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161.
A novel electrolytic transformation of olefins into oxyselenides has been performed in high yields and high regioselectivities by elctrolyzing olefins in protic solvents (MeOH, AcOH, H2O-MeCN) containing Et4NX (X = Cl, Br, I) and diphenyl diselenide using platinum foils. 相似文献
162.
Kazuhiro Tsuji Michio Sorai Hiroshi Suga Syüzö Seki 《Molecular Crystals and Liquid Crystals》2013,570(3-4):305-317
Abstract The heat capacity of HBAF has been measured between 15 K and 385 K. Four phase transitions were found at 328.07 K (crystal-smectic B); 330.33 K (smectic B-smectic A); 334.88 K (smectic A-nematic); and 336.33 K (nematic-isotropic liquid), respectively. The enthalpies and entropies of these transitions were determined to be 23.22 kJ mol?1/70.7 JK?1 mol?1; 3.05/9.2; 3.41/10.2; and 1.17/3.5, respectively. The total transition entropy of HBAF agreed well with those previously reported for the present homologues. The standard thermodynamic functions were estimated up to 385 K. The heat capacity curve of HBAF in the transition region had a close resemblance to that of p-n-hexyloxybenzylideneamino-p'-chlorobenzene. The entropies of the smectic A-nematic and nematicisotropic liquid transitions were compared with those theoretically derived by McMillan. The smectic B-smectic A transition entropy was interpreted in terms of order-disorder phase transition associated with the orientation of molecule. 相似文献
163.
Michio Kobayashi Kentaro Okuma Hiroyuki Takeuchi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2)
Abstract Hitherto, the preparative method of the sulfoxonium ions has been practically limited to thealkylation of the sulfoxides with methyliodide. The yields of the desired sulfoxonium salts by this method are usually poor except that of trimethylsulfoxonium iodide, Diarylalkyl- or triaryl-sulfoxonium ions can not be prepared by this alkylation. 相似文献
164.
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166.
Journal of Radioanalytical and Nuclear Chemistry - Decreasing trends of both 137Cs and 3H activity concentrations and an increasing trend of 3H/137Cs activity ratio at Fukushima Dai-ichi Nuclear... 相似文献
167.
168.
Hirotaka Sato Takuya Yamaguchi Tetsuhiko Isobe Shuichi Shoji Takayuki Homma 《Electrochemistry communications》2010,12(6):765-768
An approach to control the diameter of high-aspect-ratio pores formed into a silicon wafer by an electrochemical etching process is reported. Hole (h+) was involved in the etching reaction and the collection of the h+ was the key factor. Artificial micro-cavities were fabricated on the silicon surface prior to the etching. The depth of the space charge region (SCR), Schottky barrier on the silicon-electrolyte interface, was adjusted regarding the depth of the micro-cavities by applied overpotential and specific resistance of the silicon wafer. The collection of h+ at the tip of the cavity site was widely controlled by the adjusted SCR. Consequently the electrochemically etched domain at the cavity site was actively tuned, and then high-aspect-ratio pore with the controlled diameter was formed. The diameter was tuned by the SCR depth which was controlled by the overpotential and the specific resistance. The diameter tuning mechanism worked under the mask-free condition. 相似文献
169.
Stereoselective synthesis of the chemoattractant sperm-activating and attracting factor (SAAF), isolated from the eggs of the ascidian Ciona intestinalis, was achieved via reductive 1,3-transposition of an allylic alcohol and the axial opening of an epoxide as key steps. This second-generation synthesis improved the total yield of SAAF over that of the first-generation synthesis and provided a key intermediate for synthesizing molecular probes of SAAF. 相似文献
170.
Ryugo S. HAYANO Masaharu TSUBOKURA Makoto MIYAZAKI Akihiko OZAKI Yuki SHIMADA Toshiyuki KAMBE Tsuyoshi NEMOTO Tomoyoshi OIKAWA Yukio KANAZAWA Masahiko NIHEI Yu SAKUMA Hiroaki SHIMMURA Junichi AKIYAMA Michio TOKIWA 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2015,91(8):440-446
BABYSCAN, a whole-body counter (WBC) for small children was developed in 2013, and units have been installed at three hospitals in Fukushima Prefecture. Between December, 2013 and March, 2015, 2707 children between the ages of 0 and 11 have been scanned, and none had detectable levels of radioactive cesium. The minimum detectable activities (MDAs) for 137Cs were ≤3.5 Bq kg−1 for ages 0–1, decreasing to ≤2 Bq kg−1 for ages 10–11. Including the 134Cs contribution, these translate to a maximum committed effective dose of ∼16 µSv y−1 even for newborn babies, and therefore the internal exposure risks can be considered negligibly small.Analysis of the questionnaire filled out by the parents of the scanned children regarding their families’ food and water consumption revealed that the majority of children residing in the town of Miharu regularly consume local or home-grown rice and vegetables, while in Minamisoma, a majority avoid tap water and produce from Fukushima. The data show, however, no correlation between consumption of locally produced food and water and the children’s body burdens. 相似文献