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101.
When the underexpanded supersonic jet impinges on the obstacle, it is well known that the self-induced flow oscillation occurs at the specific condition of the pressure ratio in the flowfield, the position of an obstacle and so on. This oscillation is related with the noise problems of aeronautical and other industrial engineering so that the characteristic and the mechanism of self-induced flow oscillation have to be cleared to control the various noise problems. But, it seems that the characteristics of t... 相似文献
102.
Effects of physical-chemical characteristics on the sorption of selected endocrine disruptors by dissolved organic matter surrogates 总被引:3,自引:0,他引:3
Yamamoto H Liljestrand HM Shimizu Y Morita M 《Environmental science & technology》2003,37(12):2646-2657
Sorption coefficients (K(oc) values) of selected endocrine disruptors for a wide variety of dissolved organic matter (DOM) were measured using fluorescence quenching and solubility enhancement. 17beta-Estradiol, estriol, 17alpha-ethynylestradiol, p-nonylphenol, p-tert-octylphenol, and dibutylphthalate were selected as endocrine disruptors. Aldrich humic acid, Suwannee River humic and fulvic acids, Nordic fulvic acid, alginic acid, dextran, and tannic acid were selected as DOM surrogates. The resulting sorption coefficients (log K(oc)) were independent of octanol-water partitioning coefficients (log K(ow)) of the selected endocrine disruptors, indicating the hydrophobic interaction is not the predominant sorption mechanism. Moreover, the K(oc) values for the selected endocrine disruptors, especially the steroid estrogens, correlated much better with UV absorptivity at 272 nm (A272) and phenolic group concentration of the DOM than with either the H/O or the (O+N)/C atomic ratio of the DOM. This suggests that the sorption mechanism is closely related to the interaction between pi-electrons and the hydrogen bonds, i.e., the affinity between phenolic groups of the steroid estrogens and DOM is suggested to provide a relatively large contribution to the overall sorption and yield the K(oc) values of the steroid estrogens as high as those of the alkylphenols and dibutylphthalate, which are suggested to be dominated by nonspecific hydrophobic interaction. 相似文献
103.
On‐Line Detection Of State‐Of‐Charge In Lead Acid Battery Using Radial Basis Function Neural Network
To realize a stable supply of electric power in an automobile, an accurate and reliable detection method of SOC (state‐of‐charge) in a lead acid battery is required. However the dynamics of the battery is very complicated. The characteristics of the battery greatly change due to its degradation. Moreover a automobile has many driving patterns, which are unknown beforehand. Thus it is not easy to detect the SOC analytically. In this paper, to overcome this problem, a new on‐line SOC detection method with a radial basis function neural network is proposed. In order to increase the detection accuracy of degraded batteries, physical values related to the degradation degree are used as input signal in the neural network. The detection accuracies for different sized batteries and various degradation states are investigated. 相似文献
104.
105.
Takanori Kondo Chihiro Yasui Dr. Taisuke Banno Prof. Dr. Kouichi Asakura Dr. Tokuma Fukuoka Dr. Kazunori Ushimaru Dr. Maito Koga Dr. Hiroyuki Minamikawa Dr. Azusa Saika Dr. Tomotake Morita Prof. Dr. Daisuke Takahashi Prof. Dr. Kazunobu Toshima 《Chembiochem : a European journal of chemical biology》2022,23(2):e202100631
Mannosylerythritol lipids (MELs), which are one of the representative sugar-based biosurfactants (BSs) produced by microorganisms, have attracted much attention in various fields in the sustainable development goals (SDGs) era. However, they are inseparable mixtures with respect to the chain length of the fatty acids. In this study, self-assembling properties and structure-activity relationship (SAR) studies of recovery effects on damaged skin cells using chemically synthesized MELs were investigated. It was revealed, for the first time, that synthetic and homogeneous MELs exhibited significant self-assembling properties to form droplets or giant vesicles. In addition, a small difference in the length of the fatty acid chains of the MELs significantly affected their recovery effects on the damaged skin cells. MELs with medium or longer length alkyl chains exhibited much higher recovery effects than that of C18-ceramide NP. 相似文献
106.
