| ²é¿´: 1365 | »Ø¸´: 5 | ||
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·³ÉÓ¢ÓïµÄ£¬¾¡Á¿µØµÀһЩ°É£ºÏÖÔÚ¼¸°ÙÍò¹«ÇêµÄÍÁµØÊ¹ÓÃËÜÁÏĤ£¨plastic mulch£©£¬µ¥µ¥ÔÚÖйú£¬1989Äê¾ÍʹÓÃÁ˶þ°Ù°ËÊ®ÁùÍòÆßǧ¶à¹«ÇêµÄµØÄ¤£¬ÕâÒ»Ôö³¤ÊǺÜÏÔÖøµÄ£¬1979Äê²ÅʹÓÃ40¶à¹«Çê¡£ ·³ÉÖÐÎĵģ¬ÎÒÀ´Äò»×¼Òâ˼£º There are as many partial derivatives£¨Æ«µ¼Êý£©of the first order£¨Ò»½×£©as there are independent variables£¨×Ô±äÁ¿£©. |
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alvarohao
Ìú¸Ëľ³æ (ÖøÃûдÊÖ)
- ·ÒëEPI: 85
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ¹ó±ö: 0.005
- ½ð±Ò: 13664.2
- ºì»¨: 3
- ɳ·¢: 5
- Ìû×Ó: 2355
- ÔÚÏß: 261.5Сʱ
- ³æºÅ: 1402388
- ×¢²á: 2011-09-15
- ÐÔ±ð: MM
- רҵ: »úе½á¹¹Ç¿¶Èѧ
¡¾´ð°¸¡¿Ó¦Öú»ØÌû
¡ï
°®ÓëÓêÏÂ(½ð±Ò+1): 2011-10-29 16:11:59
lljy(½ð±Ò+4): 2011-10-30 22:30:09
wg423(·ÒëEPI+1): Â¥Ö÷·¢·Å´íÎ󣬴ú·¢ 2011-10-31 20:19:45
°®ÓëÓêÏÂ(½ð±Ò+1): 2011-10-29 16:11:59
lljy(½ð±Ò+4): 2011-10-30 22:30:09
wg423(·ÒëEPI+1): Â¥Ö÷·¢·Å´íÎ󣬴ú·¢ 2011-10-31 20:19:45
|
The plastic mulches are used on the ground of millions of hectares. Only in China, the areas of the mulches were two millions eight hundreds and sixty seven thousands (2,867,000) hectares in 1989, a remarkable increase compared with the year of1979, whose corresponding areas were over forty hectares. ÓжàÉÙ¶ÀÁ¢±äÁ¿£¬¾ÍÓжàÉÙÒ»½×Æ«µ¼Êý¡£ |

2Â¥2011-10-29 15:35:45
willton
ľ³æ (ÖøÃûдÊÖ)
- ·ÒëEPI: 4
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ½ð±Ò: 2749.1
- É¢½ð: 747
- ºì»¨: 4
- Ìû×Ó: 1008
- ÔÚÏß: 175.9Сʱ
- ³æºÅ: 1466375
- ×¢²á: 2011-10-29
- ÐÔ±ð: GG
- רҵ: ȼÉÕѧ
¡ï
°®ÓëÓêÏÂ(½ð±Ò+1): 2011-10-29 16:12:06
lljy(½ð±Ò+1, ·ÒëEPI+1): 2011-10-30 22:29:24
wg423(·ÒëEPI-1): Â¥Ö÷·¢·Å´íÎó 2011-10-31 20:19:37
°®ÓëÓêÏÂ(½ð±Ò+1): 2011-10-29 16:12:06
lljy(½ð±Ò+1, ·ÒëEPI+1): 2011-10-30 22:29:24
wg423(·ÒëEPI-1): Â¥Ö÷·¢·Å´íÎó 2011-10-31 20:19:37
| plastic mulch is now used in millions of hectares of soil, In china alone, over 2,867,000 hectares of plastic mulch is used in 1989, compared with 40 hectares in 1979, it's a remarkable increase. |
3Â¥2011-10-29 15:44:06
kj89
гæ (³õÈëÎÄ̳)
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ½ð±Ò: 2.5
- Ìû×Ó: 6
- ÔÚÏß: 11.6Сʱ
- ³æºÅ: 1324538
- ×¢²á: 2011-06-16
- ÐÔ±ð: GG
- רҵ: ½ðÊô½á¹¹²ÄÁÏ

4Â¥2011-10-29 20:42:09
willton
ľ³æ (ÖøÃûдÊÖ)
- ·ÒëEPI: 4
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ½ð±Ò: 2749.1
- É¢½ð: 747
- ºì»¨: 4
- Ìû×Ó: 1008
- ÔÚÏß: 175.9Сʱ
- ³æºÅ: 1466375
- ×¢²á: 2011-10-29
- ÐÔ±ð: GG
- רҵ: ȼÉÕѧ
5Â¥2011-10-30 11:05:45

6Â¥2011-10-30 22:35:11













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