查询词典 x-rays

In the first part, it was investigated the interaction between Pb2+ and La4Ti9O24 ceramic bulk. The result shows that a significant Pb2+ diffusion into La4Ti9O24 ceramic bulk and a significant crystallization of the La2/3TiO3-type phase is clearly observed in the Pb2+ diffusion layer. The reacted zone consists of the La2/3TiO3-type phase exhibits the linear dependence of the square of the thickness, x, on the heat-treated time, t, in excellent agreement with the parabolic law x2 = kt, where k is the growth rate coefficient. The kinetic study thus indicates that the Pb2+/La4Ti9O24 interaction strictly obeys the theory of the reactive diffusion. Furthermore, the experimental k values were used to determine the associated activation energy, Ea, for the formation of La2/3TiO3-type phase using the Arrhenius plot and the following least-square equation, ln =-Ea/RT + A, where T is the annealing temperature, R is the universal gas constant, and A is a constant, resulting in Ea ~ 607 ?b 60 kJ/mol.

首先， 以巨观的方式观察PbO与La4Ti9O24陶瓷体介面的反应现象；利用X-ray绕射分析以及扫描式电子显微镜来观察不同的热处理温度以及不同的持温时间所制作的样品，研究结果发现， Pb2+离子会渗入到La4Ti9O24陶瓷内，同时在Pb2+离子所渗入的区域内会产生新的La2/3TiO3-type钙钛矿斜方晶相；藉由量测不同温度与时间之样品，其因Pb2+离子渗入而产生之La2/3TiO3-type相层厚度之关系，符合反应式扩散机制中 x2 = kt 之关系式(其中 x：扩散层厚度； k：反应速率常数； t：反应时间)；进一步将不同实验条件所得到之反应速率常数值代入Arrhenius方程式ln (k =-Ea/RT + A ，其中Ea：活化能； T：绝对温度； R：气体反应常数； A：常数，可以求得Pb2+离子与La4Ti9O24陶瓷发生反应式扩散所需之活化能为607 ± 60 kJ/mol。

Vertebral column ; injury ; radiolgraphy ; tomography ; X-ray computed ; magnetic resonance imaging

脊柱；创伤； X线摄影术；断层摄影； X线计算机；磁共振成像

ABSTRACT Amorphization of Cu-Zr system by mechanical alloying of elemental Cu and Zr powder mixtures (30-65at% Cu) and mechanical grinding of the alloys with Cu concentration ranging from 59 to 75at% have been extensively investigated. The structural changes, crystallization behavior as well as atomic short range ordering were followed by differential scanning calorimetry , X-ray diffractometry and nuclear magnetic resonance spectroscopy .

本文采用多种技术系统地研究了球磨Cu和Zr混合粉末制备的Cu〓Zr〓（x=30，33，40，50，55，59，65）非晶合金的形成过程和球磨金属间化合物得到的Cu〓Zr〓（x=59，65，70，75）非晶合金的形成过程，比较了它们形成过程的异同，同时研究了球磨形成的非晶合金的晶化行为以及原子短程有序结构，并与急冷非晶合金作了详细的比较。

Now some of these may be on the X chromosome,.

现在其中一些也许存在于其体内的 X 染色体上。妇女的第二个 X 染色体可以补偿。

Y-direction T(1,0, and at one unit from the x-axis in the element

元的x 轴被输入（T（0，0），和在离开x 轴一个单元长度的y 轴

The second image, as you can see, is located at approximately 0.45 on the x-axis and at

正如你看到的一样，第二张图片位于x轴大约0.45，y周大约0.31的地方，它的尺寸在x和y方向相

Line'.''(measured counterclockwise from the positive half of the x-axis).

x轴和一条直线所形成的角（从x轴的正方向按逆时针方向测量）。

It is an important issue to get the density distributed image inside an object by changing energy spectrum of incident X-ray.

摘 要 通过改变入射的X射线能谱，从而得到物体内部不同密度成分的分布图像的方法，是X辐射成像领域的一个重要课题。

If there is adrop in X-ray receipt when GOES-O is in eclipse behind the Earth,why would there be aspike when the satellite is at dusk?

倘若GOES-O卫星在地球背面被掩蔽时，收到的专业心理测试题目X射线的量消沉了，那卫星在傍晚的时刻X射线的量又若何会上升呢？

If there is adrop in X-ray receipt when GOES-O is in eclipse be你好nd the Earth,why would there be aspike when the satellite is at dusk?

借使倘使GOES-O卫星在地球背面被遮盖时，收到的X射线的量低落了，那卫星在薄暮的时刻X射线的量又奈何会冲天呢？

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。