A fully automated atomic force microscope(AFM)is presented.The mechanical motion of the AFM stage was controlled by three steppers.The fine motion of the AFM was controlled by an MCL one-axis piezo plate.A32.768kHz cr...A fully automated atomic force microscope(AFM)is presented.The mechanical motion of the AFM stage was controlled by three steppers.The fine motion of the AFM was controlled by an MCL one-axis piezo plate.A32.768kHz crystal tuning fork(TF)was used as the transducer with a probe attached.An acoustic sensor was used to measure the interactions between the probe and the sample.An SR850lock-in amplifier was used to monitor the TF signals.An additional lock-in amplifier was used to monitor the acoustic signal.A field programmable gate array(FPGA)board was used to collect the data in automatic mode.The main controller was coded with LabVIEW,which was in charge of Z-axis scan,signal processing and data visualization.A manual mode and an automatic mode were implemented in the controller.Users can switch the two modes at any time during the operation.This AFM system showed several advantages during the test operations.It is simple,flexible and easy to use.展开更多
A new kind of glass-ceramic phosphor, which contains crystalline phases with green emissions, is explored. The glassceramic is prepared through semi-melt-quenching procedure with a nominal composition of (Ca0.99Eu0.0...A new kind of glass-ceramic phosphor, which contains crystalline phases with green emissions, is explored. The glassceramic is prepared through semi-melt-quenching procedure with a nominal composition of (Ca0.99Eu0.01)3Si2O7. The greenemitting crystals are precipitated and identified to be β-Ca2SiO4: Eu2+ which is responsible for 510 nm-peaked much broader band emissions holding at 1550 ℃ for half an hour. In terms of the available light scattering theory, the appearance of opaque is discussed by closely associating with size and morphology of luminous β-Ca2SiO4 crystalline phase in glass.展开更多
文摘A fully automated atomic force microscope(AFM)is presented.The mechanical motion of the AFM stage was controlled by three steppers.The fine motion of the AFM was controlled by an MCL one-axis piezo plate.A32.768kHz crystal tuning fork(TF)was used as the transducer with a probe attached.An acoustic sensor was used to measure the interactions between the probe and the sample.An SR850lock-in amplifier was used to monitor the TF signals.An additional lock-in amplifier was used to monitor the acoustic signal.A field programmable gate array(FPGA)board was used to collect the data in automatic mode.The main controller was coded with LabVIEW,which was in charge of Z-axis scan,signal processing and data visualization.A manual mode and an automatic mode were implemented in the controller.Users can switch the two modes at any time during the operation.This AFM system showed several advantages during the test operations.It is simple,flexible and easy to use.
基金supported by the National Natural Science Foundation of China(Nos.50872091 and 21076161)the Key Discipline of Materials Physics and Chemistry of Tianjin(Nos.2006ZD30 and 10SYSYJC28100)
文摘A new kind of glass-ceramic phosphor, which contains crystalline phases with green emissions, is explored. The glassceramic is prepared through semi-melt-quenching procedure with a nominal composition of (Ca0.99Eu0.01)3Si2O7. The greenemitting crystals are precipitated and identified to be β-Ca2SiO4: Eu2+ which is responsible for 510 nm-peaked much broader band emissions holding at 1550 ℃ for half an hour. In terms of the available light scattering theory, the appearance of opaque is discussed by closely associating with size and morphology of luminous β-Ca2SiO4 crystalline phase in glass.