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91.
Inelastic scattering of 80 MeV deuterons from 58Ni and 120Sn is analyzed in terms of an adiabatic coupled-channels Born approximation (ACCBA) method. The ACCBA method is a practical means to treat deuteron plus nucleus as a three-body system. Inclusion of the breakup modes significantly reduces the inelastic cross section. The significance of considering both the s-wave and d-wave breakup modes is pointed out.  相似文献   
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超声波信号渡越时间参数法测量空气中温度分布   总被引:6,自引:1,他引:5       下载免费PDF全文
超声波已成功在医疗、化工和无损探伤等领域得到广泛的应用。根据超声波在空气中的传播速度会随着温度改变而改变这一特点,本文把空气中的温度场作为研究对象,利用超声波信号在空气中的渡越时间参数TOF(Time of Flight)来对空气中的温度分布情况进行超声波CT画像的重建。  相似文献   
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The molecular conformation and melting behavior of triblock position isomers H(CH(2))(k)(OCH(2)CH(2))(4)O(CH(2))(12)(-)(k)H (abbreviated as C(k)E(4)C(12)(-)(k)) with k = 6-11 have been studied by infrared spectroscopy and differential scanning calorimetry (DSC), with focus on the effect of the position of an oligo(oxyethylene) block in the molecule. The analysis of infrared spectra has revealed that the stable molecular form changes from a fully planar structure (gamma form) to a planar/helical/planar structure (beta form) with a change of the position of the tetrakis(oxyethylene) block from the center to the end of the molecule. The DSC measurements have shown that the melting points of the gamma-form solid decrease and the melting points of the beta-form solid increase with a shift of the tetrakis(oxyethylene) block toward the terminal of the molecule. The stabilities of the two molecular forms change over between k = 8 and 9. C(8)E(4)C(4) and C(9)E(4)C(3) exhibit contrasting conformational behavior with temperature; when the temperature is increased, the metastable beta form of C(8)E(4)C(4) transforms into the stable gamma form, while the metastable gamma form of C(9)E(4)C(3) transforms into the stable beta form. The metastable gamma form with a planar oligo(oxyethylene) block is a new finding in the present work. The experimental results of the stabilities of molecular forms are explained by the relative stabilities of partial crystal lattices formed by the alkyl and oligo(oxyethylene) blocks.  相似文献   
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Glucuronidase-catalyzed transglycosylation was examined by using 4-nitrophenyl beta-D-glucuronide (D-GlcA-O-pNP) as the glycosyl donor; when pNP 6-O-sulfo-beta-D-gluco- and D-galacto-pyranosides were used as the acceptors, a bovine enzyme was found to construct beta-D-GlcA-(1-3)-linkages with the 6-O-sulfo-sugars in both a site- and beta-selective way.  相似文献   
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We introduce the notion of semi-tilting modules and show that the class of basic semi-tilting modules is closed under mutation. Using this, we provide a partial answer to the Wakamatsu tilting conjecture. Also, we define a partial order on the set of equivalence classes of semi-tilting modules and show that this order is closely related to mutation for semi-tilting modules.  相似文献   
100.
Shockley partial dislocations in 4H-SiC were observed using monochromatic synchrotron X-ray topography with a grazing-incidence Bragg-case geometry, that is, Berg–Barrett topography. The contrast of partial dislocations at the edges of Shockley-type stacking faults is discussed in terms of whether they have C- or Si-core edge components, or screw components. The dissociated state of basal-plane dislocation is discussed on a basis of the stacking sequence for basal-planes in the 4H-SiC crystal structure. It is expected that the results obtained in this study will be useful for characterizing Shockley-type stacking faults in Berg–Barrett topography.  相似文献   
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