无环的

The loss of the diesel soot and smoke Cha Cha PAHs in the leaching rate of the most important factor is the length of brewing time;PAHs were detected in the loop on the small number of PAHs,5 of the ring PAHs were only in the low level of test,and the experiment detected no PAHs, detected no 6 of the ring,regardless of diesel smoke or soot Cha Cha,the concentration of PAHs has the highest concentration of dihydrogen Acenaphthene;On the influence of the number of brewing tea,the total concentration and the leaching rate of PAHs in the soot and smoke Chai tea are lower than on the influence of the brewing time and temperature.

其中影响煤烟茶和柴烟茶中PAHs浸出率的最主要因素都是冲泡时间的长短；检测出的PAHs都集中在环数较少的PAH，5环的PAHs仅在较少的试验水平中检出，无6环的PAHs检出，无论煤烟还是柴烟茶中PAHs的浓度都以二氢苊的最高；在冲泡次数影响下，煤烟茶、柴烟茶中PAHs的总浓度和总浸出率，比在冲泡时间和温度影响下要低。

In the second chapter, we consider a kind of Kolmogorov system. The sufficient condition for nonexistence of the closed orbit and existence of the unique and stable limit cycle are obtained by using divergence integral, Poincare-Bendixson theorem and Zhang Zhifenunique theorem.

第二章讨论了一类Kolmogorov系统，利用发散量积分、环域定理和张芷芬唯一性定理，得到了该系统无闭轨的充分条件和存在唯一极限环的条件。

In the second chapter, we consider a kind of Kolmogorov system. The sufficient condition for nonexistence of the closed orbit and existence of the unique and stable limit cycle are obtained by using divergence integral, Poincare-Bendixson theorem and Zhang Zhifen\'unique theorem.

第二章讨论了一类Kolmogorov系统，利用发散量积分、环域定理和张芷芬唯一性定理，得到了该系统无闭轨的充分条件和存在唯一极限环的条件。

Matsuura Bridge, Central Command area of cable-stayed bridge to prestressed cables, cords and duct construction and installation to take GPS global satellite positioning system for spatial orientation, select no wind, no sun in the morning and evening measurements, measured twice a day, any size guarantee 100 meters altitude error of less than 10 mm to ensure the accuracy of the construction.

松浦大桥指挥部对斜拉桥拉索区环向预应力、索导管安装等施工采取GPS全球卫星定位系统进行空间定位，选择无风、无阳光的清晨和傍晚进行测量，每天测量两次，保证百米高空任何尺寸误差在10毫米以内，确保施工精度。

While the diameter of an undirected chordal ring network has been well studied [1], the diameter of a directed chordal ring network and the diameter of a mixed chordal ring network are not known.

虽然「无向的弦环式网路」的直径已被完整地研究、并且可以运用公式得出，但是截至目前为止，「有向的弦环式网路」的直径、以及「混合的弦环式网路」的直径却还未被完全找出来。

In [8, 10, 11], Hwang, Chen, and Wright proposed the directed version of the undirected chordal ring network and derived the diameter of a directed chordal ring network.

在文献[8， 10， 11]中，黄光明老师、陈尚宽学长、以及Wright，将「无向的弦环式网路」推广成「有向的弦环式网路」，并给出计算「有向的弦环式网路」的直径的方法。

The experimental results show that the measurement error might be no more than 1 pixel for perturbance free images.

实验结果表明，对于无扰动的圆环图像其误差小于1个像素；对于有扰动的圆环像误差不超过5个像素。

There were no medieval knights or pirates running around the place now, nor spacemen insisted, there were a few tough looking adolescents who looked much older than their ages.

再无中世纪古堡，再无环跑追逐的海盗，再无走进太空的骄傲（6），只剩下几个其貌不扬的青年，看起来比他们的年龄更苍老。

In present paper a three-dimensional discrete vortex filament method is put forward to simulate the motion and bubble entrainment of an inviscid,incompressible vortex ring .

本文发展了三维离散涡模型用于模拟无粘不可压缩涡环的发展及其与气泡的相互作用，涡环被离散为平均分布在其中心线上的球形涡元，由Biot-Sarvart定律叠加每个涡元的诱导速度得到涡环的运动速度。

In this reaction, DMSO may act as a Lewis base to activate the nucleophile, which facilitates the ring-opening reactions.

与此同时，我们还发现在DMSO中，无催化剂的中型条件下，硫，胺以及各类硅亲核试剂可以对氮杂环丙烷化合物开环。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。