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Hole cleaning evaluation and installation spacing optimization of cuttings bed remover in extended-reach drilling
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作者 Shuo Peng Wen-Jun Huang De-Li Gao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期2005-2022,共18页
In extended-reach or long-horizontal drilling,cuttings usually deposit at the bottom of the annulus.Once cuttings accumulate to a certain thickness,complex problems such as excessive torque and drag,tubing buckling,an... In extended-reach or long-horizontal drilling,cuttings usually deposit at the bottom of the annulus.Once cuttings accumulate to a certain thickness,complex problems such as excessive torque and drag,tubing buckling,and pipe stuck probably occur,which results in a lot of non-productive time and remedial operations.Cuttings bed remover can efficiently destroy deposited cuttings in time through hydraulic and mechanical stirring effects.This paper aims to build a method for hole cleaning evaluation and installation spacing optimization of cuttings bed remover to improve the wellbore cleaning effect.Firstly,a Computational Fluid Dynamics approach with Eulerian—Eulerian multiphase model was utilized to investigate the mechanism of cuttings transportation,and a new type of cuttings bed remover was designed.Next,an evaluation method of hole cleaning effect of remover was established.After that,the effects of several drilling parameters on hole cleaning including flow rate of drilling fluid,rotational speed of drillpipe,rate of penetration,wellbore size,rheological property of drilling fluid,and remover eccentricity on the performance of cuttings bed remover were investigated.The results demonstrate that the new type of remover with streamline blade performs better than conventional removers.The efficiency of hole cleaning is greatly improved by increasing the rotational speed of drillpipe,flow rate of drilling fluid,remover eccentricity,and 6 rpm Fann dial reading for drilling fluid.While higher rate of penetration and large wellbore size result in worse hole cleaning.These findings can serve as an important guide for the structure optimization design of cuttings bed remover and installation spacing of removers. 展开更多
关键词 Extended-reach drlling Drilling hydraulics Cuttings transport Hole cleaning Cuttings bed remover
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Mechanism to remove oxide inclusions from molten aluminum by solid fluxes refining method 被引量:5
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作者 Cong Li Jian-guo Li +1 位作者 Yi-zhe Mao Jia-cheng Ji 《China Foundry》 SCIE 2017年第4期233-243,共11页
A novel flux charging method and a crucible quenching method were employed to study the mechanism of solid fluxes refining method regarding the removal of oxide inclusions(Al_2O_3) from molten aluminum. Electrochemica... A novel flux charging method and a crucible quenching method were employed to study the mechanism of solid fluxes refining method regarding the removal of oxide inclusions(Al_2O_3) from molten aluminum. Electrochemical polishing method was adopted to prepare surfaces of the samples. Through experiments, the morphology of the residual solidified flux in the solidified samples as well as the wetting action of the molten flux during refining were observed for the first time. Three wetting regimes denoted by absorbing regime, engulfing regime and penetration regime correlating with the removal of oxide films(the most typical and common oxide inclusions in molten aluminum) were proposed in terms of different types and distributions of oxide films and different size ratios of the molten flux to oxide films. Particularly, from a thermodynamic point of view, for the first time, the penetration regime provided concrete evidence that the practical oxide inclusions can be wet by molten flux under ambient fluid of molten aluminum. A spreading model was proposed, according to which ingredients and size parameters of practical solid fluxes can be optimized. 展开更多
关键词 MELT quality INCLUSIONS removal MELT treatment FLUXES aluminum CASTING
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Remove cooking fume using catalytic combustion over Pt/La-Al_2O_3 被引量:3
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作者 WANG Jian-li ZHONG Jun-bo GONG Mao-chu LIU Zhi-min ZHAO Ming CHEN Yao-qiang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第6期644-646,共3页
Five monolithic catalysts with low noble metal content were prepared by irnmerge method (Pt/γ=Al2O3, Pt/La-Al2O3, Pt/YSZ-AI203, Pt+Pd/La-Al2O3 and Pd/La-Al2O3) and their activity measurements were carried out in a... Five monolithic catalysts with low noble metal content were prepared by irnmerge method (Pt/γ=Al2O3, Pt/La-Al2O3, Pt/YSZ-AI203, Pt+Pd/La-Al2O3 and Pd/La-Al2O3) and their activity measurements were carried out in a conventional fixed-bed flow reactor. The results show that La-Al2O3 can promote activity of the prepared catalysts and can decrease the complete conversion temperature of cooking fume. The Pt/La-Al2O3 catalyst has the highest activity and can be applied in wide range of gas hourly space velocity (GHSV). Some characterizations (XRD, TPR) were carried out with the objective to explain differences in catalytic behaviors. The prepared catalyst showed a great potential for application. 展开更多
