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The AVO Effect of Formation Pressure on Time-Lapse Seismic Monitoring in Marine Carbon Dioxide Storage
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作者 Fan Wu Qingping Li +1 位作者 Yufa He Jingye Li 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第3期645-655,共11页
The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the informatio... The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the information of formation pressure can be response in the seismic data. Therefore, it is possible to monitor the formation pressure using time-lapse seismic method. Apart from formation pressure, the information of porosity and CO_(2) saturation can be reflected in the seismic data. Here, based on the actual situation of the work area, a rockphysical model is proposed to address the feasibility of time-lapse seismic monitoring during CO_(2) storage in the anisotropic formation. The model takes into account the formation pressure, variety minerals composition, fracture, fluid inhomogeneous distribution, and anisotropy caused by horizontal layering of rock layers(or oriented alignment of minerals). From the proposed rockphysical model and the well-logging, cores and geological data at the target layer, the variation of P-wave and S-wave velocity with formation pressure after CO_(2) injection is calculated. And so are the effects of porosity and CO_(2) saturation. Finally, from anisotropic exact reflection coefficient equation, the reflection coefficients under different formation pressures are calculated. It is proved that the reflection coefficient varies with pressure. Compared with CO_(2) saturation, the pressure has a greater effect on the reflection coefficient. Through the convolution model, the seismic record is calculated. The seismic record shows the difference with different formation pressure. At present, in the marine CO_(2) sequestration monitoring domain, there is no study involving the effect of formation pressure changes on seismic records in seafloor anisotropic formation. This study can provide a basis for the inversion of reservoir parameters in anisotropic seafloor CO_(2) reservoirs. 展开更多
关键词 Time-lapse seismic monitoring Marine carbon dioxide storage AVO modeling Formation pressure Anisotropic Rockphysical model
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Carbon dioxide partial pressure and carbon fluxes of air-water interface in Taihu Lake, China 被引量:2
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作者 范成新 胡维平 +3 位作者 Phillip W. Ford 陈宇炜 瞿文川 张路 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第1期29-38,共10页
To obtain carbon dioxide (CO2) flux between water-air interface of Taihu lake, monthly water samplers at 14 sites and the local meteorological data of the lake were collected and analyzed in 1998. Carbon dioxide par... To obtain carbon dioxide (CO2) flux between water-air interface of Taihu lake, monthly water samplers at 14 sites and the local meteorological data of the lake were collected and analyzed in 1998. Carbon dioxide partial pressures (pCO2) at air-water interface in the lake were calculated using alkalinity, pH, ionic strength, active coefficient, and water temperature. The carbon fluxes at different sublakes and areas were estimated by concentration gradient between water and air in consideration of Schmidt numbers of 600 and daily mean windspeed at 10 m above water surface. The results indicated that the mean values of pCO2 in Wuli Lake,Meiliang Bay, hydrophyte area, west littoral zone, riverine mouths, and the open lake areas were 1 807.8±1 071.4(mean±standard deviation)μatm (latm=1.013 25×10^5pa), 416.3±217.0μatm, 576.5±758.8μatm, 304.2±9.43.5μatm, 1 933.6±1 144.7 μatm, and 448.5±202.6μatm, respectively. Maximum and minimum pCO2 values were found in the hypertrophic (4 053.7μatm) and the eutrophic (3.2 μatm) areas. The riverine mouth areas have the maximum fluxes (82.0±62.8 mmol/m^2a). But there was no significant difference between eutrophic and mesotrophic areas in pCO2 and the flux of CO2. The hydrophyte area, however, has the minimum (--0.58±12.9mmol/m^2a). In respect to CO2 equilibrium, input of the rivers will obviously influence inorganic carbon distribution in the riverine estuary. For example, the annual mean CO2 flux in Zhihugang River estuary was 19 times of that in Meiliang Bay, although the former is only a part of the latter. The sites in the body of the lake show a clear seasonal cycle with pCO2 higher than atmospheric equilibrium in winter, and much lower than atmospheric in summer due to CO2 consumption by photosynthesis. The CO2 amount of the net annual evasion that enters the atmosphere is 28.42×10^4 t/a, of which those from the west littoral zone and the open lake account for 53.8% and 36.7%, respectively. 展开更多
关键词 carbon dioxide partial pressure air-water interface carbon flux trophic area river input Taihu Lake
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A Cu-Pd alloy catalyst with partial phase separation for the electrochemical CO_(2) reduction reaction
