A transformation of naphthalene-based coalescenced mesophase pitch(NMP)to mesophase microbeads was achieved by heating a mixture of NMP and fullerene(C_(60)).This is different from the conventional process of the liqu...A transformation of naphthalene-based coalescenced mesophase pitch(NMP)to mesophase microbeads was achieved by heating a mixture of NMP and fullerene(C_(60)).This is different from the conventional process of the liquid-phase carbonization of isotropic pitch to the emergence of carbon microbeads in the matrix and finally their growth to form a 100%anisotropic bulk meso-phase,but rather a reverse transformation.The effects of C_(60) loading and reaction temperature on the morphological transformation of mesophase were investigated by polarizing optical and scanning electron microscopies.The physical changes in the NMP induced by C_(60) were characterized by thermogravimetric analysis,Fourier transform infrared spectroscopy,X-ray diffractometry and Raman spectroscopy.The results show that the coalesced NMP can be converted to a spherical type at 300-320℃ with the addition of 5%C_(60),and the size of the mesophase microbeads increases with increasing temperature.Furthermore,a model is established to ex-plain the unique induction effect of C_(60) in the transformation process.This work makes the morphological transformation of MP con-trollable,and provides a new idea for the understanding and research of mesophase pitch.展开更多
[Objective] The aim was to investigate AtNHX1 gene transformation in Brassica napus L. mediated by Agrobacterium tumefaciens. [Method] By using Agrobacterium-mediated method and cre/lox plant expression vector,the tra...[Objective] The aim was to investigate AtNHX1 gene transformation in Brassica napus L. mediated by Agrobacterium tumefaciens. [Method] By using Agrobacterium-mediated method and cre/lox plant expression vector,the transformation of AtNHX1 gene of Na＋/H＋ antiporter in Brassica napus was studied. [Result] The regeneration rate of cotyledon with petiole was much higher than that of hypocotyl,thus,the cotyledon with petiole was selected as the recipient for transformation. After the cotyledon with petiole was soaked in bacterial solution （OD600=0.4） for 8-10 min,kanamycin-resistant green seeding percentage could reach 3.75%. [Conclusion] The PCR detection of kanamycin-resistant plants proved that NHX1 gene had been inserted into Brassica napus genome. And this research could provide a new way to improve the salt tolerance of Brassica napus.展开更多
AtNHX1 gene encoding the Na ^＋/H ^＋ antiport on the vacuole membrane of Arabidopsis was transferred into small bud tips of 1-3mm in length derived from immature inflorescence cultures of six genotypes of beet （ Bet...AtNHX1 gene encoding the Na ^＋/H ^＋ antiport on the vacuole membrane of Arabidopsis was transferred into small bud tips of 1-3mm in length derived from immature inflorescence cultures of six genotypes of beet （ Beta vulgaris L. ） by the infection of Agrobacterium tumefaciens and transgenic plants with improved salt-tolerance were obtained. When transgenic plants at 5-leaf stage were potted in sand and irrigated with solutions containing a range of concentrations of NaCl （171-513mM）, they showed minor symptoms of damage from salinity and better tolerance than the controls. There were considerable discrepancies of salt-tolerance between transgenic plants originated from the same genotype and also between different genotypes. After vernalization, bolting transgenic plants were enveloped with two layers of gauzes for self-pollination. T1 seedlings tolerant to 342-427mM NaCl were obtained respectively. These results revealed that it was feasible to improve salt-tolerance of beets by the introduction of AtNHX1 gene into cultured bud cells.展开更多
文摘A transformation of naphthalene-based coalescenced mesophase pitch(NMP)to mesophase microbeads was achieved by heating a mixture of NMP and fullerene(C_(60)).This is different from the conventional process of the liquid-phase carbonization of isotropic pitch to the emergence of carbon microbeads in the matrix and finally their growth to form a 100%anisotropic bulk meso-phase,but rather a reverse transformation.The effects of C_(60) loading and reaction temperature on the morphological transformation of mesophase were investigated by polarizing optical and scanning electron microscopies.The physical changes in the NMP induced by C_(60) were characterized by thermogravimetric analysis,Fourier transform infrared spectroscopy,X-ray diffractometry and Raman spectroscopy.The results show that the coalesced NMP can be converted to a spherical type at 300-320℃ with the addition of 5%C_(60),and the size of the mesophase microbeads increases with increasing temperature.Furthermore,a model is established to ex-plain the unique induction effect of C_(60) in the transformation process.This work makes the morphological transformation of MP con-trollable,and provides a new idea for the understanding and research of mesophase pitch.
基金Supported by Key Project of Nanjing Xiaozhuang University(2007NXY01)Natural Science Foundation of the Higher Education Institutions of Jiangsu Province (08KJD180011)College Student Practice and Innovation Training Program in Jiangsu Province(2009-2011)~~
文摘[Objective] The aim was to investigate AtNHX1 gene transformation in Brassica napus L. mediated by Agrobacterium tumefaciens. [Method] By using Agrobacterium-mediated method and cre/lox plant expression vector,the transformation of AtNHX1 gene of Na＋/H＋ antiporter in Brassica napus was studied. [Result] The regeneration rate of cotyledon with petiole was much higher than that of hypocotyl,thus,the cotyledon with petiole was selected as the recipient for transformation. After the cotyledon with petiole was soaked in bacterial solution （OD600=0.4） for 8-10 min,kanamycin-resistant green seeding percentage could reach 3.75%. [Conclusion] The PCR detection of kanamycin-resistant plants proved that NHX1 gene had been inserted into Brassica napus genome. And this research could provide a new way to improve the salt tolerance of Brassica napus.
文摘AtNHX1 gene encoding the Na ^＋/H ^＋ antiport on the vacuole membrane of Arabidopsis was transferred into small bud tips of 1-3mm in length derived from immature inflorescence cultures of six genotypes of beet （ Beta vulgaris L. ） by the infection of Agrobacterium tumefaciens and transgenic plants with improved salt-tolerance were obtained. When transgenic plants at 5-leaf stage were potted in sand and irrigated with solutions containing a range of concentrations of NaCl （171-513mM）, they showed minor symptoms of damage from salinity and better tolerance than the controls. There were considerable discrepancies of salt-tolerance between transgenic plants originated from the same genotype and also between different genotypes. After vernalization, bolting transgenic plants were enveloped with two layers of gauzes for self-pollination. T1 seedlings tolerant to 342-427mM NaCl were obtained respectively. These results revealed that it was feasible to improve salt-tolerance of beets by the introduction of AtNHX1 gene into cultured bud cells.