关键词 cooking fume monolithic catalyst remove catalytic combustion
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A modified approach to actively remove high viscosity silicone oil through 23-gauge cannula 被引量:4
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作者 Zong-Ming Song Xu-Ting Hu +3 位作者 Lei Wang Zhi-Xiang Hu Pei-Quan Zhao Ding Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第9期1294-1298,共5页
AIM:To report a simple approach to actively remove high viscosity silicone oil through a 23-gauge cannula via pars plana.METHODS:Forty-eight eyes of 48 patients underwent silicone oil(5700 centistokes) removal(SO... AIM:To report a simple approach to actively remove high viscosity silicone oil through a 23-gauge cannula via pars plana.METHODS:Forty-eight eyes of 48 patients underwent silicone oil(5700 centistokes) removal(SOR) were enrolled.A section of blood transfusion set was prepared to connect a standard 23-gauge cannula and vitrectomy machine.Silicone oil was removed with suction of500-mm Hg vacuum through the cannula.Main outcome measures were SOR duration,number of sutured sites,intraocular pressure(IOP),best-corrected visual acuity(BCVA),and complications.RESULTS:Silicone oil was successfully removed in all cases.The mean SOR time was 5.70±0.85 min.Nine eyes(18.75%) needed suture partial sclerotomies.No intraoperative complications were noted.Transient hypotony(≤8 mm Hg) was seen in 3 eyes(6.25%) on postoperative day 1,but all resolved within 1wk.Retinal reattachment was achieved in all cases and no other postoperative complications were noted during 3-month following-up.BCVA at the final visit improved or stabilized in all patients comparing to the preoperative level.CONCLUSION:Active removal of high viscosity silicone oil through a 23-gauge instrument cannula jointed with blood transfusion set is a practical and reliable technique when considering two sides of efficacy and safety. 展开更多
关键词 silicone oil active removal 23-gauge pars plana
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Using a zeolite medium biofilter to remove organic pollutant and ammonia simultaneously 被引量:2
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作者 TIANWen-hua WENXiang-hua QIANYi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期90-93,共4页
A pilot scale zeolite medium biological aerated filter(ZBAF) was designed and used to treat municipal wastewater. It showed that ZBAF could simultaneously remove chemical oxygen demand(COD), ammonia-N and turbidity to... A pilot scale zeolite medium biological aerated filter(ZBAF) was designed and used to treat municipal wastewater. It showed that ZBAF could simultaneously remove chemical oxygen demand(COD), ammonia-N and turbidity to satisfied degree at a hydraulic retention time(HRT) of 0.95 h. Their average removal efficiencies were 73.9%, 88.4% and 96.2% with the corresponding average effluent concentrations of 43.4 mg/L, 3.5 mg/L and 3.7 NTU, respectively. These effluent items met with the water quality standard of the treated water reused for cooling water. The COD removal volumetric loading rate increased proportionally with its applied volumetric loading rate with its maximum of 7.1 kg/(m 3·d). Ammonia-N removal loading rate also increased proportionally with its applied loading rate at HRT of longer than 0.95 h and the feasible maximum removal loading rate was 0.9 kg/(m 3·d). The COD loading rate did not affect the ammonia-N removal efficiency significantly when it was lower than 5.5 kg/(m 3·d). ZBAF has good application prospect for its low cost and high removal efficiency in the future. 展开更多
关键词 ammonia-N removal biological aerated filter hydraulic retention time natural zeolite volumetric loading rate
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Remove volatile organic compounds(VOCs) with membrane separation techniques 被引量:1
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作者 ZhanL WangHX 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第2期181-187,共7页
Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techni... Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techniques are an efficient and energy saving technology. Vapor permeation can be applied to recovery of organic solvents from exhaust streams. Membrane contactor could be used for removing or recovering VOCs from air or wastewater. Pervaporation and vapor permeation are viable methods for removing VOCs from wastewater to yield a VOC concentrate which could either be destroyed by conventional means, or be recycled for reuse. 展开更多
关键词 volatile organic compounds(VOCs) membrane separation techniques remove
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Iron-Modification of Pyroclastic Material from PCCVC Eruption (Chile): Characterization and Application to Remove Arsenic from Groundwater 被引量:1
