Martensitic transformation behavior was studied for zirconia containing 4%~10% CeO2 (in mole fraction) by using a dilatometric method. The Ms (Martensite start temperature) decreased near linearly with increasing CeO...Martensitic transformation behavior was studied for zirconia containing 4%~10% CeO2 (in mole fraction) by using a dilatometric method. The Ms (Martensite start temperature) decreased near linearly with increasing CeO2. Different transformation modes were observed depending on the composition and cooling rate. ZrO2 containing 6% CeO2 showed isothermal transformation behavior, whereas ZrO2 containing 9% and 10% CeO2 showed athermal transformation behavior. However, ZrO2 containing 8% CeO2 showed either isothermal or athermal transformations behavior depending on the cooling rate. A TTT (Time-Temperature-Transformation) diagram was proposed for ZrO2 containing 8% CeO2.展开更多
Ab initio calculations of lattice constants, lattice stabilities of HgX(X = S, Se, Te) at different electronic temperatures(T_e) have been performed within the density functional theory(DFT). We find that the la...Ab initio calculations of lattice constants, lattice stabilities of HgX(X = S, Se, Te) at different electronic temperatures(T_e) have been performed within the density functional theory(DFT). We find that the lattice constants of HgX increase and the phonon frequencies reduce as T_e increases. Especially the transverse-acoustic(TA) phonon frequencies of HgX gradually become negative with the elevation of the electron temperature. That is to say ultrafast intense laser induces lattice instabilities of HgX and athermal melting appears for the increase of laser intensity. What is more, with the X atom number increasing, the critical electronic temperatures of HgX are decreased in sequence. This result would be helpful for understanding the athermal melting processes for femtosecond laser micromachining.展开更多
A harmonic diffractive element (HDE) is first successfully introduced to the athermal system of infrared dual band in this paper. In this system, there are only three lens and two materials, silicon and germanium. Whe...A harmonic diffractive element (HDE) is first successfully introduced to the athermal system of infrared dual band in this paper. In this system, there are only three lens and two materials, silicon and germanium. When the temperature ranges from 70℃ to 100℃ in the dual band, it can simultaneously accomplish the rectification of the longitudinal aberration in the big field of view, as well as the wave front aberration less than 1/4 wavelength. Modulation transfer function of dual band approaches or attains the diffraction limit. The calculation results show that the spec-tral properties of the HDE are between refractive and dif-fractive elements, so we can design a simple dual-band and athermal optical system by selecting the thickness and cen-tral wavelength of the HDE exactly. Compared with a con-ventional refractive optical system, this system not only re-duces the demand for high technical levels, but also has a compact structure, few elements, a high transmittance better aberrations performances and athermal character. At the same time, the use of the HDE also offers a new element for the infrared optics design.展开更多
The wavelength shifting properties and the temperature athermalization technology of fiber Bragg grating (FBG) were studied in this paper, and then two different athermalization methods were introduced. The research s...The wavelength shifting properties and the temperature athermalization technology of fiber Bragg grating (FBG) were studied in this paper, and then two different athermalization methods were introduced. The research shows that FBG with athermalization by applying the substrate with negative coefficient of thermal expansion is effective and can be used in many fields.展开更多
The specific absorption rate (SAR) characterises the energy intake from outside energy sources. Dominantly, the dosing of electromagnetic radiation uses the SAR, defining the absorbed power in unit mass, measured in W...The specific absorption rate (SAR) characterises the energy intake from outside energy sources. Dominantly, the dosing of electromagnetic radiation uses the SAR, defining the absorbed power in unit mass, measured in W/kg. Ionisation radiation creates a certain distortion in the DNA, which is the goal of radiation in oncology. The dose in this case counts the time duration of the actual SAR, and uses the absorbed energy instead of the absorbed power, measured by Gy (=J/kg). The ionising rate is the desired result, and the developed temperature is only an unwanted side effect. In the case of non-ionising radiation, the same characterisation is used for completely opposite goals. There, the direct interest is the temperature increase, and the excitation processes other than temperature increasing energy consumptions are neglected. Our objective in this work is to clarify the connections of SAR and developed temperature, and discussing the actual debates about non-ther-mal energy absorption.展开更多
