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Anilinolysis of O‐butyl phenyl phosphonochloridothioate in acetonitrile: Synthesis,characterization, kinetic study,and reaction mechanism 下载免费PDF全文
This paper describes a simple optimized method for the synthesis of O‐butyl phenyl phosphonochloridothioate ( 4 ) under mild conditions. The target compounds were characterized by 1H‐nuclear magnetic resonance (NMR), 13C‐NMR, and 31P‐NMR spectroscopy, as well as mass spectroscopy. The apparent structure of 4 was confirmed by optimization using the B3LYP/6‐311 + G(d,p) level in the Gaussian 09 program in acetonitrile. The nucleophilic substitution reactions of 4 with X‐anilines (XC6H4NH2) and deuterated X‐anilines (XC6H4ND2) were investigated kinetically in acetonitrile at 55.0°C. The free energy relationship with X in the anilines looked biphasic concave upwards with a break region between X = H and X = 3‐MeO, giving large negative ρX and small positive βX values. The deuterium kinetic isotope effects were secondary inverse (kH/kD < 1: 0.789‐0.995) and the magnitudes, (kH/kD), increased when the nucleophiles were changed from weakly basic to strongly basic anilines. A concerted SN2 mechanism is proposed on the basis of the selectivity parameters and the variation trend of the deuterium kinetic isotope effects with X. 相似文献
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本文是关于Mobius不变的Qp函数空间方面的综述文章,给出了近10年来有关Qp函数空间的若干结果、技巧和问题。 相似文献
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由4-氯-6-[2-(吡嗪-2-基亚甲基)肼基]嘧啶(HL)和硝酸银合成了一维链状配位聚合物[Ag(C_(10)H_9N_6Cl)(NO_3)]_n(1)。在配合物1中,中心Ag离子与来自配体吡嗪环上的N5原子及另一配体上的N1、N4、N6原子进行配位,形成了锯齿形的一维链状结构。此外,锯齿形一维链通过N—H…O和N—H…N氢键相互作用及π-π堆积形成了三维的超分子结构。研究结果表明,与配体HL相比配合物1对超氧负离子和羟基自由基具有更强的自由基清除效能;配合物1对不同细菌的抗菌效果也优于配体HL。 相似文献
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硫氰酸铵树脂相分光光度法同时测定天然水中微量铁和钴 总被引:4,自引:0,他引:4
研究了在Tween-80存在的酸性介质中,Fe(Ⅲ)和Co(Ⅱ)与SCN^-形成稳定的有色络阴离子与阴树脂交换吸附,有色络合物富集显色于树脂组上,进行树脂组分光光度集显色于树脂相上,进行树脂相分光光度法同时测定铁和钴的实验条件,Fe(Ⅲ)和Co(Ⅱ)树脂具有色络合物最大吸收波长λmax分别为490nm和630nm,摩尔吸光系数,ε为2.4×10^5L.mol^-1.cm^-1和2.1×10^5L. 相似文献
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Wulan Hasi 《东北数学》1995,(3)
Hardy-LittlewoodTheoremsinMixedNormSpacesonBoundedSymmetricDomainofC~n¥(乌兰哈斯)WulanHasi(DepartmentofMathematics,InnerMongoliaN?.. 相似文献
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本文研究了混合范数空间H(p,q,a)中解析函数f的Taylor系数,对0<p≤2,0<q<∞,a>0和2≤p<∞,0<q<∞,a>0两种情形,分别给出了f属于H(p,q,a)的必要条件和充分条件。用上述结果我们还得到了几个关于混合范数空间的乘子定理,这些结果也推广了Hardy和Littlewood关于H^p空间的相应结论。 相似文献
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W. L. J. Hasi Z. W. Lu S. Gong D. Y. Lin W. M. He R. Q. Fan 《Applied physics. B, Lasers and optics》2008,92(4):599-602
Stimulated Brillouin scattering (SBS) featuring sub-nanosecond response time takes place at a high power threshold, which
enables its application at a high power density. When the intensity of input light excesses the SBS threshold, strong SBS
process takes place through SBS medium, leading to a quick energy transfer from pump to the Stokes and thereby an optical
limiting characteristic in the output energy. In this paper, the correlation between SBS output energy and input power density
is numerically simulated and validated in the Nd: YAG Q-switch laser system. The results indicate that not only the output
energy exhibits an optical limiting characteristic, but also the clamped value of output energy can be controlled by changing
the medium or the focal length. 相似文献
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If f(z) =Σ∞ n=0 anzn and g(z) =Σ∞n=0bnzn for functions f, g are analytic in the unit disc, the Hadamard products of f and g is defined by f * g = ∞ n=0 a n b n z n . In this paper, the Lipschitz spaces Λ(s, α) and QK type spaces are studied in terms of the Hadamard products. 相似文献