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作者 María J. González Lia Botto +2 位作者 María E. Canafoglia Laura Coccaro Edgardo Soto 《Journal of Environmental Protection》 2015年第10期1124-1133,共10页
Pyroclastic material from the PCCVC eruption (Chile) was modified with iron (III) solutions leading to the formation of ferrihydrite surface deposits. The aim of the chemical treatment was to prepare an adsorbent to r... Pyroclastic material from the PCCVC eruption (Chile) was modified with iron (III) solutions leading to the formation of ferrihydrite surface deposits. The aim of the chemical treatment was to prepare an adsorbent to remove arsenic from water by using low-cost mineral wastes. Physicochemical characterization of original and modified materials was carried out by XRD, BET-N2 adsorption, SEM-EDS microscopy and ICP-AES chemical analysis. The modified ash revealed that the increase of bulk iron content was close to 5% (expressed as Fe2O3) whereas surface values were 20.6% Fe2O3. Surface properties showed an increase of BET specific surface with prevalence of mesopores and an increase of total pore volume attributed to presence of nanoscopic iron phase. Kinetic and equilibrium studies were directed to optimize the operative conditions related to the material adsorptive capacity for removing arsenate species. Hence, the adsorbent dose, contact time, pH, stirring and sedimentation were evaluated in batch process. The optimal adsorption dose was 40 g ·L-1 and the solid-liquid contact time was stirring (1 h) and sedimentation (23 h), enough to ensure an adequate turbidity value valid for a pH range between 3.77 and 8.95. The analysis of the isotherm equilibrium by using the Langmuir linear method showed a R2 = 0.995 value. The performance of the treatment to remove arsenic by using a cost-effective adsorbent prepared from volcanic material is a promising technology to apply in the environmental field. 展开更多
关键词 VOLCANIC Ash Iron MODIFICATION ARSENIC removal GROUNDWATER
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Chitosan Removes Toxic Heavy Metal Ions from Cigarette Mainstream Smoke 被引量:2
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作者 ZHOU Wen XU Ying +1 位作者 WANG Dongfeng ZHOU Shilu 《Journal of Ocean University of China》 SCIE CAS 2013年第3期509-514,共6页
This study investigated the removal of heavy metal ions from cigarette mainstream smoke using chitosan. Chitosan of various deacetylation degrees and molecular weights were manually added to cigarette filters in diffe... This study investigated the removal of heavy metal ions from cigarette mainstream smoke using chitosan. Chitosan of various deacetylation degrees and molecular weights were manually added to cigarette filters in different dosages. The mainstream smoke particulate matter was collected by a Cambridge filter pad, digested by a microwave digestor, and then analyzed for contents of heavy metal ions, including As(Ill/V), Pb(II), Cd(II), Cr(III/VI) and Ni(II), by graphite furnace atomic absorption spectrometry (GFAAS). The results showed that chitosan had a removal effect on Pb(II), Cd(II), Cr(III/VI) and Ni(II). Of these, the percent re- moval of Ni(II) was elevated with an increasing dosage of chitosan. Chitosan of a high deace tylation degree exhibited good binding performance toward Cd(II), Cr(III/VI) and Ni(II), though with poor efficiency for Pb(II). Except As(III/V), all the tested metal ions showed similar tendencies in the growing contents with an increasing chitosan molecular weight. Nonetheless, the percent removal of Cr(III/VI) peaked with a chitosan molecular weight of 200 kDa, followed by a dramatic decrease with an increasing chitosan mo- lecular weight. Generally, chitosan had different removal effects on four out of five tested metal ions, and the percent removal of Cd(II), Pb(II), Cr(III/VI) and Ni(II) was approximately 55%, 45%, 50%, and 16%, respectively. In a word, chitosan used in cigarette filter can remove toxic heavy metal ions in the mainstream smoke, improve cigarette safety, and reduce the harm to smokers. 展开更多
关键词 CHITOSAN heavy metal ions cigarette mainstream smoke percent removal
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Effects of structural and operating parameters of ECP fan on dust particles removed in the transition flow regime 被引量:2
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作者 Shiqiang Chen Youming Chen +2 位作者 Haiqiao Wang Ronghua Liu Haijiao Cui 《International Journal of Coal Science & Technology》 EI CAS 2014年第4期441-449,共9页
