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2.
K. Yatsu T. Cho H. Higaki M. Ichimura K. Ishii Y. Ishimoto M. K. Islam A. Itakura I. Katanuma J. Kohagura Y. Nakashima T. Saito Y. Takemura Y. Tatematsu M. Yoshida M. Yoshikawa 《Czechoslovak Journal of Physics》2002,52(10):1143-1148
GAMMA 10 experiments have advanced in high density experiments after the last EPS Workshop where we reported high density
plasma production by using an ion cyclotron range of frequency heating at a high harmonic frequency and neutral beam injection
in the central cell. Recently a high density plasma was obtained with much improved reproducibility than before and without
degradation of diamagnetic signal. The high density plasma was attained by adjusting the spacing of the conducting plates
installed in the anchor transition regions. Dependencies of particle confinement time, ion energy confinement time and plasma
confining potential on plasma density were obtained for the first time in the high density region.
Presented at 5th Workshop “Role of Electric Fields in Plasma Confinement and Exhaust”, Montreus, Switzerland, June 23–24,
2002. 相似文献
3.
Akira Yanagisawa Prof. Dr. Takahiro Suzuki Takanori Koide Shogo Okitsu Takayoshi Arai Prof. Dr. 《化学:亚洲杂志》2008,3(10):1793-1800
A Barbier‐type regioselective propargylation of aldehydes and ketones with (3‐bromobut‐1‐ynyl)trimethylsilane has been achieved using reactive barium as a low‐valent metal in THF. Especially in the case of ketones, the corresponding homopropargylic alcohols form almost exclusively. In the reaction of α,β‐unsaturated carbonyl compounds, only 1,2‐adducts have been observed. This method is also applicable to propargylation of imines, and the corresponding homopropargylic amines are obtained regiospecifically in good yields with diastereomeric ratios of up to 87:13. 相似文献
4.
5.
Kosuke Morita Kouji Morimoto Daiya Kaji Yu Liang Zhao Atsushi Yoshida Toshimi Suda Akira Yoneda Tetsuya Ohnishi Hiromitsu Haba Eiji Ideguchi Hu Shan Xu Tao Zheng Hisaaki Kudo Keisuke Sueki Kenji Katori Isao Tanihata 《Acta Physica Hungarica A》2004,19(1-2):53-60
A gas-filled type of recoil separator for heavy element research was installed at an experimental hall of RIKEN Linear Accelerator facility to realize getting higher intensity of primary beam and long beam time. Performance of the separator was studied using target recoils and various nuclear reactions. The results show the high performance of the separator for heave element research. As an application of the GARIS, production and identification of an isotope of the 110th element 271[110] have been performed using the 208Pb(64Ni,1n)271[110] reaction. Three decay chains coincide well both in decay times and energies with the ones reported by the group of SHIP experiment at GSI, Germany. Our results provide a confirmation of the synthesis of an isotope 271[110] of element 110. 相似文献
6.
We measured the entire region of mesopic and photopic vision to determine the color zone covering the visual field with unique red, yellow, green, and blue hue components. Eight kinds of test stimuli in the natural color system (NCS) color notation system were used. These stimuli were presented at horizontal and vertical meridians, and at meridians inclined at 45° angles. The illuminance level was set at six levels: 0.01 lx-1000 lx. The evaluation method measured chromatic, white, and black components as well as the hue component of the stimuli. Results show that the color zone of the retina extended further into the periphery with increasing illuminance; the response of opponent colors y-b was shown to be greater than that of the opponent colors r-g. 相似文献
7.
Ryoichi Kizu Naoki Otsuki Yoshiko Kishida Akira Toriba Atsushi Mizokami Kerry L Burnstein Carolyn M Klinge Kazuichi Hayakawai 《Analytical sciences》2004,20(1):55-59
We developed a new mammalian cell-based luciferase reporter gene assay for androgenic and antiandrogenic activities of chemicals and environmental samples. Environmental samples usually have a complex matrix that may contain the constituents acting as androgen receptor (AR) agonists, AR antagonists or aryl hydrocarbon receptor (AhR) agonists. AhR agonists are known to elicit the antiandrogenic effect through cross-talk between AR and AhR signal transduction pathways. In this study, PC3/AR human prostate carcinoma cells were transiently transfected with a prostate-specific antigen (PSA) promoter-driven luciferase expression plasmid. The cells were treated with a test compound or an environmental sample for 24 h at 37 degrees C and then measured for luciferase activity. The luciferase activity was induced by dihydrotestosterone (DHT) in a concentration-dependent manner in a concentration range from 10 fM to 1 nM. R1881, a synthetic androgen receptor agonist, induced luciferase activity and its inductive effects was additive to that of DHT. The luciferase activity was not induced by cortisol, a glucocorticoid, progesterone, a progestin, and 17beta-estradiol, an estrogen in a concentration range of up to 1 microM. DHT-induced luciferase activity was reduced by bicalutamide and cyproterone acetate, AR antagonists, and also by benzo[a]pyrene, an aryl hydrocarbon receptor agonist, through AhR-mediated pathways. All of these findings indicate that the present assay system correctly responds to AR agonists, AR antagonists and AhR agonist and, therefore, it is a powerful tool for the sensitive and selective screening of chemicals and environmental samples for their androgenic and antiandrogenic activities. We developed the first assay system, in which the expression of luciferase was driven by the promoter of a prostate-specific antigen gene, a typical human androgen-regulated gene. 相似文献
8.
A large-volume (100 microl) injection-ETAAS with W-treated PG furnace combined with a phosphate modifier was applied to the determination of unpolluted levels of Cd in tap, snow and river-water samples. The limit of detection of 1.1 ng l(-1) was observed for a 4 w/v% NH4H2PO4 modifer. Matrix interference studies were tested for major ion species well found in fresh water. The direct determination of Cd in certified river water (12 +/- 2 ng l(-1)) was carried out and the observed value was in agreement with the certified one. The good recoveries of Cd added to real environmental water samples were also observed. This method was applied to the determination of Cd in unpolluted environmental water samples. 相似文献
9.
We studied the simultaneous quantitative analysis of biologically active substances, such as nicotinic acid, trigonelline, caffeine, qunolinic acid and tannic acid and pyrogallic acid, in several roasted coffees by an HPLC/diode-array system with a home-made sol-gel and ODS-2 columns. A simple method for simultaneous quantitative analysis of biologically active substances in the coffee brew became feasible by an HPLC/diode-array system with a sol-gel column at a single wavelength of 210 nm. The most efficient condition of the Rs value was above 1.05 when two sol-gel columns were connected. In addition, the elution behavior of nicotinic acid in brew extracted from commercially available coffee beans suggests the thermal decomposition process during roasting, and indicated the maximum value for full city roasted coffee. 相似文献
10.
The essential self-adjointness on a natural domain of the sharp-time Wick powers of the relativistic free field in two space-time dimension is proven. Other results on Wick powers are reviewed and discussed. 相似文献