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A Multi-level Approach for Complex Fault Isolation Based on Structured Residuals 被引量:4
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作者 叶鲁彬 石向荣 梁军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第3期462-472,共11页
In industrial processes,there exist faults that have complex effect on process variables.Complex and simple faults are defined according to their effect dimensions.The conventional approaches based on structured resid... In industrial processes,there exist faults that have complex effect on process variables.Complex and simple faults are defined according to their effect dimensions.The conventional approaches based on structured residuals cannot isolate complex faults.This paper presents a multi-level strategy for complex fault isolation.An extraction procedure is employed to reduce the complex faults to simple ones and assign them to several levels.On each level,faults are isolated by their different responses in the structured residuals.Each residual is obtained insensitive to one fault but more sensitive to others.The faults on different levels are verified to have different residual responses and will not be confused.An entire incidence matrix containing residual response characteristics of all faults is obtained,based on which faults can be isolated.The proposed method is applied in the Tennessee Eastman process example,and the effectiveness and advantage are demonstrated. 展开更多
关键词 MULTI-LEVEL structured residuals principal component analysis complex fault isolation Tennessee Eastman process
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CHROMATOGRAPHIC SEPERATION AND PURIFICATION OF HUMAN CHORIONIC GONADOTROPIN
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作者 Wang Haifeng Xu Yutai +2 位作者 Ren Rougli Tang Lei Wang Hairen 《Chinese Journal of Reactive Polymers》 1995年第1期39-44,共6页
Seperation and purifitation of human chorionic gonadotropion (HCG) in theurine sample of early pregnant women by D3520 resin adsorption chromatographyis repaied. The crude product obtained by DEAE - Cellulose 23 and ... Seperation and purifitation of human chorionic gonadotropion (HCG) in theurine sample of early pregnant women by D3520 resin adsorption chromatographyis repaied. The crude product obtained by DEAE - Cellulose 23 and DEAE Sephadex A50 column chromatography showed a high activity of HCG. Furtherpurifikation of the sample by gel filtration chromatography on a Sephadex G75 column gives a final preparation of 6000~ 6500 IU/mg. The preparation meets therequiTements of the pyrogn test in Chinese Law of Pharmacopoeia. 展开更多
关键词 CHROMATOGRAPHY human chorionic gonadotorpion D3520 resin
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Entanglement and Phase-Covariant Cloning for Multiple Trapped Ions via Adiabatic Passage
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作者 LU Dao-Ming ZHENG Shi-Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期649-651,共3页
We describe a scheme for the generation of W states and implementation of phase-covariant cloning for n trapped ions. The scheme does not use the vibational mode as the memory and works beyond the Lamb-Dicke regime. T... We describe a scheme for the generation of W states and implementation of phase-covariant cloning for n trapped ions. The scheme does not use the vibational mode as the memory and works beyond the Lamb-Dicke regime. The procedure is robust against moderate fluctuations of experimental parameters by using adiabatic passage. 展开更多
关键词 ENTANGLEMENT trapped ion adiabatic passage
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Mathematical modeling of salt-gradient ion-exchange simulated moving bed chromatography for protein separations 被引量:1
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作者 卢建刚 《Journal of Zhejiang University Science》 EI CSCD 2004年第12期1613-1620,共8页
The salt-gradient operation mode used in ion-exchange simulated moving bed chromatography (SMBC) can improve the efficiency of protein separations. A detailed model that takes into account any kind of adsorption/ion-e... The salt-gradient operation mode used in ion-exchange simulated moving bed chromatography (SMBC) can improve the efficiency of protein separations. A detailed model that takes into account any kind of adsorption/ion-exchange equilibrium, salt gradient, size exclusion, mass transfer resistance, and port periodic switching mechanism, was developed to simulate the complex dynamics. The model predictions were verified by the experimental data on upward and downward gradients for protein separations reported in the literature. All design and operating parameters (number, configuration, length and diameter of columns, particle size, switching period, flow rates of feed, raffinate, desorbent and extract, protein concentrations in feed, different salt concentrations in desorbent and feed) can be chosen correctly by numerical simulation. This model can facilitate the design, operation, optimization, control and scale-up of salt-gradient ion-exchange SMBC for protein separations. 展开更多
关键词 Simulated moving bed chromatography Salt gradients Size exclusion PROTEINS Mathematical model
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Optimization of Isolation and Identification Conditions of Glibenclamide Annotation
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作者 Ordabayeva Saule Kutymovna Karakulova Aizhan Shirinbekovna +1 位作者 Serikbayeva Aigul Djumadullayevna Mirsoatova Mokhinur 《Journal of Pharmacy and Pharmacology》 2016年第8期398-404,共7页
A method for dispersive liquid-liquid microextraction of glibenclamide on model mixtures with urine has been developed. The extraction conditions have been optimized and the influence of extractants and dispersing age... A method for dispersive liquid-liquid microextraction of glibenclamide on model mixtures with urine has been developed. The extraction conditions have been optimized and the influence of extractants and dispersing agent for allocation of toxicant from biosubstrate has been experimentally established. The method of TLC (thin layer chromatography) screening in order to remove endogenous and exogenous substances has been developed. The method of IR-spectroscopy for confirmatory analysis has been used. The combination of the two methods of analysis allows identifying glibenclamide quickly and reliably isolated from bioliquid and reducing the risk of false-positive results. 展开更多
关键词 GLIBENCLAMIDE dispersive liquid-liquid extraction biological liquid thin layer chromatography and infrared spectroscopy.
