Photoionization/dissociation of 1,2 propylene oxide are performed by using a time of flight mass spectrometer(TOF MS) with vacuum ultraviolet photons from Hefei synchrotron radiation source. The photoionization TOF ma...Photoionization/dissociation of 1,2 propylene oxide are performed by using a time of flight mass spectrometer(TOF MS) with vacuum ultraviolet photons from Hefei synchrotron radiation source. The photoionization TOF mass spectrum and photoionization efficiency(PIE) curves of fragment ions are measured.The appearance potentials(AP) of these ions are obtained from their PIE curves. From these data, the formation enthalpies of the observed ions have been evaluated, and their possible channels have been analyzed. The mechanism of dissociative photoionization of 1,2 propylene oxide has been discussed.展开更多
Bubble formation in an opposite-flowing T-shaped microchannel with 40 μm in depth and 120 μm in width was real-time visualized and investigated experimentally by means of a high speed camera. N2 bubbles were generat...Bubble formation in an opposite-flowing T-shaped microchannel with 40 μm in depth and 120 μm in width was real-time visualized and investigated experimentally by means of a high speed camera. N2 bubbles were generated in glycerol-water mixtures with different concentrations of surfactant sodium dodecyl sulfate (SDS). And the images were captured by the high speed camera linked to a computer. Results indicated that the bubble formation process can be distinguished into three consecutive stages, i.e., expansion, collapse and pinching off. The bubble size decreases with the increase of liquid flow rate and viscosity of liquid phase as well as the decrease of gas flow rate. The surface tension of the liquid phase has no measurable influence on the bubble size. Moreover, a new approach to predicting the size of bubbles formed in the T-shaped microchannel is proposed. And the predicted values agree well with the experimental data.展开更多
A real time algorithm is presented here to recognize and analyze 8 channel simultaneous electro cardiograph(ECG). The algorithm transforms 8 channel simultaneous ECG into three orthogonal vectors and spatial veloc...A real time algorithm is presented here to recognize and analyze 8 channel simultaneous electro cardiograph(ECG). The algorithm transforms 8 channel simultaneous ECG into three orthogonal vectors and spatial velocity first, then forms the spatial velocity sample, and uses this spatial velocity sample to recognize each beat. The algorithm computes the averaged parameters by using averaged spatial velocity and the averaged ECG and the current parameters by using the current beat period and current width of QRS. The algorithm can recognize P, QRS and T onsets and ends of simultaneous 12 lead ECG precisely, and some arrhythmias such as premature ventricular beat, ventricular escape beat, R on T, bigeminy, trigeminy. The algorithm software works well on a real 8 channel ECG system and meets the demands of designing.展开更多
In this paper,a microscopic phase-field model was used to investigate the effect of the oriented diffusion channel and the phases' effect mechanism for the Ni75Al6.0V19.0 alloy during a phase transformation proces...In this paper,a microscopic phase-field model was used to investigate the effect of the oriented diffusion channel and the phases' effect mechanism for the Ni75Al6.0V19.0 alloy during a phase transformation process.A diffusion channel of V was formed in the [100] direction.The oriented growth of DO22 in this direction,when an elastic misfit stress field existed,forced Al to form a diffusion channel next to DO22,resulting in L12-oriented growth.With an increase in stress,the oriented growth increased initially and then decreased.At a higher stress,the average values of the occupation probability for V atoms became constant later while Al atoms earlier.展开更多
Our knowledge of the physiology of ion channels has increased tremendously during the past 20 years because of the advances of the single-channel recording and molecular cloning techniques. More than 50 different iden...Our knowledge of the physiology of ion channels has increased tremendously during the past 20 years because of the advances of the single-channel recording and molecular cloning techniques. More than 50 different identified potassium channels have already been found.1,2 They are distributed ubiquitously in wide variety of cells including airway smooth muscle （ASM） cells and inflammatory cells in airway such as eosinophils, basophils, macrophages and so on.3 Several types of K+ channels have been identified in ASM cells, e.g., a large-conductance, voltgage-dependent Ca2+-activated K+ channel(BKCa), a voltage-dependent delayed-rectifier K+ channel（Kv）, and an ATP-sensitve K+ channel(KATP).1 In such excitable cells,展开更多
文摘Photoionization/dissociation of 1,2 propylene oxide are performed by using a time of flight mass spectrometer(TOF MS) with vacuum ultraviolet photons from Hefei synchrotron radiation source. The photoionization TOF mass spectrum and photoionization efficiency(PIE) curves of fragment ions are measured.The appearance potentials(AP) of these ions are obtained from their PIE curves. From these data, the formation enthalpies of the observed ions have been evaluated, and their possible channels have been analyzed. The mechanism of dissociative photoionization of 1,2 propylene oxide has been discussed.
