管

Methods Sixty human teeth with single root were instrumented using step-back technique, then were divided into six groups and treated with different concentrations EDTA paste and NaClO solution.

选择60颗离体单根管牙，用逐步后退法预备根管，预备后随机分成6组，采用不同质量分数的EDTA糊剂对根管进行处理，分别为5%、10%、15%、17%和20%EDTA糊剂，另设生理盐水组作为对照。

Group 1 was instrumented with SS-K files by step-back technique, group 2 was instrumented with manual Protaper instruments according to manufacturers' directions.

第一组使用不锈钢K锉采用逐步后退法预备近颊根管，第二组使用手用Protaper采用厂家推荐的方法预备近颊根管，第三组使用机用K3采用逐步深入法预备近颊根管。

Methods: One hundred and twenty teeth with curved root canals were randomly divided into 2 groups: 74 curved root canals in group PT were prepared by ProTaper rotary Nickel-Titanium file with crown-down technique, and 75 curved root canals in group SS were prepared by K-files with step-back technique.

选择2005年6月至12月间本院口腔内科行根管治疗的120例患者（120颗牙），随机分为两组：试验组用ProTaper机用镍钛锉及冠根向预备技术预备弯曲根管74个，对照组用不锈钢K型锉及逐步后退法技术预备弯曲根管75个。

This article analyzes some regulations for safety steering column,discusses the distribution of crashing and the structures and the safety control principls with flex steering shaft,breaking steering shaft,sleeve steering pillar tube as well as ripples tube steering pillar tube.

分析了安全转向柱的法规要求，汽车碰撞能量的分配，伸缩式转向轴、可断开式转向轴、套筒式转向柱管、波纹管式转向柱管等的结构和安全控制原理。

PTFE referred to F4, because of its excellent dielectric properties and corrosion-resistant chemical (high temperature of the molten fluoride elements and the state of alkali metal), non-absorbent, non-stick, not conductive, low coefficient of friction and not Ageing properties, and is widely used in chemical, petroleum, textile pharmaceutical, metallurgy, machinery, electronics, electrical appliances, electricity, food and aviation, military and scientific research in all walks of life, I plant the development of metal bellows, compensation , PTFE bellows F4 tetrafluoroethane compensator, F4 metal composite compensation, anti-corrosion steel liner tetrafluoroethane pipe, steel-lined tetrafluoroethane three links, elbow, Stone, the reaction tower, tower chloride, lining tetrafluoroethane valve Doors, tetrafluoroethane pads and steel-lined polypropylene pipes and accessories, and earnestly solve the user in the production process by the various anti-corrosion problems.

聚四氟乙烯简称F4，由于其优异的介电性能与耐化学腐蚀性(高温下的氟元素和熔融状态下的碱金属外)，不吸水、不粘、不导电、摩擦系数低及不老化等性能，而被广泛应用于化工、石油、轻纺制药、冶金、机械、电子、电器、电力、食品及航空、军用与科研等各行各业中，我厂开发的金属波纹管、补偿器，四氟波纹管F4四氟补偿器、F4金属复合补偿器，钢衬四氟防腐管件，钢衬四氟三通、弯头、四通、反应塔、氯化塔、衬四氟阀门，四氟垫片以及钢衬聚丙稀管道及配件，切实解决了用户在生产过程中所遇到的各种防腐问题。

The country produced its own independent intellectual property rights of patent products -- Bergen plates embedded Lining Plastic Pipe tendon. Bergen licensing double stainless steel-lined metal, reinforcement plates embedded Bergen double Lining Plastic Pipe, Bergen-licensing Lining Plastic Pipe condensation. Bergen licensing steel skeleton reinforced composite plastic screen to five types of products.

公司生产拥有独立知识产权的国家专利产品——贝根牌内筋嵌入式衬塑钢管、贝根牌钢衬不锈钢双层金属管、贝根牌内筋嵌入式双面衬塑钢管、贝根牌缩合式衬塑钢管、贝根牌钢丝网骨架增强复合塑料管等五大类产品。

Through the test,it is indicated that not only the strength of square bird-beak SHS joint is higher than the corresponding square conventional tube,but also have a higher strength than pipe joint with a similar cross-section.

钢管相贯节点是钢管结构的主要结点形式之一，试验研究发现：方管&鸟嘴&型相贯节点不仅比相对应的常规方管节点强度高，而且普遍比具有相近横截面的圆管节点强度高。

The resulting vertical and horizontal slant angular displacement of bullet in half constraint region was presented during gun-firing, and the influence of rotor rotational speed and barrels clamp cone angle on initial ballistic dispersion were also discussed.

结果表明，半约束期内旋转离心力和身管组半锥夹角导致的科氏力对弹丸起始扰动有影响，同时弹丸偏角将随着身管转速的增加而线性增加，特别是高射速时，弹丸的偏角更大，这些可为转管武器的射击精度研究提供参考。

Apart from the working limitations resulting from its structural property, the flat plate heat pipe carries out heat dissipation through the evaporation and condensation of the working fluid. Thus, if the working angle of the fluid is adverse to its backflow, the heat pipe will fail easily. Furthermore, not the orientations of all the heat sources are favorable to the functioning of the heat pipe. To compensate for this drawback, this research focuses primarily on the development of a composite structure which will reduce the effect of gravity on the working fluid. Generally speaking, the heat pipe is divided into three main categories: the groove type, sintered metal type and mesh screen type, as shown in Table 2. As far as capillary force is concerned, the sintered metal type and mesh screen type show better performance. As mentioned in R.

平板式热管除了因其结构特性而产生的工作极限之外，由于其作用乃是透过工作流体的蒸发及凝结进行散热，故若是其工作角度不利于液体之回流，便容易使热管失效，且并非所有之发热源都是位于有利于热管工作之位置，因此本研究之主要目的为设计一可减少重力对工作流体影响之复合式结构；一般而言，热管之结构大致可分为沟槽、烧结及网格三种(如表2所示)，其中烧结及网格结构有较佳之毛细力，在 R。

The results show that:(1) The space-charge fields(include dc space-charge fields and ac space-charge fields) have important effect on the beam-wave interaction output power, make the saturated output power lower, saturated position delay;(2) The back-radio excited by the electron beam has little effect on the output power, and can be ignored;(3) The transverse motions of electron beam has some effect of the output power;(4) The means of phase velocity taped and bunch compression can improve the relativistic TWT efficiency, especially bunch compression can greatly improve the efficiency.

五、分析了相对论行波管三维非线性特性，分析结果表明：(1)空间电荷场（包含直流和交流空间电荷场）对注波互作用输出功率影响很大，会造成饱和输出功率减小，饱和位置推后；(2)电子注激发的反向辐射对输出功率影响比较小，基本上可以忽略不计；(3)电子注横向运行对注波互作用的直接影响比较大；(4)通过改变耦合腔内半径来调节慢波结构相速，采用相速跳变和预群聚的方法可以改善相对论行波管的效率，特别是采用预群聚方法，可以尽量提高相对论行波管的效率。

Chrysanthemum of 10 thousand birthday is lax to edaphic requirement, with the arenaceous qualitative loam with fecund, good drainage had better.

万寿菊对土壤要求不严，以肥沃。排水良好的砂质壤土为好。

He unstepped the mast and furled the sail and tied it.

他拔下桅杆，把帆卷起，系住。