查询词典 F.

These antennas can cover GSM900/DCS/PCS/UMTS operation. In the chapter 2, the antenna is designed based on the concept of monopole antenna. Furthermore, the antenna structure have two radiant paths and coupled each other at tail end to do impedance matching. In addition, to raise distance between radiation plane and ground will avoid capacitative effect effectually. In the chapter 3, the antenna is designed based on the concept of planar inverted-F antenna. Furthermore, that the antenna structure have two radiant paths and coupled each other at tail end to do impedance matching is similar to chapter 2. But there is a difference in them. We can choose the short position to change input impedance at this structure. In the chapter 4, the antenna is designed based on the concept of planar inverted-F antenna which takes coupled-fed. It will produce the first mode and high-order mode near the frequency, 900MHz. The feature of this type is to reduce the volume effectually. This antenna can not only cover GSM900/DCS/PCS/UMTS operation but maintain good radiation efficiency. Finally, we will compare three antennas, and develop procedure with industrial view, and propose the prospect of the GSM/GPRS antenna in PND, as a conclusion.

在第二章中，我们使用单极天线设计概念，使用双路径架构并於末端耦合来对天线阻抗做匹配，产生涵盖GSM900/DCS/PCS/UMTS四频操作频带，并提高与接地面的辐射高度，以避免电容效应，使天线具有良好的辐射特性；在第三章中，使用倒F形天线设计概念，使用双路径架构於末端耦合，并於辐射臂上采取适当接地点电感效应作输入阻抗匹配，达成涵盖GSM900/DCS/PCS/UMTS系统的四个操作频带；在第四章中，采用倒F形架构并使用耦合馈入方式，使得长辐射金属臂在低频900 MHz附近产生共振，产生低频基频模态及高阶模态，以达成宽频及频宽涵盖GSM900/DCS/PCS/UMTS频带操作，并有效缩减使用体积；最后，分别比较此三种架构的优缺点，再加以业界角度来思考，研发产品天线的流程及思考方向，以及天线应用於可携式导航装置中未来的展望作为本论文的总结。

The capital parameters of the optical system are f���=1 600mm,2ω=18°×0.148°, F/number=F/10,and all surfaces are conicoid.

光学系统的基本参数为：焦距f′=1 600 mm，视场角为2 w=18°×0.148°，相对孔径为1／10，3个反射面均为二次曲面。

Non-fluoride ionic number of Nd-F in dilute LiF-NdF3 melts and Nd-O-F species in dilute LiF-NdF3-Li2CO3 melts was researched by cryoscopic method,respectively.

采用冰点降低法分别研究了以LiF为溶剂的稀LiF-NdF3熔盐中Nd-F离子团及LiF-NdF3-Li2CO3熔盐中Nd-O-F离子团的非氟离子的个数。

The cardiomyocyte viability were detected by MTT assay for calculating the survival rate and the inhibitory rate of the virus. Myocardial F-actin and VEGF were analyzed by immunofluorescent staining with confocal microscopy. Mean fluorescent intensity of F-actin and VEGF were determined by flow cytometry.Results There is no toxicity on cardiomyocytes when PD is at concentration of 0.02 mmol/L and 0.2 mmol/L while there is toxicity at concentration of 2 mmol/L. CVB3 could reduce the viability of cardiomyocytes, depolymerize F-actin cytoskeleton and reorganize VEGF protein.

体外培养心肌细胞，用100 TCID50柯萨奇B3病毒（CVB3）感染心肌细胞，建立病毒性心肌炎实验模型，然后分别用0.02mmol/L、0.2mmol/L、2mmol/L三种不同浓度的PD处理感染CVB3病毒的心肌细胞，观察心肌细胞的形态和搏动，用细胞免疫荧光技术标记纤维状肌动蛋白和VEGF蛋白，四唑蓝比色法测定心肌细胞活性和病毒抑制率，流式细胞仪检测各组心肌细胞VEGF蛋白和F-actin平均荧光强度。

In the BC〓F��� and BC〓F��� generation of Yannong15×Thinopyron intermedium hybrid, 4 octoploids which had chromosome number of 2n=56 and could form 28 bivalent at PMC MI, 14 disomic addition lines which had chromosome number of 2n=44 and could form 22 bivalent at PMC MI; three monosomic addition lines which had chromosome number 2n=43 and had the chromosome configuration of 21Ⅱ+1Ⅰ at PMC MI, 1 substitution line which had chromosome number 2n=42 and could form 21 bivalent at PMC MI were selected by observation of mitosis in root tip cell and meiosis in pollen mother cell.

