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941.
Honda Y Kubo K Anderson S Araki S Bane K Brachmann A Frisch J Fukuda M Hasegawa K Hayano H Hendrickson L Higashi Y Higo T Hirano K Hirose T Iida K Imai T Inoue Y Karataev P Kuriki M Kuroda R Kuroda S Luo X McCormick D Matsuda M Muto T Nakajima K Naito T Nelson J Nomura M Ohashi A Omori T Okugi T Ross M Sakai H Sakai I Sasao N Smith S Suzuki T Takano M Taniguchi T Terunuma N Turner J Toge N Urakawa J Vogel V Woodley M Wolski A Yamazaki I Yamazaki Y Yocky G Young A Zimmermann F 《Physical review letters》2004,92(5):054802
For high luminosity in electron-positron linear colliders, it is essential to generate low vertical emittance beams. We report on the smallest vertical emittance achieved in single-bunch-mode operation of the Accelerator Test Facility, which satisfies the requirement of the x-band linear collider. The emittances were measured with a laser-wire beam-profile monitor installed in the damping ring. The bunch length and the momentum spread of the beam were also recorded under the same conditions. The smallest vertical rms emittance measured at low intensity is 4 pm at a beam energy of 1.3 GeV, which corresponds to the normalized emittance of 1.0x1.0(-8) m. It increases by a factor of 1.5 for a bunch intensity of 10(10) electrons. The measured data agreed to the calculation of intrabeam scattering within much better than a factor of 2. 相似文献
942.
A simple and rapid method is described for the determination of iron in serum by atomic absorption spectrometry with a graphite furnace atomiser. The serum is diluted 40 times with water, and injected into the graphite tube. Optimal conditions are established, and interferences from proteins and salts eliminated. Since the procedure requires no sample pretreatment such as protein precipitation or wet digestion, contamination and losses by co-precipitation are excluded. The method can determine any species of iron in serum. 相似文献
943.
Nickel-catalyzed cross-coupling of Grignard reagents with aryl (poly)fluorides or (poly)chlorides can be achieved efficiently in the presence of a new triarylphosphine ligand bearing a nearby hydroxy group. The high reactivity and the unique chemoselectivity (ArF > ArOTf > ArSR) of the catalysis have been attributed to synergy of nickel and magnesium atoms preorganized on the ligand, as has been surmised on the basis of theoretical modeling of the reaction mechanism. 相似文献
944.
945.
[structure: see text] A cyclobarbital-selective molecularly imprinted polymer was prepared using a fluorescent functional monomer, 2-acrylamidoquinoline. This monomer was designed to increase in fluorescence intensity upon hydrogen bonding to the cyclobarbital guest. The resultant imprinted polymers exhibited the enhancement of the fluorescence intensity when cyclobarbital was bound. Our results show that this fluorescent responsive imprinting method could be useful in the development of sensors for quantification of nonfluorescent compounds. 相似文献
946.
Fujita T Ide S Kamada Y Suzuki T Oikawa T Takeji S Sakamoto Y Koide Y Isayama A Hatae T Kubo H Higashijima S Naito O Shirai H Fukuda T 《Physical review letters》2001,87(8):085001
A quasisteady reversed shear plasma with a large bootstrap current fraction ( approximately 80%) has been obtained for the first time in the JT-60U tokamak. The shrinkage of reversed shear region was suppressed by the bootstrap current peaked at the internal transport barrier (ITB) layer and the ITBs at a large radius were sustained, which, by combination with an H-mode edge pedestal, resulted in a high confinement or 2.2 times the H-mode scaling for 6 times energy confinement time or 2.7 s. Furthermore, a full noninductive current drive was obtained by the bootstrap current and the beam driven current. 相似文献
947.
A simple analytical system using light scattering (LS) method has been developed to determine phase transition temperatures of liquid crystals (LCs). Intensity changes of the transmission light through a sample were measured as a function of temperature. All LCs and non-LCs showed appreciable changes in the transmission intensity at the phase transition temperature. The transition temperatures determined by the LS method were identical to those by differential scanning calorimetry (DSC). 相似文献
948.
Ishii H Yamaguchi K Seki H Sakamoto S Tozuka Y Oguchi T Yamamoto K 《Chemical & pharmaceutical bulletin》2002,50(8):1022-1027
The title compound, PNU-97018 [systemic name: 2-butyl-3,6,7,8,9,11-hexahydro-6,9-dimethyl-3-([2'-(2H-tetrazol-5-yl)[1,1'-biphenyl]-4-yl]methyl)-6,9-ethano-4H-imidazo[4,5-d]-pyridazino[1,2-a]pyridazin-4-one] is a newly developed angiotensin II receptor antagonist. The compound and its methanolate and ethanolate were characterized by X-ray crystallography and thermal analysis. The methanolate and ethanolate crystals have an almost identical molecular conformation and crystal packing. In both alcoholates, each alcohol molecule is fixed to the compound with a molar ratio of 1 : 1 by a hydrogen bond between the hydroxyl group of the alcohol molecule and the tetrazole group of the compound. The hydroxyl group of each alcohol molecule further links with the imidazole ring of the neighboring compound by hydrogen bond to form a hydrogen-bond network in both alcoholates. A tunnel-like structure that includes alcohol molecules is formed in each alcoholate. The ansolvate crystal showed completely different thermal and X-ray crystallographic characteristics from the alcoholates, where the compound molecules were directly linked by hydrogen bonds between the tetrazole group of a molecule and the imidazole ring of the neighboring molecule. The position of the hydrogen atom in the tetrazole ring was different between the ansolvate and alcoholates. Unlike alcoholates, a layer structure stacked on the b-c plane was observed in the ansolvate crystal. It was concluded that the molecular conformation and the arrangement of the compound molecules were largely different between ansolvate and alcoholate crystals. 相似文献
949.
Taguchi H Miyashita H Tsubouchi A Takeda T 《Chemical communications (Cambridge, England)》2002,(19):2218-2219
1,4-Silyl migration from sp2 carbon to carbonyl oxygen proceeded by the treatment of (Z)-beta-trimethylsilyl-alpha,beta-unsaturated ketones with copper(I) tert-alkoxide to afford vinylmetal species, which reacted with allylic halides to produce enol trimethylsilyl ethers of beta-alk-2-enyl-alpha,beta-unsaturated ketones with complete retention of configuration. 相似文献
950.