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排序方式: 共有469条查询结果,搜索用时 218 毫秒
41.
The morphology of a cationic polymer of high molecular weight, poly[2-(acryloyloxy)ethyl(trimethyl)ammoniumchloride], adsorbed on to a mica surface in water was observed in situ using the tapping mode of an atomic force microscope with a high-resolution probe. It was found that the morphology of adsorbed polymers changes with time to be lumplike, floclike, and then fibril-like and that it takes surprisingly a long time for the polymers to relax completely in water, even though they are highly charged. Detailed structures of extended polymers are also discussed. 相似文献
42.
We study theoretically the effect of deformed microelliptical cavities on lasing characteristics. We show that the transition of stationary lasing states from unidirectional rotational waves to a mixture of clockwise and anticlockwise rotational waves occurs when the shape of a disk is deformed to that of an ellipse. 相似文献
43.
We have observed lasing in a complicated eigenmode of a quasi-stadium laser diode with an unstable resonator consisting of two curved end mirrors obeying an unstable resonator condition and two straight sidewall mirrors. The laser was fabricated by application of a reactive-ion-etching technique to a molecular beam epitaxy-grown graded-index separate-confinement heterostructure single-quantum-well GaAs/AlGaAs structure. The far-field pattern shows that the lasing mode corresponds to the complicated lowest-loss mode obtained numerically by an extended Fox-Li method. 相似文献
44.
T. Watanabe P. Bydžovský K. Dobashi S. Endo Y. Fujii O. Hashimoto T. Ishikawa K. Itoh H. Kanda M. Katoh T. Kinoshita O. Konno K. Maeda A. Matsumura F. Miyahara H. Miyase T. Miyoshi K. Mizunuma Y. Miura S.N. Nakamura H. Nomura Y. Okayasu T. Osaka M. Oyamada A. Sasaki T. Satoh H. Shimizu M. Sotona T. Takahashi T. Tamae H. Tamura T. Terasawa H. Tsubota K. Tsukada M. Ukai M. Wakamatsu H. Yamauchi H. Yamazaki 《Physics letters. [Part B]》2007
45.
M Yoshikawa H Endo K Hoshino Y Sugawara O Takaiti S Kanda K Imai 《Biomedical chromatography : BMC》1990,4(5):181-187
A new method for the high performance liquid chromatographic (HPLC) determination of N-(N-acetyl-L-methionyl)-O,O-bis(ethoxycarbonyl)dopamine (TA-870), a dopamine prodrug, in biological fluid has been developed. In order to measure with an electrochemical detector (ECD), TA-870 was passed first through an immobilized carboxylesterase column to be converted to the electrochemically active deethoxycarbonylated TA-870 (DEC-TA-870). The properties of this carboxylesterase immobilized on Sepharose 4B were examined by this flow injection system. Hydrolysis of TA-870 with this immobilized carboxylesterase was a maximum at pH 7-8 and 50 degrees C, and the activity decreased in the presence of organic solvent such as acetonitrile. For the determination of TA-870 in biological fluids, an HPLC-immobilized enzyme-ECD system using a column-switching technique was developed. The blood was deproteinized with ethanol, and TA-870 in the ethanol extracts was adsorbed in Bond Elut C18. The dichloromethane eluate from Bond Elut C18 was injected into the HPLC system. The HPLC apparatus was composed of three pumps, two separation columns (LiChrosorb Si 60 and mu Bondasphere), a trap column (Bond Elut), an enzyme column, ECD and the column-switching system. The calibration curve for TA-870 in blood was linear in the range from 2 to 200 ng/mL. This new assay method might be useful also for the determination of other catechol ester compounds. 相似文献
46.