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STUDY ON DETERMINATION OF TRACE Fe BY Fe(Ⅱ)-VA THIN LAYER RESIN PHASE SPECTROPHOTOMETRY
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作者 SONG Huanyu YAN Yongsheng WANG Yun 《Chinese Journal of Reactive Polymers》 2006年第2期155-160,共6页
A new method for the determination of Fe by thin layer resin phase spectrophotometry in alkali condition was reported. The complex anion formed by Fe(Ⅱ) and VA was absorbed on the 717w resin and Fe was determined b... A new method for the determination of Fe by thin layer resin phase spectrophotometry in alkali condition was reported. The complex anion formed by Fe(Ⅱ) and VA was absorbed on the 717w resin and Fe was determined by making thin layer. This method had a high sensitivity (ε620= 3.0×10^5L/mol.cm), which was 15 times higher than that of liquid phase spectrophotometry. It had been proved a satisfactory precision (5.01μg Fe, n=6, RSD=1.8%). The trace Fe in natural water was determined and the recovery was 97%. 展开更多
关键词 Thin layer resin phase spectrophotometry TRACE FE
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Characterization of CulnS2 Thin Films with Different Cu/In Ratio
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作者 Mutlu Kundakcl 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期582-586,622,共6页
Thin films of CuInS2 were grown on glass reaction method with different [Cu]/[In] substrate by successive ionic layer adsorption and ratios and annealed at 400℃ for 30 rain. The crystal structure and grain sizes of t... Thin films of CuInS2 were grown on glass reaction method with different [Cu]/[In] substrate by successive ionic layer adsorption and ratios and annealed at 400℃ for 30 rain. The crystal structure and grain sizes of the thin films were characterized by X-ray diffraction method. Atomic force microscopy was used to determine surface morphology of the films. Optical and electrical properties of these films were investigated as a function of [Cu]/[In] ratios. The electrical resistivity of CuInS~ of thin films was determined using a direct current- two probe method in the temperature range of 300-470 K. It is observed that, the electrical resistivity values show a big decreasing with increasing [Cu]/[In] ratio. Hence, the [Cu]/[In] ratio in the solution can drastically affect the structural, electrical, and optical properties of thin films of CuInS2. 展开更多
关键词 Thin filml Successive ionic layer adsorption Chalcopyrite compound
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Research on Ground Movement Laws for Strip Mining Under Thick Alluvium
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作者 谭志祥 邓喀中 杨军 《Journal of China University of Mining and Technology》 2002年第1期61-64,共4页
With the discrete element method, the simulation and analysis of a series of numerical models were made. This research revealed ground movement laws for strip mining under thick alluvium and gave calculation formulae ... With the discrete element method, the simulation and analysis of a series of numerical models were made. This research revealed ground movement laws for strip mining under thick alluvium and gave calculation formulae for the maximum ground subsidence and horizontal movement as a function of basement rock thickness and mining width, thus providing sound evidence for future strip mining under thick alluvium. 展开更多
关键词 thick alluvium strip mining movement and deformation discrete element method
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Advances in numerical simulation of demolition blasting
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作者 Xie Xianqi Liu Jun +1 位作者 Jia Yongsheng Sun Jinshan 《Engineering Sciences》 EI 2014年第6期24-31,共8页
The applications of numerical simulation in demolition blasting were reviewed.Several methods of numerical simulation in demolition blasting were introduced.The strength and weakness of the numerical methods mentioned... The applications of numerical simulation in demolition blasting were reviewed.Several methods of numerical simulation in demolition blasting were introduced.The strength and weakness of the numerical methods mentioned in this paper were also indicated,respectively.Furthermore,the solid lattice model in the frame of discrete element method(DEM),which was developed by the author and his team,was detailedly described.The existed problems in the current numerical simulation methods of demolition blasting were presented and the future trend of the numerical simulation is finally prospected. 展开更多
关键词 demolition blasting numerical simulation discrete element method solid lattice model
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Detection of methane plumes in the water column of Logatchev hydrothermal vent field,Mid-Atlantic Ridge 被引量:4
