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101.
Yasuhiro Masuda Koichiro Asahi Kichiji Hatanaka Sun-Chan Jeong Shinsuke Kawasaki Ryohei Matsumiya Kensaku Matsuta Mototsugu Mihara Yutaka Watanabe 《Physics letters. A》2012
A neutron EDM measurement with a comagnetometer is discussed. For magnetometry, polarized xenon atoms are injected into a cylindrical cell where a cylindrically symmetric magnetic field and an electric field are applied for the EDM measurement. The geometric phase effect (GPE), which originates from particle motion in a magnetic field gradient, is analyzed in terms of the Dyson series. The motion of the xenon atom is largely suppressed because of a small mean free path. The field gradient is controlled by means of NMR measurements, where the false effect of Earth?s rotation is removed. As a result, the GPE is reduced below 10−28e cm. 相似文献
102.
Masuda Y Hatanaka K Jeong SC Kawasaki S Matsumiya R Matsuta K Mihara M Watanabe Y 《Physical review letters》2012,108(13):134801
For the production of high-density ultracold neutrons (UCNs), we placed 0.8 K superfluid helium in a cold neutron moderator. We resolved previous heat-load problems in the spallation neutron source that were particularly serious below 1 K. With a proton-beam power of 400 MeV×1 μA, a UCN production rate of 4 UCN cm(-3) s(-1) at the maximum UCN energy of E(c)=210 neV and a storage lifetime of 81 s were obtained. A cryogenic test showed that the production rate can be increased by a factor of 10 with the same storage lifetime by increasing the proton-beam power as well as (3)He pumping speed. 相似文献
103.
Mridul Kanti Mandal Kentaro Yoshimura Lee Chuin Chen Zhan Yu Tadao Nakazawa Ryohei Katoh Hideki Fujii Sen Takeda Hiroshi Nonami Kenzo Hiraoka 《Journal of the American Society for Mass Spectrometry》2012,23(11):2043-2047
We have examined several combinations of solvents with the aim of optimizing the ionization conditions for molecular diagnosis of malignant tumours by PESI-MS. Although the best conditions may depend on the actual species in the sample, the optimal conditions for renal cell carcinoma (RCC) were achieved by using alcohols. PESI-MS successfully delineated the differential expression of phospholipids (PCs) and triacylglycerols (TAGs) in noncancerous and RCC tissues by using these solvent systems. This study paves the way for the application of PESI-MS in medical samples. 相似文献
104.
R Kobayashi K Hanaya M Shoji K Umezawa T Sugai 《Chemical & pharmaceutical bulletin》2012,60(9):1220-1223
In order to synthesize the potent nuclear factor (NF)-κB inhibitor, (2S,3S,4S)-dehydroxymethylepoxyquinomycin (DHMEQ), in a large scale, a new route for its corresponding racemic precursor, dihexanoyl (2R*,3R*,4R*)-DHMEQ, was developed. By employing both hydroquinone and benzoquinone intermediates, the total yield, reproducibility, and synthetic steps were improved and the synthetic cost was reduced. 相似文献
105.
The kinetics of the flattening of surface corrugations of float glasses were investigated in dry nitrogen at 610 to 670°C. The amplitude of the sinusoidal surface profile decayed exponentially with time while its wavelength remained constant. The dependence of decay rate on wavelength indicated that the process is controlled by the viscous flow. From the obtained rate constant the viscosity was calculated using the surface energy value determined independently by the zero-creep method. The viscosity thus obtained reflects the mass transport property in the vicinity of the glass surface. It was several times larger than that determined by the fibre elongation or intrusion method which should reflect the bulk properties. No difference in the decay rate was observed on both the surfaces of float glass of which only one side had been exposed to molten tin during the glass manufacturing process. 相似文献
106.
Dose-dependent inhibition of ultrasound-induced cell killing and free radical production by carbon dioxide 总被引:9,自引:0,他引:9
Previous studies have shown that if a solution for cell suspension is saturated with CO(2), ultrasound-induced in vitro cell killing and free-radical production are inhibited. However, the dose dependency of this observation has not been explored. Here, we used NaHCO(3) and HCl to produce a predictable concentration of CO(2) within the culture medium. Using 1 MHz continuous wave 4 W/cm(2) ultrasound, we sonicated U937 cells suspension for 1 min at 37 degrees C with CO(2) at different concentrations. At 2 mM, reduced cell killing was observed that further decreased with increasing CO(2) concentration until 100% protection was attained at 20 mM. Ultrasound-induced free-radical production was significantly decreased at 1 mM and became undetectable at 2 mM CO(2). This finding shows that CO(2)-mediated inhibition is concentration dependent and that the threshold for free-radical production is one order of magnitude higher than the threshold for cell killing induced by ultrasound. In addition, it also cautions researchers when adding acids and acid-based agents to a culture medium, which almost always contains NaHCO(3), in experiments related to the bioeffects of ultrasound. 相似文献
107.
X-ray spectra scattered at 90° by acrylic resin plates of various thicknesses are measured. The intensity and polarization of Compton-scattered X-rays are estimated from the spectra. As the thickness of the slab increases, the intensity increases but the polarization decreases. The optimal thickness for a polarized X-ray fluorescence spectrometer is determined, which provides both high intensity and high polarization. 相似文献
108.
109.
An empirical formulation is presented to predict the stereochemistry of major osmylation products of allylic alcohols and their derivatives. 相似文献
110.
Thermoosmosis through anion-exchange membranes was measured for 10-3 to 2 mol/kg of aqueous KCl, LiCl, and NH4Cl and for 10-3 to 3 x 10-1 mol/kg of aqueous KIO3 and K2SO4. For all electrolytes used the direction of thermoosmosis was from the cold side to the hot side over the whole range of concentrations. For KCl and LiCl the experimental results were analyzed with an extension of a previously published theory, using additional data for transport numbers of ions in membranes and for electroosmosis. The agreement between theory and experiment is satisfactory. The absolute value of thermoosmosis for KIO3 is larger than that for other electrolytes because the pore volume fraction of the membrane for KIO3 is larger than that for the other electrolytes. 相似文献