Sulfate-modified titanium dioxide-bearing blast furnace slag（STBBFS） photocatalysts were prepared by the high energy ball milling method with（NH4）2SO4 and titanium dioxide-bearing blast furnace slag（TBBFS） as ra...Sulfate-modified titanium dioxide-bearing blast furnace slag（STBBFS） photocatalysts were prepared by the high energy ball milling method with（NH4）2SO4 and titanium dioxide-bearing blast furnace slag（TBBFS） as raw materials.X-ray photoelectron spectroscopy（XPS）,X-ray diffraction（XRD）,scanning electron microscopy（SEM）,thermogravimetric analysis（TGA）,UV-visible diffuse reflectance absorption spectra（UV-Vis）,adsorption experiment and photocatalytic degradation measurement were conducted to characterize the structure,surface status,light absorption capacity,adsorption capacity and photocatalytic activity of the obtained photocatalysts.The adsorption equilibrium was described by the Langmuir isotherm model with a maximum adsorption capacity of 8.25 mg/g of Cr（VI） ions onto the STBBFS photocatalysts.As a result,sulfation of TBBFS improved the photocatalytic activities of STBBFSx photocatalysts.At a low calcination temperature,the photocatalytic activity of STBBFS300 photocatalyst was markedly higher compared with TBBFSx prepared at high calcination temperature,indicating that the photocatalytic activity of STBBFSx photocatalyst was determined by the balanced result between adsorption capacity and perovskite content.展开更多
The experimental study on negative capacitance（NO） of various light-emitting diodes（LEDs） is presented. Experimental result shows that all LEDs display the NO phenomenon. The voltage modulated electroluminescence...The experimental study on negative capacitance（NO） of various light-emitting diodes（LEDs） is presented. Experimental result shows that all LEDs display the NO phenomenon. The voltage modulated electroluminescence（VMEL） experiment confirms that the reason of negative capacitance is the strong recombination of the injected carriers in the active region of luminescence. The measures also verify that the dependence of NO on voltage and frequency in different LEDs is similar. NO phenomenon is more obvious with higher voltage or lower frequency.展开更多
Photoplethysmogram(PPG)is a noninvasive method for detecting human cardiovascular pulse wave using optical technology.The PPG containing a lot of physiological information is from the MIMIC database.This paper propose...Photoplethysmogram(PPG)is a noninvasive method for detecting human cardiovascular pulse wave using optical technology.The PPG containing a lot of physiological information is from the MIMIC database.This paper proposes a combinatorial method of ensemble empirical mode decomposition(EEMD),cepstrum,fast Fourier transform(FFT)and zero-crossing detection to improve the robustness of the estimation of pulse rate(PR),heart rate(HR)and respiratory rate(RR)from the PPG.First,the PPG signal was decomposed into finite intrinsic mode functions(IMF)by EEMD.Because of its adaptive filtering property,the different signals were reconstructed using different IMFs when estimating different physiological parameters.Second,the PR was obtained by zero-crossing detection after rejecting low frequency IMFs containing artifacts.Third,IMFs with frequency between 1.00 Hz to 1.67 Hz(60 beats/min to 100 beats/min)were selected for estimating HR.Then,the frequency band that reflects the heart activity was analyzed by the cepstrum method.Finally,the respiratory signal can be extracted from PPG signal by IMFs with frequency between 0.05 Hz to 0.75 Hz(3 breahts/min to 45 breaths/min).Then the spectrum of signal was obtained by FFT analysis and the RR was estimated by detecting the maximum frequency peak.The algorithm has been tested on MIMIC database obtained from 53 adults.The experiment results show that the physiological parameters extracted by this integrated signal processing method are consistent with the real physiological parameters.And the computation load of this method is small and the precision is high(not larger than 1.17%in error).展开更多
