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71.
Kazuaki Kanai Yoshifumi Fukui Takahiro Kozawa Akira Kondo Makio Naito 《Advanced Powder Technology》2017,28(1):50-54
Here, we report on the effect of BaF2 powder addition on the mechanical synthesis of Ce3+-doped Y3Al5O12 (Y2.97Al5O12:Ce0.033+, YAG:Ce3+) phosphors for white light emitting diodes. The YAG phosphors were synthesized by the mechanical method using an attrition-type mill. When BaF2 was added at 6 wt% to the raw powder materials and milled, the synthesis of YAG:Ce3+ was favorably achieved at the vessel temperature of 255 °C, which was about 1200 °C lower than the YAG phosphor synthesis temperature by solid-state reaction. The synthesized YAG:Ce3+ phosphor revealed the maximum internal quantum yield of 57%. 相似文献
72.
Yoshifumi Okabe 《Polymer》2004,45(25):8485-8490
Melting and crystallization behavior in mixtures of poly(vinylidene fluoride) (PVDF) and several ethylene-vinyl acetate copolymers (EVAc) with various ethylene contents have been investigated by means of differential scanning calorimetry, atomic force microscope, and optical microscopy. PVDF/EVAc-80 exhibits the melting point depression of PVDF crystals, suggestive of a miscible character of the pair. Crystallization behavior and morphology development in blends of PVDF/EVAc-80 have been investigated with an emphasis on the spherulitic growth demonstrating the spiral and concentric ringed (or target) patterns. Of particular interest is the break-up of the spiral or concentric ringed patterns at very shallow supercoolings, which may be attributed to instabilities driven by the exclusion of amorphous PVDF and EVAc chains into the emerging inter- and intra-spiral (or target) lamellar regions. 相似文献
73.
Tomoki Nakayama Yutaka Matsumi Keiko Kawahito Yoshifumi Watabe 《Aerosol science and technology》2018,52(1):2-12
A new palm-sized optical PM2.5 sensor has been developed and its performance evaluated. The PM2.5 mass concentration was calculated from the distribution of light scattering intensity by considering the relationship between scattering intensity and particle size. The results of laboratory tests suggested that the sensor can detect particles with diameters as small as ~0.3 µm and can measure PM2.5mass concentrations as high as ~600 µg/m3. Year-round ambient observations were conducted at four urban and suburban sites in Fukuoka, Kadoma, Kasugai, and Tokyo, Japan. Daily averaged PM2.5 mass concentration data from our sensors were in good agreement with corresponding data from the collocated standard instrument at the Kadoma site, with slopes of 1.07–1.16 and correlation coefficients (R) of 0.90–0.91, and with those of the nearest observatories of the Ministry of the Environment of Japan, at 1.7–4.1 km away from our observation sites, with slopes of 0.97–1.23 and R of 0.89–0.95. Slightly greater slopes were observed in winter than in summer, except at Tokyo, which was possibly due to the photochemical formation of relatively small secondary particles. Under high relative humidity conditions (>70%), the sensor has a tendency to overestimate the PM2.5 mass concentrations compared to those measured by the standard instruments, except at Fukuoka, which is probably due to the hygroscopic growth of particles. This study demonstrates that the sensor can provide reasonable PM2.5 mass concentration data in urban and suburban environments and is applicable to studies on the environmental and health effects of PM2.5.
Copyright © 2018 American Association for Aerosol Research 相似文献
74.
75.
In this paper, we introduce a probabilistic distribution, called a smooth distribution, which is a generalization of variants of the uniform distribution such as q-bounded distribution and product distribution. Then, we give an algorithm that, under the smooth distribution, properly learns the class of functions of k terms given as
k
kn={g(f1(v), …, fk(v)) | g
k, f1, …, fk
n} in polynomial time for constant k, where
k is the class of all Boolean functions of k variables and
n is the class of terms over n variables. Although class
k
kn was shown by Blum and Singh to be learned using DNF as the hypothesis class, it has remained open whether it is properly learnable under a distribution-free setting. 相似文献
76.
