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91.
Toshiki Sugimura Shinji Kajimoto Takakazu Nakabayashi 《Angewandte Chemie (International ed. in English)》2020,59(20):7755-7760
We propose a label‐free method for measuring intracellular temperature using a Raman image of a cell in the O?H stretching band. Raman spectra of cultured cells and the medium were first measured at various temperatures using a Raman microscope and the intensity ratio of the two regions of the O?H stretching band was calculated. The intensity ratio varies linearly with temperature in both the medium and cells, and the resulting calibration lines allow simultaneous visualization of both intracellular and extracellular temperatures in a label‐free manner. We applied this method to the measurement of temperature changes after the introduction of FCCP (carbonyl cyanide‐p‐trifluoromethoxyphenylhydrazone) in living cells. We observed a temperature rise in the cytoplasm and succeeded in obtaining an image of the change in intracellular temperature after the FCCP treatment. 相似文献
92.
Kei Fujise Eiji Tsurumaki Gaku Fukuhara Nobuyuki Hara Yoshitane Imai Shinji Toyota 《化学:亚洲杂志》2020,15(16):2456-2461
Polycyclic aromatic hydrocarbons consisting of three fused anthracene units were designed as new π‐conjugated compounds having helical structures. These expanded helicenes were synthesized by Pt‐catalyzed cycloisomerization of the corresponding ethynyl‐substituted precursors. The nonplanar and helical structure was confirmed by X‐ray analysis and DFT calculations, and the barrier to helical inversion was estimated to be 34 kJ mol?1. The enantiomers of the diphenyl derivative were successfully resolved by chiral HPLC. Enantiopure samples showed good chiroptical performance in the CD (|Δ?| 1380 L mol?1 cm?1) and CPL (|glum| 0.013) spectra, and these values were considerably large for simple organic molecules. The unique chiroptical properties are discussed on the basis of the molecular structure and the electronic state with the aid of time‐dependent DFT calculations. 相似文献
93.
A. Uedono T. Kawano S. Tanigawa M. Ban M. Kyoto T. Uozumi 《Journal of Polymer Science.Polymer Physics》1996,34(13):2145-2151
Relaxation processes in polyethylene (PE) and polystyrene (PS) were studied by positron annihilation technique. For PE, above the glass transition temperature, Tg, the size of free volumes and its concentration were increased by the micro-Brownian motion of molecules. For PS, local motions of molecules in backbone chains were found to start above 260 K. However, these local motions were suppressed by an interphenyl correlation. For both PE and PS, below 250–260 K, the formation probability of positronium atoms increased with decreasing temperature. This fact was assigned to the freezing in of the local motions of molecules. For PS, an onset of the local motions of molecules was observed above 100 K. These motions were expected to be associated with liberation of phenyl groups. © 1996 John Wiley & Sons, Inc. 相似文献
94.
Megumi Ban Michihisa Kyoto Akira Uedono Takao Kawano Shoichiro Tanigawa 《Journal of Polymer Science.Polymer Physics》1996,34(7):1189-1195
Free volume characteristics in three samples of monodisperse polystyrene were investigated by positron annihilation technique over a temperature range from 300 to 380 K. The number-average molecular weight of the samples ranged from 5730 to 1,524,000. The observed lifetime spectra were resolved into three components, where the longest lifetime, τ3 was associated with the pick-off annihilation of ortho-positronium (o-Ps) trapped by free volumes. The change of the temperature coefficient of τ3 was observed at around 350 K, at which the value of τ3 was a constant value of 2,3 ns for all specimens with different molecular weights. There was no discrete change of τ3 in intensity, which is corresponding to the number of free volumes. The size of free volume at glass transition was evaluated to be 0.l nm3. © 1996 John Wiley & Sons, Inc. 相似文献
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98.
Hiroyuki Kawano Haruhiko Shimoji Shoji Yoshikawa Katsumasa Miyatake Kazumori Hama Shuji Nakamura 《Optical Review》2008,15(2):118-124
Alignment error of an image sensor relative to the optical axis of a star sensor head and alignment errors between four heads
were calculated from pictures taken in an orbital experiment. When comparing the image sensor alignment parameters in the
orbital test and a ground test, both values matched well. By determining the relative relationship of the four heads using
four pictures taken at the same moment in orbit and uploading the parameters to the star sensor system in orbit, the estimated
attitude error was improved from 0.29 to 0.17°, though the accuracy was limited by the ±0.2° determination accuracy of the
satellite itself. We estimated the attitude determination accuracy from separation angles between boresights of the four heads,
calculated from pattern matching between downloaded pictures and a star catalogue. The estimated accuracy, in terms of potential
optical performance, was 0.60 arcmin at 3σ, which is sufficient to satisfy the specification of 1 arcmin. 相似文献
99.
Umakoshi K Yamasaki T Fukuoka A Kawano H Ichikawa M Onishi M 《Inorganic chemistry》2002,41(16):4093-4095
Treatment of pyridine-2-thiol (pytH) with H(2) (60 atm) in the presence of 5-methylpyridine-2-thiolate (5-mpyt)-bridged dinuclear Pt(III), Pt(II), or Pd(II) complexes (1 mol %) in DMF at 150 degrees C for 72 h leads to the formation of pyridine in 3-51% yield. From the (1)H NMR study of the exchange reactions and of the products under D(2) pressure, it is suggested that the catalytic reaction involves bimetallic activation of the pyt ligand followed by the liberation of pyridine and H(2)S. 相似文献
100.
Sato S Ogura Y Miyanaga A Sugimoto T Tanaka K Moriyama H 《Journal of chromatography. A》2002,956(1-2):53-58
Ion chromatography (IC) has been a powerful tool for measuring ionic species in environmental samples such as tap, river and drain waters. Suppressor modules (membrane and disposable column types) have been used for reducing the background of a baseline. A new type of suppressor device, which has a suppressor resin and switching valve was developed. Fresh ionic resin is introduced into a groove for each analysis to perform the suppression of the working eluent. The eluent composition for obtaining higher sensitivity and better resolutions among ionic species and carbonate ion was also investigated. Although carbonate buffers are used for ion separation in general, the separation of carbonate ion from other ions was not achieved. A borate eluent resulted in good resolutions and higher sensitivity. A new column was also developed for obtaining higher column efficiency and resolution. The optimization of anion separation using a new IC system (IC-2001) that consists of a new suppressor device, an anion-exchange column (TSKgel SuperIC-Anion, 150x4.6 mm), an autosampler, a conductivity cell and a pump in a compact module is described. 相似文献