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51.
52.
The traditional use of LIBOR futures prices to obtain surrogates for the Eurodollar forward rates is proved to yield a systematic bias in the pricing of Eurodollar swaps when one assumes that the yield curve is well described by the Heath-Jarrow-Morton model. The resulting theoretical inequality is consistent with the empirical observations of Burghardt and Hoskins (1995), and it provide a theoretical basis for price anomalies that are suggested by more recent empirical data. 相似文献
53.
直线加速器驻波腔中的瞬态束流负载效应 总被引:1,自引:0,他引:1
在高能加速器中, 随着单个束团和束团串中电荷量的提高, 当粒子束穿过加速腔的时候, 感应出的瞬态束流负载电压也越来越高. 但是, 在通常分析束流负载的时候, 往往对稳态束流负载研究的比较多, 而对瞬态束流负载的研究要相对少一些. 本文首先对束流负载的瞬态特性和束团穿过加速腔时高频源所看到谐振腔谐振频率的变化方式进行了分析, 然后又对两种情况下谐振腔的最优失谐条件进行了讨论, 并给出了相应的解析公式. 在第1种情况下, 当粒子束穿过加速腔的时候, 谐振腔的自然谐振频率能够及时地得到调节, 从而使高频源的电流与谐振腔的腔压同相, 以提高高频源的效率; 在第2种情况下, 当粒子束穿过加速腔的时候, 谐振腔的自然谐振频率保持不变, 不能被调节. 最后, 还对BEPCⅡ现有预注入器的预聚束腔、BEPCⅡ未来预注入器的两个次谐波聚束腔中的瞬态束流负载效应进行了分析. 相似文献
54.
Tzong‐Ming Wu Shih‐Hsiang Lin 《Journal of polymer science. Part A, Polymer chemistry》2006,44(21):6449-6457
Size‐controllable polypyrrole (PPy)/multiwalled carbon nanotube (MWCNT) composites have been synthesized by in situ chemical oxidation polymerization directed by various concentrations of cationic surfactant cetyltrimethylammonium bromide (CTAB). Raman spectra, FTIR, SEM, and TEM were used to characterize their structure and morphology. These results showed that the composites are core (MWCNT)–shell (PPy) tubular structures with the thickness of the PPy layer in the range of 20–40 nm, depending on the concentration of CTAB. Raman and FTIR spectra of the composites are almost identical to those of PPy alone. The electrical conductivities of these composites are 1–2 orders of magnitude higher than those of PPy without MWCNTs. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6449–6457, 2006 相似文献
55.
M.M. El-Nahass M.A.M. Seyam H.E.A. El-Sayed A.M. Abd El-Barry 《Applied Surface Science》2006,252(18):6218-6227
Thin films of samples of the glassy SxSe100−x system with 0 ≤ x ≤ 7.28 have been prepared by thermal evaporation technique at room temperature (300 K). X-ray investigations show that the structure of pure selenium (Se) does change seriously by the addition of small amount of sulphur S ≤7.28%. The lattice parameters were determined as a function of sulphur content. Results of differential thermal analysis (DTA) of the glassy compositions of the system SxSe100−x were discussed. The characteristic temperatures (Tg, Tc and Tm) were evaluated. Dark electrical resistivities, ρ, of SxSe100−x thin films with different thicknesses from 100 to 500 nm, were measured in the temperature range from 300 to 423 K. Two distinct linear parts with different activation energies were observed. The variation of electrical resistivity of examined compositions has been discussed as a function of the film thickness, temperature and the sulphur content. The application of Mott model for the phonon assisted hopping of small polarons gave the same two activation energies obtained from the resistivity temperature calculations. 相似文献
56.
J. Huňady M. ČerníkE.J. Hilinski M. PredmerskýA. Magurová 《Journal of magnetism and magnetic materials》2006
This paper discusses the influence of chemical composition on the final electromagnetic properties in higher permeability material. Furthermore, the effect of the hot rolling practice and the end of austenite transformation temperature range on the hot band microstructure is described. The magnetic polarization J5000 better than 1.7 T, using hot rolling conditions 40 mm transfer bar thickness, finish mill entry temperature 1000 °C, and finishing temperature 800–840 °C and after decarburization heat treatment and grain growth treatment, was obtained. 相似文献
57.
外电场下光聚合反应动力学的表征方法李从武,潘昂上海材料研究所,上海200082)关键词光聚合反应、液晶、外电场、动力学、表征近年来,液晶单体在外场(电场、磁场和剪切力)下在位光聚合反应的研究工作受到了很大的关注[’,ZI.众所周知,热致型侧链高分子液... 相似文献
58.
59.
Ni-SDC固体氧化物燃料电池阳极的合成和性质 总被引:4,自引:0,他引:4
采用柠檬酸-硝酸盐溶胶-凝胶低温自蔓延燃烧法制备氧化镍(NiO)粉末和Ce0.8Sm0.2O1.9(SDC)粉末,并将NiO与SDC按不同质量比和不同制备工艺制备了固体氧化物燃料电池(SOFC)的阳极前身。再用自组装的还原装置将其在820℃经2.5h还原后,采用四端子法测量其电导率值。分析了阳极片电导率与阳极片微结构、Ni的质量百分数、混合研磨时间及烧结温度之间的关系。结果显示,阳极片的电导率强烈依赖于镍含量和制备工艺。 相似文献
60.
Investigations on Electronically Conducting Oxide Systems. XVI. Solid Solutions and Conductivity in the System MgTi2O5? Ti3O5 Solid solution formation is reported for the system Mg1–xTi2–xIVTi2xIIIO5. With increasing x there is at room temperature a transition from the orthorhombic pseudobrookite structure to the monoclinic low-temperature modification of Ti3O5. The X-ray diffraction pattern results are supported by DSC measurements, electrical and magnetic investigations. The tendency of Ti? Ti pair formation in the low-temperature Ti3O5 structure is accompanied by a drop of the activation energy for electrical conductivity and a decreasing susceptibility at high TiIII concentrations. 相似文献