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1.
Shunsuke Takagi Kei-ichi Watanabe 《Transactions of the American Mathematical Society》2004,356(10):3951-3961
Demailly, Ein and Lazarsfeld proved the subadditivity theorem for multiplier ideals on nonsingular varieties, which states the multiplier ideal of the product of ideals is contained in the product of the individual multiplier ideals. We prove that, in the two-dimensional case, the subadditivity theorem holds on log terminal singularities. However, in the higher dimensional case, we have several counterexamples. We consider the subadditivity theorem for monomial ideals on toric rings and construct a counterexample on a three-dimensional toric ring.
2.
Miyuki Harada Kentaro Aoyama Mitsukazu Ochi 《Journal of Polymer Science.Polymer Physics》2004,42(22):4044-4052
A liquid‐crystalline epoxy resin was cured at two different temperatures. The phases of the cured systems clearly showed isotropic and nematic polydomain structures, which depended on the curing temperature. The fracture toughness of the systems was measured, and the fracture mechanism was investigated with polarized IR measurements. The nematic polydomain structure system showed considerably higher fracture toughness than the isotropic structure. Moreover, both systems exhibited a reorientation of the network chains near the fracture surface during the fracture process, and the region of the network reorientation in the nematic polydomain structure system was larger than that in the isotropic structure system. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4044–4052, 2004 相似文献
3.
4.
Interface properties of BCN/GaN metal-insulator-semiconductor (MIS) structures are investigated by X-ray photoelectron spectroscopy (XPS) and capacitance versus voltage (C-V) characteristics measurements. The BCN/GaN samples are fabricated by in situ process consisting of plasma treatment and deposition of BCN film in the plasma-assisted chemical vapor deposition (PACVD) apparatus. XPS measurement shows that the oxide formation at the BCN/GaN interface is suppressed by nitrogen (N2) and hydrogen (H2) plasma treatment. The interface state density is estimated from C-V characteristics measured at 1 MHz using Terman method. The minimum interface state density appears from 0.2 to 0.7 eV below the conduction band edge of GaN. The minimum value of the interface state density is estimated to be 3.0 × 1010 eV−1 cm−2 for the BCN/GaN structure with mixed N2 and H2 plasma treatment for 25 min. Even after annealing at 430 °C for 10 min, the interface state density as low as 6.0 × 1010 eV−1 cm−2 is maintained. 相似文献
5.
G. M. Luke L. P. Le B. J. Sternlieb Y. J. Uemura J. H. Brewer R. Kadono R. F. Kiefl S. R. Kreitzman T. M. Riseman C. E. Stronach M. Davis S. Uchida H. Takagi Y. Tokura Y. Hidaka T. Murakami E. A. Early J. T. Markert M. B. Maple C. L. Seaman 《Hyperfine Interactions》1991,63(1-4):311-317
We report muon spin relaxation/rotation measurements on sintered powder samples of Nd2−x
Ce
x
CuO4−y
and a large single crystal of Nd2CuO4−y
. We find an electronic phase diagram which is quite similar to that of hole-doped superconductors such as La2−x
Sr
x
CuO4−y
, although the doping of electrons into the system is less efficient in destroying the static moments on the copper spins.
Static magnetic order in Nd2CuO4−y
appears below about 250 K, and two spin reorientations are seen atT=75 K andT=35 K. Measurements of the magnetic field penetration depth have been unsuccessful due to the rare-earth paramagnetism of
these materials. 相似文献
6.
7.
8.
Porcine kidney extracts (PKE) possess colony-promoting activity (CPA) which stimulates primitive hematopoietic cells in the presence of granulocyte/macrophage colony-stimulating factor (GM-CSF), but PKE itself does not stimulate colony formation on murine bone marrow cells. We have compared the CPA of PKE with that of recombinant cytokines or CSFs such as interleukin-1 alpha (IL-1 alpha), IL-3, IL-6, granulocyte colony-stimulating factor (G-CSF), GM-CSF and macrophage colony-stimulating factor (CSF-1). All of these factors were less potent than PKE. Furthermore, the combinations of IL-1 alpha or PKE with G-CSF, GM-CSF, IL-3 or IL-6 were examined in the presence of one of these factors such as CSF. It is found that PKE acts synergistically with G-CSF, GM-CSF, IL-3 and IL-6, showing enhancement ratios of 10, 2.5, 4.2 and 30, respectively. The combination of IL-1 alpha resulted in poor colony formation in contrast with those of PKE, except for CSF-1. These results suggest that the CPA of the factor(s) in PKE differ from the cytokines and CSFs tested in this study, and is significantly affected by various types of CSF. 相似文献
9.
Tetrakis-acridinyl peptide 1 assuming a right-handed helical stacked conformation of the acridinyl units can bind to DNA duplex with a very high affinity of 10(8) (M-bp)(-1) even at a high salt concentration of 0.2 M NaCl, irrespective of the base composition. Peptide 1 gave rise to 1600-times enhancement of its fluorescence upon binding to an AT polymer due to the collapse of this stacked structure, but the fluorescence is not enhanced with a GC polymer, though the binding constants of 1 for both polymers were the same. 相似文献
10.
A. Nakaoka H. Yokoyama M. Fukushima S. Takagi 《Journal of Radioanalytical and Nuclear Chemistry》1980,56(1-2):13-24
A rapid and precise method of determining radiocesium corresponding to 5 mrem/y, the Japan AEC's guideline, was proposed.
The development and practical performance of cesium-selective resin and the determination method was described in this paper.
The resin was prepared by the formation of ammonium molybdophosphate in the structure of Amberlite XAD-7 resin. It took only
3 hours to carry out all the procedures the authors proposed. This value represents 1/10∼1/2 of the time of conventional method.
The concentration of137Cs and134Cs in sea water was determined to be 0.13∼0.16 pCi/1 and less than 7.1·10−2 pCi/1, respectively. 相似文献