首页 > 导航 > 科普专栏 > 科普PPT

机械零件的失效、选材与工艺分析(0/0)

5秒

您已经浏览完所有图片

时间:2024-12-03 13:35:44 | 浏览次 | 已有条评论

机械零件的失效、选材与工艺分析

没有图集了

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/29d1498d6542439cbd8df22c5697e438.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small29d1498d6542439cbd8df22c5697e438.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small29d1498d6542439cbd8df22c5697e438.png; 1

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/9aca43a3bbb3272c0893bc08a2243055.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small9aca43a3bbb3272c0893bc08a2243055.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small9aca43a3bbb3272c0893bc08a2243055.png; 2

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/7b97b79f6e519f6ea255281f6ece53e5.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small7b97b79f6e519f6ea255281f6ece53e5.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small7b97b79f6e519f6ea255281f6ece53e5.png; 3

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/b98fcc871583ffad2d7079bb6fd37861.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallb98fcc871583ffad2d7079bb6fd37861.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallb98fcc871583ffad2d7079bb6fd37861.png; 4

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/72749eb50773f1c529fefd7bede47f92.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small72749eb50773f1c529fefd7bede47f92.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small72749eb50773f1c529fefd7bede47f92.png; 5

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/1a5970432cb59e6b259925e6456fcf8a.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small1a5970432cb59e6b259925e6456fcf8a.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small1a5970432cb59e6b259925e6456fcf8a.png; 6

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/ee3ccda3c0484f89ed8161910a8b1c51.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallee3ccda3c0484f89ed8161910a8b1c51.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallee3ccda3c0484f89ed8161910a8b1c51.png; 7

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/c6cbdc1d32bfba2ec3d7a5d52c5c37b5.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallc6cbdc1d32bfba2ec3d7a5d52c5c37b5.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallc6cbdc1d32bfba2ec3d7a5d52c5c37b5.png; 8

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/7b42157c6c7790a48dabe6bceec6badb.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small7b42157c6c7790a48dabe6bceec6badb.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small7b42157c6c7790a48dabe6bceec6badb.png; 9

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/2da6a18b32e0266f7cd28f37fb403951.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small2da6a18b32e0266f7cd28f37fb403951.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small2da6a18b32e0266f7cd28f37fb403951.png; 10

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/372402de0d9cb7abaf8cb70a20965516.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small372402de0d9cb7abaf8cb70a20965516.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small372402de0d9cb7abaf8cb70a20965516.png; 11

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/e264f3d0b44858f3ce4cb1325ad9be3c.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smalle264f3d0b44858f3ce4cb1325ad9be3c.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smalle264f3d0b44858f3ce4cb1325ad9be3c.png; 12

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/94598b6991a50115962b654581f85b9d.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small94598b6991a50115962b654581f85b9d.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small94598b6991a50115962b654581f85b9d.png; 13

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/038771c8eeb9fb8500dc15486a4d2e60.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small038771c8eeb9fb8500dc15486a4d2e60.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small038771c8eeb9fb8500dc15486a4d2e60.png; 14

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/915d68d92e3e852f2b9a7c77e339bdcf.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small915d68d92e3e852f2b9a7c77e339bdcf.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small915d68d92e3e852f2b9a7c77e339bdcf.png; 15

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/477916242f7dc3000af6fc1c66ced61f.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small477916242f7dc3000af6fc1c66ced61f.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small477916242f7dc3000af6fc1c66ced61f.png; 16

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/6120b2c03cf6699e03d006723ac5cd7f.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small6120b2c03cf6699e03d006723ac5cd7f.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small6120b2c03cf6699e03d006723ac5cd7f.png; 17

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/fda3b776a4001b8454d3d605bd4b7c76.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallfda3b776a4001b8454d3d605bd4b7c76.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallfda3b776a4001b8454d3d605bd4b7c76.png; 18

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/9153ad2686aa6e84e179238537080373.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small9153ad2686aa6e84e179238537080373.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small9153ad2686aa6e84e179238537080373.png; 19

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/561050c7afd44f4e83876ae52ad97717.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small561050c7afd44f4e83876ae52ad97717.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small561050c7afd44f4e83876ae52ad97717.png; 20

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/8e57d683d7113e0be0430246217b0bea.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small8e57d683d7113e0be0430246217b0bea.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small8e57d683d7113e0be0430246217b0bea.png; 21

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/f783104667b9b7c2c26bc8d09e5ab219.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallf783104667b9b7c2c26bc8d09e5ab219.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallf783104667b9b7c2c26bc8d09e5ab219.png; 22