An enclosed cyclone passageway(ECP)dust-collecting fan is discussed.The ECP fan separates dust by centrifugal force originating from a driven spiral airflow,and its design takes the constraints of Chinese underground ... An enclosed cyclone passageway(ECP)dust-collecting fan is discussed.The ECP fan separates dust by centrifugal force originating from a driven spiral airflow,and its design takes the constraints of Chinese underground coal mines into consideration.Using the force equilibrium law,a general equation for dust removal in the centrifugal dust removal section(CDRS)of the ECP fan is deduced.This general equation is simplified using the CDRS structure and the fan operating parameters and is analysed numerically.The attractive results show that increases in the airflow rate of the fan,the structural ratio of the ECPs and the radius of the extended axis can improve the dust removal performance of the CDRS.Furthermore,the effects of the structural ratio and the radius on dust removal dominate over that of the flow rate,and the effect of the structural ratio is more significant than that of the radius. 展开更多
关键词 Dust removal Driven spiral airflow Structural and operating parameters ECP fan
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Iron Activation of Natural Aluminosilicates to Remove Arsenic from Groundwater 被引量:2
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作者 Irma Lia Botto Maria Jose Gonzalez +1 位作者 Delia Gazzolli Edgardo Luis Soto 《Journal of Environmental Science and Engineering(A)》 2013年第12期744-752,共9页
Low-cost adsorbents constituted by Fe-modified-aluminosilicates (laminar and zeolite type minerals) were developed and characterized to be used in the arsenic removal from groundwater. Iron activation was carried o... Low-cost adsorbents constituted by Fe-modified-aluminosilicates (laminar and zeolite type minerals) were developed and characterized to be used in the arsenic removal from groundwater. Iron activation was carried out "in situ" by the synthesis and deposition of mesoporous ferrihydrite. Natural iron-rich aluminosilicate was used as reference. All samples were characterized by X-ray diffraction, Raman spectroscopy, BET N2-adsorption, SEM-EDS microscopy and ICP chemical analysis. Experimental results of arsenic sorption showed that iron-poor raw materials were not active, unlike iron activated samples. The iron loading in all activated samples was below 5% (expressed as Fe203), whereas the removal capacity of these samples reaches between 200-700 gg of As by g of adsorbent, after reusing between 17 cycles and 70 cycles up to adsorbent saturation. Differences can be associated to mineral structure and to the surface charge modification by iron deposition, affecting the attraction of the As-oxoanion. On the basis of low-cost raw materials, the easy chemical process for activation shows that these materials are potentially attractive for As(V) removal. Likewise, the activation of clay minerals, with natural high content of iron, seems to be a good strategy to enhance the arsenic adsorption ability and consequently the useful life of the adsorbent. 展开更多
关键词 Arsenic removal iron activation aluminosilicates.
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AXIAL HEAT CONDUCTION MODEL TO PREDICT MAXIMUM HEAT REMOVE OF MINIATURE HEAT PIPE BASED ON GREY MODEL THEORY 被引量:3
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作者 Tsai Mengchang Chang Shinhsing Kang Shungwen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期477-481,共5页
Computer chip is always accompanied by the increase of heat dissipation and miniaturization. The miniature heat pipes are widely used in notebook computer to resolve the heat dissipation problems. Maximum heat removed... Computer chip is always accompanied by the increase of heat dissipation and miniaturization. The miniature heat pipes are widely used in notebook computer to resolve the heat dissipation problems. Maximum heat removed model of miniature heat pipes building by grey model is presented. In order to know the foundation for modeling, the smooth grade of error examination is inquired and the accuracy of grey relational grade is verified. The model can be used to select a suitable heat pipes to solve electric heat problems in the future. Final results show that the grey model only needs four experiment data and its error value is less than 10%, further, it is better than computational fluid dynamics (CFD) model. 展开更多
关键词 Maximum heat removed model Miniature heat pipe Grey model theory Computational fluid dynamics (CFD) Grey relational grade
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Applications of Bias-removed Ensemble Mean in the Gale Forecasts over the Yellow Sea and the Bohai Sea 被引量:3
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作者 朱桦 智协飞 俞永庆 《Meteorological and Environmental Research》 CAS 2010年第11期4-8,共5页
Based on the daily sea surface wind field prediction data of Japan Meteorological Agency(JMA) forecast model,National Centers for Environmental Prediction(NCEP GFS) model and U.S.Navy Operational Global Atmospheric Pr... Based on the daily sea surface wind field prediction data of Japan Meteorological Agency(JMA) forecast model,National Centers for Environmental Prediction(NCEP GFS) model and U.S.Navy Operational Global Atmospheric Prediction System(NOGAPS) model at 12:00 UTC from June 28 to August 10 in 2009,the bias-removed ensemble mean(BRE) was used to do the forecast test on the sea surface wind fields,and the root-mean-square error(RMSE) was used to test and evaluate the forecast results.The results showed that the BRE considerably reduced the RMSEs of 24 and 48 h sea surface wind field forecasts,and the forecast skill was superior to that of the single model forecast.The RMSE decreases in the south of central Bohai Sea and the middle of the Yellow Sea were the most obvious.In addition,the BRE forecast improved evidently the forecast skill of the gale process which occurred during July 13-14 and August 7 in 2009.The forecast accuracy of the wind speed and the gale location was also improved. 展开更多
