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991.
Kou Sugawara Takeshi Nobukawa Masanori Yoshida Yoshihiro Sato Kazu Okumura Keiichi Tomishige Kimio Kunimori 《Applied catalysis. B, Environmental》2007,69(3-4):154-163
Effect of the loading amount of Fe over ion-exchanged Fe-MFI catalysts on the catalytic performance of N2O reduction with NH3 was investigated, and the results indicated that the turnover frequency (TOF) was almost constant in the Fe/Al range between 0.05 and 0.40. The activity of N2O + NH3 reaction was much lower than that of N2O + CH4 reaction over Fe-MFI (Fe/Al = 0.40), and the preadsorption of NH3 decreased drastically the activity of N2O + CH4 reaction. The temperature-programmed desorption (TPD) of NH3 showed the formation of stronger acid sites on Fe-MFI (Fe/Al = 0.24 and 0.40), and the amount of the acid sites agrees well with the desorption amount O2 in O2-TPD in the low temperature range. The acid sites gave a 3610 cm−1 peak (Brønsted acid) in FTIR observation. These results suggest that the acid sites were formed on the bridge oxide ions in binuclear Fe species. Adsorbed NH3 on the strong acid sites inhibited N2O dissociation, which can be related to the low activity of N2O + NH3 reaction over Fe-MFI with high Fe loading. 相似文献
992.
This study investigates the phenomenon of water freezing below the freezing point in polymer electrolyte fuel cell (PEFCs). Water generated on the surface of the catalyst layer was observed simultaneously with visible and infrared images. Surprisingly, it was found that water generated below the freezing point is in the liquid state and that the temperature rises to 0 °C at the time of freezing. It is generally known that heat of solidification is radiated when water in a super-cooled state starts to freeze. This study shows that water generated below the freezing point in polymer electrolyte fuel cells (PEFCs) is in a super-cooled state. 相似文献
993.
994.
Takuya Sakamoto Terutsugu Koya Misa Togi Kenichi Yoshida Tomohisa Kato Jr. Yasuhito Ishigaki Shigetaka Shimodaira 《International journal of molecular sciences》2022,23(15)
Human dendritic cell (DC) dexosomes were evaluated for their function and preclinical validation for vaccines. Dexosomes are small DC-secreted vesicles that contain absorbing immune signals. Vaccine manufacturing requires a significant number of monocyte-derived DCs (Mo-DCs) from donor blood; thus, Mo-DC dexosomes are expected to serve as novel materials for cancer vaccination. In this study, we characterized a potential dexosome model using immature and mature MUTZ3-derived DCs (M-imIL-4-DC, M-imIFN-DC, M-mIL-4-DC, and M-mIFN-DC) and their dexosomes (M-imIL-4-Dex, M-imIFN-Dex, M-mIL4-Dex, and M-mIFN-Dex). Despite the lack of significant differences in viability, M-mIFN-DC showed a significantly higher level of yield and higher levels of maturation surface markers, such as CD86 and HLA-ABC, than M-mIL-4-DC. In addition, M-mIFN-Dex expressed a higher level of markers, such as HLA-ABC, than M-mIL-4-Dex. Furthermore, M-mIFN-Dex exhibited a higher level of antigen presentation potency, as evaluated using a MART-1 system, than either M-imIFN-Dex or M-mIL-4-Dex. We found that M-mIFN-Dex is one of the four types of MUTZ3-derived DCs that harbor potential immunogenicity, suggesting that DC dexosomes could be useful resources in cancer immunotherapy. 相似文献
995.
Takahashi S Yoshida K Shimada K Nishita T 《IEEE transactions on visualization and computer graphics》2006,12(5):1141-1148
This paper presents a method for occlusion-free animation of geographical landmarks, and its application to a new type of car navigation system in which driving routes of interest are always visible. This is achieved by animating a nonperspective image where geographical landmarks such as mountain tops and roads are rendered as if they are seen from different viewpoints. The technical contribution of this paper lies in formulating the nonperspective terrain navigation as an inverse problem of continuously deforming a 3D terrain surface from the 2D screen arrangement of its associated geographical landmarks. The present approach provides a perceptually reasonable compromise between the navigation clarity and visual realism where the corresponding nonperspective view is fully augmented by assigning appropriate textures and shading effects to the terrain surface according to its geometry. An eye tracking experiment is conducted to prove that the present approach actually exhibits visually-pleasing navigation frames while users can clearly recognize the shape of the driving route without occlusion, together with the spatial configuration of geographical landmarks in its neighborhood. 相似文献
996.
997.
