A promoter\|signal peptide probe vector of lactic acid bacteria,designated pZLB based on pMG36e has been constructed.The vector contained a reporterd gene encoding for β lactamase,which lacked a promoter and a functi...A promoter\|signal peptide probe vector of lactic acid bacteria,designated pZLB based on pMG36e has been constructed.The vector contained a reporterd gene encoding for β lactamase,which lacked a promoter and a functional signal sequence.Sau3A restriction fragments (80-400bp) from L.lactis ATCC 7962 total DNA were cloned into Bam HI site of pZLB.A lot of different size framents were selected.These fragments promoted transcription and secretion of β lactamase in L.lac tis. Sequence analysis revealed that inserted fragment in pZLBe7 contained typical promoter,SD sequence and atypical signal sequence.展开更多
Intrinsic carrier transport properties of single-walled carbon nanotubes have been probed by two parallel methods on the same individual tubes： The contactless dielectric force microscopy （DFM） technique and the co...Intrinsic carrier transport properties of single-walled carbon nanotubes have been probed by two parallel methods on the same individual tubes： The contactless dielectric force microscopy （DFM） technique and the conventional field-effect transistor （FET） method. The dielectric responses of SWNTs are strongly correlated with electronic transport of the corresponding FETs. The DC bias voltage in DFM plays a role analogous to the gate voltage in FET. A microscopic model based on the general continuity equation and numerical simulation is built to reveal the link between intrinsic properties such as carrier concentration and mobility and the macroscopic observable, i.e. dielectric responses, in DFM experiments. Local transport barriers in nanotubes, which influence the device transport behaviors, are also detected with nanometer scale resolution.展开更多
文摘A promoter\|signal peptide probe vector of lactic acid bacteria,designated pZLB based on pMG36e has been constructed.The vector contained a reporterd gene encoding for β lactamase,which lacked a promoter and a functional signal sequence.Sau3A restriction fragments (80-400bp) from L.lactis ATCC 7962 total DNA were cloned into Bam HI site of pZLB.A lot of different size framents were selected.These fragments promoted transcription and secretion of β lactamase in L.lac tis. Sequence analysis revealed that inserted fragment in pZLBe7 contained typical promoter,SD sequence and atypical signal sequence.
文摘Intrinsic carrier transport properties of single-walled carbon nanotubes have been probed by two parallel methods on the same individual tubes： The contactless dielectric force microscopy （DFM） technique and the conventional field-effect transistor （FET） method. The dielectric responses of SWNTs are strongly correlated with electronic transport of the corresponding FETs. The DC bias voltage in DFM plays a role analogous to the gate voltage in FET. A microscopic model based on the general continuity equation and numerical simulation is built to reveal the link between intrinsic properties such as carrier concentration and mobility and the macroscopic observable, i.e. dielectric responses, in DFM experiments. Local transport barriers in nanotubes, which influence the device transport behaviors, are also detected with nanometer scale resolution.