基金Supported by National Natural Science Foundation of China (No. 20876107)Open Project of State Key Laboratory of Chemical Engineering (No. SKL-ChE-08B06) Program of Introducing Talents of Discipline to Universities (No. B06006)
文摘Bubble formation in an opposite-flowing T-shaped microchannel with 40 μm in depth and 120 μm in width was real-time visualized and investigated experimentally by means of a high speed camera. N2 bubbles were generated in glycerol-water mixtures with different concentrations of surfactant sodium dodecyl sulfate (SDS). And the images were captured by the high speed camera linked to a computer. Results indicated that the bubble formation process can be distinguished into three consecutive stages, i.e., expansion, collapse and pinching off. The bubble size decreases with the increase of liquid flow rate and viscosity of liquid phase as well as the decrease of gas flow rate. The surface tension of the liquid phase has no measurable influence on the bubble size. Moreover, a new approach to predicting the size of bubbles formed in the T-shaped microchannel is proposed. And the predicted values agree well with the experimental data.
文摘A real time algorithm is presented here to recognize and analyze 8 channel simultaneous electro cardiograph(ECG). The algorithm transforms 8 channel simultaneous ECG into three orthogonal vectors and spatial velocity first, then forms the spatial velocity sample, and uses this spatial velocity sample to recognize each beat. The algorithm computes the averaged parameters by using averaged spatial velocity and the averaged ECG and the current parameters by using the current beat period and current width of QRS. The algorithm can recognize P, QRS and T onsets and ends of simultaneous 12 lead ECG precisely, and some arrhythmias such as premature ventricular beat, ventricular escape beat, R on T, bigeminy, trigeminy. The algorithm software works well on a real 8 channel ECG system and meets the demands of designing.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51075335, 10902086, 50875217)the NPU Foundation for Fundamental Research (Grant No. JC201005)the Doctorate Foundation of Northwestern Polytechnical University (Grant No.CX201007)
文摘In this paper,a microscopic phase-field model was used to investigate the effect of the oriented diffusion channel and the phases' effect mechanism for the Ni75Al6.0V19.0 alloy during a phase transformation process.A diffusion channel of V was formed in the [100] direction.The oriented growth of DO22 in this direction,when an elastic misfit stress field existed,forced Al to form a diffusion channel next to DO22,resulting in L12-oriented growth.With an increase in stress,the oriented growth increased initially and then decreased.At a higher stress,the average values of the occupation probability for V atoms became constant later while Al atoms earlier.
文摘Our knowledge of the physiology of ion channels has increased tremendously during the past 20 years because of the advances of the single-channel recording and molecular cloning techniques. More than 50 different identified potassium channels have already been found.1,2 They are distributed ubiquitously in wide variety of cells including airway smooth muscle （ASM） cells and inflammatory cells in airway such as eosinophils, basophils, macrophages and so on.3 Several types of K+ channels have been identified in ASM cells, e.g., a large-conductance, voltgage-dependent Ca2+-activated K+ channel(BKCa), a voltage-dependent delayed-rectifier K+ channel（Kv）, and an ATP-sensitve K+ channel(KATP).1 In such excitable cells,