Mohamed Elbadawy Yuki Kato Nagisa Saito Kimika Hayashi Amira Abugomaa Mio Kobayashi Toshinori Yoshida Makoto Shibutani Masahiro Kaneda Hideyuki Yamawaki Tetsuya Mizutani Chang-Kweng Lim Masayuki Saijo Kazuaki Sasaki Tatsuya Usui Tsutomu Omatsu 《International journal of molecular sciences》2021,22(19)
Various pathogens, such as Ebola virus, Marburg virus, Nipah virus, Hendra virus, Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV), Middle East Respiratory Syndrome Coronavirus (MERS-CoV), and SARS-CoV-2, are threatening human health worldwide. The natural hosts of these pathogens are thought to be bats. The rousette bat, a megabat, is thought to be a natural reservoir of filoviruses, including Ebola and Marburg viruses. Additionally, the rousette bat showed a transient infection in the experimental inoculation of SARS-CoV-2. In the current study, we established and characterized intestinal organoids from Leschenault’s rousette, Rousettus leschenaultii. The established organoids successfully recapitulated the characteristics of intestinal epithelial structure and morphology, and the appropriate supplements necessary for long-term stable culture were identified. The organoid showed susceptibility to Pteropine orthoreovirus (PRV) but not to SARS-CoV-2 in experimental inoculation. This is the first report of the establishment of an expandable organoid culture system of the rousette bat intestinal organoid and its sensitivity to bat-associated viruses, PRV and SARS-CoV-2. This organoid is a useful tool for the elucidation of tolerance mechanisms of the emerging rousette bat-associated viruses such as Ebola and Marburg virus. 相似文献
998.
Nozoe A. Kotani H. Tsujikawa T. Yoshida K. Furusawa K. Kato M. Nishimoto T. Kume H. Kurata H. Miyamoto N. Kubono S. Kanamitsu M. Koda K. Nakayama T. Kouro Y. Hosogane A. Ajika N. Koyashi K. 《Solid-State Circuits, IEEE Journal of》1999,34(11):1544-1550
A 256-Mb flash memory is fabricated with a 0.25-μm AND-type memory cell and 2-bit/cell multilevel technique on a 138.6-mm2 die. Parallel decoding of four memory threshold voltage levels to 2-bit logical values prevents throughput degradation due to multilevel operation. This parallel decoding has been achieved by sense latches and data latches connected to each bitline. Tight distribution of memory cell threshold voltage is essential to reliable multilevel operation. This chip has several measures to deal with the factors that widen the memory cell Vth. The effect of adjacent memory cell's Vth is eliminated by using an AND-type flash memory cell. An initial distribution width of 0.1 V is achieved. The wordline voltage, which has negative temperature dependency, compensates the positive dependency of memory cell Vth. In the -5-75°C range, memory threshold Vth deviation is reduced from the conventional 0.19-0.07 V. Conventionally, the number of programs without erase operation per one sector is limited by the limitations from program disturb. This chip introduced a new rewrite scheme, and this limit is increased from the conventional 10-2048+64 times/sector 相似文献
999.
Tomoyuki Yoshida Shoji Hashimoto Yasuichi Mitsushima Takeshi Ohwaki Yasunori Taga 《Microelectronics Reliability》1999,39(3):347
The effect of residual gas constituents and substrate temperature during Ti sputtering on the texture of TiN/Ti films deposited on SiO2/Si substrates has been investigated. The Ti(002) and TiN(111) preferred texture of the films deposited at 350°C was found to be improved drastically by increasing the H2O partial pressure from 1×10−9 to 3×10−8 Torr. Both of the Ti(002) and TiN(111) textures showed a similar H2O partial pressure and substrate temperature dependence because of the epitaxial transfer between these planes. The improved Ti(002) texture was attributed to the self-assembly of Ti atoms on the SiO2 surface, which had a low surface free energy due to the formation of surface OH groups. Two kinds of layered Al-alloy interconnects, AlSiCu/Ti/TiN/Ti and AlCu/TiN/Ti, were fabricated with the highly textured TiN/Ti film, and their Al(111) texture and electromigration lifetime were then evaluated. It was confirmed that both of the interconnects have strong Al(111) texture and longer EM lifetimes. 相似文献
1000.
Shibata T. Shinohara S. Ikeda H. Yoshida H. Sumi M. 《IEEE transactions on instrumentation and measurement》1999,48(6):1062-1067
We propose and demonstrate to automatically measure both a velocity and a length of a moving plate, employing a novel laser speckle velocimeter using a self-mixing laser diode (SM-LD). We derive two empirical equations including velocity of length of a moving plate made of white paper or plastic. After determining a pair of constants fs(0) and β in advance calibration, we can automatically obtain velocity or length from the measured mean speckle signal frequency and/or the number of speckle pulses counted during the measuring time. The investigated range of velocity and length is 100 mm/s to 950 mm/s, and 10 mm to 100 mm, respectively. The measurement accuracy of the velocity and the length is approximately 1% and a few percent, respectively 相似文献