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Application of Electrical Capacitance Tomography to the Concentration Measurement in a Cyclone Dipleg 被引量:5
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作者 孙猛 刘石 +1 位作者 李志宏 雷兢 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第4期635-639,共5页
Accurate solid concentration measurement plays a key role in the process industry. Measurements analyzed offline can be used to estimate process efficiencies, to identify problems in a flow, and to validate computatio... Accurate solid concentration measurement plays a key role in the process industry. Measurements analyzed offline can be used to estimate process efficiencies, to identify problems in a flow, and to validate computational models. Online measurements can be used for active control. Electrical capacitance tomography (ECT) is a unique measuring technique with great potential in multiphase flow measurement. Experimental studies are carried out on a solid concentration measurement in a cyclone separator dipleg, using ECT. In this experiment eight electrodes are selected for the ECT sensor that is placed on the straight tube of the dipleg. The fluctuating characteristics according to the screw feeder and the effect of the airflow rate from the top of the cyclone are analyzed. The feasibility andreliability of the method are verified by the experimental results. 展开更多
关键词 electrical capacitance tomography concentration measurement cyclone separator dipleg gas-solid two-phase flow
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Atmospheric NO_2 Concentration Measurements Using Differential Absorption Lidar Technique
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作者 P.C.S.Devara P.Ernest Raj 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第1期73-82,共10页
Using the Differential Absorption Lidar (DIAL) technique, two types of approaches, namely, reflection from retroreflector / topographic target and backscatter from atmosphere, are available for studying remotely the a... Using the Differential Absorption Lidar (DIAL) technique, two types of approaches, namely, reflection from retroreflector / topographic target and backscatter from atmosphere, are available for studying remotely the atmospheric NO, concentration. The Argon ion lidar system at the Indian Institute of Tropical Meteorology (IITM), Pune, India has been used for the measurements by following both the path-averaged and range-resolved approaches. For the former, a topographic target (hill) is used for determining path-averaged surface concentration. In the latter, spectral properties of atmospheric attenuation is used for making range-resolved measurements in the surface layer. The results of the observations collected by following both approaches are presented. The average surface NO2 concentration was found to vary between 0.01 and 0.105 ppm and the range-resolved measurements exhibited higher values suggesting treatment of the lidar data for scattering and extinction effects due to atmospheric aerosols and air molecules, and atmospheric turbulence. Certain modifications that are suggested to the experimental set-up, data acquisition and analysis to improve the measurements are briefly described. 展开更多
关键词 Atmospheric NO2 Concentration measurements Using Differential Absorption Lidar Technique NO
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Application of Tunable Diode Laser Absorption Spectroscopy with Optical Hollow Fiber to Engine Exhaust Gas Measurement
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作者 Akira Adachi Yoshihiro Deguchi Shinichirou Konishi 《Journal of Mechanics Engineering and Automation》 2012年第11期656-662,共7页
In recent years, tighter regulation has been already enforced on harmful substances such as NOx, CO, and particles. Considering the above situation, it is important to monitor controlling factors of engine systems in ... In recent years, tighter regulation has been already enforced on harmful substances such as NOx, CO, and particles. Considering the above situation, it is important to monitor controlling factors of engine systems in order to improve efficiencies of their operations. As to car engines, an increasing concern in environmental issues such as air pollution, global warming and petroleum depletion has helped drive researches into various ways. Laser diagnostics has been applied to measure species concentration in the actual industrial fields. However there are several challenges to proceed in applying laser diagnostics to practical application. Especially stability of the measurement system is one of the most difficult issues. The purpose of this research is the development of a prompt measurement technique which can be applicable to various engine conditions. The Tunable Diode Laser Absorption Spectroscopy (TDLAS) using the hollow fiber has been developed to satisfy above requirements. By using a hollow fiber, misalignment of an optical axis and vulnerability of measurement environment such as vibration can be greatly reduced with sensitive and fast response features. It was demonstrated that this method can be applicable to measure gas compositions in engine exhaust with a range of millisecond response time. A sensitive method using tunable UV diode laser absorption spectroscopy was also discussed to detect NOx in exhausts. 展开更多
关键词 Tunable diode laser absorption spectroscopy optical hollow fiber exhaust gas concentration measurement.