在烟农15与中间偃麦草杂交的BC〓F〓和BC〓F〓代中，通过根尖有丝分裂和花粉母细胞减数分裂中期Ⅰ观察选出4个2n=56，PMC MI染色体构型为28Ⅱ的八倍体小偃麦；14个2n=44，PMC MI染色体构型为22Ⅱ的双体异附加系；3个2n=43，PMC MI染色体构型为21Ⅱ+1Ⅰ的单体异附加系；1个2n=42，PMC MI染色体构型为21Ⅱ的异代换系。

Based on an analysis of distribution pattern of hydrocyclone"s axial velocity, by changing the inlet flow rate Qi and split ratio Fand making an investigation in the effect of Qi and F on axial velocity field, the factors causing the forming of short-cut circuit and circulating flow are found. It is considered that the short-cut circuit and circulating flow are produced by the structure of the hydrocyclone, and can"t be eliminated completely, though they interfere the flow field inside a hydrocyclone and affect the separation accuracy. Test results show that, by increasing Qi and F and controlling them in a certain range, the separation efficiency of the hydrocyclone can be improved.

在研究旋流器轴向速度分布规律的基础上，分析了短路流与循环流的形成原因，试验研究了改变操作参数，即改变入口流量Qi与分流比F对轴向速度场的影响认为短路流与循环流是由旋流器结构决定的，很难完全消除，它们干扰了旋流腔和大锥段的流场，在一定程度上也影响了分离精度试验结果表明，加大入口流量Qi与分流比F，并将其控制在一定范围内，便可提高分离效率这项研究对水力旋流器分离机理的认识与实际应用均有重要意义

To reduce the marking distortion , using the vertical 2 - dimension galvanometer distributing and f field lens focalize , the distance of the second galvanometer to the machining plane is the focus f . to avoid too hign temperature to distroy the resonance cavity because of too long marking time , cooling system and self - protector is used in the design

为减少打标畸变，采用垂直二维振镜分布， f物镜聚焦，将激光束经第二个振镜反射后到加工平面的距离为焦距f ，为了避免打标时间过长，温度过高破坏谐振腔，在设计中加上冷却系统和自我保护装置。

Starting with commercial available tosylmethyl isocyanide and but-2-enoic methyl ester, pyrrolo[2,1-f][1,2,4]triazine derivatives was prepared by twelve-steps process in total yiled of 5.0%~8% via pyrrole and pyrrolo [2,1-f] [1,2,4] triazine ring formation, substitution and amination reactions etc.

本文以简单的对甲基苯磺酰甲基乙腈和反-2-丁烯酸为原料，经过形成吡咯，吡咯并[2，1-f][1，2，4] 三嗪环，取代，酰胺化等等12步反应，合成了结构新颖的吡咯并[2，1-f][1，2，4] 三嗪衍生物，总收率达5%～8%。

The heaviest solid (iridium, density r s = 22.6g/cm3, size f 4mm) and liquid (mercury, density r s = 13.6g/cm3, size f 5×2mm ) on the earth is acoustically levitated by greatly enhancing both the levitation force and stability through optimizing the geometric parameters of the self-developed single-axis acoustic levitator.

以上述理论为指导，对自行研制的单轴式声悬浮装置进行了优化设计，显著提高了悬浮力和悬浮稳定性，悬浮起自然界中密度最大的固体铱（ Ir ，密度 r s =22.6g/cm3，尺寸 f 4mm ）和液体汞（ Hg ，密度 r s =13.6g/cm3、尺寸 f 5×2mm ）。

The strains are arranged in order in terms of biological characteristics as follows: B_ 、B_5、 F-263、 B_1、 B_6、 B_f��� B_(y2)、 B_(12)、B_z、 B_9、 B_3、 B_(14)、 B_2、 B_4、 B_8、 B_(13)、 B_(y7)、 B_(11)、 B_(10)、 B_7、 B_(15); through comparing the mortality and muscardine rate to Monochamus alternatus larva of 21 strains, it is found that B_5、B_ and F-263 are superior to other strains.

比较生物学性状，结果从优到劣排序是：B_、B_5、F-263、B_1、B_6、B_f、B_(y2)、B_(12)、B_z、B_9、B_3、B_(14)、B_2、B_4、B_8、B_(13)、B_(y7)、B_(11)、B_(10)、B_7、B_(15)；比较各菌株对天牛幼虫的致死率和白僵率，B_5、B_和F-263三个菌株优于其它菌株。

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。