| ²é¿´: 740 | »Ø¸´: 4 | |||
| ±¾Ìû²úÉú 1 ¸ö ·ÒëEPI £¬µã»÷ÕâÀï½øÐв鿴 | |||
lsoul24517Òø³æ (СÓÐÃûÆø)
|
[½»Á÷]
ÇóÖú·ÒëÒ»¶Î»°
|
||
|
We exploit a precipitation-redispersion mechanism for complexation of short chain polyelectrolytes with cerium oxide nanoparticles to extend their stability ranges. As synthesized, cerium oxide sols at pH 1.4 consist of monodisperse cationic nanocrystalline particles having a hydrodynamic diameter of 10 nm and a molecular weight of 400 000 g mol-1. We show that short chain uncharged poly(acrylic acid) at low pH when added to a cerium oxide sols leads to macroscopic precipitation. As the pH is increased, the solution spontaneously redisperses into a clear solution of single particles with an anionic poly(acrylic acid) corona. The structure and dynamics of cerium oxide nanosols and their hybrid polymer-inorganic complexes in solution are investigated by static and dynamic light scattering, X-ray scattering, and chemical analysis. Quantitative analysis of the redispersed sol gives rise to an estimate of 40-50 polymer chains per particle for stable suspension. This amount represents 20% of the mass of the polymer-nanoparticle complexes.This complexation adds utility to the otherwise unstable cerium oxide dispersions by extending the range of stability of the sols in terms of pH, ionic strength, and concentration |
» ²ÂÄãϲ»¶
22408 µ÷¼Á²ÄÁÏ
ÒѾÓÐ6È˻ظ´
285Çóµ÷¼Á
ÒѾÓÐ12È˻ظ´
Çóµ÷¼Á
ÒѾÓÐ6È˻ظ´
085600²ÄÁÏÓ뻯¹¤301·ÖÇóµ÷¼ÁԺУ
ÒѾÓÐ19È˻ظ´
277¹¤¿ÆÇóµ÷¼Á
ÒѾÓÐ11È˻ظ´
277Çóµ÷¼Á ÊýÒ»104·Ö
ÒѾÓÐ13È˻ظ´
304Çóµ÷¼Á
ÒѾÓÐ10È˻ظ´