Yui Hayashi Noriharu Takada Wahyudiono Hideki Kanda Motonobu Goto 《Plasma Chemistry and Plasma Processing》2017,37(1):125-135
Pulsed discharge plasma is typical oxidation technology for disposing organic compounds in aqueous solutions. When this electrical discharge plasma was applied in water, it may produce hydrogen peroxide (H2O2) without any catalyst or chemical agent. In order to increase H2O2 production by electrical discharge plasma in water, fine bubbles were introduced into the electrical discharge plasma in this experiment. Bipolar pulsed voltages were applied to cylindrical electrodes in the water while Ar or O2 bubbles were introduced, generating a pulsed discharge plasma. The introduction of the bubbles seemed to enhance the dissociation of water molecules and increased H2O2 formation, especially with O2 bubbling. Dissolved oxygen in the water contributed to H2O2 formation by pulsed discharge plasma with the bubbles, while dissociation of water molecules was the cause of H2O2 formation by pulsed discharge plasma without bubbles. More H2O2 was formed by pulsed discharge plasma with O2 bubbles, because the amount of dissolved oxygen in the water increased upon bubbling with O2. 相似文献
47.
Vu Hong Thang Kohzo Kanda Genta Kobayashi 《Applied biochemistry and biotechnology》2010,161(1-8):157-170
In this work, acetone–butanol–ethanol (ABE) fermentation characteristics of cassava starch and cassava chips when using Clostridium saccharoperbutylacetonicum N1-4 was presented. The obtained results in batch mode using a 1-L fermenter showed that C. saccharoperbutylacetonicum N1-4 was a hyperamylolytic strain and capable of producing solvents efficiently from cassava starch and cassava chips, which was comparable to when glucose was used. Batch fermentation of cassava starch and cassava chips resulted in 21.0 and 19.4 g/L of total solvent as compared with 24.2 g/L of total solvent when using glucose. Solvent productivity in fermentation of cassava starch was from 42% to 63% higher than that obtained in fermentation using corn and sago starches in the same condition. In fermentation of cassava starch and cassava chips, maximum butanol concentration was 16.9 and 15.5 g/L, respectively. Solvent yield and butanol yield (based on potential glucose) was 0.33 and 0.41, respectively, for fermentation of cassava starch and 0.30 and 0.38, respectively for fermentation using cassava chips. 相似文献
48.
Sakamoto M Takeba K Sasamoto T Kusano T Hayashi H Kanai S Kanda M Nagayama T 《Journal of AOAC International》2010,93(4):1340-1346
LC/MS/MS was developed to determine the residues of bithionol (BTN), bromofen (BMF), nitroxynil (NTX), oxyclozanide (OCZ), and tribromsalan (TBS) in milk. Samples were extracted with ethyl acetate and cleaned up by liquid-liquid separation with acetonitrile and n-hexane. The compounds were determined by RP-LC using a C18 column with 0.1% formic acid-methanol. Mass spectral acquisition was performed in the negative mode by applying selected-reaction monitoring. The method was validated in milk spiked with these compounds at 5-600 microg/kg; average recoveries were in the range 83.8-97.1%, with RSD values of 1.4-8.0%. The interassay RSDs were less than 11%. The LODs of these compounds in milk were 0.1 microg/kg. The method was applied to 24 raw milk samples. The concentration of these compounds in all samples was lower than the Japanese maximum residue limits. The method is rapid, sensitive, and specific for monitoring residues of BTN, BMF, NTX, OCZ, and TBS in milk. 相似文献
49.
We propose Raman-induced collinear difference-frequency generation (DFG) as a method to manipulate dynamical magnetization. When a fundamental beam propagates along a threefold rotational axis, this coherent second-order optical process is permitted by angular momentum conservation through the rotational analogue of the umklapp process. As a demonstration, we experimentally obtained polarization properties of collinear magnetic DFG along a [111] axis of a single crystal of antiferromagnetic NiO with micromultidomain structure, which excellently agreed with the theoretical prediction. 相似文献
50.
We study the output from the modes described by the superposition of Gaussian beams confined in the quasi-stadium microcavities. We experimentally observe the deviation from Snell's law in the output when the incident angle of the Gaussian beam at the cavity interface is near the critical angle for total internal reflection, providing direct experimental evidence on the Fresnel filtering. The theory of the Fresnel filtering for a planar interface qualitatively reproduces experimental data, and a discussion is given on small deviation between the measured data and the theory. 相似文献