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Introducing Bt Gene Into Maize With Ovary Injection 总被引:1,自引:0,他引:1
It is reported here that Bt toxin gene has been successfully transferred into maize inbred line by ovary injection for the first time both at home and abroad. One transgenic plant (To) has been confirmed by Southern blotting and PCR test, and 71 progenies (T1) from T0 have been obtained through self-pollination. Of these 71 progenies, seven plants demonstrated positive results in the PCR test; four were used to feed Asian corn borer, and certain effect of insect-resistance was observed. The experiments on the ovary injection in Hainan Province have also been repeated, thus providing new chance to the application of genetic engineering to the maize improvement. 相似文献
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Time-dependent density-functional theory(TDDFT)has been applied to calculate the electronic structure and second-order nonlinear optical(NLO) properties of some organic molecules.The two-dimensional(2-D)charge transfer charateristics of calculated molecules were studied and compared with corresponding experimental results.All the theoretical results agree well with the measurement.For 2-D molecule with two-fold symmetry,the dominant charge transfer is off-diagonal,while for three-fold symmetry 2-D molecule,the dominant charge transfer is not only between branches and central group but also among branches. 相似文献
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The genomie DNA of CaMV (Xinjiang isolate) was mapped on the virion DNA with anumber of restriction endonueleases by double digestions and partial digestions of one-end~(32)P-labelled fragments. It contained the unique sites of BglI, SalI and XhoI. BamHI andHhaI each cut it at two sites, EeoRI at five sites (three of which were located), Hpa Ⅱ atseven sites, BglⅡ at eight sites, and HaeⅢ at ten sites. The sites of all the enzymes usedabove, as well as HindⅢ which cut at ton sites were also mapped on the cloned CaMVDNA. Virion DNA and cloned viral DNA gave the same results in the number and locationof cleavage sites of the restriction enzymes tested on both DNAs. Like most of the otherisolates, CaMV-Xinjiang isolate has three single-stranded discontinuities. From the diges-tion patterns of SalI, XhoI, EcoRI and HhaI, it is concluded that the restriction map ofCaMV-XJ genome is closely related to that of BKMV isolate from East Germany. 相似文献
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莽朝永 《原子与分子物理学报》2014,31(6)
采用梯度校正的密度泛函理论方法,计算了云南松松塔中分离的2种新木脂素的绝对结构为7S,8R的手性结构、电子吸收光谱、电子圆二色谱、红外振动光谱和振动圆二色谱,计算值与实验值相符. 分子轨道和振动模式分析,两种新木质素具有相似的手性光谱. 电荷密度转移对电子圆二色谱具有主要贡献;而振动圆二色谱主要源于分子骨架运动. 相似文献
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过渡金属体系非线性光学性质计算的ECP基组研究 总被引:1,自引:1,他引:0
有效核势(ECP)方法是计算含有过渡金属体系的电子结构及物理性质的有效方法. 本文比较了一系列典型的ECP基组对计算含过渡金属体系非线性光学性质精度的影响. 分别在HF, MP2和DFT理论水平上对过渡金属元素使用不同的ECP基组, 计算了几个过渡金属有机化合物的静态一阶超极化率β0. 研究结果表明: 使用有效核势计算含过渡金属体系时, 核电子的选取是提高计算精度的前提, ns和np电子应该和nd电子一同作为价电子处理; 对于重原子, 必须考虑自旋-轨道耦合相对论效应. 经过综合评估, 认为使用Stuttgart/Dresden赝势的ECP基组, MHF, 在计算含有过渡金属体系非线性光学性质方面是比较好的基组; Stuttgart RSC 1997和SBKJC VDZ相对而言是较好的基组; 基组Lanl2dz, Hay-Wadt MB (n+1)和Hay-Wadt VDZ (n+1)由于没有考虑自旋-轨道耦合, 计算精确度次之; 而基组CRENBL和CRENBS计算的偏差要大一些, 尤其是CRENBS基组由于价电子选择得太少而导致与实验值的偏差最大. 相似文献