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作者 Gyeong Ho Han Jung Yong Seo +4 位作者 Minji Kang Myung-gi Seo Youngheon Choi Soo Young Kim Sang Hyun Ahn 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期8-15,I0001,共9页
Cu catalysts can convert CO_(2) through an electrochemical reduction reaction into a variety of useful carbon-based products.However,this capability provides an obstacle to increasing the selectivity for a single prod... Cu catalysts can convert CO_(2) through an electrochemical reduction reaction into a variety of useful carbon-based products.However,this capability provides an obstacle to increasing the selectivity for a single product.Herein,we report a simple fabrication method for a Cu-Pd alloy catalyst for use in a membrane electrode assembly(MEA)-based CO_(2) electrolyzer for the electrochemical CO_(2) reduction reaction(ECRR)with high selectivity for CO production.When the composition of the Cu-Pd alloy catalyst was fabricated at 6:4,the selectivity for CO increased and the production of multi-carbon compounds and hydrogen is suppressed.Introducing a Cu-Pd alloy catalyst with 6:4 ratio as the cathode of the MEAbased CO_(2) electrolyzer showed a CO faradaic efficiency of 92.8%at 2.4 V_(cell).We assumed that these results contributed from the crystal planes on the surface of the Cu-Pd alloy.The phases of the Cu-Pd alloy catalyst were partially separated through annealing to fabricate a catalyst with high selectivity for CO at low voltage and C_(2)H_4 at high voltage.The results of CO-stripping testing confirmed that when Cu partially separates from the lattice of the Cu-Pd alloy,the desorption of~*CO is suppressed,suggesting that C-C coupling reaction is favored. 展开更多
关键词 Cu-Pd catalyst ELECTRODEPOSITION Electrochemical carbon dioxide reduction partial phase separation Membrane electrode assembly-based electrolyzer
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Experimental Research on Supercritical Carbon Dioxide Fracturing of Sedimentary Rock:A Critical Review 被引量:1
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作者 ZHENG Bowen QI Shengwen +4 位作者 LU Wei GUO Songfeng WANG Zan YU Xin ZHANG Yan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第3期925-945,共21页
Supercritical carbon dioxide(ScCO_(2))fracturing has great advantages and prospects in both shale gas exploitation and CO_(2)storage.This paper reviews current laboratory experimental methods and results for sedimenta... Supercritical carbon dioxide(ScCO_(2))fracturing has great advantages and prospects in both shale gas exploitation and CO_(2)storage.This paper reviews current laboratory experimental methods and results for sedimentary rocks fractured by ScCO_(2).The breakdown pressure,fracture parameters,mineral composition,bedding plane angle and permeability are discussed.We also compare the differences between sedimentary rock and granite fractured by ScCO_(2),ultimately noting problems and suggesting solutions and strategies for the future.The analysis found that the breakdown pressure of ScCO_(2)was reduced 6.52%–52.31%compared with that of using water.ScCO_(2)tends to produce a complex fracture morphology with significantly higher permeability.When compared with water,the fracture aperture of ScCO_(2)was decreased by 4.10%–72.33%,the tortuosity of ScCO_(2)was increased by 5.41%–70.98%and the fractal dimension of ScCO_(2)was increased by 4.55%–8.41%.The breakdown pressure of sandstone is more sensitive to the nature of the fracturing fluid,but fracture aperture is less sensitive to fracturing fluid than for shale and coal.Compared with granite,the tortuosity of sedimentary rock is more sensitive to the fracturing fluid and the fracture fractal dimension is less sensitive to the fracturing fluid.Existing research shows that ScCO_(2)has the advantages of low breakdown pressure,good fracture creation and environmental protection.It is recommended that research be conducted in terms of sample terms,experimental conditions,effectiveness evaluation and theoretical derivation in order to promote the application of ScCO_(2)reformed reservoirs in the future. 展开更多
关键词 sedimentary rock supercritical carbon dioxide fracturing experiment breakdown pressure fracture parameters
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The geomechanics of Shenhua carbon dioxide capture and storage(CCS) demonstration project in Ordos Basin,China 被引量:8
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作者 Xiaochun Li Qi Li +2 位作者 Bing Bai Ning Wei Wei Yuan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第6期948-966,共19页