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Effect of Vortex Stirring on the Dilution of Copper Slag 被引量:1
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作者 ZHANG Baojing ZHANG Tingan +1 位作者 DOU Zhihe ZHANG Dongliang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第4期699-706,共8页
In order to solve the problem that the vulcanizing agent utilization rate is low and the dilution effect of copper slag is poor,the vortex stirring dilution method was used to improve the conditions of the dilution ki... In order to solve the problem that the vulcanizing agent utilization rate is low and the dilution effect of copper slag is poor,the vortex stirring dilution method was used to improve the conditions of the dilution kinetics and copper recovery.The water model was used to simulate the effect of copper slag dilution.Under the premise of keeping the Reynolds number consistent,silicone oil and glass beads were used instead of copper slag and vulcanizing agent.Based on the relationship between voltage and concentration,the PC6D dual-channel particle concentration measuring instrument was used to study the stirring speed and the insertion depth of the stirring paddle in model experiments,and the suitable conditions were speed 250 rpm and insertion depth 70 mm.The fire dilution of copper slag was done under the conditions.After stirring and sedimentation,the Fe_(3)O_(4) in slag decreased from 22.58% to 4.65%,and the copper content of the slag decreased from 2.94% to 0.34%.The copper recovery was 88.44%. 展开更多
关键词 copper slag dilution vortex stirring water model the PC6D dual-channel particle concentration measuring instrument
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A handy method for estimating the particle concentration distribution in FCC risers using a gamma-ray transmission technique
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作者 Liu Xiaocheng Wei Yaodong Song Jianfei 《Petroleum Science》 SCIE CAS CSCD 2014年第2期318-322,共5页
A handy gamma-ray transmission method for estimating the particle concentration distribution in a fluid catalytic cracking (FCC) riser is proposed. The method is based on an empirical correlation ε(r)= ε-(0.19... A handy gamma-ray transmission method for estimating the particle concentration distribution in a fluid catalytic cracking (FCC) riser is proposed. The method is based on an empirical correlation ε(r)= ε-(0.191+φ25+3φ11), which has only one unknown parameter y, hence only one single-beam experimental result is enough to estimate the particle concentration distribution in the riser. In order to verify the feasibility of this method, the particle concentrations of three cross-sections of the laboratory riser were measured and the distribution profiles were compared with those reported in the literature. Furthermore, by comparing other gamma-ray function methods applied in the measurement of risers, this method has distinct advantages, such as the device is simple and has no moving parts, the measurement is rapid, and the safety is high because only one gamma-ray beam is used. Therefore, the method has promising applications in estimating particle concentrations or monitoring operation conditions of risers. 展开更多
关键词 GAMMA-RAY RISER FCC catalyst concentration measurement
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Polypyrrole Chitosan Cobalt Ferrite Nanoparticles Composite Layer for Measuring the Low Concentration of Fluorene Using Surface Plasmon Resonance
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作者 A.R.Sadrolhosseini M.Naseri M.K.Halimah 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第5期111-114,共4页
Fluorene is a polycyclic aromatic hydrocarbon, which is a hazardous toxic chemical in the environment. The measurement of low concentrations of fluorene is a subject of intense interest in chemistry and in the environ... Fluorene is a polycyclic aromatic hydrocarbon, which is a hazardous toxic chemical in the environment. The measurement of low concentrations of fluorene is a subject of intense interest in chemistry and in the environment. Polypyrrole chitosan cobalt ferrite nanoparticles are prepared using the electrochemical method. The prepared layers are characterized using field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and energy dispersive spectroscopy. The layers are used to detect fluorene using the surface plasmon resonance technique at room temperature. The composite layer is evaluated after detection of fluorene using atomic force microscopy. The fluorene is bound on the layer, and the shift of the resonance angle is about 0.0052°, corresponding to the limitation of 0.01 ppm. 展开更多
关键词 Co NP Polypyrrole Chitosan Cobalt Ferrite Nanoparticles Composite Layer for Measuring the Low Concentration of Fluorene Using Surface Plasmon Resonance
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From E=mc^(2) to E=mc^(2)/22—A Short Account of the Most Famous Equation in Physics and Its Hidden Quantum Entanglement Origin
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作者 Mohamed S.El Naschie 《Journal of Quantum Information Science》 2014年第4期284-291,共8页
