正螺纹

The transformation relationship from the screw axial section to its orthogonal projection and the compensation are given.

本方法的特点是不需要将丝杆抬起升角角度就可实现测量，给出了在螺纹轴截面和正交投影间基准转换的关系式，并以此讨论分析了补偿量。

Combining with the National Natural Science Foundation ofChina(No.50478032), following researches were done in this thesis: 1 The variation regularity of the ultimate anti-bending capacity of therectangular-sectioned beam with different corrosion has been obtained through thequalitative analysis of 48 beams (32 corroded beams and 12 comparing beams) withaccelerated corrosion; 2 The conclusion has been obtained that the strain of corroded steel bar andconcrete no longer fit in with the assumption of plane section through the analysis ofthe strain data, the strain relation of steel bar and concrete in the mid-span section ofvariously corroded beams at ultimate has been obtained. Through the building of newgeometric relation, the expression of the height of compressive area in the corrodedbeam with rectangular section has been deduced, and the formula with corrosion rateas the main variable for the anti-bending capacity of the corroded concrete beam hasbeen suggested and verified by experiment.; 3 The influence of steel bar corrosion and the concrete regression to the flexureductility coefficient of the corroded structure component has been analyzed. Based onthe relation of steel bar and concrete at yield and ultimate, the expression for theflexure at yield and ultimate of corroded reinforced concrete beam, and the model forthe calculation of the flexure ductility has been built.

本文结合国家自然科学基金项目(50478032)"既有钢筋混凝土桥梁时变可靠度研究"，主要进行了以下研究工作： 1通过对48根快速锈蚀钢筋混凝土矩形截面梁(32根锈蚀梁和12根对比试验梁)数据的定性分析，得到了不同锈蚀率下，锈蚀钢筋混凝土矩形截面梁极限抗弯承载力的变化规律； 2通过对应变数据的分析，论证了锈蚀构件钢筋和混凝土的应变不再符合平截面假定的结论，并通过回归分析得出了不同锈蚀率的螺纹钢筋梁和光圆钢筋梁在极限弯矩作用下，跨中截面处钢筋应变和钢筋处混凝土应变的关系，通过构造新的几何关系，得出了锈蚀钢筋混凝土矩形截面梁计算受压区高度的表达式，既而得出了以锈蚀率为主要变量的锈蚀钢筋混凝土矩形截面梁的正截面抗弯计算建议公式，并通过试验数据加以验证； 3分析了钢筋锈蚀和混凝土劣化对锈蚀构件曲率延性系数的影响，结合钢筋屈服和极限弯矩两种状态下钢筋和混凝土的应变关系，分别得到了锈蚀钢筋混凝土矩形截面梁屈服曲率和极限曲率的计算表达式；既而推导出曲率延性系数的计算模型。

Knife-edged threaded implant with a screw angle of 60°is more appropriate to be used as orthodontic anchorage.

2.60°螺纹顶角的刃状螺纹型种植体比较适合做口腔正畸支抗体。

Shanghai Party Secretary Yu Zhengsheng for wire rod and rebar futures trading opens prompting, Shang Fulin, Chairman of the SFC and Shanghai Mayor Han Zheng inaugurated the joint contract.

上海市委书记俞正声为线材和螺纹钢期货开盘交易鸣锣，证监会主席尚福林和上海市市长韩正共同为合约揭牌。

Professional production, The tool, cutting tool, CNC blade, hole hole groove knife knife, the knife, cut the slot, the circle is collected, hole threads, thread cutter knife blade, cutting and milling knife, acrylic, wheel hub, machine clip blade knife, piston ZhengLiuZi, universal tool, While producing weld dao/machine nipped dao/including difficult and special tools/non-standard tools, and undertake various non-standard customized extension milling styles.

专业生产；外圆车刀，切断车刀，数控刀片，内孔刀，内孔槽刀，外切槽刀，外圆正尖刀，内孔螺纹刀，螺纹刀片，铣刀，铣刀片，亚克力铣刀，轮毂刀，机夹轮毂刀片，雕刻刀，活塞刀，整流子车刀；同时生产焊接刀/机夹刀/包括高难度及特种车刀/非标刀具，并承接非标定制各种款式加长铣刀。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。