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41.
A generation method of artificial fluctuation data of wind power output considering smoothing effect
To use realistic wind power fluctuation data is important in simulating frequency change of power systems. It is well known that the smoothing effect must be taken into account when generating the artificial wind power output. Therefore, this paper proposed a new method to generate fluctuation waveform considering smoothing effect based on random number to fulfill the correlation among multiple sites and autoregression model. The effectiveness of the proposed method was tested by using practical wind speed data measured in Tohoku district. 相似文献
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43.
A simple capillary electrophoretic method was developed for the determination of glucosamine using in-capillary derivatisation. Glucosamine in commercial products was extracted with purified water. The CE separation was achieved on an uncoated fused-silica capillary using a 20 mM borate buffer (pH 9.2) containing 5 mM o-phthalaldehyde (OPA) and 5 mM 3-mercaptopropionic acid (MPA) at 25 kV, followed by UV detection at 340 nm. The detector response was linear (r2 > 0.999) in the concentration range 10–1000 μg/mL. The limit of detection (LOD) was 1.3 mg/g. Spiked glucosamine recoveries at 50 and 100 mg/g level were 95.1% and 104.3%, respectively. The method was applied to 16 commercial products. The concentrations of glucosamine were 109–705 mg/g, and the ratios of detected glucosamine content to the labelled value were 88.8–124%. No significant bias was observed (r2 = 0.989, p < 0.01), between results obtained by the proposed CE method and an official colorimetric method (Japanese Health Food & Nutrition Food Association). 相似文献
44.
Ikuko Kakizaki Ayako Miura Takashi Mineta Jinseo Hong Yoji Kato 《Journal of Applied Glycoscience》2017,64(4):83
Salmon cartilage proteoglycan fractions have recently gained favor as ingredients of functional food and cosmetics. An optimal hot water method to extract proteoglycan from salmon cartilage has recently been developed. The extracted cartilage includes hyaluronan and collagen in addition to proteoglycan as counterparts that interact with each other. In this study, biochemical analyses and atomic force microscopical analysis revealed global molecular images of proteoglycan in the hot water extract. More than seventy percent of proteoglycans in this extract maintained their whole native structures. Hyaluronan purified from the hot water extract showed a distribution with high molecular weight similar to hyaluronan considered to be native hyaluronan in cartilage. The current data is evidence of the quality of this hot water cartilage extract. 相似文献
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46.
Yoko Inui Takao Itioka Kaori Murase Ryohei Yamaoka Takao Itino 《Journal of chemical ecology》2001,27(10):2029-2040
The partnership in the Crematogaster–Macaranga ant–plant interaction is highly species-specific. Because a mutualistic relationship on a Macaranga plant starts with colonization by a foundress queen of a partner Crematogaster species, we hypothesized that the foundress queens select their partner plant species by chemical recognition. We tested this hypothesis with four sympatric Macaranga species and their Crematogaster plant-ant species. We demonstrated that foundress Crematogaster queens can recognize their partner Macaranga species by contact with the surface of the seedlings, that they can recognize compounds from the stem surface of seedlings of their partner plant species, and that the gas chromatographic profiles are characteristic of the plant species. These findings support the hypothesis that foundress queens of the Crematogaster plant-ant species select their partner Macaranga species by recognizing nonvolatile chemical characteristics of the stem surfaces of seedlings. 相似文献
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48.
Emilia Choinska Takanari Muroya Wojciech Swieszkowski Takao Aoyagi 《Journal of Polymer Research》2016,23(7):132
The objective of this study was to analyse how macromolecular structure of polylactides influences their properties and degradation rate. To achieve this, novel 2- and 4-armed PDLLA and PLLA (noted as 2b and 4b) were synthesized by ring-opening method. 1,4-butanediol and pentaerythritol were used as initiators and stannous octoate was used as catalyst. The obtained polymers were investigated in terms of molecular weight by size exclusion chromatography, thermal properties by differential scanning calorimetry and thermogravimetry, and hydrophilicity by the contact angle measurements. The in vitro degradation test was carried out in PBS solution at 37 °C by means of the mass loss, water uptake, molecular weight and thermal properties changes. The branched polylactides including 2bPDLLA, 4bPDLLA, 2bPLLA and 4bPLLA were successfully synthesized and the average molecular weights were around 40-45 kDa. The numbers of arms in each polymer just slightly influenced the thermal properties and the contact angle. The crystallinity of 4bPLLA was 23 %, whereas for 2bPLLA it was 41 %. The degradation rates of both 2b and 4bPLLA were similar and the degradation process was similar only during first 7 weeks. After this period, the degradation rate of 4bPDLLA increased. Consequently, thermal properties and degradation profiles of the branched polymers would depend on plural factors, such as chain length and crystallinity in branched structure. 相似文献
49.
Takashi Otani Xue Jiang Kinryo Cho Rino Araki Noriki Kutsumura Takao Saito 《Advanced Synthesis \u0026amp; Catalysis》2015,357(7):1483-1492
Product selectivity control for the synthesis of imidoylindoles and 4‐alkylidenedihydroquinazolines from N‐imidoyl‐o‐alkynylanilines via silver triflate‐catalyzed cycloisomerization or tetrabutylammonium fluoride‐promoted cyclization is described. The product selectivity depends mainly on the catalyst/promoter used, and on the substituents on the alkyne and amidine functions of the substrates.
50.
Shoya Ueno Yuki Nakamura Ken-Ichi Sugioka Masaki Kubo Takao Tsukada Masahito Uchikoshi Hiroyuki Fukuyama 《International Journal of Thermophysics》2017,38(2):16
The normal spectral emissivity of molten Cu–Co alloy with different compositions was measured in the wavelength range of 780 nm to 920 nm and in the temperature range of 1430 K to 1770 K including the undercooled condition by an electromagnetic levitator superimposed with a static magnetic field. The emissivity was determined as the ratio of the radiance from a levitated molten Cu–Co droplet measured by a spectrometer to the radiance from a blackbody calculated by Planck’s law at a given temperature, where a static magnetic field of 2.5 T to 4.5 T was applied to the levitated droplet to suppress the surface oscillation and translational motion of the sample. We found little temperature dependence of the normal spectral emissivity of molten Cu–Co alloy. Concerning the composition dependence, the emissivity decreased markedly above 80 at%Cu and reached that of pure Cu, although its dependence was low between 20 at%Cu and 80 at%Cu. In addition, this composition dependence of the emissivity of molten Cu–Co alloy can be explained well by the Drude free-electron model. 相似文献