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Secondly, some influences of fringing field are taken into account , an effective dielectric constant is introduced ,and the resonant frequency expression is modified as well.

在某些情况下，谐振频率需要被调谐，为此，在基片和地板之间引入一层空气隙，可以改变微带天线的某些性能，特别是谐振频率。

The certification defines creepage distance as the shortest surface path over a solid dielectric between two galvanically isolated conductors.

这个证明规定了漏电距离为沿最短表面路径穿过固态电解质，两绝缘导体之间的距离。

Objective To study changes of dielectric properties of gastrocnemius caused by simulated weightlessness.

目的 在40 Hz～110 MHz频率范围观察模拟失重10 wk大鼠离体腓肠肌细胞介电特性的改变。

Objective To study changes of dielectric properties of gastrocnemius caused by simulated weightlessness.

目的在40Hz～110MHz频率范围观察模拟失重10wk大鼠离体腓肠肌细胞介电特性的改变。

Changes of dielectric property of gastrocnemius induced by simulated weightlessness can be observed effectively by frequency domain impedance technique.

利用频域阻抗技术可以有效地观察到模拟失重导致的腓肠肌细胞介电特性发生的改变。

Good thermal stability and self-extinguishing behavior was observed with the cured polybenzoxazine resins. Second, furan-containing benzoxazine monomers, P-FBz, BPA-FBz, and 4FP-FBz were prepared using furfurylamine as a raw material. Formation of furfurylamine Mannich bridge networks in the polymerizations of P-FBz and BPA-FBz increased the cross-linking densities and thermal stability of the resulting polybenzoxazines. P-FBz and BPA-FBz- based polymers also exhibited high glass transition temperatures above 300℃, high char yields, and low flammability with a limited oxygen index value of 31. The dielectric (Dk3.21–3.39) and mechanical properties (high storage modulus of 3.0–3.9 GPa and low coefficient of thermal expansion of 37.7– 45.4 ppm) of the P-FBz and BPA-FBz-based polymers were superior or comparable to other polybenzoxazines. 4FP-FBz used for polybenzo- xazine modification by means of formation of benzoxazine hybridation with P-FBz.

第二部份以2-呋喃甲胺为起始物，制备了P-FBz、4FP-FBz与BPA-FBz 三个含呋喃官能基之氧代氮代苯并环己烷的单体；BPA-FBz与P-FBz於开环聚合中形成之Mannich bridge网状结构有效地提升聚氧代氮代苯并环己烷聚合物之交联密度与热安定性；Poly与Poly具有大於300℃之玻璃转移温度、高的焦炭生成率与具有31之极限氧指数(Limited oxygen index， LOI)的难燃性特质，Poly与Poly之介电常数(Dk=3.21~3.39)与机械性质[3.0~3.9 GPa的储存模数与37.7~45.4ppm之低热膨胀系数( Low coefficient of thermal expansion， Low CTE)]均较其他聚氧代氮代苯并环己烷为优；4FP-FBz具有低之介电常数(Dk=2.7)，以其作为降低介电常数之反应型改质剂，与P-FBz混成，证实可有效地降低Poly的介电常数。

First, we deduce theoretical formulae of calculating equivalent dielectric constant and resonance frequency of rectangular microstrip antennas with air gaps from electromagnetic field theory based on the modified theory of cavity model. Then, we discusses the radiant principle of microstrip antennas on the base of transmission line theory and analyzes the problem of air gaps how to influence pattern and other idiocratic parameters of a microstrip antenna in detail.

本论文的主要工作是根据修改的微带天线的腔模理论，利用电磁场理论推导了具有空气隙的矩形微带天线的等效介电常数和谐振频率的理论计算公式，同时以传输线理论为基础，论述了微带天线的辐射原理。

Based on the theory of radio-freqency impendence, the dielectric constant of water is much greater than that of oil, so they show different properties in the respect of radio impedance.

水的介电常数远大于油的介电常数，因而两者呈现不同的射频阻抗是油品含水量测量的理论依据。

It is found thatthe fractal dimension D=1.25 corresponds to the lowest criticalcoupling constant αc=1.9,D=1.73 corresponds to the highest criticalratio of dielectric constants ηc=0.163,and when D≤1.145 bipolaronscan not exist at any rate.In chap,4,we will propose a novelapproach to the calculation of the exciton ground-state energy for thestrong-coupling case.Different from all previous methods,the wavefunction of the phonon part is assumed to take a form related to thewave function of the relative motion.We obtain the exciton energy bysolving the derived integrodifferential equation rather than select ahydrogen-like form to minimize the energy expectation.

结果发现，分数维的维数D＝1.25对应最小的临界的电-声耦合常数(αo＝1.9)，D＝1.73对应最大的临界的介电常数比(ηc＝0.163)，当分数维的维数D≤1.145时，双极化子无论如何也不可能存在，在第四章中，我们将提出一种新颖的变分方法来计算强耦合的激子-声子系统的基态能，不同于以前所有的方法，我们取声子的波函数与相对运动波函数有关的形式，而不是假定一个固定的关于相对运动坐标r的函数形式，得到相对运动波函数所满足的非线性的微分积分方程，我们数值求解这个微分积分方程得到系统基态能，而不是选择一个类氢原子的波函数变分使得能量的期待值最小。

The AlGaInP LED layers with dielectric-metal reflector is invertedly bonded to the GaAs submount by using 80Au-20Sn alloy as a solder (Reflector-Submount, RS-LED), and then GaAs substrate is removed.

通过与常规AlGaInP吸收衬底LEDs和带有DBR的AlGaInP吸收衬底LEDsAS-LED(DBR电、光特性的比较，证明新型全方位反射AlGaInP薄膜LED结构能极大提高亮度和效率。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。