Einstein’s energy mass formula is shown to consist of two basically quantum components E(O) = mc2/22 and E(D) = mc2(21/22). We give various arguments and derivations to expose the quantum entanglement physics residin... Einstein’s energy mass formula is shown to consist of two basically quantum components E(O) = mc2/22 and E(D) = mc2(21/22). We give various arguments and derivations to expose the quantum entanglement physics residing inside a deceptively simple expression E = mc2. The true surprising aspect of the present work is however the realization that all the involved “physics” in deriving the new quantum dissection of Einstein’s famous formula of special relativity is actually a pure mathematical necessity anchored in the phenomena of volume concentration of convex manifold in high dimensional quasi Banach spaces. Only an endophysical experiment encompassing the entire universe such as COBE, WMAP, Planck and supernova analysis could have discovered dark energy and our present dissection of Einstein’s marvelous formula. 展开更多
关键词 Special Relativity Varying Speed of Light Hardy’s Quantum Entanglement Dark Energy Measure Concentration in Banach Space ‘tHooft Fractal Spacetime Witten Fractal M-Theory E-Infinity Theory Transfinite Cellular Automata Golden Mean Computer Endophysics Finkelstein-Rossler-Primas Theory of Interface
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Ultrasonic concentration measurement of citrus pectin aqueous solutions using PC and PLS regression 被引量:2
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作者 Meng Ruifeng Zhong Jianjun +2 位作者 Zhang Lifen Ye Xingqian Liu Donghong 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2012年第2期76-81,共6页
This work demonstrated the use of multivariate statistical techniques called principal component(PC)and partial least squares(PLS)to extract the acoustic features of citrus pectin water solution.The concentration of c... This work demonstrated the use of multivariate statistical techniques called principal component(PC)and partial least squares(PLS)to extract the acoustic features of citrus pectin water solution.The concentration of citrus pectin water solution was predicted by PC and PLS regression method using the spectra of ultrasound pulse echoes travelling through mixtures.The values of root mean square error of validation(RMSEV)were 0.0675 g/100 g and 0.0662 g/100 g for PC and PLS regression model,respectively.Since the response variable was taken into account,PLS regression model was more accurate than PC regression model.Also,a method for temperature compensation was proposed to correct the impact of temperature variation on analyzed data.The proposed methods for pectin concentration measurement are easily adaptable to similar applications using existing hardware. 展开更多
关键词 Partial Least Square Regression Principal Component Regression concentration measurement acoustic velocity
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Application of transcutaneous diffuse reflectance spectroscopy in the measurement of blood glucose concentration 被引量:5
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作者 陈文亮 刘蓉 +2 位作者 崔厚欣 徐可欣 吕丽娜 《Chinese Optics Letters》 SCIE EI CAS CSCD 2004年第7期411-413,共3页
In this paper, the propagation characteristics of near-infrared (NIR) light in the palm tissue are analyzed, and the principle and feasibility of using transcutaneous diffuse reflectance spectroscopy for non-invasive ... In this paper, the propagation characteristics of near-infrared (NIR) light in the palm tissue are analyzed, and the principle and feasibility of using transcutaneous diffuse reflectance spectroscopy for non-invasive blood glucose detection are presented. An optical probe suitable for measuring the diffuse reflectance spectrum of human palm and a non-invasive blood glucose detection system using NIR spectroscopy are designed. Based on this system, oral glucose tolerance tests are performed to measure the blood glucose concentrations of two young healthy volunteers. The partial least square calibration model is then constructed by all individual experimental data. The final result shows that correlation coefficients of the two experiments between the predicted blood glucose concentrations and the reference blood glucose concentrations are 0.9870 and 0.9854, respectively. The root mean square errors of prediction of full cross validation are 0.54 and 0.52 mmol/1, respectively. 展开更多
关键词 Application of transcutaneous diffuse reflectance spectroscopy in the measurement of blood glucose concentration NIR OGTT
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Experimental measurements of gas-solid flow and splitting mechanisms of a coal pipe splitter with a perpendicularly arranged upstream elbow
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作者 Hao Zhou Yan Huang +3 位作者 Yu Yang Guiyuan Mo Jianzhong Li Kefa Cen 《Particuology》 SCIE EI CAS CSCD 2016年第2期143-150,共8页
The effect of the vertical pipe length on the performance of a coal pipe splitter with a perpendicularly arranged upstream elbow was investigated experimentally employing a fiber optic measuring system. The upstream e... The effect of the vertical pipe length on the performance of a coal pipe splitter with a perpendicularly arranged upstream elbow was investigated experimentally employing a fiber optic measuring system. The upstream elbow and coal pipe splitter were installed in two perpendicular planes. Contours of dis- tributions of the particle concentration and size were obtained in different transverse sections. The experimental data show that the maximum/minimum concentration ratio in transverse sections A, B, and C decreased rapidly as the length of the vertical pipe increased. The left/right-leg average concentration ratio remained about 1, and a balanced split was thus achieved. With a perpendicularly arranged upstream elbow, the vertical pipe length had little effect on the splitter performance, which is beneficial for engineering design and convenient for industrial application. 展开更多