336Çóµ÷¼Á£¬Ò»Ö¾Ô¸Öпƴó
ÒѾÓÐ6È˻ظ´
071000ÉúÎïѧ£¬Ò»Ö¾Ô¸ÉîÛÚ´óѧ296·Ö£¬Çóµ÷¼Á
ÒѾÓÐ3È˻ظ´
Ò»Ö¾Ô¸±±¾©»¯¹¤085600 310·ÖÇóµ÷¼Á
ÒѾÓÐ19È˻ظ´
kedaweiwei
Ìú¸Ëľ³æ (ÕýʽдÊÖ)
- ·ÒëEPI: 6
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ½ð±Ò: 7293.4
- Ìû×Ó: 530
- ÔÚÏß: 68.8Сʱ
- ³æºÅ: 607067
- ×¢²á: 2008-09-19
- ÐÔ±ð: GG
- רҵ: ²£Á§²ÄÁÏ
lsoul24517(½ð±Ò+10):ллÁË 2010-04-26 18:23
|
ÎÒÃÇÀûÓóÁµí-·ÖÉ¢»úÀí¶Ô¶ÌÁ´¾Ûµç½âÖʺÍÑõ»¯îæÄÉÃ׿ÅÁ£½øÐÐÂçºÏ£¬ÒÔÀ©´óÆäÎȶ¨·¶Î§¡£Ôڸúϳɷ´Ó¦ÖУ¬pHֵΪ1.4ʱÑõ»¯îæÈܽºÓÉÁ÷Ìåѧֱ¾¶Îª10nm£¬·Ö×ÓÖÊÁ¿Îª400 000g mol-1µÄµ¥·ÖÉ¢ÑôÀë×ÓÄÉÃ×¾§ÌåÁ£×Ó×é³É£¬ÎÒÃǵÄÑо¿ÏÔʾÔÚµÍpHʱ½«²»´øµçºÉµÄ¾Û£¨±ûÏ©Ëᣩ¶ÌÁ´¼ÓÈëµ½Ñõ»¯îæÈܽºÖÐʱ»áµ¼ÖÂÈâÑۿɼûµÄ³Áµí¡£Ëæ×ÅpHÖµÉý¸ß£¬ÈÜÒº×Ô·¢µÄ·ÖÉ¢³ÉÒ»¸ö¸ö´øÓоۣ¨±ûÏ©ËᣩÒõÀë×Ó»ùÍŵĿÅÁ£µÄÇåÒº¡£Í¨¹ý¾²Ì¬ºÍ¶¯Ì¬¹âÉ¢Éä¡¢X-ÉäÏßÑÜÉäÒÔ¼°»¯Ñ§·ÖÎö·¨Ñо¿ÁËÑõ»¯îæÈܽº¼°Óлú-ÎÞ»ú¹²»ìÎïÔÚÈÜÒºÖеĽṹºÍ¶¯Á¦Ñ§ÌØÐÔ¡£·ÖÉ¢ÈܽºµÄ¶¨Á¿·ÖÎö¸ø³öÁËÎȶ¨µÄÐü¸¡ÒºÖе¥¸ö¿ÅÁ£µÄ¾ÛºÏÎïÁ´Îª40-50¸ö¡£ÕâÒ»ÊýÁ¿¸ø³öÁ˸߷Ö×Ó-ÄÉÃ׿ÅÁ£¸´ºÏÎïÖÐ20%µÄÓлúÎïÂçºÏÁ¿¡£ÕâÖÖÂçºÏ·½Ê½Ìá¸ßÁË·ÖÉ¢Ñõ»¯îæµÄÓ¦ÓÃÐÔ£¬À©Õ¹ÁËÈܽºÔÚpH¡¢Àë×ÓÇ¿¶È¼°Å¨¶ÈµÈ·½ÃæµÄÎȶ¨ÐÔ¡£ ·ÒëµÄ²»ºÃ£¬½ö¹©²Î¿¼¡£ |

2Â¥2010-04-23 11:02:46
lastzealot
гæ (ÖøÃûдÊÖ)
¡¾ÂÒÊÀµÄ¼éÐÛ¡¿
- ·ÒëEPI: 10
- Ó¦Öú: 87 (³õÖÐÉú)
- ½ð±Ò: 2684.9
- É¢½ð: 876
- ºì»¨: 24
- Ìû×Ó: 2920
- ÔÚÏß: 212.3Сʱ
- ³æºÅ: 730090
- ×¢²á: 2009-03-24
- ÐÔ±ð: GG
- רҵ: ¸ß·Ö×Ó²ÄÁϽṹÓëÐÔÄÜ
lsoul24517(½ð±Ò+10):ллÁË 2010-04-26 18:23
|
ÎÒÃǶԺ¬ÓÐÑõ»¯îæÄÉÃ×Á£×ӵĶÌÁ´¾Ûµç½âÖʵĸ´ºÏ²ÄÁϽøÐÐÁ˳Áµí-ÔÙ·ÖÉ¢»úÀí·½ÃæµÄÑо¿£¬ÒÔÀ©´óÆäÎȶ¨·¶Î§¡£ºÏ³É³öÀ´µÄÑõ»¯îæÈܽºÔÚpH=1.4ʱº¬Óе¥·ÖÉ¢µÄ¡¢Ö±¾¶ÔÚ10nm×óÓÒÇÒ·Ö×ÓÁ¿ÔÚ400 000 g