Yoshifumi Nagano Akihiro Orita Junzo Otera 《Advanced Synthesis \u0026amp; Catalysis》2003,345(5):643-646
The high atom efficiency was achieved through addition of Ac2O in the Sc(OTf)3‐catalyzed allylation of aldehyde with tetraallytin in a 4 : 1 molar ratio. 相似文献
77.
Tomohisa Nakae Yasunori Kanamaru Yoshifumi Amemiya 《Electrical Engineering in Japan》1998,122(4):55-62
We propose a method of single-phase PWM for an independent power supply in photovoltaic power generation systems. This new PWM is derived by comparing levels of signal waves with one of carrier waves which have bipolar swing different from unipolar swing in the conventional PWM. In this PWM, we can use a battery with lower voltage in combination with the photovoltaic power generation; fundamental level of output voltage is raised by about 11%, though poor in quality of waveforms. © 1998 Scripta Technica. Electr Eng Jpn, 122(4): 55–62, 1998 相似文献
78.
Suzuki Y Tsujimoto Y Matsui H Watanabe K 《Journal of Bioscience and Bioengineering》2006,102(2):73-81
Hard-to-degrade animal proteins are ubiquitously present throughout animal bodies. Enormous numbers of these proteins generated in the meat industry are converted to industrial wastes, the disposal of which is tremendously difficult. Most hard-to-degrade animal proteins are currently disposed of by incineration; however, this method has ecological disadvantages in terms of an apparent energy loss and the production of a large amount of carbon dioxide. As a result, an innovative solution to these problems has been sought. In this review, we focus on the degradation of three hard-to-degrade animal proteins (extracellular matrix proteins, collagen in particular, keratin, and prion proteins) and discuss the decomposing capability of thermophilic bacteria. These proteins are strongly resistant to proteinases because of their structural features; therefore, new approaches employing bacterial proteases with strong activity and broad specificity are required for practical application. 相似文献
79.
Masago Y Katayama H Watanabe T Haramoto E Hashimoto A Omura T Hirata T Ohgaki S 《Environmental science & technology》2006,40(23):7428-7433
Noroviruses are one of the major causes of viral gastroenteritis in Japan. A quantitative risk assessment was conducted to evaluate the health risk caused by this virus in drinking water. A Monte Carlo analysis was used to calculate both the probability of infection and the disease burden using disability-adjusted life years (DALYs). The concentration of noroviruses in tap water was estimated based on qualitative data and a most probable number (MPN) method with an assumed Poisson lognormal distribution. This numerical method was evaluated using two sets of available count data of Cryptosporidium: that collected from a river and that found in tap water in Japan. The dose-response relationships for noroviruses were estimated using assumed ID50 (10 or 100). The annual risk was higher than the US-EPA acceptable level (10(-4) [infection/ person-year]) but around the WHO level (10(-6) [DALYs/ person-year]). As suggested by others, since microbial concentrations are generally lognormally distributed, the arithmetic mean was directly related to the annual risk, suggesting that the arithmetic mean is more useful in representing the degree of microbial contamination than the geometric mean. 相似文献
80.
Yasuyuki Shirai Hideki Tatsumoto Masahiro Shiotsu Koichi Hata Hiroaki Kobayashi Yoshihiro Naruo Yoshifumi Inatani 《低温学》2010,50(6-7):410-416
Heat transfer from a flat plate facing upward immersed in a liquid hydrogen pool was measured for the pressures from atmospheric to 1.1 MPa. The flat plate heater used was 10 mm in width, 100 mm in length and 0.1 mm in thickness. Critical heat fluxes (CHFs) in saturated boiling increased with the increase in pressure up to around 0.3 MPa and then decreased with further pressure increase. The CHFs under subcooled condition at each pressure increased with the increase in sub-cooling. Discussions were made on the experimental results by comparing with those of the other cryogenic liquids and also the Kutateladze’s equations under saturated and subcooled conditions. The experimental CHFs were much smaller than the Kutateladze’s equation for higher pressure up to critical. The heater surface temperature was found to reach the critical temperature before the occurrence of hydrodynamic instability and jump to the film boiling regime at the lower heat flux in the higher pressure range. It was suggested that the CHFs are determined not by the heat flux but by the temperature in the higher pressure range. 相似文献