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/1d31f5fb7a23423e5f2a16b7eca5bd61.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small1d31f5fb7a23423e5f2a16b7eca5bd61.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small1d31f5fb7a23423e5f2a16b7eca5bd61.png; 23

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/da434c1e05f5ec3c8d50bc477854e885.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallda434c1e05f5ec3c8d50bc477854e885.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallda434c1e05f5ec3c8d50bc477854e885.png; 24

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/3826ed7fc1ab32fbb562396f2e837b54.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small3826ed7fc1ab32fbb562396f2e837b54.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small3826ed7fc1ab32fbb562396f2e837b54.png; 25

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/b82bbb2bd4a48b8750eb067746dcb205.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallb82bbb2bd4a48b8750eb067746dcb205.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallb82bbb2bd4a48b8750eb067746dcb205.png; 26

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/3c6c7403002fa33831bfef5e3ce2cf34.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small3c6c7403002fa33831bfef5e3ce2cf34.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small3c6c7403002fa33831bfef5e3ce2cf34.png; 27

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/6bdceaf225bab03bce8d6d0e6cc8528b.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small6bdceaf225bab03bce8d6d0e6cc8528b.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small6bdceaf225bab03bce8d6d0e6cc8528b.png; 28

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/86e051b9ce9a9fc15ae72bffa003364a.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small86e051b9ce9a9fc15ae72bffa003364a.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small86e051b9ce9a9fc15ae72bffa003364a.png; 29

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/34817ef5fb9878ebebd61eaacd274074.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small34817ef5fb9878ebebd61eaacd274074.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small34817ef5fb9878ebebd61eaacd274074.png; 30

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/88bbe5028be35c816b6d181e7ec8067d.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small88bbe5028be35c816b6d181e7ec8067d.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small88bbe5028be35c816b6d181e7ec8067d.png; 31

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/c618802bcfc3ef1abb6da7522e7d6058.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallc618802bcfc3ef1abb6da7522e7d6058.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallc618802bcfc3ef1abb6da7522e7d6058.png; 32

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/b0af62f7859f9b8b2438a496b5e664dc.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallb0af62f7859f9b8b2438a496b5e664dc.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smallb0af62f7859f9b8b2438a496b5e664dc.png; 33

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/4692265bf5bd24d68e710ba601f0963c.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small4692265bf5bd24d68e710ba601f0963c.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small4692265bf5bd24d68e710ba601f0963c.png; 34

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/5b22a2e05b22b0217e60364b782de3c1.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small5b22a2e05b22b0217e60364b782de3c1.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small5b22a2e05b22b0217e60364b782de3c1.png; 35

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/81ce3a4df511b9c0a4ecf6e39367dbaa.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small81ce3a4df511b9c0a4ecf6e39367dbaa.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small81ce3a4df511b9c0a4ecf6e39367dbaa.png; 36

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/6463b68f1dfc8d2f9d461689a28eaf4c.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small6463b68f1dfc8d2f9d461689a28eaf4c.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small6463b68f1dfc8d2f9d461689a28eaf4c.png; 37

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/54de9c51d46f91128524f0a924c4966d.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small54de9c51d46f91128524f0a924c4966d.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small54de9c51d46f91128524f0a924c4966d.png; 38

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/277c7c773a7c2e8d1affef8c8758f7a5.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small277c7c773a7c2e8d1affef8c8758f7a5.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small277c7c773a7c2e8d1affef8c8758f7a5.png; 39

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/5cabc1ca71e9a800cd8bd801d73fcc24.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small5cabc1ca71e9a800cd8bd801d73fcc24.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small5cabc1ca71e9a800cd8bd801d73fcc24.png; 40

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/e2bd2ab9b9c65250db150abf6ecbb595.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smalle2bd2ab9b9c65250db150abf6ecbb595.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smalle2bd2ab9b9c65250db150abf6ecbb595.png; 41

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/dd93dc6540a73334854bc36a1cc4030d.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smalldd93dc6540a73334854bc36a1cc4030d.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/smalldd93dc6540a73334854bc36a1cc4030d.png; 42

: http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/3f371884613f37f4e4194de4450d648c.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small3f371884613f37f4e4194de4450d648c.png; http://www.ecorr.org.cn/d/file/dhTJDAOHANG/kepuzhuanlan/kepuppt/2024-12-03/small3f371884613f37f4e4194de4450d648c.png; 43

科普PPT