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93.
Yutaka Kawahara Atsushi Nakayama Masatoshi Shioya Masaki Tsuji Hideki Yamane Tadahisa Iwata 《Journal of Materials Science》2012,47(4):1887-1892
Structure of poly(dioxanone) (PPDX) fibers produced through a two-step melt-spinning process with an additional short-period
annealing above the melting temperature of PPDX was investigated and the effect of annealing on the degradation behavior was
discussed. The morphological study carried out by etching the fibers using a phosphate or permanganate solution suggested
that the fibers take a skin–core structure, and both the skin layer and the core region consist of a bundle of microfibrils.
The micro-beam X-ray diffraction analysis revealed that the short-period annealing in the production process only slightly
promotes the crystallization in the skin layer but contributes to increasing the packing of amorphous chains near the skin,
which seems to be the controlling factor of the hydrolytic degradation behavior of the fibers. 相似文献
94.
Atsushi Okuro Hiroyuki Tomita Tsutomu Hihara 《International journal of remote sensing》2014,35(14):5394-5410
In this study, eight global sea surface temperature (SST) products for 2009 are compared to clarify their characteristics. The median of eight daily values, the Ensemble Median as Reference Product (EMRP), is used as a reference product for inter-comparison. The results show that the absolute value of mean differences and the value of root mean square (RMS) differences are higher in single-microwave products such as Advanced Microwave Scanning Radiometer for the Earth observing system (AMSR-E), Tropical Rainfall Measuring Mission Microwave Imager (TMI), and WindSat, than in products such as MicroWave Optimally Interpolated SST (MWOI), Merged satellite and in situ data Global Daily SST (MGD), and Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) constructed by merging several SST data. It is of note that the characteristics of SST products depend on the type of SST used within the product, rather than the data source used. A comparison of SST products was also conducted using EMRP and data observed by moored buoys. The results show that only AMSR-E has a warm bias (+0.06°C) while other products have a cool bias (maximum value ?0.10°C). The RMS error of TMI is the highest (0.57°C), and that of EMRP the lowest (0.28°C). Furthermore, the temporal variability between the data in each SST product was compared to those observed by the Kuroshio Extension Observatory (KEO) buoy. Results show that the temporal variability of EMRP corresponds well to that of buoy data, and that the RMS error of EMRP is lower than that of the other SST products. 相似文献
95.
Yanyan Hou Satoshi Arai Yoshiaki Takei Atsushi Murata Shinji Takeoka 《Science and Technology of Advanced Materials》2016,17(1):293-299
Ca2+ distribution is spatially and temporally non-uniform inside cells due to cellular compartmentalization. However, Ca2+ sensing with small organic dyes, such as fura-2 and fluo-4, has been practically applied at a single cell level where the averaged signal from freely diffusing dye molecules is acquired. In this study, we aimed to target azide-functionalized fura-2 (N3-fura-2) to a specific site of subcellular compartments to realize focal Ca2+ sensing. Using scAVD (single-chain avidin)–biotin interaction and a copper-free click reaction system, we linked N3-fura-2 to specifically-targeted scAVD protein fused with a red fluorescent protein mCherry, so that Ca2+ sensors conjugated with four N3-fura-2 dyes with dibenzocyclooctyne (DBCO)-PEG4-biotin as a linker were generated at subcellular compartments in living cells. In cytoplasm, N3-fura-2 showed a prolonged retention period after binding to scAVD. Furthermore, the reacted N3-fura-2 was retained inside cells even after free dyes were washed out by methanol fixation. When scAVD was overexpressed on endoplasmic reticulum (ER) membranes, N3-fura-2 was accumulated on ER membranes. Upon histamine stimulation, which increases cytosolic Ca2+ concentration, ER-localized N3-fura-2 successfully sensed the Ca2+ level changes at the cytosolic side of ER membrane. Our study demonstrated specific targeting of N3-fura-2 to subcellular compartments and the ability of sensing focal Ca2+ level changes with the specifically targeted Ca2+ sensors. 相似文献
96.
Atsushi Iizuka Satoshi Takeda Kazukiyo Kumagai Yukio Yanagisawa 《Chemical Engineering Communications》2017,204(3):321-326
The effect of the addition of microbubbles on the formation of silver nanoparticles produced in an ultrasonic radiation-mediated process was investigated. The addition of microbubbles with an area-based median diameter of 26.0?µm and a bubble volume density of 0.18?cm3/L significantly increased the silver nanoparticle formation rate during the sonochemical process. The size distribution of the silver nanoparticles was largely unaffected by the addition of the microbubbles. The influence of changes in the microbubble volume density on the formation of the silver nanoparticles was also investigated; it was confirmed that the rate of formation of the silver nanoparticles increased moderately with increasing volume density. The gradient in absorption spectra was approximately 30 times larger for the case when microbubbles (median diameter: 28.3?µm) were added at 0.74?cm3/L, compared with the case without microbubbles. The results suggested that the microbubbles provided reaction sites similar to cavitation bubbles in the ultrasonic reaction. 相似文献
97.