Carbon dioxide(CO2) capture and storage(CCS) is considered widely as one of promising options for CO2emissions reduction,especially for those countries with coal-dominant energy mix like China.Injecting and storing a ... Carbon dioxide(CO2) capture and storage(CCS) is considered widely as one of promising options for CO2emissions reduction,especially for those countries with coal-dominant energy mix like China.Injecting and storing a huge volume of CO2in deep formations are likely to cause a series of geomechanical issues,including ground surface uplift,damage of caprock integrity,and fault reactivation.The Shenhua CCS demonstration project in Ordos Basin,China,is the first and the largest full-chain saline aquifer storage project of CO2in Asia.The injection started in 2010 and ended in 2015.during which totally 0.3 million tonnes(Mt) CO2was injected.The project is unique in which CO2was injected into 18 sandstone formations simultaneously and the overlying coal seams will be mined after the injection stopped in 2015.Hence,intense geomechanical studies and monitoring works have been conducted in recent years,including possible damage resulting from the temperature difference between injected CO2and formations,injection induced stress and deformation change,potential failure mode and safety factor,interaction between coal mining and CO2geological storage,determination of injection pressure limit,and surface monitoring by the interferometric synthetic aperture radar(InSAR) technology.In this paper,we first described the background and its geological conditions of the Shenhua CCS demonstration project.Then,we gave an introduction to the coupled thermo-hydro-mechano-chemical(THMC) processes in CO2geological storage,and mapped the key geomechanical issues into the THMC processes accordingly.Next,we proposed a generalized geomechanical research flowchart for CO2geological storage projects.After that,we addressed and discussed some typical geomechanical issues,including design of injection pressure limit.CO2injection induced near-field damage,and interaction between CO2geological storage and coal mining,in the Shenhua CCS demonstration project.Finally,we concluded some insights to this CCS project. 展开更多
关键词 Mechanical stability carbon dioxide(CO_2) geological storage Injection pressure limit Caprock integrity Coal mining
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Characterization of carbon dioxide leakage process along faults in the laboratory 被引量:1
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作者 Lifeng Xu Qi Li +1 位作者 Yongsheng Tan Xiaochun Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第3期674-688,共15页
It is important to understand the process of multiphase carbon dioxide(CO_(2))leakage in faults for the risk assessment of carbon capture and storage(CCS).To quantitatively characterize the CO_(2)leakage process in th... It is important to understand the process of multiphase carbon dioxide(CO_(2))leakage in faults for the risk assessment of carbon capture and storage(CCS).To quantitatively characterize the CO_(2)leakage process in the fault,pressure sensors,fiber Bragg grating(FBG)temperature and strain sensors were simultaneously used to monitor CO_(2)leakage in the fault.Ten experiments were carried out,including five groups of gaseous CO_(2)leakage tests with initial pressures of 1-5 MPa and five groups of liquid CO_(2)leakage tests with initial pressures of 6-10 MPa.The results indicate that when liquid CO_(2)leaked with an initial pressure of 7-10 MPa,the pressure and temperature of CO_(2)dropped rapidly in the first few seconds and then remained unchanged.The behavior that CO_(2)continues to leak while maintaining temperature and pressure unchanged is defined as“temporary pseudo-sealing(TPS)”behavior,which continues for the first 1/3 of the leakage period.However,this TPS behavior did not occur in gaseous CO_(2)leakage.If only the pressure and temperature data were used to evaluate whether CO_(2)leakage occurred,we would misjudge the risk of leakage in CCS projects during the TPS period.The causes and conditions of TPS behavior were further studied experimentally.The results show that:(1)TPS behavior is caused by the phase transition energy generated when liquid CO_(2)leaks.(2)The condition for TPS behavior is a small leak aperture(0.2 mm).Only a small leakage rate can make the phase transition energy and pressure change from a dynamic equilibrium,and(3)The compression zone caused by the Bernoulli effect and fault“barrier”could reduce the CO_(2)leakage rate and further promote the occurrence of TPS behavior.This study provides technical and theoretical support for the quantitative characterization of the CO_(2)leakage process in faults of CCS projects. 展开更多
关键词 carbon dioxide(CO_(2))leakage Fault strain Temporary pseudo-sealing(TPS) pressure front Fiber bragg grating(FBG)sensor Risk management
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Analysis of the Law of Organic Solid Phase Precipitation and Deposition during Carbon Dioxide Displacement Process
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作者 Peng Yu 《Journal of Geoscience and Environment Protection》 2019年第1期118-122,共5页
