] are investigated in presence of two time-correlated noises. The steady state probability distribution can be obtained by solving the Fokker-Planck equation. It is found that both the correlated-time between the white noise and the colored noise and that between the colored noises can convert the bistability to monostability while the former activates the transcription and the latter suppresses it.

Fe-doped TiO2 was prepared by a homogenous precipitation method and characterized by XRD, UV-Vis DRS. The structure and the optical properties of nano-TiO2 with different Fe doping content were studied, as well as the effect and the possible mechanics of different intensity of TiO2 particles, Fe-doped nano-TiO2 particles on the activity of HL60 leukemic cells. The influence on the activity of cells exposures in light compared with un-exposure also be analysed. As the photo sensitizers, TiO2 and Fe-doped TiO2 particles eliminated tumor cell using photodynamic therapy(PDT)under magnetic field.

Pseudomonas sp. B3-1, a wild strain isolated from soil, produced catechol from benzoate and accumulated it outside the cell. catA, a gene encodes a catechol 1,2-dioxygenase in the bioconversion of aromatic compounds, plays the central role in accumulation of catechol. Mutant of the catA gene is disrupted without blocking the transcription of downstream genes was analyzed. The result showed that the mutant had less catechol 1, 2-dioxygenase activity, only 1/3 of strain B3-1’s. The mutant produced a maximal amount of catechol (1.22 mg/ml) from 4 mg/ml of sodium benzoate after growing for 48 h. The conversion rate of benzoate to catechol was 51.5% on a molar basis.

The characteristics of working medium is one of the important factors for organic Rankine cycle.The study is based on the waste heat of power plant,7 kinds working medium are selected,include R245fa, R600, R600a, R601a, R236fa, R236ea and RC318.ORC's thermodynamic cycle characteristics are calculated based on the first law of thermodynamics,then,compared the thermal efficiency,evaporating pressure and power ratio of different working medium.Results show that R245fa and R601a as the ORC system working medium have higher thermal efficiency and power ratio,and lower evaporating pressure than other five working medium,are ideal organic working medium to recycle flue gas waste heat of power plant.Secondly,R600 as system cycle working medium also has relatively good performance,can be the appropriate choice of working medium.

Photodynamic therapy is a kind of new method of treatment for leukemia. In this thesis, we use the quantum dots CdTe as photosensitive drugs on photodynamic therapy study of leukemia with chemotherapy, in order to explore new methods. This thesis studied the Qds-PDT treatment based on CdTe on HL60 in vitro.And it also studied the effect of the inactivated leukemia HL60 tumor cells by the three antibiotics in vitro.What’s more, based on the selected quantum dot and the PDT reaction chamber, photodynamic therapy of inactivation tumor cells HL60 is carried out by using the new photosensitizer with chemotherapy in vitro.