The 5＇-nontranslated leader（omega sequence） of Tobacco mosaic virus（TMV） was used as a translational enhancer sequence in the expression of the hepatitis B surface antigen（HBsAg） gene in transgenic ginseng call...The 5＇-nontranslated leader（omega sequence） of Tobacco mosaic virus（TMV） was used as a translational enhancer sequence in the expression of the hepatitis B surface antigen（HBsAg） gene in transgenic ginseng callus cultures. The adr subtype HBsAg gene was placed under the control of the Cauliflower mosaic virus（CaMV） 35S promoter linking to the TMV leader sequence. The antisense omega sequence was used in a control construct. The resulting constructs cloned in the binary vector pBI121 were used to transform the ginseng callus tissue via the Agrobacterium-mediated procedure. The integration and expression of the HBsAg gene were evaluated by PCR and western blot, respectively. Enzyme-linked immunoassays（ELISA） using a monoclonal antibody directed against human serum-derived HBsAg revealed a three to four-fold enhanced expression of HBsAg in ginseng cells conferred by the TMV omega element.展开更多
We fabricated a c−axis aligned Sr_(0.6)K_(0.4)Fe_(2)As_(2)superconductor using a two−step magnetic field procedure.The effect of the magnetic fields on the structure and superconducting properties of Sr_(0.6)K_(0.4)Fe...We fabricated a c−axis aligned Sr_(0.6)K_(0.4)Fe_(2)As_(2)superconductor using a two−step magnetic field procedure.The effect of the magnetic fields on the structure and superconducting properties of Sr_(0.6)K_(0.4)Fe_(2)As_(2) is investigated using x−ray diffraction and magnetic measurements.The degree of orientation of the samples is about 0.39 for the c axis and 0.51 for ab-plane orientation,as evaluated from the Lotgering factor of x-ray diffraction.This technology may be useful in a variety of potential applications,including preparing iron-based superconducting bulks and wires with high critical currents.展开更多
文摘基于传热和压降的耦合作用,针对R744/R290(20/80)和R125/R290(25/75)混合工质逆流换热冷凝器建立基于熵产最小化的管长优化数学模型,并结合Cavallini凝换热性能评价指标PEI(performance evaluation index)和温度惩罚因子TTP(total temperature penalization),得到了混合工质PEI与传热系数α之间的函数关系,具体分析了管径、冷凝温度和被动压降对管长优化结果的影响。研究表明,制冷剂饱和温度降为制冷剂与壁面之间传热驱动温差的0.6倍,高压工质R744/R290(20/80)(临界温度低的工质)的PEI值更小,冷凝换热性能更优,同时小管径的冷凝器最优管长更小,且最优管长随随着冷凝温度的增大而增大,随着被动压降的增加而减小。
基金Science and Technology Development Planning Foundation of Jilin Province, China(No. 20030405)
文摘The 5＇-nontranslated leader（omega sequence） of Tobacco mosaic virus（TMV） was used as a translational enhancer sequence in the expression of the hepatitis B surface antigen（HBsAg） gene in transgenic ginseng callus cultures. The adr subtype HBsAg gene was placed under the control of the Cauliflower mosaic virus（CaMV） 35S promoter linking to the TMV leader sequence. The antisense omega sequence was used in a control construct. The resulting constructs cloned in the binary vector pBI121 were used to transform the ginseng callus tissue via the Agrobacterium-mediated procedure. The integration and expression of the HBsAg gene were evaluated by PCR and western blot, respectively. Enzyme-linked immunoassays（ELISA） using a monoclonal antibody directed against human serum-derived HBsAg revealed a three to four-fold enhanced expression of HBsAg in ginseng cells conferred by the TMV omega element.
基金by the National Basic Research Program of China under Grant No 2011CBA00105the National Natural Science Foundation of China under Grant Nos 51002150 and 51025726。
文摘We fabricated a c−axis aligned Sr_(0.6)K_(0.4)Fe_(2)As_(2)superconductor using a two−step magnetic field procedure.The effect of the magnetic fields on the structure and superconducting properties of Sr_(0.6)K_(0.4)Fe_(2)As_(2) is investigated using x−ray diffraction and magnetic measurements.The degree of orientation of the samples is about 0.39 for the c axis and 0.51 for ab-plane orientation,as evaluated from the Lotgering factor of x-ray diffraction.This technology may be useful in a variety of potential applications,including preparing iron-based superconducting bulks and wires with high critical currents.