The influence of tungsten trioxide(WO3)loading on the selective catalytic reduction(SCR)of nitric oxide(NO)by ammonia(NH3)over WO3/cerium dioxide(CeO2)was investigated.The NO conversion first rose and then declined wi...The influence of tungsten trioxide(WO3)loading on the selective catalytic reduction(SCR)of nitric oxide(NO)by ammonia(NH3)over WO3/cerium dioxide(CeO2)was investigated.The NO conversion first rose and then declined with increasing WO3loading.It was found that the crystalline WO3in the1.6WO3/CeO2sample could be removed in25wt%ammonium hydroxide at70°C,which improved the catalytic activity of the sample.The obtained samples were characterized by X‐ray diffraction,Raman spectroscopy,X‐ray photoelectron spectroscopy,hydrogen(H2)temperature programmed reduction,NH3temperature programmed desorption,and in situ diffuse reflectance infrared Fourier transform spectroscopy.The results revealed that the dispersed WO3promoted the catalytic activity of WO3/CeO2while the crystalline WO3inhibited catalytic activity.The oxygen activation of CeO2was inhibited by the coverage of WO3,which weakened NO oxidation and adsorption of nitrate species over WO3/CeO2.In addition,the NH3adsorption performance on CeO2was improved by modification with WO3.NH3was the most stable adsorbed species under NH3SCR reaction conditions.In situ DRIFT spectra suggested that the NH3SCR reaction proceeded via the Eley‐Rideal mechanism over WO3/CeO2.Thus,when the loading of WO3was close to the dispersion capacity,the effects of NH3adsorption and activation were maximized to promote the reaction via the Eley‐Rideal route.展开更多
A method of improving the accuracy of laser pulse range finding from ±10 m to ±1 m inexpensively by means of time scale up is described. Time scale up can stretch the entire flight time by a factor of 1 00...A method of improving the accuracy of laser pulse range finding from ±10 m to ±1 m inexpensively by means of time scale up is described. Time scale up can stretch the entire flight time by a factor of 1 000 and then the stretched result is counted to calculate the distance. The use of this technique decreases the resolution of counting from nanosecond to microsecond, therefore a separate counting oscillator followed by an interpolation operation is unnecessary. This technique can improve the accuracy of laser pulse range finding inexpensively and effectively.展开更多
The earthquake demand spectrum is often assumed as the average spectrum in the seismic design code or based upon probabilistic models to take into account the uncertainties of ground motion. The average spectrum can n...The earthquake demand spectrum is often assumed as the average spectrum in the seismic design code or based upon probabilistic models to take into account the uncertainties of ground motion. The average spectrum can not deal with the uncertainty of earthquake excitation. Furthermore, results of probabilistic analysis are suspicious when information describing the uncertainty is inadequate. Considering the uncertainties of peak acceleration of ground motion and characteristic period of response spectra using a double bounded convex set model, the bounds of the design spectrum and the demand spectrum were obtained based on Chinese seismic code. Then the convex analysis method was integrated into the capacity spectrum procedure to study the bound characteristics of target displacement. Finally, the target displacement was derived with an interval, and it is more objective and robust with respect to probabilistic perspective.展开更多
The PN junction photodiode is fabricated with high resistivity P-type silicon ( ρ =12 000 Ω·cm).The experimental C-V curves with and without laser radiation were measured.The relative change of capacitanc...The PN junction photodiode is fabricated with high resistivity P-type silicon ( ρ =12 000 Ω·cm).The experimental C-V curves with and without laser radiation were measured.The relative change of capacitance can be greater than 100%,which is much greater than the relative change for low resistivity P-type silicon.The relative change of capacitance with and without laser radiation at zero bias is 121.7%.展开更多
A Mixed Line Rate(MLR)optical network is a good candidate for a core backbone network because of its ability to provide diverse line rates to effectively accommodate traffic demands with heterogeneous bandwidth requir...A Mixed Line Rate(MLR)optical network is a good candidate for a core backbone network because of its ability to provide diverse line rates to effectively accommodate traffic demands with heterogeneous bandwidth requirements.Because of the deleterious effects of physical impairments,there is a maximum transmission reach for optical signals before they have to be regenerated.Being expensive devices,regenerators are expected to be sparsely located and used in such a network,called a translucent optical network.In this paper,we consider the Grooming,Routing,and Wavelength Assignment(GRWA)problem so that the Quality of Transmission(QoT)for connections is satisfied,and the network-level performance metric of blocking probability is minimized.Cross-layer heuristics to effectively allocate the sparse regenerators in MLR networks are developed,and extensive simulation results are presented to demonstrate their effectiveness.展开更多