The pulsed magnetic field induced martensitic transformation with isothermal and athermal kinetics in Fe-2Ni-4Mn(wt-%)alloy has been studied by means of magnetization measurements,optical microscopy and thermodymical ...The pulsed magnetic field induced martensitic transformation with isothermal and athermal kinetics in Fe-2Ni-4Mn(wt-%)alloy has been studied by means of magnetization measurements,optical microscopy and thermodymical analyses.It is shown that there exits a critical magnetic intensity for induing martensitic transformation at a given temperature above Ms.The critical magnetic field increases linearly with increasing ΔT= T-M_S.The magnetic field strongly promotes the athermal martensitic transforamtion and restrains the isothermal one.The entropy change ΔS for athermal transformation at Ms is 4.13 J/mol· K.The effect of magnetic field on martensitic transformation in Fe-21Ni-4Mn alloy is main- ly due to Zeeman effect.Lath,plate and butterfly martensities were observed under magnetic field.展开更多
The effect of electromagnetic field on plasma β endorphin in 30 patients with migraine were studied in the experiment. All subjects received a 20 minute repetitive transcranial magnetic stimulation (Frequency 10Hz, A...The effect of electromagnetic field on plasma β endorphin in 30 patients with migraine were studied in the experiment. All subjects received a 20 minute repetitive transcranial magnetic stimulation (Frequency 10Hz, Average intensity 8mT) per time, and the total experiment lasted 20 times. Before and after the experiment, the EEG and plasma β endorphin were tested. The results show that the level of plasma β endorphin in patients blood increased significantly from (73.486±26.002)mg/ml to (116.934±67.592)mg/ml (p<0.01), and the EEG average magnitude of the migraine patients were improved obviously from 41.77μV to 47.42μV.展开更多
The athermal bioeffects caused by nanosecond electromagnetic pulses with body cells was studied by using a broad band transverse EM-wave cell (BTEM CELL). The experimental system and preliminary mechanism analysis wer...The athermal bioeffects caused by nanosecond electromagnetic pulses with body cells was studied by using a broad band transverse EM-wave cell (BTEM CELL). The experimental system and preliminary mechanism analysis were presented.展开更多
Effect of electropulsing treatment(EPT) on recrystallization behavior of cold-rolled Mg alloy ZK60 strips was investigated. It was found that EPT significantly improved nucleation rate and migration ability of grain b...Effect of electropulsing treatment(EPT) on recrystallization behavior of cold-rolled Mg alloy ZK60 strips was investigated. It was found that EPT significantly improved nucleation rate and migration ability of grain boundaries, leading to accelerated recrystallization of the deformed metals at relatively low temperature. After the recrystallization induced by EPT, the average grain size of 20% rolling reduction samples decreased from 113 um to around 10 um, meanwhile the typical basal-type texture of the coldrolled sample was weakened. EPT was normally accompanied with a thermal and an athermal effects. The athermal effect played a dominated role in increasing nucleation rate, while the thermal effect promoted grain growth. A fewer recrystallized grains originated along the grain boundaries in the 10% reduction samples, while most of the recrystallization took place inside the twins in the 20% reduction samples.展开更多
文摘Martensitic transformation behavior was studied for zirconia containing 4%~10% CeO2 (in mole fraction) by using a dilatometric method. The Ms (Martensite start temperature) decreased near linearly with increasing CeO2. Different transformation modes were observed depending on the composition and cooling rate. ZrO2 containing 6% CeO2 showed isothermal transformation behavior, whereas ZrO2 containing 9% and 10% CeO2 showed athermal transformation behavior. However, ZrO2 containing 8% CeO2 showed either isothermal or athermal transformations behavior depending on the cooling rate. A TTT (Time-Temperature-Transformation) diagram was proposed for ZrO2 containing 8% CeO2.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11374217 and 11176020)
文摘Ab initio calculations of lattice constants, lattice stabilities of HgX(X = S, Se, Te) at different electronic temperatures(T_e) have been performed within the density functional theory(DFT). We find that the lattice constants of HgX increase and the phonon frequencies reduce as T_e increases. Especially the transverse-acoustic(TA) phonon frequencies of HgX gradually become negative with the elevation of the electron temperature. That is to say ultrafast intense laser induces lattice instabilities of HgX and athermal melting appears for the increase of laser intensity. What is more, with the X atom number increasing, the critical electronic temperatures of HgX are decreased in sequence. This result would be helpful for understanding the athermal melting processes for femtosecond laser micromachining.
