“天宫一号”不是梦

我国自行研制的空间站雏形——＂天宫一号＂,已进入生产和实际测试阶段,并将于今年发射升空。这标志着我国的空间实验     

我们都很棒

我伸展双臂,也不能在天空飞翔,会飞的小鸟却不能像我,在地上快快地奔跑。     

东经40°（正负5°）

第一站 俄罗斯 莫斯科 红场上的＂洋葱头＂ 在动身去莫斯科之前,小超有一个建议——向自己的父母学唱这首歌：＂深夜花园里,四处静悄悄,只有风儿在轻轻唱,     

燃烧吧,火烈鸟

火烈鸟（又称红鹤）,是一种大型涉水鸟类,因全身覆盖着美丽的红色羽毛而得名。它是一种古老的鸟类,长着向下弯曲的嘴巴,上嘴平而薄,像眼睑一样覆盖在下嘴上。火烈鸟的脖子有19     

遭遇大脚怪

埃迪轻轻将凯西推到谷仓的角落。 “这样我什么都看不到了。”凯西说。     

Tribology Performance and Adhesive Strength Evaluation of TiAlSiN Coating

Scratch test and friction test were performed to evaluate the internal and external interface behaviors of TiAlSiN coating, respectively. The critical compressive and shearing stress of coating failure during scratch test were calculated and the values are 30.84 MPa and 4.98 MPa respectively. The average friction coefficients of TiAlSiN coating against 2Cr12Ni4Mo3VNbN steel are 0.70 (sliding speed 50 m/min), 0.63 (sliding speed 100 m/min), and 0.81 (sliding speed 150 m/min). The elements diffusion was analyzed by EDS. Al and Si element of coating material diffuse to the steel disc, except Ti element. The oxidation decreases with the increase of sliding speed, but the adhesion increases with the increase of sliding speed. More Al element diffuses to the steel disc at the high sliding speed, but the diffusion of Si element keeps almost constant at different sliding speeds.     

Development of integrated precision vibration-assisted micro-engraving system

A novel precision vibration-assisted micro-engraving system was developed by the integration of fast tool servo and ultrasonic elliptical vibration system, in which the flexure hinge was designed to avoid backlash and PID control algorithm was established to guarantee specific precision. Apart from experimental validation of the performance of the system, various micro-V-grooves cutting experiments on aluminum alloy, ferrous material and hard cutting material were performed, in which Kistler force sensor was used to measure cutting force. Through experiments, it was clear that the vibration-assisted micro-engraving system can ensure good quality of micro-V-grooves and reduce cutting force by about 60% compared with traditional removal process without ultrasonic vibration.     

我把班长变小了

（二十一）孔西西的最新动态 我觉得应该去问问孔西西——即使她不能完全记住喝下去的那口珍珠奶茶的味道,记住一点点儿总是可以的——到时候．我就按照孔西西的记忆来重新调配珍珠奶茶。我相信自己一定能研制出把人变小的配方来。     

馅饼里包了一块天

经典大师秀 琼·艾肯出生在英国,她的爸爸是一位著名的诗人,她的全家都热爱文学,