Carbon Capture, Utilization and Storage (CCUS) has been regarded as an indispensable, strategic and pressing technology to reduce anthropogenic carbon dioxide emissions, and mitigate the severe consequences of climate... Carbon Capture, Utilization and Storage (CCUS) has been regarded as an indispensable, strategic and pressing technology to reduce anthropogenic carbon dioxide emissions, and mitigate the severe consequences of climate change. Its utilization and storage play important roles in this system and they can be applied for oceanic and underground geological sequestration especially for the oil gas reservoir that needs to improve recovery. For the carbon dioxide flooding process, the crude oil displacement generally shows a better performance with the increase of the pressure. However, carbon disposal is always complex. It could encounter organic solid phase precipitation and deposition in near miscibility environment. The law of multiphase and multicomponent diversification in the whole processes is still poorly understood. We thus used the method of slim tube to get dynamic data during the process. Indeed, the interval of near minimum miscibility pressure was determined. Analysis results of injectivity index and productivity index show that the reservoir blockage primarily appears as the displacement pressure is higher than the near minimum miscibility lower limit pressure and plays an important role in the production capacity. Extortionate or low pressure is not conducive to carbon dioxide displacement. 展开更多
关键词 ORGANIC Solid Phase Precipitaion and DEPOSITION carbon dioxide DISPLACEMENT BLOCKAGE Near Minimum MISCIBILITY pressure
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Blocking Behavior of Organic Solid Phase in the Carbon Dioxide Multiphase and Multicomponent Displacement Process
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作者 Peng Yu 《Journal of Power and Energy Engineering》 2019年第1期183-189,共7页
Better dealing with carbon issues can support the management of current greenhouse gas emissions while achieving energy economic diversification and energy security. Carbon dioxide displacement has become the most ack... Better dealing with carbon issues can support the management of current greenhouse gas emissions while achieving energy economic diversification and energy security. Carbon dioxide displacement has become the most acknowledged and practical method in enhanced oil recovery system. This is because of its oil sweep efficiency and ability to reduce the level of greenhouse gas emission. Nevertheless, it would lead to the organic solid phase deposition, which causes the changes of the wettability and the damages of wellbores and reservoirs. In this study, we used slim tube test and component test to research the dynamic characteristics of displacement process. In addition, the mechanism of porous media blockage was also investigated. Results show that when the displacement pressure closed to the minimum miscibility pressure, reservoir blockage in pore throat could happen. Component test characterizes that during near miscible displacement process, the components of oil sample varied obviously, the variation range of peak component carbon marks fluctuated strongly. Crude oil component differentiation could happen after carbon dioxide fully contacted with oil. Besides, the rapid extraction mechanism of aromatic hydrocarbons played a significant role in this process under such condition. The reason is that the solubility of saturated hydrocarbons to asphaltene and non-hydrocarbons is obviously weaker than aromatic hydrocarbons. Controlling the pressure is considered as an important link to prevent the occurrence of blocking in the carbon dioxide multiphase and multicomponent displacement process. 展开更多
关键词 BLOCKING BEHAVIOR ORGANIC Solid Phase carbon dioxide Displacement MULTIPHASE and MULTICOMPONENT Near Minimum MISCIBLE pressure
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Synthesis of poly (vinyl acetate) oligomersand their phase behavior in supercritical carbon dioxide
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作者 Jiao Zhen Song Junying +2 位作者 Fan Wenjing Wang Xiudong Wang Ziyi 《Journal of Southeast University(English Edition)》 EI CAS 2019年第2期264-268,共5页
Three poly(vinyl acetate)(PVAc)oligomers with controlled molecular weight and narrow molecular distribution are synthesized by reversible addition-fragmentation chain transfer(RAFT)polymerization.The effects of the re... Three poly(vinyl acetate)(PVAc)oligomers with controlled molecular weight and narrow molecular distribution are synthesized by reversible addition-fragmentation chain transfer(RAFT)polymerization.The effects of the reaction temperature and the added amount of initiator of the PVAc polymerization are discussed.In addition,the phase behavior of the prepared PVAc in pressured CO2 is determined via the cloud point method.The results indicate that the cloud point of PVAc increases with the increase in the molecular weight,the PVAc concentration,and the temperature.The cloud point pressures for the PVAc mass concentration of 0.12%with the molecular weight of 1 550,2 120,and 2 960 g/mol are 13.48,13.83 and 15.43 MPa,respectively,at the temperature of 35℃.It reveals that the solubility of PVAc in ScCO2 at relatively low pressure is remarkably limited. 展开更多
关键词 poly(vinyl acetate) POLYMERIZATION supercritical carbon dioxide cloud point pressure CO2-philic polymer
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Changes of end-tidal carbon dioxide during cardiopulmonary resuscitation from ventricular f ibrillation versus asphyxial cardiac arrest 被引量:7
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作者 Qing-ming Lin Xiang-shao Fang +3 位作者 Li-li Zhou Yue Fu Jun Zhu Zi-tong Huang 《World Journal of Emergency Medicine》 CAS 2014年第2期116-121,共6页