关键词 Bias-removed ensemble mean Gale over the Yellow Sea and the Bohai Sea Forecast skill China
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Combination of Ozonation Process and Absorption through Membrane Contactor Using Natural Hot Spring Water as Absorbent to Remove Ammonia from Wastewater 被引量:1
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作者 Sutrasno Kartohardjono Milasari Herdiana Putri Sri Fahmiati Elvina Fitriasari Candrika Ajeng SetijoBismo 《Journal of Environmental Science and Engineering(A)》 2012年第4期428-433,共6页
Ammonia in wastewater is a major pollutant produced in industrial and agricultural wastewaters. Ammonia is often removed by conventional technologies such as pack tower aeration, biological treatment or adsorption as ... Ammonia in wastewater is a major pollutant produced in industrial and agricultural wastewaters. Ammonia is often removed by conventional technologies such as pack tower aeration, biological treatment or adsorption as ammonium ion onto zeolites. In many cases, conventional methods are very costly and inefficient, and therefore there is a need for an alternative separation technique for more efficient removal of ammonia from wastewaters. The aim of this study is to investigate the performance of combination of ozonation and absorption through membrane processes to remove ammonia from wastewater using NHSW (natural hot spring water) as absorbent. Experimental results show that hollow fiber membrane contactor has potential application for ammonia removal from wastewater. Operating variables such as time and pH of absorbent solution are found to remarkably influence the removal process efficiency.. Based on experimental results ozonation can improve ammonia removal efficiency through hollow fiber membrane contactor. Ammonia removal efficiencies and overall mass transfer coefficients increase with decreasing pH of absorbent solution. 展开更多
关键词 AMMONIA mass transfer membrane OZONATION removal efficiency.
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Clinical Observation on Influence of Chinese Medicines for Promoting Blood Circulation to Remove Blood Stasis on FIB and DD in Plasma of Patients with Cerebral Thrombosis 被引量:3
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作者 梁晖 陈甦 +1 位作者 陈少芳 段树民 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2002年第4期256-259,共4页
to study the influence of Chinese medicines for promoting blood circulation to remove blood stasis on fibrinogen(FIB)and D-dimer(DD)in plasma of patients with cerebral thrombosis. Method:73 inpatients with acute cereb... to study the influence of Chinese medicines for promoting blood circulation to remove blood stasis on fibrinogen(FIB)and D-dimer(DD)in plasma of patients with cerebral thrombosis. Method:73 inpatients with acute cerebral thrombosis were randomly divided into a control group of 34 cases and a treatment group of 39 cases.The content of FIB and DD in plasma was detected before treatment and on the 7th and 14th days after treatment.Result:FIB content in plasma after treatment was lower than that before treatment in the control group(P<0.01)and more remarkable in the treatment group(P<0.001).There was an obvious difference in DD content before and after treatment in both groups.DD content on the 7th and 14th days after treatment in the treatment group was obviously higher than that in the control group(P<0.01 and P<0.05 respectively). Conclusion:Chinese medicines for promoting blood circulation to remove blood stasis can reduce the FIB content in plasma of patients with cerebral thrombosis,raise the DD content in plasma, cause the peak of DD content appear earlier and obviously improve hypercoagulability of blood in patients with cerebral thrombosis. 展开更多
关键词 FIB Clinical Observation on Influence of Chinese Medicines for Promoting Blood Circulation to remove Blood Stasis on FIB and DD in Plasma of Patients with Cerebral Thrombosis DD
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Estimate of Heavy Metals in Soil with Non-Soil Removed
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作者 Ji Jian Yao Fang +3 位作者 Wei-Le Li Qian-Yu Chen Heng-Yu Tian Shuang-Lin You 《Journal of Data Analysis and Information Processing》 2017年第4期140-155,共16页