基金Project (2007CB613504) supported by the National Basic Research Program of ChinaProject (307009) supported by the Foundation for Key Program of Ministry of Education,China+1 种基金Project (N110423003) supported by the Fundamental Research Funds for the Central Universities,ChinaProject (E2012501012) supported by Natural Science Foundation-Steel and Iron Foundation of Hebei Province,China
文摘Sulfate-modified titanium dioxide-bearing blast furnace slag（STBBFS） photocatalysts were prepared by the high energy ball milling method with（NH4）2SO4 and titanium dioxide-bearing blast furnace slag（TBBFS） as raw materials.X-ray photoelectron spectroscopy（XPS）,X-ray diffraction（XRD）,scanning electron microscopy（SEM）,thermogravimetric analysis（TGA）,UV-visible diffuse reflectance absorption spectra（UV-Vis）,adsorption experiment and photocatalytic degradation measurement were conducted to characterize the structure,surface status,light absorption capacity,adsorption capacity and photocatalytic activity of the obtained photocatalysts.The adsorption equilibrium was described by the Langmuir isotherm model with a maximum adsorption capacity of 8.25 mg/g of Cr（VI） ions onto the STBBFS photocatalysts.As a result,sulfation of TBBFS improved the photocatalytic activities of STBBFSx photocatalysts.At a low calcination temperature,the photocatalytic activity of STBBFS300 photocatalyst was markedly higher compared with TBBFSx prepared at high calcination temperature,indicating that the photocatalytic activity of STBBFSx photocatalyst was determined by the balanced result between adsorption capacity and perovskite content.
基金This workis supported by the National Nature Science Founda-tion (Grant No.DMR-60376027)
文摘The experimental study on negative capacitance（NO） of various light-emitting diodes（LEDs） is presented. Experimental result shows that all LEDs display the NO phenomenon. The voltage modulated electroluminescence（VMEL） experiment confirms that the reason of negative capacitance is the strong recombination of the injected carriers in the active region of luminescence. The measures also verify that the dependence of NO on voltage and frequency in different LEDs is similar. NO phenomenon is more obvious with higher voltage or lower frequency.
文摘Photoplethysmogram(PPG)is a noninvasive method for detecting human cardiovascular pulse wave using optical technology.The PPG containing a lot of physiological information is from the MIMIC database.This paper proposes a combinatorial method of ensemble empirical mode decomposition(EEMD),cepstrum,fast Fourier transform(FFT)and zero-crossing detection to improve the robustness of the estimation of pulse rate(PR),heart rate(HR)and respiratory rate(RR)from the PPG.First,the PPG signal was decomposed into finite intrinsic mode functions(IMF)by EEMD.Because of its adaptive filtering property,the different signals were reconstructed using different IMFs when estimating different physiological parameters.Second,the PR was obtained by zero-crossing detection after rejecting low frequency IMFs containing artifacts.Third,IMFs with frequency between 1.00 Hz to 1.67 Hz(60 beats/min to 100 beats/min)were selected for estimating HR.Then,the frequency band that reflects the heart activity was analyzed by the cepstrum method.Finally,the respiratory signal can be extracted from PPG signal by IMFs with frequency between 0.05 Hz to 0.75 Hz(3 breahts/min to 45 breaths/min).Then the spectrum of signal was obtained by FFT analysis and the RR was estimated by detecting the maximum frequency peak.The algorithm has been tested on MIMIC database obtained from 53 adults.The experiment results show that the physiological parameters extracted by this integrated signal processing method are consistent with the real physiological parameters.And the computation load of this method is small and the precision is high(not larger than 1.17%in error).
