[目的]研究苦参碱在温度诱导的EOPO/无机盐体系中的分配行为。[方法]利用紫外分光光度计对苦参碱进行定性定量测量。利用双水相分配技术研究不同的EOPO的分子量(SDP28、SDP30,SDP35)、不同种类的盐(KH2PO4、K2HPO4.3H2O、Na2SO4、NH4C l...[目的]研究苦参碱在温度诱导的EOPO/无机盐体系中的分配行为。[方法]利用紫外分光光度计对苦参碱进行定性定量测量。利用双水相分配技术研究不同的EOPO的分子量(SDP28、SDP30,SDP35)、不同种类的盐(KH2PO4、K2HPO4.3H2O、Na2SO4、NH4C l)对双水相分配的影响,并利用正交试验确定最佳的分离纯化的条件。[结果]苦参碱在EOPO 3种分子量和3种盐温度诱导双水相的分配特性研究表明,EOPO分子量为SDP28时,最大收率为77.59%,盐为K2HPO4时,最大收率为77.59%,分离效果最好。L9(33)正交试验研究表明,最佳的分离条件为:K2HPO4用量2 g;水量10 m l;SDP28用量15 m l时,最大收率为86.39%。[结论]盐的种类对双水相的分配行为影响最大。展开更多
Auto cascade refrigeration(ACR) cycle with phase separators is widely used in the cryogenic system. The composition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of ...Auto cascade refrigeration(ACR) cycle with phase separators is widely used in the cryogenic system. The composition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of infinite volume of phase separator, ACR system with one phase separator is simulated in this paper. The variation of refrigerant composition under different valves opening is obtained. A related experimental system is set up to verify the variation. The result shows that when the valve opening connected to the evaporator increases or the valve opening under the phase separator decreases, the low-boiling component concentration of the working mixture passing through the compressor and condenser increases, while the high-boiling component concentration decreases. Furthermore, the variations of condensation pressure and evaporation pressure under different valves opening are also observed. This paper is helpful to deepen the understanding of ACR system.展开更多
The structural, electronic and magnetic properties of La0.55Ca0.45MnO3 were measured. A rapid change of lattice parameters appeared around 190 K associated with the az2 orbital ordering and charge ordering （CO） stat...The structural, electronic and magnetic properties of La0.55Ca0.45MnO3 were measured. A rapid change of lattice parameters appeared around 190 K associated with the az2 orbital ordering and charge ordering （CO） states that were reflected by both magnetization and resistivity. Great difference of magnetizations between the field-cooling （FC） and zero-field-cooling （ZFC） modes below the charge ordering temperature Too in high magnetic field （H〉4 T） was clearly seen. A field of 5 T （threshold field） is sufficient to completely destroy the antiferromagnetic （AFM） CO state for FC mode in magnetization while it is not the case for ZFC mode. A much larger field （larger than 10 T from ZFC resistivity data） is needed to destroy the CO state for ZFC mode. This could be explained by the coexistence and transformation of two phases reported by Huang et al. For ZFC mode, with increasing H, Tco gradually moves to low temperature regime and the relationship between the critical field Hc （0） to destroy CO state and Tco conforms to a power law Hc = Hc（0）（1 - T/Tco（0））^γ, where Hc （0） is the critical field to destroy the CO state at 0 K, and Too （0） is the CO temperature in zero field.展开更多
文摘[目的]研究苦参碱在温度诱导的EOPO/无机盐体系中的分配行为。[方法]利用紫外分光光度计对苦参碱进行定性定量测量。利用双水相分配技术研究不同的EOPO的分子量(SDP28、SDP30,SDP35)、不同种类的盐(KH2PO4、K2HPO4.3H2O、Na2SO4、NH4C l)对双水相分配的影响,并利用正交试验确定最佳的分离纯化的条件。[结果]苦参碱在EOPO 3种分子量和3种盐温度诱导双水相的分配特性研究表明,EOPO分子量为SDP28时,最大收率为77.59%,盐为K2HPO4时,最大收率为77.59%,分离效果最好。L9(33)正交试验研究表明,最佳的分离条件为:K2HPO4用量2 g;水量10 m l;SDP28用量15 m l时,最大收率为86.39%。[结论]盐的种类对双水相的分配行为影响最大。
基金Supported by the China Postdoctoral Science Foundation(2014M552195)the State Key Laboratory Foundation of Subtropical Building,South China University of Technology(2013ZC13)the Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization,South China University of Technology(2013A061401005)
文摘Auto cascade refrigeration(ACR) cycle with phase separators is widely used in the cryogenic system. The composition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of infinite volume of phase separator, ACR system with one phase separator is simulated in this paper. The variation of refrigerant composition under different valves opening is obtained. A related experimental system is set up to verify the variation. The result shows that when the valve opening connected to the evaporator increases or the valve opening under the phase separator decreases, the low-boiling component concentration of the working mixture passing through the compressor and condenser increases, while the high-boiling component concentration decreases. Furthermore, the variations of condensation pressure and evaporation pressure under different valves opening are also observed. This paper is helpful to deepen the understanding of ACR system.
基金supported by the National Natural Science Foundation of China (Grant No. 50772111)the 211 Project of Anhui University (Grant No. 06130221)
文摘The structural, electronic and magnetic properties of La0.55Ca0.45MnO3 were measured. A rapid change of lattice parameters appeared around 190 K associated with the az2 orbital ordering and charge ordering （CO） states that were reflected by both magnetization and resistivity. Great difference of magnetizations between the field-cooling （FC） and zero-field-cooling （ZFC） modes below the charge ordering temperature Too in high magnetic field （H〉4 T） was clearly seen. A field of 5 T （threshold field） is sufficient to completely destroy the antiferromagnetic （AFM） CO state for FC mode in magnetization while it is not the case for ZFC mode. A much larger field （larger than 10 T from ZFC resistivity data） is needed to destroy the CO state for ZFC mode. This could be explained by the coexistence and transformation of two phases reported by Huang et al. For ZFC mode, with increasing H, Tco gradually moves to low temperature regime and the relationship between the critical field Hc （0） to destroy CO state and Tco conforms to a power law Hc = Hc（0）（1 - T/Tco（0））^γ, where Hc （0） is the critical field to destroy the CO state at 0 K, and Too （0） is the CO temperature in zero field.
