these three factors were determined and examined for the 28 cases. All 15 HNL cases were within 2–3 of the cut-off values among the three factors, no ML case was within two or more cut-off values. Thus, the diagnostic sensitivity and specificity of this novel scoring system were both 100%, indicating that clinical scoring with body temperature, maximum lymph node size, and β2-microglobulin are useful for distinguishing between HNL and ML
Ammonia decomposition activity over Ni/SiO2 catalysts with different pore diameters
Ammonia decomposition over Ni-loaded SiO2 catalysts (Ni/SiO2) was observed in a fixedbed
reactor at different temperatures (ranging from 773 to 973 K) and ammonia feeding
rates (ranging from 1200 to 18,000 h1). As support materials, several porous and inert SiO2
particles with different mean pore diameters ðdÞ ranging from 7.7 to 34.8 nm were used to
clarify the effect of pore diameter on the kinetic parameters for catalytic ammonia
decomposition. The Ni/SiO2 catalyst with the smallest pores, d ¼ 7.7 nm, showed the
highest activity at temperatures below 923 K, while the activity of this catalyst at 973 K was
lower than that of catalysts with larger pores. Kinetic analysis indicated that the activation
energy for d ¼ 7.7 nm was significantly decreased at higher temperatures, suggesting the
occurrence of strong diffusion resistance of ammonia molecules in the pores. Our experiments
also confirmed that almost complete decomposition of ammonia could be achieved
over Ni/SiO2 with d ¼ 26.7 nm at 973 K and a gas hourly space velocity as high as 42,000 h1