The effect of external constraints on Li diffusion in high-capacity Li-ion battery electrodes is investigated using a coupled finite deformation theory. It is found that thinfilm electrodes on rigid substrates experie...The effect of external constraints on Li diffusion in high-capacity Li-ion battery electrodes is investigated using a coupled finite deformation theory. It is found that thinfilm electrodes on rigid substrates experience much slower diffusion rates compared with free-standing films with the same material properties and geometric dimensions. More importantly, the study reveals that mechanical driving forces tend to retard diffusion in highly-constrained thin films when lithiation-induced softening is considered, in contrast to the fact that mechanical driving forces always enhance diffusion when deformation is fully elastic. The results provide further proof that nano-particles are a better design option for nextgeneration alloy-based electrodes compared with thin films.展开更多
Ferromagnetic Ni-Mn-Ga films were fabricated by depositing on MgO （001） substrates at temperatures from 673 K to 923 K. Microstructure, crystal structure, martensitic transformation behavior, and magnetic properties...Ferromagnetic Ni-Mn-Ga films were fabricated by depositing on MgO （001） substrates at temperatures from 673 K to 923 K. Microstructure, crystal structure, martensitic transformation behavior, and magnetic properties of the films were studied. With increasing deposition temperature, the surface morphology of the films transforms from granular to continu- ous. The martensitic transformation temperature is not dependent on deposition temperature; while transformation behavior is affected substantially by deposition temperature. X-ray analysis reveals that the film deposited at 873 K has a 7M marten- site phase, and its magnetization curve provides a typical step-increase, indicating the occurrence of magnetically induced reorientation （MIR）. In situ magnetic domain structure observation on the film deposited at 873 K reflects that the marten- sitic transformation could be divided into two periods： nucleation and growth, in the form of stripe domains. The MIR occurs at the temperature at which martensitic transformation starts, and the switching field increases with the decrease of temperature due to damped thermal activation. The magnetically induced martensitic transformation is related to the difference of magnetization between martensite and austenite. A shift of martensite temperature of dT/dH = 0.43 K/T is observed, consistent with the theoretical value, 0.41 K/T.展开更多
<strong>Objective</strong><span><span><span style="font-family:""><span style="font-family:Verdana;"><strong>:</strong> To compare the effective...<strong>Objective</strong><span><span><span style="font-family:""><span style="font-family:Verdana;"><strong>:</strong> To compare the effectiveness, safety and client acceptability of concurrent application of transcervical Foley catheter with vaginal ISMN-sustained release (SR) 60 mg tablet versus transcervical Foley catheter alone for pre-induction cervical ripening in women who are undergoing Vaginal birth after C-section (VBAC). </span><b><span style="font-family:Verdana;">Method: </span></b><span style="font-family:Verdana;">A prospective single blind randomized control study w</span></span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">as carried out including 110 pregnant women who had unfavorable cervix (MBS less than 6) at 40 weeks and 3 days of gestation. The two groups received either the trans-cervical foley catheter with a vaginal ISMN 60 mg sustained release (SR) tablet on 40 weeks and 3 days (Treatment arm 1, n = 57), or trans-cervical Foley alone on 40 weeks and 3 days (Treatment arm 2, n = 53). </span><b><span style="font-family:Verdana;">Results</span></b><span style="font-family:Verdana;">: At 40 weeks + 3 days gestation</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">, </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">the mean age, mean parity and the mean modified Bishop Score (MBS) were comparable among the two treatment groups. Majority (n = 98, 89.1%) remained without spontaneously establishing labour at 24 hours of intervention. The difference in mean MBS at 40 weeks + 4 days (24-hours following the intervention) in the two groups was statistically not significant (P > 0.05). The group who received concurrent ISMN vaginal tablets achieved a higher number of successful VBACs (n = 33, 62.3%) over the group who received the Foley catheter only method (n = 29, 50.9%)</span></span></span><span 展开更多
The dislocation structure of specimens of a duplex stainless steel with precharged hydrogen has been investigated by transmission electron microscopy.The result showed the hydrogen acti- vated dislocation source on ph...The dislocation structure of specimens of a duplex stainless steel with precharged hydrogen has been investigated by transmission electron microscopy.The result showed the hydrogen acti- vated dislocation source on phase boundaries of ferrite/austenite and makes certain dislocations in austenite grains move.The dislocation appearances in each phase in specimens uncharged with hydrogen have been given for comparison.展开更多
This paper focuses on data processing for incomplete measurement of trajectory (IMT) in aerospace measurement and control. The IMT means that the principal equipment loses the measured data during some intervals so th...This paper focuses on data processing for incomplete measurement of trajectory (IMT) in aerospace measurement and control. The IMT means that the principal equipment loses the measured data during some intervals so that trajectory parameters (position, velocity, etc.) cannot be determined independently. Based on a joint model for trajectory estimation with reduced parameter, a fusion way is put forth by making full use of measured data from auxiliary equipment with lower precision. In the superposition intervals of measurement between principal and auxiliary equipment, the technique of diagnosing and estimating system errors is applied to improving the estimate precision of trajectory parameters (TP) and determining the precision after data fusion. In practical test, this method operates so successfully that it can not only provide complete TP but improve their precision remarkably. Meanwhile, this way is also applicable to other problems of incomplete measurement.展开更多
