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71.
Akiko Ohno Nana Kawasaki Kiyoshi Fukuhara Haruhiro Okuda Teruhide Yamaguchi 《Magnetic resonance in chemistry : MRC》2010,48(2):168-172
Complete NMR analysis of oxytocin (OXT) in phosphate buffer was elucidated by one‐dimensional (1D)‐ and two‐dimensional (2D)‐NMR techniques, which involve the assignment of peptide amide NH protons and carbamoyl NH2 protons. The 1H? 15N correlation of seven amide NH protons and three carbamoyl NH2 protons were also shown by HSQC NMR of OXT without 15N enrichment. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Crystallographic tilt and Surface topography of InGaAs and InAlAs based metamorphic buffer structures on GaAs (001) substrate grown by molecular beam epitaxy (MBE) under varying growth conditions have been investigated. Compressively strained metamorphic buffer layers show anisotropic strain relaxation. A novel tilt determination technique based on X‐ray diffraction has been developed which can separate the effect of anisotropic strain. Tilt has been found to depend on compositional grading scheme, growth temperature and surface irregularities. Samples having random surfaces show smaller tilt than that of samples showing regular cross‐hatch. At higher growth temperature, reduction of tilt has been observed and correlated with thermal activation of otherwise inactive slip systems at low temperature. At low temperature and also for continuously graded samples, reduction of tilt has been observed and correlated with the slower relaxation that provide the opportunity for all the slip systems to participate and compete. 相似文献
74.
The oxidative coupling reaction between hydroquinone or catechols and various sodium benzenesulfinates was investigated using the laccase from Trametes versicolor, in the presence of O2 in a phosphate buffer solution at room temperature to afford sulfonyl benzenediols in 75–95% yield. 相似文献
75.
根据鱼雷对舰船毁伤的特点,建立了多介质水下爆炸数值模型,提出了交界面处理及广义光滑长度计算方法,编制了多介质水下爆炸计算程序,并对水下爆炸空气隔层衰减冲击波的性能进行了定量分析。结果表明:无论是接触爆炸还是非接触爆炸,空气隔层均可有效衰减冲击波,并且接触爆炸中空气隔层衰减冲击波的效果更好,最大可使冲击压力峰值降低约55%;空气隔层厚度与爆炸厚度之比为1时便可达到较好的衰减冲击波效果,继续增加空气隔层厚度对衰减冲击波效果影响不大。研究结果可为舰船结构防护及防雷舱的结构设计提供参考。 相似文献
76.
I. Usman Z. Buthelezi J. Carter G.R.J. Cooper R.W. Fearick S.V. Förtsch H. Fujita Y. Fujita Y. Kalmykov P. von Neumann-Cosel R. Neveling P. Papakonstantinou A. Richter R. Roth A. Shevchenko E. Sideras-Haddad F.D. Smit 《Physics letters. [Part B]》2011
The fragmentation of the Isoscalar Giant Quadrupole Resonance (ISGQR) in 40Ca has been investigated in high energy-resolution experiments using proton inelastic scattering at Ep=200 MeV. Fine structure is observed in the region of the ISGQR and its characteristic energy scales are extracted from the experimental data by means of a wavelet analysis. The experimental scales are well described by Random Phase Approximation (RPA) and second-RPA calculations with an effective interaction derived from a realistic nucleon–nucleon interaction by the Unitary Correlation Operator Method (UCOM). In these results characteristic scales are already present at the mean-field level pointing to their origination in Landau damping, in contrast to the findings in heavier nuclei and also to SRPA calculations for 40Ca based on phenomenological effective interactions, where fine structure is explained by the coupling to two-particle–two-hole (2p–2h) states. 相似文献
77.
The cross sections for (n,x) reactions with Ge isotopes were measured at (d–t) neutron energies around 14 MeV with the activation technique using metal discs of natural composition. Calculations of detector efficiency, incident neutron spectrum and correction factors were performed with the Monte Carlo technique (MCNP4C code). Cross sections data are presented for 70Ge(n,2n)69Ge, 74Ge(n,α)71mZn, 76Ge(n,2n)75(m + g)Ge, 70Ge(n,p)70Ga and 72Ge(n,2n)71gGe reactions. The cross section results for 72Ge(n,2n)71gGe reaction were reported for the first time. Some other cross sections were obtained with higher precision, including the 70Ge(n,p)70Ga reaction. Theoretical calculations of excitation functions were performed with the TALYS-1.0 code and compared with the experimental cross section values. Data were included in the EXFOR database. 相似文献
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We study various properties of a nonperturbative partition function which can be associated with any spectral curve. When the spectral curve arises from a matrix model, this nonperturbative partition function is given by a sum of matrix integrals over all possible filling fractions, and includes all the multi-instanton corrections to the perturbative 1/N expansion. We show that the nonperturbative partition function, which is manifestly holomorphic, is also modular and background independent: it transforms as the partition function of a twisted fermion on the spectral curve. Therefore, modularity is restored by nonperturbative corrections. We also show that this nonperturbative partition function obeys the Hirota equation and provides a natural nonperturbative completion for topological string theory on local Calabi–Yau 3-folds. 相似文献