管

METHODS: 8 curved artificial root canals were prepared with stainless steel K files by the step-back technique, the root canals were digitally photographed, the images were analysed by the software Image-Pro Plus, the shapes and positions of the root canals were measured and analysed. SPSS10.0 software package was used for statistical analysis, paired-samples t test was used to compare the difference of the means among sample groups.

使用手用不锈钢K锉，按逐步后退法预备8个弯曲人工根管，根管预备过程中对根管及根尖孔进行微距摄影，用图像分析软件Image-Pro Plus对根管的形态与位置变化进行测量、分析；实验数据采用SPSS10.0统计软件包进行统计学分析，选用配对t检验比较组间差异。

Methods 96teeth with pulpitis or periapical periodontitis were instrumented by handling ProTaper rotary instruments using step-down technique,and by K files using step-back technique for control.All teeth were obturated with lateral condensation methods.The efficiency of preparation was analyzed with ra-diographs before and after operation.

选取患有牙髓炎和根尖周炎的后牙96例，随机分成试验组和对照组各48例，试验组用手用ProTaper多锥度镍钛旋转器械逐步伸入法预备根管，对照组用K锉，逐步后退法预备根管，两组均用侧向加压充填法充填根管，根据治疗前后的X线片，评价后牙根管预备效果。

Production of intellectual property rights have an independent national patent products - Bergen plates lined with plastic pipe embedded tendons, Bergen licensing stainless steel double-layer steel-lined metal tube, Bergen tendons embedded double-sided plates lined with plastic pipe, condensation-type lined with plastic pipe, steel mesh skeleton reinforced plastic composite pipe, high pressure bi-metallic tubes, thin-walled stainless steel pipes, galvanized pipes are an alternative to traditional ideals of environmental protection pipe.

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、贝根牌钢衬不锈钢管双层金属管、贝根牌内筋嵌入式双面衬塑钢管、缩合式衬塑钢管、钢丝网骨架增强塑料复合管、高压双金属管、薄壁不锈钢管，是替代传统镀锌管的理想环保管材。

Conductor and ground wire splicing reinforcing bar can reinforce splice sleeves.During line maintenance and emergency repair,it can be used to fix the point of splice sleeve failure conveniently and quickly.

输电线路导、地线接续管补强接续条可以对线路的接续管进行补强，接续管补强接续条在输电线路的维护、抢修时，可方便、快捷地对接续管故障点进行补修。

Based on space-charge effect,I choose different diode model when diodes have different base doping concentration,analyzing the main factors impacting temperature coefficient of the diode,testing diodes with different angle lap,analysis of the blocked characteristics of diode in high temperature.

快恢复二极管的生产中发现大量的反向耐压呈现负温度系数的管芯，本文从空间电荷效应的角度，对基区掺杂浓度不同的管芯采用不同的二极管模型，分析管芯在高温情况下影响二极管反向耐压主要因素；并且对不同磨角的管芯进行测试，分析对二极管高温阻断特性的影响。

Methods: During a three-year period, 84 DPV and 62 OSV were implanted by two neurosurgeons for adult patients with communicating hydrocephalus. Patients medical charts were analyzed retrospectively for demographic data, diagnosis at shunt implantation, valve type, incidence of shunt complications and surgical revision rate.

马偕医院神经外科在三年期间共收录一百四十六例成人交通性水脑症，其中84例使用DPV引流管，62例使用OSV引流管，由病例分析其病人的年纪分布，致病原因，DPV引流管的压力种类，术后并发症及引流管再次手术的机率。

The results show that the porous pipe quantity, head loss and hydraulic deviation rate of the porous pipe would increase while water head in entrance, pipe length and porous pipe permeability increasing. The head loss mainly concentrated on the top half of the porous pipe.

结果表明，随着进水口压力、管长和微孔渗灌管透水性能的增加，微孔渗灌管水流量、沿程的水头损失和水力偏差率增大，且水头损失主要发生在微孔渗灌管靠近进水口的前半段。

B: inner hole standard 54mm, outer diameter 127-160mm or so, various specifications of rolling screws, have modulus rolling rolling round the main motor shaft, fan shaft, worm and other products. C: Three-axis rolling wheels, the standard inner hole 25mm, 25.4mm, 35mm, 40mm, the main hollow tube rolling system, useful connections, art lamp, lighting tube teeth, elbows and so on. D: Automatic lathe accessories: cam, chucks, manual folder, Block, Block, steam-driven folder, sub-degree steam-driven clip seat, horizontal holder, manual horizontal sub-degree holder, a horizontal steam-driven sub-degree Block folder, sub-degree vertical folder manually Block, cylinder folder, CNC lathe tool, diamond grinding wheel, belts, metadata rods, measuring, activities Cam Block, feed rod, dental tube, Grinding, automatic lathes, table lathes, Rolling machine and so on...

产品采用进口钢材合金钢，高速钢专业材料，质量稳定精度高。A：二轴式台湾机型专用3T滚牙轮内孔标准50.5mm，外径90-100mm左右，台湾进口滚制各种规格之螺丝，还有各种直纹，网纹滚丝轮等。B：内孔标准54mm，外径127-160mm左右，滚制各种规格之螺丝，还有模数滚丝轮主要滚制电机轴，风扇轴，蜗杆等产品。C：三轴式滚丝轮，内孔标准25mm，25.4mm，35mm，40mm，主要滚制空心管件，管用接头，美术灯管，灯饰管牙，弯管等等。D：自动车床各种配件：凸轮，夹头，手动夹座，汽动夹座，分度汽动夹座，卧式夹座，手动卧式分度夹座，卧式分度汽动夹座，立式手动分度夹座，筒夹，CNC车刀，钻石砂轮，皮带，元棒，量具，活动凸轮座，送料杆，牙管，磨刀机，自动车床，桌上车床，滚牙机等等。。。

Therefore a GD sand-screening pipe is developed, which is helpful to the environment protection. This new sand-screening pipe consists of center pipe, sand filter and guide shoe. The center pipe is machined from 64mm tubing, and the sand filter is made from silica sand, cement, additive.

这种环保型滤砂管由中心管、滤砂器及引鞋组成，中心管采用 6 4mm油管加工而成，两端为特种 6 4mm平式油管螺纹，管体上每米均匀分布 72个直径 10mm孔眼；滤砂器是根据不同技术标准筛选不同粒度的石英砂、油井水泥、添加剂和水按配比加工压制的。

The process of sand absorption is:(1) the vibration head vibrates and losses the sand layer, and supply high pressure air into the sand absorption head;(2) the high pressure air generates negative pressure in the sand absorption pipe when it is discharged out from the sand absorption;(3) the sand absorption head and the vibration are shifted downwards and maintains the water flow straightly.

取砂土的过程为：(1)振动头振动松散砂土层，同时向吸砂头供入高压空气；(2)高压空气通过吸砂头从排砂管向上排出的过程中，在吸砂管内产生负压，吸砂管将管口处的水和砂土吸入到吸砂头内，在高压气流作用下，吸砂头内的砂、水和气混合而成的三相流通过排砂管排出到受砂船上；(3)在吸砂的过程中，适时地将吸砂头和振动头下移并保持钻孔套管中的水流畅通。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。