BACKGROUND: Partial pressure of end-tidal carbon dioxide(PETCO2) has been used to monitor the effectiveness of precordial compression(PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation... BACKGROUND: Partial pressure of end-tidal carbon dioxide(PETCO2) has been used to monitor the effectiveness of precordial compression(PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation(CPR). This study was to investigate changes of PETCO2 during CPR in rats with ventricular fi brillation(VF) versus asphyxial cardiac arrest.METHODS: Sixty-two male Sprague-Dawley(SD) rats were randomly divided into an asphyxial group(n=32) and a VF group(n=30). PETCO2 was measured during CPR from a 6-minute period of VF or asphyxial cardiac arrest.RESULTS: The initial values of PETCO2 immediately after PC in the VF group were signifi cantly lower than those in the asphyxial group(12.8±4.87 mmHg vs. 49.2±8.13 mmHg, P=0.000). In the VF group, the values of PETCO2 after 6 minutes of PC were significantly higher in rats with return of spontaneous circulation(ROSC), compared with those in rats without ROSC(16.5±3.07 mmHg vs. 13.2±2.62 mmHg, P=0.004). In the asphyxial group, the values of PETCO2 after 2 minutes of PC in rats with ROSC were signifi cantly higher than those in rats without ROSC(20.8±3.24 mmHg vs. 13.9±1.50 mmHg, P=0.000). Receiver operator characteristic(ROC) curves of PETCO2 showed signifi cant sensitivity and specifi city for predicting ROSC in VF versus asphyxial cardiac arrest.CONCLUSIONS: The initial values of PETCO2 immediately after CPR may be helpful in differentiating the causes of cardiac arrest. Changes of PETCO2 during CPR can predict outcomes of CPR. 展开更多
关键词 partial pressure of end-tidal carbon dioxide Cardiac arrest Cardiopulmonary resuscitation Return of spontaneous circulation RATS
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Temporal and spatial variability of the carbon cycle in the east of China's seas:a three-dimensional physical-biogeochemical modeling study 被引量:1
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作者 JI Xuanliang LIU Guimei +2 位作者 GAO Shan WANG Hui ZHANG Miaoyin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第3期60-71,共12页
In the east of China's seas, there is a wide range of the continental shelf. The nutrient cycle and the carbon cycle in the east of China's seas exhibit a strong variability on seasonal to decadal time scales. On th... In the east of China's seas, there is a wide range of the continental shelf. The nutrient cycle and the carbon cycle in the east of China's seas exhibit a strong variability on seasonal to decadal time scales. On the basis of a regional ocean modeling system(ROMS), a three dimensional physical-biogeochemical model including the carbon cycle with the resolution(1/12)°×(1/12)° is established to investigate the physical variations, ecosystem responses and carbon cycle consequences in the east of China's seas. The ROMS-Nutrient Phytoplankton Zooplankton Detritus(NPZD) model is driven by daily air-sea fluxes(wind stress, long wave radiation, short wave radiation, sensible heat and latent heat, freshwater fluxes) that derived from the National Centers for Environmental Prediction(NCEP) reanalysis2 from 1982 to 2005. The coupled model is capable of reproducing the observed seasonal variation characteristics over the same period in the East China Sea. The integrated air-sea CO_2 flux over the entire east of China's seas reveals a strong seasonal cycle, functioning as a source of CO_2 to the atmosphere from June to October, while serving as a sink of CO_2 to the atmosphere in the other months. The 24 a mean value of airsea CO_2 flux over the entire east of China's seas is about 1.06 mol/(m^2·a), which is equivalent to a regional total of3.22 Mt/a, indicating that in the east of China's seas there is a sink of CO_2 to the atmosphere. The partial pressure of carbon dioxide in sea water in the east of China's seas has an increasing rate of 1.15 μatm/a(1μtm/a=0.101 325Pa), but p H in sea water has an opposite tendency, which decreases with a rate of 0.001 3 a^(–1) from 1982 to 2005.Biological activity is a dominant factor that controls the pCO_2 air in the east of China's seas, and followed by a temperature. The inverse relationship between the interannual variability of air-sea CO_2 flux averaged from the domain area and Ni?o3 SST Index indicates that the carbon cycle in the east of China's seas has a high correlation with El Ni?o-Southern Oscillation(ENSO). 展开更多
关键词 the east of China's seas physical-biogeochemical model partial pressure of carbon dioxide in sea water air-sea CO2 flux
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Fuzzy Logic for Solving an Optimal Control Problem of Hypoxemic Hypoxia Tissue Blood Carbon Dioxide Exchange during Physical Activity 被引量:1
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作者 Jean Marie Ntaganda Mahamat Saleh Daoussa Haggar Benjamin Mampassi 《Open Journal of Applied Sciences》 2014年第11期501-514,共14页
