查询词典 F.

Sporadic E occurs at a lower height than the F layer and this tends to limit the distance over which propagation is possible in a single hop.

分散E 比F 层数和这倾向于限制传播是可能的在一棵唯一蛇麻草的距离发生在更低的高度。

Pattern A and B are for the threads. C is created using the noise filter and vertical motion blur. D is another layer of just noise and E is the scaled version of D. F is a layer with random black and white dots. A and B is passed through a distort-glass filter just to give it that random weaving effect.

图案A和B是细线。C的创建是由杂点滤镜和垂直运动滤镜模糊制作的。D是另一层就是杂点，E是对D的放大结果。F是一层随机的黑白点构成。A和B再通过扭曲里的玻璃滤镜得到一个随机编织效果。

It is concluded, that the E2 layer is a normal layer, controled purely by solar ultraviolet radiation; the annual variation of the solar height at the time of first ionization of the E2 layer is irregular, whereas this solar height of the F layer has a regular annual variation.

可以确认，E2层是一个純受太阳紫外輻射所控制的正常层次；該层每天开始电离时的太阳高度年变化是沒有規律的，而F层每天开始电离时的太阳高度却具有有規律的年变化。

Then the coefficients of entrance region effect and the relations between them, and the flowbehaviour index n can be obtained by solving the energy integral equation. Under the assumption of the velocity distribution within boundary layer: f = 1-(1-η)n+1/n for example, co...

以边界层内幂律流体层流速度分布假设f=(1一η)~(n+1/n为特例，所求出的结果与文献[4]中的理论值和实验值比较表明，本文的计算是既简便又可靠的。

The results showed that the concentration of dissolved organic carbon in leachate from fresh litter fall was lower and that from F layer was higher for both plantations. In Castanopsis plantation, DOC concentration declined with the increasing number of leaching times, whereas that in China fir plantation increased at first then decreased.

光谱特征。结果表明，格氏栲和杉木人工林新近凋落物淋出液的DOC浓度较低，F层淋出液的DOC浓度较高；格氏栲凋落物淋出液的DOC浓度基本上随淋溶次数的增加而降低，杉木的则先升后降。

Lanthanides belong to the sixth cycle of the periodic table Ⅲ B family, are all solid metal, they are La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, holmium, erbium, thulium, ytterbium, and lutetium were 15 kinds of metals and their periphery are two layers of electronic 5d16s2, while the peripheral third layer f orbital but never zero to 14, so the external electronic structure of 4f0-145d16s2, and therefore these elements in oxidation number are to 3, very close chemical properties, extraction, when it is difficult to separate them they are mostly multi-element mineral mix, more difficult to increase refining, and their atomic number of 57-71, one by one to increase the number of protons the nucleus, and thus extranuclear electron of gravity is also growing, so that atomic radius decreases with increasing atomic number Z, which makes lanthanides contraction, ionic radius is also reduced, which also makes Zr, Hf, Nb and Ta, Mo and W, the atom and ionic radius very close to each other they also determine a similar nature, resulting in difficult separation, also the tribe Ⅷ of the fifth cycle, ruthenium, rhodium, palladium, and the sixth cycle, osmium, iridium, platinum is very similar in nature, thus The six elements, said platinum group elements.

镧系元素属于周期表第六周期中ⅢB族，全部是固体金属，它们是镧、铈、镨、钕、钷、钐、铕、钆、铽、镝、钬、铒、铥、镱和镥共十五种金属元素，它们的外围两层的电子均是5d16s2，而外围第三层的f轨道电子却从零增加到14个，所以外围电子结构为4f0－145d16s2，而使这些元素氧化数均为＋3，化学性质极为接近，提炼时很难分开，它们的矿石又大多是多种元素混在一起的，更增加提纯难度，它们的原子序数为57－71，核内质子数逐个增加，因而对核外电子引力也不断增强，使原子半径随原子序数Z增加而减小，这就使镧系元素收缩、离子半径也缩小，这也使得Zr和Hf，Nb和Ta、Mo和W等原子和离子半径都很接近、也决定了它们彼此性质类似，以致难以分离、也使第Ⅷ族中第五周期的钌、铑、钯和第六周期的锇、铱、铂在性质上极为相似，因而称这六个元素为铂系元素。

Furthermore, in the entrance section, again, ratio d/l and ratio h/f are between 10% and 60%.

此外，在入口部分，比例d／|和比例h／f还处于10％和60％之间。

The F ratio is assumed to be unchanged when using multiple antenna elements.

假定 F 比率在使用全向天线元素时是不变的，这种假定基于系统中智能天线的全面部署这一事实。

Thereby F/T-PSA ratio may be useful for the differentiation between BPH and prostate cancer.

因而，F/T-PSA测定可有助于BPH与前列腺癌的鉴别诊断。

In this paper, the relationship between the fatigue crack front straightness S t and fatigue loading ratio f were explored.

通过实验，研究了疲劳裂纹前沿平直度 St与疲劳载荷比 f 之间的关系，发现两者高度正相关，为预制具有平直裂纹前沿的疲劳裂纹提供了有效的途径和方

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。