Hsin Wang Robin McCarty James R. Salvador Atsushi Yamamoto Jan König 《Journal of Electronic Materials》2014,43(6):2274-2286
The development of thermoelectrics (TE) for energy conversion is in the transition phase from laboratory research to device development. There is an increasing demand to accurately determine the module efficiency, especially for the power generation mode. For many TE, the figure of merit, ZT, of the material sometimes cannot be fully realized at the device level. Reliable efficiency testing of thermoelectric modules is important to assess the device ZT and provide end-users with realistic values for how much power can be generated under specific conditions. We conducted a general survey of efficiency testing devices and their performance. The results indicated a lack of industry standards and test procedures. This study included a commercial test system and several laboratory systems. Most systems are based on the heat flow meter method, and some are based on the Harman method. They are usually reproducible in evaluating thermoelectric modules. However, different systems often showed large differences that are likely caused by uncertain heat loss and thermal resistance. Efficiency testing is an important capability for the thermoelectric community to improve. A follow-up international standardization effort is planned. 相似文献
98.
Abstract We propose an approach to manipulate the convergence in multiple solutions of phase conjugate reflectivity in photorefractive four-wave mixing. Although a method forcibly adding a π-phase shift to an incident beam has been already proposed to control the reflectivity, some restrictions have been required in the boundary conditions for the successful operation. Here, we control the reflectivity with the boundary conditions in which the phase shift operation is ineffective by itself. In our method, the phase shift operation is combined with the procedure of turning an incident beam on and off. With a numerical analysis of four-wave mixing, we show that our new approach brings drastic change in the spatial distribution of the index grating and leads the phase conjugate reflectivity which was not manipulated previously. 相似文献
99.
Yoshihiro Hayashi Takuya Oishi Kaede Shirotori Yuki Marumo Atsushi Kosugi Shungo Kumada 《Drug development and industrial pharmacy》2018,44(7):1090-1098
Objectives: The aim of this study was to explore the potential of boosted tree (BT) to develop a correlation model between active pharmaceutical ingredient (API) characteristics and a tensile strength (TS) of tablets as critical quality attributes.Methods: First, we evaluated 81 kinds of API characteristics, such as particle size distribution, bulk density, tapped density, Hausner ratio, moisture content, elastic recovery, molecular weight, and partition coefficient. Next, we prepared tablets containing 50% API, 49% microcrystalline cellulose, and 1% magnesium stearate using direct compression at 6, 8, and 10?kN, and measured TS. Then, we applied BT to our dataset to develop a correlation model. Finally, the constructed BT model was validated using k-fold cross-validation.Results: Results showed that the BT model achieved high-performance statistics, whereas multiple regression analysis resulted in poor estimations. Sensitivity analysis of the BT model revealed that diameter of powder particles at the 10th percentile of the cumulative percentage size distribution was the most crucial factor for TS. In addition, the influences of moisture content, partition coefficients, and modal diameter were appreciably meaningful factors.Conclusions: This study demonstrates that BT model could provide comprehensive understanding of the latent structure underlying APIs and TS of tablets. 相似文献
100.
Hirofumi Chiba Yukio Suzuki Yoshiaki Yasuda Mitsuyasu Kumagai Takaaki Koyama Shuji Tanaka 《Electrical Engineering in Japan》2021,214(1):62-68
This paper reports a deep‐ultraviolet LED (deep‐UV‐LED) package based on silicon MEMS process technology (Si‐PKG). The package consists of a cavity formed by silicon crystalline anisotropic etching, through‐silicon vias (TSVs) filled with electroplated Cu, bonding metals made of electroplated Ni/AuSn and a quartz lid for hermetic sealing. A deep‐UV LED die is directly mounted in the Si‐PKG by AuSn eutectic bonding without a submount. It has advantages in terms of size, heat dissipation, light utilization efficiency, productivity and cost over conventional AlN ceramic packages. We confirmed a light output of 30 mW and effective reflection on Si (111) cavity slopes in the Si‐PKG. Based on simulation, further improvement of the optical output is expected by optimizing DUV‐LED die mount condition. 相似文献