This paper aims at using of an approach integrating the fuzzy logic strategy for hypoxemic hypoxia tissue blood carbon dioxide human optimal control problem. To test the efficiency of this strategy, the authors propos... This paper aims at using of an approach integrating the fuzzy logic strategy for hypoxemic hypoxia tissue blood carbon dioxide human optimal control problem. To test the efficiency of this strategy, the authors propose a numerical comparison with the direct method by taking the values of determinant parameters of cardiovascular-respiratory system for a 30 years old woman in jogging as her regular physical activity. The results are in good agreement with experimental data. 展开更多
关键词 Fuzzy LOGIC Optimal Control MEMBERSHIP Function MEMBERSHIP DEGREE Hypoxemic-Hypoxia pressure carbon dioxide Oxygen Numerical Simulation
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Extraction of copper ions by supercritical carbon dioxide
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作者 Cui, Z. Liu, J. +1 位作者 Gao, L. Wei, Y. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第4期444-447,共4页
Complexation combined with supercritical fluid extraction was used to extract Cu2+ in this study. The effects of pressure, temperature, volume of CO2 on the efficiency of extraction were systematically investigated. A... Complexation combined with supercritical fluid extraction was used to extract Cu2+ in this study. The effects of pressure, temperature, volume of CO2 on the efficiency of extraction were systematically investigated. At the optimum condition a 57.32% recovery was achieved. Addition of suitable amount of methanol (v/v = 5%) to the supercritical CO2 can increase in the extraction of Cu2+ (72.69%, RSD = 2.12%, n = 3). And the recovery can further increase in the presence of non-ionic surfactant Triton X-100 because of its function of solubilization. Surfactant was first used in the extraction of metal ions in the present study, and the results are satisfied (90.52%, RSD = 2.20%, n = 3). 展开更多
关键词 carbon dioxide CHELATION COPPER METHANOL Positive ions pressure effects SOLUBILITY Surface active agents thermal effects
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Determination of Critical Parameters of Carbon Dioxide+Butyraldehyde System with Different Compositions
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作者 ZHANG Jing-chang GAO Xi-xin CAO Wei-liang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第6期687-691,共5页
Supercritical carbon dioxide(SC-CO2 ) is considered in green chemistry as a substitute for conventional solvents in chemical reactions due to its environmentally benign character. Recently we have reported the homog... Supercritical carbon dioxide(SC-CO2 ) is considered in green chemistry as a substitute for conventional solvents in chemical reactions due to its environmentally benign character. Recently we have reported the homogeneous hydroformylation of propylene in supercritical carbon dioxide( SC-CO2 ) , which is an example of this kind of application of carbon dioxide. The determination for the critical parameters of carbon dioxide + butyraldehyde mixtures is necessary for this reaction design which is the focus of the present paper. The critical parameters of the binary systems were determined via the static visual method at a constant volume with the molar fraction of butyraldehyde ranging from 1.0% to 2. 2% and the pressure ranging from 5 to 10 MPa. The experimental results show that the critical pressure and temperature increased with increasing the molar fraction of butyraldehyde. The bubble(dew) temperatures and the bubble (dew) pressures for the binary systems were also determined experimentally. The p-T Figures at different compositions of the binary systems were described. In addition, the critical compressibility factors Zc of the binary systems at different concentrations of n-butyraldehyde were calculated. It was found that the critical compressibility factor values of the binary systems decreased with increasing the molar fraction of n-butyraldehyde in the experimental range. 展开更多
关键词 carbon dioxide butyraldehyde binary system Critical temperature Critical pressure p-T Figure Critical compressibility factor
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Effect of Different Drugs on End-tidal Carbon Dioxide during Rodent CPR
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作者 潘铁成 周淑华 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1997年第4期244-246,共3页
The purpose of this study was to investigate the effect of nonadrenergic agents on cardiopulmonary resuscitation (CPR) and end-tidal CO2(ETCO2)during CPR in a rodent model. Our results suggested that: 1) coronary perf... The purpose of this study was to investigate the effect of nonadrenergic agents on cardiopulmonary resuscitation (CPR) and end-tidal CO2(ETCO2)during CPR in a rodent model. Our results suggested that: 1) coronary perfusion pressure (CPP) after drugs infusion was increased significantly by methoxamine, arginine vasopresin (AVP) and angiotension- Ⅱ(ANG- Ⅱ), but not by endothelin-1 (ET-1): 2) ETCO2 prior to defibrillation was decreased significantly by a pure a1 adrenergic agents,methoxamine and were increased significantly by non-adrenergic agents, ANG-Ⅱ and ET-1 during rodent CPR;3) a significant positive correlation between ETCO2 and CPP was observed in AVP group, suggesting that AVP have little effect on pulmonary circulation; and 4) methoxamine, AVP and ANG-Ⅱ have similar effect on resuscitability during rodent CPR. 展开更多