Laser-in duced breakdown spectroscopy(LIBS),firstly proposed in 1962 as Brech and Cross[I]successfully detected the plasma emission induced by a ruby laser,has attracted more and more attention in both academia and in...Laser-in duced breakdown spectroscopy(LIBS),firstly proposed in 1962 as Brech and Cross[I]successfully detected the plasma emission induced by a ruby laser,has attracted more and more attention in both academia and industry due to its unique analytical features such as little or no sample preparation,simultaneous multi-elemental analysis,and remote sensing etc[2-4].Restrained from the highcost and poor reliability of instruments back then,the research popularity of LIBS declined quickly after a few years of initial mania of LIBS study.Since the 1990s,benefiting from the significant development of the hardware setups including laser,spectrometer,and ICCD,the'LIBS fever,re-emerged with continuous progress achieved in various applications as well as fundamental studies for the past two decades.In 2004,James D Winefordner,a prestigious an alytical scientist,crowned LIBS as a'future superstar5 for chemical analysis[5],marking the great potential of LIBS.However,on the way of fully commercialization and industrialization,LIBS is facing three big challenges:(1)to improve the quantitative analysis performance,particularly the repeatability and reproducibility performance;(2)to reduce the instrumental cost;(3)to improve the long-term stability and robustness for industrial applications.To finally transform LIBS from'future superstar,to'superstar5,joint effort of worldwide LIBS community is needed[6].展开更多
The performance of functional materials and specifically energy-related functional materials,such as fuel cells,solar cells,batteries and catalysts depends on the their local,nanoscale properties.However,heterogeneiti...The performance of functional materials and specifically energy-related functional materials,such as fuel cells,solar cells,batteries and catalysts depends on the their local,nanoscale properties.However,heterogeneities in the phase,structure and composition of these functional materials makes it difficult to directly monitor and identify the influence of local physicochemical parameters on their global functionality.In this review we will discuss recent developments in the field of IR nanospectroscopy that enables the extraction of detailed chemical information at the nanoscale and the identification of nanoscale properties that influence the global performances of functional materials.Specifically,we will discuss the ways by which infrared (IR) nanospectroscopy techniques,namely photo thermal induced resonance (PTIR) and scattering scanning near-field optical microscopy (s-SNOM),are utilized in order to identify nanoscale properties and their influence on the functionality of halide-perovskite solar cells and catalytic nanoparticles.In the last part of this review we will address the technical challenges and opportunities in expanding the scope of IR nanospectroscopy measurements into the field of electrochemistry-based functional materials.展开更多
基金supported by the National Research Foundation of Korea through WCU(R31-2009-000-10083-0)
文摘The effect of external constraints on Li diffusion in high-capacity Li-ion battery electrodes is investigated using a coupled finite deformation theory. It is found that thinfilm electrodes on rigid substrates experience much slower diffusion rates compared with free-standing films with the same material properties and geometric dimensions. More importantly, the study reveals that mechanical driving forces tend to retard diffusion in highly-constrained thin films when lithiation-induced softening is considered, in contrast to the fact that mechanical driving forces always enhance diffusion when deformation is fully elastic. The results provide further proof that nano-particles are a better design option for nextgeneration alloy-based electrodes compared with thin films.
基金Project supported by the National Key Project of Fundamental Research of China (Grant No.2012CB932304)the National Natural Science Foundation of China (Grant No.50831006)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Ferromagnetic Ni-Mn-Ga films were fabricated by depositing on MgO （001） substrates at temperatures from 673 K to 923 K. Microstructure, crystal structure, martensitic transformation behavior, and magnetic properties of the films were studied. With increasing deposition temperature, the surface morphology of the films transforms from granular to continu- ous. The martensitic transformation temperature is not dependent on deposition temperature; while transformation behavior is affected substantially by deposition temperature. X-ray analysis reveals that the film deposited at 873 K has a 7M marten- site phase, and its magnetization curve provides a typical step-increase, indicating the occurrence of magnetically induced reorientation （MIR）. In situ magnetic domain structure observation on the film deposited at 873 K reflects that the marten- sitic transformation could be divided into two periods： nucleation and growth, in the form of stripe domains. The MIR occurs at the temperature at which martensitic transformation starts, and the switching field increases with the decrease of temperature due to damped thermal activation. The magnetically induced martensitic transformation is related to the difference of magnetization between martensite and austenite. A shift of martensite temperature of dT/dH = 0.43 K/T is observed, consistent with the theoretical value, 0.41 K/T.
