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991.
The quartz crystal microbalance(QCM) is an important tool that can sense nanogram changes in mass. The hybrid temperature effect on a QCM resonator in aqueous solutions leads to unconvincing detection results. Control of the temperature effect is one of the keys when using the QCM for high precision measurements. Based on the Sauerbrey's and Kanazawa's theories, we proposed a method for enhancing the accuracy of the QCM measurement, which takes into account not only the thermal variations of viscosity and density but also the thermal behavior of the QCM resonator. We presented an improved Sauerbrey equation that can be used to effectively compensate the drift of the QCM resonator. These results will play a significant role when applying the QCM at the room temperature. 相似文献
992.
In this paper, we made a new breakthrough, which proposes a new recursion–transform(RT) method with potential parameters to evaluate the nodal potential in arbitrary resistor networks. For the first time, we found the exact potential formulae of arbitrary m × n cobweb and fan networks by the RT method, and the potential formulae of infinite and semi-infinite networks are derived. As applications, a series of interesting corollaries of potential formulae are given by using the general formula, the equivalent resistance formula is deduced by using the potential formula, and we find a new trigonometric identity by comparing two equivalence results with different forms. 相似文献
993.
High temperature oxidation of metals leads to residual stresses both in the metal and in the growing oxide. In this work, the evolution of this residual stresses is theoretically predicted in the growing oxide layers. The origin of these stresses is based on a microstructural model. Using experimental results providing from the oxidation kinetics, and an analysis proposed to describe the growth strain occurring in the thin layers, a set of equations is established allowing determining the stresses evolution with oxidation time. Then, the model is compared with experimental results obtained on both α-Fe and phosphated α-Fe, oxidised at different temperatures. Numerical data are extracted from experiments either with an asymptotic formulation or with an inverse method. These two methods give good agreement with experiments and allow extracting the model parameters. 相似文献
994.
995.
提出了求解非线性发展方程的新方法——LS解法.LS解法是基于(G’/G)展开法和扩展的双曲正切函数展开法.并引入了Poincar定性理论的思想,然后以Fisher方程为例进行了试验.通过定性分析首先获得了Fisher方程行波系统积分曲线的性质,然后解得了Fisher方程作为耗散系统时单调减少的波前解和作为扩张系统时单调递增的波前解.一些试验结果与Ablowitz所得结果一致.也得到了Fisher方程作为扩张系统时的新结果.LS解法是在定性理论指导下,在已获知解曲线性质的情况下进行精确求解的,求解目标明确.LS解法揭示了线性系统也可以用作辅助方程来求解非线性系统. 相似文献
996.
997.
The extended form of modified Kadomtsev-Petviashvili equation with variable-coefficient is investigated in the framework of Painlevé analysis. The Lax pairs are obtained by analysing two Painlevé branches of this equation. Starting with the Lax pair, the N-times Darboux transformation is constructed and the N-soliton solution formula is given, which contains 2n free parameters and two arbitrary functions. Furthermore, with different combinations of the parameters, several types of soliton solutions are calculated from the first order to the third order. The regularity conditions are discussed in order to avoid the singularity of the solutions. Moreover, we construct the generalized Darboux transformation matrix by considering a special limiting process and find a rational-type solution for this equation. 相似文献
998.
韩伟静 袁伟 朱江瑞 樊琪慧 屈军乐 刘雳宇 on behalf of the U.S.-China Physical Sciences-Oncology Alliance 《中国物理 B》2016,25(1):18709-018709
Metastasis is the leading cause of most cancer deaths, as opposed to dysregulated cell growth of the primary tumor.Molecular mechanisms of metastasis have been studied for decades and the findings have evolved our understanding of the progression of malignancy. However, most of the molecular mechanisms fail to address the causes of cancer and its evolutionary origin, demonstrating an inability to find a solution for complete cure of cancer. After being a neglected area of tumor biology for quite some time, recently several studies have focused on the impact of the tumor microenvironment on cancer growth. The importance of the tumor microenvironment is gradually gaining attention, particularly from the perspective of biophysics. In vitro three-dimensional(3-D) metastatic models are an indispensable platform for investigating the tumor microenvironment, as they mimic the in vivo tumor tissue. In 3-D metastatic in vitro models, static factors such as the mechanical properties, biochemical factors, as well as dynamic factors such as cell–cell, cell–ECM interactions, and fluid shear stress can be studied quantitatively. With increasing focus on basic cancer research and drug development, the in vitro 3-D models offer unique advantages in fundamental and clinical biomedical studies. 相似文献
999.
Through analysing the exact solution of some nonlinear
models, the role of the variable separating method in solving
nonlinear equations is discussed. We find that rich solution
structures of some special fields of these equations come from the
nonzero seed solution. However, these nonzero seed solutions is
likely to result in the divergent phenomena for the other field
component of the same equation. The convergence and the
signification of all field components should be discussed when
someone solves the nonlinear equation using the variable separating
method. 相似文献
1000.
A visualization of Julia sets of the complex Henon map system with two complex variables is introduced in this paper.With this method,the optimal control function method is introduced to this system and the control and synchronization of its Julia sets are achieved.Control and synchronization of generalized Julia sets are also achieved with this optimal control method.The simulations illustrate the efficacy of this method. 相似文献