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A series of 2‐(1H‐1,2,4‐triazol‐1‐yl)‐2H‐1,4‐benzothiazines were designed and synthesized by condensation of 1,2,4‐triazole‐substituted ω‐bromoacetophenones and o‐aminothiophenols with the aid of K2CO3 under mild conditions with moderate to high yields. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:332–336, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20434 相似文献
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荧光光谱法研究碳纳米管与牛血清白蛋白间相互作用 总被引:1,自引:0,他引:1
作为一类新型的纳米材料,碳纳米管(CNTs)所具有的独特结构、强细胞穿透能力和低免疫原性等特性引发了生物医学领域的广泛关注,并有望作为一类新型的药物和基因转运载体。因此,研究碳纳米管与生物大分子间的相互作用对其在体内的进一步应用具有极其重要的意义。本文运用荧光猝灭法、同步荧光法以及红边激发荧光位移法(REES法)研究了生理条件下碳纳米管与牛血清白蛋白(BSA)间的相互作用。结果表明,碳纳米管可引起BSA内源性荧光的静态猝灭,但同步荧光和REES的研究结果表明碳纳米管对BSA的构象基本没有影响。同时,通过对碳纳米管与BSA相互作用的机制的探讨,我们推测碳纳米管主要通过非特异性吸附的方式与BSA相互作用。 相似文献
706.
Cyclopalladated ferrocenylimines: efficient catalysts for homocoupling and Sonogashira reaction of terminal alkynes 总被引:2,自引:0,他引:2
A novel pathway for homocoupling of terminal alkynes has been described using cyclopalladated ferrocenylimine 1 or 2/CuI as catalyst in the air. This catalytic system could tolerate several functional groups. The palladacycle 2 in the presence of n-Bu4NBr as an additive could be applied to Sonogashira cross-coupling reaction of aryl iodides, aryl bromides, and some activated aryl chlorides with terminal alkynes under amine- and copper-free conditions, mostly to give moderate to excellent yields. 相似文献
707.
In this article, some conservative compact difference schemes are explored for the strongly coupled nonlinear schrödinger system. After transforming the scheme into matrix form, we prove the existence and uniqueness, convergence and stability of the difference solutions for one nonlinear scheme in the norm by using some techniques of matrix theory. Numerical results show that one nonlinear scheme is the most efficient of all the compact schemes constructed here. It allows much larger time steps than the others. The second most efficient compact scheme is a linear one. We then give numerical simulations to two soliton interactions for the two most efficient compact schemes. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 749–772, 2014 相似文献
708.
The ordinary differential magnetic field line equations are solved numerically; the tokamak magnetic structure is studied on Hefei Tokamak-7 Upgrade (HT-TU) when the equilibrium field with a monotonic q-profile is perturbed by a helical magnetic field. We find that a single mode (m, n) helical perturbation can cause the formation of islands on rational surfaces with q=m/n and q=(m±1,±2,±3,...)/n due to the toroidicity and plasma shape (i.e. elongation and triangularity), while there are many undestroyed magnetic surfaces called Kolmogorov-Arnold-Moser (KAM) barriers on irrational surfaces. The islands on the same rational surface do not have the same size. When the ratio between the perturbing magnetic field Br(r) and the toroidal magnetic field amplitude Bφ0 is large enough, the magnetic island chains on different rational surfaces will overlap and chaotic orbits appear in the overlapping area, and the magnetic field becomes stochastic. It is remarkable that the stochastic layer appears first in the plasma edge region. 相似文献
709.
Single crystalline Li4Mn5O12 nanowires with cubic phase were prepared in a large scale by a simple molten salt route without using any surfactant as template; the nanowires exhibited high storage capacity and coulombic efficiency as cathode materials for lithium-ion batteries. 相似文献
710.