Quantifying and mapping heavy metals’ concentrations in the soil are important in monitoring and managing heavy metal pollution in the mining areas. However, the cover on the soil acts as a balk when retrieving infor... Quantifying and mapping heavy metals’ concentrations in the soil are important in monitoring and managing heavy metal pollution in the mining areas. However, the cover on the soil acts as a balk when retrieving information from soil. In order to retrieve heavy metal pollution precisely and quickly from hyperspectral images, this study presents a new method to remove non-soil information based NDVI from hyper-spectral and multi-spectral images. The method assumed that the mixed objects in each pixel of remote sensing images are composed only of soil and vegetation-based non-soil end-generational endmembers, then, the soil information of each pixel can be compensated with the non-soil information removed based on its NDVI. Thus, the soil DN value can be corrected to retrieve soil information more precisely. The method has been used on the Hyperion image in June 8, 2002 and the Gaofen-2 (GF-2) image in February 14, 2016 to retrieve the heavy metals’ contents in Bai-ma and De-sheng mining areas, Miyi County, Sichuan Province. From the non-soil information removed images, the R2 and RMSE of the models of estimating Cr, Ag, Cu and Ba in soil are 0.68, 0.724, 0.71, 0.695 and 75.96, 0.03, 52.88, 284.70 respectively. From the original images, the R2 and RMSE of the models of estimating Cr, Ag, Cu and Ba in soil are 0.67, 0.385, 0.425, 0.406 and 80.11, 0.18, 53.43, 396.49 respectively. The retrieval results show that the non-soil information removed images are superior to original images in soil heavy metals’ contents retrieval. This indicates that this method is feasible, and it can be used in soil information retrieval. 展开更多
关键词 Non-Soil Information removal HEAVY Metal NDVI Spectral UNMIXING
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Formation and Removement Mechanism of Haze Defects on(111)p-type Silicon Wafers
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作者 徐岳生 李养贤 +3 位作者 刘彩池 鞠玉林 唐建 朱则韶 《Rare Metals》 SCIE EI CAS CSCD 1994年第1期31-36,共6页
The haze defects on p-type (111) silicon wafers were investigated by means of chemical etching, Fouriertransform infra-red microscopy (FTIR), spreading resistance measurement. secondary ion mass spectroscopy(SLMS), tr... The haze defects on p-type (111) silicon wafers were investigated by means of chemical etching, Fouriertransform infra-red microscopy (FTIR), spreading resistance measurement. secondary ion mass spectroscopy(SLMS), transmission electron microscopy (TEM) equipped with an energy-dispersive X-ray spectrometer(EDX). The haze defects are the precipitates of silicide of metal impurities (Fe, Ni) on the wafer surface.The formation of haze defects can efficiently be inhibited by utilizing the technology of fast neutronirradiation combined with the internal gettering (IG), and then, the formation and removement mechanismof the haze defects have been discussed in this paper. 展开更多
关键词 Oxidation haze defects Formation and removement mechanism Fast-neutron irradiation Internal gettering (IG)
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Model for Quantitative Evaluation and Prediction of the Concentration of Phosphorus Removed during Pyro-Hydro Beneficiation of Haematite
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作者 C. I. Nwoye M. C. Menkiti +1 位作者 E. Obidiegwu N. E. Nwankwo 《Journal of Minerals and Materials Characterization and Engineering》 2011年第7期637-650,共14页
This paper presents a model derived for quantitative evaluation and prediction of the concentration of phosphorus removed during pyro-hydro beneficiation of iron oxide ore. Potassium hydroxide was used as the leaching... This paper presents a model derived for quantitative evaluation and prediction of the concentration of phosphorus removed during pyro-hydro beneficiation of iron oxide ore. Potassium hydroxide was used as the leaching solution and the reaction vessel containing the solution and ore was heated at a temperature of 600℃ for 10 minutes. The results of the investigation indicates that the model;P = (e0.7827) S predicts the concentration of phosphorus removed, based on the concentration of sulphur simultaneously removed. It was observed that the validity of the model is rooted in the expression lnP = lnN + lnS where both sides of the expression are approximately equal to 4. The maximum deviation of the model-predicted concentration of removed phosphorus from the corresponding concentration obtained from the experiment was less than 3%. The concentrations of phosphorus removed per unit mass-input of iron oxide ore as obtained from experiment and derived model are 0.8917 and 1.0354 mg/kg g-1 respectively. Similarly, the concentrations of phosphorus removed per unit concentration of removed sulphur as obtained from experiment and derived model are 1.8838 and 2.1874 mg/kg (mg/kg)-1 respectively. This implies that the concentration of phosphorus removed is approximately equal to the concentration of simultaneously removed sulphur during the beneficiation process. 展开更多
关键词 MODEL PHOSPHORUS removed Pyro-Hydrometallurgy Potassium Hydroxide Iron Oxide Ore.