关键词 Gas-solid flow Concentration measurement Coal pipe splitter Fiber optic sensor
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Weak Poincaré Inequalities,Decay of Markov Semigroups and Concentration of Measures 被引量:3
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作者 Feng Yu WANG Qi Zhi ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第4期937-942,共6页
For a reasonable class of weak Poincaré inequalities, the decay of the corresponding Markov semigroups obtained earlier by Rockner and the first named author is improved by removing an extra L^2-norm. Next, a con... For a reasonable class of weak Poincaré inequalities, the decay of the corresponding Markov semigroups obtained earlier by Rockner and the first named author is improved by removing an extra L^2-norm. Next, a concentration estimate of the reference measure is presented for the weak Poincaré inequality, which is sharp as illustrated by some examples of one-dimensional diffusion processes. 展开更多
关键词 Weak Poincaré inequality Markov semigroup Concentration of measures
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Optimizing photosynthetic and respiratory parameters based on the seasonal variation pattern in regional net ecosystem productivity obtained from atmospheric inversion 被引量:1
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作者 Zhuoqi Chen Jing M.Chen +6 位作者 Xiaogu Zheng Fei Jiang Jun Qin Shupeng Zhang Wenping Yuan Weiming Ju Gang Mo 《Science Bulletin》 SCIE EI CAS CSCD 2015年第22期1954-1961,共8页
In this study, we explore the feasibility of optimizing ecosystem photosynthetic and respiratory parameters from the seasonal variation of the net carbon flux. An optimization scheme is proposed to estimate two key pa... In this study, we explore the feasibility of optimizing ecosystem photosynthetic and respiratory parameters from the seasonal variation of the net carbon flux. An optimization scheme is proposed to estimate two key parameters (V2max and Q10) by exploiting the seasonal variation in the net ecosystem carbon flux retrieved by an atmospheric inversion system. This scheme is implemented to estimate V25max and Q10 of the boreal ecosystem productivity simulator (BEPS) to improve its NEP simulation in the boreal North American region. Then, in situ NEE observations at six eddy covariance sites are used to evaluate the NEE simulations from BEPS with initial and optimized parameters. The results show that the performance of the optimized BEPS is superior to that of the BEPS with the default parameter values. These results implicate that it is possible to optimize ecosystem model parameters by different sensitivities of V25max and Q10 during growing and non-growing seasons through atmospheric inversion or data assimilation techniques. 展开更多
关键词 Parameter optimization Land surfacemodel CO2 concentration measurements - NEP
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Landmarks in the application of electrical tomography in particle science and technology 被引量:4
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作者 Richard A.Williams 《Particuology》 SCIE EI CAS CSCD 2010年第6期493-497,共5页
Selected milestones in the development and use of electrical tomography in powder conveying, slurry processing and multi-phase flow are highlighted. The ability to map concentration in opaque mixtures under process-re... Selected milestones in the development and use of electrical tomography in powder conveying, slurry processing and multi-phase flow are highlighted. The ability to map concentration in opaque mixtures under process-realistic conditions was a major innovation for the method and has had far reaching implications. Subsequent developments have enabled velocity information to be abstracted resulting in the ability to measure component flux and motion. 展开更多
关键词 Computational fluid dynamics Fault condition and maloperation Flow measurement Flow regime identification Particle concentration Process control Process safety
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Transportation inequalities for hidden Markov chains and applications
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作者 HU ShuLan 《Science China Mathematics》 SCIE 2011年第5期1027-1042,共16页
We prove some transportation inequalities for hidden Markov chains, generalize the results proved by Kontorovich and Ramanan in two directions and give some applications to log-likelihood functions and hypothesis test... We prove some transportation inequalities for hidden Markov chains, generalize the results proved by Kontorovich and Ramanan in two directions and give some applications to log-likelihood functions and hypothesis testing. 展开更多
关键词 hidden Markov chains deviation inequalities transportation cost-information inequality measure concentration exponential forgetting geometric ergodicity
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Indoor and outdoor particle concentration distributions of a typical meeting room during haze and clear-sky days
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作者 LI YanLong JIN XinMing +2 位作者 YANG LiJun DU XiaoZe YANG YongPing 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第3期355-362,共8页
Air quality has increasingly been a great concern all over the world,and the good command of indoor and outdoor air qualities is of
关键词 indoor and outdoor environment particle concentration mass concentration PM2.5 in-situ measurement
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