关键词 cardiopulmonary resuscitation coronary perfusion pressure end-tidal carbon dioxide METHOXAMINE arginine vasopressin angiotensin-Ⅱ endothelin-1
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Arterial and End-Tidal Carbon Dioxide in Supine Obese Patients during General Anesthesia
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作者 Kenichi Satoh Mami Chikuda +4 位作者 Ayako Ohashi Miho Kumagai Masahito Sato Akiyoshi Kuji Shigeharu Joh 《Open Journal of Anesthesiology》 2015年第5期79-84,共6页
Background: We investigated the differences between partial pressure of arterial carbon dioxide and end-tidal carbon dioxide (P(a-ET)CO2) with respect to the Broca-Katsura index (BKI), which is an obesity index, in ob... Background: We investigated the differences between partial pressure of arterial carbon dioxide and end-tidal carbon dioxide (P(a-ET)CO2) with respect to the Broca-Katsura index (BKI), which is an obesity index, in obese patients during general anesthesia. Materials and Methods: From January 2003 to December 2013, we studied 601 patients aged 16 years old or over undergoing general anesthesia. Patients had American Society of Anesthesiology physical status I and II and we reviewed their anesthetic charts. The P(a-ET)CO2 with respect to the BKI divided patients into two groups: 16 to 2 values between the two groups. Results: In patients aged 16 to 2 was 2.2 ± 3.1 mmHg at BKI 2 was 3.2 ± 4.1 mmHg at BKI 2 tends to increase in obese patients during general anesthesia with increasing BKI in patients aged 16 to < 65 years old. 展开更多
关键词 Arterial-Alveolar carbon dioxide Tension Difference Broca-Katsura Index End-Tidal carbon dioxide partial pressure of ARTERIAL carbon dioxide SUPINE Position
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Analysis of CO<sub>2</sub>Pressure Swing Adsorption Simulation by Considering the Transport Phenomena in the Adsorber
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作者 Takehiro Esaki Hideaki Kuronuma Noriyuki Kobayashi 《Journal of Materials Science and Chemical Engineering》 2021年第3期39-54,共16页
This study focused on CO<sub>2</sub> separation technology with adsorption. This paper describes the analysis carried out by a CO<sub>2</sub> pressure swing adsorption simulation to scale up th... This study focused on CO<sub>2</sub> separation technology with adsorption. This paper describes the analysis carried out by a CO<sub>2</sub> pressure swing adsorption simulation to scale up the absorber. An unsteady one-dimensional balance model was constructed by considering the material, energy, and momentum. In the CO<sub>2</sub> breakthrough test, the beginning time and CO<sub>2</sub> concentration at outlet of CO<sub>2</sub> breakthrough in the calculation were almost equivalent to that of experiment results. The correlation consistency of the calculation results with the analysis model and the experimental results obtained by a bench scale experiment was evaluated. The transport phenomena in the adsorber were investigated at the adsorption, rinse, and desorption steps according to the calculation results. The starting time of CO<sub>2</sub> breakthrough obtained by the analysis is equal to that obtained by the adsorption breakthrough experiment. This confirms that the CO<sub>2</sub> adsorption, and the temperature and velocity distribution in the adsorber, change as a function of the adsorption, rinse, and desorption steps, respectively. Additionally, the CO<sub>2</sub> concentration of the captured gas and the amount of CO<sub>2</sub> quantity were 93.4% per day and 2.9 ton/day, respectively. These values are equal to those obtained by the bench scale experiment. 展开更多
关键词 carbon dioxide Separation pressure Swing Adsorption Numerical Analysis
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Carbon Dioxide/Methane Separation by Adsorption on Sepiolite 被引量:10
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作者 José A.Delgado María A.Uguina +2 位作者 José L.Sotelo Beatriz Ruíz Marcio Rosário 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第3期235-243,共9页
In this work, the use of sepiolite for the removal of carbon dioxide from a carbon dioxide/methane mixture by a pressure swing adsorption (PSA) process has been researched. Adsorption equilibrium and kinetics have b... In this work, the use of sepiolite for the removal of carbon dioxide from a carbon dioxide/methane mixture by a pressure swing adsorption (PSA) process has been researched. Adsorption equilibrium and kinetics have been measured in a fixed-bed, and the adsorption equilibrium parameters of carbon dioxide and methane on sepiolite have been obtained. A model based on the LDF approximation has been employed to simulate the fixed-bed kinetics, using the Langmuir equation to describe the adsorption equilibrium isotherm. The functioning of a PSA cycle for separating carbon dioxide/methane mixtures using sepiolite as adsorbent has also been studied. The experimental results were compared with the ones predicted by the model adapted to a PSA system. Methane with purity higher than 97% can be obtained from feeds containing carbon dioxide with concentrations ranging from 34% to 56% with the proposed PSA cycle. These results suggest that sepiolite is an adsorbent with good properties for its employment in a PSA cycle for carbon dioxide removal from landfill gases. 展开更多
