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101.
We study population dynamics of a trapped spin-1 Bose gas above the Bose-Einstein transition temperature. Starting from the semiclassical kinetic equation for a spin-1 gas, we derive coupled rate equations for the populations of internal states. Solving the rate equations, we study the dynamical evolution of spin populations. We also estimate the characteristic timescale in which the system reaches equilibrium. Finally, we briefly discuss the extension of the theory to Bose-condensed phase below the Bose-Einstein transition temperature, and discuss the static equilibrium condition for the spin-1 system. 相似文献
102.
Endo T. Murayama Y. Sakamoto Y. Sakuraba T. Shiota F. 《IEEE transactions on instrumentation and measurement》1989,38(2):229-232
A series of systems composed of cryogenic devices such as a Josephson potentiometer and a cryogenic current comparator, developed to precisely measure a current with any value up to 1 A, is proposed. These systems will be used to measure the injected electrical energy with an uncertainty of the order of 0.01 p.p.m. or less in the absolute measurement of the magnetic flux quantum by superconducting magnetic levitation. Some preliminary experiments are described 相似文献
103.
Some tetracycline (TC) antibiotics, including TC and anhydrotetracycline, have been found to enhance specific binding of low
density lipoprotein (LDL) to both LDL receptor-positive and-negative cells at relatively higher concentrations. When incubated
at 37°C, the ability of LDL receptor-negative human fibroblasts to bind 125I-LDL was increased from<2 to 45 ng/mg by 170 μM TC. In normal human fibroblasts and Hep G2 cells, 125I-LDL binding was elevated 1.4- to 2-fold by 113 μM TC. The 125I-LDL binding in the presence of TC was diminished by both heparin and EDTA. The enhancement by TC was not observed when 125I-LDL binding was assayed at 4°C. TC enhanced LDL binding to paraformaldehyde-fixed Hep G2 cells, excluding LDL receptor induction
in the mechanism. These results demonstrated that TC enhanced cellular LDL binding through a process not involving functional
LDL receptors. 相似文献
104.
105.
Sho Kataoka Takuji Yamamoto Yuki Inagi Akira Endo Masaru Nakaiwa Takao Ohmori 《Carbon》2008,46(10):1358-1360
Mesoporous carbon thin films with ordered structures were prepared by using resorcinol-surfactant self-assembly. A mixture of resorcinol, surfactant, and ethanol coated on silicon substrates was exposed to formaldehyde vapor as a cross-linking agent to form structured resorcinol/formaldehyde resin films. The films were then carbonized at 800 °C in an inert atmosphere to remove the surfactant and to obtain structured carbon materials. With this vapor infiltration method, thin films with several structures were obtained from the same precursor solution by employing different vapor infiltration temperatures. The results were interpreted from the transformation of the self-assembly during the vapor infiltration process. 相似文献
106.
Mono‐ and bifunctional six‐membered cyclic carbonates synthesized by diphenyl carbonate toward networked polycarbonate films
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The synthesis of six‐membered cyclic carbonates from diols utilizing less toxic and easily‐handled diphenyl carbonate (DPC) is carried out based on the reactivity and selectivity at different conditions. Commercially‐available neopentylglycol (NPG) or di(trimethylolproapane) (DTMP) react effectively with DPC at 140°C and converted to their corresponding monofunctional NPG‐carbonate (NPGC) or bifunctional DTMPC‐carboante (DTMPC), respectively. The selectivity of these carbonates changes depending on a feed ratio of DPC and these diols. After a NPG/DPC mixture with the DPC/NPG feed ratio of 4 was heated at 140°C for 48 h, the NPGC is isolated with a yield of 74%. A 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU)‐catalyzed ring‐opening polymerization (ROP) of NPGC with DTMPC can form effectively networked structures. By only drying of THF solutions containing NPGC, DTMPC, and a catalytic amount of DBU at 60°C for 12 h, the ROP efficiently proceeds and networked polycarbonate films with well transparency and flexibility are easily obtained. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41956. 相似文献
107.
A. Sakaguchi K. Kawai T. Imanaka S. Endo M. Yamamoto 《The Science of the total environment》2010,408(22):5392-5398
The first results on the feasibility of using 236U to reconstruct the level and spatial distribution of close-in fallout deposition from the Hiroshima A-bomb are reported, coupled with the use of global fallout 137Cs and 239 + 240Pu. The results for global fallout 236U in soil samples (0-30 cm) from Ishikawa prefecture showed that the deposition density of 236U from the global fallout can be accurately evaluated using AMS. All deposited 236U, 137Cs and 239 + 240Pu appeared to have been recovered using 30-cm cores. It was also noted from the depth profiles for 236U/239 + 240Pu and 236U/137Cs ratios that the downward behavior of 236U in the soil was apparently similar to that of 239 + 240Pu, while the 137Cs was liable to be retained in upper layers compared with 236U and 239 + 240Pu. The accumulated levels were 1.78 × 1013 atoms m− 2 for 236U, 4340 Bq m− 2 for 137Cs and 141 Bq m− 2 for 239 + 240Pu. The ratios of 236U/137Cs and 236U/239 + 240Pu were (4.10 ± 0.12) × 109 and (1.26 ± 0.04) × 1011 atoms Bq− 1, respectively. Results of 236U, 137Cs and 239 + 240Pu measurements for the seven soil cores (0-30 cm) from Hiroshima were discussed on the basis of ratios of 236U/137Cs and 236U/239 + 240Pu by comparing with those from the background area in Ishikawa, indicating that the global fallout dominates the current level of 236U accumulation in soil in the Black-rain area around Hiroshima after the Hiroshima bomb, and the contribution of the close-in fallout 236U produced by the Hiroshima A-bomb seems difficult to observe. 相似文献
108.
Kohei Urasaki Ken-ichiro Endo Tomoki Takahiro Ryuji Kikuchi Toshinori Kojima Shigeo Satokawa 《Topics in Catalysis》2010,53(7-10):707-711
Selective methanation of CO in the reformate gas (CO/CO2/H2/H2O = 0.175/17.9/70.9/11.1) proceeded over Ru catalysts supported on metal oxides and zeolites. CO was selectively methanated at wide temperature ranges (200–275 °C) over Ru/γ-Al2O3, Ru/TiO2 Ru/H-Y and Ru/H-beta catalysts. Higher Ru contents in Ru/γ-Al2O3 improved the selective CO methanation rate. 相似文献
109.
The distribution properties of magnetic force and surface temperature on a curved conductor have been investigated. The results reveal that those distributions are nonuniform along the conductor. The maximum value is located at the vertex of the curved part and is influenced by the curved radius and the curved angle 相似文献
110.
Raayaa Wananuruksawong Yutaka Shinoda Takashi Akatsu Fumihiro Wakai 《International Journal of Applied Ceramic Technology》2013,10(5):756-763
Creep behavior of Si3N4 polycrystals containing Y2O3‐MgO‐SiO2 glass phase (with and without Calcium oxide [CaO] additive) was studied by compression tests between 1500 and 1700°C. We studied the effect of CaO additive on flow stress, microstructural evolutions, and thermal stability of the intergranular glass phase during deformation. While the addition of CaO did not affect grain size, the flow stress decreased with the amount of CaO. This result suggested that the addition of CaO reduced the viscosity of intergranular glass phase. The addition of CaO further improved the thermal stability of the glass phase by suppressing the evaporation at elevated temperatures. 相似文献