mol-1µÄÑôÀë×ÓÄÉÃ×¾§¡£½á¹û±íÃ÷¶ÌÁ´²»´øµçºÉµÄ¾Û±ûÏ©ËáÔÚµÍpHÏÂ×¢ÈëÑõ»¯îæÈܽº»áµ¼Öºê¹Û³Áµí¡£Ëæ×ÅpHÔö¼Ó£¬ÈÜÒº»áͬʱÔÙ·ÖÉ¢³ÉÈÜÓÐÒõÀë×Ó¾Û±ûÏ©Ëá»·µÄµ¥Ò»Á£×ӵijÎÇåÈÜÒº¡£Í¬Ê±£¬ÎÒÃÇͨ¹ý¾²Ì¬¡¢¶¯Ì¬¹âÉ¢Éä¡¢X¹âÉ¢ÉäºÍ»¯Ñ§·ÖÎöµÄ·½·¨Ñо¿ÁËÑõ»¯îæÄÉÃ×Èܽº¼°Æä¾ÛºÏÎï-ÎÞ»ú¸´ºÏÎïµÄ½á¹¹Ó붯Á¦Ñ§ÐÐΪ¡£ÔÙ·ÖÉ¢Äý½ºµÄ¶¨Á¿·ÖÎö±íÃ÷£¬Îȶ¨µÄÐü×ÇÒºÖÐÿ¸öÁ£×Óº¬ÓÐÔ¼40-50¸ö¾ÛºÏÎïÁ´¡£ÕâЩʾۺÏÎï-ÄÉÃ×Á£×Ó¸´ºÏÎïµÄÖÊÁ¿µÄ20%¡£ÕâÖÖ¸´ºÏÎïͨ¹ýÀ©´óÆäÈܽºµÄÎȶ¨·¶Î§£¬±ÈÈç¸Ä±äpH¡¢Àë×ÓÇ¿¶ÈºÍŨ¶ÈµÈ£¬Ôö¼ÓÁ˲»Îȶ¨Ñõ»¯îæµÄ·ÖɢЧ¹û¡£ ˮƽÓÐÏÞ£¬ÇëÄú×Ðϸ¼ì²é¡£ |
3Â¥2010-04-23 14:13:39
dubinmac
ͳæ (СÓÐÃûÆø)
- ·ÒëEPI: 1
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ½ð±Ò: 132.1
- É¢½ð: 16
- Ìû×Ó: 87
- ÔÚÏß: 12.6Сʱ
- ³æºÅ: 987189
- ×¢²á: 2010-04-01
- ÐÔ±ð: GG
- רҵ: »·¾³Î¢ÉúÎïѧ
lsoul24517(½ð±Ò+10, ·ÒëEPI+1):ллÁË 2010-04-26 18:22
|
ÎÒÃÇÀûÓóÁµíÔÙ·ÖÉ¢»úÀíÀ´ÂçºÏ¶ÌÁ´¾ÛºÏµç½âÖʺÍÑõ»¯îæÁ£×ÓÀ´À©Õ¹ËüÃǵÄÎȶ¨ÅÅÁС£ÎÄÏ×Ôø±¨µÀ¹ý£¬Ñõ»¯îæÈܽº¼ÁÔÚPH1.4ʱÓɵ¥·ÖÉ¢µÄ10nmÁ÷ÌåÁ¦Ñ§Ö±¾¶ºÍĦ¶ûÖØÁ¿Îª400000g/molµÄÄÉÃ×Á£×Ó×é³É¡£ÎÒÃÇ˵Ã÷Á˶ÌÁ´ÔÚµÍPHÖµÏÂûÓиıä¾ÛºÏÐÔ£¨¾Û±ûËᣩ£¬Ö±µ½Ìí¼ÓÁËÑõ»¯îæÈܽº¼Á²Åµ¼ÖÂÁËÈâÑۿɼûµÄ³Áµí¡£ÓÉÓÚPHÖµÔö¼Ó£¬ÈÜÒº×ÔÈ»µÄÔÙ·ÖÉ¢³Éµ¥Á£×Ó¾ßÓÐÒõÐÔµçÔεľ۱ûÏ©µÄÇ峺ÈÜÒº¡£¾²Ì¬ºÍ¶¯Ì¬¹âÉ¢É䣬XÉäÏßÉ¢ÉäºÍ»¯Ñ§·ÖÎö±»ÓÃÀ´Ñо¿Ñõ»¯îæÄÉÃ×Á£×ÓÈܽº½á¹¹ºÍ¶¯Á¦Ñ§ÒÔ¼°ËûÃÇÔÚÈÜÒºÖеÄÎÞ»ú¾ÛºÏÌåÂçºÏÎï¡£·ÖÉ¢ÈܽºµÄ¶¨Á¿·ÖÎö¸ø³öÁËÎȶ¨µÄÐü¸¡ÒºÖе¥¸ö¿ÅÁ£µÄ¾ÛºÏÎïÁ´Îª40-50¸ö¡£ËûÃǵÄÊýÁ¿Õ¼ÁËÎÞ»ú¾ÛºÏÌåÂçºÏÎïÖÊÁ¿µÄ20%¡£Õâ¸öÂçºÏÎïÌí¼ÓÁËÆäËûµÄÑõ»¯îæ·ÖÉ¢¼Á¶ÔÈܽºÔÚPHÖµ£¬Àë×ÓÇ¿¶ÈºÍŨ¶ÈÉϵÄÎȶ¨ÐÔÉ϶¼ÓÐЧ¡£ ×Ô¼º·ÒëµÄ£¬Ë®Æ½ÓÐÏÞ£¬Â¥Ö÷¿´×ŸĸİÉ~ |
4Â¥2010-04-23 15:31:47
benmao_mogu
ľ³æ (ÖøÃûдÊÖ)
- ·ÒëEPI: 51
- Ó¦Öú: 16 (СѧÉú)
- ½ð±Ò: 4930.7
- É¢½ð: 2657
- ºì»¨: 24
- Ìû×Ó: 1540
- ÔÚÏß: 198.4Сʱ
- ³æºÅ: 992763
- ×¢²á: 2010-04-09
- ÐÔ±ð: GG
- רҵ: »¯Ñ§·´Ó¦¹¤³Ì

5Â¥2010-04-24 10:24:32














»Ø¸´´ËÂ¥