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作者 ZHOU HuaiYang WU ZiJun +2 位作者 PENG XiaoTong JIANG Lei TANG Song 《Chinese Science Bulletin》 SCIE EI CAS 2007年第15期2140-2146,共7页
During DY105-17 cruise onboard the R/V "Da Yang Yi Hao" in 2005,methane concentrations in the wa-ter column above Logachev hydrothermal vent field were measured by applying stripping/trapping-gas chromatogra... During DY105-17 cruise onboard the R/V "Da Yang Yi Hao" in 2005,methane concentrations in the wa-ter column above Logachev hydrothermal vent field were measured by applying stripping/trapping-gas chromatographic (GC) and the distinct methane plumes were detected. Results show that the back-ground methane concentration within the Logachev area is from 1.05 nmol/L to 1.68 nmol/L,signifi-cantly higher than the background level of the Atlantic abyssal plain of 0.4―0.5 nmol/L,suggesting that hydrothermal venting is a major source of dissolved methane to the ocean. The highest anomalies of methane concentrations in the water column range from 7.14 nmol/L to 113.9 nmol/L and occur just at 180―500 m above the seafloor. The distribution of methane concentration and the structural charac-teristics of hydrothermal plumes are strongly influenced by the supply of underlying hydrothermal fluids,the mixing process of ocean bottom currents and the microbial oxidation. Furthermore,the dif-ferences in distribution of methane plume between the station MAR-CTD3 and the other stations indi-cate a probable unknown hydrothermal vent site nearby. There occurs high concentration of methane along with temperature and nephelometry anomalies,which strongly confirms that the subtle meas-urement of methane concentration in water column is one of the effective ways to locate active sites of hydrothermal venting. 展开更多
关键词 甲烷 浓度异常 热气流 层离法
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Variation of Soil Labile Organic Carbon Pools along an Elevational Gradient in the Wuyi Mountains,China 被引量:5
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作者 徐侠 程晓莉 +3 位作者 周焱 骆亦其 阮宏华 汪家社 《Journal of Resources and Ecology》 CSCD 2010年第4期368-374,共7页
土壤活性有机碳(LOC)是一组活跃的化学物质,由于其较短的周转时间和对环境变化的敏感性在全球碳循环中发挥着重要的作用。但是,对活性有机碳在亚热带森林沿海拔梯度的空间变异还缺乏了解。在本研究中,我们测定了福建武夷山自然保护区不... 土壤活性有机碳(LOC)是一组活跃的化学物质,由于其较短的周转时间和对环境变化的敏感性在全球碳循环中发挥着重要的作用。但是,对活性有机碳在亚热带森林沿海拔梯度的空间变异还缺乏了解。在本研究中,我们测定了福建武夷山自然保护区不同海拔高度具有代表性的中亚热带常绿阔叶林(500 m)、针叶林(1150 m)、亚高山矮林(1750 m)以及高山草甸(2150 m)土壤不同土层(0-10,10-25和25-40 cm)中微生物可利用碳(MAC)、微生物量碳(MBC)、易氧化碳(ROC)、水溶性碳(WSOC)和轻组碳(LFC),并观测了相应的植物凋落物质量(LM),土壤温度和湿度。结果表明:沿海拔梯度的植被变化和土层深度变化对土壤活性有机碳有显著的影响。微生物可利用碳、微生物量碳、易氧化碳和水溶性碳在不同土层均沿海拔高度的增加而显著增加;而低海拔的常绿阔叶林和针叶林中轻组碳的含量高于亚高山矮林和高山草甸的轻组碳的含量。各土壤活性有机碳库均随土层的加深而减小。除轻组碳外,各碳库间存在着极显著的正相关(p【0.001)。轻组碳分别在低海拔(常绿阔叶林和针叶林)和高海拔(亚高山矮林和高山草甸)与各碳库显著相关。 展开更多
关键词 soil organic carbon labile organic carbon fractionation methods soil depth elevational gradient(vegetations)
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A new unequal-weighted triple-frequency first order ionosphere correction algorithm and its application in COMPASS 被引量:5
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作者 WenXiang Liu WeiHua Mou FeiXue Wang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第3期546-552,共7页
As the introduction of triple-frequency signals in GNSS,the multi-frequency ionosphere correction technology has been fast developing.References indicate that the triple-frequency second order ionosphere correction is... As the introduction of triple-frequency signals in GNSS,the multi-frequency ionosphere correction technology has been fast developing.References indicate that the triple-frequency second order ionosphere correction is worse than the dual-frequency first order ionosphere correction because of the larger noise amplification factor.On the assumption that the variances of three frequency pseudoranges were equal,other references presented the triple-frequency first order ionosphere correction,which proved worse or better than the dual-frequency first order correction in different situations.In practice,the PN code rate,carrier-to-noise ratio,parameters of DLL and multipath effect of each frequency are not the same,so three frequency pseudorange variances are unequal.Under this consideration,a new unequal-weighted triple-frequency first order ionosphere correction algorithm,which minimizes the variance of the pseudorange ionosphere-free combination,is proposed in this paper.It is found that conventional dual-frequency first-order correction algorithms and the equal-weighted triple-frequency first order correction algorithm are special cases of the new algorithm.A new pseudorange variance estimation method based on the three carrier combination is also introduced.Theoretical analysis shows that the new algorithm is optimal.The experiment with COMPASS G3 satellite observations demonstrates that the ionosphere-free pseudorange combination variance of the new algorithm is smaller than traditional multi-frequency correction algorithms. 展开更多