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New methods to remove baseline drift in trapezoidal pulse shaping 被引量:3
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作者 洪旭 马英杰 +4 位作者 周建斌 陈铁光 胡云川 万新峰 杜鑫 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第5期58-62,共5页
Trapezoidal pulse shaping algorithm is widely applied to improve signal-to-noise ratio(SNR), throughput and energy resolution with the properties of noise suppression, pile-up pulse separation and ballistic deficit co... Trapezoidal pulse shaping algorithm is widely applied to improve signal-to-noise ratio(SNR), throughput and energy resolution with the properties of noise suppression, pile-up pulse separation and ballistic deficit correction. The algorithm can be acquired by z transform method which is easier for derivation. However, the baseline drift of trapezoidal pulse appears because the noise superimposes on the input signal. In this paper,two new methods based on convergence analysis and noise suppression are proposed to remove the baseline drift resulting from trapezoidal pulse shaping. Simulations and experimental tests are carried out to verify the methods. The results demonstrate that the proposed methods can remove baseline drift in trapezoidal pulse shaping. 展开更多
关键词 梯形脉冲 基线漂移 脉冲整形 高信噪比 噪声抑制 能量分辨率 收敛性分析 弹道修正
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The Application of Cold Banding Technology for Dust Removed From BOF Gas Using Dry Dedusting Technology
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作者 Tang Weijun Zhang Yong Ma Gangping 《Meteorological and Environmental Research》 CAS 2015年第1期14-16,共3页
Firstly, physical and chemical properties of dust removed from BOF gas are analyzed, and then the cold banding technology of dust removed from BOF gas and its application are introduced. Tests have proved that using c... Firstly, physical and chemical properties of dust removed from BOF gas are analyzed, and then the cold banding technology of dust removed from BOF gas and its application are introduced. Tests have proved that using cooled agglomerated pellets made of the dust removed from BOF gas and small amounts of modified starch as a coolant and slagging agent in steel production can bring about considerable economic, social and environmental benefits. 展开更多
关键词 BOF gas Dust removed from BOF gas using dry dedusting technology Cold banding Steelmaking China
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Background removal from global auroral images:Data-driven dayglow modeling 被引量:1
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作者 A.Ohma M.Madelaire +4 位作者 K.M.Laundal J.P.Reistad S.M.Hatch S.Gasparini S.J.Walker 《Earth and Planetary Physics》 EI CSCD 2024年第1期247-257,共11页
Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth environment.However,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but... Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth environment.However,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by sunlight.Nightglow emissions and scattered sunlight can contribute to the background signal.To fully utilize such images in space science,background contamination must be removed to isolate the auroral signal.Here we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical harmonics.The approach is robust,flexible,and iteratively deselects outliers,such as auroral emissions.The final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the dayglow.We demonstrate the model by using the three far ultraviolet cameras on the Imager for Magnetopause-to-Aurora Global Exploration(IMAGE)mission.The method can be applied to historical missions and is relevant for upcoming missions,such as the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission. 展开更多
关键词 AURORA dayglow modeling global auroral images far ultraviolet images dayglow removal
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