文摘<strong>Objective</strong><span><span><span style="font-family:""><span style="font-family:Verdana;"><strong>:</strong> To compare the effectiveness, safety and client acceptability of concurrent application of transcervical Foley catheter with vaginal ISMN-sustained release (SR) 60 mg tablet versus transcervical Foley catheter alone for pre-induction cervical ripening in women who are undergoing Vaginal birth after C-section (VBAC). </span><b><span style="font-family:Verdana;">Method: </span></b><span style="font-family:Verdana;">A prospective single blind randomized control study w</span></span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">as carried out including 110 pregnant women who had unfavorable cervix (MBS less than 6) at 40 weeks and 3 days of gestation. The two groups received either the trans-cervical foley catheter with a vaginal ISMN 60 mg sustained release (SR) tablet on 40 weeks and 3 days (Treatment arm 1, n = 57), or trans-cervical Foley alone on 40 weeks and 3 days (Treatment arm 2, n = 53). </span><b><span style="font-family:Verdana;">Results</span></b><span style="font-family:Verdana;">: At 40 weeks + 3 days gestation</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">, </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">the mean age, mean parity and the mean modified Bishop Score (MBS) were comparable among the two treatment groups. Majority (n = 98, 89.1%) remained without spontaneously establishing labour at 24 hours of intervention. The difference in mean MBS at 40 weeks + 4 days (24-hours following the intervention) in the two groups was statistically not significant (P > 0.05). The group who received concurrent ISMN vaginal tablets achieved a higher number of successful VBACs (n = 33, 62.3%) over the group who received the Foley catheter only method (n = 29, 50.9%)</span></span></span><span
基金The present work was supported by the National Science Foundation of China.
文摘The dislocation structure of specimens of a duplex stainless steel with precharged hydrogen has been investigated by transmission electron microscopy.The result showed the hydrogen acti- vated dislocation source on phase boundaries of ferrite/austenite and makes certain dislocations in austenite grains move.The dislocation appearances in each phase in specimens uncharged with hydrogen have been given for comparison.
基金the National Natural Science Fvmdation of China (Grant No. 69872039).
文摘This paper focuses on data processing for incomplete measurement of trajectory (IMT) in aerospace measurement and control. The IMT means that the principal equipment loses the measured data during some intervals so that trajectory parameters (position, velocity, etc.) cannot be determined independently. Based on a joint model for trajectory estimation with reduced parameter, a fusion way is put forth by making full use of measured data from auxiliary equipment with lower precision. In the superposition intervals of measurement between principal and auxiliary equipment, the technique of diagnosing and estimating system errors is applied to improving the estimate precision of trajectory parameters (TP) and determining the precision after data fusion. In practical test, this method operates so successfully that it can not only provide complete TP but improve their precision remarkably. Meanwhile, this way is also applicable to other problems of incomplete measurement.
文摘Laser-in duced breakdown spectroscopy(LIBS),firstly proposed in 1962 as Brech and Cross[I]successfully detected the plasma emission induced by a ruby laser,has attracted more and more attention in both academia and industry due to its unique analytical features such as little or no sample preparation,simultaneous multi-elemental analysis,and remote sensing etc[2-4].Restrained from the highcost and poor reliability of instruments back then,the research popularity of LIBS declined quickly after a few years of initial mania of LIBS study.Since the 1990s,benefiting from the significant development of the hardware setups including laser,spectrometer,and ICCD,the'LIBS fever,re-emerged with continuous progress achieved in various applications as well as fundamental studies for the past two decades.In 2004,James D Winefordner,a prestigious an alytical scientist,crowned LIBS as a'future superstar5 for chemical analysis[5],marking the great potential of LIBS.However,on the way of fully commercialization and industrialization,LIBS is facing three big challenges:(1)to improve the quantitative analysis performance,particularly the repeatability and reproducibility performance;(2)to reduce the instrumental cost;(3)to improve the long-term stability and robustness for industrial applications.To finally transform LIBS from'future superstar,to'superstar5,joint effort of worldwide LIBS community is needed[6].
文摘The performance of functional materials and specifically energy-related functional materials,such as fuel cells,solar cells,batteries and catalysts depends on the their local,nanoscale properties.However,heterogeneities in the phase,structure and composition of these functional materials makes it difficult to directly monitor and identify the influence of local physicochemical parameters on their global functionality.In this review we will discuss recent developments in the field of IR nanospectroscopy that enables the extraction of detailed chemical information at the nanoscale and the identification of nanoscale properties that influence the global performances of functional materials.Specifically,we will discuss the ways by which infrared (IR) nanospectroscopy techniques,namely photo thermal induced resonance (PTIR) and scattering scanning near-field optical microscopy (s-SNOM),are utilized in order to identify nanoscale properties and their influence on the functionality of halide-perovskite solar cells and catalytic nanoparticles.In the last part of this review we will address the technical challenges and opportunities in expanding the scope of IR nanospectroscopy measurements into the field of electrochemistry-based functional materials.
