查询词典 X-unit

The structure and stability of all possible isomers of C50X(X=SiH2, PH, S) were investigated by ab initio HF/3-21G calculations. The calculation results indicate that the preferred position for cycloaddition of SiH2, PH, and S on C50 is consistent, i.e. on the C3-C4 and C4-C4 sites of C50, and the resultant most stable cycloaddition isomers are [5,6]-closed and [5,5]-closed structures. The main driving force governing the stability of the C50X(X=SiH2, PH, S) isomers is the strain, or the conjugative effect, or the combination of strain and conjugative effect, depending on the addition positions and the types of the attacked C-C bonds.

用从头算HF/3-21G方法研究了C50的环加成衍生物C50X(X=SiH2， PH， S)所有可能的异构体的结构与稳定性，计算结果表明，SiH2基团、PH基团与S原子在C50上环加成的优先加成位置相同，都为C3-C4类键和C4-C4类键，并且相应形成[5，6]-闭环和[5，5]-闭环结构的最稳定异构体；决定C50X(X=SiH2，PH，S)各异构体稳定性的主要因素，因加成位置以及发生加成反应的C-C键的单双键类型的不同，可能是张力、共轭效应或者二者的共同作用。

Results:Fractures in body,angle and ascending branch of mandible could be showed fine by all these imaging methods. 3D-CT was better than 2D-CT and conventional X-ray plain film in diagnosis of fractures in condyle and coronoid process. Conventional X-ray plain film was poor in diagnosis of the maxillary fractures.2D-CT and 3D-CT were similar in diagnosis of the maxillary fractures.3D-CT showed the jaws fractures directly and stereoscopicly.

结果：对于下颌骨体部、角部和升支骨折，三种影像学都能很好的显示，对于髁状突和喙突骨折，三维CT检查优于常规X线和二维CT；常规X线显示上颌骨骨折较差，而二维CT和三维CT显示的准确性比较接近。

These catalysts were evaluated by a liquid phase hydrogenation of crotonaldehyde to crotyl alcohol and characterized by X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy.

采用沉积－沉淀法制备了纳米Au/TiO2催化剂，以X射线衍射、透射电子显微镜、X射线光电子能谱等手段对催化剂进行了系统的表征，并考察了该催化剂在巴豆醛液相加氢制巴豆醇反应中的催化性能。

In the fifth chapter,the substitution in the B site CuIr_(2-x)M_xS_4 system is investigated.W acts as W~(4+) in the CuIr_(2-x)W_xS_4 system,while Mn exists as Mn~(2+)in the CuIr_(2-x)Mn_xS_4 system.

第五章中我们对B位掺杂体系CuIr_(2-x)M_xS_4进行了研究。W在体系中以W~(4+)存在，而Mn则以Mn~(2+)存在。

Size: 7.9" x 7.9" x 3.1 - Damier canvas, adjustable textile shoulder strap, terracotta textile lining - Matte brown metallic pieces and golden brass zipper - Zipper opening - Outside flat pocket - Carried on the shoulder or across the body PRODUCT ID: N41442 小号 Olav

手袋线条流畅，拉链开合设计，可放记事本、手机、钱包、钥匙等。尺寸： 7.9& x 7.9& x 3.1 - Damier帆布袋身，布肩带可调整长度，赤土色布衬里-褐色哑光金属配件，金色黄铜拉链-拉链开合-手机袋-外贴袋-肩背或斜背参考： N41442

Methods Through questionnaires,the annual number of X-ray diagnostic examination of the whole province was investigated,according to it,hospitals were arranged decreasingly into four levels,and proceeded the stratified random sampling on the rations of

阳性率是判断X射线诊断检查应用是否符合合理应用原则的重要指标之一。X射线诊断检查的阳性率应保持在一个合理的水平上，如果阳性率过低，表明无临床意义的X射线诊断检查的应用过多，应当采取措施予以限制。

The results showed that:(1) the upper elevation limit of the closed forests was found to be 4320 m; the timberline elevations was 4520 m on the sunny side with a gradualtype;(2) for the diameter class structure of the populations, most individuals were from Ⅰto Ⅳ, the number decreased sharply with the increase of diameter class, the survival curves were between Deevey type Ⅰ and Ⅱ, with an approximately stalbe trend; the variation trends of mortality rate q(subscript x and hazard ratek(subscript x were similar;(3)the analysis by time sequence model demonstrated that the individuals of the older age class would be increasing, indicating that S.

死亡率q(下标 x和消失率k(下标 x变化基本趋势一致；都在Ⅲ龄级出现低谷；以后死亡率和消失率曲线均随龄级增加而上升；时间序列分析表明；未来种群发展老龄个体逐渐增多。

X-rays are used because they have the same wavelength as the atomic separations so the crystal acts as a molecular diffraction grating to diffract a beam of X-rays, producing a diffraction pattern that can be captured and analyzed.

之所以使用X射线是因为其波长和原子裂解时的波长一样，所以晶体作为分子衍射光栅衍射X射线，产生一种可以获取并分析的衍射图形。

X-rays are used because they have the same wavelength as the atomic separatio so the crystal acts as a molecular diffraction grating to diffract a beam of X-rays, producing a diffraction pattern that can be captured and analyzed.

之所以使用X射线是因为其波长和原子裂解时的波长一样，所以晶体作为分子衍射光栅衍射X射线，产生一种可以获取并分析的衍射图形。

The crystal monochromator is a key device of the X-ray beamline. It uses crystals as dispersive elements to diffract and separate the synchrotron radiation, and provide X-ray monochmmatic light with a given energy bandwidth.

晶体单色仪是X射线光束线上的关键设备，它用晶体作为色散元件，衍射、分离具有连续光谱的同步辐射，向用户提供一定带宽的X射线单色光。

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。