基金supported by the National Natural Foundation of China(21607019,21503115)the Open Project Program of Jiangsu Key Laboratory of Vehicle Emissions Control(OVEC013)the Talent Introduction Project of Chongqing Three Gorges University~~
文摘The influence of tungsten trioxide(WO3)loading on the selective catalytic reduction(SCR)of nitric oxide(NO)by ammonia(NH3)over WO3/cerium dioxide(CeO2)was investigated.The NO conversion first rose and then declined with increasing WO3loading.It was found that the crystalline WO3in the1.6WO3/CeO2sample could be removed in25wt%ammonium hydroxide at70°C,which improved the catalytic activity of the sample.The obtained samples were characterized by X‐ray diffraction,Raman spectroscopy,X‐ray photoelectron spectroscopy,hydrogen(H2)temperature programmed reduction,NH3temperature programmed desorption,and in situ diffuse reflectance infrared Fourier transform spectroscopy.The results revealed that the dispersed WO3promoted the catalytic activity of WO3/CeO2while the crystalline WO3inhibited catalytic activity.The oxygen activation of CeO2was inhibited by the coverage of WO3,which weakened NO oxidation and adsorption of nitrate species over WO3/CeO2.In addition,the NH3adsorption performance on CeO2was improved by modification with WO3.NH3was the most stable adsorbed species under NH3SCR reaction conditions.In situ DRIFT spectra suggested that the NH3SCR reaction proceeded via the Eley‐Rideal mechanism over WO3/CeO2.Thus,when the loading of WO3was close to the dispersion capacity,the effects of NH3adsorption and activation were maximized to promote the reaction via the Eley‐Rideal route.
文摘A method of improving the accuracy of laser pulse range finding from ±10 m to ±1 m inexpensively by means of time scale up is described. Time scale up can stretch the entire flight time by a factor of 1 000 and then the stretched result is counted to calculate the distance. The use of this technique decreases the resolution of counting from nanosecond to microsecond, therefore a separate counting oscillator followed by an interpolation operation is unnecessary. This technique can improve the accuracy of laser pulse range finding inexpensively and effectively.
文摘The earthquake demand spectrum is often assumed as the average spectrum in the seismic design code or based upon probabilistic models to take into account the uncertainties of ground motion. The average spectrum can not deal with the uncertainty of earthquake excitation. Furthermore, results of probabilistic analysis are suspicious when information describing the uncertainty is inadequate. Considering the uncertainties of peak acceleration of ground motion and characteristic period of response spectra using a double bounded convex set model, the bounds of the design spectrum and the demand spectrum were obtained based on Chinese seismic code. Then the convex analysis method was integrated into the capacity spectrum procedure to study the bound characteristics of target displacement. Finally, the target displacement was derived with an interval, and it is more objective and robust with respect to probabilistic perspective.
文摘The PN junction photodiode is fabricated with high resistivity P-type silicon ( ρ =12 000 Ω·cm).The experimental C-V curves with and without laser radiation were measured.The relative change of capacitance can be greater than 100%,which is much greater than the relative change for low resistivity P-type silicon.The relative change of capacitance with and without laser radiation at zero bias is 121.7%.
基金supported in part by National Science Foundation (NSF) under Grants No. CNS-0915795 and No.CNS-0916890
文摘A Mixed Line Rate(MLR)optical network is a good candidate for a core backbone network because of its ability to provide diverse line rates to effectively accommodate traffic demands with heterogeneous bandwidth requirements.Because of the deleterious effects of physical impairments,there is a maximum transmission reach for optical signals before they have to be regenerated.Being expensive devices,regenerators are expected to be sparsely located and used in such a network,called a translucent optical network.In this paper,we consider the Grooming,Routing,and Wavelength Assignment(GRWA)problem so that the Quality of Transmission(QoT)for connections is satisfied,and the network-level performance metric of blocking probability is minimized.Cross-layer heuristics to effectively allocate the sparse regenerators in MLR networks are developed,and extensive simulation results are presented to demonstrate their effectiveness.