Tetsuya Iida Dr. Yukihiro Itoh Yukari Takahashi Dr. Yasunobu Yamashita Dr. Takashi Kurohara Dr. Yuka Miyake Prof. Makoto Oba Prof. Takayoshi Suzuki 《ChemMedChem》2021,16(10):1609-1618
Lysine demethylase 5 C (KDM5C) controls epigenetic gene expression and is attracting great interest in the field of chemical epigenetics. KDM5C has emerged as a therapeutic target for anti-prostate cancer agents, and recently we identified triazole 1 as an inhibitor of KDM5C. Compound 1 exhibited highly potent KDM5C-inhibitory activity in in vitro enzyme assays, but did not show strong anticancer effects. Therefore, a different approach is needed for the development of anticancer agents targeting KDM5C. Here, we attempted to identify KDM5C degraders by focusing on a protein-knockdown strategy. Compound 3 b , which was designed based on compound 1 , degraded KDM5C and inhibited the growth of prostate cancer PC-3 cells more strongly than compound 1 . These findings suggest that KDM5C degraders are more effective as anticancer agents than compounds that only inhibit the catalytic activity of KDM5C. 相似文献
107.
Boron removal by titanium addition in solidification refining of silicon with Si-Al melt 总被引:4,自引:0,他引:4
Takeshi Yoshikawa Kentaro Arimura Kazuki Morita 《Metallurgical and Materials Transactions B》2005,36(6):837-842
In order to effectively remove B from Si for its use in solar cells, a process involving B removal by solidification refining
of Si using a Si-Al melt with Ti addition was investigated. For clarifying the effect of Ti addition on B removal from the
Si-Al melt, TiB2 solubilities in Si-64.6 at. pct Al melt at 1173 K and Si-60.0 at. pct Al melt at 1273 K were determined by measuring the
equilibrium concentrations of B and Ti in the presence of TiB2 precipitates. The small solubilities of TiB2 in the Si-Al melt indicate the effective removal of B from the Si-Al melt by Ti addition. Further, solidification experiments
of Si-Al alloys containing B by Ti addition were performed, and the effect of Ti addition on the solidification refining of
Si with the Si-Al melt was successfully confirmed. 相似文献
108.
Y. Takei R. Fujimoto Y. Ishisaki U. Morita K. Tanaka T. Koga K. Mitsuda T. Ohashi N. Y. Yamasaki N. Iyomoto T. Ichitsubo K. Sato T. Fujimori T. Oshima K. Futamoto K. Shinozaki T. Morooka S. Nakayama K. Yoshida N. Takai K. Chinone 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2004,520(1-3):340-343
We are developing transition edge sensor (TES) microcalorimeter arrays for future Japanese astronomy missions. Although 6.6 eV energy resolution for 5.9 keV and 74 μs decay time are achieved, our energy resolution was limited by the excess noise of unknown origin. The dominant noise showed 1/R dependence and it only appeared when the current through the TES, I, is larger than 10 μA. This is explained if we assume a constant voltage noise source with a level of 2(4kTCRn)1/2. We also investigated the influence of I on the TES performance and found the TES sensitivity is reduced when the ratio of current to the critical current I/IC is large. It can explain the reduction of observed when operated without a magnetic shield. We also found a strong correlation between IC and or the baseline width. Thus, we conclude that IC is an essential parameter for the TES performance. 相似文献
109.
110.
Masayuki Morita Ryo Arizono Nobuko Yoshimoto Minato Egashira 《Journal of Applied Electrochemistry》2014,44(4):447-453
The electrochemical activation process of the so-called “alkali-treated soft carbon” (ASC) has been examined in organic electrolyte solutions. SEM observation demonstrated that the edge plane of graphene structure of the ASC particle becomes rough after the activation, and XRD measurements indicated that the average lattice constant of graphene stacking in ASC increases after the activation process. Ex-situ 7Li NMR measurements proved that the insertion of cation (Li+) into the pore structure of ASC is associated with the activation process in the electrolyte dissolving Li salt. The pore-size distribution determined from N2-gas adsorption for ASC electrodes before and after the electrochemical activation indicates that the pore structure becomes developed after the electrochemical polarization, especially in the pore-diameter range of 2–10 nm. A schematic model of the activation process has been presented, which includes electrochemical insertion of ions into the inside of the ASC. 相似文献