关键词 GNSS ionospheric delay ionosphere-free combination COMPASS
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Empirical modeling of ionospheric F2 layer critical frequency over Wakkanai under geomagnetic quiet and disturbed conditions 被引量:4
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作者 LIU Jing LIU LiBo +2 位作者 ZHAO BiQiang WAN WeiXing CHEN YiDing 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第5期1169-1177,共9页
The hourly values of the ionospheric F2 layer critical frequency, foF2, recorded at Wakkanai ionosonde station (45.4°N, 141.7°E) have been collected to construct a middle-latitude single-station model for ... The hourly values of the ionospheric F2 layer critical frequency, foF2, recorded at Wakkanai ionosonde station (45.4°N, 141.7°E) have been collected to construct a middle-latitude single-station model for forecasting foF2 under geomagnetic quiet and disturbed conditions. The module for the geomagnetic quiet conditions incorporates local time, seasonal, and solar vari- ability of climatological foF2 and its upper and lower quartiles. It is the first attempt to predict the upper and lower quartiles of foF2 to account for the notable day-to-day variability in ionospheric foF2. The validation statistically verifies that the model captures the climatological variations of foF2 with higher accuracy than IRI does. The storm-time module is built to capture the geomagnetic storm induced relative deviations of foF2 from the quiet time references. In the geomagnetically disturbed module, the storm-induced deviations are described by diumal and semidiumal waves, which are modulated by a modified magnetic activity index, the Kf index, reflecting the delayed responses of foF2 to geomagnetic activity forcing. The coeffi- cients of the model in each month are determined by fitting the model formula to the observation in a least-squares way. We provide two options for the geomagnetic disturbed module, including or not including Kalman filter algorithm. The Kalman filter algorithm is introduced to optimize these coefficients in real time. Our results demonstrate that the introduction of the Kalman filter algorithm in the storm time module is promising for improving the accuracy of predication. In addition, comparisons indicate that the IRI model prediction of the F2 layer can be improved to provide better performances over this region. 展开更多
关键词 Empirical modeling Kalman f'dter ionospheric storm
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The variation of the estimated GPS instrumental bias and its possible connection with ionospheric variability 被引量:14
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作者 ZHANG DongHe SHI Hao +3 位作者 JIN YaQi ZHANG Wei HAO YongQiang XIAO Zuo 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第1期67-79,共13页
Based on the analysis of the satellite DCB data estimated by our method and the Center for Orbit Determination in Europe(CODE)from 1999 to 2011,the features of the temporal variation of differential code biases(DCB)ar... Based on the analysis of the satellite DCB data estimated by our method and the Center for Orbit Determination in Europe(CODE)from 1999 to 2011,the features of the temporal variation of differential code biases(DCB)are studied.Summarily,there are three types of variations in DCB on different time scales.The first one is the day-to-day variation that exhibits more obviously in solar maximum years.The second one is the variation with about one year periodic variation that behaves more obviously from 1999 to 2004.The last one is the monotonously descending tendency from 1999 to 2010.Considering the basic ionospheric approximation in DCB estimation method,the features of the variability of the ionospheric morphology from 1999to 2010 are also displayed based on the ionospheric characteristic parameters.It can be concluded that the day-to-day and annual variation of the estimated global positioning system(GPS).DCB is related to the ionospheric variability.The variation of DCBs on solar cycle time scale includes the real hardware DCBs and pseudo-DCBs induced by ionospheric variation.No doubt,these kinds of"pseudo"variations of DCB will affect the precision of ionospheric total electron content(TEC)derived from the GPS data.In addition,this study is helpful for evaluating the influence of ionospheric weather on TEC derivation and is also useful for developing one estimation method of DCB with more stability and precision through introducing a more practical ionospheric model. 展开更多
关键词 DCB ionospheric variability GPS instrumental bias solar cycle
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