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141.
研究了存在内禀退相干时,对于不同的系统初态,具有DM相互作用和各向异性的三粒子XXZ海森伯模型的对纠缠动力学特性.得出了一些结论:系统的对纠缠度与各向异性参数?无关,但内禀退相干对系统的纠缠有明显的抑制作用;在内禀退相干存在时,若系统初态为纠缠态,选择合适的DM相互作用的参数,系统的对纠缠有一个非零的稳定值;系统初态为分离态时,系统的对纠缠会随时间震荡衰减,并且每次震荡会出现纠缠突然死亡现象,系统的对纠缠最终达到解纠缠状态.因此,选择合适的系统初态和DM相互作用参数可以有效地控制系统的对纠缠. 相似文献
142.
143.
Yi Li Xincheng Wang Jing Jing Baorong Xie 《Journal of Dispersion Science and Technology》2013,34(11):1564-1568
Giant vesicles have been of intense interest as the model system for cell membranes. To bring numerous applications of the vesicles into full play, the existence time of the vesicles becomes particularly important. In this work, we explored the existence time of the vesicles in distilled water under four kinds of representative alternative current (AC) electric fields with different energizing time. When the application time of AC electric field reached 1 hour, the existence time of the vesicles reached the maximum value. As the applied electric field time increased, the existence time of the vesicles decreased. Thus, after obtaining the best vesicles on the carbon fiber electrode, disconnecting the external electric field is very necessary. Based on the in situ observation using inverted microscope, the disappearing phenomena of the vesicles were presented. In addition, it is found that vesicles in phosphate buffer solutions (PBSs) can last about 2–3 days when the electric field was applied for 1 hour, which was much longer than that in distilled water. 相似文献
144.
近红外无创生化分析中,要获得准确的血液生化成分信息,需要非常高的系统信噪比。为提高分析系统的信噪比,开展了以增大系统光能利用率为目标的高效双复合抛物面聚光(DCPC)系统研究。首先,针对近红外无创生化分析中光学系统集光要求,研究了复合抛物面聚光器(CPC)出射光特点,确定出一级CPC最大聚光角范围。然后,通过比较标准型和截短型DCPC光能利用率变化,优化出最佳结构参数。最后,结合皮肤组织光学参数,计算了入射光波长为1 000nm时,DCPC系统、CPC-聚焦反射镜系统以及无光学收集系统的光能利用率。结果显示,三种系统的光能利用率分别为1.46%,0.84%,0.26%。设计的DCPC系统增强了对人体漫反射光的收集能力,可有效提高无创生化分析系统的信噪比及整体分析精度。 相似文献
145.
146.
Robert Luxenhofer Stephan Huber Julia Hytry Jing Tong Alexander V. Kabanov Rainer Jordan 《Journal of polymer science. Part A, Polymer chemistry》2013,51(3):732-738
We describe the synthesis and characterization of the first water‐soluble and chiral poly(2,4‐disubstituted‐2‐oxazoline)s. While poly(2,4‐dimethyl‐2‐oxazoline)s are water soluble up to 100 °C, aqueous solutions of poly(2‐ethyl‐4‐methly‐2‐oxazoline) exhibit a lower critical solution temperature. This is discussed in context with its constitutional isomers poly(2‐oxazoline)s and poly(2‐oxazine)s. Circular dichroism spectroscopy revealed strong Cotton effects, which are also responsive to temperature in aqueous solution. It is therefore hypothesized that structures, comparable to polyproline helices, are formed in aqueous solution. In contrast to polyproline, poly(2,4‐disubstituted‐2‐oxazoline)s are highly water soluble and therefore represent very interesting pseudo‐polypeptides that may be useful to develop responsive biomimetic biomaterials. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
147.
Using the classical Mie scattering theory,we compute the energy density of an arbitrary partial wave(e.g.,the nth order) and then determine that the interaction between an incident planar wave and a sphere of radius a is the one between the sphere and those partial waves the order of which satisfies n≤ka.We also provide a simple expression to describe the diffracted wave in which the angle-dependent functions are employed.The difference between the accurate and the approximate expressions is demonstrated by numerical calculation. 相似文献
148.
Nanosized Ni particles with an average diameter of about 8 nm were prepared by reducing of NiCl 2 with sodium borohydride (NaBH 4 ) in aqueous solution. By moderate annealing in protective atmosphere, the composite grew up to be 15-20 nm particles. Both of the as-prepared and annealed Ni particles were coated by a layer of manganese oxide via decomposition reaction in aqueous KMnO4 solution. Hysteresis loops of as-prepared samples show a large increase in the magnetization with decreasing temperature and an unsaturated component at high magnetic field. In contrast, the ferromagnetic characteristics of annealed one are much stronger with large magnetization and coercivity. The thermomagnetic curves verified the coexistence of ferromagnetic Ni and antiferromangetic Mn oxide phases. But there exists no exchange bias behavior in the samples, even though the interface structure between the ferromagnetic Ni core and the antiferromagnetic manganese oxides has been distinctly formed. The absence of exchange bias probably originates from the weak ferromagnetic characteristic of Ni cores. 相似文献
149.
The energy of the stationary axisymmetric Einstein-Maxwell dilation-axion (EMDA) black hole is studied in the context of the Hamiltonian formulation of the teleparallel equivalence of general relativity (TEGR). The energy expression for the finite and arbitrary space-like two spheres is exactly computed by means of the integral form of the constraint equations of the formalism naturally without any restriction on the metric parameters. We also show that our results give the same values obtained by other methods for some special cases. 相似文献
150.
利用二级轻气炮加载技术研究了碳水混合物的冲击压缩特性。研究发现:冲击压力p低于19.0 GPa时,石墨与水混合物冲击压缩特性明显不同于金刚石与水混合物的冲击压缩特性;p大于23 GPa后,它们的特性十分接近;当p为52.9 GPa时,石墨与水混合物表现出反常的冲击压缩特性,压力增加而体积出现膨胀,这与高压下碳与水发生化学反应产生气体相关。还对碳水混合物的相互作用势及混合法则的选取进行了讨论。 相似文献