关键词 carbon dioxide METHANE SEPIOLITE ADSORPTION FIXED-BED pressure swing adsorption
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pCO_2 and carbon fluxes across sea-air interface in the Changjiang Estuary and Hangzhou Bay 被引量:6
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作者 高学鲁 宋金明 +2 位作者 李学刚 李宁 袁华茂 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第3期289-295,共7页
Partial pressure of CO2(pCO2) was investigated in the Changjiang(Yangtze River) Estuary,Hangzhou Bay and their adjacent areas during a cruise in August 2004,China.The data show that pCO2 in surface waters of the studi... Partial pressure of CO2(pCO2) was investigated in the Changjiang(Yangtze River) Estuary,Hangzhou Bay and their adjacent areas during a cruise in August 2004,China.The data show that pCO2 in surface waters of the studied area was higher than that in the atmosphere with only exception of a patch east of Zhoushan Archipelago.The pCO2 varied from 168 to 2 264 μatm,which fell in the low range compared with those of other estuaries in the world.The calculated sea-air CO2 fluxes decreased offshore and varied from -10.0 to 88.1 mmol m-2 d-1 in average of 24.4 ± 16.5 mmol m-2 d-1.Although the area studied was estimated only 2 × 104 km2,it emitted(5.9 ± 4.0) × 103 tons of carbon to the atmosphere every day.The estuaries and their plumes must be further studied for better understanding the role of coastal seas playing in the global oceanic carbon cycle. 展开更多
关键词 partial pressure of carbon dioxide spatial distribution sea-air exchange Changjiang Estuary Hangzhou Bay
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Effect of early goal directed therapy on tissue perfusion in patients with septic shock 被引量:19
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作者 Yuan-hua Lu Ling Liu +3 位作者 Xiao-hua Qiu Qin Yu Yi Yang Hai-bo Qiu 《World Journal of Emergency Medicine》 CAS 2013年第2期117-122,共6页
BACKGROUND:This study aimed to observe the effect of early goal directed therapy(EGDT)on tissue perfusion,microcirculation and tissue oxygenation in patients with septic shock.METHODS:Patients with early septic shock(... BACKGROUND:This study aimed to observe the effect of early goal directed therapy(EGDT)on tissue perfusion,microcirculation and tissue oxygenation in patients with septic shock.METHODS:Patients with early septic shock(<24 hours) who had been admitted to the ICU of Zhongda Hospital Affiliated to Southeast University from September 2009 through May 2011 were enrolled(research time:12 months),and they didn't meet the criteria of EGDT.Patients who had one of the following were excluded:stroke,brain injury,other types of shock,severe heart failure,acute myocardial infarction,age below 18 years,pregnancy,end-stage disease,cardiac arrest,extensive burns,oral bleeding,difficulty in opening the mouth,and the onset of septic shock beyond 24 hours.Patients treated with the standard protocol of EGDT were included.Transcutaneous pressure of oxygen and carbon dioxide(PtcO_2,PtcCO_2) were monitored and hemodynamic measurements were obtained.Side-stream dark field(SDF) imaging device was applied to obtain sublingual microcirculation.Hemodynamics,tissue oxygen,and sublingual microcirculation were compared before and after EGDT.If the variable meets the normal distribution,Student's t test was applied.Otherwise,Wilcoxon's rank-sum test was used.Correlation between variables was analyzed with Pearson's product-moment correlation coefficient method.RESULTS:Twenty patients were involved,but one patient wasn't analyzed because he didn't meet the EGDT criteria.PtcO_2 and PtcCO_2 were monitored in 19 patients,of whom sublingual microcirculation was obtained.After EGDT,PtcO_2 increased from 62.7+24.0 mmHg to 78.0±30.9mmHg(P<0.05) and tissue oxygenation index(PtcO_2/FiO_2) was 110.7+60.4 mmHg before EGDT and 141.6±78.2 mmHg after EGDT(P<0.05).The difference between PtcCO_2 and PCO_2 decreased significantly after EGDT(P<0.05).The density of perfused small vessels(PPV) and microcirculatory flow index of small vessels(MFI) tended to increase,but there were no significant differences between them(P>0.05).PtcO_2,PtcO_2/FiO_2,and PtcCO_2 were not linearly related to central venous saturation,lactate,oxygen delivery,and oxygen consumption(P>0.05).CONCLUSION:Peripheral perfusion was improved after EGDT in patients with septic shock,and it was not exactly reflected by the index of systemic perfusion. 展开更多
关键词 Transcutaneous pressure of oxygen Transcutaneous pressure of carbon dioxide MICROCIRCULATION Septic shock EGDT Tissue perfusion Tissue oxygenation Sidestream dark field imaging
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