周期带

Homogeneous or heterogeneous base material is selected; an alternately superimposed barrier layer and an alternately superimposed recessed layer are grown and formed at the extension of the base material; donor impurity and acceptor impurity are doped in the interface between the barrier layer and the recessed layer and in the interface between the recessed layer and the barrier layer, and the p type group III nitride material doped at a position selecting superlattice is obtained.

选择同质或者异质的基质材料；在基质材料上外延生长形成变换叠加的垒层和阱层，在垒层与阱层的界面和阱层与垒层的界面掺入施主杂质和受主杂质，得选择超晶格位置掺杂的p型III族氮化物材料，其中，每个生长周期的步骤为：生长带隙较宽的垒层，同时掺入受主杂质；生长施主杂质或受主杂质δ掺杂层；生长非掺的带隙较窄的阱层；生长受主杂质或施主杂质δ掺杂层；在N 2 气氛下对所得的选择超晶格位置掺杂的p型III族氮化物材料退火，即得目标产物。

Eight conodont zones and six ammonoid zones are consequently well distinguished in the Lower Triassic of Chaohu, and most of them are regionally or even globally correlative. The δ^13 C, excursion shows two characteristic shifting periods, and this carbon isotope sequence is not only of a stratigraphic value but also of great importance to understanding the biotic recovery and ecosystem reconstruction at the beginning of the Triassic.

巢湖的下三迭统明确包含8个牙形石带和6个菊石带，它们具有区域甚至全球对比意义；巢湖地区早三迭世碳同位素δ^13 C的演变呈现2个显著的漂移周期，这种有特色的碳同位素漂移，不仅具有地层学价值，而且可能对于三迭纪初的生物复苏和生态系演变具有指导意义。

Every fluctuation period of the earlier 4 cycles covered 0.75 to 1 Ma beingsimilar to that of the fourth-order glacial-eustasy with the interval of 0.1 to 1 Ma, imagining there probablyoccurred 4 fourth-order eustasies during the latest Ordovician from the D. complexus Zone to N. ojsuensisZone.

在前4次旋回中，每次波动的周期为0.75～1Ma，与冰川活动引起的Ⅳ级海平面变化周期(0.1～1Ma)相近，以此进一步推断晚奥陶世晚期(从D.complexus带到N.ojsuensis带)发生过4次Ⅳ级海平面变化。

What differ from that of the researchers in the past is the consideration of the direction of Hopf bifurcation with Dirichlet boundary condition , that is, the conditions when the Hopf bifurcation periodic solutions are orbitally asymptotically stable with asymptotic phase.Our basic idea come from the results given by Tang[30]. We adopt the method used by Hassard in the Hopf bifurcation theorem in [24], which is to judge the existence and the direction of Hopf bifurcation, and the stability of the Hopf bifurcation periodic solutions.

与以前的研究者不同的是，本文不仅讨论了在Dirichlet边界条件下系统的Hopf分支在以扩散系数为分支参数的情况下的存在性和分支周期解的空间非齐次性，而且更多的关注了系统在Dirichlet边界条件下Hopf分支解的稳定性及Hopf分支的方向，也即系统定态解在何种条件下，当分支参数如何变化时产生Hopf分支且分支周期解是带渐近位相轨道渐近稳定的。

The second section: Under the conditions of nonlinear boundary controbility, we consider the initial boundary value problem of Camassa—Holm equations with dissipative. By using the contractive mapping fixed point theorem and a priori estimates, the existence of global smooth solution, global attractor in H〓, time periodic solution or almost-periodic solution and the global exponential stability are proved.

第二部分：在非线性控制边界条件之下，对于带耗散项的Camassa—Holm方程的初边值问题，用压缩映射不动点原理及先验估计方法，证明了整体光滑解的存在性、整体解的指数稳定性、H〓空间中整体吸引子的存在性以及时间周期解和殆时间周期解的存在性。

The discovery of annual density bands of mass coral skeleton had a profound effect on coral paleoclimatology, and many patterns of density bands have been revealed throughout the global tropic ocean since then. At the first stage, people tended to explore the control factors of density changes from the environment where the coral grows, but they did not succeed. Since later part of 1980s, some researchers have focused on the skeletal architecture and integrated the signals of both environment condition and skeleton density bands to reveal the mechanism of skeleton density changes, and finally a model of skeleton growth was developed which can explain the almost existed patterns of skeleton density changes.

块状珊瑚骨骼密度条带年周期的发现对后来的珊瑚古气候研究产生了深远的影响，随后又发现世界各热带海域的珊瑚存在多种多样的骨骼密度变化模式，起先常从珊瑚的生长环境中寻找骨骼密度变化的控制因素，但是没有成功，从80年代后期，部分学者试图从珊瑚骨骼构架本身出发、综合考虑环境因素和骨骼密度条带之间的关系来探求骨骼密度变化的机理，并提出了一个可以解释大多数块状珊瑚骨骼密度条带变化模式的骨骼生长模型。

With this system,2D periodic structure with the period of 900 nm is fabricated but defect is introduced.

使用此实验系统制作出了周期为900 nm的二维结构以及周期为数十微米的带缺陷结构。

The correlation detection using the periodicity of the direct sequence autocorrelation function can estimate the symbol period at intermediate frequency or at baseband. Simulation results indicate that the former is superior to the latter when the demodulated frequency is unequal to the carrier frequency.

时域相关检测方法利用扩频信号的周期自相关特性，能在中频和基带对扩频码周期进行估计，仿真结果表明中频检测时性能较好。

The main study areas of SEIZE include:(1)physical nature of asperity;(2)temporal relationships among stress, strain, and pore fluid pressure throughout the earthquake cycle;(3)controls on the updip and downdip limits of the seismogenic zone of subduction thrusts;(4)nature of tsunamigenic earthquake zones;(5)role of large thrust earthquake in mass flux.

SEIZE的主要研究内容包括：①凸凹体的物理性质；②在地震周期里，应力、应变和孔隙流体成分随时间的变化；③在俯冲逆冲断层上，发震带上界和下界的确定；④引起海啸的发震带的特征；⑤大型逆冲带地震在物质转换过程中所起的作用。

With the sinusoidal model of magnetization utilized,a simple expression of demagnetizing energy of an infinitely long ferromagnetic nanostripe is derived.

采用磁化强度分布的正弦模型，推导无限长铁纳米带退磁能的简单表达式，结合数值计算，得到生长在W(110)表面上双原子层铁纳米带初始态磁化强度的周期和纳米带宽度的关系，结果与实验相符。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失