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51.
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Abstract The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plantsobtained whose protein content was higher than 18.5%, the highest one was 21.44%. There were 3plants obtained whose protein content was lower than 11.5%, the lowest one was 10.96%. We cansee that the whole DNA of soybean transformed into wheat via ion beam implantation can inducethe increase in wheat protein content dramatically. The result also shows that the transformationefficiency of different gene types of wheat receptor varies greatly that the implanting time has acertain effect on the efficiency of transformation. 相似文献
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54.
Xing Li Zuoqing Wang Cheng Kuei Jen Viens M. Cheeke J.D.N. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1996,43(2):331-336
Theoretical and experimental investigations of thin-walled tube acoustic wave devices for gravimetric sensing applications are presented. Integrated sensor configurations have been demonstrated by employing a sol-gel processed thin piezoelectric lead zirconate titanate (PZT) film. This was coated coaxially on stainless steel tubes and interdigital transducers (IDT) fabricated as the transmitter and receiver on the curved tube surfaces. We have observed tube waves along both the axial and circumferential directions between 1 and 6.6 MHz. We have also analyzed the mass sensitivities of different modes propagating along the tubes and shown that high mass sensitivity can be achieved by keeping the tube wall thin 相似文献
55.
An analytical method is presented for calculating the resonant frequency andQ-factor of a superconducting dielectric disk resonator operating in millimeter-wave regime with whispering-gallery mode. Resonant frequency shift due to the optical generation of quasi-particles in superconducting film is investigated as a function of photon flux. An optically tunable resonant frequency of about 500 MHz is estimated, and good agreement is found between numerical results and experimental ones. 相似文献
56.
The author presents a personal account of the search for a design procedure for Yagi-Uda antenna arrays yielding a maximum gain, or directivity if element losses are neglected. Results on current distributions in the array are briefly reviewed. The analytical approach used to achieve gain optimization by means spacing and length perturbations is sketched. By using both spacing and length perturbations, it was possible to find the optimized array analytically in a systematic way, some examples having gain increases of nearly 80%. The effects of finite dipole radius and mutual coupling were included in the theoretical treatment 相似文献
57.
许进 《西安电子科技大学学报(自然科学版)》1994,(3)
文中解决了2-重自补图的计数问题,获得了具有p个顶点的2-重自补图的数目是其中Z(A)表示置换群A的圈指标,S ̄(2)_p表示p次对称群的对群. 相似文献
58.
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60.
Mei Xuan Xu Wen Guang Liu Yun Lin Guan Zuo Peng Bi Kang De Yao 《Polymer International》1995,38(2):205-209
The phase behavior of a hybrid polymer network (HPN) composed of poly[(propylene glycol maleate)-co-(propylene glycol phthalate)] crosslinked with styrene and polyester–urethane crosslinked with methylene-bis-ortho-chloroaniline was examined. The correlation between phase separation and impact strength of the HPNs is discussed. The composition of HPNs has an effect on their properties. 相似文献