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301.
N Tang Y Yoda N Otani T Kameda A Toriba K Hayakawa M Shima 《Chemical & pharmaceutical bulletin》2012,60(8):962-966
Twenty-one data sets composed of readings collected by atmospheric ozone monitors worn by individuals on their clothing and installed outside their home or office were collected using Ogawa passive ozone samplers in southeastern Hyogo prefecture, Japan from September 12 to 13, 2011. The concentrations of personal and outdoor ozone ranged from not detectable to 23.2?ppb and from 4.7 to 38.3?ppb, respectively. The mean concentration of personal exposure to ozone was 3.7?ppb and was significantly lower than that of outdoor ozone (18.5?ppb). This suggests that the concentrations of outdoor ozone affect personal ozone exposure. However, in this study, we found no correlation between the concentrations of personal ozone and the total time spent outdoors or the time of day the individual was outside. In contrast, the mean concentrations of outdoor ozone were similar to those of ozone measured at the 12 nearest Ambient Monitoring Stations (AMSs). However, when the AMS was situated near a main road, the regional ozone levels were underestimated. 相似文献
302.
303.
Kanazawa H Tsubayashi A Nagata Y Matsushima Y Mori C Kizu J Higaki M 《Journal of chromatography. A》2002,950(1-2):303-308
The chiral separation of loxoprofen was achieved on a chiral column with UV and circular dichroism (CD) detection. The good resolution of four loxoprofen stereoisomers was obtained. The column used for the chiral separation was Chiralcel OJ column (250 x 4.6 mm) using hexane-2-propanol-trifluoroacetic acid (95:5:0.1), as an eluent. The flow-rate was 1.0 ml/min and the detection was at 225 nm. In addition, CD and UV spectra were obtained by stopped flow scanning. The method allows the determination of the stereoisomers of loxoprofen in human plasma after the administration of therapeutic dose of the racemic drug, thus HPLC with CD detector is useful for the stereospecific determination of loxoprofen products in biological samples. 相似文献
304.
Sequence-selective DNA detection using multiple laminar streams: a novel microfluidic analysis method 总被引:1,自引:0,他引:1
On-site detection methods for DNA have been demanded in the pathophysiology field. Such analysis requires a simple and accurate method, rather than high-throughput. This report describes a novel microfluidic analysis method and its application for simple sequence-selective DNA detection. The method uses a microchannel device with a serpentine structure. Sequence-specific binding of probe DNA can be detected at one side of the microchannel. This method is capable of sequence-specific detection of DNA with high accuracy. Single base mutations can also be analyzed. Combination of laminar stream and laminar secondary flow in the microchannel enable specific detection of probe-bound DNA. 相似文献
305.
Yoshio Iwakura Aiko Nabeya Takeshi Nishiguchi 《Journal of polymer science. Part A, Polymer chemistry》1968,6(9):2591-2609
Four thioacylaziridines, 1-thioaroyl-, 1-(N-phenylthiocarbamyl)-, 1-(aryloxythiocarbonyl)-, and 1-(aryldithiooxycarbonyl)aziridines, were found to undergo 1,5-polymerization to giving polymers of polyiminothioether, polyisothiourea, polyiminothiocarbonate, and polyiminodithiocarbonate structure, respectively. The 1,5 polymerization may be explained by the kinetic factors rather than the thermodynamic ones. 相似文献
306.
A micellar solution of sodium dodecylsulfate (SDS) exhibits the property of being separated into two phases due to a temperature change or the addition of salts. The ammine-complexes of copper(II), nickel(II) and palladium(II) reacted with the dodecylsulfate anion to form the corresponding ion-pair, and were extracted into the SDS gel phase. The SDS plays the roles of a pairing-ion for the ammine-complexes and of an extraction medium. The ion-pair extraction mechanism was investigated; the extractability of metals was given by the function of the solubility products of the ion-pairs. This method was applied to the mutual separation of Ni(II)/Cu(II) and Pd(II)/Pt(II). The driving force for the extraction was an electrostatic interaction between the cationic complex and the surfactant anion. The use of the SDS gel as ion-exchanger is also expected. 相似文献
307.
Enhanced infrared ATR spectra were measured for Langmuir films of CuPc deposited on PE and PVdC overlaid on PET, by using thin metal (Ni or Ag) films. The apparent intensity ratios for the bands ascribed to the upper layer were much larger than for those of the lower layer. The ratio depended on the nature as well as the mass thickness of the metal films. The mechanism of the enhancement was discussed in terms of SPP and multiple reflection effects. 相似文献
308.
The reaction products of alpha- or gamma-tocopherol with nitric oxide in the presence of molecular oxygen were isolated and characterized. The consumption of tocopherols and the formation of the major products were monitored by high-performance liquid chromatography (HPLC) by a gradient elution method. The quantitative analysis of these compounds with UV-Vis detectors, however, was interfered by several minor products having similar UV spectra and retention times as those of the major ones. In order to establish a quantitative analytical method for the products, we investigated other detection methods, and found that atmospheric pressure chemical ionization (APCI), LC-MS was a more selective and better analytical method for these compounds. 相似文献
309.
Takeshi Wakamatsu Satoshi Yamada Yoshiko Ozaki Yoshio Ban 《Tetrahedron letters》1985,26(16):1989-1992
Pyrenophorin and colletallol were synthesized in their racemic forms from the corresponding hydroxycarboxylic acids and via stereoselective formation of the requisite trans double bonds after macrocyclization. 相似文献
310.
Yamashita K Ogura D Yamaguchi Y Miyazaki M Briones MP Nakamura H Maeda H 《Analytical and bioanalytical chemistry》2005,382(7):1477-1483
Microfluidic systems enable superior control of fluidics. We have developed a novel size-separation method utilizing secondary flow within a microchannel. Using confocal fluorescence microscopy and computer simulation, we confirmed that separation occurred as a result of specific molecular localization in the curving part of the microchannel. Maximum separation efficiency was achieved by optimizing microchannel design and flow rate for individual separation targets. In addition, more effective separation was achieved by use of plural microchannel curves. This method was used for sequence-selective DNA sensing. Double-stranded DNA formed by hybridization between target DNA and a complementary probe had different elution profiles from those of the single-stranded non-complementary sequence. Moreover, the response depends on the length of the DNA molecules. This method does not require immobilization of either probe or target DNA, because all reactions occurred in the solution phase. Such features may reduce experimental error and the difference between data from different operators. 相似文献