文摘A harmonic diffractive element (HDE) is first successfully introduced to the athermal system of infrared dual band in this paper. In this system, there are only three lens and two materials, silicon and germanium. When the temperature ranges from 70℃ to 100℃ in the dual band, it can simultaneously accomplish the rectification of the longitudinal aberration in the big field of view, as well as the wave front aberration less than 1/4 wavelength. Modulation transfer function of dual band approaches or attains the diffraction limit. The calculation results show that the spec-tral properties of the HDE are between refractive and dif-fractive elements, so we can design a simple dual-band and athermal optical system by selecting the thickness and cen-tral wavelength of the HDE exactly. Compared with a con-ventional refractive optical system, this system not only re-duces the demand for high technical levels, but also has a compact structure, few elements, a high transmittance better aberrations performances and athermal character. At the same time, the use of the HDE also offers a new element for the infrared optics design.
文摘The wavelength shifting properties and the temperature athermalization technology of fiber Bragg grating (FBG) were studied in this paper, and then two different athermalization methods were introduced. The research shows that FBG with athermalization by applying the substrate with negative coefficient of thermal expansion is effective and can be used in many fields.
文摘The specific absorption rate (SAR) characterises the energy intake from outside energy sources. Dominantly, the dosing of electromagnetic radiation uses the SAR, defining the absorbed power in unit mass, measured in W/kg. Ionisation radiation creates a certain distortion in the DNA, which is the goal of radiation in oncology. The dose in this case counts the time duration of the actual SAR, and uses the absorbed energy instead of the absorbed power, measured by Gy (=J/kg). The ionising rate is the desired result, and the developed temperature is only an unwanted side effect. In the case of non-ionising radiation, the same characterisation is used for completely opposite goals. There, the direct interest is the temperature increase, and the excitation processes other than temperature increasing energy consumptions are neglected. Our objective in this work is to clarify the connections of SAR and developed temperature, and discussing the actual debates about non-ther-mal energy absorption.
文摘The pulsed magnetic field induced martensitic transformation with isothermal and athermal kinetics in Fe-2Ni-4Mn(wt-%)alloy has been studied by means of magnetization measurements,optical microscopy and thermodymical analyses.It is shown that there exits a critical magnetic intensity for induing martensitic transformation at a given temperature above Ms.The critical magnetic field increases linearly with increasing ΔT= T-M_S.The magnetic field strongly promotes the athermal martensitic transforamtion and restrains the isothermal one.The entropy change ΔS for athermal transformation at Ms is 4.13 J/mol· K.The effect of magnetic field on martensitic transformation in Fe-21Ni-4Mn alloy is main- ly due to Zeeman effect.Lath,plate and butterfly martensities were observed under magnetic field.
文摘The effect of electromagnetic field on plasma β endorphin in 30 patients with migraine were studied in the experiment. All subjects received a 20 minute repetitive transcranial magnetic stimulation (Frequency 10Hz, Average intensity 8mT) per time, and the total experiment lasted 20 times. Before and after the experiment, the EEG and plasma β endorphin were tested. The results show that the level of plasma β endorphin in patients blood increased significantly from (73.486±26.002)mg/ml to (116.934±67.592)mg/ml (p<0.01), and the EEG average magnitude of the migraine patients were improved obviously from 41.77μV to 47.42μV.
基金Project supported by the National Natural Science Foundation of China.
文摘The athermal bioeffects caused by nanosecond electromagnetic pulses with body cells was studied by using a broad band transverse EM-wave cell (BTEM CELL). The experimental system and preliminary mechanism analysis were presented.
基金supported financially by the National Natural Science Foundation of China(Nos.U1710118,51504162 and51601123)the Natural Science Foundation of Shanxi Province(Nos.2015011033 and 2015021073)+2 种基金the Research Project Supported by Shanxi Scholarship Council of China(No.2016-029)the Shanxi Province Fundamental Resources Platform of Science and Technology(No.201605D121030)the Scientific and Technological Innovation Programs for Excellent Researchers in Shanxi Province(No.201605D211015)
文摘Effect of electropulsing treatment(EPT) on recrystallization behavior of cold-rolled Mg alloy ZK60 strips was investigated. It was found that EPT significantly improved nucleation rate and migration ability of grain boundaries, leading to accelerated recrystallization of the deformed metals at relatively low temperature. After the recrystallization induced by EPT, the average grain size of 20% rolling reduction samples decreased from 113 um to around 10 um, meanwhile the typical basal-type texture of the coldrolled sample was weakened. EPT was normally accompanied with a thermal and an athermal effects. The athermal effect played a dominated role in increasing nucleation rate, while the thermal effect promoted grain growth. A fewer recrystallized grains originated along the grain boundaries in the 10% reduction samples, while most of the recrystallization took place inside the twins in the 20% reduction samples.