http://edu-image.nosdn.127.net/EC9D7EA61F1EFFB86E66B5E0259BCBBD.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/13F84D3AF06E795D4BF13D9C8B0AD44F.png?imageView&thumbnail=890x0&quality=100

中国大学MOOC: http://edu-image.nosdn.127.net/8E989C885179CAD3E88F4ED14999CEF9.jpg?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/270D935AC13F8AC30775CB323882970C.jpg?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/E8F4932FC8C534FE91D7CCBE9744E7AD.jpg?imageView&thumbnail=890x0&quality=100

中国大学MOOC: http://edu-image.nosdn.127.net/8E989C885179CAD3E88F4ED14999CEF9.jpg?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/270D935AC13F8AC30775CB323882970C.jpg?imageView&thumbnail=890x0&quality=100

中国大学MOOC: http://edu-image.nosdn.127.net/7D51EA94B193D097167CC61B91F23395.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/46BE8EC842C20D2566C34496757F7637.png?imageView&thumbnail=890x0&quality=100

中国大学MOOC:"下图所示工具为（ ）。http://edu-image.nosdn.127.net/D6BFA044A165F7787DDF229A39C5C236.jpg?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/2F463E8BC7003C7A6DE10AD41DB2F19E.jpg?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/A703FA1F4FAFAE1A1224262AF1D87971.jpg?imageView&thumbnail=890x0&quality=100";

一阶低通和高通滤波电路的特征频率http://edu-image.nosdn.127.net/7E7F1055858242AC1846E34707EA3848.png?imageView&thumbnail=890x0&quality=100与通带截止频率http://edu-image.nosdn.127.net/5EC1781C90A066C15C4A6AFF6EF983C2.png?imageView&thumbnail=890x0&quality=100相等；而高阶低通和滤波电路的http://edu-image.nosdn.127.net/3ED720FB1F05ABA1F9079DE5B7F791B8.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/F711F7FB9E8D3C851ACAABB02F5C6EE7.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/865F0785FF3D04AFFC7A9E21B34598FD.png?imageView&thumbnail=890x0&quality=100。

已知为的DFT，若为实数序列，则为 序列；若为共轭奇对称序列，则为 序列。（）http://edu-image.nosdn.127.net/2B95920BBB41C147CD2111898B530C3C.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/F17B4E48F5DCA4E98032614BCE810896.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/FD30CD9652C9C32517B76378DAC36A9C.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/E698FC70FC599C17EE1E79D4128CE458.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/4B457EA86A75BEB7C241AC5D0BF682E2.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/FD4B8BC6BC00BFFD37FB90DA9B7C8F4B.png?imageView&thumbnail=890x0&quality=100

中国大学MOOC: 夹紧油缸的底板上有（ ）个安装孔。http://edu-image.nosdn.127.net/49DAAC1729B1ECDDEFA08F52714AC010.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/BD127FCFEB45E43ABFDCD0415A146B1D.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/AE1FDBC05A4CEE71744D5ADB4C9685B7.png?imageView&thumbnail=890x0&quality=100

中国大学MOOC: 请结合汉字的属性，依次写出以上图片代表的文字： http://edu-image.nosdn.127.net/BF8B0F1364FBAB8CEFD0A27D00653DE6.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/D2CF59D12FE6D3D50CFA6E56E917D5D8.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/5B8259B62AABCCEE8CB0B5620F3703E5.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/AA429DA8D007E040C06EBA9C89AAF7A8.png?imageView&thumbnail=890x0&quality=100

某化合物相应的IR、http://img2.ph.126.net/kaLkuHYs4M9XAfQNhBGLgA==/1284370318749828257.pngNMR、http://img2.ph.126.net/SsGahxVl1bim2DDLS2Z5vA==/6630758802932226731.pngNMR和MS数据如下所示，推测其结构。（）MS碎片离子质荷比和丰度：http://edu-image.nosdn.127.net/7541672A7D3E93DF185B320AC9AEFFFC.png?imageView&thumbnail=890x0&quality=100http://img2.ph.126.net/kaLkuHYs4M9XAfQNhBGLgA==/1284370318749828257.pngNMR http://img2.ph.126.net/SsGahxVl1bim2DDLS2Z5vA==/6630758802932226731.pngNMRhttp://edu-image.nosdn.127.net/4CF6331CBC47CE21BC11391905498C9C.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/DFDFAD4E63CB717B22C01DE66DD0125A.png?imageView&thumbnail=890x0&quality=100