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1.
2.
S Morimoto Y Hiraki I Togami M Kaji H Niiya I Joja H Yamamoto K Aono S Suzuki M Sunada 《Radioisotopes》1984,33(10):691-698
The mechanism of 201Tl chloride accumulation is unclear in thyroid gland and thyroid tumor. This report examines 108 patients that received thyroid scintigraphy examinations with both 201Tl chloride and sodium 131I. The patients were diagnosed clinically and histologically whenever possible. The ROI were obtained by subtraction imaging with both isotopes and by subtraction positive and negative areas of imaging. Dynamic curves were obtained for 201Tl chloride per square unit of each ROI. The dynamic curve in the radioiodide-accumulated area was examined. The data indicate that the clearance rate of 201Tl chloride (T15) was correlated with the sodium 131I uptake rate at 24 h (r = 0.70). 相似文献
3.
Angle-resolved photoemission measurements for GaAs(110) have been extended to hv= 100 eV. These results show that dominant emission peaks are due to direct transitions. Weaker one-dimensional density of states features sometimes observed are due to surface umklapp/secondary cone and lifetime effects. Accurate band dispersions for all four valence bands GaAs along the [110] direction are given using simple normal emission and off-normal emission methods. Electron and hole lifetimes are directly determined. 相似文献
4.
Syuji Fujii Shinji Yamashita Yuichi Kakigi Kodai Aono Sho Hamasaki Shin-ichi Yusa Yoshinobu Nakamura 《Colloid and polymer science》2013,291(5):1171-1180
Hydroxy-functional macrodisulfides have been synthesized by atom transfer radical polymerization of 2-hydroxyethyl methacrylate or 2-hydroxypropyl methacrylate in 2-propanol. Mean degrees of polymerization of the polymer chains beside the disulfide were fixed at 30, 60, and 90; since ATRP has reasonably good living character, the molecular weight distribution is relatively narrow. Furthermore, the macrodisulfides were reduced to synthesize corresponding thiol-terminated polymers with relatively narrow molecular weight distributions. 1H nuclear magnetic resonance and gel permeation chromatography were used to characterize the macrodisulfides and thiol-terminated polymers in terms of their chemical structure, molecular weight, and polydispersity, respectively. Dispersion polymerizations of styrene using the thiol-terminated hydroxy-functional polymers as a transtab (chain transfer agent + colloidal stabilizer) in ethanol resulted in colloidally stable submicrometer-sized polystyrene latex particles. Scanning electron microscopy, Fourier transform infrared spectroscopy, and elemental microanalysis were used to characterize the particles in terms of their morphologies, particle sizes and their distributions, and chemical compositions. 相似文献
5.
Chiral Phosphoric‐Acid‐Catalyzed Transfer Hydrogenation of Ethyl Ketimine Derivatives by Using Benzothiazoline 下载免费PDF全文
Dr. Kodai Saito Kosaku Horiguchi Yukihiro Shibata Prof. Dr. Masahiro Yamanaka Prof. Takahiko Akiyama 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(25):7616-7620
Chiral phosphoric acid catalyzed transfer hydrogenation of ketimines derived from propiophenone derivatives and reductive amination of alkyl ethyl ketone derivatives were extensively examined in the presence of two representative hydrogen donors. The excellent enantioselective transfer hydrogenation was achieved by use of benzothiazoline as a hydrogen donor. The theoretical studies elucidated that the unsymmetrical structure of benzothiazoline plays an important role in high enantioselective hydrogenation. 相似文献
6.
Nobuaki Kitazawa Dhebbajaji Yaemponga Masami Aono Yoshihisa Watanabe 《Journal of luminescence》2009,129(9):1036-1041
Thin films of microcrystalline (C8H17NH3)2PbBr4 have been prepared by the two-step growth process as follows: (1) precipitation of nanometer-sized PbBr2 particles on substrates by vapor deposition and then (2) growth of (C8H17NH3)2PbBr4 films by exposing PbBr2 particles to C8H17NH3Br vapor. Atomic force microscope observations reveal that the substrate is fully covered with nanometer-sized rodlike precipitates. X-ray diffraction studies suggest that (C8H17NH3)2PbBr4 films are found to be microcrystalline form, single phase and highly oriented with the c-axis perpendicular to the substrate surface. (C8H17NH3)2PbBr4 films show a clear exciton absorption and free-exciton emission even at room temperature. At low temperatures below 40 K, the emission band separates into three bands at 3.07 (A-band), 3.14 (B-band) and 3.20 (C-band) eV, respectively. Both A- and C-bands correspond to the free-exciton emission with large binding energies. On the contrary, time-resolved PL spectra indicate that the B-band is attributed to phosphorescence formed by the intersystem crossing. 相似文献
7.
It is reported that optical selection rules still apply in light emission from the scanning tunneling microscope (STM). Linear polarization of isochromat light emitted from the tunneling gap between a STM tip made of tungsten (W) and a silicon (Si) sample with a (001) clean surface strongly depends on the bias voltage between tip and sample. The results show that pi* and sigma* surface states, for example, of the Si(001) sample contribute to emission of p- and s-polarized light, respectively, in accordance with optical selection rules. 相似文献
8.
A. Saito K. Takahashi Y. Takagi K. Hanai Y. Tanaka M. Akai-kasaya S. Shin T. Ishikawa M. Aono 《Surface science》2007,601(22):5294-5299
To solve difficulties of instability and inaccuracy in synchrotron radiation based scanning tunneling microscopy, a method to reduce noise was investigated. New insulator-coat tips were developed to shut out electrons coming from a wide area that damage the spatial resolution. By changing the exposed conductive area at the end of the insulator-coat tips, the effect of noise reduction was estimated. The tip with an exposure area of 50 nm in diameter was found to reduce noise effectively. Also a key discriminating condition was found to obtain the local signal, which is based on the modulation of the X-ray-induced tip current caused by excitation of the specific element. 相似文献
9.
10.
The quantitative evaluation on measurement of liver volume and the hepatic accumulation rate of the radioactive agent were studied with respect to body constitution, background activity and splenic consumption rate, using single photon emission computed tomography (SPECT). The optical cut-off level for liver volume determination was proved to be reasonable as 35%. The background less than 5% had no influence to their clinical estimation with the error of less than 1.6%. The estimation of liver volume was mostly influenced by the splenic activity. When the splenic activity was increased two times of the hepatic activity, the liver volume was determined as 4.2% larger. Calculated counts by SPECT was well correlated with the hepatic activity. This study proved that SPECT was useful for the quantitative evaluation of the liver volume and the hepatic accumulation rate. 相似文献